bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing migratory connectivity for a long‐distance migratory bird using multiple intrinsic markers
Authors: Rushing Clark S. , Ryder Thomas B. , Saracco James F. , Marra Peter P.
Published: September 2013

Patterns of migratory connectivity are a vital yet poorly understood component of the ecology and evolution of migratory birds. Our ability to accurately characterize patterns of migratory connectivity is often limited by the spatial resolution of the data, but recent advances in probabilistic assignment approaches have begun pairing stable isotopes with other sources of data (e.g., genetic and mark–recapture) to improve the accuracy and precision of inferences based on a single marker. Here, we combine stable isotopes and geographic variation in morphology (wing length) to probabilistically assign Wood Thrush (Hylocichla mustilena) captured on the wintering grounds to breeding locations. In addition, we use known‐origin samples to validate our model and assess potentially important impacts of isotopic and morphological covariates (age, sex, and breeding location). Our results show that despite relatively high levels of mixing across their breeding and nonbreeding ranges, moderate levels of migratory connectivity exist along an east–west gradient. In addition, combining stable isotopes with geographic variation in wing length improved the precision of breeding assignments by 10% and 37% compared to assignments based on isotopes alone or wing length alone, respectively. These results demonstrate that geographical variation in morphological traits can greatly improve estimates of migratory connectivity when combined with other intrinsic markers (e.g., stable isotopes or genetic data). The wealth of morphological data available from museum specimens across the world represents a tremendously valuable, but largely untapped, resource that is widely applicable for quantifying patterns of migratory connectivity.
Nitrapyrin Impacts on Maize Yield and Nitrogen Use Efficiency with Spring‐Applied Nitrogen: Field Studies vs. Meta‐Analysis Comparison
Authors: Burzaco Juan P. , Ciampitti Ignacio A. , Vyn Tony J.
Published: September 2013

In maize (Zea mays L.), low N use efficiency (NUE) is observed when a high proportion of the fertilizer N is not recovered by the crop. Combining different management practices can improve maize NUE. The objectives were to assess the impacts of integrated N management practices on grain yield (GY), plant N uptake (PNU), and NUE (and its components, N recovery efficiency [NRE] and N internal efficiency [NIE]) from three maize site‐years (Indiana). The factors evaluated were: (i) N rate (0, 90, and 180 kg N ha−1), (ii) nitrapyrin (presence or absence), and (iii) N timing (at planting or V6 stage). Grain yields for the field research study ranged from 6.3 to 12.1 Mg ha−1. The main results indicated: (i) PNU increased with N rates and with delayed N timing, (ii) the use of nitrapyrin increased NUE (∼17%), primarily via improving NRE (∼25%), and (iii) NUE increased by delaying the timing of N application. In addition to the field experiments, a meta‐analysis studying the effect of nitrapyrin on maize GY, PNU, and NUE was performed. Highlights from the meta‐analysis were: (i) positive impacts of nitrapyrin application on both GY and PNU, but (ii) those impacts were neither reflected in gains for NUE nor for NRE and NIE. The positive impacts of nitrapyrin on NUE (and components) found in the field research study were not consistent with the outcomes documented in the meta‐analysis. This emphasizes that the potential maize NUE benefits of nitrapyrin addition to spring N applications are not always realized.
Predicting Vertically Nonsequential Wetting Patterns with a Source‐Responsive Model
Authors: Nimmo John R. , Mitchell Lara
Published: September 2013

Water infiltrating into soil of natural structure often causes wetting patterns that do not develop in an orderly sequence. Because traditional unsaturated flow models represent a water advance that proceeds sequentially, they fail to predict irregular development of water distribution. In the source‐responsive model, a diffuse domain (D) represents flow within soil matrix material following traditional formulations, and a source‐responsive domain (S), characterized in terms of the capacity for preferential flow and its degree of activation, represents preferential flow as it responds to changing water‐source conditions. In this paper we assume water undergoing rapid source‐responsive transport at any particular time is of negligibly small volume; it becomes sensible at the time and depth where domain transfer occurs. A first‐order transfer term represents abstraction from the S to the D domain which renders the water sensible. In tests with lab and field data, for some cases the model shows good quantitative agreement, and in all cases it captures the characteristic patterns of wetting that proceed nonsequentially in the vertical direction. In these tests we determined the values of the essential characterizing functions by inverse modeling. These functions relate directly to observable soil characteristics, rendering them amenable to evaluation and improvement through hydropedologic development.
Relationship between Cognitive Function, Depression/Anxiety and Functional Parameters in Patients Admitted for Congestive Heart Failure
Authors: Feola Mauro , Garnero Sonia , Vallauri Paola , Salvatico Luigi , Vado Antonello , Leto Laura , Testa Marzia
Published: September 2013

Cognitive impairment, anxiety and depression have been described in patients with congestive heart failure (CHF). We analyzed in-hospital CHF patients before discharge with neuropsychological tests attempting to correlate with prognostic parameters.

