bluuebunny/crossref_metadata_2025 huggingface dataset:
The comparison of gamma-radiation and electrical stress influences on oxide and interface defects in power VDMOSFET
Authors: Djoric-Veljkovic Snezana , Manic Ivica , Davidovic Vojkan , Dankovic Danijel , Golubovic Snezana , Stojadinovic Ninoslav
Published: February 2014

The behaviour of oxide and interface defects in n-channel power vertical
double-diffused metal-oxide-semiconductor field-effect transistors, firstly
degraded by the gamma-irradiation and electric field and subsequently
recovered and annealed, is presented. By analyzing the transfer
characteristic shifts, the changes of threshold voltage and underlying
changes of gate oxide and interface trap densities during the stress
(recovery, annealing) of investigated devices, it is shown that these two
types of stress influence differently on the gate oxide and the SiO2-Si
interface.
Orexinergic Activation of Medullary Premotor Neurons Modulates the Adrenal Sympathoexcitation to Hypothalamic Glucoprivation
Authors: Korim Willian S. , Bou Farah Lama , McMullan Simon , Verberne Anthony J.M.
Published: February 2014

Glucoprivation activates neurons in the perifornical hypothalamus (PeH) and in the rostral ventrolateral medulla (RVLM), which results in the release of adrenaline. The current study aimed to establish 1) whether neuroglucoprivation in the PeH or in the RVLM elicits adrenaline release in vivo and 2) whether direct activation by glucoprivation or orexin release in the RVLM modulates the adrenaline release. Neuroglucoprivation in the PeH or RVLM was elicited by microinjections of 2-deoxy-d-glucose or 5-thio-d-glucose in anesthetized, euglycemic rats. Firstly, inhibition of neurons in the PeH abolished the increase in adrenal sympathetic nerve activity (ASNA) to systemic glucoprivation. Secondly, glucoprivation of neurons in the PeH increased ASNA. Thirdly, in vivo or in vitro glucoprivation did not affect the activity of RVLM adrenal premotor neurons. Finally, blockade of orexin receptors in the RVLM abolished the increase in ASNA to neuroglucoprivation in the PeH. The evoked changes in ASNA were directly correlated to levels of plasma metanephrine but not to normetanephrine. These findings suggest that orexin release modulates the activation of adrenal presympathetic neurons in the RVLM.
Gut Microbiota Metabolites of Dietary Lignans and Risk of Type 2 Diabetes: A Prospective Investigation in Two Cohorts of U.S. Women
Authors: Sun Qi , Wedick Nicole M. , Pan An , Townsend Mary K. , Cassidy Aedin , Franke Adrian A. , Rimm Eric B. , Hu Frank B. , van Dam Rob M.
Published: February 2014

OBJECTIVE

To examine urinary levels of enterolactone and enterodiol, intestinal microbial metabolites of dietary lignans, in relation to type 2 diabetes (T2D) risk.

RESEARCH DESIGN AND METHODS

Urinary concentrations of the lignan metabolites were assayed by liquid chromatography-mass spectrometry among 1,107 T2D and 1,107 control subjects in a nested case-control study conducted in participants from the Nurses’ Health Study (NHS) and NHSII. Subjects were free of diabetes, cardiovascular disease, and cancer at urine sample collection in 1995–2001. Incident self-reported T2D cases identified through 2008 were confirmed with a validated questionnaire.

RESULTS

In both cohorts, T2D subjects had significantly lower concentrations of both enterolactone and enterodiol than control subjects. After multivariate adjustment for lifestyle and dietary risk factors of T2D, urinary concentrations of enterolactone were significantly associated with a lower risk of T2D (pooled odds ratio [OR] comparing the extreme quartiles 0.62 [95% CI 0.44, 0.88], P for trend = 0.003). Higher urinary concentrations of enterodiol were also marginally significantly associated with a lower T2D risk (pooled OR comparing extreme quartiles 0.67 [95% CI 0.48, 0.96], P for trend = 0.08). When concentrations of both metabolites were combined to reflect total lignan intake, the OR was 0.70 (95% CI 0.53, 0.92) for each SD increment of total lignan metabolites.

CONCLUSIONS

These results indicate that lignan metabolites, especially enterolactone, are associated with a lower risk of T2D in U.S. women. Further studies are needed to replicate these findings and to explore potential mechanisms underlying the observed association.
The variability of body composition characteristics in pre- and postmenopausal women from Slovakia
Authors: Danková Zuzana , Siváková Daniela , Luptáková Lenka , Cvíčelová Marta , Čerňanová Veronika
Published: February 2014

Various changes in body composition and body fat distribution are accompaniments of biological ageing, presented mostly in the middle age and significantly notable during the menopause transition. This study aimed to examine the effect of menopausal status on body composition characteristics in 368 apparently healthy women aged 38–61 years. Bioelectrical parameters were measured with a bioimpedance monofrequency analyser (BIA 101) and bioelectric impedance vector analysis (BIVA) was used to analyse tissue electric properties. Data dealing with menopausal status and symptoms as well as life style variables were obtained by the Menopause specific questionnaire.

