bluuebunny/crossref_metadata_2025 huggingface dataset:
Integration of a Capacity-Constrained Workplace Choice Model: Recent Developments and Applications with an Agent-Based Simulation in Singapore
Authors: Vitins Basil J. , Erath Alexander , Axhausen Kay W.
Published: January 2017

Destination choice models can be embedded in transport and land use models to understand travel and location choice behavior and to forecast scenarios. Utility-maximizing destination choice models can account for individual behavior and make them suitable for agent-based models, while processing destination capacities is also in line with agent-based modeling. This paper addresses the possibility and impact of introducing capacity constraints, their effect on choice behavior, and the feasibility of applying an approach like this in agent-based microsimulations with individual characteristics for each agent. Here, a comprehensive workplace choice model and its application in a large-scale simulation case study for Singapore are described; one technical and one methodological achievement are highlighted. Technical achievement benefits from recent computational advances; the workplace choice model is estimated with a comprehensive utility function on a large data set with 103 destinations. Reasonable model fit and robust parameters are achieved while obviating sampling techniques; resulting parameters are efficiently applied to the entire 5.4 million Singapore population and validated with survey data. For methodological innovation, capacity limitations are introduced at workplaces to avoid oversaturation. A robust optimization method based on shadow prices is proposed to accommodate capacity limitations at all workplaces during the choice model application defined above. The proposed method efficiently assigns commuters to unused workplaces while respecting individual commuter preferences. Validation of the simulation results, by comparing travel time distributions for commuting trips reported in travel diary data, shows that the model fits well with observed data.
Modeling Carsharing with the Agent-Based Simulation MATSim: State of the Art, Applications, and Future Developments
Authors: Ciari Francesco , Balac Milos , Axhausen Kay W.
Published: January 2017

Extensive literature already exists on carsharing and other shared modes, but understanding their effect on the transportation system requires additional work. One main limit of the existing research is that such modes have been analyzed mostly as isolated systems. As these modes were niche products, it was not easy to include them in comprehensive models of transport, and, in a way, it did not even make sense. But the modes’ current popularity and their expected growth completely change the picture. Transport model systems in which such mobility concepts will be explicitly modeled—along with all other modes—will be crucial in the near future to gain an insight into travel behavior effects and to assess possible future scenarios representing the effect of long-term mobility decisions. This paper describes how carsharing demand is modeled in an activity-based multiagent simulation of transport called MATSim ( www.matsim.org ). The paper draws from a series of papers written by the authors between 2009 and 2015 and is part of a research effort whose ultimate goal is to build a predictive and policy-sensitive model that can be used by practitioners and policy makers to test any type of carsharing scenario. This paper summarizes the work done, provides some examples of applications, addresses current limitations, and briefly reports on ongoing and planned developments.
Microsimulation of Demand and Supply of Autonomous Mobility On Demand
Authors: Azevedo Carlos Lima , Marczuk Katarzyna , Raveau Sebastián , Soh Harold , Adnan Muhammad , Basak Kakali , Loganathan Harish , Deshmunkh Neeraj , Lee Der-Horng , Frazzoli Emilio , Ben-Akiva Moshe
Published: January 2017

Agent-based models have gained wide acceptance in transportation planning because with increasing computational power, large-scale people-centric mobility simulations are possible. Several modeling efforts have been reported in the literature on the demand side (with sophisticated activity-based models that focus on an individual’s day activity patterns) and on the supply side (with detailed representation of network dynamics through simulation-based dynamic traffic assignment models). This paper proposes an extension to a state-of-the-art integrated agent-based demand and supply model—SimMobility—for the design and evaluation of autonomous vehicle systems. SimMobility integrates various mobility-sensitive behavioral models in a multiple time-scale structure comprising three simulation levels: ( a) a long-term level that captures land use and economic activity, with special emphasis on accessibility; ( b) a midterm level that handles agents’ activities and travel patterns; and ( c) a short-term level that simulates movement of agents, operational systems, and decisions at a microscopic granularity. In that context, this paper proposes several extensions at the short-term and midterm levels to model and simulate autonomous vehicle systems and their effects on travel behavior. To showcase these features, the first-cut results of a hypothetical on-demand service with autonomous vehicles in a car-restricted zone of Singapore are presented. SimMobility was successfully used in an integrated manner to test and assess the performance of different autonomous vehicle fleet sizes and parking station configurations and to uncover changes in individual mobility patterns, specifically in regard to modal shares, routes, and destinations.
Transportation Planning Through Peer-to-Peer Modeling
Authors: Cebelak Meredith , Jin Peter J. , Walton C. Michael
Published: January 2017

