bluuebunny/crossref_metadata_2025 huggingface dataset:
Active Transit Signal Priority for Streetcars
Authors: Currie Graham , Shalaby Amer
Published: August 2008

Although streetcar systems benefit from a strong identity, they face considerable challenges as a result of mixed traffic operations. These problems have been compounded by growing urban auto traffic, which has increased competition for limited road space and time. Active traffic signal priority (TSP) has been identified as a cost-effective way to improve the management of manage traffic systems to make on-street public transport more reliable, faster, and more cost-effective. Although the implementation of TSP is growing throughout the world, relatively few studies have examined its application to streetcar-based systems. This paper reviews the experience with TSP in Melbourne, Australia, and Toronto, Canada. These cities run some of the world's oldest and largest streetcar-based TSP systems. This paper describes the TSP systems adopted in the two cities, including key experiences. TSP performance is reviewed, and identified problems and issues are assessed. The review established that the TSP systems in the two cities have many similarities including the configuration of approach and request loop and stop line and cancel loop detection, the degree of priority provided, and the targeting of clearance phases for turning traffic at intersections. There are some slight differences in the handling of bunching trams and opposing tram movements, which are better handled in the Toronto case. The two systems see rather different futures for TSP development. Toronto is focused on full systemwide TSP implementation and advancement of TSP algorithms, whereas Melbourne aims to make priority more conditional on the degree of lateness of trams and on the degree of traffic congestion experienced.
Successful Historic Streetcar Service
Authors: Osborne Jamie , Newmark Gregory L.
Published: August 2008

San Francisco, California, is closely associated with the operation of historic streetcars. Typically, this association is tied to the cable car; however, during the past two decades, the San Francisco Municipal Railway (Muni) has also become the nation's largest operator of historic streetcars through its F-Market and Wharves line. To assist the many cities interested in creating their own historic streetcar services, this research presents the history of the creation of this unique service, the first quantitative analysis of its operating and ridership characteristics, and a qualitative consideration of the contextual factors supportive of developing a historic streetcar service. The quantitative analysis is based on data collected as part of Muni's Transit Effectiveness Project and argues that the F line has been successful at attracting ridership, particularly in comparison with the rest of Muni's rail services, but does so at a high cost per user and with relatively low utilization of transit capacity. This finding suggests that efforts should be made to improve the efficiency of this service. The qualitative analysis is based on nonprofit publications, newspaper articles, and personal interviews. This analysis identifies a transit-friendly natural and built environment, broad existing transit agency capacity, and active public support for rail transit as key factors conducive to the development of historic streetcar service.
Light Rail Cost Functions and Technical Inefficiency
Authors: Harmatuck Donald J.
Published: August 2008

Light rail operating costs vary with a system's scale of operations, traffic density, vehicle and passenger outputs, and input prices. Previous attempts at estimating these cost relationships have been hampered by inadequate data and methodologies that restrict their functional forms, limit their output measures, omit factor prices, and fail to account for technical inefficiencies. With more data now available from an increased number of systems operating during longer time periods, new cost specifications that improve the precision and reduce the bias of cost estimates can be estimated. Here, light rail cost functions are estimated with 1994 to 2005 data for 21 U.S. light rail systems. The cost functions relate operating and maintenance costs to passenger and vehicle outputs, input prices, route densities, vehicle capacities, and latent cost inefficiencies. Four estimation methods are used: (a) iterative seemingly unrelated regression, (b) least-squares dummy variable, (c) maximum likelihood stochastic frontier, and (d) hierarchical Bayesian frontier models. Economies of size and density, input productivities, input substitution elasticities, and transit system inefficiencies are measured.
Boarding and Alighting Experiments
Authors: Daamen Winnie , Lee Yu-chen , Wiggenraad Paul
Published: August 2008

Vehicle dwell time is an important determinant of the system performance and passenger service quality of public transport systems. Adequate prediction models for vehicle dwell time are required in timetable planning and in pedestrian simulation tools to optimize station design and rolling stock design. Because most of the dwell time is consumed by boarding and alighting, this paper focuses on increasing insight into boarding and alighting behavior in railroad vehicles by performing laboratory experiments using video cameras. The experiments test the effects of the physical environment (stepping gap, height difference, and door width), population (age, gender), flow composition (direction, time pressure, luggage, boarding group size, boarding ratio, queuing discipline), and prevailing traffic conditions (crowding on board and crowding on the platform). From the video images, pedestrian trajectories (movements over time) have been derived. This paper describes the effects of the size of the horizontal and vertical gap and the presence of luggage on the door capacity. Door capacities have been estimated by using headway distributions and cumulative curves. Increasing the horizontal and vertical gap leads to decreases in the capacity (up to 15%). When passengers with luggage (suitcases) are present, the capacity decreases more (up to 25%).
Service Orientation, Bus–Rail Service Integration, and Transit Performance
Authors: Brown Jeffrey R. , Thompson Gregory L.
Published: August 2008