Statistical analysis adjusted for age did not show differences either in the body composition characteristics or in the nutrition and obesity indices between pre– and post–menopausal women. Regression analyses pointed on statistically significant effect (p<0.05) of physical exercise on Xc (B=2.353), FM % (B=–1.746) and MM % (B=1.201), of hypertension on R (B=–22.381), FM % (B=4.468), MM % (B=–2.306), of smoking on Xc (B=1.835), FM % (B=–1.227), MM % (B=0.767), of muscle and joint ache on the FM % (B=1.923) and on MM % (B=–1.061). The age had impact on Xc (B=–13.468) and on the phase angle (B=–1.320).

To conclude, in our study group of pre- and postmenopausal Slovak women, age, health and life style factors seem to have more important effect on the body composition characteristics than menopausal status alone.
Is the secular trend reflected in early stages of human ontogenesis?
Authors: Domagała Zygmunt , Dąbrowski Paweł , Porwolik Michał , Porwolik Krystian , Gworys Bohdan
Published: February 2014

There are a limited number of studies on secular changes in the neonatal period, and the majority of them concern research related to childhood and puberty The objective of our study was to carry out a comparative analysis of body weight and length at birth in neonates born in Wrocław in subsequent decades since 1950 to find out if these parameters are subject to secular trend, and what values they attained during the studied period of 50 years.

The study was carried out in the 1950s, 1960s, 1970s, 1980s, 1990s and in 2000 to analyse changes in body length, body weight and Rohrer index over time. The sample studied consisted of 7510 neonates, 3882 males and 3628 females, born in Wroclaw. Secular changes were tested using one-way variance analysis. The values of F statistics were compared to the critical values of the F Snedecor distribution. Changes in the features of neonates in subsequent study years were analysed using the modified z-score. Data were normalised for standard deviation in decade increments.

Results demonstrated very slight, though statistically insignificant increase in body weight at birth. Over the 50-year period the mean body weight of neonates was in the range of 3.3–3.4 kg, regardless of sex. Results demonstrated very slight, though statistically insignificant increase in body weight at birth. Over the 50-year period the mean body weight of neonates was in the range of 3.3–3.4 kg, regardless of sex. The acceleration in the body length of neonates caused a gradual decrease in the mean values of the Rohrer index.

No secular trend in body weight was found in Wrocław neonates over the 50-year period between 1950 and 2000 With regard to body length at birth, four waves of deceleration and acceleration were found: period 1 (1950s): deceleration in the increase of the analysed body parameters of neonates; period 2 (1960s): acceleration in neonates’ growth; period 3 (1970s and 1980s): economic crisis and political transformations in Poland; this is reflected by the stable mean values of body dimensions in neonates. The secular trend clearly decelerated, and period 4 (1990s and 2000) – very intense acceleration in both body weight and length and the Rohrer index.
The human bone oxygen isotope ratio changes with aging
Authors: Stepańczak Beata , Szostek Krzysztof , Pawlyta Jacek
Published: February 2014

The oxygen isotope ratio (δ18O) in tissues is the outcome of both climatic and geographical factors in a given individual’s place of abode, as well as the physiology and metabolism of his organism. During an individual’s life, various rates and intensities of physiological and metabolic processes are observable in the organism, also within the bone tissue.

The aim of this study is to verify whether involutional changes occurring as a result of the organism’s ageing have a significant impact on δ18O determined in the bone tissue.

The material used for analysis was fragments of the long bones taken from 65 people, (11 children and 54 adults), whose remains had been uncovered at the early mediaeval (X–XI century) cemetery located at the Main Market Square in Kraków (Poland).

The correlation analysis between δ18O of bone tissue and an individual’s age shows that up to 40 years of age, such a relationship does not exist in both, males and females. However, the conducted correlation analysis prompted the observation that after 40 years of life, δ18O in bone tissue significantly drops as females increase in age.

Results suggest that the δ18O in bone tissue among older people may be the outcome not only of environmental factors but also involutional changes in bone linked to an organism’s ageing. Therefore, the interpretation of δ18O results relating to the description of the origin and migrations of older individuals should be treated with caution.
Gender independent kids: A paradigm shift in approaches to gender non-conforming children
Authors: Pyne Jake
Published: February 2014

Recent years have seen a substantial change in how children who challenge gender norms (referred to in this article as “Gender Independent”) are regarded by professionals, by their families and by the public at large. Pathologized and treated for decades as a mental illness, childhood gender non-conformity would seem to be imbued with new meaning, as evidenced by a growing number of public voices claiming gender variance as part of human diversity. Call it a paradigm shift: from disorder to diversity, from treatment to affirmation, from pathology to pride, from cure to community. This commentary article reflects on recent shifts in language, shifts in identity options, and shifts in the focus of intervention with gender non-conforming children. Drawing on existing research and public discourse, I consider what the field of human sexuality can learn from “Gender Independence.”
Evaluation of a Primary-Care Setting at a Veterinary Teaching Hospital by a Student Business Group: Implementing Business Training Within the Curriculum
Authors: Poon W. Y. Louisa , Covington Jennifer P. , Dempsey Lauren S. , Goetgeluck Scott L. , Marscher William F. , Morelli Sierra C. , Powell Jana E. , Rivers Elizabeth M. , Roth Ira G.
Published: February 2014

