Documents published in 2017 : Scipedia

Managing Motorways and Urban Arterials in Australia: Country Report for Australia
R. Troutbeck, D. Walsh, M. Blogg

Collection of Transportation Research Procedia (2017).

Abstract
Australian States have been investing heavily in managed motorway. It was acknowledged some time ago that the motorways that had slow moving congested traffic caused a considerable loss of value to the community. The concept of Productivity was applied to Motorways and since become a key performance indicator used to rate different motorway systems. The approach to motorway management has been based on established practices overseas although different algorithms are being developed in Australia and subsequently evaluated. This paper describes the processes used by Australian States to manage motorways and it describes the current research into new techniques. The management of motorways cannot be undertaken without consideration of the urban arterial network. It is therefore important to see the network as a whole noting that drivers tend to change their routes so that both the motorways and the arterial work in unison to provide the level of service to the user. It is therefore important that the performance of the arterial road system be maximised. The paper outlines some of the research that is directed at maximising the arterial road, using detectors on the departure side of signalized intersections to evaluating the potential for significant improvement in signal re-timing. Finally the paper will outline the use of the Highway Capacity Manual in Australian traffic engineering practices. It should be understood that Australia has used SIDRA for intersection analysis for some time and although many of the concepts of the HCM are used in SIDRA, it contains many elements and calibration factors that are peculiar to Australia.
Abstract
Australian States have been investing heavily in managed motorway. It was acknowledged some time ago that the motorways that had slow moving congested traffic caused a considerable [...]
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Preparing a Roadmap for Connected Vehicle/Cooperative Systems Deployment Scenarios: Case Study of the State of Oregon, USA
R. Bertini, H. Wang, T. Knudson, K. Carstens

Collection of Transportation Research Procedia (2017).

Abstract
Safety remains a problem on U.S. roadways, with more than 32, 000 fatalities, 2.2 million injuries and 6 million crashes each year. Travelers, shippers and the economy are exposed to increasing amounts of congestion, unreliability, delay, emissions and excess energy consumption, which impede the efficient movement of people and goods. The U.S. Department of Transportation (DOT) had embarked upon a major research program toward implementing connected vehicle safety technologies, applications and systems using dedicated, short-range wireless communications (DSRC). Previous research by the National Highway Traffic Safety Administration (NHTSA) demonstrated that 80% of unimpaired driver crash types could be addressed by the connected vehicle technology. Through the year-long Safety Pilot that took place in Michigan from 2012 to 2013, U.S. DOT tested the effectiveness of wireless connected vehicle technology in real-world, multimodal driving conditions, collecting data about how ordinary drivers adapt to the use of connected vehicle technology, and identifying the potential safety benefits of connected vehicle technology. This work was performed in recognition of a February 3, 2014 NHTSA agency decision for light vehicles and a similar decision expected soon for commercial vehicles that will likely launch regulatory processes to require or incentivize all new vehicles to be equipped with DSRC devices. Communication among and between vehicles and the infrastructure (including traffic signals, work zone equipment, or pavement sensors, and other infrastructure elements) would also have data and mobility benefits (including data-driven applications such as traveler information for freight and passengers, transit operations, network flow optimization, traffic signal systems and incident response, emergency staging, and evacuation as well as sustainability-related applications). This paper describes an ongoing effort to explore opportunities for the state of Oregon, USA, to participate in future funded pilot deployments of mobility and environmental related applications in the coming years—possibly including a set of regional pilots as well as smaller, more self-contained projects focused on priority applications. As connected vehicle research moves into deployment, state, local and transit agencies, Metropolitan Planning Organizations and the private sector will start experiencing the effects of vehicles, after-market devices, mobile devices, and infrastructure with DSRC and other wireless connectivity at their cores. Along with other states and regions, the Oregon Department of Transportation (ODOT) can benefit from preliminary scoping, evaluation, and assessment of the impact of connected vehicles and infrastructure and a wide range of potential cooperative system applications. With this in mind, ODOT can determine whether or not to pursue the next phases of federal connected vehicle application funding. It can also make an informed choice about taking a potential national leadership role in the connected vehicle arena, and assess opportunities to join projects with other partners. This paper provides a summary of an internal survey conducted within ODOT along with insights gained from the analysis of the survey results. Next steps in the process are also described.
Abstract
Safety remains a problem on U.S. roadways, with more than 32, 000 fatalities, 2.2 million injuries and 6 million crashes each year. Travelers, shippers and the economy are [...]
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Development of a Mobility-Based Service Measure for Freeway Facilities
R. Margiotta, D. McLeod, T. Scorsone

Collection of Transportation Research Procedia (2017).

Abstract
The Highway Capacity Manual (HCM) currently uses a bipolar approach to defining level of service (LOS) for freeway facilities: either (1) weighted density or (2) assigning LOS F if one or more segments experience LOS F. The major shortcoming of this approach is that density is a poor indicator of travelers’ experiences under congested conditions, speeds or travel times are more relevant to travelers and are consistent with how agencies measure and report congestion using field data. Likewise, saying a facility operates at LOS F if one only segment experiences LOS F is misleading. Further, five of the six LOS ranges exist where speeds are relatively high (above approximately 50 mph) and only one LOS range is used to define the congested regime, which is of the highest interest in large urbanized areas. Especially with regard to operations improvements, many congestion management techniques will improve congestion (e.g., delay) but the facility will still be classified as LOS F under the current definition. This paper deals with this issue by defining a travel time-based service measure for freeway facilities. Two HCM applications are explored: (1) traditional(static) freeway analysis and (2) the new travel time reliability (TTR) analysis procedure. Several performance measures are explored for the service measures by analyzing field data from seven U.S. urban areas. Although the research is not complete as of this writing, the mean travel time index is probably the best measure for the static procedure and either the 80th or 95th percentile travel time index should be used with the reliability procedure. Analysis of field data revealed strong correlation between the mean and upper percentiles of the travel time distribution, so these measures are internally consistent. A shift away from the current density-based LOS structure is recommended. The new structure uses ranges of the selected travel time measures that indicate different levels of the user experience. This approach is similar to what is done in the HCM for urban streets. Reconciling LOS concepts between freeways and urban streets will make the HCM more usable for the emerging field of performance management. It is recommended that travel time reliability be the service measure for freeway facilities which are part of an extensive freeway network in large urbanized areas, those over 500, 000 population. An extensive freeway network is defined as having at least three freeway facilities. Analysts should use their judgment in cases that do not meet these Density would continue to be used on all other freeway facilities as well as for other aspects of freeways covered by the HCM (e.g., freeway segments). Recognizing that agencies may want to define their own service standards, a procedure for setting locally-defined standards is developed, based on the steps used in this research. It is expected that the freeway facility service measures will be an aid in setting transportation system and freight performance targets, a a demonstration of how they would be used for target setting is presented.
Abstract
The Highway Capacity Manual (HCM) currently uses a bipolar approach to defining level of service (LOS) for freeway facilities: either (1) weighted density or (2) assigning [...]
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Performance Benefits of Connected Vehicles for Implementing Speed Harmonization
R. Dowling, B. Nevers, A. Jia, A. Skabardonis, C. Krause, M. Vasudevan

Collection of Transportation Research Procedia (2017).

Abstract
This paper reports on the combined microsimulation and small scale demonstration evaluation of the freeway performance effects of a specific connected vehicle implementation of speed harmonization (The Prototype). The microsimulation testing was performed on a 10 mile stretch of freeway in San Mateo County, California. The small scale field demonstration was performed with 10 equipped vehicles on 17 miles of the I-5 freeway in Seattle, Washington. The microsimulation analysis evaluated the effects of the Prototype speed harmonization algorithm on shockwaves, queues, throughput, speed variation, travel time, and reliability, for different response rates for vehicles on the facility. The “response rate” is defined as the combination of the percent of the vehicle fleet with connected vehicle capabilities, the percent of connected vehicles that successfully receive the speed recommendation in a timely manner, and the percent of drivers who having received the recommendation also choose to comply with the recommended speed. Results from the simulation analysis found that the Prototype is likely to significantly reduce the magnitude of the speed differences (shockwaves) between vehicles, even at the 10-percent response rate. This is considered to benefit safety by reducing the probability of collisions where free-flowing traffic meets the back of a queue. The trade-off for the improved safety is that the Prototype increases the geographic impact of existing bottlenecks on freeway speeds by expanding the upstream distance that is affected by congestion. The small scale field demonstration evaluated the performance of a cell phone based application for communicating vehicle status and receiving recommended speeds and advanced queue warnings using a combination of the cellular network and roadside dedicated short range communication devices via a DSRC antenna installed in the vehicle. The small scale demonstration also evaluated the ability to detect queues via a combination of installed loop detectors in the road and basic safety messages transmitted by the connected vehicles. The small scale field demonstration showed the feasibility of connected vehicle data capture and dissemination functionality using both cellular communications and Dedicated Short Range (DSRC) communications. It demonstrated that the Prototype has the communication speeds, communication reliability, and computed processing speed to support speed harmonization application functionality in an operational traffic environment. This paper is based upon work supported by the Federal Highway Administration under contract number DTFH61-12-D-00044. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the Federal Highway Administration.
Abstract
This paper reports on the combined microsimulation and small scale demonstration evaluation of the freeway performance effects of a specific connected vehicle implementation [...]
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The Influence of General Purpose Lane Traffic on Managed Lane Speeds: An Operational Study in Houston, Texas
R. Avelar, K. Fitzpatrick, K. Dixon, T. Lindheimer

Collection of Transportation Research Procedia (2017).

Abstract
Freeway networks are a critical component of the transportation systems at large metropolitan areas. The use of managed lanes (MLs) is a very important tool in accommodating directional demand, often heavily asymmetrical at peak hours. Current literature establishes that operational performance of MLs may impact, and be impacted by, operations of adjacent general purpose lanes (GPs), despite some degree of physical separation. Such operational co-dependence may especially exist between the GP lane adjacent to the separation buffer and the ML lane. This paper examines how the operations of these lanes relate to each other. Operational data were collected from 2 freeway sites in Houston TX (U.S.A.) for analysis. Both sites feature a buffer separating a single ML from the GP lanes at each site. One of those sites features vertical pylons in its buffer while the other site does not. This dataset spans several months of year 2014, from January to December. Results highlight the influence of the left-most GP lane on the ML operational speed, as well as the apparent degree of mitigation to that influence that the presence of pylons provides.
Abstract
Freeway networks are a critical component of the transportation systems at large metropolitan areas. The use of managed lanes (MLs) is a very important tool in accommodating [...]
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Life Cycle Emissions and Cost Study of Light Duty Vehicles
P. Prevedouros, L. Mitropoulos

Collection of Transportation Research Procedia (2017).

Abstract
The growth of vehicle sales and use world-wide requires the consumption of significant quantities of energy and materials. Advanced propulsion systems and electric drive vehicles have substantially different characteristics and impacts. For a comprehensive comparison of advanced and traditional light duty vehicles, a model is developed that integrates external costs, including emissions and time losses, with societal and consumer life cycle costs. Life cycle emissions and time losses are converted into costs for seven urban light duty vehicles. The results, which are based on vehicle technology characteristics and transportation impacts on environment, facilitate vehicle comparisons and support policy making in transportation. More sustainable urban transportation can be achieved in the short term by promoting policies that increase vehicle occupancy. In the intermediate term, more sustainable urban transportation can be achieved by increasing the share of hybrid vehicles in traffic. In the long term, more sustainable urban transportation can be achieved with the widespread use of electric vehicles. A sensitivity analysis of life cost results revealed that vehicle costs change significantly for different geographical areas depending on vehicle taxation, and the pricing of gasoline, electric power and pollution. Current practices in carbon and air quality pricing favor oil and coal based technologies. However, increasing the cost of electricity from coal and other fossil fuels would increase the variable cost for electric vehicles, and would favor the variable cost of hybrid vehicles.
Abstract
The growth of vehicle sales and use world-wide requires the consumption of significant quantities of energy and materials. Advanced propulsion systems and electric drive vehicles [...]
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Expressway Traffic Demand Forecasts in the Volatile Economic Environment of Greece
P. Prevedouros, B. Halkias

Collection of Transportation Research Procedia (2017).

Abstract
The forecasting of expressway traffic demand for existing facilities is not particularly challenging for regions and countries with stable or moderately growing economies. In most cases the objective is to carefully establish a reliable estimate for the average annual growth for the next N years using demographic and macroeconomic inputs. Recent applications for freeways and rural highways in Hawaii indicate that the traditional methods using time series or tracking important trends, such as tourism in Hawaii, work well for horizons between 5 and 20 years. Models relying on growth do not adapt well to substantial decreases in traffic demand. A dramatic case is Greece, where a multitude of changes such as increased fuel taxes, reduced GDP, increased unemployment, increased car registration (or car ownership) taxes, and a collapsed new car market caused substantial reductions of traffic on all toll roads in the country, including the Attica Tollway in the capital city of Athens. Given several series of high quality monthly data from January 2005 to December 2012, a number of estimates and forecasts for Attica Tollway toll transactions were estimated. Toll transactions are a measure similar to average daily traffic. ADT represents a traffic load at a specific location whereas toll transactions are the total daily vehicle entries to the facility. Then the 2013 to mid-2015 actual data were used to evaluate the models. Autoregressive models were employed to arrive at toll transaction forecasts between 2013 and 2024. The models used International Monetary Fund (IMF) and Economist Intelligence Unit (EIU) forecasts of the GDP for Greece, as well as scenarios for future fuel prices. The impacts of the much increased fuel prices and of the economic and business downturns to traffic are obvious and the models capture them successfully. However, errors in the GDP forecasts cause errors in the predicted traffic. The stock market index appears to be a useful leading indicator with a two year lag.
Abstract
The forecasting of expressway traffic demand for existing facilities is not particularly challenging for regions and countries with stable or moderately growing economies. [...]
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Impact of Bottleneck Merge Control Strategies on Freeway Level of Service
O. Ramadan, V. Sisiopiku

Collection of Transportation Research Procedia (2017).

Abstract
Freeway work zones typically mandate lane closures that often induce bottlenecks. Merge maneuvers and the accompanying increase in the rate of lane changes at these bottlenecks can become problematic resulting in undesirable mobility and safety impacts. Traditionally, merge control strategies are deployed to mitigate such impacts. Literature sources indicate that available merge control strategies fall into one of four categories, namely: (i) early merge control, (ii) late merge control, (iii) temporary ramp metering, and (iv) mainline merge metering. However, little is known about the proper criteria for selecting and implementing one of the available merge control strategies. In addition, the impact of the various control strategies on freeway Level of Service (LOS) is currently under-researched. The purpose of this study is to evaluate the operational impacts of the above-mentioned freeway merge control strategies. The goal is to provide work-zone-aware LOS indicators that would help transportation agencies in selecting the most appropriate merge control strategy to minimally impact the freeway operations. In order to meet the research goals and objectives, this study used the CORSIM micro-simulation platform to evaluate impacts of various merge control strategies at a freeway study corridor in Birmingham, AL. The 2010 Highway Capacity Manual methods for calculating LOS were considered and modifications were proposed to align the calculated LOS with the assessed impacts of each merge control strategy. This study is significant for its contribution to providing transportation researchers and professionals with tools and methods to evaluate freeway LOS under work zone conditions and assisting them in mitigating the adverse impacts of work zones on traffic operations.
Abstract
Freeway work zones typically mandate lane closures that often induce bottlenecks. Merge maneuvers and the accompanying increase in the rate of lane changes at these bottlenecks [...]
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Capacity and Delay Estimation at Signalized Intersections Under Unsaturated Flow Condition Based on Cycle Overflow Probability
N. Wu, S. Giuliani

Collection of Transportation Research Procedia (2017).

Abstract
Capacity at signalized intersections is a basic parameter in urban transport networks. The capacity of a signalized intersection is a function of existing geometric, control, weather, and other conditions. Estimation of capacity at signalized intersections is one of the most important topics in traffic Engineering. If the capacity can directly be measured, the delay at signalized intersections and thus the traffic performance and quality of service can be calculated according to the functional relationship between delay and capacity. Unfortunately, under real world traffic conditions, the capacity cannot easily be measured directly for an existing intersection, especially under unsaturated flow conditions where the flow volume is lower than the capacity. This paper presents a model for estimating the capacity of an existing signalized intersection under unsaturated flow condition based on the cycle overflow probability which can be directly measured by loop detectors at stop lines. The cycle overflow probability is just the proportion of cycles with occupied detector at end of green time phases. Also the flow volume can directly be measured by loop detectors at stop lines. According to the queuing theory, the cycle overflow probability is a function of the degree of saturation, i.e. a function of flow volume and capacity. Thus, by measuring the cycle overflow probability and the flow volume, the capacity can be estimated according to the functional relationship. The proposed model is calibrated to data obtained from loop detectors at different signalized intersections under unsaturated conditions. For validation the model, the real capacities at the same intersections are measured for saturated cycles where the capacity can be considers as the measured volume. The proposed model delivers a useful tool for estimating capacity at signalized intersections under unsaturated conditions. Using the proposed model, the capacity and thus the traffic quality of service at existing signalized intersections can directly be estimated using data from loop detectors at stop lines. The model is theoretically reasonable and easily to use for practitioners. The results of the calibration and validation are very promising.
Abstract
Capacity at signalized intersections is a basic parameter in urban transport networks. The capacity of a signalized intersection is a function of existing geometric, control, [...]
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The New Procedures for Diverge, Merge, and Small Weaving Segments in the New Version of German Highway Capacity Manual (HBS 2015)
N. Wu, K. Lemke

Collection of Transportation Research Procedia (2017).

Abstract
The first version of German Highway Capacity Manual was published in 2001. Now, a new version is published in 2015 (HBS 2015). For the new German Highway Capacity Manual, most major chapters are revised and some of them are totally rewritten. The chapter for merge, diverge, and small weaving segments is rewritten in accordance with forthcoming developments in the past 10 years. In this paper, an overview of the chapter in the new German Highway Capacity Manual is presented. Procedures dealing with performance analyses and level of service (LOS) of those segments are introduced both for freeways and rural highways. Differences between the former version and the new version of the chapter in the German Highway Capacity Manual are indicated and discussed. In most of the existing highway capacity manuals, LOS of merge, diverge, and small weaving segments is traditionally defined by speed, volume, or density in critical areas. In that traditional concept several capacity values of different critical areas (merge, diverge, and weaving) as well as upstream and downstream basic segments within the influence areas are evaluated separately. In the new HBS 2015, a new model which considers the total merge, diverge, and weaving segment as an entire object is incorporated. A combined volume-to-capacity ratio (freeways) or a combined density (rural highways) is used for defining the LOS of the total segment. The parameters of the new procedure are functions of the number of lanes of the major road, the number of lanes in the on-ramp or off-ramp, and the predefined geometric design of those segments. The coefficients are calibrated with field data or defined by experts’ experiences within a matrix of coefficients. With those procedures, the traffic quality (LOS) can be obtained directly as a function of the volumes or densities on the major road and on the on-ramp or off-ramp respectively. The new procedure has the following advantages: a) a uniform function for all types of merge, diverge, and small weaving segments, b) traffic quality assessment for all critical areas under investigation in one step, and c) the procedure can easily be calibrated. For applications in practice, a set of graphs is provided.
Abstract
The first version of German Highway Capacity Manual was published in 2001. Now, a new version is published in 2015 (HBS 2015). For the new German Highway Capacity Manual, [...]
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Saturation Flow Rate Analysis at Signalized Intersections for Mixed Traffic Conditions in Motorcycle Dependent Cities
H. Nguyen

Collection of Transportation Research Procedia (2017).

Abstract
This article describes the results of a comprehensive saturation flow rate analysis at signalized intersections in motorcycle dependent cities. Most of current capacity analysis methods for signalized intersections consider vehicles moving on lanes, and they assume lane discipline and high driver discipline regarding traffic regulations. Moreover, for modeling mixed traffic conditions, the not lane-based heterogeneous real traffic flow is transferred into lane-based homogeneous flow by using Passenger Car Units. So far, available methods of capacity analysis do not consider the specific conditions of driver behaviour and traffic flow which are dominant e.g. in Vietnam or other countries where motorcycles have the major share in traffic. Consequently, there is a need to develop a proper method to allow such saturation flow rate analysis. The methodology of this research was developed with consideration of the specific traffic situation in Hochiminh City, Vietnam, a motorcycle dependent city. First, the article describes the unique aspects of traffic flow and saturation flow rate analysis under such mixed traffic conditions compared with car-dominated traffic, using data collected by observations of saturated flow conditions at 12 signalized intersections. Then, saturation flow rate models using a regression method are presented and described. The term of Motorcycle Unit (MCU) is introduced, and a set of factors which mainly affect the saturation flow in such mixed conditions is developed. These factors reflect major differences between the traffic flows under saturated conditions at signalized intersections in motorcycle dependent cities and car-dominated cites. For example, this includes the influence of the approach width, the impact of four-wheel vehicles (including car, bus, and truck) on motorcycles, the very specific interactions of left-turning and opposite straight-moving traffic streams, the relationship between right-turning 4-wheel vehicles and motorcycles moving straight in the same direction, and the phenomenon of capacity drop within the green time. Finally, a procedure to calculate the saturation flow rate for specific traffic situations is provided, and the application of the proposed model is depicted. The conducted research indicates that the proposed saturation flow rate analysis model is an appropriate approach to calculate the saturation flow rate for traffic streams at signalized intersections under such mixed traffic conditions. The set of motorcycle equivalent units used for analysis is also proved to be suitable for this model. Equations and graphs to determine the appropriate values for the identified influencing factors are presented. According to each specific traffic situation, calculation procedures are provided to determine the value of the saturation flow rate.
Abstract
This article describes the results of a comprehensive saturation flow rate analysis at signalized intersections in motorcycle dependent cities. Most of current capacity analysis [...]
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Human Ellipse of Indian Pedestrians
N. Singh, P. Parida, M. Advani, R. Gujar

Collection of Transportation Research Procedia (2017).

Abstract
The most important parameter for designing a pedestrian facility is the area required by a pedestrian to stand comfortably or make a comfortable movement. This area is referred as Body Ellipse (Human Ellipse) and depends on Shoulder Width and Body Depth of a human being (and also on the kind of activity i.e. Standing or Walking). In current practices, design of pedestrian facilities’ are according to the body ellipse of pedestrians experimented in The United States Of America (US-HCM 2010). Regional variances are marked in these physical characteristics that are dependent on human body dimensions to a greater extent, ultimately playing an important role in pedestrian’s convenience (capacity and Level of service of a facility) and design environment. This paper is an attempt to study the measurements of Body Ellipses i.e. body depth and shoulder width by carrying out videography surveys on the pedestrians in India (specifically Delhi). The analysis also includes, classifying the body dimensions according to gender and walking with/without baggage (handbag/backpack), along with the measurement of the Step length of pedestrians’ while walking which shall give out the area required for walking. These body dimensions have been compared with the standard body dimension available worldwide. The study location was a walkway in a commercial area in Delhi (India) with a sample size of 747 consisting of 132 females and 615 males. The extracted body dimension varies from 26.07 to 52.14 centimeter for body depth and 42.35 to 67.76 centimeters for shoulder width.
Abstract
The most important parameter for designing a pedestrian facility is the area required by a pedestrian to stand comfortably or make a comfortable movement. This area is referred [...]
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Shockwave Suppression by Vehicle-to-Vehicle Communication
N. Motamedidehkordi, M. Margreiter, T. Benz

Collection of Transportation Research Procedia (2017).