Service orientation is one of the most important decisions that a transit manager makes. A manager can concentrate service on the central business district (CBD) or disperse service to connect multiple destinations. Conventional wisdom suggests that transit managers should focus on serving the CBD, because that—such wisdom suggests—is where riders wish to travel. In some places, the service orientation decision is complicated by the need to define the specific role to be played by rail service. Some managers may view rail transit as part of an integrated network structure. Other managers may view it simply as the functional equivalent of a high-capacity bus route. This research examines the relationship between service orientation, bus–rail service integration, and transit performance in U.S. metropolitan areas with between 1 million and 5 million people. Metropolitan areas that have integrated their rail transit into a decentralized network structure are found to enjoy higher riding habit, higher service productivity, and better cost-effectiveness than metropolitan areas with other network structures or modal combinations. These findings suggest the need for transit managers to carefully consider the relationship between service orientation and bus–rail integration to better serve their customers and improve overall transit performance.
Commuter Rail Circulator Route Network Design and Its Implications for Transit Accessibility
Authors: Lownes Nicholas E. , Machemehl Randy B.
Published: August 2008

The success of a commuter rail system depends on cultivating a ridership base on which to expand the system. Cultivating this ridership depends on offering a quality transportation option to commuters. Characteristics of commuter rail systems in the United States present significant challenges. Commuter rail has been implemented only on existing rail right-of-way (ROW) and infrastructure in the United States. Existing rail ROW does not often coincide with current commercial and residential demand centers and necessitates the use of a circulator system to improve the accessibility of the system. The commuter rail circulator network design problem (CRCNDP) addresses a particular aspect of the commuter rail trip, seeking to improve the performance of the entire system through accurately modeling the portion of the trip from rail station to the final destination. This final leg includes the trip on the circulator vehicle and the walking trip from the circulator stop to the final destination. A detailed description of the CRCNDP is provided, as well as a case study that will seek to illuminate the performance of the CRCNDP using three operational strategies.
New-Generation Personal Rapid Transit Technologies
Authors: Cottrell Wayne D. , Mikosza Ollie
Published: August 2008

An overview and a comparison of several new-generation personal rapid transit (PRT) technologies are provided. A total of about 40 known PRT concepts existed as of 2007, of which 19 were being actively developed (i.e., not dormant, with some testing completed). Of the 19, 10 had readily accessible operational specifications, enabling an assessment and comparison. Ten operational parameters were considered for each of the technologies. A throughput of 7,200 passengers per hour on a single-track PRT line is possible with a minimum headway of 1.0 s, line speed of 35 km/h, and braking rate of 9.8 m/s2 (i.e., Gx). A minimum headway of 0.5 s is possible either at low speeds (<20 km/h) or with hard emergency braking (≥2Gx). PRT technologies proposing values that exceed these limits may not be feasible. To accommodate short headways and high emergency braking rates, controls that require seated passengers should be considered. Only Urban Light Transport and Vectus feature a full slate of either feasible or fundamental (i.e., preferable) operating characteristics. CyberCab and MISTER would be more feasible with decreases in minimum headway and line speed, respectively. The other technologies are partially feasible, unclear in terms of certain characteristics, or better classified as “high-speed” PRT. The findings may facilitate the formulation of PRT standards and operating criteria. These, along with a successful implementation of PRT at Heathrow Airport in England, may generate new markets and competitive technologies. Further studies comparing guideway design, materials, switching, station design, visual impacts, costs, and financing are needed.
Breeding for Slow‐Darkening, High‐Yielding, Broadly Adapted Dry Bean Pinto ‘Kimberly’ and ‘Shoshone’
Authors: Singh Shree P. , Terán Henry , Lema Margarita , Dennis Marie F. , Hayes Richard , Robinson Craig
Published: August 2008

Pinto dry bean (Phaseolus vulgaris L.) ‘Kimberly’ (Reg. No. CV‐283, PI 653256) and ‘Shoshone’ (Reg. No. CV‐284, PI 653257) were developed at the University of Idaho‐Kimberly Agricultural Research and Extension Center. Both were released by the Idaho Agricultural Experiment Station on 12 Apr. 2007. Kimberly is a full‐season (100 d to maturity) and Shoshone is an early‐ to medium‐maturing cultivar. Both have light‐colored and slow‐darkening pinto seed. Both are high‐yielding, widely adapted cultivars and possess the bc‐3 and I genes imparting resistance to all strains of Bean common mosaic virus and Bean common mosaic necrosis virus (an aphid‐vectored potyvirus) and to rust [caused by Uromyces appendiculatus (Pers.) Ung.]. Both also have moderate to high levels of resistance to heat and drought. However, both are susceptible to soil zinc deficiency and manganese toxicity.
Registration of Six Tropical Maize Germplasm Lines with Resistance to Aflatoxin Contamination
Authors: Menkir Abebe , Brown Robert L. , Bandyopadhyay Ranajit , Cleveland Thomas E.
Published: August 2008