This article provides an introduction to the use of students' business skills in optimizing teaching opportunities, student learning, and client satisfaction in a primary health care setting at a veterinary teaching hospital. Seven veterinary-student members of the local chapter of the Veterinary Business Management Association (VBMA) evaluated the primary-care service at the University of Georgia (UGA) veterinary teaching hospital and assessed six areas of focus: (1) branding and marketing, (2) client experience, (3) staff and staffing, (4) student experience, (5) time management, and (6) standard operating procedures and protocols. For each area of focus, strengths, weaknesses, opportunities, and threats were identified. Of the six areas, two were identified as areas in need of immediate improvement, the first being the updating of standard operating protocols and the second being time management and the flow of appointments. Recommendations made for these two areas were implemented. Overall, the staff and students provided positive feedback on the recommended changes. Through such a student-centered approach to improving the quality of their education, students are empowered and are held accountable for their learning environment. The fact that the VBMA functions without a parent organization and that the primary-care service at UGA functions primarily as a separate entity from the specialty services at the College of Veterinary Medicine allowed students to have a direct impact on their learning environment. We hope that this model for advancing business education will be studied and promoted to benefit both veterinary education and business practice within academia.
Evaluation of Axle-Based and Length-Based Vehicle Classification Stations
Authors: Kim Seoungbum , Coifman Benjamin
Published: February 2014

This study evaluated the performance of three permanent vehicle classification stations on freeways against concurrent video-based ground truth. All stations had dual loop detectors and a piezoelectric sensor in each lane, which together provided axle-based and length-based classification. Evaluation was done at individual, per vehicle resolution for each vehicle that passed during the study periods (more than 18,000 vehicles in uncongested conditions). Although the stations exhibited good performance overall (97% correct), the performance for trucks was poor; for example, only 60% of the single-unit trucks (SUTs) were correctly classified. All observed errors were diagnosed. Some errors could be fixed quickly, and others could not. Data from one site were used to revise the classifier to solve almost all fixable errors, and then performance at another location was tested. A chronic error found in the research was intrinsic to the vehicle fleet and may be impossible to correct with existing sensors: the shorter SUTs have a length range and axle spacing range that overlap those of passenger vehicles. Depending on calibration, SUTs may be counted as passenger vehicles or vice versa. Such errors should be expected at most classification stations. All subsequent uses of the classification data must accommodate this unavoidable blurring error. Because of the blurring, the axle classification station cannot be uncritically used to calibrate the boundary between passenger vehicles and SUTs for length-based classification stations, because unavoidable errors in axle-based classification would be amplified in the length-based classification scheme.
Length-Based Vehicle Classification Schemes and Length Bin Boundaries
Authors: Weinblatt Herbert , Minge Erik , Petersen Scott
Published: February 2014

Vehicle classification data are an important component of traffic-monitoring programs. Although most vehicle classification conducted in the United States is axle based, some applications could be supplemented or replaced by length-based data. The typically higher deployment cost and reliability issues associated with collecting axle-based data as compared with length-based data present a challenge. This paper reports on analyses of alternative length-based vehicle classification schemes and appropriate length bin boundaries. The primary analyses use data from a set of 13 Long-Term Pavement Performance weigh-in-motion sites, all in rural areas; additional analyses are conducted with data from 11 Michigan Department of Transportation weigh-in-motion sites located in rural and small urban areas and one site located in an urbanized area. For most states, the recommended length-based vehicle classification scheme is a four-bin scheme (motorcycles, short, medium, and long) with an optional very long bin recommended for use by states in which significant numbers of longer combination vehicles operate.
Tablet-Based Traffic Counting Application Designed to Minimize Human Error
Authors: Toth Christopher , Suh Wonho , Elango Vetri , Sadana Ramik , Guin Angshuman , Hunter Michael , Guensler Randall
Published: February 2014

Basic traffic counts are among the key elements in transportation planning and forecasting. As emerging data collection technologies proliferate, the availability of traffic count data will expand by orders of magnitude. However, availability of data does not always guarantee data accuracy, and it is essential that observed data are compared with ground truth data. Little research or guidance is available that ensures the quality of ground truth data with which the count results of automated technologies can be compared. To address the issue of ground truth data based on manual counts, a manual traffic counting application was developed for an Android tablet. Unlike other manual count applications, this application allows data collectors to replay and toggle through the video in supervisory mode to review and correct counts made in the first pass. For system verification, the review function of the application was used to count and recount freeway traffic in videos from the Atlanta, Georgia, metropolitan area. Initial counts and reviewed counts were compared, and improvements in count accuracy were assessed. The results indicated the benefit of the review process and suggested that this application could minimize human error and provide more accurate ground truth traffic count data for use in transportation planning applications and for model verification.
Quality Counts for Pedestrians and Bicyclists
Authors: Turner Shawn , Lasley Philip
Published: February 2014