Abstract
The rapid development of wireless communication and information technologies has increased research interests in inter-vehicle communication systems and their effect on traffic flow. One of the most complex traffic phenomena on freeways are shockwaves. Shockwaves are recognized as the sudden, substantial change in the state of the traffic flow, which acts as an active or moving bottleneck. They have significant impact on freeway capacity and safety. For this study, a microscopic traffic simulation was used to determine the extent to which inter-vehicle communication and change in the driving strategy after the recognition of a shockwave can influence the propagation and dissolving of shockwaves on freeways. We also briefly introduce the shockwave theory and our communication algorithm. Then we present the simulation result with different penetration rates of communicative vehicles, which are randomly dispersed in traffic flow, through performance measures for trafﬁc ﬂow with shockwaves.
Abstract
The rapid development of wireless communication and information technologies has increased research interests in inter-vehicle communication systems and their effect on traffic [...]
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An Analysis of Heavy Vehicle Impact on Roundabout Entry Capacity in Japan
N. Kang, H. Nakamura

Collection of Transportation Research Procedia (2017).

Abstract
Heavy vehicles behave differently from ordinary passenger cars due to their characteristics such as size and operational performance. At roundabout, entry capacity estimation mainly focuses on passenger cars. In HCM 2010, the impact of heavy vehicles on entry capacity is considered through a heavy vehicle adjustment factor fHV which includes heavy vehicle percentage and passenger car equivalent (PCE hereafter) value. It is generally set as 2.0, which means a heavy vehicle is assumed to be equivalent to two passenger cars. In existing methods, the PCE value at roundabouts is estimated based on several considerations such as entry capacity and move-up time. All of these considerations are influenced by local driver behavior and geometry conditions. Thus, this paper aims to estimate entry capacity considering the characteristics of heavy vehicle behavior in Japan. In this paper, characteristics of heavy vehicle behavior such as speed and gap parameters are firstly analyzed by using data observed at several roundabouts in Japan. Then, a simulation study which is calibrated based on the observation data is conducted by applying VISSIM 5.40. Roundabout entry capacity is estimated through assuming different heavy vehicle percentage values of each entry. Based on the estimated results of entry capacity, PCE value is calculated. The PCE values from the simulation study are compared with those values adopted by several design guidelines. Through the empirical analysis, it is found that heavy vehicles move in lower speed than passenger cars in the process of travelling roundabouts. The headways which are formed by heavy vehicles are commonly greater than those only formed by passenger cars. Then, PCE values which are calculated from simulation output are shown to change with different combinations of heavy vehicle percentage of each entry. The results in this paper provide a reference for roundabout entry capacity estimation considering heavy vehicle behavior in Japan. Future works are some further analysis from the viewpoint of geometry, since heavy vehicle behavior is significantly influenced by roundabout geometry such as inscribed circle diameter and circulatory roadway width, particularly at compact roundabout which is often the case in Japan.
Abstract
Heavy vehicles behave differently from ordinary passenger cars due to their characteristics such as size and operational performance. At roundabout, entry capacity estimation [...]
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A Rationale for Enhancing the German Highway Capacity Manual to Incorporate Oversaturated Freeway Facility Analysis
M. Hartmann, P. Vortisch

Collection of Transportation Research Procedia (2017).

Abstract
Unlike the U.S. 2010 Highway Capacity Manual, the most recent edition of German Highway Capacity Manual does not include methodology to evaluate the facility within oversaturated time periods. To incorporate this traffic flow regime within the methodology, we identify several aspects of the methodology that require enhancements and propose modifications. Next, we implement these modifications in a macroscopic traffic model developed as a software implementation of the German guideline. In this manner, the HBS user can conduct traffic flow analysis that includes volume-to-capacity ratios above 1.00 which has not been foreseen by the guideline until now. The main contribution of this paper is the identification of methods within the German Highway Capacity Manual that require modification to enable incorporation of oversaturated traffic flow within the analysis. Further, we introduce traffic density as a variable within the HBS methodology and show benefits of its incorporation during the oversaturated time periods. Finally, the paper includes illustrative examples of empirical and model-based evaluation of congested freeway facility in Germany. The paper concludes with a discussion of proposed methods and their limitations.
Abstract
Unlike the U.S. 2010 Highway Capacity Manual, the most recent edition of German Highway Capacity Manual does not include methodology to evaluate the facility within oversaturated [...]
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Capacity and Operational Improvements of Metering Roundabouts in Spain
M. Martin-Gasulla, A. Garcia, A. Moreno, C. Llorca

Collection of Transportation Research Procedia (2017).

Abstract
Roundabouts show great advantages due to their geometry and their priority system, both in terms of capacity and road safety, compared to other intersections. However, unbalanced flows may be a problem even at medium demand levels. One single approach may cause queues on the downstream approaches as drivers are not allowed to entry the roundabout. If that downstream approach has the highest flow demand, average delay is highly increased, so, the roundabout can be collapsed. This operational problem is derived from one of roundabouts fundamental properties: movements with greater traffic demand cannot be prioritized, unlike signalized intersections. A few solutions may be found, but the most cost-effective measure is traffic regulation by metering signals. The aim of the research is to analyze capacity improvements and operational performance on roundabouts with metering signals using traffic microsimulation, for Spain local conditions. Metering signals are based on creating gaps in the circulating stream in order to alleviate excessive delays on the main approach of the roundabout. Consequently, they are used only on heavy demand conditions during peak hours. On the metered approach, which causes problems for a main downstream approach (controlling approach), metering signals are implemented. The metered approach is stopped by red signals controlled by a queue detector on the controlling approach. So, the controlling approach is benefited by metering signals as drivers can easily enter the roundabout, and the roundabout overall traffic operation is improved. The research was conducted in 5 stages: roundabouts selection, field study, calibration and validation of a traffic microsimulation model in VISSIM, generation of multiple scenarios, and, analysis of the results. Two roundabouts with known unbalanced flow patterns on Valencia (Spain) were selected, traffic counts were carried out to describe their traffic flow patterns, which resulted on limited capacity at both locations. In order to quantify traffic operation improvement on metered roundabouts, a traffic microsimulation model in VISSIM was elaborated. The model was calibrated and validated using critical gaps, queues, delays, and speeds. Afterwards, a metering signal technique was implemented on VisVAP, based on an ad hoc signal control logic design. Almost 400 combinations of design and control metering signals parameters were required to obtain the optimal model (distances to yield line, red and green time settings) which presented the lowest average delay. It could be concluded that, for the same medium-high circulating flow, a higher demand would be able to enter the roundabout (of up to 80% from the controlled approach) with less average delay values (22% and 56% at each studied roundabout) by installing metering signals.
Abstract
Roundabouts show great advantages due to their geometry and their priority system, both in terms of capacity and road safety, compared to other intersections. However, unbalanced [...]
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Automatic Incident Detection Based on Bluetooth Detection in Northern Bavaria
M. Margreiter

Collection of Transportation Research Procedia (2017).

Abstract
This work describes an approach to determine the current travel times on freeways based on the detection and re-identification of Bluetooth devices onboard of vehicles using stationary roadside Bluetooth detection technology. It also aims at using this information for the traffic state determination of a whole freeway network with the goal of a fast and reliable dynamic net control in incident situations. Based on a four year experience in a Bluetooth detector test bed in Northern Bavaria, Germany, and after the evaluation of hundreds of millions of single detections, the technology as well as the developed algorithms for validation and evaluation of the data show their feasibility in practical use, especially in areas with a low density of stationary detectors like inductive loops. The data-driven part of the approach is divided into three subsequent steps. These steps are the determination of travel times, the data filtering and validation of plausible travel times and the automatic incident detection. The determination of travel time is based on the time stamp of the detection of a Bluetooth device with the shortest estimated distance to the position of the Bluetooth detector. For the data filtering the “Time Dependent Comparison to Neighbor Values Filter” will be applied. This filter allows for a fast and reliable differentiation between unrealistic (due to stops, detours, back and return trips etc.) and plausible travel time values for a certain segment of the freeway and is based on a method to validate if the determined travel time is in a plausibility threshold corridor defined by the values of the previous and the next neighboring travel times. The outcome is a detailed travel time information for the whole freeway network which is used for an automatic incident detection, which was developed and calibrated within this research project. This includes the detection of the start of an incident as well as the end of an incident. The result is continuous information about the prevailing travel times and a fast and reliable traffic state information for all segments, which allows for a dynamic large-scale re-routing in the Bavarian freeway network in case of congestions or other disturbances of the traffic flow.
Abstract
This work describes an approach to determine the current travel times on freeways based on the detection and re-identification of Bluetooth devices onboard of vehicles using [...]
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A Multi-modal Approach for Highway Assessment
M. Mailer

Collection of Transportation Research Procedia (2017).

Abstract
The paper is based on a project carried out to develop a new concept for the assessment of highway performance considering multi-modality, traffic management and ITS. Step by step a single-mode concept like it is used in the Austrian guidelines is extended to a multi-modal transport approach taking into account the capacity and quality of different modes on the road as well as in the corridor. By showing different options of meeting the quality target of road traffic this concept is aiming at a more efficient and cost effective use of traffic infrastructure and supporting the efficient allocation of limited funds. In order to allow for multi-modal considerations, transport demand has to be measured in persons and goods rather than in vehicle units. For the assessment of roads this combines the utilization of traffic capacity in terms of vehicles with the utilization of vehicle capacity in terms of occupancy and loading. So a multi-modal approach has to consider the characteristics and potentials of public transport on the road and of alternative means of transport in the corridor. The corridor comprises the road that has to be assessed as well as all parallel means of transport. The whole transport demand in passengers and goods using this corridor is taken into account. Corridor capacity results from the capacity of all means of transport. However, since the concept still focuses on the assessment of highway performance the transport contribution of the other means of transport is considered as reduction of the transport demand and hence of traffic load on the road. To finally assess the level of service on the road different criteria can be used. So the implications of using travel speed or reliability of travel time which is related to capacity utilization are discussed. Especially in hilly or mountainous regions a speed based assessment can result in problems due to unreasonable alignment and expensive road construction. Therefore the influences of different design parameters, horizontal alignment and grade as well as the traffic mix (proportions of heavy vehicles) on speed and capacity are analyzed in detail. The extended concept of road assessment is allowing multi-modal capacity utilization and capacity management to meet quality targets of road traffic. It supports the identification of different scenarios how transport demand can be accommodated adequately. It extends the range of suitable measures to respond to unsatisfactory quality of road traffic. Apart from road improvements it allows for management measures controlling a given demand rather than just accommodating it.
Abstract
The paper is based on a project carried out to develop a new concept for the assessment of highway performance considering multi-modality, traffic management and ITS. Step [...]
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Autonomous and Connected Cars: HCM Estimates for Freeways with Various Market Penetration Rates
L. Shi, P. Prevedouros

Collection of Transportation Research Procedia (2017).

Abstract
Major IT companies and vehicle manufacturers have announced their plans for autonomous driving technology. Autonomous light duty vehicles are often referred to as “driverless cars” (DLC). These technologies intend to partly or fully replace driving by combining navigation systems, artificial intelligence, in-vehicle sensors, roadside ITS and traffic monitoring data, vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications. The absence of perception errors and the minimal perception and reaction time of DLC enable them to maintain shorter headways, to apply consistent acceleration and deceleration rates, and to optimize the use of gaps. In theory, freeway operations and level of service (LOS) can be impacted to a substantial but yet unknown degree by the DLC. The Highway Capacity Manual (HCM).is a static and macroscopic methodology for assessing various traffic flow facilities. Its 2010 edition is not adjusted for the presence of DLC on highways, however, several of its parameters are sensitive to differences in perception and reaction times, headways, etc. An investigation was conducted to assess the likely changes to traffic flow characteristics that may result from the introduction of DLC. The focus of this paper is on expressways, that is, on HCM analyses of basic freeway segment and freeway weaving segment. DLC is able to increase capacity (c), the maximum service flow rate (MSFi), the adjustment factor for unfamiliar driver population (fP), passenger-car equivalent (PCE), and the proportion of heavy vehicles (PT). The combined benefits improve LOS. The results from the case studies show that the impacts of DLC on HCM parameters are tiny if the DLC have a very small market share. Two types of DLC are considered in this paper: Autonomous DLC, and Connected DLC with V2V and V2I. On a basic freeway segment the Autonomous DLC improves LOS from D to C when its share in traffic reaches 7%. The same case study shows that the Connected DLC improves LOS from D to C when its share in traffic reaches 3%.
Abstract
Major IT companies and vehicle manufacturers have announced their plans for autonomous driving technology. Autonomous light duty vehicles are often referred to as “driverless [...]
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A Study of Collision Risk Estimation and Users Evaluation at Merging Section of Urban Expressway in Japan
K. Suzuki, K. Imada, Y. Matsumura

Collection of Transportation Research Procedia (2017).

Abstract
For usability of urban expressway in Japan, there are some problems due to the limitation of spatial con-straint. As the result of the limitation, there are merging sections that do not have enough length and set a right-side entrance ramp which is connected to the passing lane, directly. Therefore, unfamiliar drivers such as female and/or elderly drivers are subjected to stress and aware of danger when they merge onto the expressway and it is necessary to measure these situations quantitatively from the viewpoints of both traffic conflict risk and users evaluation. The purpose of this study is to estimate collision risk by using Surrogate Safety Measure and evaluate Quality of Service for drivers at merging sections of urban expressway in Japan. We focused on each ve-hicle merging movements and traffic conflicts at three on-ramps, which has different geometries, by im-age processing technology. First, in order to elucidate the occurrences of collision risk in merging section, we analyzed the collision risk between a merging vehicle and a main lane vehicle by using the Possibility Index for Collision with Urgent Deceleration (PICUD) index. It is shown that the position of conflicts is affected by the amount of traffic volume. Second, we conducted discriminant analyses for the results of the PICUD estimation in order to reveal the influence factors of collision risk at each merging section. As the result of discriminant analyses, it is found that the percentage of merging position and traffic volume of main lane have a huge effect on collision risk for merging movement. In addition, both the percentage of heavy vehicles and the existence of other merging vehicle at a time trigger rear-end collision risk. Fur-thermore, we examined some countermeasures to reduce collision risk in objective merging sections by sensitivity analysis and proposed a Level of Service index which is based on the rank of rear-end collision risk considering users’ subjective evaluation.
Abstract
For usability of urban expressway in Japan, there are some problems due to the limitation of spatial con-straint. As the result of the limitation, there are merging sections [...]
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Methodology for Timing and Impact Analysis of Signalized Intersections
K. Bang, J. Wahlstedt, L. Linse

Collection of Transportation Research Procedia (2017).

Abstract
A detailed procedure for capacity analysis of signalized intersections was first produced in 1976 and presented at the TRB Annual meeting (Bang, Hansson, Peterson 1978). In the eighties computer aids (named CAPCAL) based on this methodology were developed including traffic as well as safety and emission performance measures for different types of at-grade intersections. Capcal has been continuously updated since then, the last version CAPCAL 4.1 was based on a major Swedish HCM project called METKAP 2009 – 2013. The theoretical basis for the calculation procedures as well as the software are still subject to revisions based on user inputs. National base parameters and other variables are also included in these updates. CAPCAL 4 also adds improved capabilities to visualize calculation results. The use of CAPCAL is mandatory in projects for the Swedish National Road Authority, and it is also commonly used by local authorities, consultants and universities in Sweden. The computational methodology for signalized intersections is based on an iterative process including the following functions for each calculation cycle:Determination of saturation flow for all types of unopposed or opposed discharge. Traffic flow distribution between lanes in the same sub-approach.Identification of the critical conflict point for traffic streams that are served by different main signal phases (Min∑_1^n▒q/s).Signal timing for minimum total delay or other object function.Determination of traffic performance at normal and oversaturated conditions Special consideration has been devoted to development of the following sub modules: Automatic calculation of inter-green times and minimum green periods which give instant feedback of geometry changes Short lane utilization and contribution to approach bottleneck capacity. Procedure for identification of the critical conflict point for complex intersection configurations and phase schemes including extra or alternative phases for efficient discharge of turning movements.Optimal signal timing including considerations to minimum green and lost time restraints Consideration of exit capacity Calculation of delay and other traffic performance variables for forcasted traffic flows including improved handling of oversaturation Linking of capacity model to existing modules for calculating impact on environment, costs and traffic safety. The method is limited to isolated intersections, and based on fixed timed signals. Impacts of Traffic Actuated signal control is approximated by signal timing corrections (max green, green time extension intervals) based on traffic simulation results for different types of control strategies. In further work those corrections will be enhanced and also include the impacts of bus priority in vehicle actuated signal control using a more complex probability based model.
Abstract
A detailed procedure for capacity analysis of signalized intersections was first produced in 1976 and presented at the TRB Annual meeting (Bang, Hansson, Peterson 1978). In [...]
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Effective Installation of an Auxiliary Lane at Sag Sections to Mitigate Motorway Traffic Congestion
J. Xing, J. Tanaka

Collection of Transportation Research Procedia (2017).

Abstract
1. Introduction & Objectives Traffic congestion has been an important social issue in all over the world. It will result in great economic loss due to time delay and environment deterioration. In Japan, traffic congestion on intercity expressways on weekends and holidays is not an unusual scene. Looking at the percentage of congestion occurring on Japanese intercity motorways by bottleneck type, nearly 80% occurs in uninterrupted flow sections of sags or uphill slopes (60%) and tunnel entrances (20%). Congestion at merge areas accounts for approximately 13%. At a high level of traffic flow before occurrence of congestion, there exists a difference of travel speed between outer lane and inner lane, eventually causing an increase in use of the inner lane. The resultant inequality of lane utilization results in a breakdown of traffic flow in the inner lane of multilane motorway while flow of the outer lane remains below its capacity, thus decreasing the directional capacity. Once congestion occurs at a bottleneck, capacity would drop from pre-queue breakdown flow rate to lower queue discharge flow rate during congestion. As a measure against congestion, queue discharge flow from a bottleneck could be increased by providing drivers with information on the location of the head of the queue using roadside VMS. It is also possible to correct the overuse of the median lane by adding an auxiliary lane around the bottleneck at a sag. Besides, correction of unbalanced lane use could also be achieved by the provision of traveller information, such as “Please keep left” or “Please use left hand lane” to drivers through the VMS before occurrence of the congestion, (care should be taken here that vehicles drive on the left in Japan). However, there is no guideline on effective addition of an auxiliary lane in sag section for mitigation of motorway traffic congestion. This paper uses a microscopic traffic simulation model to study the effective way of adding an auxiliary lane in sag section of a dual 2-lane motorway for mitigation of traffic congestion. 2. Results The study considers 2 types of auxiliary lanes in sag section, i.e. one diverging and merging from outside, and one diverging from inside and merging from outside. The length of auxiliary lane varies every 500m from 500m to 2, 000m. The auxiliary lane is added at various locations ending at or starting from the bottom of a sag, or starting from the start of a vertical curve, or starting from around the midpoint of upstream half of a vertical curve. Altogether 15 cases are considered for the simulation study. The microscopic traffic simulation model is used in the study. Prior to the simulation runs, some parameters are calibrated to check if the 5-min average speed and median lane utilization agree with the observed data. The spatial distribution of lane utilization before, inside and after an auxiliary lane is also examined. The output of the simulation runs in the study is breakdown flow rate for each case of auxiliary lane. It is seen from the simulation results that for an auxiliary lane diverging and merging from outside, the optimum length should be 1, 000m – 1, 500m and be added from around the start of vertical curve to several hundred meters beyond the end of vertical curve. This is in accordance with the observation that shock waves take place in the length of auxiliary lane of a sag section. The auxiliary lane longer than the optimum length does not seem to result in higher breakdown flow rate. With the same length of auxiliary lane, the one diverging from inside and merging from outside would yield higher breakdown flow rate than the one diverging and merging from outside from the viewpoint of increasing the breakdown flow rate.
Abstract
1. Introduction & Objectives Traffic congestion has been an important social issue in all over the world. It will result in great economic loss due to time delay and environment [...]
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Intelligent Controlled Compact Parking for Modern Parking Management on German Motorways
J. Dierke, J. Kleine, R. Lehmann

Collection of Transportation Research Procedia (2017).

Abstract
The high density of commercial freight transport on motorways makes it difficult for truck drivers to find safe parking places especially for longer rest periods during the night. Even though expansions have been made to satisfy the demand in Germany, overcrowding and dangerous situations still occur as a result of vehicles parking on the entrance and exit roads of rest areas. In 2005 a control procedure called “Convoy Parking” was installed at the rest area Montabaur on the A3 motorway in Germany. Convoy Parking is subject to a patent (EP 1 408 455 B1, 2007). Convoy Parking requires all drivers entering their departure time at a terminal in front of a barrier. Subsequently, on the basis of the input data, the automatically detected vehicle length and the actual situation at the rest area, a free parking row is assigned and trucks can be parked sorted. The German Federal Highway Research Institute (BASt) developed a new control procedure called “Intelligent Controlled Compact Parking” (hereafter referred to as “Compact Parking” for short) to achieve that trucks are parking in a compact way, side by side and without a driving lane between trucks. Convoy Parking and Compact Parking have a very different control procedure and appearance. While Convoy Parking assigns a parking row to the driver, Compact Parking deliberately leaves the choice of the parking row to the drivers themselves. Drivers do not have to disclose their departure time to any system and they are not stopped by any barrier because Compact Parking offers a wide range of departure times on variable message signs. Drivers ought to use the parking row where their intended departure time is offered. With the innovative system Compact Parking the capacity of an existing rest area can be quickly increased without enlarging the area. This also avoids long-term planning approval procedures and is friendly to the environment. Besides, the safety for all users of the rest area can be improved by reducing illegal parking. Compact Parking is supported by the German Federal Ministry of Transport and Digital Infrastructure (BMVI). The first installation of Compact Parking is under construction at the rest area Jura-West on the A3 motorway (Northern Bavaria). The Autobahndirektion Nordbayern (Motorway Directorate for Northern Bavaria) is the central agency to plan, build and run the motorways in Northern Bavaria and got the approval of the BMVI to realize the pilot project. BASt accompanies the pilot project and leads the implementation of the control procedure. The opening is scheduled for summer 2015.
Abstract
The high density of commercial freight transport on motorways makes it difficult for truck drivers to find safe parking places especially for longer rest periods during the [...]
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Variability of Capacity and Traffic Performance at Urban and Rural Signalised Intersections
J. Chodur, K. Ostrowski, M. Tracz

Collection of Transportation Research Procedia (2017).