Six tropical maize (Zea mays L.) germplasm lines, TZAR101 (Reg. No. GP‐568, PI 654048), TZAR102 (Reg. No. GP‐569, PI 654049), TZAR103 (Reg. No. GP‐570, PI 654050), TZAR104 (Reg. No. GP‐571, PI 654051), TZAR105 (Reg. No. GP‐572, PI 654052), and TZAR106 (Reg. No. GP‐573, PI 654053), with resistance to aflatoxin contamination were developed by the International Institute of Tropical Agriculture through a collaborative breeding project with Southern Regional Research Center of the USDA‐ARS. The lines were derived from biparental crosses and backcross populations involving aflatoxin‐resistant tropical elite and temperate inbred lines as parents. These lines had aflatoxin levels similar to or lower than a resistant U.S. inbred check, MI82, in both preliminary and confirmation tests conducted in the laboratory using a kernel‐based screening assay. Further field tests of the six lines under artificial inoculation with an African strain of Aspergillus flavus in Nigeria revealed that these lines had lower levels of aflatoxin compared with elite tropical commercial inbred lines used as checks. These lines also had good agronomic traits and resistance to important diseases in the lowlands, including southern corn leaf blight [caused by Bipolaris maydis (Nisikado & Miyake) Shoemaker], southern corn rust (caused by Puccinia polysora Underw.), and ear rot.
Registration of ‘Monico’ Oat
Authors: Erickson Charles A. , Obert Don E. , Burrup Dave E. , Blake Tom K. , Dillon Merlin A. , Wesenberg Darrell M. , Whitmore James C.
Published: August 2008

‘Monico’ spring oat (Avena sativa L.) (Reg. No. CV‐376, PI 652941) was developed cooperatively by the USDA‐ARS and the Idaho Agricultural Experiment Station (AES) and jointly released by the USDA‐ARS, the Idaho AES, the Montana AES, and the Colorado AES in 2007. Monico was developed using a modified bulk selection program. It is a F4 spaced‐plant selection from the cross 83Ab3119/‘Monida’ harvested in 1993 at Aberdeen, ID. The parent 83Ab3119 had the pedigree of ‘Cayuse’/76Ab6843 (‘Appaloosa’/3/‘Otana’ //Coker X848‐1‐1‐2/Cayuse). Monico is an early to midseason, relatively tall spring oat with excellent yield potential under both irrigated and rainfed conditions in Montana, Idaho, and Colorado.
Refolding of proteins from inclusion bodies is favored by a diminished hydrophobic effect at elevated pressures
Authors: Crisman Ryan L. , Randolph Theodore W.
Published: August 2008

The application of high hydrostatic pressure is an effective tool to promote dissolution and refolding of protein from aggregates and inclusion bodies while minimizing reaggregation. In this study we explored the mechanism of high‐pressure protein refolding by quantitatively assessing the magnitude of the protein–protein interactions both at atmospheric and elevated pressures for T4 lysozyme, in solutions containing various amounts of guanidinium hydrochloride. At atmospheric pressure, the protein– protein interactions are most attractive at moderate guanidinium hydrochloride concentrations (∼1–2 molar), as indicated by a minimum in B22 values. In contrast, at a pressure of 1,000 bar no minimum in B22 values is observed, indicating that high pressures colloidally stabilize protein against aggregation. Finally, experimental values of refractive index increments as a function of pressure indicate that at high pressures, wetting of the hydrophobic surfaces is favored, resulting in a reduction of the hydrophobic effect. This reduction in the hydrophobic effect reduces the driving force for aggregation of (partially) unfolded protein. Biotechnol. Bioeng. 2009;102: 483–492. © 2008 Wiley Periodicals, Inc.
ERM proteins regulate growth cone responses to Sema3A
Authors: Mintz C. David , Carcea Ioana , McNickle Daniel G. , Dickson Tracey C. , Ge Yongchao , Salton Stephen R.J. , Benson Deanna L.
Published: August 2008

Axonal growth cones initiate and sustain directed growth in response to cues in their environment. A variety of events such as receptor internalization, kinase activation, and actin rearrangement can be stimulated by guidance cues and are essential for mediating targeted growth cone behavior. Surprisingly little is known about how such disparate actions are coordinated. Our data suggest that ezrin, radixin, and moesin (ERMs), a family of highly homologous, multifunctional proteins may be able to coordinate growth cone responses to the guidance cue Semaphorin 3A (Sema3A). We show that active ERMs concentrate asymmetrically in neocortical growth cones, are rapidly and transiently inactivated by Sema3A, and are required for Sema3A‐mediated growth cone collapse and guidance. The FERM domain of active ERMs regulates internalization of the Sema3A receptor, Npn1, and its coreceptor, L1CAM, while the ERM C‐terminal domain binds and caps F‐actin. Our data support a model in which ERMs can coordinate membrane and actin dynamics in response to Sema3A. J. Comp. Neurol. 510:351–366, 2008. © 2008 Wiley‐Liss, Inc.
Liraglutide: a new option in the management of type 2 diabetes
Authors: Piya Milan K , Tahrani Abd A , Barnett Anthony H
Published: August 2008

Type 2 diabetes mellitus (T2DM) is a global epidemic with an expected prevalence of 380 million in 2025 worldwide1 and over 2.5 million by 2010 in the UK.2 Diabetes is a progres‐sive disease which leads to macro and microvascular complications and reduced life expectancy.2 Furthermore, diabetes‐related complications have been shown to worsen patients' quality of life.3,4 Copyright © 2008 John Wiley & Sons, Ltd.
Methylnaltrexone for opioid induced constipation
Authors: Chaplin Steve
Published: August 2008

