bluuebunny/crossref_metadata_2025 huggingface dataset:
Propensity score models in observational comparative effectiveness studies: cornerstone of design or statistical afterthought?
Authors: Robinson John W
Published: March 2012

Propensity score models are increasingly used in observational comparative effectiveness studies to reduce confounding by covariates that are associated with both a study outcome and treatment choice. Any such potentially confounding covariate will bias estimation of the effect of treatment on the outcome, unless the distribution of that covariate is well-balanced between treatment and control groups. Constructing a subsample of treated and control subjects who are matched on estimated propensity scores is a means of achieving such balance for covariates that are included in the propensity score model. If, during study design, investigators assemble a comprehensive inventory of known and suspected potentially confounding covariates, examination of how well this inventory is covered by the chosen dataset yields an assessment of the extent of bias reduction that is possible by matching on estimated propensity scores. These considerations are explored by examining the designs of three recently published comparative effectiveness studies.
Comparative effectiveness of different angiotensin-converting enzyme inhibitors on the risk of hospitalization in patients with heart failure
Authors: Chitnis Abhishek S , Aparasu Rajender R , Chen Hua , Johnson Michael L
Published: March 2012

Aims:
Existing randomized controlled trials do not address the comparative effectiveness of different angiotensin-converting enzyme inhibitors (ACEIs) on hospitalization due to heart failure (HF)-hospitalization in patients with HF. We sought to examine the effect of four ACEIs on HF-hospitalization in a large real-world HF population.
Methods:
The study was a retrospective analysis of a national cohort of patients with HF identified from the Department of Veterans Affairs (TX, USA). A multiple propensity score analysis was used to balance 47 baseline patient characteristics between the different ACEIs. The effect of different ACEIs on time to HF-hospitalization was assessed using the multiple propensity score-weighted multivariable Cox proportional hazard model.
Results:
The study included 139,994 patients with 69.50% (97,293) on lisinopril, 21.79% (30,503) on fosinopril, 8.41% (11,775) on captopril and 0.30% (423) on enalapril. Propensity scores balanced nearly all differences between different ACEIs groups. Enalapril (hazard ratio [HR]: 0.800; 95% CI: 0.492–1.297), fosinopril (HR: 0.971; 95% CI: 0.877–1.074), and lisinopril (HR: 1.005; 95% CI: 0.918–1.101) when compared with captopril were found to have similar effectiveness in reducing HF-hospitalizations.
Conclusion:
In patients with HF, we found that the four ACEIs are equally effective in reducing HF-hospitalization in day-to-day practice.
Stakeholder participation in comparative effectiveness research: defining a framework for effective engagement
Authors: Deverka Patricia A , Lavallee Danielle C , Desai Priyanka J , Esmail Laura C , Ramsey Scott D , Veenstra David L , Tunis Sean R
Published: March 2012

Aims:Stakeholder engagement is fundamental to comparative effectiveness research (CER), but lacks consistent terminology. This paper aims to define stakeholder engagement and present a conceptual model for involving stakeholders in CER.Materials & methods:The definitions and model were developed from a literature search, expert input and experience with the Center for Comparative Effectiveness Research in Cancer Genomics, a proof-of-concept platform for stakeholder involvement in priority setting and CER study design.Results:Definitions for stakeholder and stakeholder engagement reflect the target constituencies and their role in CER. The ‘analytic-deliberative’ conceptual model for stakeholder engagement illustrates the inputs, methods and outputs relevant to CER. The model differentiates methods at each stage of the project; depicts the relationship between components; and identifies outcome measures for evaluation of the process.Conclusion:While the definitions and model require testing before being broadly adopted, they are an important foundational step and will be useful for investigators, funders and stakeholder groups interested in contributing to CER.
Investor Sentiment and Stock Market Response to Earnings News
Authors: Mian G. Mujtaba , Sankaraguruswamy Srinivasan
Published: March 2012

We examine whether market-wide investor sentiment influences the stock price sensitivity to firm-specific earnings news. Using the recently developed measure of investor sentiment by Baker and Wurgler (2006), we find that the stock price sensitivity to good earnings news is higher during high sentiment periods than during periods of low sentiment, whereas the stock price sensitivity to bad earnings news is higher during periods of low sentiment than during periods of high sentiment. This influence of sentiment is especially pronounced for the earnings news of small stocks, young stocks, high volatility stocks, non-dividend-paying stocks, and stocks with extremely high and low market-to-book ratios. Further analysis suggests that the sentiment-driven mispricing of earnings contributes to the general mispricing of stocks due to investor sentiment.