As pedestrian and bicyclist monitoring increases among public agencies, data quality principles must be included in data collection practices. This paper outlines key quality assurance principles and their application to pedestrian and bicyclist traffic count data. Three key principles of quality assurance are described: (a) quality assurance starts before data are collected, (b) acceptable quality is determined by the data's use, and (c) measures can quantify varying quality dimensions. Recommendations are made for two data quality measures: accuracy and validity.
Toward a Flexible System for Pedestrian Data Collection with a Microsoft Kinect Motion-Sensing Device
Authors: Charreyron Samuel , Jackson Stewart , Miranda-Moreno Luis F.
Published: February 2014

Data on pedestrian activity, including volumes, walking speed, and trajectories, are used by transportation agencies and researchers for planning, design, and analysis. Several technologies are available for automatic collection of pedestrian data; however, all have inherent limitations in either functionality or monetary cost. Also, most technologies provide only counts. This paper proposes the use of an inexpensive motion-sensing device, Microsoft Kinect, which can track multiple people in low light conditions and can be combined with existing video-based daytime tracking. The tracking software and speed estimation methodologies are described, and indoor and outdoor studies show the system's effectiveness at determining pedestrian volumes and walking speeds. The accuracy of speed data is very satisfactory, with correlation of 98% or more for video data validation speeds. The accuracy of pedestrian volume data varies with traffic conditions; however, in low to moderate traffic conditions its performance is acceptable, with an undercounting error near 8%. The applications of the sensor and its complementarity with other sensors are discussed, as these are the first step toward a multisensor system.
Estimating Annual Average Daily Bicyclists
Authors: Nordback Krista , Marshall Wesley E. , Janson Bruce N. , Stolz Elizabeth
Published: February 2014

Cities around the United States are investing in bicycle infrastructure, and to secure additional transportation funding, cities are reporting bicycle use and safety improvements. Data on bicyclist traffic volume is necessary for performing safety studies and reporting facility use. Meeting the need for data, available manual bicycle counting programs count cyclists for a few hours per year at designated locations. A key issue in the design of counting programs is determining the timing and frequency of counts needed to obtain a reliable estimate of annual average daily bicyclists (AADB). In particular, in which days of the week, hours of the day, and months of the year should counts be collected? And, most important to program cost, how many hours should be counted? This study used continuous bicycle counts from Boulder, Colorado, to estimate AADB and analyze the estimation errors that would be expected from various bicycle-counting scenarios. AADB average estimation errors were found to range from 15% with 4 weeks of continuous count data to 54% when only 1 h of data was collected per year. The study found that the most cost-effective length for short-term bicycle counts is one full week when automated counting devices specifically calibrated for bicycle counting are used. Seasons with higher bicycle volumes have less variation in bicycle counts and thus more accurate estimates.
Correlation-Based Clustering of Traffic Data for the Mechanistic–Empirical Pavement Design Guide
Authors: Mai Derong , Turochy Rod E. , Timm David H.
Published: February 2014

Development of traffic data clusters is crucial for use of the Mechanistic–Empirical Pavement Design Guide (MEPDG) when site-specific traffic data are not available and statewide data are too general. However, a preferred approach to traffic data clustering is not specified in the MEPDG. In current clustering practice, subjective decisions are made about issues such as determination of the number of clusters. This paper presents a new clustering combination method, correlation-based clustering, that considers the effects of traffic inputs on pavement design thicknesses, so that determination of the number of clusters is made objectively. For each traffic input required in the MEPDG, the similarity between two sites is evaluated with Pearson's correlation coefficient. Then, this approach evaluates the sensitivity of pavement design thickness to each traffic input to quantify locations to cut the hierarchical clustering trees, which objectively determines the number of clusters. The MEPDG requires many traffic inputs, including vehicle class distributions, four types of axle load spectra (per vehicle class), monthly and hourly distribution factors, and distributions of axle groups per vehicle. This clustering approach is performed for each traffic input so that a unique set of clusters can be developed for each traffic input. The method has been implemented for 22 direction-specific weigh-in-motion stations in Alabama to identify clusters of sites with similar estimated pavement performance for each traffic input of the MEPDG. This paper illustrates the clustering process for one traffic input (single-axle distribution) and presents clustering results for vehicle class distribution.
Hybrid Approach for Clustering Vehicle Classification Data to Support Regional Implementation of the Mechanistic–Empirical Pavement Design Guide
Authors: Reimer Mark , Regehr Jonathan D.
Published: February 2014

