bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Influencing the Health and Wellness of Urban Aboriginal Youths in Canada: Insights of In-Service Professionals, Care Providers, and Stakeholders
Authors: Yi Kyoung June , Landais Edwige , Kolahdooz Fariba , Sharma Sangita
Published: March 2015

We addressed the positive and negative factors that influence the health and wellness of urban Aboriginal youths in Canada and ways of restoring, promoting, and maintaining the health and wellness of this population. Fifty-three in-service professionals, care providers, and stakeholders participated in this study in which we employed the Glaserian grounded theory approach. We identified perceived positive and negative factors. Participants suggested 5 approaches—(1) youth based and youth driven, (2) community based and community driven, (3) culturally appropriate, (4) enabling and empowering, and (5) sustainable—as well as some practical strategies for the development and implementation of programs. We have provided empirical knowledge about barriers to and opportunities for improving health and wellness among urban Aboriginal youths in Canada.
Public Health Departments and Accountable Care Organizations: Finding Common Ground in Population Health
Authors: Ingram Richard , Scutchfield F. Douglas , Costich Julia F.
Published: March 2015

We examined areas of potential collaboration between accountable care organizations and public health agencies, as well as perceived barriers and facilitators.

We interviewed 9 key informants on 4 topics: advantages of public health agency involvement in accountable care organizations; services public health agencies could provide; practical, cultural, and legal barriers to accountable care organization–public health agency involvement; and business models that facilitate accountable care organization–public health agency collaboration.

Public health agencies could help accountable care organizations partner with community organizations and reach vulnerable patients, provide population-based services and surveillance data, and promote policies that improve member health. Barriers include accountable care organizations’ need for short-term financial yield, limited public health agency technical and financial capacity, and the absence of a financial model.
Impact of the Garrett Lee Smith Youth Suicide Prevention Program on Suicide Mortality
Authors: Walrath Christine , Garraza Lucas Godoy , Reid Hailey , Goldston David B. , McKeon Richard
Published: March 2015

Objectives: We examined whether a reduction in youth suicide mortality occurred between 2007 and 2010 that could reasonably be attributed to Garrett Lee Smith (GLS) program efforts.

Methods: We compared youth mortality rates across time between counties that implemented GLS-funded gatekeeper training sessions (the most frequently implemented suicide prevention strategy among grantees) and a set of matched counties in which no GLS-funded training occurred. A rich set of background characteristics, including preintervention mortality rates, was accounted for with a combination of propensity score–based techniques. We also analyzed closely related outcomes that we did not expect to be affected by GLS as control outcomes.

Results: Counties implementing GLS training had significantly lower suicide rates among the population aged 10 to 24 years the year after GLS training than similar counties that did not implement GLS training (1.33 fewer deaths per 100 000; P = .02). Simultaneously, we found no significant difference in terms of adult suicide mortality rates or nonsuicide youth mortality the year after the implementation.

Conclusions: These results support the existence of an important reduction in youth suicide rates resulting from the implementation of GLS suicide prevention programming.
Trends in Sexual Orientation Missing Data Over a Decade of the California Health Interview Survey
Authors: Jans Matt , Viana Joseph , Grant David , Cochran Susan D. , Lee Annie C. , Ponce Ninez A.
Published: March 2015

Objectives. We explored changes in sexual orientation question item completion in a large statewide health survey.

Methods. We used 2003 to 2011 California Health Interview Survey data to investigate sexual orientation item nonresponse and sexual minority self-identification trends in a cross-sectional sample representing the noninstitutionalized California household population aged 18 to 70 years (n = 182 812 adults).

Results. Asians, Hispanics, limited-English-proficient respondents, and those interviewed in non-English languages showed the greatest declines in sexual orientation item nonresponse. Asian women, regardless of English-proficiency status, had the highest odds of item nonresponse. Spanish interviews produced more nonresponse than English interviews and Asian-language interviews produced less nonresponse when we controlled for demographic factors and survey cycle. Sexual minority self-identification increased in concert with the item nonresponse decline.

Conclusions. Sexual orientation nonresponse declines and the increase in sexual minority identification suggest greater acceptability of sexual orientation assessment in surveys. Item nonresponse rate convergence among races/ethnicities, language proficiency groups, and interview languages shows that sexual orientation can be measured in surveys of diverse populations.
The Impact of Texting Bans on Motor Vehicle Crash–Related Hospitalizations
Authors: Ferdinand Alva O. , Menachemi Nir , Blackburn Justin L. , Sen Bisakha , Nelson Leonard , Morrisey Michael
Published: March 2015

We used a panel design and the Nationwide Inpatient Sample from 19 states between 2003 and 2010 to examine the impact of texting bans on crash-related hospitalizations. We conducted conditional negative binomial regressions with state, year, and month fixed effects to examine changes in crash-related hospitalizations in states after the enactment of a texting ban relative to those in states without such bans.

Results indicate that texting bans were associated with a 7% reduction in crash-related hospitalizations among all age groups. Texting bans were significantly associated with reductions in hospitalizations among those aged 22 to 64 years and those aged 65 years or older. Marginal reductions were seen among adolescents.