Endogenous opioid peptides are believed to mediate gastrointestinal motor activity and the transport of fluid and electrolytes via μ, kappa and sigma opioid receptors.1 Opioid analgesics have multiple actions on intestinal function, including suppression of neuronal excitability, inhibition of excitatory and inhibitory neuronal inputs to gastrointestinal muscle and mucosa, reduced propulsive peristalsis and increased circular contractions, increased fluid absorption and depression of secretory activity. The net effect is to prolong the oral‐caecal transit time. Copyright © 2008 John Wiley & Sons, Ltd.
Alitretinoin in the treatment of hand eczema
Authors: English John
Published: August 2008

Hand eczema is an umbrella term for dermatoses of different clinical sub‐types involving the hands. It varies in severity from mild changes affecting a few fingers to a severe blistering, itchy eruption involving the entire hand.1 Hand eczema has a major impact on earnings and quality of life, often resulting in repeated con‐sultations, unemployment, time off work and interference with leisure activities.2,3 Copyright © 2008 John Wiley & Sons, Ltd.
Trastuzumab: preparation and planning will avoid chaos
Authors: Chaplin Steve
Published: August 2008

Trastuzumab has been shown to improve disease‐free, and overall, survival in women with early HER2‐positive breast cancer. It is undergoing rapid appraisal by NICE with the aim of providing prompt guidance for use within the NHS. The DOH has pledged to support its use, yet without increasing PCT funding for support services and additional drug costs. The criteria by which PCTs can decide or decline to pay for treatment remain unclear. Copyright © 2006 John Wiley & Sons, Ltd.
Improving CVD risk assessment with eGFR
Authors: Lyon Sue
Published: August 2008

A quiet revolution is taking place within the NHS as laboratories grad‐ually switch from serum creatinine to estimated glomerular filtration rate (eGFR) as the prime measure of renal function. This change follows recommendations in the National Service Framework for Renal Services,1 but the move will have an impact far beyond the renal com‐munity, affecting health profess‐ionals and patients throughout primary and secondary care. Copyright © 2006 John Wiley & Sons, Ltd.
Tigecycline: a novel broad spectrum antibiotic
Authors: Nathwani Dilip
Published: August 2008

Healthcare associated infections (HAIs) affect around 2 million people admitted to acute care hospitals in the USA.1 Approximately 9 per cent of patients in UK hospitals suffer from an infection acquired during their hospital stay,2 many of which are due to multi‐resistant, Gram‐positive and Gram‐negative patho‐gens. The incidence of colonisation and infection with these pathogens continues to rise due to failures in hospital hygiene, selective pressures created by overuse of antibiotics, and mobile elements that can enc‐ode bacterial resistance mechanisms. Copyright © 2006 John Wiley & Sons, Ltd.
Treatment options in pulmonary arterial hypertension
Authors: Toshner Mark
Published: August 2008

Pulmonary arterial hypertension (PAH) is a rare, severe and progressive disease characterised by raised pressures in the arteries in the lungs leading to right heart failure and, historically, a median life expectancy of 2.8 years with‐out targeted treatment.1 Pathologically, it is characterised by a thickening of the muscular layer of the arteries, dysfunction of the vessel walls, and abnormal growth of supporting cells such as fibroblasts. Copyright © 2007 Wiley Interface Ltd
HIV management: emerging therapies in an evolving field
Authors: Gompels Mark , Chisholm Alison
Published: August 2008

Efforts to combat the Human Immunodeficiency Virus (HIV) began in earnest in the late 1980s following the identification and isolation of HIV as the pathogen of the Acquired Immunodeficiency Syndrome (AIDS). Multiple‐drug therapy, known as highly active antiretroviral therapy (HAART), became available in the 1990s and has become the backbone of HIV medication treatment. Understanding of how to optimise its use and effectiveness continues to grow, and is reflected by the emergence of novel agents and new classes of drugs. Copyright © 2007 Wiley Interface Ltd
Advances in the management of inflammatory bowel disease
Authors: Jupp James , Parry Sally
Published: August 2008

Inflammatory bowel disease is a common and complicated disorder that has a great impact on the lives of those affected. This review discusses the properties and uses of the treatments available and possible future advances in therapy. Copyright © 2007 Wiley Interface Ltd
Gliptins: DPP‐4 inhibitors to treat type 2 diabetes
Authors: Green Brian , Flatt Peter , Bailey Clifford
Published: August 2008

Gliptins represent an emerging new class of oral agents to treat type 2 diabetes. They act by inhibiting the enzyme dipeptidyl peptidase‐4 (DPP‐4). This enzyme inactivates the incretin hormones glucagon‐like peptide‐1 (GLP‐1) and glucose‐dependent insulinotropic polypeptide (GIP). These hormones are released from the intestine during a meal and act on the pancreas to increase nutrient‐stimulated insulin secretion. Thus DPP‐4 inhibitors serve as incretin enhancers; they delay inactivation of GLP‐1 and GIP, increasing the insulin response to a meal, which improves glycaemic control. This therapeutic approach carries a low risk of interprandial hypoglycaemia and does not cause weight gain. The first gliptin, sitagliptin (Januvia), was introduced in the UK in April 2007 as ‘add‐on’ therapy for patients with type 2 diabetes inadequately controlled with metformin or a thiazolidinedione. Other gliptins, notably vildagliptin (Galvus), saxagliptin and alogliptin are advanced in clinical development. Copyright © 2007 John Wiley & Sons, Ltd.
IL‐6 inhibition in the treatment of rheumatoid arthritis
Authors: Taylor Peter
Published: August 2008