With many of today’s metropolitan areas experiencing changes in population and land development faster than the traditional transportation planning efforts can be undertaken, new methods for transportation planning are constantly being explored. This paper presents a novel approach to the transportation planning problem through the use of location-based social networking data and the many-to-many modeling structure of peer-to-peer modeling. With smartphone and tablet use increasing in the United States, many popular social networking sites have begun to include geospatial location in their platforms, and location-based social networking data sources have become attractive data sets for the transportation community because of their ability to be representative of populations and to provide detailed spatial–temporal data. The novel origin–destination estimation method through peer-to-peer modeling is presented, and a case study example of Austin, Texas, provides initial findings through a comparison against a doubly constrained gravity model and an existing origin–destination matrix for the study area. This first look at peer-to-peer modeling for origin–destination estimation revealed the method’s strengths with respect to intrazonal trip estimations and production and attraction estimations and was found to be more computationally efficient than the doubly constrained gravity model.
Using Predicted Bicyclist and Pedestrian Route Choice to Enhance Mode Choice Models
Authors: Broach Joseph , Dill Jennifer
Published: January 2017

Recent advances in bicyclist and pedestrian route choice modeling have shown that a variety of attributes affect the paths chosen for cycling and walking. They also allow one to estimate the effect on route choice of specific network changes, such as new bicycle facilities or pedestrian crossings. Route choices do not, however, tell one anything explicit about changes in decisions to walk or cycle in the first place. Cyclists might go out of their way to use a bike lane or to avoid a busy street, but how do those same features along a potential route influence the choice to cycle instead of using another travel mode? Route choice models are applied to predict the cycling and walking routes considered for a given trip, and the resulting route-level attributes are used to predict trip mode choice. In general, existing route preferences do carry over to mode choice, but with important differences, especially for bicycle facility types and female cyclists. The results show that available off-street paths and low-traffic on-street routes not only draw cyclists from other facilities but also make prospective riders more likely to cycle on a given trip. Gender differences are found for decisions to bicycle, with women showing a lower propensity than men to cycle on a similar trip and also stronger sensitivity to the availability of routes with lower traffic stress. Traffic-calmed streets, such as bicycle boulevards, may be particularly important in reducing the observed bicycling gender gap for everyday travel.
Activity-Based Travel Demand Modeling Framework FEATHERS: Sensitivity Analysis with Decision Trees
Authors: Bao Qiong , Kochan Bruno , Shen Yongjun , Bellemans Tom , Janssens Davy , Wets Geert
Published: January 2017

The decision tree technique is increasingly applied in activity-based travel demand modeling. It has the strength of representing the full complexity of interactions between different variables. However, this complexity often hinders an interpretation of the relative effects of these variables on the activity travel choice. In this study, a sensitivity analysis is performed on decision trees in FEATHERS, an activity-based microsimulation modeling framework, with the purpose of quantitatively measuring the relative effect of input variables involved in the given decision trees on the choice variable. The local and global sensitivity analysis approaches are investigated: ( a) a one-at-a-time approach that predicts the choice frequency distribution by varying selected input variables one after another and keeping all other variables as observed and ( b) the improved Sobol method, which evaluates the effect of an input variable while all other variables are varied as well. With the application of these two approaches to two representative decision trees concerning work-related activity (i.e., commute trip) choice and transport mode choice for work-related activities in the FEATHERS framework, consistent results concerning the key input variables for these two decision trees are derived, and some extra insights are gained from each of the approaches.
Exploring the Role of Location in Dynamics of the Birth and Death of Business Establishments: Case Study Analysis of Santa Barbara County, California
Authors: Ravulaparthy Srinath K. , Goulias Konstadinos G.
Published: January 2017

Integrated models of land use and transportation are aimed at addressing regional issues related to congestion, mobility, and economic competitiveness. Integral to these model systems is freight transport, which plays a huge role in the economic vitality of the region in the form of distribution and complex interactions between various stakeholders. Within this context, it is therefore critical to capture and describe accurately the behavioral dynamics of these stakeholders (or firms) in the region, including modeling various life-cycle stages, such as birth, death, growth and decline, and migration patterns. This study focused on dynamics of the birth and death of firms by considering as determinants their internal attributes (size, age, and growth) and external attributes, such as market area characteristics, agglomeration economies, transportation access, and network centrality indexes describing advantage, significance, and properties of a location. This microanalysis was based on an assembled panel of all business establishments in Santa Barbara County in California between 1990 and 2010. Empirical results from this study revealed the presence of spatial and temporal heterogeneity in the birth and death of firms. Highly central locations in the region, such as downtown areas, have a higher probability of firm formation, along with a lower likelihood for firm closures. Professional service firms located along major local and collector roads have higher probabilities of survival. In addition, for their economic survival, retail trade firms favor access to locations along roadways that serve as pass-through connectors in the region. Results also suggest that events of birth and death are triggered primarily by changes in firm internal attributes, such as employment size, revenues, and growth rates.
Evaluating Transport User Benefits: Adjustment of Logsum Difference for Constrained Travel Demand Models
Authors: Winkler Christian
Published: January 2017