Methods:

All subjects underwent a mini mental state examination (MMSE), geriatric depression scale (GDS), anxiety and depression scale test (HADS). We evaluated NYHA class, brain natriuretic peptide (BNP), left ventricular ejection fraction (LVEF) and non-invasive cardiac output (CO).

Results:

Three-hundred and three CHF patients (age 71.6 ys) were analysed. The mean NYHA class was 2.9±0.8, LVEF was 43.4±15.8%; BNP plasma level and CO were calculated as 579.8±688.4 pg/ml and 3.9±1.1 l/min, respectively. In 9.6% a pathological MMSE score emerged; a depression of mood in 18.2% and anxiety in 23.4% of patients were observed. A significant correlation between MMSE and age (r=0.11 p=0.001), BNP (r=0.64 p=0.03) but not between MMSE and NYHA class and LVEF was observed. GDS and HADS were inversely correlated with NYHA class (r=0.38 p=0.04) and six-minute walking test (r=0.18 p=0.01) without an association with objective parameters in CHF (BNP, LVEF and cardiac output). At multivariate analysis only MMSE and BNP are inversely correlated significantly (p=0.019 OR=-0.64, CI=-042-0.86).

Conclusions:

in-hospital CHF patients may manifest a reduction of MMSE and important anxiety/depression disorders. The results of the study suggest that the presence of cognitive impairment in older CHF patients with higher BNP plasma level should be considered. In admitted CHF patients anxiety and depression of mood are commonly reported and influenced the perception of the severity of illness.
Hybrid photonics structures with grating and prism couplers based on ZnO waveguides
Authors: Struk P. , Pustelny T. , Gołaszewska K. , Kamińska E. , Borysiewicz M. , Ekielski M. , Piotrowska A.
Published: September 2013

This paper presents the results of investigations concerning input-output systems of an electromagnetic wave in the visible and near visible spectrum for their application in structures of integrated optics. The input-output structures used in described planar optical waveguides are in a form of prism and grating couplers. The first part of the paper contains numerical analysis of grating couplers aiming at an optimization of their geometrical parameters, strictly — the depth of the grooves in the grating coupler. The second part presents the practical realization, as well as experimental tests of the planar optical waveguide with the hybrid input-output system. As the input system of the electromagnetic wave, a prism coupler was used, and in the case of the output system — a photonic structure with grating coupler was applied. The investigated planar wave guides with the input-output structures were made of a wide energy band gap semiconductor — zinc oxide (ZnO).
Real time area-based stereo matching algorithm for multimedia video devices
Authors: Hachaj T. , Ogiela M.
Published: September 2013

In this paper we investigate stereovision algorithms that are suitable for multimedia video devices. The main novel contribution of this article is detailed analysis of modern graphical processing unit (GPU)-based dense local stereovision matching algorithm for real time multimedia applications. We considered two GPU-based implementations and one CPU implementation (as the baseline). The results (in terms of frame per second, fps) were measured twenty times per algorithm configuration and, then averaged (the standard deviation was below 5%). The disparity range was [0,20], [0,40], [0,60], [0,80], [0,100] and [0,120]. We also have used three different matching window sizes (3×3, 5×5 and 7×7) and three stereo pair image resolutions 320×240, 640×480 and 1024×768. We developed our algorithm under assumption that it should process data with the same speed as it arrives from captures’ devices. Because most popular of the shelf video cameras (multimedia video devices) capture data with the frequency of 30Hz, this frequency was threshold to consider implementation of our algorithm to be “real time”. We have proved that our GPU algorithm that uses only global memory can be used successfully in that kind of tasks. It is very important because that kind of implementation is more hardware-independent than algorithms that operate on shared memory. Knowing that we might avoid the algorithms failure while moving the multimedia application between machines operating different hardware. From our knowledge this type of research has not been yet reported.
Scapular Kinematics During Shoulder Elevation Performed With and Without Elastic Resistance in Men Without Shoulder Pathologies
Authors: Camci Elif , Duzgun Irem , Hayran Mutlu , Baltaci Gul , Karaduman Ayse
Published: September 2013

Study Design

Controlled laboratory study using within-group comparisons.

Objectives

To compare scapular kinematics between active and resisted shoulder elevation performed in the sagittal (flexion), frontal (abduction), and scapular (scapular abduction) planes.

Background

Several studies have documented scapular kinematics during arm elevation against an external load; however, there is little information on how scapular kinematics change with loading provided by elastic bands, an exercise approach often used in the clinic.

Methods

Thirty-two men without shoulder pathology participated in the study. The level of resistance to be used for each individual was determined prior to data collection and standardized by perceived effort on a Borg scale. Three-dimensional scapular kinematics were recorded with an electromagnetic tracking device in all 3 planes of shoulder elevation for both the unloaded (active) and loaded (resisted) conditions. Data for scapular kinematics were analyzed at 30°, 60°, 90°, and 120° of humerothoracic elevation and lowering. Comparisons between loading conditions were made using analysis-of-variance models.

Results

In general, for all 3 planes of movement, the scapula was more downwardly rotated and anteriorly tilted during the elevation phase and more so during the lowering phase of shoulder elevation when performed against elastic resistance. While some of the statistically significant differences might not have been large enough to be considered clinically meaningful, some values were of a magnitude similar to previously reported differences between healthy and symptomatic individuals.