The armentarium of potential therapeutics for rheumatoid arthritis (RA) has grown with the identification of relevant disease molecules. Of these, biologic therapeutics targeting tumour necrosis factor‐alpha (TNF‐alpha), particularly when used in combination with oral methotrexate, have enjoyed notable success in suppressing inflammation and markedly inhibiting the progression of structural damage previously thought to be an unavoidable characteristic of RA.1,2 However, despite the unprecedented clinical and commercial successes of TNF inhibitors, their availability is restricted by high costs and the failure of a substantial proportion of patients to demonstrate significant clinical responses. Copyright © 2007 John Wiley & Sons, Ltd.
Fentanyl buccal tablet for cancer breakthrough pain
Authors: Zeppetella Giovambattista
Published: August 2008

Pain is one of the most common symptoms of advanced cancer and has significant adverse effects on patients' functioning and quality of life.1 A number of studies have established that pain can be controlled in the majority of patients using the World Health Organization (WHO) guidelines,2 however, even when background pain is well controlled, 70–90 per cent of patients with advanced cancer also experience brief episodes or flares of severe pain, known as breakthrough pain.3 Copyright © 2008 John Wiley & Sons, Ltd.
Rivaroxaban: a new orally active direct inhibitor of Factor Xa
Authors: Chaplin Steve
Published: August 2008

Deep vein thrombosis (DVT) is a common complication in hospital patients who do not receive thromboprophylaxis. Due to the shortcomings of the available evidence the true incidence is unclear, but data from the placebo arms of randomised trials of thromboprophylaxis, believed to be the best source,1 show that the incidence varies by specialty (Table 1). The risk in medical inpatients is often underestimated: the incidence of DVT is particularly high among patients admitted with stroke, heart failure or myocardial infarction.2 However, patients undergoing orthopaedic surgery are at greatest risk, with DVT occurring in approximately one‐quarter to one‐half. There is also evidence to suggest that individual risk is influenced by a large number of risk factors (Table 2).1 Copyright © 2008 John Wiley & Sons, Ltd.
The endocannabinoid system: a therapeutic target in patients with abdominal obesity?
Authors: Haslam David
Published: August 2008

The endocannabinoid system (ECS) is a relatively recently discovered endogenous system involved in energy balance and homeostasis. The discovery of the receptors and endogenous agonists for this system in the late 1980s and 1990s prompted intense research into the modulation of this system for therapeutic benefit. This research bore fruition with the characterisation; clinical development programme; and, in 2006, licensing, of the first cannabinoid receptor 1 (CB1) blocker, rimonabant (Accomplia; sanofiaventis). Rimonabant was licensed in 12 European countries, as well as Argentina, Mexico, Columbia, Chile, the United Arab Emirates and Hong Kong, and is licensed in Europe as an adjunct to diet and exercise for the treatment of obese patients (body mass index [BMI] ≥30kg per m2) or overweight patients (BMI >27kg per m2) with associated risk factors, such as type 2 diabetes or dyslipidaemia. Copyright © 2008 John Wiley & Sons, Ltd.
Commonality in the LME aluminum and copper volatility processes through a FIGARCH lens
Authors: Figuerola‐Ferretti Isabel , Gilbert Christopher L.
Published: August 2008

Dynamic representation of spot and three‐month aluminum and copper volatilities is considered. Aluminum and copper are the two most important metals traded in the London Metal Exchange. They share common business cycle factors and are traded under identical contract specifications. The bivariate FIGARCH model, which allows parsimonious representation of long memory volatility processes, is applied. The results show that spot and three‐month aluminum and copper volatilities follow long memory processes, that they exhibit a common degree of fractional integration and that the processes are symmetric. However, there is no evidence that the processes are fractionally cointegrated. This high degree of commonality may result from the common LME trading process. © 2008 Wiley Periodicals, Inc. Jrl Fut Mark 28:935–962, 2008
An examination of the complementary volume–volatility information theories
Authors: Chen Zhiyao , Daigler Robert T.
Published: August 2008

The volume–volatility relationship during the dissemination stages of information flow is examined by analyzing various theories relating volume and volatility as complementary rather than competing models. The mixture of distributions hypothesis, sequential arrival of information hypothesis, the dispersion of beliefs hypothesis, and the noise trader hypothesis all add to the understanding of how volume and volatility interact for different types of futures traders. An integrated picture of the volume–volatility relationship is provided by investigating the dynamic linear and nonlinear associations between volatility and the volume of informed (institutional) and uninformed (the general public) traders. In particular, the trading behavior explanation for the persistence of futures volatility, the effect of the timing of private information arrival, and the response of institutional traders to excess noise trading risk is examined. © 2008 Wiley Periodicals, Inc. Jrl Fut Mark 28:963–992, 2008
Realized volatility and correlation in energy futures markets
Authors: Wang Tao , Wu Jingtao , Yang Jian
Published: August 2008