Transport user benefits are of great importance in cost–benefit analysis when transport projects are appraised. Generally, these benefits have the greatest effect on the results of cost–benefit analyses. It is common to adopt the consumer surplus for calculating transport user benefits. The consumer surplus measure is based on the underlying demand model and follows from the integration of the demand curve. If the popular logit model is used for forecasting travel demand, a consumer surplus measure takes a closed form that is easy to calculate. Furthermore, in cost–benefit analyses the change in consumer surplus between an initial and final state is needed; the change can be easily derived by the difference of the logsums of the two states. This logsum approach is proven and correct for travel demand models based on the logit model without multiple constraints. However, for travel demand models dealing with two or more sets of constraints, the logsum approach fails. In this paper, a mathematical approach is described for a transport user benefits measure that corresponds to the consumer surplus and is universal for all travel demand models with constraints. The measure for a doubly constrained trip distribution is derived. The applicability of the derived approach is shown by a simple example.
Simulated Effects of the Location of High-Speed Rail Stations on Land Development: Case Study of the Lisbon Metropolitan Area, Portugal
Authors: Shen Yu , Chen Guineng , de Abreu e Silva João , Martínez Luis Miguel
Published: January 2017

This paper studies the effects of high-speed rail (HSR) on land cover change in the Lisbon metropolitan area (LMA) in Portugal according to a bilevel cellular automata/agent-based modeling framework. The model incorporates spatial mixed logit models at the local level and panel simultaneous equations models at the regional level. The regional submodel generates socioeconomic activities that are input into the local submodel for land development. The regional activities are also influenced by the local outputs. A backcasting simulation is executed to validate the model on the basis of the actual land cover change from 1991 to 2011. Five scenarios are then designed according to the numbers and the locations of HSR stations in the LMA. The simulation shows that the unbuilt land covers are largely developed by 2031, regardless of the inauguration of HSR. Under the scenarios with HSR, because of the dramatic improvement of accessibility, the land cover change speed is largely accelerated. With an additional station on the southern bank of the Tagus River, the overall accessibility does not further increase from the scenario with only one HSR station. Thus, the total land development remains similar. The enhanced access to the HSR service from the additional station contributes to the redistribution of the land cover change activities by moving them slightly southeastward. The results highlight the effect that station location could have on land cover change, pointing out the importance of carefully choosing the location.
Choice Set Imputation in Atomistic Spatial Choice Models
Authors: Zolfaghari Alireza , Polak John , Sivakumar Aruna
Published: January 2017

Constructing the universal choice set in spatial choice models developed at the level of elemental alternatives (atomistic models) is challenging because disaggregate data on the attributes of nonchosen alternatives are often not available. Even when the disaggregate data on nonchosen alternatives are available, matching two data sources will inevitably be error prone given that they might be collected at different times and they might have different coding for categorical variables. An important practical question in the estimation of such atomistic models, therefore, is how to construct the universal choice set in the absence of disaggregate data on the attributes of the nonchosen alternatives. This paper presents a novel approach for spatial imputation of attributes of nonchosen alternatives for estimation and application of atomistic spatial choice models in the absence of disaggregate data. The proposed approach uses the iterative proportional fitting algorithm to impute the attributes of nonchosen alternatives from aggregated data on elemental alternatives. The proposed method is validated with a Monte Carlo experiment and applied to real data in the London residential location choice context.
Network Connectivity for Low-Stress Bicycling
Authors: Furth Peter G. , Mekuria Maaza C. , Nixon Hilary
Published: January 2017

When streets with high traffic stress—on which the mainstream population is unwilling to ride a bike—are removed, the remaining network of streets and paths can be fragmented and poorly connected. This paper describes the development of methods to visualize and to analyze the lack of connectivity in a low-stress bicycling network. A proposed measure to evaluate bicycling networks is the fraction of origin–destination pairs, which are connected without the use of high stress, without excessive detour, and with the origin–destination pairs weighted by travel demand. A new method is proposed to classify segments and crossings into four levels of traffic stress (LTS) on the basis of Roger Geller’s classification of the cyclist population and Dutch design standards, which are known to attract the mainstream population. As a case study, every street in San Jose, California, was classified by LTS value. Maps that showed only lower stress links revealed a city divided into islands within which low-stress bicycling was possible, but these islands were separated from one another by barriers that could be crossed only with the use of high-stress links. The fraction was 4.7% of home-to-work trips up to 6 mi long that were connected at a low LTS value. The figure would almost triple if a modest slate of improvements were implemented to connect low-stress streets and paths with each other.
Bicycling to Rail Stations in New Jersey
Authors: Harvey Elizabeth , Brown Charles T. , DiPetrillo Stephanie , Kay Andrew
Published: January 2017

The purpose of this study was to document the conditions of the built environment and the characteristics of commuters who bicycle to rail stations in New Jersey. This research was quantified through several data-collection activities: ( a) observational counts of bicycle-to-rail commuters, ( b) inventories of bicycle infrastructure, ( c) an intercept survey of bicycle-to-rail commuters, and ( d) a focus group of bicycle-to-rail commuters. These data showed that bicycling to rail stations was an important yet underserved part of the commuter network in New Jersey. The data also showed that improvements to bicycling infrastructure at and around stations were vital to increase the rate of bicycle-to-rail commuters. Together, these activities provided detailed information about bicycle-to-rail commuters, as well as a benchmark for the evaluation of future conditions. The study found that those who bicycled to stations typically were male, white, and between the ages of 25 and 44 years. Most of these riders had earned college or postgraduate degrees and were members of a high-earning household. Survey and focus group participants were concerned mostly about safety on roads and at stations. Participants advocated for more bicycle lanes, on-street lighting, police security at stations, and better bicycle parking. Finally, the station inventory revealed that bicycle parking could be expanded at some stations to and from which bicycling was popular. The road inventory showed that most roads had speed limits at or below 25 mph and fewer than four lanes. However, just 2% had any on-street bicycle infrastructure.
When a Diet Prompts a Gain: Impact of a Road Diet on Bicycling in Davis, California
Authors: Gudz Eric Matthew , Fang Kevin , Handy Susan L.
Published: January 2017