States that have not passed strict texting bans should consider doing so.
A Comparison of Liver Disease Mortality With HIV and Overdose Mortality Among Georgia Prisoners and Releasees: A 2-Decade Cohort Study of Prisoners Incarcerated in 1991
Authors: Spaulding Anne C. , Sharma Akshay , Messina Lauren C. , Zlotorzynska Maria , Miller Lesley , Binswanger Ingrid A.
Published: March 2015

Objectives. We investigated whether eventual causes of death among a cohort of inmates imprisoned in the southeastern United States differed from those in previous prisoner studies.

Methods. We matched 23 510 prisoners in Georgia, a state with historically low levels of heroin consumption but moderate amounts of injection drug use, who were incarcerated on June 30, 1991, to death registries through 2010. Main exposure was 4-year time intervals over 2 decades of observation; main outcome was mortality from liver disease, HIV, and overdose.

Results. Although the HIV-related mortality rate exceeded that from liver-related conditions before 2003, liver disease subsequently surpassed HIV as a cause of death. Among 3863 deaths, 22 (0.6%) occurred within 2 weeks after release from prison. Of these, only 2 were caused by accidental poisoning (likely drug overdose). Cardiovascular disease and cancer were the most frequent causes of death in this aging cohort.

Conclusions. Our study design deemphasized immediate deaths but highlighted long-term sequelae of exposure to viral hepatitis and alcohol. Treating hepatitis C and implementing interventions to manage alcohol use disorders may improve survival among prisoners in the Southeast.
Predicted Probabilities' Relationship to Inclusion Probabilities
Authors: Fang Di , Chong Jenny , Wilson Jeffrey R.
Published: March 2015

It has been shown that under a general multiplicative intercept model for risk, case-control (retrospective) data can be analyzed by maximum likelihood as if they had arisen prospectively, up to an unknown multiplicative constant, which depends on the relative sampling fraction. 1 With suitable auxiliary information, retrospective data can also be used to estimate response probabilities. 2 In other words, predictive probabilities obtained without adjustments from retrospective data will likely be different from those obtained from prospective data. We highlighted this using binary data from Medicare to determine the probability of readmission into the hospital within 30 days of discharge, which is particularly timely because Medicare has begun penalizing hospitals for certain readmissions. 3
A minimalist model of terminal lakes: Qinghai Lake (China) and Lake Chad (N Africa)
Authors: Fraedrich Klaus
Published: March 2015

The ratio of the areas of a terminal lake to its total basin provides a geomorphological measure, which characterises the geobotanical state of water limited climates. A minimalist model of this lake area ratio is introduced combining the water balances of lake and land, the Budyko–Schreiber rainfall–runoff chain over land and, as a closure, the land and lake potential evaporation to be of similar magnitude. The following results are analysed. (i) Model diagnostics quantify a dryness threshold separating water from energy limited climate regimes, which coincides with an upper bound for the area ratio of terminal lakes to remain hydrologically closed. (ii) Model validations for Qinghai Lake and Lake Chad demonstrate model and observed water flux budgets to be in close agreement. (iii) Finally, a paleo-climate sensitivity study for Lake Chad demonstrates that the minimalist model appears to be a viable tool for future and paleo-climate estimates based on lake area ratio changes only and a single reference water flux. Furthermore, a stochastic interpretation of the rainfall–runoff chain allows estimates of water flux variability.
Hysteresis effects of suspended sediment transport in relation to geomorphic conditions and dominant sediment sources in medium and large rivers of the Russian Arctic
Authors: Tananaev Nikita I.
Published: March 2015

Preliminary analysis of long-term hydrological data shows that sediment dynamics of Russian Arctic rivers is largely affected by hysteresis effects in relation of water discharge to suspended sediment concentration (SSC). The role of large-scale geomorphic and geocryological conditions in sediment transport is still relatively understudied. This research aims to assess the links between hydrogeomorphology and regularities of sediment formation and movement in Russian Arctic rivers. A dataset containing information on measured water discharges and SSC for 27 gauges on 16 medium and large rivers of the Russian Arctic was used in this research. Clockwise hysteresis is typical during spring events, while in summer counterclockwise and ‘figure eight’ curves are widely observed. The results show that the form of the rating curve can be attributed to the dominant sediment source, dominant channel pattern and, to certain extent, to the cross-section position within the river basin. Seasonality in hysteresis effects reflects the role frozen ground dynamic plays in sediment flux formation. Thus, reaction of permafrost landscapes on the widely observed climate shift should lead to significant changes in sediment transfer systems.
Editorial: Hydrogeomorphology – a long-term scientific interface
Authors: Cudennec Christophe , de Lavenne Alban
Published: March 2015

Hydrogeomorphology is reframed as an old inter-discipline, which is still highly relevant to both hydrology and geomorphology, renewed by new techniques and new questions in line with challenges of ungauged basins; anthropogenic changes in driving forces, landscape structures, and dynamic functions; translation of science into practice; and retrospective and prospective analyses. The corpus and experience of hydrogeomorphology are also highlighted regarding new emerging sub- or inter-disciplines, in terms of epistemic bridging and dealing with complexity.
The Method of Design Sine Grating Based on Optimal PWM
Authors: Fu Qiao
Published: March 2015