JEL Classifications: D14; D21; G24.
Chief Audit Executives' Evaluations of Whistle-Blowing Allegations
Authors: Guthrie Cynthia P. , Norman Carolyn Strand , Rose Jacob M.
Published: March 2012

This study examines the effects of the source of whistle-blowing allegations and potential for allegations to trigger concerns about reputation threats on chief audit executives' handling of whistle-blowing allegations. The participants for this study, chief audit executives (CAEs) and deputy CAEs, evaluated whistle-blowing reports related to financial reporting malfeasance that were received from either an anonymous or a non-anonymous source. The whistle-blowing reports alleged that the wrongdoing resulted from either the exploitation of substantial weaknesses in internal controls (suggesting higher responsibility of the CAE and internal audit) or the circumvention of internal controls (suggesting lower responsibility of the CAE or internal audit). Findings indicate that CAEs believe anonymous whistle-blowing reports to be significantly less credible than non-anonymous reports. Although CAEs assessed lower credibility ratings for the reports alleging wrongdoing by the exploitation of substantial weaknesses in internal controls, they allocated more resources to investigating these allegations.
On finite retract lattices of monounary algebras
Authors: Jakubíková-Studenovská Danica , Pócs Jozef
Published: February 2012

For a monounary algebra (A, f) we denote R
∅(A, f) the system of all retracts (together with the empty set) of (A, f) ordered by inclusion. This system forms a lattice. We prove that if (A, f) is a connected monounary algebra and R
∅(A, f) is finite, then this lattice contains no diamond. Next distributivity of R
∅(A, f) is studied. We find a representation of a certain class of finite distributive lattices as retract lattices of monounary algebras.
Non-constant periodic solutions for second order Hamiltonian system with a p-Laplacian
Authors: Zhang Xingyong , Tang Xianhua
Published: February 2012

In this paper, some existence theorems are obtained for nonconstant periodic solutions of second order Hamiltonian system with a p-Laplacian by using the Linking Theorem.
The Middle Triassic marine reptile biodiversity in the Germanic Basin, in the centre of the Pangaean world
Authors: Diedrich Cajus
Published: February 2012

The Middle Triassic fossil reptile localities near Bayreuth (Bavaria, southern Germany) consist of shallow marine autochthonous glauconitic marls and terebratulid-rich tempestite carbonates of the newly defined Bindlach and Hegnabrunn formations. Single bones and incomplete skeletons of marine reptiles have been recorded in bone beds within in the Illyrian and Fassanian stages. These include the remains of the sauropterygians Neusticosaurus sp., Lariosaurus cf. buzzii [1], Nothosaurus mirabilis [2], Paranothosaurus giganteus [2], Placodus gigas [3], Cyamodus rostratus [4], Cyamodus münsteri [5], Pistosaurus longaevus [6], and ichthyosaursOmphalosaurus sp., and Shastasaurus sp. or proterosaur Tanystrophaeus conspicuus [7]. New skeletal reconstructions are based on the osteological analysis of three dimensionally preserved bones and skeletal remains. The large number of marine endemic placodont macroalgae feeders (P. gigas) in the Bayreuth sites coincides with the presence of invertebrate palaeocommunities that are characteristic of macroalgae meadow paleoenvironments. Most of the reptile species and genera from the Bayreuth localities also occur in beds of similar ages from the Monte San Giorgio (Switzerland/Italy) or Perledo (Italy) lagoonal areas. Ichthyosaurs and pistosaurs were adapted for open marine conditions, and may have migrated from the Panthalassa Oceans into the shallow marine Germanic Basin to reproduce, whereas placodonts and many other sauropterygians seem to have lived permanently in those shallow marine habitats, with large squamates and thecodont or smaller archosaurs in coastal areas.
The effects of intensive rainfalls (flash floods) on the development on the landforms in the Kőszeg Mountains (Hungary)
Authors: Veress Márton , Németh István , Schläffer Roland
Published: February 2012

The effects of the intensive rainfall episodes in the years 2009 and 2010 in the Kőszeg Mountains were investigated. Channel profiles were constructed at various times during these periods, which were used to describe the channel changes. We measured the length of the incised and filled sections on multiple occasions. We could establish the degree and the direction of the changes using this data. The sediment veneer that developed in the area of Kőszeg town was mapped and its conditions of development were examined. The erosion and accumulation landforms developed during these years were classified and described. These forms are the following: rills, gullies, alluvial fans and sediment veneer. We distinguished and characterised those which had previously formed, but they were changed or increased (the channels). We established the conditions under which the sediment veneer can develop, furthermore those conditions which can increase the chance of the formation of this landform. These conditions are the following: the high density of roads in the catchment areas of valleys leading to settlements, the great thickness of superficial deposit, and the steep slope of the surface of the catchment area. We created theoretical classification of the morphological environment where the development of sediment veneer may happen and identified settlements with structures which promote or prevent the development of the sediment veneer. We determined the probability of the development of the sediment veneer at some settlements in Kőszeg, and suggestions have been given to decrease the chance of the development of this sediment veneer.
Penile fracture caused by wild bear attack
Authors: Agarwal A , KC SR , Shrestha P , Hirachan S , Belokar WK
Published: March 2012