Abstract
Urban and rural intersections differ in terms of functionality. They support traffic which differs in terms of travel goals and motivations. In urban areas, these goals are mainly related to work, home, shopping and recreation. On the other hand, rural intersection mainly support through traffic between towns and cities and regions, with a small admixture of local traffic. Comparison of the characteristics of traffic flows indicates that towns and cities have heavier traffic flows, mainly of light vehicles, and frequent congestion states, while rural areas reveal smaller traffic flow and its structure is more diverse and involves vehicles travelling at higher speeds. The structure of traffic directions at rural intersections, usually dominated by traffic moving along one of the intersecting roads, differs substantially from the structure of the same at urban intersections. In order to control traffic, rural intersections increasingly rely on varied in time traffic signals, with a preference strategy whenever there is absence of excitation of motion detectors by the participants. The scope of intersections expansion and traffic control algorithms are more varied at urban intersections. Rural intersections are mainly controlled based on three major driving phases. Differences in intersections locations and the specificity of traffic conditions and traffic control imply drivers’ different needs and behaviour. Hence it is important to conduct comparative analyses of urban and rural intersections. The paper will present analysis of variability of saturation flows and capacity and traffic performance based on empirical studies of intersections in 2008 – 2012, both in urban and rural areas. Differences in drivers’ needs and behaviour in rural areas, the specific distribution of types of vehicles and directions on the lanes (single carriageway and dual carriageway) translate into slower vehicle service processes. Smaller values of saturation flow and capacity in rural areas mean that significant periodic increases in traffic flow lead to congestion states much faster than in urban areas. Although in rural areas these states are rather rare for the main direction, they are much more common at entries to the main road. The seasonal variability of traffic makes the functioning of these intersections differ between business (non-recreational) and recreational traffic (e.g. during the holiday season). The paper will also address the issue of acceptance of difficult traffic conditions in the states of traffic overload from the point of view of the road managers and the driver, referring to the reliability of intersection entries in urban and rural areas.
Abstract
Urban and rural intersections differ in terms of functionality. They support traffic which differs in terms of travel goals and motivations. In urban areas, these goals are [...]
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A Prediction Accuracy-Practicality Tradeoff Analysis of the State-of-the-art Safety Performance Assessment Methods
J. So, S. Hoffmann, J. Lee, F. Busch, K. Choi

Collection of Transportation Research Procedia (2017).

Abstract
This study proposes advanced safety assessment methods in the perspectives of prediction performance and practicality. This study thus develops three different safety assessment approaches (simulated conflicts-incorporated, estimated conflicts-incorporated, and intersection operational attributes-based safety performance function) and utilizes two existing approaches (annual average daily traffic-based and simulated conflicts-based safety performance functions. These five safety assessment approaches are compared in terms of crash prediction performance at intersections and practicality representing the required efforts in implementing a method. The results showed that the simulated conflicts-incorporated safety performance function approach was best in terms of prediction performance while the annual average daily traffic-based safety performance function approach was best in the practicality aspect. The discussion on trade-off between prediction performance and practicality then followed based on the analysis on the prediction performance and practicality aspects. This study will be a reference to safety assessment practitioners when they need to assess safety on roadways and to select an appropriate safety assessment method with limited resources.
Abstract
This study proposes advanced safety assessment methods in the perspectives of prediction performance and practicality. This study thus develops three different safety assessment [...]
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Estimation Method for Interurban Accessibility: A Highway Performance Measure Indicating Smooth and Safe Traffic Flow
H. Kita, H. Yotsutsuji, R. Asaka, J. Tsujitani, T. Watanabe

Collection of Transportation Research Procedia (2017).

Abstract
Developing driver-oriented highway performance measures is the key to performance-based highway design. Highways should be designed so that an appropriate performance measure corresponding to major highway functions can achieve a required level of quality of traffic service. Quantitative assessments of performance measures need to evaluate the achieved level of performance as compared with the required level. Various measures have been proposed, such as overall travel speed, target travel speed, travel time, traffic safety, traffic density, congestion, freedom to maneuver, and driving comfort and convenience (HRB, 1965, TRB, 1985, FGSV, 1988). However, it is unclear how existing performance measures relate to driver perceptions of the quality of traffic service. This study focuses on ease of access to destinations as a new driver-oriented performance measure under various driving conditions on interurban expressways connecting hub cities. This measure indicates the ease of maintaining vehicle speed near a target travel speed while maintaining a constant headway in the lane. We hereinafter refer to this measure as “interurban accessibility.” Interurban accessibility can be expressed as the sum total of utility that each driver perceives from smooth and safe traffic flow at each point in interurban expressway lanes. The objectives of this study are twofold. One objective is to develop an estimation method for interurban accessibility based on driver utility as proposed by Kita et al. (2014) . Their experimental results indicate that our proposed measure more appropriately describes driver perceptions of the quality of traffic service than do previously proposed performance measures. The other objective is to demonstrate how to use interurban accessibility to determine the planning level of the performance measure in comparison with a required level of quality of traffic service. In modeling the interurban accessibility measure, the level of interurban accessibility decreases as travel time between hub cities increases or as freedom to maneuver decreases because of congestion and delays. Hence, our model of interurban accessibility assumes a target travel time, defined as the travel distance divided by the target travel speed, so interurban accessibility is presumed to increase with travel speed. In addition, Kita and Kouchi (2011) showed that perception structures of interurban accessibility are momentarily formed by accumulating perceived values. Hence, our model involves both average and minimum point-based utilities in microscopic driving environments, so that accident risks contingent on speed can be considered for each point-based utility. Moreover, accumulation of point-based utilities between hub cities is considered to exert a decisive influence on the level of interurban accessibility. Driver memory is assumed to decay over elapsed driving time. Hence, accumulated point-based utilities are multiplied by a time discount factor, so that average point-based utilities are obtained to average the discounted point-based utilities. This study proposes a method for assessing the planning level of performance measures by means of an interurban accessibility estimation model, as compared with a required level of quality of traffic service. We therefore utilize exceedance probability of a probability distribution function regarding interurban accessibility. Note that, regarding traffic management and control through the use of a highway performance measure, it is believed to be better to apply data from roadside continuous-traffic-monitoring devices. Therefore, this study proposes a method for assessing interurban accessibility by examining traffic volume, which is easy to observe at each device. Before assessing the planning level of the measure as compared with the required level, the distribution of the interurban accessibility measure must be particularized. We presents a flowchart for specifying the distribution of a measure. The procedure of this flowchart requires a probability distribution of instant utility and a probability distribution of difference in instant utility between two points. The former requires distributions of time headway and spot speed, and the latter requires microscopic driving environments such as space headway that each driver perceives. Both the former and the latter require data on traffic volume and travel distance. The travel distance here means a given highway distance between hub cities. The distributions of the time headway and spot speed are affected by traffic characteristics such as road gradient and large-vehicle mix rate, in addition to the traffic volume. The following describes the procedure of the proposed flowchart. Firstly, assuming that the distribution of the time headway and that of the spot speed can be approximated by a log-normal distribution and a normal distribution, respectively, data on both the time headway and the spot speed are generated. Secondly, assuming that the distribution of the instant utility and that of the difference in instant utility between two neighboring points can be approximated by a shifted log-normal distribution and a Cauchy distribution, respectively, data on both the instant utility and the difference in instant utility between two points are generated. Thirdly, according to the point-based utility model, the number of point-based utilities for each point is generated based on Monte Carlo simulation employing both the distribution of the instant utility and that of the difference in instant utility between two points. Finally, a distribution of the interurban accessibility can be obtained from the interurban accessibility estimation model. Here, as a critical value indicating an exceedance probability of 85% in this distribution, a planning level of the performance measure is considered. Through a numerical example, we confirmed that the proposed measure can better describe driver perception than can existing measures such as travel speed. Consequently, we believe that performance-based highway design considering data obtained from vehicle detectors is possible by considering interurban accessibility as the performance measure.
Abstract
Developing driver-oriented highway performance measures is the key to performance-based highway design. Highways should be designed so that an appropriate performance measure [...]
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Recent Developments and History of the Dutch HCM
H. Heikoop, N. Henkens

Collection of Transportation Research Procedia (2017).

Abstract
Around 1995 the need for a Dutch Highway Capacity Manual (HCM) was felt within Rijkswaterstaat (Rijkswaterstaat is the executive body of the Dutch Ministry of Infrastructure and the Environment). Previously the American HCM was used, but specific circumstances in the Netherlands made it necessary to develop a Dutch HCM. This led to the introduction of the Dutch HCM, Handboek Capaciteitswaarden Infrastructuur Autosnelwegen in 1999, followed by the 2nd edition in 2002. Then, after a long period a completely new 3rd edition was published in 2011 and a fourth edition was completed in 2015. More than 15 years of research on highway capacities and the experience in using the manual has resulted in a practical handbook with an obligation to use it in planning studies for new and renewed highways in the Netherlands. The manual is one of the guidelines implemented in a working process system for planning studies. Although different indicators have been used over the years in transportation policy, the volume-to-capacity ratio is still the main indicator for the traffic flow quality in the Dutch HCM. Before the introduction of the Dutch HCM (< 1999) this indicator had been used most frequently. The most recent fourth version of Dutch HCM includes the research of capacities of tapers, cloverleaves, rush hour lanes and 4 lanes freeways. Weaving sections received special attention, as they are still simulated with the microsimulation model FOSIM. The new information was mostly added after requests of users. Because of a bigger role of consultants and less involvements of experts of Rijkswaterstaat in the highway designing process, guidelines become much more obligatory and nowadays contain specific minimum values and other specifications of the highway elements. Analysis has also been performed of capacity measurements at more than 200 locations. The influence of, among others, lane width, speed limit, absence of emergency lanes, tunnels and bridges have been analyzed. Also different road work configurations have been analyzed. The results from these analyses have been used in the fourth version of the Dutch HCM to state the influence of different infrastructure elements on the capacity and to validate and update previously stated values.
Abstract
Around 1995 the need for a Dutch Highway Capacity Manual (HCM) was felt within Rijkswaterstaat (Rijkswaterstaat is the executive body of the Dutch Ministry of Infrastructure [...]
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Traffic Flow at a Freeway Work Zone with Reversible Median Lane
H. Waleczek, J. Geistefeldt, D. Cindric-Middendorf, G. Riegelhuth

Collection of Transportation Research Procedia (2017).

Abstract
Work zones on freeways usually affect the quality of service for road users. Aiming to reduce traffic flow disruptions to a minimum, Hessen Mobil – Road and Traffic Management installed an innovative reversible lane system in a work zone on Autobahn A 3 south-east of Frankfurt, Germany. The section with three lanes and temporary hard shoulder running in both directions carries a high amount of commuter traffic with considerable fluctuations in peak traffic flow direction. During road works, four lanes in the peak direction and three lanes in the non-peak direction could be maintained through the use of a reversible lane system. The paper discusses the effects of the reversible lane system on traffic flow and road safety. Radar measurements revealed a maximum traffic volume of roughly 1500 veh/h on the reversible lane, which is around 25% of the total traffic volume during peak hours. The capacity of the work zone was estimated with the stochastic capacity estimation technique based on models for censored data. Compared with the capacity of the unaffected three-lane carriageway with temporary hard shoulder running, a decrease of the capacity by 14% to 17% was estimated for the four-lane work zone configuration including the reversible lane, depending on the direction. The difference between the capacities in both directions can be explained by the different lane geometries at the respective beginning of the work zone, leading to a higher number of lane changing manoeuvers directly upstream of the lane diverge in one direction. The traffic flow analysis also yielded a considerable impact of the work zone on peak hour traffic demand volumes, which were reduced by approximately 1000 veh/h. Similar to other freeway work zones, the road safety analysis revealed an increase of accident rates during road works. However, based on police accident reports only 10% of the total number of accidents and none of the severe accidents could be linked to particular features of the reversible lane system. Altogether, the investigation shows that a reversible lane system is a useful, safe and accepted instrument of intelligent traffic management for freeway work zones with high fluctuations in peak traffic flow direction. At the analyzed work zone, estimated travel time losses of 400000 veh*h could be saved during two months of road works by the application of the reversible lane compared with a permanent lane reduction in one direction.
Abstract
Work zones on freeways usually affect the quality of service for road users. Aiming to reduce traffic flow disruptions to a minimum, Hessen Mobil – Road and Traffic Management [...]
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Capacity and Behaviour on One-way Cycle Tracks of Different Widths
P. Greibe, T. Buch

Collection of Transportation Research Procedia (2017).

Abstract
The main objective of this study is to examine how widths of cycle tracks influence the behaviour, flow and capacity of bicycle traffic. Empirical data has been collected by video observations at 8 different cycle tracks of varying widths (1.85m-2.85m excl. kerb between cycle track and carriageway). The locations are characterised by high bicycle traffic volumes on the track, no traffic lights / junctions / bus stops / zebra crossing nearby, and no dividing verge between cycle track and carriageway. Speed and lateral positions has been measured for 8, 925 cyclists. The average speed is 21.6km/h but differs slightly between locations. Women ride 2-3km/h slower than men but also with a smaller dispersion. The traffic volume does not affect average speed, but dispersion decrease with increasing bicycle traffic volumes. At narrow cycle tracks cyclists are riding closer to the footpath and closer to each other during overtaking compared to cycle tracks of a larger width. Car parking in the road side next to the cycle track reduces “the effective width” of cycle track with about 10-15cm. High bicycle traffic volumes are only observed in short time spans and it seems like the capacity limit is not reached. Flows as high as 20 bicycles per 10 sec are observed at a 2-lane cycle track (width: 2.35m) and still with an average speed of about 21km/h. Controlling factors are used when calculating capacity from short time spans, and the hourly capacity of a 2-lane cycle track has been estimated to about 3, 000bicycles/h. The width does not affect the capacity much unless the number of lanes are reduced or increased. A cargo bike has an average speed of 16.3km/h and its headway is 1.3 times as big as the headway of a traditional bicycle. Due to the speed and the size of a cargo bike it reduces capacity equally to 3-4 traditional bicycles. Based on the data minimum and recommended widths of bicycle tracks are found.
Abstract
The main objective of this study is to examine how widths of cycle tracks influence the behaviour, flow and capacity of bicycle traffic. Empirical data has been collected [...]
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An Analysis of Express Lanes in Utah
G. Schultz, S. Mineer, C. Hamblin

Collection of Transportation Research Procedia (2017).

Abstract
This paper reports on an analysis conducted to identify ways to improve average speeds in the Express Lanes (ELs) in Utah. The research began with an investigation of the current usage of both the ELs and the General Purpose (GP) lanes by user type (e.g., single-occupant vehicle, high-occupancy vehicle (HOV) 2, HOV 3+, “C” decal, Express Pass user, motorcycle, bus, freight vehicle, and emergency vehicle) to better understand the breakdown of vehicles in the lanes and to calculate average vehicle occupancy. Violation data were examined to determine ways to reduce violator rates, while ways to control Express Pass traffic and to evaluate changes to toll rates and to estimate the impacts on speed of specific toll increases along the corridor were explored. The data collected were examined to better understand the speed-flow relationship on the ELs and to estimate the impact of volume changes on speeds in the lanes. This allowed the research team to estimate the impact on EL and GP lane volumes and speeds under a combination of EL education campaigns, increased EL enforcement, and increased EL peak period toll rates. Depending on the scenario analyzed, it was determined that the speeds in the ELs could be expected to increase as a result of the recommendations. The increase was found to be dependent upon the scenario chosen and the response of the traffic to the increases with an average maximum change in EL speed of 7.8 mph for a combination of education, enforcement, and increased tolls.
Abstract
This paper reports on an analysis conducted to identify ways to improve average speeds in the Express Lanes (ELs) in Utah. The research began with an investigation of the [...]
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Assessment of Basic Freeway Segments in the German Highway Capacity Manual HBS 2015 and Beyond
J. Geistefeldt

Collection of Transportation Research Procedia (2017).

Abstract
The second edition of the German Highway Capacity Manual HBS was published in 2015. The paper presents the HBS procedure for the assessment of basic freeway segments and discusses challenges for the future development of the methodology. As in the former edition of the HBS, the volume-to-capacity ratio is used as measure of effectiveness for basic freeway segments. The design capacities and speed-flow diagrams for basic freeway segments were completely revised and supplemented by new design values for segments with four-lane carriageways and segments with hard shoulder running. Besides the provision of specific design capacities, the reduced capacity variance on segments with variable speed limits, which was ascertained in recent investigations, is considered by adjusting the lower threshold value of LOS E. The new edition of the HBS also provides a framework for the use of specific parameters and the application of alternative methods for the assessment of traffic flow quality. Overall, the revised procedure for the analysis of basic freeway segments includes major enhancements and covers a larger number of segment types, but the main concept still follows the tradition of using deterministic capacities and providing rather simple analytical procedures to assess the traffic flow in one specific peak hour. For the future development of the HBS, the application of computer-based simulation models as well as the use of stochastic traffic flow parameters that better represent traffic reliability will increasingly emerge.
Abstract
The second edition of the German Highway Capacity Manual HBS was published in 2015. The paper presents the HBS procedure for the assessment of basic freeway segments and discusses [...]
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Evaluation of Driver Compliance to Displayed Variable Advisory Speed Limit Systems: Comparison between Germany and the U.S.
G. Riggins, R. Bertini, W. Ackaah, M. Margreiter

Collection of Transportation Research Procedia (2017).

Abstract
Variable Speed Limit (VSL) and Variable Advisory Speed (VAS) systems are applications of a growing field of active traffic management systems (ATM). This technology aims to improve safety while reducing congestion and emissions. VSL is common on German freeways, harmonizing traffic flow during congestion and weather events. Portland, Oregon installed a VAS system (advisory meaning it is not automatically enforced) on an eleven km (7 mile) segment of heavily congested urban freeway. The Portland region maintains archived, high-resolution data of both VAS sign messages and speed detection loop feedback, permitting reconstruction of traffic and sign data. This work analyses over 30 days of archived data from the Portland site in order to study driver compliance to the VAS signs. The focus is to suggest methods and parameters to score system performance. Such an analysis could benefit new rollouts of VAS corridors by providing system performance feedback and shed light on options for improving system performance.
Abstract
Variable Speed Limit (VSL) and Variable Advisory Speed (VAS) systems are applications of a growing field of active traffic management systems (ATM). This technology aims to [...]
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Evaluating the Service Quality in Multi-modal Transport Networks
M. Friedrich

Collection of Transportation Research Procedia (2017).

Abstract
The German Highway Capacity Manual HBS (Handbuch fuer die Bemessung von Strassenverkehrsanlagen, FGSV 2015) like other Highway Capacity Manuals provides a collection of methods for evaluating the Level of Service for single road facilities, i.e. a particular network element like a road segment, a ramp, or an intersection. The Level of Service of single road facilities (LOS) is derived from the volume capacity ratio, the delay time or the traffic density. In addition to the HBS the German guidelines provide a complementary Guideline for Integrated Network Planning RIN (Richtlinien für die integrierte Netzgestaltung, FGSV 2008) which is used for categorising transport networks and for evaluating the service quality in multi-modal networks. Here the LOS refers to entire journeys, i.e. to origin-destination-pairs. The most important indicator for evaluating the service quality of a particular od-pair is the direct speed (= direct distance / journey time). Journey time and the resulting direct speed include not only the in-vehicle time but also access and egress times which can reduce the speed of the entire journey significantly, especially in public transport. Additional indictors evaluation the directness and the travel time ratio of competing modes complement the set of indicators for evaluating the service quality. For each indicator the guideline provides evaluations functions for the service levels A to F which depend on the direct distance between origin and destination. This reflects the fact that speeds typically increase with longer distances while detour factor and travel time ratio decreases. The paper summarizes the approach of the guideline for evaluating the service quality and presents experience with the evaluation scheme collected in various applications covering car and public transport networks. It shows how the evaluation results can be used to recognize shortcomings in the network not only on the level of od-pairs but also to identify critical network elements. Finally the paper explains how the two guidelines HBS and RIN are connected.
Abstract
The German Highway Capacity Manual HBS (Handbuch fuer die Bemessung von Strassenverkehrsanlagen, FGSV 2015) like other Highway Capacity Manuals provides a collection of methods [...]
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Spatio-Temporal Congestion Patterns in Urban Traffic Networks
F. Rempe, G. Huber, K. Bogenberger

Collection of Transportation Research Procedia (2017).

Abstract
Traffic congestion in urban areas is a big issue for cities around the world. Thus, studying congestion and respective counter measures is of high importance for the increasing urbanization of society. Congestion analysis and forecast is most of the times done either on a link-wise network or on a network-wide level. Though, due to bottlenecks in the infrastructure and similar commuting patterns by road users, usually the same parts of an urban traffic network get congested. The idea is to observe and investigate primarily these most vulnerable parts of the network, which are denoted as congestion clusters, as they are crucial to both, drivers and operators. A methodology for determining congestion clusters is described, which provides a significant amount of flexibility to be able to meet different needs for different applications or cities. Based on a five months set of Floating Car (FC) data, the suggested methodology is tested. First analyses are conducted to understand up to which degree these clusters are able to represent the congestion level of the entire network. Besides, correlations between the clusters are investigated on a statistical basis and conclusions are drawn. The results provide a basis for potential traffic estimation and forecast systems.
Abstract
Traffic congestion in urban areas is a big issue for cities around the world. Thus, studying congestion and respective counter measures is of high importance for the increasing [...]
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Investigation of Automated Vehicle Effects on Drivers Behavior and Traffic Performance
E. Aria, J. Olstam, C. Schwietering

Collection of Transportation Research Procedia (2017).

Abstract
Advanced Driver Assistance Systems (ADAS) offer the possibility of helping drivers to fulfill their driving tasks. Automated vehicles (AV) are capable of communicating with surrounding vehicles (V2V) and infrastructure (V2I) in order to collect and provide essential information about the driving environment. Studies have proved that automated driving have the potential to decrease traffic congestion by reducing the time headway (THW), enhancing the traffic capacity and improving the safety margins in car following. Despite different encouraging factors, automated driving raise some concerns such as possible loss of situation awareness, overreliance on automation and system failure. This paper aims to investigate the effects of AV on driver’s behavior and traffic performance. A literature review was conducted to examine the AV effects on driver’s behavior. Findings from the literature survey reveal that conventional vehicles (CV), i.e. human driven, which are driving close to a platoon of AV with short THW, tend to reduce their THW and spend more time under their critical THW. Additionally, driving highly AV reduce situation awareness and can intensify driver drowsiness, exclusively in light traffic. In order to investigate the influences of AV on traffic performance, a simulation case study consisting of a 100% AV scenario and a 100% CV scenario was performed using microscopic traffic simulation. Outputs of this simulation study reveal that the positive effects of AV on roads are especially highlighted when the network is crowded (e.g. peak hours). This can definitely count as a constructive point for the future of road networks with higher demands. In details, average density of autobahn segment remarkably improved by 8.09% during p.m. peak hours in the AV scenario, while the average travel speed enhanced relatively by 8.48%. As a consequent, the average travel time improved by 9.00% in the AV scenario. The outcome of this study jointly with the previous driving simulator studies illustrates a successful practice of microscopic traffic simulation to investigate the effects of AV. However, further development of the microscopic traffic simulation models are required and further investigations of mixed traffic situation with AV and CV need to be conducted.
Abstract
Advanced Driver Assistance Systems (ADAS) offer the possibility of helping drivers to fulfill their driving tasks. Automated vehicles (AV) are capable of communicating with [...]
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Evaluating Driver Distraction Factors in Urban Motorways. A Naturalistic Study Conducted in Attica Tollway, Greece
E. Misokefalou, F. Papadimitriou, P. Kopelias, N. Eliou

Collection of Transportation Research Procedia (2017).