This paper develops a hybrid approach for analyzing vehicle classification data and applies the approach to a fused data set from multiple jurisdictions in the Canadian prairie region. Application of the approach results in a set of regional default truck traffic classification groups for use in the Mechanistic–Empirical Pavement Design Guide. The hybrid approach is a conglomeration of three components: statistical clustering procedures, expert judgment, and industry intelligence. By applying the hybrid approach, analysts receive the joint benefits of analytical rigor and industry-oriented pragmatism. Application of this approach results in eight truck traffic classification groups for the Canadian prairie region that exhibit distinct differences from the default distributions developed for national use in the United States. The benefits of applying the hybrid approach on fused data sets include (a) the statistical strength gained from use of additional classification data, (b) the development of truck traffic classification groups that better reflect the diversity of patterns in a region, and (c) the potential for improved ability to capture future shifts in truck traffic characteristics because of experience gained in other jurisdictions. The paper also identifies limitations to the hybrid approach that should be considered. These limitations include varying data quality between jurisdictions, the sensitivity of low-volume sites to changes in industry patterns and the ability to track these changes, and potential shortages of continuous classification sites. When its benefits and limitations are well understood, the hybrid approach can be applied to truck traffic data analyses in any jurisdiction.
Impact of Various Trucks on Pavement Design and Analysis
Authors: Selezneva Olga , Ramachandran Aditya , Mustafa Endri , Carvalho Regis
Published: February 2014

This investigation assessed the sensitivity of Mechanistic–Empirical Pavement Design Guide (MEPDG) outcomes to normalized axle load spectra representing various loading conditions observed in the Specific Pavement Studies Transportation Pooled Fund Study of the Long-Term Pavement Performance program. The goal was to determine what vehicle classes and axle types with a wide range of axle loading conditions are likely to cause differences in pavement design outcomes when the MEPDG is used. Significant differences found in the MEPDG outcomes support the need for characterization of axle loading beyond a single default value for heavy trucks that dominate vehicle class distributions, especially for Class 9 trucks. The absence of differences for lightweight and under-represented trucks indicates that load spectra from various sites could be combined to develop a single default for some vehicle classes and axle types. The effect of bias in weigh-in-motion (WIM) axle weight measurements on the normalized axle load spectra estimates and the associated MEPDG outcomes was also investigated. It was found that drift in WIM system calibration leading to a more than 5% bias in mean error between true and WIM-measured axle weight could lead to significant differences in MEPDG design outcomes. These results were used to develop recommendations for creating axle loading defaults for the MEPDG.
Macroscopic Fundamental Diagram for Urban Streets and Mixed Traffic
Authors: Xie Xiaoyan , Chiabaut Nicolas , Leclercq Ludovic
Published: February 2014

In the past decade many papers focused on describing the vehicular traffic stream of an arterial on an aggregate level. Unfortunately, in this considerable body of research, only a few papers account for bus systems. This paper tries to fill that gap by investigating two potential methods for estimating macroscopic fundamental diagrams of multimodal transport systems of a signalized arterial. The first approach models the motion of buses endogenously by extending the existing estimation method with the moving bottleneck theory; the second approach proposes to incorporate the effects of buses exogenously. The estimated macroscopic fundamental diagrams were then cross compared with results provided by microsimulation software that finely reproduced the traffic stream. Mean speeds of vehicles and buses produced by the different methods were similar and consistent. Finally, results of the three methods were expressed for levels of service and compared with the levels of service of the Highway Capacity Manual 2010.
Comparing Calibrated Shared Space Simulation Model with Real-Life Data
Authors: Rudloff Christian , Schönauer Robert , Fellendorf Martin
Published: February 2014

Shared spaces are being implemented in many countries to deal with safety concerns and traffic flow problems on busy urban streets and street crossings. However, shared space concepts could not be tested before they were built because of the lack of a functioning microscopic shared space simulation. Lane-based car-following models, currently used in traffic simulation, cannot reproduce the high heterogeneity of a mixed traffic mode's nonchannelized flow. This paper's novel approach introduces an extended social force model for vehicles and pedestrians that incorporates social interactions between different modes of transport rather than following a purely rule-based approach. The calibration of such a microscopic traffic simulation model with real-world data from two shared space sites is presented. The simulation can reproduce real-life shared space behavior by comparing it with trajectory and interaction data collected at implemented shared space road designs.
Green Light Optimized Speed Advisory Systems
Authors: Stevanovic Aleksandar , Stevanovic Jelka , Kergaye Cameron
Published: February 2014

The highest fuel consumption on urban arterials is associated with driving in congested traffic, characterized by higher speed fluctuations and frequent stops at intersections. One way to reduce excessive stop-and-go driving on urban streets is to optimize signal timings. More recently, new methods in traffic signal optimization have incorporated changes in drivers' behavior to achieve optimum performance at signalized intersections. Connected vehicles technology provides a two-way wireless communication environment enabling vehicle-to-vehicle and vehicle-to-infrastructure communications, which can be used for a variety of mobility and safety applications. One such application is called the green light optimized speed advisory (GLOSA). This system uses timely and accurate information about traffic signal timing and traffic signal locations to guide drivers (through infrastructure-to-vehicle communication) with speed advice for a more uniform commute with less stopping time through traffic signals. A GLOSA implementation was evaluated for two types of traffic signal timing: predictable fixed-time signal timing and unpredictable actuated–coordinated signal timing. A two-intersection traffic network was modeled in VISSIM to achieve trustworthy results calibrated in the field. A comprehensive modal emission model was used to accurately estimate emissions. Experiments included various infrastructure-to-vehicle penetration rates and GLOSA activation frequencies. Results indicated that actuated–coordinated signal timings were not dependable for use in GLOSA systems. For fixed-time signals, higher penetration rates and more frequent GLOSA activations resulted in better traffic performance. GLOSA caused only minor improvements in fuel consumption, and average delay in vehicles stopped was improved significantly.
Inhomogeneous Flow Patterns in Undersaturated Road Networks
Authors: Doig Jean C. , Gayah Vikash V. , Cassidy Michael J.
Published: February 2014