Interaction between humans and wild animals has increased in recent times because of overlap of habitats. A proportion of this interaction is violent. Usually a large wild animal, like bear, causes significant bony trauma or attacks upper torso of body. We herein present a case of Asiatic black bear attack on an unusual part of body in a 40-year-old man near Nawalparasi, Nepal. The beast attacked genital region causing penile fracture. Patient was managed successfully in three stages. DOI: http://dx.doi.org/10.3126/jcmsn.v7i1.5973 JCMSN 2011; 7(1): 47-51
Heuristic Algorithm for Priority Traffic Signal Control
Authors: He Qing , Head K. Larry , Ding Jun
Published: February 2012

A heuristic algorithm is presented for traffic signal control with simultaneous multiple priority requests at isolated intersections in the context of vehicle-to-infrastructure communications being available on priority vehicles, such as emergency vehicles and transit buses. This heuristic algorithm can achieve near-optimal signal timing when all simultaneous requests are considered and can be visualized in a phase–time diagram. First, the problem with the control of multiple priority traffic signals is transformed into a network cut problem that is polynomial solvable under some reasonable assumptions. Second, a phase–time diagram is presented to visualize and evaluate priority delay given a signal plan and a collection of priority request arrival times. Microscopic traffic simulation is used to compare the heuristic with the state-of-the-practice algorithms for transit signal priority. The proposed heuristic algorithm could reduce average bus delay in congested conditions by about 50%, especially with a high frequency of conflicting priority requests.
Visual Education Tools to Illustrate Coordinated System Operation
Authors: Brennan Thomas M. , Day Christopher M. , Sturdevant James R. , Bullock Darcy M.
Published: February 2012

The configuration of a single controller in a coordinated arterial signal system requires the programming of approximately 250 parameters ranging from minimum green times to complex hardware-specific settings that determine how unused green time is allocated to competing phases. When this parameter count is extrapolated to a 10-intersection arterial (2,500 parameters), one or more data entry errors are likely to occur and must be identified and corrected. Ensuring that the resulting coordinated signal system operates as designed requires an exceptionally high level of expertise to confirm by visual field observations and a perhaps unattainable level of expertise in verification by inspection of data entry screens in an office. There is a clear need for visualization tools to provide educational insight into how coordinated signal systems should be expected to operate under different parameter settings and to document coordinated system behavior. In this paper a series of graphics was developed to visualize coordinated system operation characteristics such as time-of-day schedule change time, observed cycle length, green time and split time, coordinated phase actuation, early return to green, arrivals over advance detection relative to green indication, progression quality characteristics related to offset, adjacent signal synchronization, coordinated phase operation in rest, plan time changes, preemption, impact of queuing, and longitudinal analysis of splits. These graphics can be used as a new learning tool, as well as a visual feedback tool to confirm that a coordinated system is operating as expected.
Modeling Variability of Urban Travel Times by Analyzing Delay Distribution for Multiple Signalized Intersections
Authors: Zheng Fangfang , Van Zuylen Henk
Published: February 2012

It is widely accepted that travel times in urban road networks can vary greatly within a short period as well as from period to period in a single day. One important cause for this variability in urban travel times is the delay that drivers experience at intersections, particularly signalized intersections. This delay can be due to the time a driver needs to wait for a red light or the time needed for a queue of waiting vehicles at an intersection to dissolve, or both. As a result, the ability to capture the characteristics of delay at signalized intersections is a critical, yet challenging, step in estimating and predicting urban link travel times. The uncertainties in these experienced delays are caused by traffic conditions and traffic control at the intersections. In this paper a delay distribution model is developed for an urban trip over a route with two consecutive fixed-time controlled intersections. The proposed model captures the stochasticity in the arrival and departure process at the first intersection. An example illustrates how these stochastic factors influence the realized delay distribution for the two consecutive signalized intersections. Delay distributions are analyzed for different levels of mismatch of the two controlled intersections (from well coordinated to badly coordinated) under different degrees of saturation. Finally, the predicted delay distributions are validated with the VISSIM simulation model and show that the proposed (analytical) model can represent the VISSIM simulation data.
Intelligent Traffic Signal System for Isolated Intersections
Authors: Lu George X. , Zhang Yi , Noyce David A.
Published: February 2012