Using high‐frequency returns, realized volatility and correlation of the NYMEX light, sweet crude oil, and Henry‐Hub natural gas futures contracts are examined. The unconditional distributions of daily returns and daily realized variances are non‐Gaussian, whereas the distributions of the standardized returns (normalized by the realized standard deviation) and the (logarithms of) realized standard deviations appear approximately Gaussian. The (logarithms of) standard deviations exhibit long‐memory, but the realized correlation between the two futures does not, implying rather weak inter‐market linkage in the long run. There is evidence of asymmetric volatility for natural gas but not for crude oil futures. Finally, realized crude oil futures volatility responds with an increase in the weeks immediately before the OPEC events recommending price increases. © 2008 Wiley Periodicals, Inc. Jrl Fut Mark 28:993–1011, 2008
Pregnancy and sexual health among homeless young injection drug users
Authors: Hathazi Dodi , Lankenau Stephen E. , Sanders Bill , Jackson Bloom Jennifer
Published: August 2008

Research on pregnancy and sexual health among homeless youth is limited. In this study, qualitative interviews were conducted with 41 homeless young injection drug users (IDUs) in Los Angeles with a history of pregnancy. The relationship between recent pregnancy outcomes, contraception practices, housing status, substance use, utilization of prenatal care, and histories of sexual victimization are described. A total of 81 lifetime pregnancies and 26 children were reported. Infrequent and ineffective use of contraception was common. While pregnancy motivated some homeless youth to establish housing, miscarriages and terminations were more frequent among youth who reported being housed. Widespread access to prenatal and medical services was reported during pregnancy, but utilization varied. Many women continued to use substances throughout pregnancy. Several youth reported childhood sexual abuse and sexual victimization while homeless. Pregnancy presents a unique opportunity to encourage positive health behaviors in a high‐risk population seldom seen in a clinical setting.
Community structural instability, anomie, imitation and adolescent suicidal behavior
Authors: Thorlindsson Thorolfur , Bernburg Jón Gunnar
Published: August 2008

The current study examines the contextual effects of community structural characteristics, as well as the mediating role of key social mechanisms, on youth suicidal behavior in Iceland. We argue that the contextual influence of community structural instability on youth suicidal behavior should be mediated by weak attachment to social norms and values (anomie), and contact with suicidal others (suggestion‐imitation). The data comes from a national survey of 14–16 years old adolescents. Valid questionnaires were obtained from 7018 students (response rate about 87%). The findings show that the community level of residential mobility has a positive, contextual effect on adolescent suicidal behavior. The findings also indicate that the contextual effect of residential mobility is mediated by both anomie and suggestion‐imitation. The findings offer the possibility to identify communities that carry a substantial risk for adolescent suicide as well as the mechanisms that mediate the influence of community structural characteristics on adolescent risk behavior.
Screen media time usage of 12–16 year‐old Spanish school adolescents: Effects of personal and socioeconomic factors, season and type of day
Authors: Devís‐Devís José , Peiró‐Velert Carmen , Beltrán‐Carrillo Vicente J. , Tomás José Manuel
Published: August 2008

This study examined screen media time usage (SMTU) and its association with personal and socioeconomic factors, as well as the effect of season and type of day, in a Spanish sample of 12–16 year‐old school adolescents (N= 323). The research design was a cross‐sectional survey, in which an interviewer‐administered recall questionnaire was used. Statistical analyses included repeated measures analyses of variance, analysis of covariance and structural equation models. Results showed an average of 2.52 h per day of total SMTU and partial times of 1.73 h per day in TV viewing, 0.27 h per day in computer/videogames, and 0.52 h per day in mobile use. Four significant predictors of SMTU emerged. Firstly, the type of school was associated with the three media of our study, particularly students from state/public school spent more time on them than their private schools counterparts. Secondly, older adolescents (14–16 years old) were more likely to use computer/videogame and mobile phone than younger adolescents. Thirdly, the more accessibility to household technology the more probable computer/videogames and mobile phone were used. Finally, boys spent significantly more time in mobile phone than girls. Additionally, results revealed that adolescents seemed to consume more TV and computer/videogames in autumn than in winter, and more TV and mobile phones on weekends than on weekdays, especially among state school students. Findings from this study contribute to the existing knowledge on adolescents' SMTU patterns that can be transferred to families and policies.
Social bonds and Internet pornographic exposure among adolescents
Authors: Mesch Gustavo S.
Published: August 2008

Concern has grown regarding possible harm to the social and psychological development of children and adolescents exposed to Internet pornography. Parents, academics and researchers have documented pornography from the supply side, assuming that its availability explains consumption satisfactorily. The current paper explored the user's dimension, probing whether pornography consumers differed from other Internet users, as well as the social characteristics of adolescent frequent pornography consumers. Data from a 2004 survey of a national representative sample of the adolescent population in Israel were used (n= 998). Adolescent frequent users of the Internet for pornography were found to differ in many social characteristics from the group that used the Internet for information, social communication and entertainment. Weak ties to mainstream social institutions were characteristic of the former group but not of the latter. X‐rated material consumers proved to be a distinct sub‐group at risk of deviant behaviour.
Gender‐specific differences in left ventricular remodelling and fibrosis in hypertrophic cardiomyopathy: Insights from cardiovascular magnetic resonance
Authors: Schulz‐Menger Jeanette , Abdel‐Aty Hassan , Rudolph Andre , Elgeti Thomas , Messroghli Daniel , Utz Wolfgang , Boyé Philipp , Bohl Steffen , Busjahn Andreas , Hamm Bernd , Dietz Rainer
Published: August 2008

Background:

Gender is an independent risk factor for heart failure mortality in hypertrophic cardiomyopathy (HCM).