Conclusions

The changes in scapular motion during the loaded condition were relatively small in this population with normal scapular motion, but they were in a direction that would be considered to have potential to lead to injuries, suggesting caution when using these exercises in individuals with poor scapular control. J Orthop Sports Phys Ther 2013;43(10):735–743. Epub 13 September 2013. doi:10.2519/jospt.2013.4466
A Synthesis of Academic Interventions for Incarcerated Adolescents
Authors: Wexler Jade , Pyle Nicole , Flower Andrea , Williams Jacob L. , Cole Heather
Published: September 2013

This article contains a synthesis of academic intervention studies conducted between 1970 and 2012 with adolescents who were incarcerated in residential juvenile correctional facilities. Literacy, mathematics, written expression, and multicomponent interventions were included if they measured effects on at least one academic outcome measure. Of the 16 studies synthesized, 7 studies employed an experimental or quasi-experimental design, 4 used a single-case design, and 5 used a single-group design. Because the results are restricted due to methodological limitations and a general lack of research in this area, we discuss the existing gaps in the literature and explore initial findings using these 16 studies. Results suggest the potential of implementing explicit, targeted, academic interventions that have previously shown promise with adolescents in the general school setting (e.g., peer-mediated instruction). Implications and guidance for future research regarding effective delivery of evidence-based practices for adolescents in the incarcerated setting are discussed.
Climate change Adaptation and Local Institutions: How to Connect Community Groups with Local Government for Adaptation Planning
Authors: Khatri Dil B , Bista Rajesh , Gurung Niru
Published: September 2013

DOI: http://dx.doi.org/10.3126/jfl.v11i1.8610 Journal of Forestry and Livelihood Vol.11(1) 2013 14-28
Climate Change Adaptation in Nepal: Exploring Ways to Overcome the Barriers
Authors: Regmi Bimal Raj , Bhandari Dinanath
Published: September 2013

DOI: http://dx.doi.org/10.3126/jfl.v11i1.8612 Journal of Forestry and Livelihood Vol.11(1) 2013 43-61
Climate Change and Urban Water Supply: Adaptive Capacity Local Government in Kathmandu City, Nepal
Authors: Jha Prakash K , Shrestha Krishna K
Published: September 2013

DOI: http://dx.doi.org/10.3126/jfl.v11i1.8613 Journal of Forestry and Livelihood Vol.11(1) 2013 62-81
Adaptability in Agriculture and Forestry Activities in Huong Son Commune, Vietnam
Authors: Thang Tran Nam , Dung Ngo Tri , Hoang Nguyen Van
Published: September 2013

DOI: http://dx.doi.org/10.3126/jfl.v11i1.8614 Journal of Forestry and Livelihood Vol.11(1) 2013 82-93
Climate Change and Adaptation: Evidence from a Forest-dependent Community in Bangladesh
Authors: Miah Md Giashuddin , Ahmed Minhaz , Afroz Tahmina
Published: September 2013

DOI: http://dx.doi.org/10.3126/jfl.v11i1.8615 Journal of Forestry and Livelihood Vol.11(1) 2013 94-108
Editorial Vol.11(2)
Authors: Editor The
Published: September 2013

DOI: http://dx.doi.org/10.3126/jfl.v11i2.8616 Journal of Forestry and Livelihood Vol.11(2) 2013
Grassroots Capacity Building for REDD+: Lessons from Nepal
Authors: Luintel Harisharan , Silori Chandra Shekhar , Frick Simone , Poudyal Bishnu Hari
Published: September 2013

Meaningful engagement and effective participation of grassroots stakeholders and forest managing communities in national policy formulation and local institutional processes for forest management have implications for the future global climate regime and poverty reduction among forestdependent poor. In this context, the institutional and technical capacity of grassroots stakeholders is critical in ensuring effective and successful implementation of Reducing Emissions from Deforestation and Forest Degradation, including Conservation and Sustainable Management of Forests and Enhancement of Forest Carbon Stocks (REDD+). Capacity building for grassroots stakeholders is particularly crucial as REDD+ has to be implemented in a complex local environment shaped by multiple land use systems, sharply divided politics, conflicting policies, different levels of forest dependencies, complex social relations, unclear governance and tenure structures and differential climate impacts. It has been learned from the grassroots capacity building programme that there is a need of partnership and collaboration between grassroots stakeholders to build capacity for fighting against climate change at local level. However, there is no ‘one size fits all’ formula for capacity building, partnership and collaboration. Multi-pronged and multi-scale capacity strengthening strategies that draw on the strengths of various learning methods and address the unique needs of targeted stakeholders would be effective. These would/ should always be target-driven, addressing the specific needs and conditions of stakeholders, and reflecting their sustainable development strategies, priorities and initiatives. There is still a need to re-orient and strengthen the capacity of the key stakeholders of REDD+ in Nepal so that they can better analyse and understand their own carbon forestry conditions and develop strategies to get more benefits from the REDD+ scheme.DOI: http://dx.doi.org/10.3126/jfl.v11i2.8617 Journal of Forestry and Livelihood Vol.11(2) 2013 1-13
Social Safeguards in REDD+: A Review of Existing Initiatives and Challenges
Authors: Silori Chandra Shekhar , Frick Simone , Luintel Harisharan , Poudyal Bishnu Hari
Published: September 2013