With the goal to improve the integration of multiple travel modes into traditional roadway designs, many jurisdictions have considered road diets, characterized by reductions in vehicular traffic lanes and reallocation of right-of-way for other modes. Studies show that road diets can improve safety without slowing automobile traffic, but benefits for pedestrians and bicyclists have not been widely documented. To address this gap, this study examined the effects of a road diet project in Davis, California. Data were collected on the number of bicyclists and pedestrians at key intersections and automobile travel times along the corridor before and after the road diet treatment. Every intersection that was studied experienced a statistically significant increase in the number of bicyclists during the morning or the evening peak period or during both. On average across all intersections studied along the corridor, the number of bicyclists who used Fifth Street increased by 243%, but the change in pedestrian volume was not statistically significant. Contrary to common fears about road diets, automobile travel times decreased a statistically significant amount during the evening peak. This study demonstrated that road diets can benefit bicyclists without negative effects on automobile travelers.
Estimating Current and Potential Bicycle Use for Statewide Planning
Authors: Grover David , Wygonik Erica , Bucossi Sommer , Bell Amy , Piper Sam , Brewer-Colie Katelin
Published: January 2017

As interest in bicycling for transportation and recreation has increased, state transportation agencies and other planning organizations must prioritize ways in which to spend their limited resources. This paper describes a geographic information system–based analysis that categorizes state-owned highways across Vermont on the basis of potential bicycle use through the leverage of readily available data. This methodology allows a planning agency to make decisions on the basis of statewide information and avoids the costs of a traditional travel demand model. It informs decision makers about where to invest additional funds to improve on-road bicycle facilities and to prioritize maintenance to maximize value. It also provides the groundwork for bicycle-related performance standards and to identify critical gaps in high-demand bicycle corridors.
User Behavior of Bikesharing Systems Under Demand–Supply Imbalance
Authors: Hsu Yu-Ting , Kang Lei , Wu Yi-Hsuan
Published: January 2017

Bikesharing systems have been expanding rapidly. They are recognized as a strategic tool to integrate transit and to foster sustainable transportation in urban areas. A critical problem that arises in the planning and deployment of a bikesharing system lies in demand–supply imbalance as the result of the spatiotemporal dynamics of demand patterns. The problem manifests itself in situations in which no bikes are available to rent and no docks are available for bike return at certain popular stations. This study developed a framework for modeling user behavior in response to such situations. Particular emphasis was placed on user on-site choice behavior and the behavioral aspect related to wait time if a decision to wait for the next bike or dock was made. These behaviors were approached with the use of a discrete choice model and a duration model, respectively. Further, a discrete-continuous process was proposed to address the potential interrelation that existed between the choice to wait and the length of waiting time to be endured. Within the developed framework, the models were estimated on the basis of the data from a revealed preference–stated preference survey conducted on the YouBike system in Taipei, Taiwan. The estimation results provided insights into user familiarity and uncertainty toward the system, travel situation, or environment and the associated effects on user behavior of a bikesharing system under a demand–supply imbalance.
Visibility of Two-Wheelers Approaching Left-Turning Vehicles Compared with Other Hazards Under Nighttime Conditions at Urban Signalized Intersections
Authors: Spivey Heath , Pulugurtha Srinivas S.
Published: January 2017

In the past, researchers have investigated ways to increase the conspicuity of two-wheelers (i.e., motorcycles, mopeds, scooters, and other motorized vehicles) under daytime conditions. However, only a few researchers have analyzed their conspicuity under nighttime conditions. The aim of this study was to evaluate the visibility of two-wheelers encountered by left-turning motorists at urban intersections under nighttime conditions, and compare them with other hazards. A low-fidelity simulator was used to collect data and perform evaluations. The simulator presented a series of videos from a motorist’s perspective, while a passenger vehicle was positioned in the permitted left-turn lane at a signalized intersection. During each video the study participants were instructed to determine whether a left-turn maneuver was safe under the given set of nighttime traffic conditions. The response times for 30 participants were recorded and totaled 627 responses. The observed response times to a two-wheeler were not different from the response times to a passenger vehicle with two headlights. However, the response times were significantly shorter than the times to recognize no hazard or a two-wheeler with no headlight. The conspicuity issues that pertain to two-wheelers in daytime and nighttime conditions were not observed to be the same. Further, the same treatments proposed for two-wheelers in daytime conditions may not be as beneficial or even needed during nighttime driving.
Modeling Route Choice of Utilitarian Bikeshare Users with GPS Data
Authors: Khatri Ranjit , Cherry Christopher R. , Nambisan Shashi S. , Han Lee D.
Published: January 2017