Abstract
Over the last years, distracted driving possesses a leading position among accident causes and it constitutes an increasing road safety problem with disastrous results. Considering external factors of distraction as highly significant, they can be grouped in four categories: built roadway, situational entities, natural environment, and built environment. The fourth category, related to civil infrastructure and commercial land use, combined with high vehicle speeds that occur in motorways, might contribute to the creation of a very dangerous environment, increasing driver distraction and inattention. Through accurate research, solid results can emerge and traffic safety can be enhanced. The present study deals with driver distraction caused by out-of-the-vehicle factors, as well as factors related to the driver, such as age, gender, driving experience etc. It covers the distraction of driver attention during driving due to external factors that are not related to the main task of driving, resulting in impairments to driver attention and decision-making ability and hence the driver’s overall performance. For this purpose, we assess the side effects of numerous road elements, such as information signs, roadside advertising, Variable Message Signs, toll buildings, noise barriers/panels etc. to driver attention. The study is based on a medium-scale experimental procedure which took place in Attica Tollway, the Ring Road of the Athens metropolitan area, which was part of a larger research project conducted by the University of Thessaly, Department of Civil Engineering that included a total of three urban freeways in Greece. In order to create the appropriate research basis and to use as reliable data as possible, the gaze tracker FaceLab software was used on a sample of 29 drivers. Each participant drove 51 km on Attica Tollway, both in level terrain with 3 lanes and speed limit up to 120 km/h and in rolling terrain with 2 lanes and speed limit up to 80 km/h. The distraction of driver attention is evaluated via a continuous recording of his/her gaze, which acts as the main indicator regarding driver performance. The results of this procedure, analyzed via Captive software, are focused on the time that the driver’s gaze remained on each of the road elements under research. The analysis offers conclusions on different aspects - driver, road element and the road in total - comparing and categorizing the results by using a 4-level timescale from 0 to 2 seconds. This study can be used as a tool that can help in understanding and limiting the use of roadside elements that are not related to the execution of the driving task, but that may serve as potential causes of distraction. The results of this type of research procedures are very useful in preventing the forthcoming pressure for more billboards and trademarks on the roads, as well as in encouraging the adaptation of more precise regulations relating to the road infrastructure, the placement of roadside elements, etc.
Abstract
Over the last years, distracted driving possesses a leading position among accident causes and it constitutes an increasing road safety problem with disastrous results. Considering [...]
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Data Fusion for ITS: Techniques and Research Needs
N. Faouzi, L. Klein

Collection of Transportation Research Procedia (2017).

Abstract
Intelligent transportation system (ITS) infrastructures contain sensors, data processing, and communication technologies that assist in improving passenger safety, reducing travel time and fuel consumption, and decreasing incident detection time. Multisource data from Bluetooth® and IP-based (cellular and Wi-Fi) communications, global positioning system (GPS) devices, cell phones, probe vehicles, license plate readers, infrastructure-based traffic-flow sensors, and in the future, connected vehicles enable multisource data fusion to be exploited to produce an enhanced interpretation of the monitored or observed situation. This occurs by decreasing the uncertainty present in individual source data. Although demonstrated for more than two decades, data fusion (DF) is still an emergent field as related to day-to-day traffic management operations. Data fusion techniques applied to date include Bayesian inference, Dempster-Shafer evidential reasoning, artificial neural networks, fuzzy logic, and Kalman filtering. This paper provides a survey of ITS DF applications, including ramp metering, pedestrian crossing, automatic incident detection, travel time prediction, adaptive signal control, and crash analysis and prevention, and indicates directions for future research. The encouraging results so far should not conceal the challenges that remain before widespread operational deployment of DF in transportation management occurs.
Abstract
Intelligent transportation system (ITS) infrastructures contain sensors, data processing, and communication technologies that assist in improving passenger safety, reducing [...]
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Assessment of Level-Of-Service for Freeway Segments Using HCM and Microsimulation Methods
D. Jolovic, A. Stevanovic, S. Sajjadi, P. Martin

Collection of Transportation Research Procedia (2017).

Abstract
The Highway Capacity Manual (HCM) 2015 freeway facilities methodology offers a supplemental computational engine FREEVAL, which is a macroscopic/mesoscopic tool that enables users to implement HCM-based freeway analysis quickly and conveniently. On the other hand, Vissim is a microscopic simulation tool that enables users to model real-world conditions with high level of accuracy and comprehensiveness. Thus, the two tools represent quite opposite sides in freeway modelling – Vissim requires time-consuming preparation and calibration of the model but it usually provides benefits that are more comprehensive. FREEVAL requires less on input and calibration sides but its results may not be as beneficial as comprehensive and accurate as Vissim’s. The problem, that has not been addressed enough, is that we do not know how different their results are (when compared between themselves) and, at the same time, how close to the field conditions. Researchers and practitioners use both tools for freeway analysis and tend to compare the results directly. One of the commonly used performance measures is the Level of Service (LOS), which is used to quickly evaluate the freeway segment or facility performance. The HCM Freeway Facility Methodology uses density to estimate LOS. However, density is calculated differently in FREEVAL and Vissim, and comparing the estimated LOSs between the two may not represent a proper comparison. In essence, FREEVAL, in the under-saturated condition, estimates the density from the fundamental equations where the volume is estimated from the user entered demand and the speed is calculated using the statistical models provided in respective chapters of each segment type. On the other hand, Vissim tracks each individual vehicle as it moves along a freeway and calculates key performance measures by using individually modeled driver’s behavior. This paper aims to compare and contrast the methodologies behind the two tools and offer explanation and discussion of their outputs. The paper will cover four major HCM freeway segment types (basic, merge, diverge, and weaving) in under-saturated conditions. Field data will be acquired from a section of I-880 freeway in California. FREEVAL and Vissim models will be calibrated and validated using Mobile Century Data provided by University of California at Berkley and Caltrans Performance Measurement System. The output of both tools will be evaluated against the field data. The assessment should reveal the ability of each tool to replicate the real-world conditions. Paper results will contribute to the existing body of knowledge by filling the gap in the literature related to comparison and contrast of the key (LOS-related) performance measures of these two tools.
Abstract
The Highway Capacity Manual (HCM) 2015 freeway facilities methodology offers a supplemental computational engine FREEVAL, which is a macroscopic/mesoscopic tool that enables [...]
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Capacity of Freeway Work Zones in Germany
N. Heiden, J. Geistefeldt

Collection of Transportation Research Procedia (2017).

Abstract
Work zones considerably influence the traffic flow quality on freeways. In work zones, the capacity can be significantly reduced due to narrower lanes, a reduced number of traffic lanes, and unfavorable roadway geometry. In order to evaluate the impact of work zones on congestion occurrence and resulting delays as well as to allow for a consideration of alternative work zone layouts in the planning process, models to estimate the capacity of work zones are required. The paper presents results from a comprehensive study of work zone capacity on German freeways. In the analysis, a large number of short-term work zones with temporary lane closures as well as long-time work zones with and without a reduction of the number of lanes were covered. Data from loop or radar detectors upstream of the work zones were analyzed. For the capacity estimation of long-term work zones, both deterministic and stochastic approaches were used. In contrast to long-term work zones, traffic flow data measured at short-term work zones include only one traffic breakdown observation in most cases. This breakdown often occurs immediately after the lane closure, which means that the pre-breakdown volume does not represent the capacity of the work zone. Hence, valid capacity estimates could only be determined for the post-breakdown congestion outflow. The estimated capacities were analyzed regarding the influence of the traffic, geometric and control conditions in the work zone. Relevant parameters are the number of lanes, the lane widths, the existence of divided lanes, the existence of a lane reduction as well as the share of commuters and heavy vehicles. For short-time work zones, also the side of the lane closure (left or right lane) has an influence on the capacity. As a result of the study, capacity estimation models for both short- and long-term work zones, which can be applied in work zone planning procedures, are provided.
Abstract
Work zones considerably influence the traffic flow quality on freeways. In work zones, the capacity can be significantly reduced due to narrower lanes, a reduced number of [...]
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A Model for Estimating Free-Flow Speed on Brazilian Expressways
G. Andrade, C. Pitombo, A. Cunha, J. Setti

Collection of Transportation Research Procedia (2017).

Abstract
Free flow speed (FFS) is defined in the HCM as the “average speed of vehicles on a given segment, measured under low-volume conditions, when drivers are free to travel at their desired speed and are not constrained by the presence of other vehicles or downstream traffic control devices”. FFS is a very important parameter for the estimation of LOS and capacity for uninterrupted highways facilities. Ideally, FFS is determined using field measurements, but the HCM 2010 provides models for its estimation, when field data is not available. Such models must be recalibrated for local conditions when the HCM 2010 is adapted for use in countries outside North America. In this paper, Multivariate Analysis (MVA) techniques are used to investigate which infrastructure characteristics are related to FFS on Brazilian expressway facility segments, in order to provide a framework for the development of models to replace those used in HCM 2010 to estimate FFS. This study used a database with a large number of speed-flow observations obtained at 36 sites on Brazilian expressways (freeways and divided multilane highways), along with information on seven variables describing segment characteristics such as: expressway type, roadside environment, number of lanes, rise and fall, bendiness, access point density, and posted speed limit for passenger cars. Principal Component Analysis (PCA) was used to select the variables to be included in the proposed model. The results of the PCA indicated that three components are responsible for most of the variance on observed FFS: (1) posted speed, (2) the combined effects of road class, number of lanes and density of access points, and (3) the interaction of geometric design and roadside environment. Stepwise linear regression was used to fit a FFS model from these three components. This model was mathematically manipulated to provide a FFS that is structurally similar to the one used by HCM 2010 but in fact accounts for the interactions among variables. The proposed model can replace the HCM 2010 model and does not require the user to choose an initial value for the base FFS.
Abstract
Free flow speed (FFS) is defined in the HCM as the “average speed of vehicles on a given segment, measured under low-volume conditions, when drivers are free to travel at [...]
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Proposed Data-Driven Performance Measures for Comparing and Ranking Traffic Bottlenecks
D. Hale, A. Hajbabaie, J. Ma, J. Hu, H. Park, J. Bared

Collection of Transportation Research Procedia (2017).

Abstract
To justify investments towards improved traffic operations, engineers and policy-makers need scientific and accurate methods of congestion measurement. However, status-quo methods are limited and/or outdated. Peak-hour analyses are becoming outdated as a sole source of traffic assessment, because they fail to account for changing conditions throughout the year. There has been a movement towards “reliability” modeling, which attempts to capture these annual effects. But due to significant input data and calibration requirements, the reliability models suffer from practicality issues. Next, there have been recent improvements in data-driven ITS technologies, which identify congestion in real time. However, there is room for improvement in the robustness of performance measures derived from these technologies. Finally, some engineers have compared and ranked congested locations (i.e., bottlenecks) on the basis of experience and judgment. Despite their cost-effectiveness, judgment-based qualitative assessments will lack credibility unless backed by quantitative results. In a recent Federal Highway Administration study, congestion measurement was a primary area of emphasis. This paper discusses project-specific software development, which produced new and innovative performance measures for congestion measurement. It will present concepts and evidence to imply superiority of the proposed new measures. This paper is intended to serve as a preview of a future full journal paper, which will rank ten or more real-world bottlenecks according to new and old performance measures, to demonstrate impacts of the new measures. It is hoped that the new performance measures will be adopted by states and/or commercial products, for a new level of robustness in congestion measurement.
Abstract
To justify investments towards improved traffic operations, engineers and policy-makers need scientific and accurate methods of congestion measurement. However, status-quo [...]
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Identification of Factors that May Affect the Discharge Flow at a Bottleneck
D. Yamaguchi, T. Okano, H. Sudo, M. Kobayashi, T. Ogihara, N. Izumi, A. Tanaka, T. Yoshii

Collection of Transportation Research Procedia (2017).

Abstract
This study investigates various factors that cause the reduction of discharge flow at a bottleneck on an urban expressway. The current worst bottleneck on Tokyo Metropolitan Expressway Network seems to be combined complicate factors that affect the discharge flow at the bottleneck. 5 causing factors, merging ratio, longitudinal gradient, duration time involved in congestion, environment of backlight and brightness are considered, and the impact of these 5 causing factors are investigated. Then the results supported the hypothesis that all of the 5 causing factors affect the discharge flow rate.
Abstract
This study investigates various factors that cause the reduction of discharge flow at a bottleneck on an urban expressway. The current worst bottleneck on Tokyo Metropolitan [...]
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Improving Traffic Flow at Long-term Roadworks
C. Schwietering, M. Feldges

Collection of Transportation Research Procedia (2017).

Abstract
Long-term roadworks on highways are vital as part of carriageway and bridge renovations. They generate bottlenecks and consequently congestion and accidents. If the number of lanes is reduced, it can also lead to significant capacity decrease. Even if it is ensured that all lanes are kept operative, narrow lanes and transitions will affect the capacity. The impact of roadworks on capacity have been analysed in detail by [BECK_2001]. Therefore, intelligent solutions to support the traffic flow at long-term roadworks bottlenecks have to be evaluated. For this purpose the TrafficChange concept was developed. TrafficChange describes the modules of tidal flows on long-term roadworks: - Module 1: Tidal Flow basic set - TrafficChange SE (quickly repositionable moveable safety barriers, so-called Quick-Change Moveable Barriers (QMB)) - Module 2: Attached Traffic Safety Equipment for Tidal Flow - TrafficChange VT including data collection, traffic monitoring, communication, energy supply and displays - Module 3: Repositionable congestion warning systems to safeguard congestion - Module 4: Core system for data analysis, monitoring and managing traffic (TrafficChange Center) as cloud-based service With these components, a dynamic assignment of lanes to higher demanded direction can be reached. Main application fields of TrafficChange are: - Maintenance of bridges - Renewal of road pavement, road surface restoration (entire carriageway) - Tunnel renovation with two-way traffic in the operational tube - Temporarily adaption of the number of operational lanes in dependency of the traffic demand in order to enlarge working space of a roadworks The use of TrafficChange has beneficial effects on capacity and thus on traffic flow. In case of traffic lane reduction due to roadworks, TrafficChange can dynamically assign the remaining traffic lanes according to the demand of both driving directions. Even if all traffic lanes are kept operational during the roadworks, TrafficChange provides several advantages. In case of roadworks on a six lane facility (three lanes in both directions), usually one lane has to be managed separately on the carriageway of the construction field. This has a massive negative impact on the roadworks progress and the completion timetable. When applying TrafficChange this single separate lane is not necessary. Simultaneously this leads to significant capacity increase for this lane, since all lanes are managed on one carriageway and overtaking opportunity is provided. Evaluations of roadworks in Germany have shown that using TrafficChange will enhance the capacity by 10-15% for the driving direction of the construction site. One the other hand, for the direction with low demand, capacity is reduced temporarily, since one lane less is available. When demand for this period is low and can be managed by using the remaining lanes, the traffic flow quality stays efficient. For an economically efficient use of TrafficChange, the demand peaks should not occur simultaneously in both directions. Therefore, for each roadworks it needs to be evaluated individually whether TrafficChange can efficiently improve the traffic flow. For evaluation of the effects, the TrafficChange system is implemented in a microscopic traffic simulation tool, which can be adapted easily for different settings of the roadworks to be evaluated. As input values, the number of available lanes, roadworks design, traffic demand for each required scenario (such as weekday, weekend, holiday) and the length and planned duration of the roadworks are required. As key values, the simulation determines the congestion length, congestion duration and delay times. With these values, the benefit of TrafficChange can be determined. The efficiency estimation is determined by accumulation of total delay times for each required scenario, multiplied by the amount of days this scenario occurs during the roadworks is active, for both the comparison case (roadworks without TC) and target scenario (roadworks with TC). By using current travel time expenses for passenger cars and heavy vehicles, the benefit can be expressed in costs. By the use of TrafficChange, the entire carriageway can be closed so that considerable savings of working period and economic losses could be achieved although the number of operative lanes is lower than in the comparison case. The TrafficChange concept leads to improved traffic safety and optimized traffic flow at roadworks as well as reduced roadworks duration and therefore high economic efficiency that can be determined by the simulation tool TCSim. Literature [BECK_2001] - Beckmann, A., Zackor, H. (2001): Study and calibration of procedures for current estimation of the duration and length of traffic jams as a result of single-day and long-term construction sites on motorways, Forschung Straßenbau und Straßenverkehrstechnik, Volume 808, Bonn, Germany, 2001 [EASY_2009] - Easyway (2009) : Mobile Congestion Warning Systems at lorm term roadworks increase traffic safety – Efficiency of Mobile Congestion Warning Systems, Offprint of the ‘Landestelle für Straßentechnik Baden-Württemberg’, Stuttgart, 2009, www.easyway-its.eu [SUEM_2012] - Sümmermann, A. (2012): Examination of traffic safety and traffic flow in work zones on German Motorways, Aachener Mitteilungen Straßenwesen, Erd- und Tunnelbau, Volume 59, Aachen 2012 [VOLK_2014] - Volkenhoff, T. (2014): Model-based derivation of operating conditions of a video-aided incident and work zone management system in construction sites on German motorways, Aachener Mitteilungen Straßenwesen, Erd- und Tunnelbau, Volume 61, Aachen 2014 [HMSV_2012] – HMSV (2012): Congestion Evaluation 2011. Hessen Mobil – Straßen- und Verkehrsmanagement. URL: http://www.staufreieshessen2015.de, requested on 04.07.2012
Abstract
Long-term roadworks on highways are vital as part of carriageway and bridge renovations. They generate bottlenecks and consequently congestion and accidents. If the number [...]
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Evaluation of Variable Speed Limit Pilot Projects for Texas Department of Transportation
B. Kuhn, K. Balke, R. Brydia, L. Theiss, I. Tsapakis, L. Ruback, M. Le

Collection of Transportation Research Procedia (2017).

Abstract
In May 2013, the regular session of the 83rd Texas State Legislature passed House Bill (HB) 2204 related to the establishment of a variable speed limits (VSL) pilot program by the Texas Transportation Commission. The bill was signed into law by the governor in June 2013. In December 2013, the Texas Transportation Commission established Rule §25.27 of the Texas Administrative Code authorizing and requiring the Texas Department of Transportation (TxDOT) to implement a variable speed limit pilot program to “study the effectiveness of temporarily lowering prima facie speed limits to address inclement weather, congestion, road construction, or any other condition that affects the safe and orderly movement of traffic on a roadway.” The goal of the pilot program was to deploy VSL in up to three locations to test the concept under three operational conditions and to determine the impacts of VSL on facility operations and safety. The specific objectives of the pilot project evaluation were to determine how much congestion was reduced in the area impacted by the implementation of VSL, to understand the users’ perceptions of the VSL systems, to assess the safety impacts of VSL, and to determine the overall costs and benefits of VSLs. Up until this point in time, VSL was not a legal alternative for freeway operations in Texas. After the bill was passed, TxDOT worked with the Texas A&M Transportation Institute (TTI) in selecting pilot project sites for the development, implementation, and evaluation of VSL. The VSL systems were to be used for the purpose of controlling speeds at sites that have (a) construction work zones, (b) weather-related events, and (c) urban congestion. This paper presents the overall approach to the development, implementation, and operation of the VSL pilot projects along with the analysis of the installations with respect to their impact on congestion, safety, users’ perception, violations, and benefit-cost of the projects. It also presents a number of lessons learned throughout the course of the pilot tests that provide beneficial insight into how to improve similar projects for permanent installations. Based upon the limited data available for the VSL pilot project, it was determined that VSLs would be beneficial if implemented to address inclement weather, congestion or road construction. VSLs had a safety benefit at each location and motorists had a clear understanding of the purpose of the VSLs.
Abstract
In May 2013, the regular session of the 83rd Texas State Legislature passed House Bill (HB) 2204 related to the establishment of a variable speed limits (VSL) pilot program [...]
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Safety of Characteristic Subsections of Roadwork Zones on Motorways
J. Bakaba, J. Ortlepp

Collection of Transportation Research Procedia (2017).

Abstract
Roadwork zones interrupt the flow of traffic and shall reduce road safety of motorways (autobahns), at least in specific sections. Motorways are the fastest roads in the German roadwork and have the highest level of safety – higher than either roads inside built-up areas or other roads outside built-up areas. Nevertheless, a total of 17, 172 accidents involving personal injury occurred on motorways in the year 2011, 1, 118 of them at roadwork zones. A total of 18 people were killed and 220 seriously injured. The principal aim of this research project was to find out if either roadwork zones on motorways are more unsafe than other motorways sections or they are specific subsections inside of roadwork zones or near them which are particularly unsafe. The research project consisted of an analysis of the statistics in the vicinity of all roadwork zones on German motorways (autobahns). Road accidents recorded by the police for a period of at least 12 months at 76 selected roadwork zones and a retrospective accident analysis of 12 completed motorway roadwork zones were macroscopic analyzed. In addition, a microscopic analysis of the accident occurrence was carried out of eight existing roadwork zones with a total length of 57 km and included also the analysis of the driving behavior of car and truck drivers throughout the length of the roadwork zones and/or in characteristic subsections in or near them. The results of the research project confirm that accidents at roadwork zones on motorways are generally accidents involving minor damage to property. The accident severity (fatalities per 1, 000 accidents involving personal injury) of accidents that occur on sections of motorway without roadwork zones is up to 1.6 times higher than that of accidents that occur at roadwork zones. The study shows different accident rates and accident cost rates for some characteristic subsections along the roadwork site. Nevertheless, there are problem areas in terms of road safety, particularly at the beginning and end of roadwork zones, lane realignment points, carriageway changeover points and temporary slip roads. These characteristic subsections of roadwork zones have an influence on the road safety. The same applies to the impact of how the traffic is routed, the length of the roadwork site or specific road equipment (e.g. road signs against a yellow background).
Abstract
Roadwork zones interrupt the flow of traffic and shall reduce road safety of motorways (autobahns), at least in specific sections. Motorways are the fastest roads in the German [...]
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Functionally Hierarchical Road Classification Considering the Area Characteristics for the Performance-oriented Road Planning
A. Goto, H. Nakamura

Collection of Transportation Research Procedia (2017).

Abstract
Functional hierarchy of road network classifies individual roads into several levels by taking account of the priority for mobility, access or residential functions, in order to manage traffic efficiently by segregating through traffic from accessing, parking and non-motorized traffics. This concept has been widely recognized and applied to road planning, design and operation in several countries such as Germany, the US and Australia. Their guidelines state the target performances (i.e., LOS or travel speed in general) of each hierarchical levels being used for the performance evaluation. However in Japan, target performances of roads are not shown in the current guideline, since a concept of the performance-oriented planning and design is still uncommon in practice. As a result, the operational performances are still not satisfactory enough especially on highways. In such a situation, this study attempts to find out the hierarchical road classification applicable to Japan, considering the distribution of region/district centers as well as the impact of terrain. The main questions are how many hierarchical levels need to be defined and how much travel speed and road spacing (or access distance) should be set as the targets for each level, so that the network performance, namely travel time between region/district centers, can achieve the given target values. The basic idea comes from the German guideline RIN, which states the target travel times by region/district center (central place), classifies roads and define their target travel speeds based on their connecting centers. However, it does not clearly mention how the difference in distribution of region/district centers and the impact of terrain can be reflected to set the efficient hierarchical classification. For example, the characteristic of metropolitan areas is quite different from that of mountainous areas in terms of trip lengths between region/district centers of which travel times are to be evaluated as network performance. In addition, because of the impact of terrain, construction cost per unit is generally quite higher in mountainous areas than in flat areas, whereas travel demand is usually lower in mountainous areas. This study incorporates these issues into road classification and demonstrates its impact for more efficient network system planning. The methodology consists of four steps: (1) defining the region/district centers to be connected and setting their target travel time, (2) developing alternative road classification scenarios, (3) mathematically formulating origin-destination travel time in a grid road network under the certain classification and (4) evaluating the classification scenarios considering the difference of average trip lengths of each combination of centers as well as the difference of system cost due to the impact of terrain and travel demand. Although the original intention of this study is to apply the result to Japan, the methodology itself is generally applicable to any region. At the end, case studies are conducted for several simplified areas for reflecting their typical characteristics of region/district centers distribution and terrain in Japan. Through them, the hierarchical road classifications by area type are suggested as a conclusion.
Abstract
Functional hierarchy of road network classifies individual roads into several levels by taking account of the priority for mobility, access or residential functions, in order [...]
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A Stochastic Car Following Model
A. Kendziorra, P. Wagner, T. Toledo

Collection of Transportation Research Procedia (2017).