In the structured light 3d optical measurement field, the sinusoidal grating design is one of the research focus.
The traditional focus methods of generating sine pattern can’t be widely accepted because of many well known defects.
While the another traditional binary pattern generated from Ronchi grating which need defocusing processing, its
application has also been a certain limit because of its projected pattern contrast ratio is not high.In this paper, we have
proposed a designing sine grating method with the spatial modulation theory based on Optimal PWM in electronic
engineering. Compared with Ronchi grating, this method of generating pattern have better fringe contrast, and more
simple defocusing requirements, so this method have good practical economic value.
Study on Battery Fast Charge and Discharge Model and its Parameters
Authors: Chen Lun-qiong , Du Lu-lu , Li Bei
Published: March 2015

In order to study the battery performance, putting forward a kind of two order RC equivalent circuit model,
measuring static and transient data by HPPC test, fitting the relationship between open circuit voltage and state of
charge (SOC), analyzing system identification of the dynamic parameters with MATLAB tool. Finally, by comparing the
simulation data with the test data, the model is correct and feasible.
Association of High Blood Pressure with Body Mass Index, Smoking and Physical Activity in Healthy Young Adults
Authors: Papathanasiou George , Zerva Efthimia , Zacharis Ioannis , Papandreou Maria , Papageorgiou Effie , Tzima Christina , Georgakopoulos Dimitris , Evangelou Angelos
Published: March 2015

Introduction:

The purpose of this study was to examine the associations between resting blood pressure (BP), smoking, physical activity (PA) and body mass index (BMI) in Greek young adults.

Materials and Methodology:

A standardised questionnaire and the Greek version of IPAQ-short were given to 1500 randomly selected health science students, in order to record smoking behaviour, PA status, BMI and resting BP. All healthy young adults aged 19-30 years old were eligible. The final size of the study cohort was 1249 students (522 men).

Results:

Males’ BP was 129.2/77.0 mmHg, significantly higher than the females’ values of 119.9/73.4 mmHg. Approximately 17% of the total population were classified as overweight and 3% as obese. In the overall population, smoking prevalence was 35.2%, with 15.3% being heavy smokers (≥21 cigs/d). Smoking prevalence did not differ significantly between sexes. The prevalence of health-enhancing PA (high PAclass) was only 14.0%, while 42.8% of the study population were classified as insufficiently active (low PAclass). Of the three lifestyle risk factors examined, only BMI was significantly and directly associated with systolic and diastolic BP levels. The prevalence of hypertension (≥140/90 mmHg) was significantly higher in men compared to women, and in obese and overweight participants compared to normal-weight subjects. Smoking and categorical PA (PAclass) were not correlated with BP. Continuous vigorous PAscore was significantly and directly associated with systolic BP, but only in males.

Conclusion:

BMI was significantly and directly associated with resting BP in both sexes. Smoking prevalence and PA status were not associated with BP in this sample of Greek young adults.
A Novel Analytical Curve for Forecasting and Monitoring Gasflood
Performance
Authors: Tong Kaijun , Ge Lizhen , Shi Fei , Zhu Zhiqiang , Nie Lingling
Published: March 2015

With the increasing proportion of gas cap & artificial gas injection reservoirs, production performance monitoring
and evaluation of gas-drive reservoir are becoming more and more important. However, there is no efficient method to
forecast the production performance of gas-drive reservoir. In this paper, the analysis starts from the statistics of oil/gas
relative permeability data of cores experiments. Based on fundamental principles of segregated flow and material balance,
a new analytical curve of gasflood was developed to analyze the production performance. We applied the novel analytical
curve to the production data from 23 gas-drive reservoirs at home and abroad and found a better power function relationship
between dynamic reserves (N) and the slope (B) as foreseen by the analytical curve. It has been shown that the slope
of the new curve represents dynamic reserves value; the smaller the slope value is, the more dynamic reserves are. Furthermore,
by introducing the economic limit gas-oil ratio and control conditions which include initial and boundary conditions,
a chart of dimensionless fractional flow of gas vs. recovery percent of OOIP is established to evaluate oilfield development
rapidly and intuitively. Finally, many examples of application confirmed strongly that the new analytical curve
used in gas-drive reservoirs is practical and effective, which broadens the scope of gas-drive oilfield research.
Scientific Laboratory Platform for Testing the Electric Vehicle Equipped with DC Drive
Authors: Brazis V. , Kroics K. , Grigans L.
Published: March 2015