To understand a bicyclist’s route choice is difficult, given the many factors that influence the attractiveness of different routes. The advent of low-cost GPS devices has made route choice analysis more precise. Bikeshare, with instrumented bikes, allows for better assessment of revealed route preference of a large subpopulation of cyclists. This study used GPS data obtained from 9,101 trips made by 1,866 users of Grid Bikeshare, Phoenix, Arizona. This unique bikeshare system relied on Social Bicycles’ onboard telematics, which allowed nonstation origins and destinations, and operated on a grid street network. The system enabled unique route choice analysis. The trips studied included only direct utilitarian trips. Circuitous trips that could have included multiple destinations or could have been recreational trips were removed. The analysis focused on facility use assessment and route choice behavior. The results were compared between two categories of bikeshare users: registered users and casual users. Registered users made shorter trips on roads with low volume and preferred bike-specific infrastructure. A path size logit model was used to model route choice. Riders were sensitive to travel distance, with little deviation from the shortest path to use more bike-friendly infrastructure. Travel on the bike-specific facilities was equivalent to a decrease in distance by 44.9% (compared with 53.3% for casual users). Left turns imposed higher disutility than right turns did for casual users. The proportion of one-way segments, annual average daily traffic values, and length of trip had a negative influence on route choice, and a number of signalized intersections had a positive influence on route selection. The results were also compared with those of earlier studies.
Surgical benefits of combined awake craniotomy and intraoperative magnetic resonance imaging for gliomas associated with eloquent areas
Authors: Motomura Kazuya , Natsume Atsushi , Iijima Kentaro , Kuramitsu Shunichiro , Fujii Masazumi , Yamamoto Takashi , Maesawa Satoshi , Sugiura Junko , Wakabayashi Toshihiko
Published: January 2017

OBJECTIVE

Maximum extent of resection (EOR) for lower-grade and high-grade gliomas can increase survival rates of patients. However, these infiltrative gliomas are often observed near or within eloquent regions of the brain. Awake surgery is of known benefit for the treatment of gliomas associated with eloquent regions in that brain function can be preserved. On the other hand, intraoperative MRI (iMRI) has been successfully used to maximize the resection of tumors, which can detect small amounts of residual tumors. Therefore, the authors assessed the value of combining awake craniotomy and iMRI for the resection of brain tumors in eloquent areas of the brain.

METHODS

The authors retrospectively reviewed the records of 33 consecutive patients with glial tumors in the eloquent brain areas who underwent awake surgery using iMRI. Volumetric analysis of MRI studies was performed. The pre-, intra-, and postoperative tumor volumes were measured in all cases using MRI studies obtained before, during, and after tumor resection.

RESULTS

Intraoperative MRI was performed to check for the presence of residual tumor during awake surgery in a total of 25 patients. Initial iMRI confirmed no further tumor resection in 9 patients (36%) because all observable tumors had already been removed. In contrast, intraoperative confirmation of residual tumor during awake surgery led to further tumor resection in 16 cases (64%) and eventually an EOR of more than 90% in 8 of 16 cases (50%). Furthermore, EOR benefiting from iMRI by more than 15% was found in 7 of 16 cases (43.8%). Interestingly, the increase in EOR as a result of iMRI for tumors associated mainly with the insular lobe was significantly greater, at 15.1%, than it was for the other tumors, which was 8.0% (p = 0.001).

CONCLUSIONS

This study revealed that combining awake surgery with iMRI was associated with a favorable surgical outcome for intrinsic brain tumors associated with eloquent areas. In particular, these benefits were noted for patients with tumors with complex anatomy, such as those associated with the insular lobe.
Emergency department evaluation and 30-day readmission after craniotomy for primary brain tumor resection in New York State
Authors: Missios Symeon , Bekelis Kimon
Published: January 2017

OBJECTIVE

Fragmentation of care has been recognized as a major contributor to 30-day readmissions after surgical procedures. The authors investigated the association of evaluation in the hospital where the original procedure was performed with the rate of 30-day readmissions for patients presenting to the emergency department (ED) after craniotomy for primary brain tumor resection.

METHODS

A cohort study was conducted, involving patients who were evaluated in the ED within 30 days after discharge following a craniotomy for primary brain tumor resection between 2009 and 2013, and who were registered in the Statewide Planning and Research Cooperative System (SPARCS) database of New York State. A propensity score–adjusted model was used to control for confounding, whereas a mixed-effects model accounted for clustering at the hospital level.

RESULTS

Of the 610 patients presenting to the ED, 422 (69.2%) were evaluated in a hospital different from the one where the original procedure was performed (28.9% were readmitted), and 188 (30.8%) were evaluated at the original hospital (20.3% were readmitted). In a multivariable analysis, the authors demonstrated that being evaluated in the ED of the original hospital was associated with a decreased rate of 30-day readmission (OR 0.64, 95% CI 0.41–0.98). Similar associations were found in a mixed-effects logistic regression model (OR 0.63, 95% CI 0.40–0.96) and a propensity score–adjusted model (OR 0.64, 95% CI 0.41–0.98). This corresponds to one less readmission per 12 patients evaluated in the hospital where the original procedure was performed.