Aims:

To explore the interaction between gender, myocardial fibrosis and remodelling in HCM.

Methods:

We studied 64 HCM patients (28 females, aged 51 ± 16 years) categorized as non‐obstructive (HNCM, n=31) or obstructive (HOCM, n=33) and 60 healthy subjects (31 females, aged 43 ± 14 years). Cine imaging was performed to assess left ventricular volumes and mass. LV remodelling index (LVRI) was calculated. Extension of late gadolinium enhancement (LGE) was quantified.

Results:

Females in the control group and in the HNCM group had a lower LVRI than males (control: 0.7±0.1 vs. 0.9±0.2 g/ml, <0.002; HNCM: 1.1±0.2 vs. 1.5±0.5 g/ml, p<0.001). In contrast, HOCM females had a similar LVRI compared to males (1.8±0.5 vs. 1.7±0.4 g/ml, p=ns). Thus the increase in LVRI was more pronounced in females compared to males. LGE was noted in 70% of the patients. No relation was found between the presence or the quantity of myocardial fibrosis and gender in any of the patient subgroups.

Conclusion:

Our data suggest a disproportionate degree of remodelling in different forms of HCM depending on gender. Gender does not appear to influence the quantity of fibrosis as defined by LGE.
Non‐sustained ventricular tachycardia as a predictor of sudden cardiac death in patients with left ventricular dysfunction: A meta‐analysis
Authors: de Sousa Marcos R. , Morillo Carlos A. , Rabelo Fábio T. , Filho Antônio M. Nogueira , Ribeiro Antonio L.P.
Published: August 2008

Background:

Identifying patients at risk of sudden cardiac death (SCD) remains a challenge.

Aim:

To evaluate the performance of non‐sustained ventricular tachycardia (NSVT) from 24 hour ambulatory electrocardiography as a predictor of SCD in patients with heart failure or non‐ischaemic dilated cardiomyopathy with left ventricular systolic dysfunction (LVSD).

Methods and results:

Study search and selection were performed by independent reviewers using a validated strategy. Eleven prognostic studies with > 100 patients with good quality data and multivariate analysis of predictors of SCD were included. Publication bias was evaluated by funnel plot with Kendall's tau b test. A summary ROC (sROC) curve was built to evaluate predictive performance of NSVT. There was threshold effect (Spearman's correlation between sensitivity and specificity=−0.818, p<0.01) which indicates that combining sensitivity and specificity was not appropriate. The area of 0.68±0.02 under the sROC curve indicates a statistically significant contribution of NSVT in the prediction of SCD. The true negative rate varied from 89 to 97%. Multivariate analysis and meta‐regression suggested that the contribution of NSVT to risk stratification is independent of ejection fraction.

Conclusions:

Absence of NSVT indicated a low probability of SCD in patients with LVSD. A risk score including NSVT should be evaluated in prospective studies.
The crystal structure of seabream antiquitin reveals the structural basis of its substrate specificity
Authors: Tang Wai-Kwan , Wong Kam-Bo , Lam Yuk-Man , Cha Sun-Shin , Cheng Christopher H.K. , Fong Wing-Ping
Published: August 2008

The crystal structure of seabream antiquitin in complex with the cofactor NAD+ was solved at 2.8 Å resolution. The mouth of the substrate‐binding pocket is guarded by two conserved residues, Glu120 and Arg300. To test the role of these two residues, we have prepared the two mutants E120A and R300A. Our model and kinetics data suggest that antiquitin's specificity towards the substrate α‐aminoadipic semialdehyde is contributed mainly by Glu120 which interacts with the α‐amino group of the substrate. On the other hand, Arg300 does not have any specific interaction with the α‐carboxylate group of the substrate, but is important in maintaining the active site conformation.
Fhit proteins can also recognize substrates other than dinucleoside polyphosphates
Authors: Guranowski Andrzej , Wojdyła Anna M. , Pietrowska-Borek Małgorzata , Bieganowski Paweł , Khurs Elena N. , Cliff Matthew J. , Blackburn G. Michael , Błaziak Damian , Stec Wojciech J.
Published: August 2008