The authors present a test platform for the low-power DC electric motor of a traction vehicle or a high-power motor scaled in the traction and braking modes. The load emulator of the traction drive is made using an induction motor controlled by a frequency converter. A microcontroller controls the bi-directional DC/DC converter and sends a speed reference signal to the frequency converter. The test bench is meant for determination of the power consumption by motor in various speed cycles, and will be used to demonstrate the operation of electric vehicle to students and to investigate the charging/discharging strategies of energy sources.
Serum concentration of haptoglobin in European mouflon (Ovis musimon L.) from a game reserve
Authors: Smitka Peter , Tóthová Csilla , Čurlík Ján , Lazar Peter , Bíreš Jozef , Pošiváková Terézia
Published: March 2015

Acute phase proteins are used as markers of inflammation and sub-clinical disease, and are considered potential biomarkers for animal health and welfare. The objective of this study was to analyse haptoglobin as the main positive acute phase protein in the mouflon. A total of 30 clinically healthy mouflon of different age and sex, reared in a game reserve, were used for this study. Haptoglobin was determined in blood serum by colorimetric assay with a commercially accessible kit. The mean value of haptoglobin in the herd was 0.215 ± 0.068 mg/ml. There was no significant difference between animals divided by sex: male 0.228 ± 0.073 mg/ml, female 0.202 ± 0.062 mg/ml. The mean value in young animals was higher than the mean value in the adults 0.260 ± 0.081 mg/ml and 0.201 ± 0.059 mg/ml, respectively (P < 0.05). This work was designed to identify the baseline concentration of haptoglobin in a clinically healthy population, thus allowing the comparison of welfare and general health status of the herds or different structured groups within the game reserve. This is the first similar study of haptoglobin as a biomarker in the mouflon.
Comparative data concerning aflatoxin contents in Bt maize and non-Bt isogenic maize in relation to human and animal health – a review
Authors: Ostrý Vladimír , Malíř František , Pfohl-Leszkowicz Annie
Published: March 2015

Transgenic Bt maize is a potentially important tool against insect pest in the EU and other countries. Bt maize (e.g. MON 810, Bt 11) which carries the Bt gene is highly resistant to larval feeding of European corn borer, stalk borer, and Southwestern corn borer, depending on Bt toxin (δ toxin) production. Effective measures used to fight pests may often have positive side-effects in that they may also contribute to reducing mycotoxin concentrations. A systematic review has been used for the purposes of evaluating the studies on the reduction of aflatoxins in Bt maize. According to five studies, Bt maize has significantly lower concentrations of aflatoxins than non-Bt maize hybrids, only one study has shown no significant effect of Bt maize. Other studies have shown mixed results (four studies). The results of these studies were influenced by the year of sampling or by using maize breeding lines selected for resistance to aflatoxin accumulation.
Combination of lidocaine/prilocaine with tramadol for short time anaesthesia-analgesia in chelonians: 18 cases
Authors: Spadola Filippo , Morici Manuel , Knotek Zdeněk
Published: March 2015

The aim of this study was the evaluation of the practical use of lidocaine/prilocaine cream as the local anaesthetic in combination with tramadol anaesthesia for the surgical treatment of prolapsed penis in chelonians. Eighteen animals were included in this study. After administration of tramadol, prolapsed penis was cleaned and disinfected. Lidocaine/prilocaine cream at a dose of 1g/10 cm2 was applied on the penile mucosa. The time interval from lidocaine/prilocaine application to a loss of hind limb withdrawal reflex and the response to penile mucosa pinching was recorded as the induction time for surgical anaesthesia. The time interval from lidocaine/prilocaine application to full restoration of tail and hind limb withdrawal reflex was recorded as the recovery time. In two male chelonians the response to pain stimuli persisted for more than 20 min after lidocaine/prilocaine cream application, and the anaesthetic cream had to be re-administered. After this second application of lidocaine/prilocaine cream, surgical anaesthesia was reached within 28 and 32 min. The mean induction time for surgical anaesthesia was 19.22 ± 4.36 min. The mean recovery time was 40.83 ± 7.68 min. In all 18 male chelonians the surgical treatment of prolapsed penile was uneventful. Topical application of lidocaine/prilocaine cream can be used as a feasible form of local anaesthesia in combination with tramadol analgesia management for minor surgical procedures in chelonians.
Risk factors for TB and HIV coinfection in Scotland, 2001 to 2010
Authors: McDonald E , Smith-Palmer Alison , Wallace L A , Blatchford O
Published: March 2015

The number of patients with tuberculosis (TB) increased steadily in Scotland between 2005 and 2010. Human immunodeficiency virus (HIV) infection has been a contributory factor to increases in TB in a number of comparable industrialised countries. This study investigated the extent of, and risk factors for, TB and HIV coinfection in Scotland from 2001 to 2010. Patients with TB in the national TB database were linked to those in the national HIV database using probabilistic data linkage. Patient records were anonymised to maintain confidentiality. From 2001 to 2010, 106/4,097 (2.6%, 95% CI: 2.1 to 3.1) TB patients matched with HIV patients, equating to a 10-year incidence of 2.1 cases per million population. Patients with both TB and HIV were more often born outside the United Kingdom, were of black African ethnicity, had refugee status and had extra-thoracic lymph node involvement or cryptic/disseminated TB disease. Individuals with TB and HIV coinfection were younger and symptomatic for a shorter time before their diagnosis of TB, compared with TB patients without HIV. TB and HIV coinfection was relatively uncommon in Scotland in the study period. Clinicians should recognise the potential for HIV infection among TB patients and the importance of offering an HIV test to all TB patients.
Study of metabolic syndrome in postmenopausal women
Authors: Sapkota Alina Shri , Sapkota Alisha , Acharya Kamananda , Raut Mithileshwer , Jha Bharat
Published: March 2015