CONCLUSIONS

Using a comprehensive all-payer cohort of patients in New York State who were evaluated in the ED after craniotomy for primary brain tumor resection, the authors identified an association of assessment in the hospital where the original procedure was performed with a lower rate of 30-day readmissions. This underscores the potential importance of continuity of care in readmission prevention for these patients.
Midterm results of T-stent–assisted coiling of wide-necked and complex intracranial bifurcation aneurysms using low-profile stents
Authors: Aydin Kubilay , Sencer Serra , Barburoglu Mehmet , Berdikhojayev Mynzhylky , Aras Yavuz , Sencer Altay , İzgi Nail
Published: January 2017

OBJECTIVE

Coiling of wide-necked and complex bifurcation aneurysms frequently requires implantation of double stents in various configurations. T-stent–assisted coiling involves the nonoverlapping implantation of 2 stents to protect the daughter vessels of bifurcation and is followed by coiling of the aneurysm. The authors studied the feasibility, efficacy, and safety of the T-stent–assisted coiling procedure as well as the midterm angiographic/clinical outcomes of patients with wide-necked bifurcation intracranial aneurysms treated using this technique.

METHODS

The authors retrospectively identified patients with wide-necked bifurcation intracranial aneurysms treated using double-stent–assisted coiling with a T-stent configuration.

RESULTS

Twenty-four patients with 24 aneurysms and a mean of age of 51.91 years were identified. The most common locations were the middle cerebral bifurcation (45.8%) and anterior communicating artery (35.7%). T stentings were performed using low-profile stents. The procedures were performed with a technical success rate of 95.8%, and an immediate total occlusion rate of 79.2% was achieved. We observed periprocedural complications in 16.7% of cases and a delayed thromboembolic event in 4.2%. The complications caused permanent morbidity in 1 patient (4.2%). No deaths occurred. The mean angiographic follow-up duration was 9.3 months. The total occlusion rate at the last follow-up was 81.2%. The recanalization rate was 4.5%. Modified Rankin Scale scores of all patients at the last follow-ups were between zero and 2.

CONCLUSIONS

T-stent–assisted coiling using low-profile stents is a feasible, effective, and relatively safe endovascular technique used to treat wide-necked and complex intracranial aneurysms. The midterm angiographic and clinical outcomes are outstanding.
Hydrocephalus in a patient with an unruptured pial arteriovenous fistula: hydrodynamic considerations, endovascular treatment, and clinical course
Authors: Morales-Gómez Jesús A. , Garza-Oyervides Vicente V. , Arenas-Ruiz José A. , Mercado-Flores Mariana , Elizondo-Riojas C. Guillermo , Boop Frederick A. , de León Ángel Martínez-Ponce
Published: January 2017

Intracranial pial arteriovenous fistulas, also known as nongalenic fistulas, are rare vascular malformations affecting predominantly the pediatric population. Hydrocephalus is an unusual presentation in which the exact pathophysiology is not fully understood. The aim of treatment in these cases is occlusion of the fistula prior to considering ventricular shunting. Here, the authors describe the hydrodynamic considerations of the paravascular pathway and the resolution of hydrocephalus with endovascular treatment of the fistula.
Resolution of the more anteriorly positioned psoas muscle following correction of spinal sagittal alignment from spondylolisthesis: case report
Authors: Syed Hasan R. , Yaeger Kurt , Sandhu Faheem A.
Published: January 2017

Several studies have described the radiographic, histological, and morphological changes to the paraspinal muscle in patients with chronic low-back pain due to degenerative diseases of the spine. Gross anatomical illustrations have shown that the psoas muscle lies lateral to the L4–5 vertebrae and subsequently thins and dissociates from the vertebral body at L5–S1 in a ventrolateral course. A “rising psoas” may influence the location of the lumbar plexus and result in transient neurological injury on lateral approach to the spine. It is postulated that axial back pain may be exacerbated by anatomical changes of paraspinal musculature as a direct result of degenerative spine conditions. To their knowledge, the authors present the first reported case of a more anteriorly positioned psoas muscle and its resolution following correction of spondylolisthesis in a 62-year-old woman. This case highlights the dynamic nature of degenerative spinal disorders and illustrates that psoas muscle position can be affected by sagittal balance. Normal anatomical positioning can be restored following correction of spinal alignment.
Differential Hemispheric Predilection of Microstructural White Matter and Functional Connectivity Abnormalities between Respectively Semantic and Behavioral Variant Frontotemporal Dementia
Authors: Meijboom Rozanna , Steketee Rebecca M.E. , Ham Leontine S. , van der Lugt Aad , van Swieten John C. , Smits Marion
Published: January 2017