One critical issue of traffic control is the optimization of signalized intersections for improved multimodal safety and operations. Accommodating pedestrian traffic at intersections is challenging because the demands of multimodal service compete fiercely on limited green time resources. The Highway Capacity Manual prescribes that the parallel vehicle green must exceed “Walk” plus pedestrian clearance interval (PCI) timed by a design walking speed. This static PCI timing is unsafe because seniors and children are likely to be slower than the design pedestrian. Furthermore, a vehicle-flow issue arises when the prolonged PCI exceeds the operationally efficient parallel green: additional vehicle right-of-way, unnecessary for operational efficiency, preempts green time from conflicting phase(s) and increases intersectionwide queuing delays. Queuing delays necessitate a trade-off between competing multifaceted traveler needs. Fuzzy logic control (FLC) proves effective, flexible, and robust in handling competing objectives. With the dynamic PCI concept, this research developed an intelligent traffic signal system that performed friendly pedestrian accommodation and also incorporated FLC into fulfilling multifaceted vehicle needs. The potential benefits from the new system optimized with a genetic algorithm were quantified through a comparison with a standard dual-ring, eight-phase, vehicle-actuated controller, conventionally cited as NEMA (National Electrical Manufacturers Association) control. Microsimulation experiments revealed that the current countermeasure, which lowered PCI timing design speed to strengthen crossing safety, was operationally deficient. The existing timing standard cannot offer adequate safety for all pedestrians, and the NEMA system omits multifaceted vehicle needs in control logic. In contrast, the FLC system fully protects all pedestrians through dynamic PCI and smartly serves manifold vehicle needs well. The FLC system outperforms the NEMA control by embodying a reasonable trade-off between competing objectives in the management of an isolated intersection.
Hierarchical Network Model of Safe High-Speed Rail Operation
Authors: Wang Yanhui , Xiao Xuemei , Jia Limin , Zhang Chenchen
Published: March 2012

This paper presents a preliminary hierarchical network model based on an analysis of the interaction of relationships between operating safety factors of high-speed rail (HSR). The model is based on the characteristics and factors specific to HSR operation and aims to provide a new theory and method for assessing the safety of HSR operation with the use of the relationship analysis methods of a hierarchical network model. A comprehensive theory of safety assessment in HSR operations is necessary for HSR designers and operators to consider rail safety pro-actively rather than passively. The development and the application of such a broad-ranging safety assessment theory for HSR operation could help to guarantee efficient HSR operation by protecting the safety of passengers, reducing losses, maintaining social stability, and improving economic efficiency.
Integrated Optimization Model to Manage Risk of Transporting Hazardous Materials on Railroad Networks
Authors: Lai Yung-Cheng , Kawprasert Athaphon , Lin Chen-Yu , Saat M. Rapik , Liang Chun-Hao , Barkan Christopher P. L.
Published: March 2012

Rail transport plays a key role in safely and economically moving hazardous materials from production to consumption points. As a result of heightened safety and security concerns, interest in all possible means of reducing the risk of transporting hazardous materials has intensified in recent years. Various approaches to railroad accident prevention— including infrastructure improvements, packaging enhancements, operational changes, and alteration of the route structure—are available. Operations research techniques have been applied to consider each approach individually, but no technique has integrated the approaches into a single model. This study introduced an integrated mathematical model to formally consider a combination of approaches to reduce risk. The framework enabled simultaneous consideration of route choices, tank car safety designs, and track maintenance to determine an optimal strategy that minimized risk and costs. Model formulation was provided in the form of nonlinear and mixed-integer programming. For illustration, a small-scale, hypothetical network flow of a hazardous material was considered. Numerical results showed that the optimal strategy could substantially reduce risk with a marginal increase in costs. The integrated model provided a framework for choosing the most effective risk-mitigation strategy for a particular rail network given various constraints. It could be applied to multiple types of commodities and adapted to address various questions for local, regional, or systemwide planning and decision making to provide the safest transportation possible given constrained resources. The framework would be particularly beneficial to rail carriers interested in how to best allocate safety and engineering resources to maximize safety.
Noncontact Ultrasonic Guided-Wave System for Rail Inspection
Authors: Coccia Stefano , Phillips Robert , Bartoli Ivan , Salamone Salvatore , Di Scalea Francesco Lanza , Fateh Mahmood , Carr Gary
Published: March 2012

The University of California, San Diego (UCSD), with an FRA Office of Research and Development grant, is developing a system for high-speed and noncontact rail defect detection. A prototype was designed and field tested with the support of Volpe National Transportation Systems Center and ENSCO, Inc. The goal of this project was to develop a rail defect detection system that provided (a) better defect detection reliability (including internal transverse head defects under shelling and vertical split heads) and (b) higher inspection speed than achievable by current rail inspection systems. This effort was also in direct response to safety recommendations issued by the National Transportation Safety Board after the disastrous train derailments at Superior, Wisconsin, in 1992 and Oneida, New York, in 2007, among others. The UCSD prototype used noncontact ultrasonic probing of the rail head (laser and air-coupled sensors), ultrasonic guided waves, and a proprietary real-time statistical analysis algorithm that maximized the sensitivity to defects while it minimized false positives. The design allowed potential inspection speeds up to 40 mph, although to date all field tests were conducted up to 15 mph. This paper (a) summarizes the latest technology development test conducted at the rail defect farm of Herzog, Inc., in Saint Joseph, Missouri, in June 2010 and (b) describes the completion of the new rail defect farm facility at the UCSD Camp Elliott Field Station with partial in-kind donations from the Burlington Northern Santa Fe Railway.
Analysis of Derailments by Accident Cause
Authors: Liu Xiang , Barkan Christopher P. L. , Saat M. Rapik
Published: March 2012