BACKGROUND: Various studies throughout the world have documented higher prevalence of Metabolic Syndrome (MS) and CV risk factors in postmenopausal women. Abdominal obesity, a key component of metabolic syndrome is quite prevalent in South Asian women. However, studies that have investigated the effect of menopause on the health status of Nepalese women is lacking. METHODS: This cross-sectional study was conducted in TUTH, Kathmandu Nepal. Forty five each premenopausal and postmenopausal (defined by cessation of menstruation for ≥12 months) women visiting the General Health Checkup Unit were enrolled as participants. Metabolic syndrome was defined by IDF criteria. BP, height, weight and WC were measured and BMI was calculated while fasting blood samples were analyzed for serum biochemical markers: FBG, lipid profile. RESULTS: This study found higher prevalence of MS in postmenopausal women (57.8%) in comparison to premenopausal women (20%). 13.3% were diabetic, 23.3% were hypertensive, 82.2% had abdominal obesity (WC>80 cm), 43.3% were overweight (BMI 25-29.99 Kg/m2) and 13.3 % were obese (BMI≥30 Kg/m2). WC, BMI and SBP were significantly higher in postmenopausal group. Among the biochemical markers, FBG, TC, LDL-C, TG were significantly higher whereas HDL-C was significantly lower in postmenopausal women than in premenopausal women. CONCLUSION: MS was highly prevalent in postmenopausal women. This is an indication of taking necessary preventive measures so that the risk of developing diabetes and cardiovascular disease can be minimized in the postmenopausal group. DOI: http://dx.doi.org/10.3126/acclm.v1i1.12307 Ann. Clin. Chem. & Lab. Med. 1(1) 2015: 6-11
Spectrum of acute leukemias diagnosed on flow cytometry: Analysis from tertiary care centre from North India
Authors: Koju Surendra , Sachdeva Man Updesh Singh , Bose Praveen , Varma Neelam
Published: March 2015

BACKGROUND: Acute leukemias (ALs) are a heterogeneous group of malignancies with varying clinical, morphologic, immunologic, and molecular characteristics. WHO 2008 classification of ALs require a multi-parametric approach to the diagnosis. This study aims to evaluate the role of flow cytometry in diagnosis and sub-classification of acute leukemias. METHODS: Consecutive patients of adult and paediatric ALs during June 2012 to May 2013 were retrospectively analyzed and studied using BD FACS Canto-II flow cytometer. The results of immunophenotyping were reviewed and analyzed for cross-lineage antigen expression. RESULT: Over a period of year, 422 individuals were diagnosed as AL. There were 287 males and 135 females with M:F = 2.1:1. There were 237 adults & 185 children. 36.3% were AML and 60.4% were ALL, while 3.3% of cases were mixed phenotypic acute leukemia (MPAL). The commonest WHO subtype in AML group was AML with maturation being 31%. In case of ALL there were 83.9% B-ALLs and 16.1% T-ALLs. In MPAL B-Myeloid was 71.4%, whereas T-Myeloid was 28.6% of cases. Both AML and MPAL were more frequently seen in adults accounting to 83% and 92.9% respectively of all ALs cases. In contrast, 62% of ALLs were children and only 38% were adults. Out of all ALs, 37.6% of showed cross lineage antigen expression. In AML, B-ALL and T-ALL cross lineage antigen expression were 26.14%, 39.71% and 82.9% respectively. CONCLUSION: Flow cytometry is useful in diagnosis and sub classification of AL. It is essential in cytochemical myeloperoxidase (MPO) negative cases. Cross- lineage antigen expression is frequent in ALs, and hence, lineage specific intra-cytoplasmic antibodies including anti-MPO and cytoplasmic-CD3 are essential for correct categorization of ALs. DOI: http://dx.doi.org/10.3126/acclm.v1i1.12308 Ann. Clin. Chem. & Lab. Med. 1(1) 2015: 12-15
Short-Term Freeway Speed Profiling Based on Longitudinal Spatiotemporal Dynamics
Authors: Yang Jianjiang , Han Lee D. , Freeze Phillip B. , Chin Shih-Miao , Hwang Ho-Ling
Published: March 2015