Reducing emissions from deforestation and forest degradation, as well as conservation and enhancement of forest carbon stocks and promoting sustainable management of forests in developing countries (REDD+) has been proposed as an effective mechanism to mitigate the impacts of climate change. However, in view of the significant dependence of the local communities, indigenous peoples, women and other marginalized groups on the forest resources for their livelihoods and other daily needs, a number of apprehensions have been raised, citing the potential risk associated with the faulty design and weak implementation of the REDD+ mechanism. In this context, a number of international initiatives have been proposing different sets of social and environmental safeguards, which can prevent potential social and/or environmental damage or harm to such forest-dependent communities and increase benefits for them in an equitable manner. By presenting brief overviews of various international level social and environmental safeguards, the authors argue that the initiatives taken so far provide a solid basis for formulating them at national level despite several challenges. There is a need to customize and harmonize the safeguard measures proposed so far with the national level initiatives related to forest/land rights, forest governance, benefits sharing, and so on. Ensuring effective and meaningful participation of local communities and civil society has been identified as challenging prerequisite to address genuine concerns of forest managing communities while developing, implementing and monitoring safeguard provisions. Similarly, allowing utmost important factor – flexibility - in the interpretation and implementation of safeguard provisions at the national and local contexts has to be recognized and managed properly. DOI: http://dx.doi.org/10.3126/jfl.v11i2.8619 Journal of Forestry and Livelihood Vol.11(2) 2013 27-36
Forest Monitoring, Measurement, Reporting and Verification: from Principle to Practice
Authors: Manandhar Ugan
Published: September 2013

Under the United Nations Framework Convention on Climate Change (UNFCCC), many tropical developing countries have agreed to participate in the Reducing Emissions from Deforestation and Forest Degradation as well as conservation and enhancement of carbon stocks and sustainable management of forests (REDD+) programme so as to receive payments for their contribution in reducing emissions from forestry sector. The emission reduction is measured in terms of quantifications of carbon dioxide (CO2) equivalent, upon which payments are made. To quantify emissions in terms of CO2 equivalent, a process called measurement/monitoring, reporting and verification (MRV) has been developed, which forms the backbone of performance-based payment under the REDD+ mechanism. This paper primarily reviews the principles and methods of MRV. By taking the case of the Terai Arc Landscape (TAL) of Nepal, a sub-national level proposed project, the paper demonstrates how an institutional mechanism for MRV can be designed and practiced at national level considering national circumstances and existing institutions. Also, the cost effectiveness and transparency of the MRV process are identified as important elements. DOI: http://dx.doi.org/10.3126/jfl.v11i2.8621   Journal of Forestry and Livelihood Vol.11(2) 2013 46-54
REDD+ Governance, Benefit Sharing and the Community: Understanding REDD+ from Stakeholders’ Perspective in Nepal
Authors: Paudel Govinda , Karki Rahul
Published: September 2013

DOI: http://dx.doi.org/10.3126/jfl.v11i2.8622 Journal of Forestry and Livelihood Vol.11(2) 2013 55-64
Co-Benefits of REDD+ in Community Managed Forests in Nepal
Authors: Joshi Laxman , Karky Bhaskar Singh , Poudel Krishna Chandra , Bhattarai Keshav , Dangi Resham , Acharya Krishna , Uprety Batu , Singh Vijay , Chand Narendra , Manandhar Ugan
Published: September 2013

DOI: http://dx.doi.org/10.3126/jfl.v11i2.8623 Journal of Forestry and Livelihood Vol.11(2) 2013 65-68
REDD+ as a Source of Conflict and Cooperation
Authors: Gritten David , Silori Chandra , Suzuki Regan , Dhiaulhaq Ahmad
Published: September 2013

DOI: http://dx.doi.org/10.3126/jfl.v11i2.8625 Journal of Forestry and Livelihood Vol.11(2) 2013 75-81
Incorporating Intrahousehold Interactions into a Tour-Based Model of Public Transport Use in Car-Negotiating Households
Authors: Ho Chinh , Mulley Corinne
Published: September 2013