The risk of train derailment associated with rail transportation is an ongoing concern for the rail industry, government, and the public. Various approaches have been considered or adopted to analyze, manage, and reduce risk. Upgrading track quality has been identified as one possible strategy for preventing derailment. The quality of freight railroad track is commonly divided into five principal classes by FRA on the basis of track structure, track geometry, and inspection frequency and method. The higher the track class, the more stringent are the track safety standards and thus a higher maximum train speed is allowed. Upgrading track class is likely to prevent certain track-related derailments; however, this upgrade may also increase the risk of certain types of equipment failure that are more likely to occur at higher speeds. Consequently, more sophisticated approaches need to be developed to examine the interactions among accident causes that may be differently affected by upgrades to track infrastructure. This paper analyzes several critical parameters for predicting train derailment risk by using derailment statistics from the FRA accident database and related literature. A general method was developed to assess derailment risk by accident cause and FRA track class. The safety benefits of track class upgrade in reducing the risks from certain accident causes were quantitatively evaluated. The model can be extended by incorporating additional risk factors to more accurately assess the effectiveness of various derailment prevention efforts for reducing transportation risk.
Many-to-Many Game-Theoretic Approach for the Measurement of Transportation Network Vulnerability
Authors: Lownes Nicholas E. , Wang Qixing , Ibrahim Saleh , Ammar Reda A. , Rajasekaran Sanguthevar , Sharma Dolly
Published: February 2012

The vulnerability of a transportation network is strongly correlated with the ability of the network to withstand shocks and disruptions. A robust network with strategic redundancy allows traffic to be redistributed or reassigned without unduly compromising system performance. High-volume edges with limited alternative paths represent system vulnerabilities—a feature of transportation networks that has been exploited to identify critical components. A mixed-strategy, stochastic game-theoretic approach is presented for the measurement of network vulnerability. This method is designed to incorporate all origins and destinations in a network in a computationally efficient manner. The presented method differs from previous efforts in that it provides a many-to-many measure of vulnerability and edge-based disruptions that may not reside on a common path. A game that considers all possible origin–destination pairs is constructed between a router, which seeks minimum cost paths for travelers, and a network tester, which maximizes travel cost by disabling edges within the network. The method of successive averages is used for routing probabilities, and a weighted entropy function is employed to compute edge-disruption probabilities. The method is demonstrated on a small example network and then applied to the Sioux Falls, South Dakota, network. Results indicate good correspondence with a previous method that used equilibrium assignment and rapid solution convergence.
Capacitated-Vehicle Routing Problem with Backhauls on Trees
Authors: Kumar Roshan , Unnikrishnan Avinash , Waller S. Travis
Published: February 2012

The capacitated-vehicle routing problem (CVRP) is a classical problem that has been well studied by the transportation science community. A special case of the CVRP in which the network is constrained to have a tree structure (TCVRP) is studied here. Such tree networks arise when the cost of constructing and maintaining roads is much more than the routing cost—or when the transportation network consists of a main highway (e.g., Interstate system) and the customer locations are located off the highway. A new variant of the TCVRP, in which the customers are divided into two subsets—line haul and backhaul customers (TCVRPB)—is introduced in this paper. Line haul customers require delivery from the depot, and backhaul customers have supply that needs to be delivered to the depot. In any vehicle tour, line haul customers must be serviced before backhaul customers. The TCVRPB's relationship to the two-dimensional bin-packing problem is studied and, with the use of that problem, conditions for the lower bound on the problem are derived. An integer-programming (IP) formulation of the problem is presented. A two-approximation algorithm, which gives a feasible set of vehicle routes and customer assignments, is also presented. The problem is tested on two real-world treelike networks of varying sizes and on a randomly generated test network. The IP formulation works exceptionally well on small and medium-sized networks, and the gap between the approximation algorithm and the IP solution did not exceed 2% for nine of the 12 problem instances tested.
Methodology for Locating Link Count Sensors that Accounts for Reliability of Prior Estimates from Origin–Destination Matrices
Authors: Simonelli Fulvio , Papola Andrea , Marzano Vittorio , Vitiello Iolanda
Published: February 2012