Travel conditions on a road network are described by a macroscopic fundamental diagram (MFD) only when traffic is homogeneously distributed over all of the network's links. Otherwise, a network's measured traffic states fall beneath its MFD, and network flow therefore falls below the maximum. The present study found that inhomogeneous link flowed in a network may emerge before the beginning of a peak period, even before persistent queues had formed. This finding is potentially problematic because it is known that inhomogeneities of this kind can persist in a network for long durations. Therefore, the inhomogeneities that are predicted for undersaturated traffic conditions may persist as the network moves to the brink of congestion, and even well beyond. If drivers are left to their own devices, a network will never serve its peak period demand at the maximum rate. Steady state conditions in under-saturated networks of signalized intersections were modeled in simple ways. Analyses were performed for an idealized street grid characterized by uniform origin–destination patterns and a more realistic demand pattern that resembles one in downtown San Francisco, California. Emergent patterns in inhomogeneous link flow were examined. Preliminary ideas to combat these undesirable patterns are discussed.
Making NGSIM Data Usable for Studies on Traffic Flow Theory
Authors: Montanino Marcello , Punzo Vincenzo
Published: February 2014

Despite the importance of NGSIM data for research on traffic flow theory, these data proved to be massively affected by measurement errors in the vehicle's spatial coordinates, errors that were further amplified in the differentiation process when speed and acceleration values were calculated. If not properly accounted for, these errors would make NGSIM data unusable for any study on traffic flow theory. However, the techniques applied in the literature to correct vehicle trajectory data are not suitable for the scope; these techniques do not treat the cause of the bias appropriately and are limited to smoothing out the effects, which are the high-and medium-frequency disturbances in the data. Therefore, in this study the mechanism that was the root of the NGSIM data errors was illustrated, and the limits of available techniques were shown. Then, clarification that extremely high errors, the outliers, need special treatment to be fixed was provided. A multistep filtering procedure aimed at (a) eliminating outliers giving rise to unphysical values for acceleration by local reconstruction of the vehicle trajectory and (b) cutting off the residual random disturbances from the signal while still preserving the driving dynamics was proposed. Both operations were performed, with the requirement for internal consistency of the trajectory being taken into account. Results related to a single vehicle's trajectory from the NGSIM I-80 data set and results from the application to the complete set of trajectories from the same data set are presented. The results necessitated correction of NGSIM data before further processing.
New Car-Following Model considering Impacts of Multiple Lead Vehicle Types
Authors: Aghabayk Kayvan , Sarvi Majid , Forouzideh Nafiseh , Young William
Published: February 2014

In the past decade, the development and the application of traffic micro-simulation to replicate real-world traffic behavior have become pervasive among traffic and transport researchers. The modeling of a driver's car-following behavior, which forms the fundamental component of traffic microsimulation, has meanwhile been an important research direction leading to the sophistication of traffic microsimulation. However, recent studies have pointed out that a driver's following behavior varies when the lead vehicle is a passenger car as opposed to a heavy vehicle. Nevertheless, existing models do not precisely address those differences. This oversight could diversely affect the accuracy of traffic microsimulations, particularly with the current trend of an increasing number of heavy vehicles in the traffic stream. A novel car-following model that considered the heterogeneity of lead vehicles was developed. Two types of lead vehicles were considered in this study: passenger cars and heavy vehicles. The model was developed on the basis of the local linear model tree approach. This approach is able to incorporate human perceptual imperfections into a car-following model. The input space is partitioned incrementally, and a linear model is developed for each locality (partition). The final output is calculated by the fuzzy combination of local models according to the validity function of each model. For training and testing purposes, two real-world data sets were obtained from a U.S. freeway under congested traffic conditions. The results showed very close agreement between the real data and the outputs of the proposed model.
On Observable Chaotic Maps for Queuing Analysis
Authors: Chow Joseph Y. J.
Published: February 2014