Abstract
Car-following models are an essential part of microscopic traffic simulations. For research regarding traffic safety, traffic simulations need to simulate traffic safety related aspects realistically. That means, for example, accidents and near accidents shall occur in the same quantity and in the same way as in reality. Such simulations can be used to make statements about traffic safety with respect to traffic influencing factors and conditions. However, most car-following models are deterministic and do not incorporate uncertainty and fluctuations of perception and behavior. Also, they are explicitly conflict free. Therefore, they are unsuitable for simulating traffic in the desired way. For that reason, a car following model fulfilling the requirements above was developed. Inspired by [1], our car-following model is nondeterministic and data-driven. It is based on the data set of the Intelligent Cruise Control Field Operational Test [2], in which instrumented vehicles have been used by 108 voluntary drivers for several weeks yielding trajectories of approximately 88, 000 driving kilometres. In our model, the acceleration a of a vehicle depends on the following input: -v, the velocity of the vehicle, -∆v, the difference between the velocity of the preceding vehicle and its own velocity, -g, the gap between the vehicle and the preceding vehicle and -aL, the acceleration of the preceding vehicle. The acceleration a underlies a probability distribution that depends on v, ∆v, g and aL. That means, if v*, ∆v*, g* and aL* are the current values for v, ∆v, g and aL, then there exist a probability distribution F(v*, ∆v*, g*, aL*) and the actual acceleration a will be drawn from F(v*, ∆v*, g*, aL*). For each tuple (v, ∆v, g, aL), the probability distribution F(v, ∆v, g, aL) was determined by the data of the FOT. For that, the data of velocity, velocity difference, gap and acceleration of the preceding vehicle were binned, and for each tuple (v, ∆v, g, aL) of binned values, the expected acceleration, the variance and the type of distribution were computed and stored in look-up tables. During a simulation, the probability distribution F(v, ∆v, g, aL) to a given tuple (v, ∆v, g, aL) can be recovered by these look-up tables. To achieve probability distributions that result in a well behaving car-following model, the data had to be corrected (due to erroneous sensor data) and filtered (due to situations in which the driver reacted to other influences besides the preceding vehicle, e.g. red traffic lights) in numerous steps. Here, we will present the mentioned correction and filtering steps in detail. Further, we will discuss the derived probability distributions and the calibration of the model. Finally, the model will be evaluated and compared to other existing car-following models in several scenarios with respect to various criteria, e.g. the number of accidents, the distribution of surrogate safety measures, and the fundamental diagram.
Abstract
Car-following models are an essential part of microscopic traffic simulations. For research regarding traffic safety, traffic simulations need to simulate traffic safety related [...]
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Usage of Road Weather Sensors for Automatic Traffic Control on Motorways
A. Haug, S. Grosanic

Collection of Transportation Research Procedia (2017).

Abstract
Within section control systems on motorways drivers get information about adequate speed limits during adverse weather situations. Therefore road weather data are necessary. To detect the danger of aqua-planning measurements of precipitation intensity and waterfilm thickness as well as the status of the road surface are needed. To detect these atmospheric data different weather sensors are located near the motorway. There are two different sensor systems available which detect these measurements at the moment. For the detection of the status of the road surface, like dry, moist or wet, the sensor is imbedded directly in the road surface in most cases. The other sensor system is non-invasive which can be installed next to or over the road. Nowadays more and more open-pored asphalt is used because of its advantage to be less noisy and its property to drain off water better than normal asphalt. But this kind of asphalt cannot be cut to install a road sensor therefore the usage of non-invasive sensors will be increase in the future. This may also lead to different thresholds in automatic traffic control during adverse weather situations. The measurements of waterfilm thickness, road surface and road temperature are very important for automatic traffic control algorithms [2] as a speed limit caused by rain is derived and shown on variable message signs. In the German Technical Bulletin [2] a matrix with the two measurements precipitation intensity and water film thickness define which wetness-level is detected. There are 5 wetness-levels which cause different speed limits. For the first supply thresholds are given based on the experiences with road sensors. For the newer non-invasive sensors other thresholds may be necessary. This paper will show some possible thresholds for the precipitation/waterfilm thickness matrix and their effects on the speed limits shown on the variable massage signs. Within the German Test Site for Road Weather Stations [1] various road sensors as well as various non-invasive sensors are installed. The data for both detection technologies has been collected for the last 2 years and allows a statistically valid comparison of them. In this paper the advantage and disadvantage of the two sensor technologies will be shown for the measurements waterfilm thickness, road surface and road temperature. In order to describe the behavior of the sensors, the available data will be analyzed concerning the availability of valid datasets and the accuracy. Additionally the performance of the sensors is examined during periods of different clusters of traffic volumes.
Abstract
Within section control systems on motorways drivers get information about adequate speed limits during adverse weather situations. Therefore road weather data are necessary. [...]
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The Contribution of Ramp Demand in the Capacity of Merge Bottleneck Locations
A. Kondyli, P. Gubbala, L. Elefteriadou

Collection of Transportation Research Procedia (2017).

Abstract
Transportation engineers rely on the Highway Capacity Manual (HCM) for estimating capacity at freeway segments. According to the HCM 2010, the capacity of the basic freeway segments is a function of the free-flow speed and it ranges from 2, 400 passenger cars per hour per lane (pc/h/ln) for FFS 70 or 75 mi/h, to 2, 250 pc/h/ln for FFS 55 mi/h. The freeway merge segments methodology in the HCM 2010 Update uses these same capacity values in the analysis procedure, although research has shown that capacities at these bottleneck locations are considerably lower. In addition to that, researchers have also observed that capacity varies significantly from day to day and from one site to the other. Researchers acknowledge that driver behavior and frequent interactions between mainline and ramp vehicles at these junctions are the causal factor of these variations in capacity and the low capacity values, however, this has not been reflected in the updated version of the HCM 2010. Furthermore, the HCM 2010 Update does not account for the conflicting movements and the contribution of the ramp vehicles on the overall merge junction capacity. This paper investigates the relationship between freeway and ramp demand and capacity at merge junctions. For the purposes of this research, historic data at merge bottleneck locations across North America with different geometric and operational characteristics were analyzed. The results of the analysis show that, there is a clear correlation between ramp demand, freeway demand and freeway capacity. More specifically, higher demand on the on-ramps produces lower overall capacity values. In addition, this paper proposes new capacity values for merge junctions as a function of the freeway and ramp demand and number of lanes.
Abstract
Transportation engineers rely on the Highway Capacity Manual (HCM) for estimating capacity at freeway segments. According to the HCM 2010, the capacity of the basic freeway [...]
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Operational Analyses of Freeway Off-Ramp Bottlenecks
A. Skabardonis, F. Papadimitriou, B. Halkias, P. Kopelias

Collection of Transportation Research Procedia (2017).

Abstract
The paper presents the findings to date of operational analyses at freeway off-ramps with emphasis on analysis procedures on recurrent off-ramp bottleneck locations at the Attiki odos motorway (Attica Tollway) in Athens, Greece. We compared the observed traffic performance metrics at two sites with the predicted measures using the methodology of freeway diverge areas and weaving sections in the 2010 edition of Highway Capacity Manual (HCM) for a wide range of traffic conditions. The findings indicate that the HCM volume predictions at the diverge area are in close agreement with field data and the density is underestimated by 7% on the average. The HCM weaving analysis methodology underestimated the weaving section capacity especially for high weaving volumes, and overestimated the section density by 17% on the average.
Abstract
The paper presents the findings to date of operational analyses at freeway off-ramps with emphasis on analysis procedures on recurrent off-ramp bottleneck locations at the [...]
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Comparing Lane Based and Lane-group Based Models of Signalised Intersection Networks
R. Akcelik

Collection of Transportation Research Procedia (2017).

Abstract
This paper compares two analytical approaches for modelling signalised intersection networks in relation to the assessment of signal coordination quality as a fundamental element of network performance analysis. These are (i) the traditional model based on using “lane groups” or “links” through aggregation of individual lane conditions, and (ii) a new “lane-based” model of upstream departure and downstream arrival patterns as well as midblock lane changes between upstream and downstream intersections, and the resulting proportions of traffic arriving during the green period at an individual lane level. The latter is part of a lane-based network model that involves blockage of upstream intersection lanes by downstream queues (queue spillback) and capacity constraint applied to oversaturated upstream intersections. The differences between the two models are expected to be particularly important in evaluating closely-spaced intersections with high demand flows where vehicles have limited opportunities for lane changes between intersections. The lane-based model can make use of “special movement classes” (e.g. through movements at external approaches which become turning movements at downstream internal approaches, and the dogleg movements at staggered T intersections) to enhance the modelling of signal platoon patterns. This allows assignment of specific movements to separate lanes and separate signal phases, and tracking of their second-by-second platoon patterns through the network separately. The method also allows better estimation of unequal lane use cases at closely-spaced (paired) intersection systems, a factor which also affects signal platoon patterns. The paper presents a staggered T network example to demonstrate important aspects of modelling signal platoon patterns by approach lane use and movement class, and to compare the resulting traffic performance measures (delay, back of queue, level of service) with those estimated using the traditional method based on lane groups or links.
Abstract
This paper compares two analytical approaches for modelling signalised intersection networks in relation to the assessment of signal coordination quality as a fundamental [...]
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Evaluating Capacity and Delay for Signalized Arterials with Freight Deliveries
A. Keegan, E. Gonzales

Collection of Transportation Research Procedia (2017).

Abstract
Freight deliveries on signalized urban streets are known to cause lane blockages during delivery. Traffic congestion associated with urban freight deliveries has gained increasing attention recently as traffic engineers and planners are tasked with finding solutions to manage increasing demand more sustainably with limited road capacity. The goal of this research is to evaluate two models for quantifying the capacity and delay effects of a lane blocking freight delivery on a signalized urban street. The two methods are: an all-or-nothing model similar to methodology used in the Highway Capacity Manual 2010 (HCM2010) and a detailed analytical model consistent with kinematic wave theory. The purpose is to provide insight on the use of these tools for analysis of urban freight delivery policy. The results of the two models are compared with each. A simulation of 8th Avenue in New York has been calibrated to observed freight deliveries from a six-hour period, and the simulated results confirm effect of delivery location on capacity and delay. The results show that the methods from the HCM2010 to account for the effects of buses stopping for passengers provide only a coarse representation of the capacity and delay effects of urban freight deliveries. The more detailed approach that accounts for the dynamics of queuing provide closed form analytical formulas for delay and capacity that can account for varying locations of deliveries, long delivery durations, and different impacts on different lane groups.
Abstract
Freight deliveries on signalized urban streets are known to cause lane blockages during delivery. Traffic congestion associated with urban freight deliveries has gained increasing [...]
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Metallothionein’s role in PCB126 induced hepatotoxicity and hepatic micronutrient disruption
W. Klaren, S. Flor, K. Gibson-Corley, G. Ludewig, L. Robertson

Collection of Toxicology Reports (2017).

Abstract
Polychlorinated biphenyls (PCBs), industrial chemicals and persistent environmental pollutants, are found in rural and urban settings. Rodent studies have shown that exposure to PCB126, a dioxin-like PCB, causes a significant disruption of hepatic micronutrient homeostasis and an increase in metallothionein (MT), an antioxidant protein and metal carrier. A MT knockout mouse strain was used to assess metallothionein’s role in micronutrient disruption and overall hepatotoxicity. Twenty four 129S male mice (12 wild type (WT) and 12 MT knockout (MTKO)) were placed on a purified diet (AIN-93G) for 3 weeks to achieve hepatic metal equilibrium. Mice were then given a single IP injection of either vehicle or 150 μmol/kg PCB126 in vehicle. The animals were sacrificed 2 weeks later and organs processed for analysis. Liver histology, hepatic lipids, gene expression, micronutrient and ROS status were investigated. Liver weights, liver lipids, ROS, and hepatocyte vacuolation were increased with PCB126 exposure along with AhR responsive genes. The MTKO animals had more severe histological changes in the liver and elevated liver lipids than their wild type counterparts. Hepatic and renal metals levels (Cu, Zn, Se and Mn) were mostly reduced by PCB126 treatment. Renal micronutrients were more affected by PCB126 treatment in the MTKO animals. This research suggests that MT may not be the sole/primary cause of the metal disruption caused by PCB126 exposure in mice, but may provide protection against overall hepatotoxicity.
Abstract
Polychlorinated biphenyls (PCBs), industrial chemicals and persistent environmental pollutants, are found in rural and urban settings. Rodent studies have shown that exposure [...]
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Toxicological evaluation of a novel umami flavour compound: 2-(((3-(2,3-Dimethoxyphenyl)-1H -1,2,4-triazol-5-yl)thio)methyl)pyridine
D. Karanewsky, A. Arthur, H. Liu, B. Chi, L. Ida, S. Markison

Collection of Toxicology Reports (2017).

Abstract
A toxicological evaluation of a umami flavour compound, 2-(((3-(2, 3-dimethoxyphenyl)-1H -1, 2, 4-triazol-5-yl)thio)methyl)pyridine (S3643, CAS 902136-79-2), was completed for the purpose of assessing its safety for use in food and beverage applications. S3643 undergoes extensive oxidative metabolism in vitro with rat microsomes producing the S3643-sulfoxide and 4′-hydroxy-S3643 as the major metabolites. In incubations with human microsomes, the O -demethyl-S3643 and S3643-sulfoxide were produced as the major metabolites. In pharmacokinetic studies in rats, the S3643-sulfoxide represents the dominant biotransformation product. S3643 was not found to be mutagenic or clastogenic in vitro, and did not induce micronuclei in CHO-WBL cells. In subchronic oral toxicity studies in rats, the no-observed-adverse-effect-level (NOAEL) for S3643 was 100 mg/kg bw/day (highest dose tested) when administered in the diet for 90 consecutive days.
Abstract
A toxicological evaluation of a umami flavour compound, 2-(((3-(2, 3-dimethoxyphenyl)-1H -1, 2, 4-triazol-5-yl)thio)methyl)pyridine (S3643, CAS 902136-79-2), was completed [...]
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Concentrations and exposure risks of some metals in facial cosmetics in Nigeria
C. Iwegbue, F. Bassey, G. Obi, G. Tesi, B. Martincigh

Collection of Toxicology Reports (2017).

Abstract
The concentrations of nine metals (Cd, Pb, Ni, Cr, Co, Cu, Fe, Mn and Zn) were determined in lip sticks, lip glosses, lip balms, eye pencils, eyeliners, eye shadows, blushes, mascaras and face powders. The study was aimed at providing information on the risk associated with human exposure to metals in these facial cosmetic products. The concentrations of metals in the samples were measured by atomic absorption spectrometry after digestion with a mixture of nitric acid, hydrochloric acid and hydrogen peroxide. The mean concentrations of metals in these facial cosmetics ranged from 3.1 to 8.4 μg g−1 Cd, 12–240 μg g−1 Pb, 9.1–44 μg g−1 Cr, 18–288 μg g−1 Ni, 1.6–80 μg g−1 Cu, 7.9–17 μg g−1 Co, 2.3–28 mg g−1 Fe, 12–230 μg g−1 Mn, and from 18 to 320 μg g−1 Zn. The concentrations of Ni, Cr and Co were above the suggested safe limit of 1 μg g−1 for skin protection, while Cd and Pb were above the Canadian specified limits. The systemic exposure dosage (SED) values for these metals obtained from the use of these facial cosmetic products were below their respective provisional tolerable daily intake (PTDI)/or recommended daily intake (RDI) values. The margin of safety values obtained were greater than 100 which indicated that the concentrations of the metals investigated in these facial cosmetics do not present considerable risk to the users except in the case of face powders.
Abstract
The concentrations of nine metals (Cd, Pb, Ni, Cr, Co, Cu, Fe, Mn and Zn) were determined in lip sticks, lip glosses, lip balms, eye pencils, eyeliners, eye shadows, blushes, [...]
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Downregulation of nicotinic and muscarinic receptor function in rats after subchronic exposure to diazinon
S. Ivanović, B. Dimitrijević, V. Ćupić, M. Jezdimirović, S. Borozan, M. Savić, D. Savić

Collection of Toxicology Reports (2017).

Abstract
Diazinon (DZN) is an organophosphate insecticide which exerts its effect through the inhibition of acetylcholinesterase enzyme (AChE). In this work, we studied the development of tolerance to subchronic p.o. administration of DZN in rats, under both in vivo and in vitro conditions. A group of 20 rats (2 groups, n = 10) was administered p.o. the 1/10 of established LD50 DZN (namely 55.87 mg/kg bw) for 28 days. On the 14th and 28th day of study with isolated diaphragm and ileum, we examined the downregulation of nicotinic and muscarinic receptor function through Electrical Field Stimulation (EFS). Maximum contractility of the diaphragm was recorded on the 14th day of the study (25% higher compared to the non-treated rats), while on the 28th day the contractions almost did not differ from the values found in non-treated rats. EFS of isolated ileum on the 14th day of study caused significantly higher contractions compared to the non-treated rats, but after 28 days, ileum contractions decreased approximately to the level of contractions in non-treated rats. On the 14th study day, we also recorded increased amplitude of spontaneous ileum contractions, compared to non-treated rats. The application of increasing ACh concentrations caused dose-dependent ileum contractions, without statistically significant differences of median effective concentration (EC50 ) values in non-treated and treated rats. Tolerance to subchronic DZN administration develops due to various adaptation mechanisms, including the most important one—downregulation of nicotinic and muscarinic receptor function.
Abstract
Diazinon (DZN) is an organophosphate insecticide which exerts its effect through the inhibition of acetylcholinesterase enzyme (AChE). In this work, we studied the development [...]
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Does amikacin treatment cause subclinical hearing loss in patients with cystic fibrosis?
F. Solmaz, E. Gündoğdu, D. Akduman, M. Haksever, O. Dikici, F. Ünal

Collection of Toxicology Reports (2017).

Abstract
Aminoglycosides (AGs) have been widely used for potential life-threatening bacterial infections. Although AGs are well known for their ototoxic side effects, some AGs such as amikacin are considered less harmful to auditory functions, thus, auditory monitoring is mostly neglected during treatment with these drugs. To reflect the potential auditory hazards of repeated amikacin use on the patients with cystic fibrosis (CF). 32CF patients with prior exposure to at least 3 courses of amikacin (the CF group) and 35 non-CF patients visiting the outpatient clinic with any complaint other than hearing loss and no history of treatment with any AG(the control, or C group) were compared with pure-tone audiometry(PTA). The diagnosis of CF was made by Nanoduck sweat test. The average age of the participants were 8.25 ± 2.76 years in the CF group and 8.58 ± 2.00 years in the C group (ranging from 5 to 13 years). 29 (43.28%) of the cases were female and 38 (56.71%) were male. Clinical SNHL(sensorineural hearing loss) was detected in 4 of the 32 subjects in the CF group. None of the subjects in the C group exhibited clinical SNHL. There was no statistically significant difference between the groups with regard to presence or absence of clinical SNHL (p > 0.05). However, hearing levels of the CF group were around 20 dB(decibel) HL(hearing loss), whereas hearing levels of the C group were around 5 dB. This difference was statistically significant for the pure tone averages of both all frequencies and speech frequencies (p < 0.05). Repetitive exposure to AGs can cause permanent, although mild, sensorineural hearing loss. For prevention, hearing status of the patient should be closely monitored and treatment of choice should be precisely tailored according to the audiological evaluation. This is especially important in patients with CF who frequently experience medical conditions necessitating AGs use.
Abstract
Aminoglycosides (AGs) have been widely used for potential life-threatening bacterial infections. Although AGs are well known for their ototoxic side effects, some AGs such [...]
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Chemical and biological studies of β -carotene after exposure to Cannabis sativa smoke
D. Monte, J. Tenório, I. Bastos, F. Mendonça, J. Neto, T. Silva, C. Ramos

Collection of Toxicology Reports (2017).

Abstract
Considering the increase in consumption of Cannabis sativa and the use of the compound β- carotene (BC) as supplement, we investigated potential changes in the chemical and biological proprieties of BC after exposure to C. sativa smoke (CSS). Our results showed that the BC exposed to CSS underwent 98.8% degradation and suffered loss of its antiradical activity. The major degradation products identified were 3-hydroxy-2, 4, 4-trimethylpentyl)2-methylpropanoate and (2-ethyl-3-hydroxyhexyl)2-methylpropanoate compounds. These are found in higher levels in the exhalations of colorectal cancer patients and are similar to the toxic products associated with lipid peroxidation of polyunsaturated fatty acids. In toxicological assays using micro-crustacean Artemia salina the BC was non-toxic, while the BC degraded by CSS had a toxicity of LC50 = 397.35 μg/mL. In Wistar rats, females treated with BC degraded by CSS (BCCSS) showed whitish liver spots, alterations in liver weight and in bilirubin and alkaline phosphatase levels, and decrease in the number of leukocytes associated with atypical lymphocytosis. In male rats, there was an increase in the number of leukocytes when compared to the control group. In the histopathological analysis, the cortical region of the kidneys showed the presence of discrete amorphous eosinophilic material (cylinders) in the lumen of the proximate and distal convoluted tubules. In general, the BC in contact with CSS undergoes chemical changes and exhibits toxicity to rats and Artemia salina .
Abstract
Considering the increase in consumption of Cannabis sativa and the use of the compound β- carotene (BC) as supplement, we investigated potential changes in the chemical and [...]
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Use of Bidens pilosa L. (Asteraceae) and Curcuma longa L. (Zingiberaceae) to treat intestinal mucositis in mice: Toxico-pharmacological evaluations
C. Bastos, P. Ávila, E. Filho, R. Ávila, A. Batista, S. Fonseca, E. Lima, R. Marreto, E. Mendonça, M. Valadares

Collection of Toxicology Reports (2017).