The paper proposes an innovative methodology for addressing the issue of the location of optimal link count sections on the basis of the proposition of a reliability measure in which the prior accuracy of the estimate of the origin–destination (O-D) matrix, that is, its statistical distribution rather than its prior punctual estimate, is explicitly considered, together with its posterior distribution conditioned on a given subset of link count locations. The proposed measure, under the mild assumptions of prior normal distribution and through appropriate algebraic rotations of the reference system, is proved not to depend on the unknown values of the counted flows; this is actually the key point that allows for effective implementation of a fast and operational procedure that is based on this mathematical framework. As an example, toy network and real network applications are presented to show how a heterogeneous level of knowledge across O-D pairs may lead to the choice of counting sections different from those resulting from the commonly adopted procedures. The proposed methodology allows for a more effective theoretical interpretation of the phenomenon and leads to an extremely efficient computational procedure—suitable also in real-size networks—whose results outperform those obtained with the methods currently available in the literature.
Multiobjective Optimization of Signal Timings for Two-Stage, Midblock Pedestrian Crosswalk
Authors: Ma Wanjing , Liu Yue , Xie Hanzhou , Yang Xiaoguang
Published: February 2012

To improve convenience and safety for pedestrians, signalized two-stage, midblock pedestrian crosswalks are increasingly being installed in highly populated areas in developing countries such as China. This paper presents a multiobjective optimization model and its solution algorithm for optimal control of a two-stage, midblock crosswalk on a street with both vehicular and pedestrian traffic. The proposed model aims to produce the optimal signal timings at the crosswalk to accommodate both traffic modes and to adjust the offsets of the pedestrian signals for the two stages concurrently to minimize pedestrian delays and relieve congestion at a central refuge island, the safe area for pedestrians to stop. The proposed model and algorithm have three distinguishing features: (a) they explicitly model pedestrian delays at the two-stage controlled crosswalk, including delays at both the curbside and the central refuge island; (b) they model the number of pedestrians waiting on the central refuge island according to the change in signal timing; and (c) they have application in a multiobjective optimization approach to study the effectiveness of mid-block crosswalk control under conditions in which the priorities between vehicular and pedestrian traffic differ. A heuristic based on nondominated sorting genetic algorithm II was designed to solve the model and generate the Pareto solution set for signal timings. The results of the case study showed that the proposed model would help traffic practitioners, researchers, and authorities properly design signal timing plans and central refuge islands for two-stage midblock pedestrian crosswalks.
Does Proximity to Activity-Inducing Facilities Explain Lower Rates of Physical Activity by Low-Income and Minority Populations?
Authors: Deka Devajyoti , Connelly Mary
Published: February 2012

As in the rest of the nation, low-income and minority populations in New Jersey have higher rates of obesity and lower rates of participation in physical activity. This study examined whether a lower level of geographic proximity to activity-inducing infrastructure and facilities, including bicycling routes and gymnasiums, could be a reason for lower rates of participation in physical activity for New Jersey minority populations. Results of past studies revealed that proximity to activity-inducing facilities was generally associated with greater participation in physical activity for the general population. Some study results showed that low-income and minority populations had a lower level of geographic proximity to such facilities. Other studies indicated that proximity to facilities might not have influenced their participation in physical activity to the same extent as the general population. This study made a statewide assessment of proximity to existing fitness facilities, existing bicycling facilities, and programmed bicycling and pedestrian projects in New Jersey. One-way analysis of variance was used to examine if proximity to activity-inducing facilities was lower for low-income and minority populations. Analysis was carried out at the census block group and municipal levels. The results provided no evidence that low-income and minority populations had a lower level of geographic proximity to activity-inducing facilities. The analysis also showed that programmed bicycling and pedestrian projects were favorably located for these populations. The study concluded that the lower rates of participation of low-income and minority populations in New Jersey were caused by behavioral factors rather than proximity to facilities.
Estimation of Frequency and Length of Pedestrian Stride in Urban Environments with Video Sensors
Authors: Saunier Nicolas , Husseini Ali El , Ismail Karim , Morency Catherine , Auberlet Jean-Michel , Sayed Tarek
Published: February 2012

An emphasis on active modes of transportation, that is, walking and cycling, has recently been renewed amid concerns for the environment and public health. However, the focus of research and practice that these modes have traditionally received is secondary to that received by motorized modes. As a consequence, the data on pedestrians (in particular, microscopic data) required for analysis and modeling are lacking. For instance, accurate data on the length of individual stride are not available in the transportation literature. This paper proposes a simple method to extract frequency and length of pedestrian stride automatically from video data collected nonintrusively in outdoor urban environments. The walking speed of a pedestrian oscillates during each stride; the oscillation can be identified through the frequency analysis of the speed signal. The method was validated with real-world data collected in Rouen, France, and Vancouver, Canada, where the root mean square errors for stride length were 6.1 and 5.7 cm, respectively. A method to distinguish pedestrians from motorized vehicles is proposed and used to analyze the 50 min of the Rouen data set to provide the distributions of stride frequency and length.
The Emergence of Enlightened Anthropocentrism in Ecological Restoration
Authors: Keulartz Jozef
Published: March 2012