A queuing model based on chaotic mapping offers a number of distinct advantages over stochastic and constant deterministic models. Depending on the type of chaotic map used, such a queue can capture transient behavior, intermittency, steady state behavior, and complex distributions in arrival rates. These characteristics are especially desirable in many queuing applications in transportation. Earlier studies resulted in chaotic queuing models that cannot be estimated by using observed arrivals. An alternative queuing model is presented along with methods to specify the model, interpret its results, and estimate its parameters. The proposed queuing model used chaotic maps of interarrival times to generate arrivals so that parameters could be calibrated with observable data. A sample queue based on the ergodic logistic map is presented. For the calibration of the mapping on the basis of observed data, the method of successive averages was used with a joint parameter and state estimation algorithm. Two connected queues illustrated how a purely deterministic queuing network could still result in a joint invariant distribution. The results offer a positive view of this method and its applicability to queuing problems, particularly in the field of transportation and dynamic network loading.
Reconfigured Temporalities Nature's Intent?
Authors: Blanc Nathalie , Sander Agnès
Published: February 2014

Speculative fiction as a literary genre is a test of the renewed relation to nature presented as possible reality. The vision of nature presented by some science fiction and fantasy authors varies along these lines. The hypothesis underlying the present article is that these "speculative fiction–proposed natures" force us to rethink the rapport between time and space. Therefore, we need to examine to what extent science fiction and fantasy, focused on the preparation of an uncertain future, play on the links between time and nature and reconfigure both the agencies and the aesthetic situations that serve as experiments.
“Evidences of Decadent Humanity”: Antianthropocentrism in Early Science Fiction
Authors: Moore Bryan L.
Published: February 2014

Early science fiction (SF) is noted for, among other things, its conservatism and lack of interest in ecology. Brian Stableford, a well-known SF writer and critic, writes that "there are very few early stories with ecological themes" (1993, 395). This article shows that, in fact, many early SF works (those written between the Enlightenment and World War II) employ ecological themes, especially as applied to questioning our anthropocentrism. These works suggest that humans are but one species among many, that we are not the end of nature/history, that the natural world may be better off without us, and, in some cases, that humanity is fated to go extinct, the result of its own hubris. Such views are undoubtedly pessimistic, yet these works may also be read as warnings for humans to seek a more humble view of ourselves as members of what Aldo Leopold calls the land community.
Mechanisms of Risk Production in Modern Cities
Authors: Büscher Christian , Mascareño Aldo
Published: February 2014

Historically, risk assessment and the concept of risk itself have been dominated by environmental, engineering, and economic sciences. Consequently, in analyzing risk production in modern cities, a rather technical view emerges on risks and urban dynamics. Though scientifically grounded and practically useful, this view fails to capture the social complexity of the city, its paradoxes and causalities. Elaborating on the hypothesis that the life-supporting mechanisms in modern cities are simultaneously life-endangering mechanisms, the article aims to develop a sociological framework to comprehend the dynamics of systematic risk production in the urban milieu. Methodologically, to illustrate the functioning of such mechanisms, we will use historical references and several empirical analyses related to urban research.
Innate Immune Functions in hen Reproductive Organs
Authors: Yoshimura Yukinori , Mageed Ahmad M. Abdel , Nii Takahiro , Ariyadi Bambang , Isobe Naoki
Published: February 2014

The ovary and oviduct of the hen are susceptible to various pathogenic microorganisms, and infections in these organs may not only contaminate the eggs, but also disorder the egg formation. The immune function of the ovary and oviduct is essential to protect these tissues from infection as well as for the production of hygienic eggs. This paper reviews recent studies on the host defence system in the reproductive organs with reference to their innate immune functions, with emphasis on the important role of Toll-like receptors and avian β-defensins in this defence system.
A Review of Strategies for Producing Chimeric Birds
Authors: Yan L. , Gao J.S. , Rui L. , Lu Y.N. , Wan Z.Y. , Yu X.X. , Zhang W.X. , Li H.T. , Shao Q. , Zhang J. , Li Z.D.
Published: February 2014

Avian chimeras have been shown to be very useful tools for studying embryonic development. Blastodermal cells form stage X embryos and primordial germ cells (PGCs) are extensively used in chimera production. Intraspecies and interspecies germline chimeras have been successfully produced by transferring blastodermal cells or PGCs into recipient blastoderm at stage X or into the early embryonic blood. The long-term culture system established using pluripotent cells from birds provides an alternative method for preserving the endangered species source and facilitates the manipulation of avian transgenesis. A high rate of donor cell-derived progeny production has always been pursued by germline chimera studies. However, the rate of progeny production was unstable. Different methods have been used in an attempt to improve the efficiency of germline chimera production. Several methods have been shown to greatly enhance the efficiency of donor cell-derived progeny production. In this review, we focus on the strategies used for germline chimera production in birds and discuss the factors and measures affecting the efficiency of obtaining donor cell-derived progeny.
Non-classical Signalling of Growth Hormone in the Chick Neural Retina?
Authors: Harvey Steve , Baudet Marie-Laure , Luna Maricela , Aramburo Carlos
Published: February 2014