Intrahousehold interactions in travel are fundamental to an understanding of activity travel behavior, as reflected by the substantial percentage of regional travel that is made jointly. The development of travel demand models that incorporate intrahousehold interactions is crucial to a credible analysis of traveler response to policies. A tour-based modeling framework is used to examine intrahousehold interactions in travel mode choice with a focus on public transport use in households having differences in car availability. An important distinction is made between car-sufficient households (in which there are at least as many cars in the household as license holders) and car-negotiating households (households that have fewer cars than license holders). Intrahousehold interactions and temporal–spatial constraints are explicitly represented by different patterns of joint household tours, with home-based tours as the unit of analysis. The empirical analysis is based on a nested logit model that was developed to integrate intrahousehold interactions with tour-based mode choices; Sydney Household Travel Survey data are used. The results show that joint household travel accounts for more than half of weekday home-based tours in Sydney, Australia. The arrangement of joint household tours is shown to depend on household context, situational factors, and social constraints. Mode choice associated with different joint tour patterns is influenced by household and individual characteristics, tour attributes, and transport-related fringe benefits.
Mixed Multinomial Logit Model for Out-of-Home Leisure Activity Choice
Authors: Grigolon Anna B. , Kemperman Astrid D. A. M. , Timmermans Harry J. P.
Published: September 2013

The design and the results of a study of the factors that influence the choice of out-of-home leisure activities are presented. Influencing factors appear to be related to sociodemographic characteristics, personal preferences, characteristics of the built environment, and other aspects of the activities themselves, such as transport mode and day of the week. The Dutch continuous time–use research data on leisure activities for 2008 to 2009 were used for estimating a mixed multinomial logit model that accounts for heterogeneity in individuals’ preferences. The model formulation also allows analysis of substitution and complementarity between the types of activities. Results indicate differences in behavior between people with different sociodemographic characteristics, especially regarding the life-cycle stage, which is a variable composed by age and household composition. The built environment exerts a slight influence on the choice of leisure activity purpose, whereas travel party has a strong influence. For substitution and complementary relationships between activity purposes, although outdoor leisure decreases the propensity to perform sports or hobbies–courses activities, such leisure increases the propensity to perform fun shopping and going-out or cultural activities. Limitations of the study are discussed.
On the Value of Business Travel Time Savings
Authors: Kato Hironori
Published: September 2013

Theoretical models of the value of travel time savings (VTTS) in business are analyzed. The Hensher formula is derived on the basis of these models. Previous research on business VTTS, including the wage-rate-plus approach and the Hensher approach, is reviewed. Five issues are identified with respect to business VTTS: the business travel decision maker, the player who is willing to pay to save travel time, productivity while traveling, patterns of business travel schedules, and wage payment for working overtime. Four time allocation models are formulated, and the business VTTS is derived for each one. The models are based on group utility maximization according to the combined viewpoints of an employer and an employee. Both zero productivity and positive marginal productivity while traveling are considered. In addition, two patterns of travel schedule are examined: business travel within work hours and business travel outside work hours. The Hensher approach is derived theoretically from the group utility maximization approach. The derivation shows that business VTTS depends on two assumptions: the balanced weight of the utility functions between the employer and the employee and the allocation of saved business travel time to leisure time in proportion to the ratio of business travel time that occurs within leisure time to total business travel time. The implications of the Hensher formula are discussed.
Adjustment of Origin–Destination Matrices Based on Traffic Counts and Bootstrapping Confidence Intervals
Authors: Benitez F. G. , Romero L. , Caceres N. , del Castillo J. M.
Published: September 2013

Mobility studies require, as a preliminary step, that a survey of a sample of users of the transportation system be conducted. The statistical reliability of the data determines the goodness of the results and the conclusions that can be inferred from the analyses and models generated. Because of the high costs of collection, data are partially reused in either a disaggregated or an aggregated manner. In the first case, statistical reliability is not always guaranteed; this condition affects the results that will be derived from projections and estimates of future hypothetical scenarios. A methodology is presented: it is based on bootstrapping techniques and is used for robust statistical estimation of mobility matrices. Confidence intervals of travel between origin–destination pairs defined by each matrix cell derived from a survey are generated. The result is applicable to defining the dimensions of certainty for matrix cells and subsequent adjustment by techniques based on aggregate data (e.g., traffic counts, cordon line matrices, paths). A statistically reliable data mobility study conducted in Spain at a regional level is used. Results derived from disaggregating data at an interprovincial level are presented, along with an application to the posterior mobility matrix adjustment based on traffic count data. The study results demonstrate the potential of the methodology developed and the usefulness of the conclusions.
Day-to-Day Origin–Destination Tuple Estimation and Prediction with Hierarchical Bayesian Networks Using Multiple Data Sources
Authors: Ma Yinyi , Kuik Roelof , van Zuylen Henk J.
Published: September 2013

Prediction of traffic demand is essential, either for an understanding of the future traffic state or so necessary measures can be taken to alleviate congestion. Usually, an origin–destination (O-D) matrix is used to represent traffic demand between two zones in transportation planning. Vehicles are assumed to be homogeneous; the trips of each vehicle are examined separately. This traditional O-D matrix lacks a behavioral basis and trip-based model structure. Another research stream of travel activity–based research addresses individual travel behaviors. This stream addresses the trip chain for travelers, but the research scope is attributes of trips, which ignores the road network. The concept of the O-D tuple, a sequence of dependent O-D pairs, is proposed for linking these two fields and for predicting traffic demand better. Through advanced monitoring systems that identify and track vehicles in the road network, the additional uncertainties of O-D tuples can be mitigated and thus reduce the underspecification more specifically. The hierarchical Bayesian networks mechanism in Gaussian space with multiprocesses is proposed for gaining the posterior of uncertain parameters. The model includes level and trend components for predicting future traffic volumes. A case study demonstrates that the proposed method can predict demand, and the path flow from cameras can reduce uncertainty in the estimation and prediction process, especially for O-D tuples.
Estimating Nested Logit Models with Censored Data
Authors: Newman Jeffrey P. , Ferguson Mark E. , Garrow Laurie A.
Published: September 2013