Semantic dementia (SD) and behavioral variant frontotemporal dementia (bvFTD), subtypes of frontotemporal dementia, are characterized by distinct clinical symptoms and neuroimaging features, with predominant left temporal grey matter (GM) atrophy in SD and bilateral or right frontal GM atrophy in bvFTD. Such differential hemispheric predilection may also be reflected by other neuroimaging features, such as brain connectivity. This study investigated white matter (WM) microstructure and functional connectivity differences between SD and bvFTD, focusing on the hemispheric predilection of these differences. Eight SD and 12 bvFTD patients, and 17 controls underwent diffusion tensor imaging and resting state functional MRI at 3T. Whole-brain WM microstructure was assessed to determine distinct WM tracts affected in SD and bvFTD. For these tracts, diffusivity measures and lateralization indices were calculated. Functional connectivity was established for GM regions affected in early stage SD or bvFTD. Results of a direct comparison between SD and bvFTD are reported. Whole-brain WM microstructure abnormalities were more pronounced in the left hemisphere in SD and bilaterally— with a slight predilection for the right— in bvFTD. Lateralization of tract-specific abnormalities was seen in SD only, toward the left hemisphere. Functional connectivity of disease-specific regions was mainly decreased bilaterally in SD and in the right hemisphere in bvFTD. SD and bvFTD show WM microstructure and functional connectivity abnormalities in different regions, that are respectively more pronounced in the left hemisphere in SD and in the right hemisphere in bvFTD. This indicates differential hemispheric predilection of brain connectivity abnormalities between SD and bvFTD.
Death of Dementia Patients in Psychiatric Hospitals and Regional Supply of Psychiatric Services: Study of the National Data from 1996 to 2014 in Japan
Authors: Nakanishi Miharu , Niimura Junko , Yamasaki Syudo , Nishida Atsushi
Published: January 2017

Background: Japan designates psychiatric inpatient care for behavior management of individuals with dementia and for helping dementia patients discharge to home. However, there has been no examination of the effectiveness of this strategy.

Objective: The present study investigated the association between dementia and the discharge destination of patients in psychiatric hospitals.

Methods: Data from the National Patient Survey, which is a nationally representative cross-sectional survey of inpatient care, were used. The 96,420 patients with dementia or other mental illness who were discharged from psychiatric hospitals in September of every 3 years from 1996 to 2014 were included in analyses.

Results: Of the 96,420 discharged patients, 13,823 had dementia as the primary disease. Of the 13,823 dementia patients, 3,865 (28.0%) were discharged to home, 3,870 (28.0%) were admitted to a facility or other care settings, 3,574 (25.9%) were admitted to another hospital, and 2,514 (18.2%) died. Patients were more likely to die in psychiatric hospital if their primary disease was dementia, and they had resided in a region that provided fewer home visits for psychiatric nursing care or had available a larger number of psychiatric hospital beds per capita.

Conclusion: Psychiatric inpatient care may be ineffective as a treatment for the challenging behaviors of dementia. A community mental health system for behavior management should be constructed in parallel with a reduction in the number of hospital beds allotted for psychiatric care.
Evidence of a Cardiovascular Function for Microtubule-Associated Protein Tau
Authors: Betrie Ashenafi H. , Ayton Scott , Bush Ashley I. , Angus James A. , Lei Peng , Wright Christine E.
Published: January 2017

Aggregation of tau protein into intracellular deposits is a pathognomonic feature of tauopathies such as Alzheimer’s disease (AD) and lowering tau is a prominent therapeutic strategy under development. However, the physiological function of tau protein is not well known, particularly in the periphery. Lowering tau protein risks disrupting its physiological role leading to unwanted effects. In this study, the presence of tau protein in cardiac tissue is confirmed and the functional role in the cardiovascular system and the consequences of its loss were explored. Isolated right and left atria and small mesenteric arteries from wild type and tau deficient (KO) mice of two age groups (13 and 23 months old) were used to assess cardiovascular phenotypes. Tau KO mice showed an increased systolic blood pressure and cardiac hypertrophy at 13 months, which was accompanied by a significantly lower right atrial rate and a subtle decrease in the maximum contractility to calcium, isoprenaline, and electrical sympathetic nerve stimulation. Aging tau KO mice to 23 months resulted in cardiac hypertrophy with significantly attenuated left atrial contractility, increased blood pressure, and sensitivity of isolated mesenteric arteries to angiotensin II contraction and isoprenaline relaxation compared to their younger counterparts. This study supports a functional role of tau in the heart and loss of this protein leads to a deterioration in cardiovascular performance which worsens with age. Taken together, these results provide insight into the peripheral function of tau protein, and give caution to the therapeutic strategy of lowering tau protein.
Whole body vibration (WBV) following spinal cord injury (SCI) in rats: Timing of intervention
Authors: Manthou Marilena , Abdulla Diana Saad Yousif , Pavlov Stoyan Pavlov , Jansen Ramona , Bendella Habib , Nohroudi Klaus , Stein Gregor , Meyer Carolin , Ozsoy Ozlem , Ozsoy Umut , Behram Kandemir Yasemin , Sarikcioglu Levent , Semler Oliver , Schoenau Eckhard , Dunlop Sarah , Angelov Doychin Nikolov
Published: January 2017

Background: Following spinal cord injury (SCI), exercise training provides a wide range of benefits and promotes activity-dependent synaptic plasticity. Whole body vibration (WBV) in SCI patients improves walking and spasticity as well as bone and muscle mass. However, little is known about the effects of timing or frequency of intervention.