Short-term traffic forecasting accuracy is related closely to the use of neighboring traffic information. Multivariate forecasting methods are becoming more popular because of their ability to capture both temporal and spatial evolvement in traffic. However, little attention has been given to quantify the effect of upstream and downstream traffic information, and the vast majority of published studies assume that the spatiotemporal relationship is specified in advance. Thus, the selection of surrounding traffic information as input parameters is somewhat arbitrary. To address that issue, this study investigated spatiotemporal relationships of speed series from consecutive segments under different traffic conditions by using the link speeds for nine segments extending over 12 mi on I-24 in Nashville, Tennessee. A prewhitened cross-correlation technique was proposed first to clarify the cross correlations between two speed series. The prewhitened cross-correlation function was performed on speed series for consecutive freeway segments for periods including the morning peak, midday off-peak, and evening peak. The analysis results showed that the correlations for consecutive segments were highly related to traffic conditions and that the effect of downstream traffic increased with the severity of congestion. Influences of upstream and downstream locations on current traffic were also found to be not symmetric in regard to the current site. The algorithm on properly choosing neighboring traffic information was proposed, and the lagged regression model with correctly identified input parameters (segments) outperformed others.
Algorithm for Determining Path of Maximum Reliability on a Network Subject to Random Arc Connectivity Failures
Authors: Seshadri Ravi , Srinivasan Karthik K.
Published: March 2015

Several types of infrastructure networks such as transportation, utility, and pipeline systems may be subject to severe damage from exposure to human-caused and natural disasters (hurricanes, floods, earthquakes, etc.). Assessing the capability of a transportation network to provide basic functionality following catastrophic events involves estimating whether adequate connectivity can be ensured. In that context, this paper addresses the problem of identifying the path of maximum connectivity reliability between a pair of origin and destination nodes on a network subject to random and correlated arc connectivity failures. In view of the failure of the subpath optimality property for this maximum connectivity reliability problem, a reliability bounds–based sufficient condition for optimality is established. Based on this principle, a proposed algorithm estimates the reliability bounds by means of a candidate path set computed by using an efficient K shortest path algorithm. In the absence of convergence of the reliability bounds, an iterative gap reduction procedure is proposed to combine Monte Carlo simulation and network optimization to improve the lower bound by generating additional candidate paths. The proposed gap reduction and reliability evaluation procedures use a stochastic decomposition of the link failure propensity to improve computational efficiency. Empirical experiments on realistically sized synthetic networks show the proposed algorithm to be efficient and requiring limited path enumeration, and the experiments underscore the importance of modeling the correlations in link failures.
Integrated Planning of Tourism Investment and Transportation Network Design
Authors: Bai Yun , Kou Xiaofeng , An Shi , Ouyang Yanfeng , Wang Jian , Zhu Xiaoying
Published: March 2015

The development of a viable and sustainable tourism industry requires wise strategic planning of investments in tourism sites and the supporting transportation infrastructure. In view of the interactive relationship between transportation and the tourism industry, this paper proposes an integrated modeling framework to address tourism planning and transportation network design simultaneously. A bilevel optimization model was proposed to decide the optimal locations for tourism investment and highway capacity expansion. The upper-level problem minimized the total system cost while the lower-level model determined user equilibrium flow of tourist and nontourist road users under traffic congestion. A customized solution approach based on relaxation, reformulation, and approximation was developed. The proposed methodology was applied to an empirical case study for Heilongjiang Province, China, to show implications of the optimal strategies for tourism planning.
Community Rideshare for a Small City
Authors: O'Brien J. , Dunning A.
Published: March 2015

Empty seats in private vehicles move across regions over a large service area at a high frequency. Decades of publicity campaigns have denounced hitchhiking as dangerous despite a lack of objective evidence that indicated increased security risks. Even so, drivers in and around the small metropolis of Lawrence, Kansas, demonstrated that they were willing to share their empty seats with people who used the Lawrence OnBoard rideshare system, which had its basis in hitchhiking. Lawrence OnBoard gathered data on 121 rides in initial system trials, interviewed 18 riders, and solicited mail-in surveys from participating drivers. For more than half of the 121 trips, riders waited fewer than 5 min on the roadside before someone provided a ride. Two important factors that contributed to the quick pickups were the rider's choice of pickup location and a clear declaration of desired destination presented on an official-looking ride board. The 5% of trip attempts that proved fruitless were quickly remedied by a change in pickup location. Rider interviews indicated that people felt anxiety before a pickup and then felt comfortable with their drivers as long as the vehicle had adequate room and had working seat belts and no one was smoking. Lawrence OnBoard's experience can serve as a possible model to increase rideshare and mobility in cities smaller than the typical major metropolises known for dynamic carpool (or slugging) systems.
Comprehensive Framework for Planning and Assessment of Traffic Incident Management Programs
Authors: Jin Xia , Hossan M. Sakoat , Gan Albert , Chen Dong
Published: March 2015

This paper presents a comprehensive framework for traffic incident management (TIM) covering major components and key elements that contribute to the success of a TIM program. The proposed framework starts with three broad categories of components-strategic, tactical, and support-and then expands with detailed elements that are essential to accomplishing the goals for each component. The strategic component focuses on establishing and promoting institutional, organizational, and financial contexts, and the support component addresses information and communication aspects of TIM. Both components are critical to the performance of the tactical component, which covers the core activities in incident clearance and traffic management. The framework builds on federal guidance for major components and strategies in TIM while adding more structured details and perspectives that serve as the basic guidelines in planning and assessment of TIM programs. The paper also presents a case study that links the Florida Department of Transportation District 4's TIM practices with the framework. The case study can be seen as examples of (best) practices for each subelement of the framework. In addition, this study demonstrates the role of the framework in providing guidance for program planning and assessment.
Design of Emergency Response System to Minimize Incident Impacts
Authors: Kim Hyeonmi , Kim Woon , Chang Gang-Len , Rochon Steve M.
Published: March 2015