Growth hormone (GH) signalling is traditionally via a ‘classical’ GH-receptor (GHR) that is present in the plasma membrane of target cells. GHRs are present in the neural retina of early chick embryos (within the first trimester of incubation) but these are unlikely to be endocrine target sites of GH action, as pituitary GH is not secreted into the bloodstream until late in development (approximately day 17 of the 21 days incubation period) and because the blood–ocular barrier would block the entry of systemic GH into the retina. As GH is expressed in the early neural retina, retinal GHRs are thus likely to be autocrine or paracrine sites of GH action. The most abundant GH moieties in the neural retina are, however, unlikely to activate ‘classical’ GHRs in the neural retina, as they are submonomeric molecules (of 15 kDa and 16.5 kDa) that fail to bind to plasma membrane receptor (15 kDa GH) or lack the stoichiometric requirements likely required for GHR binding (16.5 kDa GH). Nevertheless, 15 kDa GH is biologically active in chicks and the immunoneutralisation of endogenous 16.5 kDa GH induces biological activity. It is therefore possible that GH in the neural retina of early chick embryos acts non-classically or via ‘non-classical’ GHRs. These possibilities are the focus of this brief review.
Relationship between Glucose and Pancreatic Hormones during the Embryonic and Postnatal Phase in Chickens
Authors: Franssens Lies , Buyse Johan , Decuypere Eddy , Everaert Nadia
Published: February 2014

Insulin plays a vital role in the regulation of glucose levels in the bloodstream. Chickens have similar circulating insulin concentrations compared to mammals but still maintain high plasma glucose levels. This phenomenon may be a consequence of the development of insulin resistance early in posthatch life, which may be the result of pertubations in the insulin signalling cascade. In addition, our study demonstrates that the response of plasma glucose and the hepatic glucose transporter 2 mRNA to insulin in broiler chicks during the perinatal period is age-dependent. This review addresses the relationship between glucose and pancreatic hormones in embryonic and posthatch stages in the life cycle of the domestic chicken.
Incidence and Biology of Corynespora cassiicola (Berk. & Curt.) Wei. disease of okra in Bangladesh
Authors: Ahmed Fakhruddin Ali , Alam Nazmul , Khair Abul
Published: February 2014

Eight commercial okra cultivars were evaluated to determine the magnitude of incidence of Corynespora cassiicola (Berk. & Curt.) Wei. Maximum and significant incidence of C. cassiicola was 14.86 in the cultivar BARI 1. In rest of the cultivars, the occurrence of this fungus was very poor to nil. Corynespora cassiicola appeared to be a minor pathogen for okra. Effects of temperature, pH and culture media on growth and sporulation of the fungus were investigated. Potato dextrose agar medium was found to be the most suitable for optimum growth and sporulation of this fungus at pH 7 and 25ºC. The conidial length significantly varied with the changes of pH. The correlation between pH and conidial length was found negative and highly significant. DOI: http://dx.doi.org/10.3329/bjb.v42i2.18028 Bangladesh J. Bot. 42(2): 265-272, 2013 (December)
Effects of leaf and plant age on specific leaf area in deciduous tree species Quercus cerris L. var. Cerris
Authors: Karavin Neslihan
Published: February 2014

In Quercus cerris L. var. cerris, four diameters at breast height (BDH) groups were selected as a surrogate for approximate plant age groups to study the effects of plant and leaf age on leaf dry mass, leaf area and specific leaf area. The forms of fluctuations in specific leaf area (SLA) of all DBH groups were similar during the growth period. The minimum SLA was calculated at the leaves mature phase. Leaf area did not differ significantly according to leaf age. Significant differences caused by leaf age were determined in mean leaf dry mass and SLA. No significant differences in mean SLA caused by plant age were found. Leaf area and leaf dry mass significantly varied among DBH groups. Leaf area was positively correlated with leaf dry mass, and SLA was negatively correlated with leaf dry mass, while there was no significant relationship with leaf area. DOI: http://dx.doi.org/10.3329/bjb.v42i2.18034 Bangladesh J. Bot. 42(2): 301-306, 2013 (December)
Chemical composition and antioxidant activity of essential oils of three endemic medicinal plants of Iran
Authors: Pirbalouti Abdollah Ghasemi , Sedaghat Leila , Hamedi Behzad , Tirgir Farhang
Published: February 2014

Hydro-distillated essential oils (EO) antioxidant activity of three endemic medicinal plants of Iran namely, Heracleum lasiopetalum Boiss., Kelussia odoratissima Mozaff., and Ferulago angulata (Schlecht.) Boiss were studied. The results indicated that the major components of the EOs were 2-ethylhexyl acetate (34.5%), n-octanol (6.5%), and hexanol (5.1%) for H. lasiopetalum fruits; Z-?-ocimene (20.5), ?-pinene (11.6%), and ?-phellandrene (9.3) for F. angulata aerial parts; ?-pinene (20.1%), 1,8-cineole (18.2%), and Zligustilide (15.5%) for K. odoratissima aerial parts. The three EOs having high antioxidant activity could be used as an alternative preservative instead of synthetic ones in food industry. DOI: http://dx.doi.org/10.3329/bjb.v42i2.18038 Bangladesh J. Bot. 42(2): 327-332, 2013 (December)