Abstract
Several studies towards the development of an effective treatment for intestinal mucositis have been reported, since this condition represents a major problem in clinical oncology practice due to cytotoxic effects of chemotherapy. However standardized protocols and universally accepted treatment options are yet to be established. Given above, this study evaluated the protective effects of a mucoadhesive formulation containing both Bidens pilosa L. (Asteraceae) (BP) and curcuminoids from Curcuma longa L. (Zingiberaceae) (CL) on intestinal mucositis induced by 5-fluoruoacil (5-FU) in mice. As expected, animals only treated with 5-FU (200 mg/kg) showed a significant reduction of 60.3 and 42.4% in villi and crypts size, respectively, when compared to control. On the other hand, the proposed therapeutic/prophylactic treatment with mucoadhesive formulations managed to reduce histopathologic changes in mice bearing mucositis, especially at 125 mg/kg BP + 15 mg/kg CL dose. The formulation promoted an increase of 275.5% and 148.7% for villi and crypts size, respectively. Moreover, chemotherapy-related weight loss was reduced by 7.4% following the treatment. In addition, an increase of 10 and 30.5% in red and white blood cells was observed when compared to 5-FU group. Furthermore, treatments with the mucoadhesive formulation containing BP/CL up modulated Ki-67 and Bcl-2 expression while reduced pro-apoptotic regulator Bax. The formulation also modulated inflammatory response triggered by 5-FU through reduction of 68% of myeloperoxidase activity and a 4-fold increase in anti-inflammatory IL-10 levels. In parallel, the oxidative stress via lipid peroxidation was reduced as indicated by decrease of 63% of malondialdehyde concentrations. Additionally, the new formulation presented low acute oral systemic toxicity, being classified in the category 5 (2000 mg/kg < LD50 < 5000 mg/kg) of the Globally Harmonized Classification System. This study showed an interesting potential of the mucoadhesive formulation of BP/CL for the treatment of 5-FU-induced intestinal mucositis. Given the perspectives for the development of a new medicine, clinical studies are in progress to better understand the protective effects of this innovative formulation in treating mucositis.
Abstract
Several studies towards the development of an effective treatment for intestinal mucositis have been reported, since this condition represents a major problem in clinical [...]
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Transcriptomics analysis and hormonal changes of male and female neonatal rats treated chronically with a low dose of acrylamide in their drinking water
R. Collí-Dulá, M. Friedman, B. Hansen, N. Denslow

Collection of Toxicology Reports (2017).

Abstract
Acrylamide is known to produce follicular cell tumors of the thyroid in rats. RccHan Wistar rats were exposed in utero to a carcinogenic dose of acrylamide (3 mg/Kg bw/day) from gestation day 6 to delivery and then through their drinking water to postnatal day 35. In order to identify potential mechanisms of carcinogenesis in the thyroid glands, we used a transcriptomics approach. Thyroid glands were collected from male pups at 10 PM and female pups at 10 AM or 10 PM in order to establish whether active exposure to acrylamide influenced gene expression patterns or pathways that could be related to carcinogenesis. While all animals exposed to acrylamide showed changes in expected target pathways related to carcinogenesis such as DNA repair, DNA replication, chromosome segregation, among others, animals that were sacrificed while actively drinking acrylamide-laced water during their active period at night showed increased changes in pathways related to oxidative stress, detoxification pathways, metabolism, and activation of checkpoint pathways, among others. In addition, thyroid hormones, triiodothyronine (T3) and thyroxine (T4), were increased in acrylamide-treated rats sampled at night, but not in quiescent animals when compared to controls. The data clearly indicate that time of day for sample collection is critical to identifying molecular pathways that are altered by the exposures. These results suggest that carcinogenesis in the thyroids of acrylamide treated rats may ensue from several different mechanisms such as hormonal changes and oxidative stress and not only from direct genotoxicity, as has been assumed to date.
Abstract
Acrylamide is known to produce follicular cell tumors of the thyroid in rats. RccHan Wistar rats were exposed in utero to a carcinogenic dose of acrylamide (3 mg/Kg bw/day) [...]
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Specific long non-coding RNAs response to occupational PAHs exposure in coke oven workers
C. Gao, Z. He, J. Li, X. Li, Q. Bai, Z. Zhang, X. Zhang, S. Wang, X. Xiao, F. Wang, . Yan, D. Li, L. Chen, X. Zeng, Y. Xiao, G. Dong, Y. Zheng, Q. Wang, W. Chen

Collection of Toxicology Reports (2017).

Abstract
To explore whether the alteration of lncRNA expression is correlated with polycyclic aromatic hydrocarbons (PAHs) exposure and DNA damage, we examined PAHs external and internal exposure, DNA damage and lncRNAs (HOTAIR, MALAT1, TUG1 and GAS5) expression in peripheral blood lymphocytes (PBLCs) of 150 male coke oven workers and 60 non-PAHs exposure workers. We found the expression of HOTAIR, MALAT1, and TUG1 were enhanced in PBLCs of coke oven workers and positively correlated with the levels of external PAHs exposure (adjusted Ptrend < 0.001 for HOTAIR and MALAT1, adjusted Ptrend = 0.006 for TUG1). However, only HOTAIR and MALAT1 were significantly associated with the level of internal PAHs exposure (urinary 1-hydroxypyrene) with adjusted β = 0.298, P = 0.024 for HOTAIR and β = 0.090, P = 0.034 for MALAT1. In addition, the degree of DNA damage was positively associated with MALAT1 and HOTAIR expression in PBLCs of all subjects (adjusted β = 0.024, P = 0.002 for HOTAIR and β = 0.007, P = 0.003 for MALAT1). Moreover, we revealed that the global histone 3 lysine 27 trimethylation (H3K27me3) modification was positively associated with the degree of genetic damage (β = 0.061, P < 0.001) and the increase of HOTAIR expression (β = 0.385, P = 0.018). Taken together, our findings suggest that altered HOTAIR and MALAT1 expression might be involved in response to PAHs-induced DNA damage.
Abstract
To explore whether the alteration of lncRNA expression is correlated with polycyclic aromatic hydrocarbons (PAHs) exposure and DNA damage, we examined PAHs external and internal [...]
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Repeated dose studies with pure Epigallocatechin-3-gallate demonstrated dose and route dependant hepatotoxicity with associated dyslipidemia
B. Ramachandran, S. Jayavelu, K. Murhekar, T. Rajkumar

Collection of Toxicology Reports (2017).

Abstract
EGCG (Epigallocatechin-3-gallate) is the major active principle catechin found in green tea. Skepticism regarding the safety of consuming EGCG is gaining attention, despite the fact that it is widely being touted for its potential health benefits, including anti-cancer properties. The lack of scientific data on safe dose levels of pure EGCG is of concern, while EGCG has been commonly studied as a component of GTE (Green tea extract) and not as a single active constituent. This study has been carried out to estimate the maximum tolerated non-toxic dose of pure EGCG and to identify the treatment related risk factors. In a fourteen day consecutive treatment, two different administration modalities were compared, offering an improved [i.p (intraperitoneal)] and limited [p.o (oral)] bioavailability. A trend of dose and route dependant hepatotoxicity was observed particularly with i.p treatment and EGCG increased serum lipid profile in parallel to hepatotoxicity. Fourteen day tolerable dose of EGCG was established as 21.1 mg/kg for i.p and 67.8 mg/kg for p.o. We also observed that, EGCG induced effects by both treatment routes are reversible, subsequent to an observation period for further fourteen days after cessation of treatment. It was demonstrated that the severity of EGCG induced toxicity appears to be a function of dose, route of administration and period of treatment.
Abstract
EGCG (Epigallocatechin-3-gallate) is the major active principle catechin found in green tea. Skepticism regarding the safety of consuming EGCG is gaining attention, despite [...]
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Arsenic inhibits stem cell differentiation by altering the interplay between the Wnt3a and Notch signaling pathways
L. Bain, J. Liu, R. League

Collection of Toxicology Reports (2017).

Abstract
Millions of people are exposed to arsenic through their drinking water and food, but the mechanisms by which it impacts embryonic development are not well understood. Arsenic exposure during embryogenesis is associated with neurodevelopmental effects, reduced weight gain, and altered locomotor activity, and in vitro data indicates that arsenic exposure inhibits stem cell differentiation. This study investigated whether arsenic disrupted the Wnt3a signaling pathway, critical in the formation of myotubes and neurons, during the differentiation in P19 mouse embryonic stem cells. Cells were exposed to 0, 0.1, or 0.5 μM arsenite, with or without exogenous Wnt3a, for up to 9 days of differentiation. Arsenic exposure alone inhibits the differentiation of stem cells into neurons and skeletal myotubes, and reduces the expression of both β-catenin and GSK3β mRNA to ∼55% of control levels. Co-culture of the arsenic-exposed cells with exogenous Wnt3a rescues the morphological phenotype, but does not alter transcript, protein, or phosphorylation status of GSK3β or β-catenin. However, arsenic exposure maintains high levels of Hes5 and decreases the expression of MASH1 by 2.2-fold, which are anti- and pro-myogenic and neurogenic genes, respectively, in the Notch signaling pathway. While rescue with exogenous Wnt3a reduced Hes5 levels, MASH1 levels stay repressed. Thus, while Wnt3a can partially rescue the inhibition of differentiation from arsenic, it does so by also modulating Notch target genes rather than only working through the canonical Wnt signaling pathway. These results indicate that arsenic alters the interplay between multiple signaling pathways, leading to reduced stem cell differentiation.
Abstract
Millions of people are exposed to arsenic through their drinking water and food, but the mechanisms by which it impacts embryonic development are not well understood. Arsenic [...]
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Interaction of p -benzoquinone with hemoglobin in smoker’s blood causes alteration of structure and loss of oxygen binding capacity
A. Ghosh, S. Banerjee, A. Mitra, M. Muralidharan, B. Roy, R. Banerjee, A. Mandal, I. Chatterjee

Collection of Toxicology Reports (2017).

Abstract
Cigarette smoke (CS) is an important source of morbidity and early mortality worldwide. Besides causing various life-threatening diseases, CS is also known to cause hypoxia. Chronic hypoxia would induce early aging and premature death. Continuation of smoking during pregnancy is a known risk for the unborn child. Although carbon monoxide (CO) is considered to be a cause of hypoxia, the effect of other component(s) of CS on hypoxia is not known. Here we show by immunoblots and mass spectra analyses that in smoker’s blood p -benzoquinone (p -BQ) derived from CS forms covalent adducts with cysteine 93 residues in both the β chains of hemoglobin (Hb) producing Hb-p -BQ adducts. UV–vis spectra and CD spectra analyses show that upon complexation with p -BQ the structure of Hb is altered. Compared to nonsmoker’s Hb, the content of α-helix decreased significantly in smoker’s Hb (p = 0.0224). p -BQ also induces aggregation of smoker’s Hb as demonstrated by SDS-PAGE, dynamic light scattering and atomic force microscopy. Alteration of Hb structure in smoker’s blood is accompanied by reduced oxygen binding capacity. Our results provide the first proof that p -BQ is a cause of hypoxia in smokers. We also show that although both p -BQ and CO are responsible for causing hypoxia in smokers, exposure to CO further affects the function over and above that produced by Hb-p -BQ adduct.
Abstract
Cigarette smoke (CS) is an important source of morbidity and early mortality worldwide. Besides causing various life-threatening diseases, CS is also known to cause hypoxia. [...]
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Acute toxicity of herbicide (glyphosate) in Clarias gariepinus juveniles
A. Sani, M. Idris

Collection of Toxicology Reports (2017).

Abstract
The constant discharge of agricultural waste into aquatic environment has led to accumulation of heavy chemicals and other variety of pollutants. Herbicides present in these wastes are washed down, carried by rains and flood to nearby aquatic environment. Glyphosate is one of the most popular herbicides used by farmers in Kano because of its active reaction on killing weeds without affecting the crops. A toxicity test of glyphosate was conducted using concentrations of 0, 0.004, 0.005, 0.006, 0.007 ml/l. The mortality rate of each concentration was determined and the physicochemical parameters (Dissolved oxygen and pH) were also determined. The result showed that high mortality occurs at 0.007 ml/l and less mortality was found at 0.004 ml/l. Hence, mortality is dose dependent. DO and pH decreases with increase in glyphosate concentration. Furthermore, the juveniles showed abnormal behaviour. The LC50 value at 96 h was 0.0072 ml/l. There was significant difference between the initial and final pH value (p < 0.05). On the other hand, the initial and final DO values showed no significant difference (p > 0.05). However, correlation between DO and pH showed no significant difference (p > 0.05). The findings of this study established that glyphosate has some level of toxicity on Clarias gariepinus juveniles. In addition, it was found that mortality, changes in behaviour, DO and pH are dose dependent. Therefore, it was suggested that an appropriate concentration that will not be detrimental to non-target organisms should be used by farmers. Alternatively, Biological method should be used as a substitute for chemical method of controlling weeds.
Abstract
The constant discharge of agricultural waste into aquatic environment has led to accumulation of heavy chemicals and other variety of pollutants. Herbicides present in these [...]
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Fish oil prevents excessive accumulation of subcutaneous fat caused by an adverse effect of pioglitazone treatment and positively changes adipocytes in KK mice
Y. Iizuka, H. Kim, M. Nakasatomi, T. Izawa, S. Hirako, A. Matsumoto

Collection of Toxicology Reports (2017).

Abstract
Pioglitazone, a thiazolidinedione (TZD), is widely used as an insulin sensitizer in the treatment of type 2 diabetes. However, body weight gain is frequently observed in TZD-treated patients. Fish oil improves lipid metabolism dysfunction and obesity. In this study, we demonstrated suppression of body weight gain in response to pioglitazone administration by combination therapy of pioglitazone and fish oil in type 2 diabetic KK mice. Male KK mice were fed experimental diets for 8 weeks. In safflower oil (SO), safflower oil/low-dose pioglitazone (S/PL), and safflower oil/high-dose pioglitazone (S/PH) diets, 20% of calories were provided by safflower oil containing 0%, 0.006%, or 0.012% (wt/wt) pioglitazone, respectively. In fish oil (FO), fish oil/low-dose pioglitazone (F/PL), and fish oil/high-dose pioglitazone (F/PH) diets, 20% of calories were provided by a mixture of fish oil and safflower oil. Increased body weight and subcutaneous fat mass were observed in the S/PL and S/PH groups, however, diets containing fish oil were found to ameliorate these changes. Hepatic mRNA levels of lipogenic enzymes were significantly decreased in fish oil-fed groups. These findings demonstrate that the combination of pioglitazone and fish oil decreases subcutaneous fat accumulation, ameliorating pioglitazone-induced body weight gain, through fish oil-mediated inhibition of hepatic de novo lipogenesis.
Abstract
Pioglitazone, a thiazolidinedione (TZD), is widely used as an insulin sensitizer in the treatment of type 2 diabetes. However, body weight gain is frequently observed in TZD-treated [...]
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Inhibitory effect of Camellia sinensis , Ilex paraguariensis and Ardisia compressa tea extracts on the proliferation of human head and neck squamous carcinoma cells
M. Ramirez-Mares, H. Kobayashi, E. Mejia

Collection of Toxicology Reports (2017).

Abstract
In vitro cell proliferation, cell cycle arrest and induction of apoptosis were investigated, using three human head and neck squamous cell carcinoma (HNSCC) cell lines (OSCC-3, SCC-61, and SQ-20B). Aqueous extracts of Camellia sinensis, Ilex paraguariensis, and Ardisia compressa were tested and (−) epigallocatechin-3-gallate (EGCG) was used for comparison. For EGCG the IC50 values were between 80 and 166 μM and for the extracts among 75 and 505 μM eq. (+) catechin, with C. sinensis demonstrating dominant cytotoxicity. There was not a correlation between antioxidant capacity and cytotoxicity. Flow cytometry analysis revealed similarities in response for EGCG and C. sinensis . The A. compressa extract altered DNA distribution (P < 0.05) and was the most effective in induction of apoptosis via caspases (P < 0.05). Not all HNSCC cells tested responded to the same preventive agents. The fact that A. compressa inhibits HNSCC cell proliferation makes this aqueous extract a potential source of chemopreventive agents.
Abstract
In vitro cell proliferation, cell cycle arrest and induction of apoptosis were investigated, using three human head and neck squamous cell carcinoma (HNSCC) cell lines (OSCC-3, [...]
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Hepatoprotective effect of grape seed proanthocyanidins on Cadmium-induced hepatic injury in rats: Possible involvement of mitochondrial dysfunction, inflammation and apoptosis
S. Miltonprabu, . Nazimabashir, V. Manoharan

Collection of Toxicology Reports (2017).

Abstract
The present study was undertaken to evaluate the possible ameliorative role of grape seed proanthocyanidins (GSP) against Cadmium (Cd) induced hepatic inflammation, apoptosis and hepatic mitochondrial toxicity in rats. Male Wistar rats were distributed in four experimental groups: control, GSP, Cd and Cd + GSP. Exposure to a hepatotoxic dose of Cd (5 mg/kg BW) caused liver damage, coupled with enhanced reactive oxygen species (ROS) generation, increased inflammation and apoptosis in liver with increased DNA damage in hepatocytes of rats. Mitochondria were isolated from the hepatic tissues of rats from each group. Our results showed significant decrease in the tri-carboxylic acid cycle enzymes, increased mitochondrial swelling, inhibition of cytochrome c oxidase activity and complex I–III, II–III and IV mediated electron transfer, decreased mitochondrial ATPases, a reduction in calcium content and mitochondrial oxygen consumption in Cd treated rats. All these molecular changes caused by Cd were alleviated by the pre-supplementation with GSP (100 mg/kg BW). The ultra structural changes in the liver also support our findings. From our results, it is clearly indicated that the free radical scavenging, metal chelating and antioxidant potentials of GSP might be the possible reason, responsible for the rescue action against Cd induced mitochondrial damage in the liver of rats.
Abstract
The present study was undertaken to evaluate the possible ameliorative role of grape seed proanthocyanidins (GSP) against Cadmium (Cd) induced hepatic inflammation, apoptosis [...]
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Evaluation of the anti-inflammatory activities of Quillaja saponaria Mol. saponin extract in mice
S. Sarkhel

Collection of Toxicology Reports (2017).

Abstract
Quillaja saponaria bark contains a high percentage of triterpene saponins and has been used for centuries as antiinflammatory and analgesic agent in Chilean folk medicine. In the Present study the anti-inflammatory activities of the aqueous extract of commercially partially purified saponin from Quillaja saponari a Mol. in in vivo animal models. Aqueous extract of the plant material was prepared by cold maceration. The anti-inflammatory activity of a commercial Quillaja saponaria Mol. (QS) saponin extract was investigated by carragenan induced mice paw edema model for acute inflammation (Winter, 1962) [16] . The anti-inflammatory activity was evaluated by carragenan in paw edema model in swiss albino mice (18–20 g). The anti-inflammatory activity was found to be dose dependent in carragenan induced paw edema. QS was found to significantly (p < 0.05) reduce the carragenan induced mice paw edema (38.59%, 20 mg/kg bw) as compared to carragenan control. The percentage inhibition of standard anti-inflammatory drug indomethacin was (55%, 10 mg/kg, bw). The results of the present study demonstrate that the aqueous extract of Quillaja saponaria saponins (QS) possess significant anti-inflammatory activity.
Abstract
Quillaja saponaria bark contains a high percentage of triterpene saponins and has been used for centuries as antiinflammatory and analgesic agent in Chilean folk medicine. [...]
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Assessment of heavy metals contamination and human health risk in shrimp collected from different farms and rivers at Khulna-Satkhira region, Bangladesh
T. Sarkar, M. Alam, N. Parvin, Z. Fardous, A. Chowdhury, S. Hossain, M. Haque, N. Biswas

Collection of Toxicology Reports (2017).

Abstract
This study is aimed to assess the heavy metals contamination and health risk in Shrimp (Macrobrachium rosenbergii and Penaeus monodon ) collected from Khulna-Satkhira region in Bangladesh. The results showed that the Pb concentrations (0.52–1.16 mg/kg) in all shrimp samples of farms were higher than the recommended limit. The Cd levels (0.05–0.13 mg/kg) in all samples and Cr levels in all farms except tissue content at Satkhira farm were higher than the permissible limits. The individual concentration of Pb, Cd, and Cr between shrimp tissue and shell in all rivers and farms were not statistically significant (P > 0.05). Target hazard quotient (THQ) and hazard index (HI) were estimated to assess the non-carcinogenic health risks. Shrimp samples from all locations under the current study were found to be safe for consumption, the possibility of health risk associated with non-carcinogenic effect is very low for continuous consumption for 30 years.
Abstract
This study is aimed to assess the heavy metals contamination and health risk in Shrimp (Macrobrachium rosenbergii and Penaeus monodon ) collected from Khulna-Satkhira region [...]
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Curcuminoids from Curcuma longa L. reduced intestinal mucositis induced by 5-fluorouracil in mice: Bioadhesive, proliferative, anti-inflammatory and antioxidant effects
E. Filho, P. Ávila, C. Bastos, A. Batista, L. Naves, R. Marreto, E. Lima, E. Mendonça, M. Valadares

Collection of Toxicology Reports (2017).

Abstract
Intestinal mucositis is a frequent limiting factor in anticancer therapy and there is currently no broadly effective treatment targeted to cure this side effect. This study aimed to evaluate the effects of a mucoadhesive formulation containing curcuminoids (MFC) from Curcuma longa L. on the pathogenesis of 5-fluorouracil (5-FU)-induced intestinal mucositis. Three intraperitoneal 5-FU injections (200 mg/kg) were used to induce intestinal mucositis in adult Swiss male mice. Treatment was provided orally (MFC 3.75, 7.5 and 15 mg/kg), thirty minutes before 5-FU injections, daily until euthanasia. Duodenal samples were collected to perform morphometric and histopathological analysis, to investigate the expression of Ki-67, p53, Bax and Bcl-2 by immunohistochemistry, to evaluate neutrophil activity myeloperoxidase (MPO)-mediated and oxidative stress by malondialdehyde (MDA) determination. Mice body weight was assessed as well. As expected, 5-FU induced a significant weight loss (∼17%, P < 0.001), shortening in villi height (∼55.4%) and crypts depth (∼47%), and increased (∼64%) the histological severity score when compared to other groups (P < 0.05). These pathological changes were markedly alleviated by the three MFC treatment doses (P < 0.05), in special with the dose MFC 15 mg/kg. This dose also stimulated cell proliferation by ∼90% in the epithelial cells lining from villi and crypts (P < 0.05), reduced MPO levels and MDA formation by 60% and 44%, respectively (P < 0.05). Our data suggest the therapeutic potential of the formulation for treating intestinal mucositis in mice. Supplementary studies are underway searching for the elucidation of mechanisms involved in the protective effects of MFC in order to make this formulation a clinical tool for mucositis treatment.
Abstract
Intestinal mucositis is a frequent limiting factor in anticancer therapy and there is currently no broadly effective treatment targeted to cure this side effect. This study [...]
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Effect of Hecogenin on DNA instability
M. Cruz, S. Barroso, J. Navoni, M. Teles, J. Barbosa-Filho, H. Rocha, V. Amaral

Collection of Toxicology Reports (2017).

Abstract
Hecogenin is a sapogenin found in Agave species in high quantities and is responsible for the many therapeutic effects of these medicinal plants. In addition, this compound is also widely used in the pharmaceutical industry as a precursor for the synthesis of steroidal hormones and anti-inflammatory drugs. Despite Hecogenin being widely used, little is known about its toxicological properties. Therefore, the present study aimed to investigate the cytotoxic, genotoxic and mutagenic effects of Hecogenin on HepG2 cells. Cytotoxicity was analyzed using the MTT test. Then, genotoxic and mutagenic potentials were assessed by comet assay and cytokinesis-block micronucleus assay, respectively. Cytotoxic effect was observed only when cells were exposed to concentrations of Hecogenin equal or higher than 100 μM. Although a lower concentration of Hecogenin caused DNA damage, a reduction on nuclear mutagenic markers in HepG2 cells was observed. The results indicated that Hecogenin treatment generated DNA damage, but in fact it would be repaired, avoiding dissemination of the damage throughout the cell division. Further studies need to be performed to confirm the observed protective effect of Hecogenin against genomic instability.
Abstract
Hecogenin is a sapogenin found in Agave species in high quantities and is responsible for the many therapeutic effects of these medicinal plants. In addition, this compound [...]
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Exposure of the gilthead seabream (Sparus aurata ) to sediments contaminated with heavy metals down-regulates the gene expression of stress biomarkers
S. Benhamed, F. Guardiola, S. Martínez, M. Martínez-Sánchez, C. Pérez-Sirvent, M. Mars, M. Esteban

Collection of Toxicology Reports (2017).