The presented methodology estimates parameters of a nested logit model when decision makers who choose one of the alternatives are systematically excluded from the sample data that are used to estimate the model (i.e., censored). Unlike existing methods for estimating discrete choice model parameters with censored data, which require exogenous information beyond the specification of the model to be estimated and the available sampled observations, the proposed method requires no additional outside information. It is demonstrated empirically that this approach can recover not only generic model parameters that apply to common attributes of all alternatives but also parameters for alternative-specific constants and variables associated with both observed and censored alternatives. Although the standard errors of the estimated parameters are larger than those of models estimated with uncensored data, censored data methods still hold great potential for applications in which uncensored data are expensive or impossible to collect.
Spatial Transferability of Person-Level Daily Activity Generation and Time Use Models
Authors: Sikder Sujan , Pinjari Abdul Rawoof
Published: September 2013

An empirical assessment is made of the spatial transferability of person-level daily activity generation and time use models in regions in Florida and between Florida and California. The empirical models are for unemployed adults and are based on the multiple discrete-continuous extreme value structure. The prediction properties of the model are examined first. The results shed new light on the prediction properties of the multiple discrete-continuous extreme value model that have implications for transferability and that provide insight into how the model structure could be improved. Two approaches to transferring models are evaluated—naïve transfer and updating model constants—with measures such as log likelihood–based metrics, aggregate predictive ability, and model sensitivity to changes in demographic characteristics. Results suggest that accurate prediction of aggregate observed patterns is not an adequate yardstick with which to assess transferability; emphasis should be placed on model sensitivity to changes in explanatory variables. Updating of constants improves a transferred model's aggregate prediction ability, but not necessarily its policy sensitivity. The extent of transferability between regions within a state is greater than that across states. Within Florida, there is greater transferability between urban regions (especially between Southeast Florida and Central Florida) than between urban and rural regions.
Toll Pricing
Authors: Jiang Lan , Mahmassani Hani S.
Published: September 2013

Because of the increasing interest in implementation and exploration of a wider range of pricing alternatives, a study was done to compare approaches for capturing the heterogeneity of user preferences in forecasting the demand for tolled facilities resulting from user responses to pricing schemes. Existing tools used in practice typically deal with users’ value of time (VOT) heterogeneity in one of two ways: (a) ignore VOT and use a constant value of time and (b) recognize VOT by defining discrete user classes, each corresponding to a given VOT range, represented by its midpoint or average VOT. The first approach is fundamentally incorrect and would lead to highly biased estimates of network performance; the second is only a coarse approximation. A third approach, which recognizes that VOT is a continuous variable that is distributed probabilistically across the user population, is gaining greater attention. The following questions are examined: (a) What are the impacts of different VOT assumptions on prediction biases in forecasts of toll road usage under different pricing schemes? (b) Do the discrete treatments provide a good approximation of models with continuously distributed VOT, and if so how should VOT be assigned to user classes? (c) What are the relative computational implications of different VOT assumptions, and what is the role of efficient implementation techniques for large-scale network applications? The results suggest that recognizing the continuous nature of the VOT distribution is justified both with regard to accuracy and on computational grounds, especially in light of recent algorithmic and implementation advances.
Real-Time Detection and Tracking of Traffic Shock Waves by Conjugated Low-Angle Cameras
Authors: Yang Deliang , Chen Yangzhou , Xin Le
Published: September 2013

This paper proposes a method to detect and to track in real time three traffic shock waves (i.e., queuing, discharge, and departure) that appear in a section at a signalized intersection. Detection and tracking of the shock waves are accomplished by conjugated low-angle cameras, one of which is installed in front of the stop line and the other at a proper place behind the stop line. The cameras jointly monitor the regions of interest in the section with opposite and long-range views. On the basis of the weighted least squares method, the video data captured by the conjugated cameras are fused at the pixel level. Then the fused images are adapted to track the queuing and discharge shock waves in real time by a duplex, flexible window algorithm. Simultaneously, the Haar feature–based AdaBoost cascade classifiers are adopted to identify the vehicle tails and heads and to adjust the tracking results in the flexible window. To track the departure shock wave in real time, the discharge speed of vehicles is obtained through the combined tracking of sparse feature points of the vehicles in the regions of interest of the conjugated cameras. Experimental results show that the proposed method can track the traffic shock waves accurately in real time under changed light conditions during evening rush hour. The tracking results of the shock waves can be further applied to obtain various traffic parameters (e.g., queue length, stop delay, discharge time).
Traffic Management Effects of Variable Speed Limit System on a German Autobahn
Authors: Weikl Simone , Bogenberger Klaus , Bertini Robert L.
Published: September 2013