Over the past decade a shift can be noticed from ecological restoration to ecological design, where ecological design stands for a technocratic approach that courts hubris and mastery rather than humility and self-restraint. Following Eric Higgs, this shift can be seen as a “hyperactive and heedless response“ to global environmental change, especially climate change. The new technocratic approach may be best characterized as enlightened (or prudential) anthropocentrism, where nature is only allowed that degree of agency which is required to deliver the services that are essential for human well-being. It is not only questionable if we have the scientific and technical abilities to purposeful design ecosystems that will serve our needs, but also if the new approach will be sufficient to protect biodiversity in the long run.
Permanent anosmia and ageusia after resection of a left temporoinsular low-grade glioma: anatomofunctional considerations
Authors: Ribas Eduardo Santamaria Carvalhal , Duffau Hugues
Published: March 2012

Five percent of the general population has olfactory or gustatory disorders, although most do not complain about it. However, in some cases, these symptoms can be disabling and may affect quality of life. Anosmia was reported as a possible complication following head injury and neurosurgical procedures, particularly after the resection of tumors located in the anterior fossa and the treatment of aneurysms in the anterior circulation. Nonetheless, in all of these situations, olfactory dysfunction could be explained by damage to the peripheral olfactory system.

Here, the authors report a case of complete anosmia associated with ageusia following awake resection of a low-grade glioma involving the left temporoinsular region, with no recovery during a follow-up of 3 years. The frontal lobe was not retracted, and the olfactory tract was not visualized during surgery; therefore, postoperative anosmia and ageusia are likely explained by damage to the cortex and central pathways responsible for these senses. The authors suggest that the patient might have had a subclinical right hemianosmia before surgery, which is a common condition. After resection of the central structures critical for smell and taste processing in the left hemisphere, the patient could have finally had bilateral and complete olfactory and gustatory loss.

This is the first known report of permanent anosmia and ageusia following glioma surgery. Because these symptoms might have been underestimated, more attention should be devoted to olfaction and taste, especially with regard to possible subclinical preoperative deficit.
Differences in pelvic parameters among Mexican, Caucasian, and Asian populations
Authors: Zárate-Kalfópulos Barón , Romero-Vargas Samuel , Otero-Cámara Eduardo , Correa Victor Correa , Reyes-Sánchez Alejandro
Published: March 2012

Object

The aim of this study was to describe the pelvic parameters in a sample of healthy Mexican volunteers and to compare them with previously reported data for Caucasian and Asian populations.

Methods

This was a transversal study that included a sample population of healthy Mexican volunteers. Age, sex, and lateral radiographs of the lumbosacral region with the individual standing to obtain the pelvic parameters of pelvic tilt (PT), sacral slope (SS), pelvic incidence (PI), and lumbar lordosis (LL) were recorded in each volunteer. The data were compared with those previously published for Caucasian and Asian individuals.

Results

In total, 202 Mexican individuals (81 men and 121 women; mean age 46.5 years, range 18–85 years) were included. There were statistically significant differences between the Mexican and Caucasian control group with respect to PT (11.9° vs 15.78°, respectively) and PI (51.91° vs 56.68°, respectively). Comparison with the Asian population showed statistically significant differences in relation to the Mexican group in terms of the PT (11.5° vs 15.78°), PI (47.8° vs 56.68°), and SS (36.3° vs 40.89°). The mean LL was 60.17° for the Mexican group, 52.3° for the Asian group, and 61.3° for the Caucasian group. A significant difference in LL was found between the Mexican and Asian populations (p < 0.0001).

Conclusions

A comparison of the values for pelvic parameters and lumbar lordosis across the different population samples revealed statistically significant differences, which can be attributed to the ethnic origin of the individuals.
On the coupled response to ice-shelf basal melting
Authors: Little Christopher M. , Goldberg Daniel , Gnanadesikan Anand , Oppenheimer Michael
Published: February 2012

Ice-shelf basal melting is tightly coupled to ice-shelf morphology. Ice shelves, in turn, are coupled to grounded ice via their influence on compressive stress at the grounding line (‘ice-shelf buttressing’). Here, we examine this interaction using a local parameterization that relates the basal melt rate to the ice-shelf thickness gradient. This formulation permits a closed-form solution for a steady-state ice tongue. Time-dependent numerical simulations reveal the spatial and temporal evolution of ice-shelf/ice-stream systems in response to changes in ocean temperature, and the influence of morphology-dependent melting on grounding-line retreat. We find that a rapid (<1 year) re-equilibration in upstream regions of ice shelves establishes a spatial pattern of basal melt rates (relative to the grounding line) that persists over centuries. Coupling melting to ice-shelf shape generally, but not always, increases grounding-line retreat rates relative to a uniform distribution with the same area- average melt rate. Because upstream ice-shelf thickness gradients and retreat rates increase nonlinearly with thermal forcing, morphology-dependent melting is more important to the response of weakly buttressed, strongly forced ice streams grounded on beds that slope upwards towards the ocean (e.g. those in the Amundsen Sea).
Stain Resistance of Cotton Fabrics before and after Finishing with Admicellar Polymerization
Authors: Hanumansetty Srinivas , Maity Jayanta , Foster Rod , O’Rear Edgar A.
Published: March 2012