Abstract
Heavy metals incidence in the aquatic environment and its accumulation in fish are under constant review. Gilthead seabream (Sparus aurata ) specimens were exposed for two weeks to sediments highly concentrated in metals, collected at the Portman Bay (Murcia, Spain). The metals bioaccumulation was tested in liver, muscle and skin. The potential of the sediment exposure to induce variation of the stress biomarkers genes was conducted in liver and skin. Results revealed that sediments were highly contaminated with metals. However, following 2 weeks exposure to the sediments, Cd accumulates only in liver. Interestingly, the expression of the genes mta, hsp 70 and hsp 90 were significantly down-regulated in skin. Nevertheless, cyp1a1 gene was up-regulated only in liver. Results uphold that the stress response magnitude was organ-dependent and the skin was the most responsive tissue to metal stress conditions. These results suggest that skin should be considered as target organ for biomarkers analysis in fishes.
Abstract
Heavy metals incidence in the aquatic environment and its accumulation in fish are under constant review. Gilthead seabream (Sparus aurata ) specimens were exposed for two [...]
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Evaluation of biological effects of intermediate frequency magnetic field on differentiation of embryonic stem cell
S. Yoshie, Y. Ogasawara, M. Ikehata, K. Ishii, Y. Suzuki, K. Wada, K. Wake, S. Nakasono, M. Taki, C. Ohkubo

Collection of Toxicology Reports (2017).

Abstract
The embryotoxic effect of intermediate frequency (IF) magnetic field (MF) was evaluated using murine embryonic stem (ES) cells and fibroblast cells based on the embryonic stem cell test (EST). The cells were exposed to 21 kHz IF–MF up to magnetic flux density of 3.9 mT during the cell proliferation process (7 days) or the cell differentiation process (10 days) during which an embryonic body differentiated into myocardial cells. As a result, there was no significant difference in the cell proliferation between sham- and IF–MF-exposed cells for both ES and fibroblast cells. Similarly, the ratio of the number of ES-derived cell aggregates differentiated to myocardial cells to total number of cell aggregates was not changed by IF–MF exposure. In addition, the expressions of a cardiomyocytes-specific gene, Myl2, and an early developmental gene, Hba-x, in the exposed cell aggregate were not altered. Since the magnetic flux density adopted in this study is much higher than that generated by an inverter of the electrical railway, an induction heating (IH) cooktop, etc . in our daily lives, these results suggested that IF–MF in which the public is exposed to in general living environment would not have embryotoxic effect.
Abstract
The embryotoxic effect of intermediate frequency (IF) magnetic field (MF) was evaluated using murine embryonic stem (ES) cells and fibroblast cells based on the embryonic [...]
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Evaluation of toxicity of biorational insecticides against larvae of the alfalfa weevil
G. Reddy, F. Antwi, G. Shrestha, T. Kuriwada

Collection of Toxicology Reports (2017).

Abstract
The alfalfa weevil, Hypera postica (Coleoptera: Curculionidae), is a major pest of alfalfa Medicago sativa L. (Fabaceae). While H. postica usually causes the most damage before the first cutting, in summer of 2015 damaging levels of the pest persisted in Montana well after the first harvest of alfalfa. Although conventional insecticides can control H. postica, these chemicals have adverse effects on non-target organisms including pollinators and natural enemy insects. In this context, use of biorational insecticides would be the best alternative options, as they are known to pose less risk to non-target organisms. We therefore examined the six commercially available biorational insecticides against H. postica under laboratory condition: Mycotrol® ESO (Beauveria bassiana GHA), Aza-Direct® (Azadirachtin), Met52® EC (Metarhizium brunneum F52), Xpectro OD® (B. bassiana GHA + pyrethrins), Xpulse OD® (B. bassiana GHA + Azadirachtin) and Entrust WP® (spinosad 80%). Concentrations of 0.1, 0.5, 1.0, and 2.0 times the lowest labelled rates were tested for all products. However, in the case of Entrust WP, additional concentrations of 0.001 and 0.01 times the lowest label rate were also assessed. Mortality rates were determined at 1–9 days post treatment. Based on lethal concentrations and relative potencies, this study clearly showed that Entrust was the most effective, causing 100% mortality within 3 days after treatment among all the tested materials. With regard to other biorational, Xpectro was the second most effective insecticide followed by Xpulse, Aza-Direct, Met52, and Mycotrol. Our results strongly suggested that these biorational insecticides could potentially be applied for H. postica control.
Abstract
The alfalfa weevil, Hypera postica (Coleoptera: Curculionidae), is a major pest of alfalfa Medicago sativa L. (Fabaceae). While H. postica usually causes the most damage before [...]
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Antioxidant protection of gallic acid against toxicity induced by Pb in blood, liver and kidney of rats
P. Reckziegel, V. Dias, D. Benvegnú, N. Boufleur, R. Barcelos, H. Segat, C. Pase, C. Santos, É. Flores, M. Bürger

Collection of Toxicology Reports (2017).

Abstract
The effect of the antioxidant gallic acid (GA) on Pb toxicity in blood, liver and kidney was investigated in the present study. Rats Wistar received Pb nitrate (50 mg/Kg/day, i.p., 5 days) followed by GA (13.5 mg/Kg, p.o., 3 days) or a chelating agent (EDTA, 55 mg/Kg, i.p.). As result, Pb decreased body weight, hematocrit and blood δ-aminolevulinic acid dehydratase (ALA-D) activity. In addition, high Pb levels were observed in blood and tissues, together with increased (1) lipid peroxidation in erythrocytes, plasma and tissues, (2) protein oxidation in tissues and (3) plasma aspartate transaminase (AST) levels. These changes were accompanied by decreasing in antioxidant defenses, like superoxide dismutase (SOD) activity in tissues and catalase (CAT) activity and reduced glutathione (GSH) in liver. GA was able to reverse Pb-induced decrease in body weight and ALA-D activity, as well as Pb-induced oxidative damages and most antioxidant alterations, however it did not decrease Pb bioaccumulation herein as EDTA did. Furthermore, EDTA did not show antioxidant protection in Pb-treated animals as GA did. In conclusion, GA decreased Pb-induced oxidative damages not by decreasing Pb bioaccumulation, but by improving antioxidant defenses, thus GA may be promising in the treatment of Pb intoxications.
Abstract
The effect of the antioxidant gallic acid (GA) on Pb toxicity in blood, liver and kidney was investigated in the present study. Rats Wistar received Pb nitrate (50 mg/Kg/day, [...]
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Arsenic induced hematological and biochemical responses in nutritionally important catfish Clarias batrachus (L.)
R. Kumar, T. Banerjee

Collection of Toxicology Reports (2017).

Abstract
The impact of sublethal toxicity of sodium arsenite on hematological and certain biochemical parameters of the fresh water catfish Clarias batrachus has been analyzed following exposure of sublethal concentration (1 mg/L, 5% of LC50 value) of sodium arsenite for 10, 30, 45, and 60 days. Arsenic bioaccumulation in the blood tissue of the fish increased progressively with increased period of exposure. The values of total erythrocyte count (TECs), total leucocytes count (TLCs), hemoglobin concentration, and packed cell volume (PCV) 1.40 ± 0.03 × 106 /mm3, 174.83 ± 2.74 × 103 /mm3, 5.01 ± 0.26 g/100 ml, 25.00 ± 1.06 were observed respectively at the end of 60 days of exposure. The results of hematological indices were found to be 179.23 ± 8.81fl/cell for mean corpuscular volume (MCV), 35.92 ± 1.89 pg/cell for mean corpuscular hemoglobin (MCH) and 20.17 ± 1.12 g/dl for mean corpuscular hemoglobin concentration (MCHC). The present findings are clearly indicating severe fish anemia due to the arsenic salt exposure. The continued arsenic toxicity results in decreased serum protein concentration that might be a cause for the loss of weight as well as weakness in the fish.
Abstract
The impact of sublethal toxicity of sodium arsenite on hematological and certain biochemical parameters of the fresh water catfish Clarias batrachus has been analyzed following [...]
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Ceramide-1-phosphate protection of cochlear hair cells against cisplatin ototoxicity
Q. Le, K. Tabuchi, A. Hara

Collection of Toxicology Reports (2017).

Abstract
Ceramide-1-phosphate (C1P) is a phosphorylated form of ceramide. While ceramide is known to be an inducer of apoptosis of cochlear hair cells in cisplatin ototoxicity, little is known about the function of C1P in cochlear diseases. The present study was designed to examine whether C1P could protect cochlear hair cells against cisplatin ototoxicity. Explants of cochlear basal turns collected from C57BL/6J mice at postnatal days 3–5 were used in all experiments. Cochlear explants were exposed to 5 or 10 μM cisplatin for 48 h to assess the effects of C1P, NVP-231 (a ceramide kinase inhibitor), or ceramide. Western blotting of pAkt/Akt and pMAPK/MAPK was examined to check whether this pathway was modulated by C1P. C1P activated the Akt and MAPK pathway and significantly reduced cochlear cell death induced by cisplatin. Coadministration of cisplatin and ceramide significantly increased cochlear hair cell death. In addition, when treating cochlear hair cells with NVP-231 in the presence of cisplatin or ceramide, a remarkable increase in apoptosis of hair cells was observed. The present findings confirmed the protective effects of C1P in the cisplatin ototoxicity. The balance between ceramide and C1P may play a critical role in the determination of hair cell fate in cisplatin ototoxicity.
Abstract
Ceramide-1-phosphate (C1P) is a phosphorylated form of ceramide. While ceramide is known to be an inducer of apoptosis of cochlear hair cells in cisplatin ototoxicity, little [...]
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Occupational exposure to pesticides and occurrence of the chromosomal translocation t(14;18) among farmers in Jordan
B. Qaqish, O. Al-Dalahmah, Y. Al-Motassem, A. Battah, S. Ismail

Collection of Toxicology Reports (2017).

Abstract
An increased incidence of non-Hodgkin’s lymphoma (NHL) has been reported in farmers and other occupational groups working with pesticides. In these individuals, an increased prevalence of the chromosomal translocation t(14, 18)(q32, q21), one of the most common chromosomal abnormalities in NHL, has been detected in peripheral blood lymphocytes. This translocation juxtaposes the antiapoptotic BCL2 protein to the immunoglobulin heavy chain gene locus (IGH) leading to overexpression of BCL2. This causes an increase in cell survival, paving the way for malignant transformation. The present study aimed to evaluate the association between the occurrence of the chromosomal translocation t(14, 18) and occupational exposure to pesticides among a group of Jordanian farmers. A total of 192 male subjects including 96 agricultural workers and 96 control subjects participated in this study. BCL2-IGH t(14, 18) fusions were detected by a nested polymerase chain reaction (PCR) assay targeting the major breakpoint region (MBR). We found that occupational exposure to pesticides in open-field farming and insecticide used on animals increased the frequency of the chromosomal translocation t(14, 18). Farmers occupationally exposed to pesticides and insecticide were 13.5 times more likely to harbor t(14, 18). 63.5% (61 of 96) of farmers compared to 11.5% (11 of 96) of controls carried the translocation (odds ratio: 13.5, 95% confidence interval (CI) = 6.3–28.6). We ruled out the influence of possible confounding factors such as age, duration of sun exposure, alcohol intake, smoking, and use of personal protective equipment. Our results indicate that pesticides increased the frequency of chromosomal translocation in the 14q32 region. Accordingly, the presented data agrees with previous suggestions from the literature that pesticides might be involved in the development of NHL through the t(14, 18) pathway.
Abstract
An increased incidence of non-Hodgkin’s lymphoma (NHL) has been reported in farmers and other occupational groups working with pesticides. In these individuals, an increased [...]
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Hepatic histomorphological and biochemical changes following highly active antiretroviral therapy in an experimental animal model: Does Hypoxis hemerocallidea exacerbate hepatic injury?
O. Azu, A. Jegede, O. Ugochukwu, I. Onanuga, S. Kharwa, E. Naidu

Collection of Toxicology Reports (2017).

Abstract
As the roll-out of antiretroviral therapy continues to drive downwards morbidity and mortality in people living with HIV/AIDS (PLWHAs), organ toxicities (especially the liver) are frequently becoming a major concern for researchers, scientists and healthcare planners. This study was conducted to investigate the possible protective effect of Hypoxis hemerocallidea (AP) against highly active antiretroviral therapy (HAART)-induced hepatotoxicity. A total of 63 pathogen-free adult male Sprague-Dawley rats were divided into 9 groups and treated according to protocols. While no mortality was reported, animals treated with adjuvant HAART and AP recorded least% body weight gain. Significant derangements in serum lipid profiles were exacerbated by treatment of with AP as LDL (increased p < 0.03), triglycerides (increased p < 0.03) with no change in total cholesterol levels. Adjuvant AP with HAART caused reduction in LDL (p < 0.05 and 0.03), increased HDL (p < 0.05) and TG (p < 0.05 and 0.001 for AP100 and AP200 doses respectively). Markers of liver injury assayed showed significant increase (p < 0.003, 0.001) in AST in AP alone as well as HAART+ vitamins C and E groups respectively. Adjuvant HAART and AP and vitamins C and E also caused significant declines in ALT and ALP levels. Serum GGT was not markedly altered. Disturbances in histopathology ranged from severe hepatocellular distortions, necrosis and massive fibrosis following co-treatment of HAART with vitamins C and E as well as HAART alone. These results warrant caution on the adjuvant use of AP with HAART by PLWHAs as implications for hepatocellular injuries are suspect with untoward cardiometabolic changes.
Abstract
As the roll-out of antiretroviral therapy continues to drive downwards morbidity and mortality in people living with HIV/AIDS (PLWHAs), organ toxicities (especially the liver) [...]
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Assessment of PAHs levels in some fish and seafood from different coastal waters in the Niger Delta
E. Nwaichi, S. Ntorgbo

Collection of Toxicology Reports (2017).

Abstract
Levels of sixteen polycyclic aromatic hydrocarbons (PAHs) in 30 edible tissues of selected frequently-consumed fish and seafood collected from three coastal waters of Niger Delta, namely, Sime, Kporghor and Iko were investigated in 2014. Gas chromatographic analysis were employed for PAHs determination. Observed mean PAHs levels in the samples ranged from below detection limit (BD) of analytical instrument to 22.400 ± 0.050 μg kg−1 wet wt. in Littorina littorea, BD to 87.400 ± 0.030 μg kg−1 wet wt. in Crassostrea virginica and from BD to 171.000 ± 0.430 μg kg−1 wet wt. in Periophthalmus koeleuteri. The highest average concentration of 171.000 ± 0.430 μg kg−1 wet wt. was recorded for Indeno [1, 2, 3-cd]pyrene from Sime water. High molecular weight PAHs (HMW-PAHs) were generally predominant compared to low molecular weight PAHs (LMW-PAHs). The LMW- PAH/HMW-PAH ratio was
Abstract
Levels of sixteen polycyclic aromatic hydrocarbons (PAHs) in 30 edible tissues of selected frequently-consumed fish and seafood collected from three coastal waters of Niger [...]
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Prevalence of aflatoxin and fumonisins (B1 + B2 ) in maize consumed in rural Malawi
D. Mwalwayo, B. Thole

Collection of Toxicology Reports (2017).

Abstract
A study was carried out to assess levels of contamination of aflatoxins and fumonisins (B1 + B2 ) in maize produced, stored and consumed in rural households in Malawi. A total of 9 districts were selected across the country representing 3 districts from each of the Northern, Central and Southern regions respectively. Households were selected at random in each district where 10 maize samples were collected for laboratory analysis. Aflatoxins and fumonisins were analyzed using a single step lateral flow immunochromatographic assay based on a competitive immunoassay format. The detection limit for aflatoxins was 2 μg/kg with a quantitation range of 2–150 μg/kg and that for fumonisins was 1 mg/kg with a quantitation range of 1–7 mg/kg. It was found that samples in the Southern region were highly contaminated, with the Chikhwawa district having high levels of both aflatoxins and fumonisins in maize. The Northern region had the least contamination. The maximum detected amount of aflatoxins was 140 μg/kg. The maximum detected amounts of fumonisins was 7 mg/kg. About 20% of maize samples exceeded the tolerable maximum limit for aflatoxins in Malawi. Aflatoxins and fumonisins were found to co-occur with contamination levels exceeding 100 μg/kg for both aflatoxins and fumonisins.
Abstract
A study was carried out to assess levels of contamination of aflatoxins and fumonisins (B1 + B2 ) in maize produced, stored and consumed in rural households in Malawi. A total [...]
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In vitro exposure of Adhatoda zeylanica to human renal cells lacks acute toxicity
M. Mossoba, T. Flynn, S. Vohra, P. Wiesenfeld, R. Sprando

Collection of Toxicology Reports (2017).

Abstract
Adhatoda zeylanica is a dietary supplement ingredient present in several types of dietary supplements, including weight loss, respiratory relief, and immune regulating products. Due to its reported wide range of uses in folk medicine, it was hypothesized that it may have the potential to target multiple organs and lead to a range of toxicity features. As a preliminary evaluation of the safety of this herbal ingredient, an investigation into its effects on the kidney was sought. An in vitro study of its potential nephrotoxicity using the HK-2 human proximal tubule cell line in a variety of functional indicators was performed to capture both general forms of cellular toxicity as well as ones that are specific to proximal tubules. A. zeylanica was only capable of inducing detrimental short-term toxicity to HK-2 cells at relatively high treatment concentrations when exposed directly to the cells. The lack of acute and potent toxicity of A. zeylanica under our experimental conditions calls for further studies to better define its toxicant threshold and establish safe dosage levels.
Abstract
Adhatoda zeylanica is a dietary supplement ingredient present in several types of dietary supplements, including weight loss, respiratory relief, and immune regulating products. [...]
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13-week dietary study and in vitro and in vivo genotoxicity studies of a structuring fat produced through a microalgal fermentation process
R. Matulka, T. Chan, R. Green, J. Carney, S. Franklin, P. Licari

Collection of Toxicology Reports (2017).

Abstract
Microalgae are increasingly being utilized as food ingredients for a variety of applications, including as sources of protein, egg and dairy substitutes, and cooking oils. The dietary safety of a new structuring fat produced using a heterotrophic fermentation process by a strain of Prototheca moriformis was evaluated in a 13-week dietary toxicity study and compared with kokum fat, a structuring fat of similar composition used in the food industry and derived from Garcinia indica seeds. The algal structuring fat was evaluated for its genotoxic potential using both in vitro and in vivo assays. No treatment-related adverse events occurred in rats consuming algal structuring fat or kokum fat in the 13-week study, no treatment-related effects were reported for body weight, food consumption, urinalysis, hematology, clinical chemistry, gross pathology, organ weights, or histopathology. While statistically significant effects occurred in some parameters, none were dose-related or considered adverse. Overall, the NOAELs for the algal structuring fat and the kokum fat were 100 000 ppm, the highest concentrations tested. The algal structuring fat was not mutagenic in the bacterial reverse mutation assay in the Salmonella typhimurium or Escherichia coli strains tested and was not clastogenic in the in vivo mouse bone marrow chromosome aberration assay.
Abstract
Microalgae are increasingly being utilized as food ingredients for a variety of applications, including as sources of protein, egg and dairy substitutes, and cooking oils. [...]
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Genetic and rat toxicity studies of cyclodextrin glucanotransferase
R. Maronpot, C. Hobbs, J. Davis, C. Swartz, M. Boyle, M. Koyanagi, S. Hayashi

Collection of Toxicology Reports (2017).

Abstract
Microbiologically derived cyclodextrin glucanotransferase (CGTase) is used commercially as a processing agent in manufacture of food, pharmaceuticals, and cosmetics. Its toxic potential was evaluated in anticipation of use in the production of alpha -glycosyl isoquercitrin, a water-soluble form of quercetin. Following OECD guidelines, CGTase, produced by Bacillus pseudalcaliphilus DK-1139, was evaluated in a genotoxicity battery consisting of a bacterial reverse mutation assay, an in vitro micronucleus (MN) assay and MN and comet assays using B6C3F1 male and female mice. These same genotoxicity assays were also conducted for sodium sulfate, a contaminant of CGTase preparation. In a 90-day Sprague Dawley rat toxicity study, CGTase was administered by gavage in water at daily doses of 0, 250, 500, and 1000 mg/kg/day. CGTase did not induce mutations with or without metabolic activation in the bacterial reverse mutation assay. Formation of micronuclei was not induced in either in vitro or in vivo MN assays with or without metabolic activation. No induction of DNA damage was detected in male or female mouse liver, stomach, or duodenum in the comet assay. Sodium sulfate also tested negative in these same genotoxicity assays. In the 90-day repeated dose rat study there were no treatment-related adverse clinical or pathological findings. The genotoxicity assays and repeated dose toxicity study support the safe use of CGTase in production of alpha -glycosyl isoquercitrin.
Abstract
Microbiologically derived cyclodextrin glucanotransferase (CGTase) is used commercially as a processing agent in manufacture of food, pharmaceuticals, and cosmetics. Its toxic [...]
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Safety assessment of a standardized polyphenolic extract of clove buds: Subchronic toxicity and mutagenicity studies
L. Vijayasteltar, G. Nair, B. Maliakel, R. Kuttan, K. I.M.

Collection of Toxicology Reports (2017).

Abstract
Despite the various reports on the toxicity of clove oil and its major component eugenol, systematic evaluations on the safety of polyphenolic extracts of clove buds have not been reported. Considering the health beneficial pharmacological effects and recent use of clove polyphenols as dietary supplements, the present study investigated the safety of a standardized polyphenolic extract of clove buds (Clovinol), as assessed by oral acute (5 g/kg b.wt. for 14 days) and subchronic (0.25, 0.5 and 1 g/kg b.wt. for 90 days) toxicity studies on Wistar rats and mutagenicity studies employing Salmonella typhimurium strains. Administration of Clovinol did not result in any toxicologically significant changes in clinical/behavioural observations, ophthalmic examinations, body weights, organ weights, feed consumption, urinalysis, hematology and clinical biochemistry parameters when compared to the untreated control group of animals, indicating the no observed-adverse-effect level (NOAEL) as 1000 mg/kg b.wt./day, the highest dose tested. Terminal necropsy did not reveal any treatment-related histopathology changes. Clovinol did not show genotoxicity when tested on TA-98, TA-100 and TA-102 with or without metabolic activation, rather exhibited significant antimutagenic potential against the known mutagens, sodium azide, NPD and tobacco as well as against 2-acetamidoflourene, which needed metabolic activation for mutagenicity.
Abstract
Despite the various reports on the toxicity of clove oil and its major component eugenol, systematic evaluations on the safety of polyphenolic extracts of clove buds have [...]
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Melatonin modulates drug-induced acute porphyria
S. Lelli, M. Mazzetti, L. Viale

Collection of Toxicology Reports (2017).