Objective: To determine which WBV-onset improves locomotor and bladder functions and influences synaptic plasticity beneficially.

Methods: SCI was followed by WBV starting 1, 7, 14, 28 days after injury (WBV1, WBV7, etc.) and continued for 12 weeks. Intact animals and those receiving SCI but no WBV (No WBV), SCI plus WBV twice daily (2×WBV) and SCI followed by passive hindlimb flexion-extension (PFE) served as controls. Locomotor [BBB rating, foot stepping angle (FSA) and rump-height index (RHI)] as well as bladder function were determined at 1, 3, 6, 9, and 12 weeks. Following perfusion fixation at 12 weeks, lesion volume and immunofluorescence for astrogliosis (GFAP), microglia (IBA1) and synaptic vesicles (synaptophysin, SYN) were determined.

Results: Compared to the No WBV group, the WB7 and WBV14 groups showed significantly faster speeds of BBB score recovery though this effect was temporary. Considering RHI we detected a sustained improvement in the WBV14 and PFE groups. Bladder function was better in the WBV14, WBV28, 2×WBV and PFE groups. Synaptophysin levels improved in response to WBV7 and WBV14, but worsened after WBV28 in parallel to an increased IBA1 expression. Correlation- and principal components analysis revealed complex relationships between behavioural (BBB, FSA, RHI) and morphological (GFAP, IBA1, SYN) measurements.

Conclusions: WBV started 14 days after SCI provides the most benefit (RHI, bladder); starting at 1day after SCI provides no benefit and starting at 28 days may be detrimental. Increasing the intensity of WBV to twice daily did not provide additional benefit.
Bupivacaine increases the rate of motoneuron death following peripheral nerve injury
Authors: Byram Susanna C. , Byram Scott W. , Miller Nicholas M. , Fargo Keith N.
Published: January 2017

Background: Appropriate management of pain after an injury or surgical procedure has been shown to improve patient outcomes. While infrequent, nerve damage resulting from regional anesthesia can be devastating, however the mechanism remains unknown. Local anesthetics are neurotoxic yet are frequently applied to sites where peripheral nerves are regenerating. Therefore, understanding their effects on injured and growing neurons may have important implications for clinical practice.

Objective: The purpose of this study was to determine if local anesthetics exacerbate the rate of motoneuron death following axotomy.

Methods: Mice were subjected to a unilateral transection of the facial motor nerve, and either normal saline, 2% lidocaine, or 0.75% bupivacaine was placed at the injury site. Four weeks post-axotomy, percent survival was determined by comparing the number of motoneuron cell bodies on the injured side and the uninjured control side.

Results: The average facial motoneuron survival in the saline, lidocaine, and bupivacaine groups 4 weeks after axotomy was 80%, 78% and 35%, respectively.

Conclusion: Our data suggest that bupivacaine exacerbates levels of cell death in injured motoneurons. It has been proposed that once a nerve is damaged, it becomes more susceptible to injury elsewhere along the nerve. Thus, an improved understanding of the effects of local anesthetics on neuron survival and axon regeneration may lead to strategies to identify patients at higher risk for permanent neural deficits after peripheral nerve blocks and/or decrease the risk of neural deficit following peripheral nerve blocks.
Relative Free Radicals Scavenging and Enzymatic Activities of Hippophae rhamnoides and Cassia fistula Extracts: Importance for Cosmetic, Food and Medicinal Applications
Authors: Khan Barkat , Akhtar Naveed , Menaa Bouzid , Menaa Abder , Braga Valdir , Menaa Farid
Published: January 2017

Hippophae rhamnoides L. and Cassia fistula L. extracts have great potential as food, medicinal, or cosmetic ingredients. The aim of our study was to assess their relative antioxidant activities and key enzymatic activities. Thereby, H. rhamnoides’ fruit and C. fistula’s pod extracts were evaluated by spectrophotometry, based on their respective total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) ferric-reducing power, capacity in nitric oxide, hydroxyl and superoxide radicals scavenging, as well as on their β-glucuronidase, α-glucosidase and α-tyrosinase inhibition activities. H. rhamnoides and C. fistula extracts exhibited similarly high TPC levels, hydroxyl ion [OH•] quenching activity, and α-glucosidase and α-tyrosinase IC50 values (p > 0.05). However, their respective DPPH radical, nitric oxide radical [NO•], and superoxide anion [O2−•] scavenging activities, as well as their IC50 values for β-glucuronidase, significantly differed (p ≤ 0.05), with results showcasing the highest values in C. fistula extracts. In sum, our in vitro data explicitly suggest that the pod extracts of C. fistula exert better antioxidant and enzymatic properties than those exhibited by the fruit extract of H. rhamnoides. They also implicitly encourage performing multiple in vitro assays in order to thoroughly select a plant extract destined to a given medicinal, dietetic, or esthetic application.