Environmental concerns related to perfluoroctanoic acid (PFOA) led to a re-examination of the methods for imparting stain resistance and stain repellency to textiles. Non-PFOA fluoropolymer finishes have been formed on cotton knits by admicellar polymerization, a surface analogue of emulsion polymerization. Fabric samples were characterized by a drop test, contact angle measurements, SEM, elemental analysis and durability studies. Stain resistance and stain release properties were assessed by reflectance and AATCC tests with results comparing favorably with swatches from commercially available garments. Admicellar polymerization enabled the formation of durable finishes that exhibited high performance in stain resistance and stain repellency.
Role of SDF1/CXCR4 Interaction in Experimental Hemiplegic Models with Neural Cell Transplantation
Authors: Arimitsu Nagisa , Shimizu Jun , Fujiwara Naruyoshi , Takai Kenji , Takada Erika , Kono Takao , Ueda Yuji , Suzuki Tomoko , Suzuki Noboru
Published: February 2012

Much attention has been focused on neural cell transplantation because of its promising clinical applications. We have reported that embryonic stem (ES) cell derived neural stem/progenitor cell transplantation significantly improved motor functions in a hemiplegic mouse model. It is important to understand the molecular mechanisms governing neural regeneration of the damaged motor cortex after the transplantation. Recent investigations disclosed that chemokines participated in the regulation of migration and maturation of neural cell grafts. In this review, we summarize the involvement of inflammatory chemokines including stromal cell derived factor 1 (SDF1) in neural regeneration after ES cell derived neural stem/progenitor cell transplantation in mouse stroke models.
Sequence Variants and Haplotype Analysis of Cat ERBB2 Gene: A Survey on Spontaneous Cat Mammary Neoplastic and Non-Neoplastic Lesions
Authors: Santos Sara , Bastos Estela , Baptista Cláudia S. , Sá Daniela , Caloustian Christophe , Guedes-Pinto Henrique , Gärtner Fátima , Gut Ivo G. , Chaves Raquel
Published: March 2012

The human ERBB2 proto-oncogene is widely considered a key gene involved in human breast cancer onset and progression. Among spontaneous tumors, mammary tumors are the most frequent cause of cancer death in cats and second most frequent in humans. In fact, naturally occurring tumors in domestic animals, more particularly cat mammary tumors, have been proposed as a good model for human breast cancer, but critical genetic and molecular information is still scarce. The aims of this study include the analysis of the cat ERBB2 gene partial sequences (between exon 17 and 20) in order to characterize a normal and a mammary lesion heterogeneous populations. Cat genomic DNA was extracted from normal frozen samples (n = 16) and from frozen and formalin-fixed paraffin-embedded mammary lesion samples (n = 41). We amplified and sequenced two cat ERBB2 DNA fragments comprising exons 17 to 20. It was possible to identify five sequence variants and six haplotypes in the total population. Two sequence variants and two haplotypes show to be specific for cat mammary tumor samples. Bioinformatics analysis predicts that four of the sequence variants can produce alternative transcripts or activate cryptic splicing sites. Also, a possible association was identified between clinicopathological traits and the variant haplotypes. As far as we know, this is the first attempt to examine ERBB2 genetic variations in cat mammary genome and its possible association with the onset and progression of cat mammary tumors. The demonstration of a possible association between primary tumor size (one of the two most important prognostic factors) and the number of masses with the cat ERBB2 variant haplotypes reveal the importance of the analysis of this gene in veterinary medicine.
Variation in Stability of Endogenous Reference Genes in Fallopian Tubes and Endometrium from Healthy and Ectopic Pregnant Women
Authors: Gebeh Alpha K. , Marczylo Emma L. , Amoako Akwasi A. , Willets Jonathon M. , Konje Justin C.
Published: March 2012

RT-qPCR is commonly employed in gene expression studies in ectopic pregnancy. Most use RN18S1, β-actin or GAPDH as internal controls without validation of their suitability as reference genes. A systematic study of the suitability of endogenous reference genes for gene expression studies in ectopic pregnancy is lacking. The aims of this study were therefore to evaluate the stability of 12 reference genes and suggest those that are stable for use as internal control genes in fallopian tubes and endometrium from ectopic pregnancy and healthy non-pregnant controls. Analysis of the results showed that the genes consistently ranked in the top six by geNorm and NormFinder algorithms, were UBC, GAPDH, CYC1 and EIF4A2 (fallopian tubes) and UBC and ATP5B (endometrium). mRNA expression of NAPE-PLD as a test gene of interest varied between the groups depending on which of the 12 reference genes was used as internal controls. This study demonstrates that arbitrary selection of reference genes for normalisation in RT-qPCR studies in ectopic pregnancy without validation, risk producing inaccurate data and should therefore be discouraged.