An empirical study of the traffic flow effects of a variable speed limit (VSL) system on a three-lane German autobahn is presented. The study integrated loop detector data and VSL and driver information provided by overhead dynamic message signs along a 16.3-km section of Autobahn A99 near Munich, Germany. Unlike most VSL deployments, the data sources allowed for a with-and-without analysis to reflect traffic flow and driver behavior in the presence and in the absence of the VSL system. In addition to speed, the primary features of interest were the spatial–temporal extent of the queue (congestion), flow changes caused by identified bottlenecks, the distribution of flow across lanes, the percentage of trucks per lane, and the flow homogeneity between lanes. The analysis recorded bottleneck flow reductions that were balanced across all lanes with an active VSL system. With an inactive VSL system, the flow reductions were slightly lower and occurred primarily in the center and shoulder lanes; there was a small flow increase in the median lane. Further examination indicated that the gain in homogeneity and safety with the system in place was at the cost of capacity. Possible reasons that might explain the differences between the scenarios with and without the VSL system had their basis in the ban against passing by trucks, which was in effect when the driver information system was active.
Assessment of Dynamic Speed Limits on Freeway A20 near Rotterdam, Netherlands
Authors: Hoogendoorn S. P. , Daamen W. , Hoogendoorn R. G. , Goemans J. W.
Published: September 2013

On Freeway A20 near Rotterdam, Netherlands, a trial with dynamic speed limits began on June 28, 2011. On a 4.2-km stretch, the speed limit increased from 80 to 100 km/h as soon as congestion appeared to set in and at night. The aim of dynamic speed limits was to improve traffic operations and to avoid deterioration in the local air quality. This paper presents an assessment of this trial with respect to traffic operations, air quality, noise level, and traffic safety. Traffic operations on A20 appeared to have improved significantly as a consequence of the dynamic speed limits, which produced a reduction in the number of lost vehicle hours by 600 (20%). This improvement was the result of a 4% increase in the free-flow capacity at the main bottleneck on the freeway stretch. The dynamic speed limits caused a change in driver behavior: the median lane was better occupied when flow increased. Air quality deteriorated slightly. The effects varied along the stretch with a maximum increase in nitrogen oxides and particulate matter10 emissions of 3.7% and 3.6%, respectively. However, the effects on the average concentration of nitrogen oxides per year were limited. The noise level appeared to increase slightly with 0.2 dB. This increase occurred mainly during the two peak periods. The indicators for traffic safety showed sometimes a (possibly) positive and sometimes a (possibly) negative effect. However, it was not likely that dynamic speed limits had a significant negative effect on traffic safety.
Improving Accuracy and Precision of Travel Time Samples Collected at Signalized Arterial Roads with Bluetooth Sensors
Authors: Saeedi Amirali , Park SeJoon , Kim David S. , Porter J. David
Published: September 2013

Time-stamped, media access control addresses, acquired from Bluetooth-enabled devices to collect travel time data, have received significant attention in the past few years. Research has focused mainly on the application of Bluetooth technology to obtain travel time data on freely flowing roads. A few studies have addressed the use of Bluetooth data collection systems on arterial roads, particularly with respect to travel times between signalized intersections, with questionable accuracy. The objective of this research was to develop a methodology to collect accurate and precise travel time data between signalized intersections, with the use of a data collection system that had a Bluetooth basis. The developed methodology utilized received signal strength indicator (RSSI) data to improve signifi-cantly the accuracy of intersection-to-intersection travel time samples. Test results on a busy arterial road showed that the travel time samples generated with the RSSI method were significantly better (i.e., had less error) than the travel time samples calculated with other methods reported in the literature. The proposed RSSI travel time data collection method could be implemented with any wireless technology that provided a unique identification number to distinguish between different mobile devices and an associated signal strength measurement during the wireless communication process.
U.S. Integrated Transportation Systems in the Future, 2030 to 2050
Authors: Shaheen Susan A. , Camel Madonna L. , Lee Kunik
Published: September 2013

Intelligent transportation systems (ITS) have focused primarily on systems management. To improve connectivity and safety further, ITS might embrace a more holistic planning approach. Although the future of ITS remains an open question, ITS evolution is closely linked to the social, political, economic, legal, and environmental dimensions. This paper presents the results from four expert workshops: (a) initial steering committee workshop (February 2011), (b) two expert scenario-planning workshops (June 2011), and (c) a final steering committee workshop (July 2011). The scenario planning workshops explored the implications of alternative futures in ITS and incorporated a broad, interdisciplinary approach to develop a long-term transportation vision (2030 to 2050 time horizon) for the United States. Twenty-four experts, who represented diverse disciplines, participated in a series of workshops to envision plausible futures and to assess their effects on the transportation system. By exploring different futures, experts identified opportunities and barriers to the implementation of advanced, seamless transportation systems. Opportunities included the deployment of adaptable, integrated technology and transportation infrastructure to address natural disasters and climate change. The most significant barriers were funding and politics. The experts suggested that financial barriers could be overcome through the use of innovative funding techniques and improved public outreach. Several visions for an integrated ITS approach were then built on the experts' recommendations to address social and environmental challenges in the future. These recommendations included private–public partnerships, distributed implementation models (e.g., localized), and the development of seamless transportation systems to reduce energy consumption, emissions, and road congestion.
Modulating the Human Gut Microbiome as an Emerging Therapeutic Paradigm
Authors: Rajpal Deepak K. , Brown James R.
Published: September 2013