Analysis of incident data from the Maryland Highway Administration leads to the conclusion that efficient operations of an incident management team can contribute to reduction in not only response time but also clearance time. This paper presents an integer programming model for optimizing the deployment locations of emergency response units. Unlike models in most existing studies, the proposed model is designed to assign the available units to minimize the total delay caused by incidents rather than to minimize the units’ average response times. By giving more weight to locations likely to have more severe incidents and accounting for the variance in incident duration, the proposed model with incident data from Maryland can outperform both the popular P-median model and state-of-the-practice deployment strategies. Extensive sensitivity analyses with respect to various traffic volumes and incident frequencies have also confirmed the superior performance of the proposed model in minimizing the total delay caused by incidents.
Optimal Control of Motorways by Ramp Metering, Variable Speed Limits, and Hard-Shoulder Running
Authors: Li Ying , Chow Andy H. F. , Cassel Daniela Lichtler
Published: March 2015

Ramp metering, variable speed limits, and hard-shoulder running have been used for managing motorway traffic congestion. The majority of the research in the area of ramp metering strategies is concentrated on local traffic responsive algorithms, such as ALINEA. Recently, researchers have studied the effects of variable speed limits and hard-shoulder running applied on motorways. This paper presents an optimization framework for all these control strategies. The framework was developed on the basis of a macroscopic cell transmission model (CTM), which described traffic dynamics through a piecewise linear fundamental diagram. With the piecewise linear nature of the CTM, the authors formulated optimal control problems that would seek the optimal control policies for minimizing total delays on motorways. The optimal control problems were formulated as linear programming or mixed integer linear programming and were solved by using the IBM CPLEX solver. The performances of different control strategies were tested on real scenarios on the M25 motorway in England, where significant improvements were observed with proper implementation.
Accounting for Travel Time Reliability and Trip Purpose in an Agent-Based Approach to Toll Pricing with Dynamic Feedback Control
Authors: Cheng Danhong , Li Wan , Ishak Sherif
Published: March 2015

Congestion pricing is an effective management policy to reduce traffic congestion on freeways. This study accounted for the travel time difference and reliability on managed and general-purpose lanes in a modified approach to determining toll rates recently developed by others. The original approach was modified by developing an agent-based toll pricing strategy that used dynamic feedback control and accounted for trip purpose, travel time reliability (TTR), and level of income to maximize toll revenue while maintaining a minimum desired level of service on managed lanes. An external module was developed to execute the modified strategy in VISSIM, which exported the traffic data generated to an Excel spreadsheet in real time to calculate TTR, used in the route choice process. Agent-based modeling simulated drivers’ learning process and estimation of TTR from their previous commuting experience. A numerical example illustrated the modified strategy. The simulation results confirmed that, under high traffic demand, drivers with an urgent trip purpose had the highest probability of choosing managed lanes and that travel time on those lanes was more reliable than on general-purpose lanes. The modified strategy, the strategy currently deployed on I-95 express lanes, and the original strategy were compared. The modified one had a steadier increase in toll rate, significantly higher toll revenue, and speeds higher than 45 mph more frequently, compared with the current strategy. Furthermore, the modified approach was more realistic, accounted for TTR in route choice, and generated higher toll revenue under heavy traffic demand than did the original strategy.
Collection, Screening, and Evaluation of Vehicle Occupancy Data
Authors: Elango Vetri Venthan , Guensler Randall
Published: March 2015

In 2008, the Georgia State Road and Tollway Authority and the Georgia Department of Transportation successfully applied to the U.S. Department of Transportation for seed funding under the Congestion Reduction Demonstration Program Grant to convert the congested I-85 high-occupancy-vehicle (HOV) lane to a high-occupancy-toll (HOT) lane. The facility was converted into a HOT lane and opened on October 1, 2011. This paper reports on the collection, processing, and filtering of the vehicle occupancy data and the factors that influenced vehicle occupancy along the I-85 corridor both before and after the conversion. The research effort used regression tree analysis techniques to identify data collector bias and then the effects of different factors such as season, data collection site, morning peak–evening peak, and lane type on vehicle occupancy. The study found that vehicle occupancy data on Monday were different from those data collected on Tuesdays, Wednesdays, and Thursdays. The study identified data collectors and sessions that had statistically different data from other sessions and filtered those data. The research effort then explored the factors affecting vehicle occupancy for the morning peak and the afternoon peak periods separately, given that related travel behavior characteristics were quite different. The research identified lane type (managed or general-purpose) as the most significant factor affecting occupancy, followed by pre- and postconversion of the HOV lane to HOT lane. The study also found that average vehicle occupancy decreased after conversion of the HOV lane. On the basis of the results of this study, the vehicle occupancy data were aggregated into the center stations, north of the GA-316 region and south of the I-285 region. The vehicle occupancy data are currently being applied to evaluate person throughput along the corridor.
Can Psychological Questions Help Predict Managed Lane Use?
Authors: Green Lisa L. , Burris Mark W.
Published: March 2015