Abstract
This work investigated the modulation by melatonin (Mel) of the effects of the porphyrinogenic drugs 2-allyl-2-isopropylacetamide (AIA) and 3, 5-diethoxycarbonyl-1, 4-dihydro-2, 4, 6-collidine (DDC) on oxidative environment, glucose biosynthesis and heme pathway parameters. Administration of Mel before rat intoxication with AIA/DDC showed a clear beneficial effect in all cases. Mel induced decreases of 42% and 35% in the excretion of the hemeprecursors 5-aminolevulinic acid (ALA) and porphobilinogen (PBG), respectively, and a 33% decrease in the induction of the heme regulatory enzyme 5-aminolevulinic acid-synthase (ALA-S). The activity of the glucose metabolism enzyme phosphoenolpyruvate carboxykinase (PEPCK), which had been diminished by the porphyrinogenic treatment, was restored by 45% when animals were pre-treated with Mel. Mel abolished the modest decrease in glucose 6-phospatase (G6Pase) activity caused by AIA/DDC treatment. The oxidative status of lipids was attenuated by Mel treatment in homogenates by 47%, whereas no statistically significant AIA/DDC-induced increase in thiobarbituric acid reactive substances (TBARS) was observed in microsomes after Mel pre-treatment. We hypothesize that Mel may be scavenging reactive species of oxygen (ROS) that could be damaging lipids, PEPCK, G6Pase and ferrochelatase (FQ). Additionally, Mel administration resulted in the repression of the key enzyme ALA-S, and this could be due to an increase in glucose levels, which is known to inhibit ALA-S induction. The consequent decrease in levels of the heme precursors ALA and PBG had a beneficial effect on the drug-induced porphyria. The results obtained open the possibility of further research on the use of melatonin as a co-treatment option in acute porphyria.
Abstract
This work investigated the modulation by melatonin (Mel) of the effects of the porphyrinogenic drugs 2-allyl-2-isopropylacetamide (AIA) and 3, 5-diethoxycarbonyl-1, 4-dihydro-2, [...]
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Cyanotoxins at low doses induce apoptosis and inflammatory effects in murine brain cells: Potential implications for neurodegenerative diseases
L. Takser, N. Benachour, B. Husk, H. Cabana, D. Gris

Collection of Toxicology Reports (2017).

Abstract
Cyanotoxins have been shown to be highly toxic for mammalian cells, including brain cells. However, little is known about their effect on inflammatory pathways. This study investigated whether mammalian brain and immune cells can be a target of certain cyanotoxins, at doses approximating those in the guideline levels for drinking water, either alone or in mixtures. We examined the effects on cellular viability, apoptosis and inflammation signalling of several toxins on murine macrophage-like RAW264.7, microglial BV-2 and neuroblastoma N2a cell lines. We tested cylindrospermopsin (CYN), microcystin-LR (MC-LR), and anatoxin-a (ATX-a), individually as well as their mixture. In addition, we studied the neurotoxins β-N -methylamino-l -alanine (BMAA) and its isomer 2, 4-diaminobutyric acid (DAB), as well as the mixture of both. Cellular viability was determined by the MTT assay. Apoptosis induction was assessed by measuring the activation of caspases 3/7. Cell death and inflammation are the hallmarks of neurodegenerative diseases. Thus, our final step was to quantify the expression of a major proinflammatory cytokine TNF-α by ELISA. Our results show that CYN, MC-LR and ATX-a, but not BMAA and DAB, at low doses, especially when present in a mixture at threefold less concentrations than individual compounds are 3–15 times more potent at inducing apoptosis and inflammation. Our results suggest that common cyanotoxins at low doses have a potential to induce inflammation and apoptosis in immune and brain cells. Further research of the neuroinflammatory effects of these compounds in vivo is needed to improve safety limit levels for cyanotoxins in drinking water and food.
Abstract
Cyanotoxins have been shown to be highly toxic for mammalian cells, including brain cells. However, little is known about their effect on inflammatory pathways. This study [...]
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Food safety risk assessment for estimating dietary intake of sulfites in the Taiwanese population
K. Lien, D. Hsieh, H. Huang, C. Wu, S. Ni, M. Ling

Collection of Toxicology Reports (2017).

Abstract
The purpose of this study was to assess the health risk associated with dietary intake of sulfites for Taiwanese general consumers by conducting a total diet study (TDS). We evaluated the exposure of Taiwanese to sulfites in the diet and its associated health risk. This study used a list of 128 food items representing 83% of the total daily diet. Among the 128 food items, 59 items may contain sulfites. Samples of the 59 food items were collected and subjected to chemical analysis to determine the sulfur dioxide concentration. Health risk was assessed by calculating the ratio of exposure level to the acceptable daily intake (ADI) level of the analyte. For high-intake consumers, the HI of sulfites was 19.7% ADI for males over the age of three years at the 95th percentile, whereas for females over the age of 66, the HI was 17.8% ADI. The HI for high-intake consumers was above 10% ADI. This suggests that regulatory actions must be continued and that consumers should be advised to be aware of processed foods with relatively high contamination to avoid excessive exposure.
Abstract
The purpose of this study was to assess the health risk associated with dietary intake of sulfites for Taiwanese general consumers by conducting a total diet study (TDS). [...]
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Sequencing the exposome: A call to action
D. Jones

Collection of Toxicology Reports (2017).

Abstract
The exposome is a complement to the genome that includes non-genetic causes of disease. Multiple definitions are available, with salient points being global inclusion of exposures and behaviors, and cumulative integration of associated biologic responses. As such, the concept is both refreshingly simple and dauntingly complex. This article reviews high-resolution metabolomics (HRM) as an affordable approach to routinely analyze samples for a broad spectrum of environmental chemicals and biologic responses. HRM has been successfully used in multiple exposome research paradigms and is suitable to implement in a prototype universal exposure surveillance system. Development of such a structure for systematic monitoring of environmental exposures is an important step toward sequencing the exposome because it builds upon successes of exposure science, naturally connects external exposure to body burden and partitions the exposome into workable components. Practical results would be repositories of quantitative data on chemicals according to geography and biology. This would support new opportunities for environmental health analysis and predictive modeling. Complementary approaches to hasten development of exposome theory and associated biologic response networks could include experimental studies with model systems, analysis of archival samples from longitudinal studies with outcome data and study of relatively short-lived animals, such as household pets (dogs and cats) and non-human primates (common marmoset). International investment and cooperation to sequence the human exposome will advance scientific knowledge and also provide an important foundation to control adverse environmental exposures to sustain healthy living spaces and improve prediction and management of disease.
Abstract
The exposome is a complement to the genome that includes non-genetic causes of disease. Multiple definitions are available, with salient points being global inclusion of exposures [...]
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Sodium sulfite promotes the assembly and secretion of very low-density lipoprotein in HL-7702 hepatocytes
J. Bai, P. Lei, C. Zhao, Y. Wang, D. Yan, S. Yang

Collection of Toxicology Reports (2017).

Abstract
This study investigated the effects of Na2 SO3 on the fat metabolism in human normal diploid HL-7702 (referred as L-02) hepatocytes. After 24 h and 48 h, treatment with different concentrations of Na2 SO3, the intra and extra-hepatocellular triglyceride (TG) contents of L-02 were determined using chemical-enzymatic method. The contents of very low-density lipoprotein (VLDL) and apolipoprotein B100 (apoB100) in the culture supernatants were determined using enzyme-linked immunosorbent assay (ELISA). Western blot was applied to detect the expressions of fatty acid oxidation and fat synthesis related proteins, VLDL assembly and secretion in L-02 cells. Na2 SO3 treatment (10 mM, 24 h/48 h) significantly increased the intra TG level in the hepatocytes. Different concentrations of Na2 SO3 increased the extra-hepatocellular TG content. After 24 h exposure, the extracellular VLDL levels and secretions of apoB100 in 0.1–10 mM Na2 SO3 groups were significantly higher than that of the negative control (P < 0.05). Meanwhile, the expression of CPT1 and SREBP1 protein were significantly reduced by Na2 SO3 . MTP and TGH protein expressions were significantly elevated in each Na2 SO3 treatment group. The expression level of LDLR in hepatocytes was reduced by Na2 SO3 . Na2 SO3 exposure may promote the hepatocellular VLDL assembly and secretion, through increasing of MTP and TGH expressions and inhibiting the uptake of extracelluar VLDL.
Abstract
This study investigated the effects of Na2 SO3 on the fat metabolism in human normal diploid HL-7702 (referred as L-02) hepatocytes. After 24 h and 48 h, treatment with different [...]
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Cytotoxic effects of nickel nanowires in human fibroblasts
L. Felix, J. Perez, M. Contreras, T. Ravasi, J. Kosel

Collection of Toxicology Reports (2017).

Abstract
The increasing interest in the use of magnetic nanostructures for biomedical applications necessitates rigorous studies to be carried out in order to determine their potential toxicity. This work attempts to elucidate the cytotoxic effects of nickel nanowires (NWs) in human fibroblasts WI-38 by a colorimetric assay (MTT) under two different parameters: NW concentration and exposure time. This was complemented with TEM and confocal images to assess the NWs internalization and to identify any changes in the cell morphology. Ni NWs were fabricated by electrodeposition using porous alumina templates. Energy dispersive X-ray analysis, scanning electron microscopy and transmission electron microscopy imaging were used for NW characterization. The results showed decreased cell metabolic activity for incubation times longer than 24 h and no negative effects for exposure times shorter than that. The cytotoxicity effects for human fibroblasts were then compared with those reported for HCT 116 cells, and the findings point out that it is relevant to consider the cellular size. In addition, the present study compares the toxic effects of equivalent amounts of nickel in the form of its salt to those of NWs and shows that the NWs are more toxic than the salts. Internalized NWs were found in vesicles inside of the cells where their presence induced inflammation of the endoplasmic reticulum.
Abstract
The increasing interest in the use of magnetic nanostructures for biomedical applications necessitates rigorous studies to be carried out in order to determine their potential [...]
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Dose- and time-dependent changes in tissue levels of tetrabromobisphenol A (TBBPA) and its sulfate and glucuronide conjugates following repeated administration to female Wistar Han Rats
S. Borghoff, D. Wikoff, S. Harvey, L. Haws

Collection of Toxicology Reports (2017).

Abstract
Tetrabromobisphenol A (TBBPA), a nongenotoxic flame retardant, causes uterine tumors in female rats. A proposed mode of action (MoA) for these tumors involves an increase in the bioavailability of estradiol as a result of TBBPA inhibiting estrogen sulfotransferases (ES), the enzymes responsible for inactivating and enhancing the elimination of estradiol. The objective of this study was to evaluate the effect of dose and repeated administration of TBBPA on the level of TBBPA, TBBPA-glucuronide (GA) and TBBPA-sulfate (S) conjugates in plasma, liver and uterus of female Wistar Han rats administered TBBPA (50, 100, 250, 500 or 1000 mg/kg) for 28 consecutive days. In accordance with this objective, TBBPA sulfation was used as a surrogate for evaluating the potential for estradiol sulfation to be limited at high dose levels of TBBPA. Blood samples were collected at 4 and 8 h post-dosing on study day 7, 14, and 28, while liver and uterus were collected at the same time points following 28 days of dosing. Tissue samples were analyzed for TBBPA, TBBPA-GA and TBBPA-S by LC–MS/MS. A dose-related increase in the concentration of all three analytes occurred in plasma (day 7, 14, and 28) as well as liver and uterus tissue (day 28) at both 4 and 8 h post dose. The plasma concentration of TBBPA-GA and TBBPA-S was higher in animals dosed for 28 days compared to those dosed for 7 or 14 days showing an increase in systemic circulation of these conjugates with repeated administration. The balance of these conjugates was also different in tissues with TBBPA-S > TBBPA-GA at high doses in the liver and TBBPA-GA > TBBPA-S in both plasma and uterus. In all three tissues the ratio of TBBPA-S/TBBPA-GA showed a decreasing trend with dose, suggesting that at high TBBPA dose levels sulfation of TBBPA becomes limited. This effect was most apparent in the liver and plasma at 28 days of administration. Together these data show that administration of high doses of TBBPA associated with the induction of uterine tumors, results in a disruption in the balance of conjugates reflected by a decrease in the TBBPA-S/TBBPA-GA ratio. A limitation in the sulfation of TBBPA in vivo supports in vitro data defining TBBPA as an inhibitor of ES activity, thus providing further support that the proposed MoA occurs under conditions of high dose, chronic TBBPA administration to Wistar Han rats. Given that the uterine tumors observed in rats (250–1000 mg/kg-day) only occur at very high doses that perturb homeostatic control, it is unlikely such effects would occur in humans given that current TBBPA exposure levels are approximately eight orders of magnitude lower than these doses that are associated with exceeding the capacity of conjugation pathways in animal studies.
Abstract
Tetrabromobisphenol A (TBBPA), a nongenotoxic flame retardant, causes uterine tumors in female rats. A proposed mode of action (MoA) for these tumors involves an increase [...]
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The possible role of intravenous lipid emulsion in the treatment of chemical warfare agent poisoning
A. Eisenkraft, A. Falk

Collection of Toxicology Reports (2017).

Abstract
Organophosphates (OPs) are cholinesterase inhibitors that lead to a characteristic toxidrome of hypersecretion, miosis, dyspnea, respiratory insufficiency, convulsions and, without proper and early antidotal treatment, death. Most of these compounds are highly lipophilic. Sulfur mustard is a toxic lipophilic alkylating agent, exerting its damage through alkylation of cellular macromolecules (e.g., DNA, proteins) and intense activation of pro-inflammatory pathways. Currently approved antidotes against OPs include the peripheral anticholinergic drug atropine and an oxime that reactivates the inhibited cholinesterase. Benzodiazepines are used to stop organophosphate-induced seizures. Despite these approved drugs, efforts have been made to introduce other medical countermeasures in order to attenuate both the short-term and long-term clinical effects following exposure. Currently, there is no antidote against sulfur mustard poisoning. Intravenous lipid emulsions are used as a source of calories in parenteral nutrition. In recent years, efficacy of lipid emulsions has been shown in the treatment of poisoning by fat-soluble compounds in animal models as well as clinically in humans. In this review we discuss the usefulness of intravenous lipid emulsions as an adjunct to the in-hospital treatment of chemical warfare agent poisoning.
Abstract
Organophosphates (OPs) are cholinesterase inhibitors that lead to a characteristic toxidrome of hypersecretion, miosis, dyspnea, respiratory insufficiency, convulsions and, [...]
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Nrf2 activators as potential modulators of injury in human kidney cells
A. Atilano-Roque, X. Wen, L. Aleksunes, M. Joy

Collection of Toxicology Reports (2017).

Abstract
Cisplatin is a chemotherapeutic agent used in the treatment of solid tumors, with clinical use often complicated by kidney toxicity. Nuclear factor (erythroid-derived-2)-like 2 (Nrf2) is a transcription factor involved in kidney protectant effects. The purpose of this study was to determine whether the Nrf2 activators oltipraz, sulforaphane, and oleanolic acid could protect human kidney cells against cisplatin-induced injury and to compare the protective effects between three Nrf2 activators. Human proximal tubule cells (hPTC) and human embryonic kidney 293 cells (HEK293) were exposed to cisplatin doses in the absence and presence of Nrf2 activators. Pre- and delayed-cisplatin and Nrf2 activator exposures were also assessed. Cell viability was enhanced with Nrf2 activator exposures, with differences detected between pre- and delayed-treatments. Both sulforaphane and oltipraz increased the expression of anti-oxidant genes GCLC and NQO1. These findings suggest potential human kidney protective benefits of Nrf2 activators with planned exposures to cisplatin.
Abstract
Cisplatin is a chemotherapeutic agent used in the treatment of solid tumors, with clinical use often complicated by kidney toxicity. Nuclear factor (erythroid-derived-2)-like [...]
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Vanillin abrogates ethanol induced gastric injury in rats via modulation of gastric secretion, oxidative stress and inflammation
A. Asmari, H. Shahrani, N. Masri, A. Faraidi, I. Elfaki, M. Arshaduddin

Collection of Toxicology Reports (2017).

Abstract
Vanillin is commonly used as an additive in food, medicine and cosmetics, but its effect has not yet been studied in gastric injury. Therefore the effect of vanillin was studied in experimental gastric ulcer. Gastric secretion and acidity were studied in pylorus ligated rats. Ulcer index, levels of gastric mucus, malondialdehyde (MDA), myeloperoxidase activity (MPO), expression of nuclear factor kappa B (NF-κB) p65, and histopathological changes were determined in ethanol induced gastric ulcer. Pre treatment with vanillin significantly reduced gastric secretion (P < 0.001) and acidity (P < 0.0001) and gastric ulcer index scores (P < 0.001). and augmented the gastric mucosal defense. Vanillin significantly restored the depleted gastric wall mucus levels (P < 0.0001) induced by ethanol and also significantly attenuated ethanol induced inflammation and oxidative stress by the suppression of gastric MPO activity (P < 0.001), reducing the expression of NF-κB p65 and the increased MDA levels (P < 0.001). Vanillin was also effective in alleviating the damage to the histological architecture and the activation of mast cells induced by ethanol. Together the results of this study highlight the gastroprotective activity of vanillin in gastric ulcers of rats through multiple actions that include inhibition of gastric secretion and acidity, reduction of inflammation and oxidative stress, suppression of expression of NF-κB, and restoration of the histological architecture.
Abstract
Vanillin is commonly used as an additive in food, medicine and cosmetics, but its effect has not yet been studied in gastric injury. Therefore the effect of vanillin was studied [...]
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Visibilidad y enunciabilidad en la larga duración de la violencia política: La sombra azul de Sergio Schmucler 1
G. Villanueva

Acta Poética (2017).

Abstract
Una historia de vida, eje fundamental de un film, es la discursividad que hemos indagado para percibir sentidos nuevos en la relación cine, memoria y violencia en la zona amplia de los discursos producidos sobre el terrorismo de estado en Argentina. La sombra azul, con guión y dirección de Sergio Schmucler, irrumpe para desbaratar conciencias. Nuestro trabajo, filiado en el Análisis del Discurso, se ha detenido en la indagación de tres dispositivos: las visibilidades, las enunciabilidades y las temporalidades, superpuestas, fragmentarias a veces, otras omnipresentes, deslizadas en la larga duración de una memoria social. Estos dispositivos, elaborados por Foucault para blandir discursividades exasperantes de órdenes impuestos, constituyen un camino privilegiado para llegar, a través de su desgranamiento, a una verdad intolerable forjada en este film. En La sombra azul la larga duración de la violencia de estado, la impunidad de los represores durante la democracia y, fundamentalmente, un sobreviviente —a la tortura, la prisión, el exilio, perteneciente a la fuerza policial de una de las provincias más castigadas por la dictadura— son cincelados, en la heteroglosia, en el diálogo y en el antagonismo, con otras voces. Este sobreviviente, devenido en re-viviente señala cómo un marco ético, capaz de valorar la tragedia humana, lo erige en un don para dotar de verdad, para esclarecer a una sociedad que, en muchos espacios, aún permanece en sombra. Este recorrido discursivo señala cómo, desde la indecibilidad original de un sujeto doliente, irrumpen visibilidades y enunciabilidades capaces de decir verdad y así proseguir con una memoria que nunca cesa.
Abstract
Una historia de vida, eje fundamental de un film, es la discursividad que hemos indagado para percibir sentidos nuevos en la relación cine, memoria y violencia en la zona [...]
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El delirio frente a la razón en el Quijote
J. Vadillo

Acta Poética (2017).

Abstract
El artículo gira en torno a la tensión contrapuntística que crea el delirio frente a la razón en el Quijote. Partimos de la idea (que compartimos con María Zambrano) de que el delirio es una forma de inteligencia diferente a la inteligencia racional, y que es también una de las diferentes perspectivas (de acuerdo con Leo Spitzer) que conforman el mundo. Es el espacio de la metáfora, de la invención, de la alucinación, es el mundo de don Quijote. Nuestro caballero andante intentará verter su mundo sobre la realidad racional y allí se generará el enfrentamiento entre el delirio y la razón, en términos contrapuntísticos, la disonancia que se resuelve en consonancia casi siempre cuando es derrotado el delirio, en ese momento se acaba el tiempo sin tiempo de la aventura, y don Quijote vuelve al tiempo cronológico y distingue la realidad racional, pero no podrá aceptarla, a menos que esté encantada. Este tema es analizado a la luz de diversas obras, entre ellas: La ambigüedad en el Quijote de Manuel Durán, “Don Quijote” de Foucault, Meditaciones del Quijote, de Ortega y Gasset, “Ambigüedad de la novela”, de Octavio Paz, “Perspectivismo lingüístico en El Quijote”, de Leo Spitzer, etc.
Abstract
El artículo gira en torno a la tensión contrapuntística que crea el delirio frente a la razón en el Quijote. Partimos de la idea (que compartimos con María Zambrano) [...]
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Polisistemas anárquicos. La traducción política en el marco del polisistema
G. Torem

Acta Poética (2017).

Abstract
En este texto se reflexiona sobre la capacidad de la teoría del polisistema para analizar la traducción de textos políticos. Partiendo de las definiciones de cultura y centralidad esbozadas por Even Zohar, se concluye que existe una exclusión de lo político del objeto de estudio. La hipótesis es que, al incluir en su modelo a un sujeto traductor actuante en las luchas materiales del sistema político-cultural, el polisistema, como teoría, cobra nuevo valor y aplicabilidad. En este nuevo contexto, el traductor actúa sobre el sistema receptor como tal, pero también como intelectual y militante. Una derivación obvia es que la traducción deja de pensarse como mera actividad accesoria y pasa a conformar una red de relaciones en la que traductor, militante e intelectual son facetas de un mismo sujeto, aquí definido como internacional. Se toma como ejemplo de sistema político y cultural el anarquismo de principios de siglo xx y se destaca la figura de Diego Abad de Santillán, quien, desde su actividad como dirigente, periodista, escritor y traductor, canaliza a través de su persona las relaciones entre diversos subsistemas de una especie de macrosistema internacional de los movimientos anarquistas.
Abstract
En este texto se reflexiona sobre la capacidad de la teoría del polisistema para analizar la traducción de textos políticos. Partiendo de las definiciones de cultura y [...]
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L’archi -road movie, ou le routage des sens
P. Szendy

Acta Poética (2017).

Abstract
Cada film abre un mundo (o un cinemundo, como dice Jean-Luc Nancy). Por esto, el camino, y el road-movie como género, son más que meros tropos, más que simples metáforas para la película: son los sensorimotor schemata del cine pavimentando su propio camino. El problema de la sincronización por lo tanto se reformula como routing de los sentidos, cada vez en un sentido singular, como su colisión, donde sus trayectorias se cruzan. El artículo analiza el curso filmado por los ojos y oídos de un número de films como Blow Out (Brian De Palma, 1981), Lost Highway (David Lynch, 1997), and Deathproof (Quentin Tarantino, 2007).
Abstract
Cada film abre un mundo (o un cinemundo, como dice Jean-Luc Nancy). Por esto, el camino, y el road-movie como género, son más que meros tropos, más que simples metáforas [...]
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