The human body is actually a vast and changing ecosystem comprised of billions of microbial organisms, known collectively as the microbiome. Within the last few years, the study of the microbiome and its impact on human health has been a rapidly growing area of biomedical science. The gut intestinal tract microbiome has been a particular focus of research given its potential role in many inflammatory and metabolic diseases as well as drug metabolism. Although a nascent field, the potential for modulating the gut microbiome or human host interactions associated with these microbes offers new therapeutic strategies for many chronic diseases, in particular obesity, diabetes and inflammatory bowel diseases. Here we provide an overview of present knowledge about the gut microbiome, its putative role in metabolic diseases and the potential for microbiome focused treatments from the drug development perspective.
The Link between Copper and Wilson's Disease
Authors: Purchase Rupert
Published: September 2013

Wilson's disease (hepatolenticular degeneration) is a rare inherited autosomal recessive disorder of copper metabolism leading to copper accumulation in the liver and extrahepatic organs such as the brain and cornea. Patients may present with combinations of hepatic, neurological and psychiatric symptoms. Copper is the therapeutic target for the treatment of Wilson's disease. But how did copper come to be linked with Wilson's disease? The answer encompasses a study of enzootic neonatal ataxia in lambs in the 1930s, the copper-chelating properties of British Anti-Lewisite, and the chemical analysis for copper of the organs of deceased Wilson's disease patients in the mid-to-late 1940s. Wilson's disease is one of a number of copper-related disorders where loss of copper homeostasis as a result of genetic, nutritional or environmental factors affects human health.
Isotopes and Analogs of Hydrogen – from Fundamental Investigations to Practical Applications
Authors: Macrae Roderick M.
Published: September 2013

Hydrogen has a central role in the story of the universe itself, and also in the story of our efforts to understand it. This paper retells the story of the part played by hydrogen and its stable isotope deuterium in the primordial synthesis of the elements, then goes on to describe how the spectrum of atomic hydrogen led to insights into the laws governing matter at the most fundamental level, from the quantum mechanics of Schrödinger and Heisenberg, through quantum electrodynamics, to the most recent work investigating the underlying structure of the proton itself. Atomic hydrogen is unique among the elements in that the concept of isotopy – atoms having the same nuclear charge but different masses – is stretched to its limit in the isotopes of hydrogen, ranging from the well-known isotopes deuterium and tritium to exotic species such as muonium, muonic helium, and positronium. These atoms, or atom-like objects, have much to tell us about fundamental aspects of the universe. In recent years the idea of utilizing hydrogen either as an energy source (through nuclear fusion) or as an energy storage medium (bound in hydrides or other materials) has attracted much attention as a possible avenue to a post-oil energy future. Some of the more interesting recent developments are described here.
Proceso simbólico y transmisión musical : el romance y los cantos festivos religiosos del sur de Colombia
Authors: Friedmann Susana
Published: September 2013

Resumen. — En las tierras bajas de Colombia, los romances espirituales incorporados en los cantos festivos de las poblaciones negras siempre se han asociado con el canto gregoriano o con el cante jondo, pero nunca se ha advertido la compatibilidad entre los sistemas musicales europeos y africanos, ni entre ciertas modalidades de la tradición oral y otros aspectos compartidos por las dos culturas. En el proceso de transculturación, se han conjugado criterios de selectividad que han favorecido la retención de rasgos afines que, por la misma operación metafórica implícita en toda communicación musical, han pasado inapercibidos y han sido interpretados inadecuadamente.
Panorama de la lírica popular mexicana
Authors: Díaz Roig Mercedes
Published: September 2013

Résumé. — La chanson populaire, expression du peuple mexicain, est variée et présente une certaine amplitude stylistique. Elle comprend deux types : la chanson « populaire », produit d'une mode temporelle, et la chanson traditionnelle. Cette dernière est l'objet de cette étude.

Sa diffusion est régionale, sauf en ce qui concerne les chansons d'enfants et quelques chansons de circonstance. Mais les strophes (copias) n'ont pas cette limitation géographique, elles circulent librement d'une chanson à l'autre. Cela est possible grâce à l'abondance de formes-base (quatrain, seguidille), du vers octosyllabe (87 %) et à la capacité des chanteurs pour l'adaptation formelle. Le corpus est riche et, en plus, chaque copia peut être variée produisant ainsi des versions multiples. Dans cette vaste gamme, on peut repérer des traits caractéristiques propres au pays : dans la forme, l'abondance relative de la sextille et la fréquence de la rime consonantique. Les différences les plus fortes sont lexicales. Dans la thématique, on remarque les copias sur les animaux, le « machismo » et les copias humoristiques où se révèle la picaresque mexicaine.