Managed lanes (MLs) are being used in many congested cities across the United States. While the socioeconomic characteristics of travelers, along with their trip characteristics, are commonly used to model ML choice behavior, other variables—such as psychological characteristics of travelers—may be beneficial in improving the understanding of travel behavior on MLs. Preliminary research on this possibility collected psychological data from ML users and determined that, in their psychological-construct form, psychological traits provided little benefit in creating models that accurately predicted ML use. This paper uses those data to consider further their impact on discrete choice modeling when individual psychological variables are considered in a more disaggregate fashion, thus helping to uncover the information that may be masked when these data are considered only in the psychological-construct form. Among the important conclusions are that some of the psychological questions, working in tandem with typical socioeconomic and trip characteristic variables, indeed appear to contribute to the creation of improved models of ML choice. Specifically, questions taken from the constructs measuring (a) the personal need for structure and (b) driving risk perceptions and driving style appear most promising. The questions highlighted in this paper provide direction for development of psychological questions within the transportation framework.
Value of Travel Time Savings
Authors: Sheikh Adnan , Guin Angshuman , Guensler Randall
Published: March 2015

The I-85 express lanes in the Atlanta, Georgia, metropolitan region are among the newest high-occupancy-toll (HOT) facilities in the United States. This paper examines travelers’ value of time and their willingness to pay for the I-85 express lanes, compares travel times and travel time reliability in the general purpose and HOT lanes, and discusses the benefits users gain from the facility. The study examined 9 months of toll and travel time data for drivers who traversed the entire length of the express lane corridor during the morning and afternoon peak periods. Median values of travel time savings were $36/h in the southbound morning peak period and $26/h in the northbound afternoon peak period. The express lanes exhibited reliability benefits relative to the general-purpose lanes, but this study does not quantify the value of those benefits because of the lack of stated-preference data. The value that HOT lane users attributed to their time saved exceeded the time value obtained by using the average wage rate in the region. These results for the value of travel time were found to be similar to those for HOT lane implementations in other locations.
Greenland high-elevation mass balance: inference and implication of reference period (1961–90) imbalance
Authors: Colgan William , Box Jason E. , Andersen Morten L. , Fettweis Xavier , Csathó Beáta , Fausto Robert S. , Van As Dirk , Wahr John
Published: March 2015

We revisit the input–output mass budget of the high-elevation region of the Greenland ice sheet evaluated by the Program for Arctic Regional Climate Assessment (PARCA). Our revised reference period (1961–90) mass balance of 54±48 Gt a–1 is substantially greater than the 0±21 Gt a–1 assessed by PARCA, but consistent with a recent, fully independent, input–output estimate of high-elevation mass balance (41±61 Gt a–1). Together these estimates infer a reference period high-elevation specific mass balance of 4.8±5.4 cm w.e. a–1. The probability density function (PDF) associated with this combined input–output estimate infers an 81% likelihood of high-elevation specific mass balance being positive (>0 cm w.e. a–1) during the reference period, and a 70% likelihood that specific balance was >2 cm w.e. a–1. Given that reference period accumulation is characteristic of centurial and millennial means, and that in situ mass-balance observations exhibit a dependence on surface slope rather than surface mass balance, we suggest that millennial-scale ice dynamics are the primary driver of subtle reference period high-elevation mass gain. Failure to acknowledge subtle reference period dynamic mass gain can result in underestimating recent dynamic mass loss by ~17%, and recent total Greenland mass loss by ~7%.
Multi-method monitoring of Glacier d’Argentière dynamics
Authors: Benoit Lionel , Dehecq Amaury , Pham Ha-Thai , Vernier Flavien , Trouvé Emmanuel , Moreau Luc , Martin Olivier , Thom Christian , Pierrot-Deseilligny Marc , Briole Pierre
Published: March 2015

The flow of Glacier d’Argentière, French Alps, has been extensively studied by glaciologists for >100 years, but high-temporal- and high-spatial-resolution monitoring of its dynamics has rarely been carried out. In this paper, the terminal part of the main glacier was selected to undertake such a survey. The 2 month experiment (September–November 2013) included remote sensing to map the velocity field of the whole area, and a network of in situ measurements to record the ice velocity at the surface as well as at the base of the glacier with high precision and at high temporal resolution. These monitoring methods are combined to produce a comprehensive and reliable picture of the ice flow. Basal and surface in situ measurements are used to precisely monitor the temporal variability of the ice flow at a section of the glacier where crevassed areas and non-cracked ice coexist. The achieved results are an innovative and efficient tool to investigate the acceleration/deceleration pattern heterogeneities in ice flow that occur after heavy rainfall.