We show here that Fhit proteins, in addition to their function as dinucleoside triphosphate hydrolases, act similarly to adenylylsulfatases and nucleoside phosphoramidases, liberating nucleoside 5′‐monophosphates from such natural metabolites as adenosine 5′‐phosphosulfate and adenosine 5′‐phosphoramidate. Moreover, Fhits recognize synthetic nucleotides, such as adenosine 5′‐O‐phosphorofluoridate and adenosine 5′‐O‐(γ‐fluorotriphosphate), and release AMP from them. With respect to the former, Fhits behave like a phosphodiesterase I concomitant with cleavage of the P–F bond. Some kinetic parameters and implications of the novel reactions catalyzed by the human and plant (Arabidopsis thaliana) Fhit proteins are presented.
Management of acute renal failure in cats using peritoneal dialysis: A retrospective study of six cases (2003–2007)
Authors: Dorval Patricia , Boysen Søren R.
Published: August 2008

Information regarding the use and success of peritoneal dialysis (PD) in the management of acute renal failure (ARF) in cats is lacking. The purpose of this retrospective study is to describe the indications, efficacy, complications and outcome of cats undergoing PD for ARF. Six cats that underwent PD for treatment of ARF of various etiologies were included. PD effectively replaced renal function in all cats and allowed renal recovery in 5/6 cats. Five cats were discharged and one cat died. Complications were reported in all cats and included subcutaneous edema ( n=5), hyperglycemia ( n=4), dialysate retention ( n=3), and hypoalbuminemia ( n=3). A novel technique consisting of a Blake surgical drain and an intermittent closed suction system was used, which appears to be a viable option for PD in cats. Although complications are common, PD is an effective renal replacement therapy for ARF in cats and carries a reasonable prognosis in selected cases.
A chronology of the Little Ice Age in the tropical Andes of Bolivia (16°S) and its implications for climate reconstruction
Authors: Rabatel Antoine , Francou Bernard , Jomelli Vincent , Naveau Philippe , Grancher Delphine
Published: August 2008

Dating moraines by lichenometry enabled us to reconstruct glacier recession in the Bolivian Andes since the Little Ice Age maximum. On the 15 proglacial margins studied, we identified a system of ten principal moraines that marks the successive positions of glaciers over the last four centuries. Moraines were dated by performing statistical analysis of lichen measurements based on the extreme values theory. Like glaciers in many mid-latitude mountain areas, Bolivian glaciers reached their maximal extent during the second half of the 17th century. This glacier maximum coincides with the Maunder minimum of solar irradiance. By reconstructing the equilibrium-line altitude and changes in mass-balance, we think the glacier maximum may be due to a 20 to 30% increase in precipitation and a 1.1 to 1.2 °C decrease in temperature compared with present conditions. In the early 18th century, glaciers started to retreat at varying rates until the late 19th to early 20th century; this trend was generally associated with decreasing accumulation rates. By contrast, glacier recession in the 20th century was mainly the consequence of an increase in temperature and humidity. These results are consistent with observations made in the study region based on other proxies.
Teammerkmale und Teamdiagnose – Arbeits- und Sportteams im Vergleich
Authors: Lau Andreas , Kauffeld Simone , Schliermann Rainer , Conrad Jana , Stoll Oliver
Published: August 2008

Zusammenfassung. Auf der Basis überwiegender Gemeinsamkeiten in der Einschätzung von Gruppenmerkmalen zwischen realen Arbeits- und Sportteams geht der Beitrag zunächst der Frage nach, welche Modelle zur Beschreibung und Analyse von Gruppenaufgaben und -merkmalen in der Kleingruppenforschung favorisiert werden und in wie weit diese in Verbindung mit Instrumenten zur Teamdiagnose in der Arbeits- und Sportpsychologie stehen. Das Kasseler Teampyramide-Modell ( Kauffeld, 2001 ) und der daraus abgeleitete Fragebogen zur Arbeit im Team (F-A-T) von Kauffeld (2004) werden als schlüssig für die Anwendung im Sport bewertet. Der F-A-T wurde daher in einer Feldstudie bei Sportteams (G = 27, N = 255) eingesetzt. Der Versuch, die strukturelle Validität des F-A-T im Sport zu replizieren, gelingt zwar im Wesentlichen, allerdings werden in einigen psychometrischen Parametern (z. B. Cronbachs α) keine zufriedenstellenden Werte erzielt. Es wird empfohlen, ein sportspezifisches Teamdiagnoseinstrument zu entwickeln.
Trainerinnen und Trainer im Frauenfußball aus Sicht der Athletinnen
Authors: Pfeffer Ines , Gallitschke Mandy
Published: August 2008

Zusammenfassung. In der Mannschaftssportart Frauenfußball wird der Einfluss der aus Athletensicht wahrgenommenen Trainer-Athlet-Interaktion auf die Zufriedenheit der Sportlerinnen in Abhängigkeit vom Geschlecht des Trainers untersucht. In einer querschnittlichen Fragebogenstudie wurden neben der subjektiven Beurteilung des Führungsverhaltens (Leadership Scale for Sports; LSS) und des motivationalen Trainingsklimas (Perceived Motivational Climate in Sports Questionnaire; PMCSQ) Daten zur Zufriedenheit von 150 Sportlerinnen (10 Mannschaften) von fünf weiblichen und fünf männlichen Trainern der 2. und 3. Liga erfasst. Die Ergebnisse zeigen, dass die Trainer-Athlet-Interaktion im Zusammenhang mit dem Geschlecht des Trainers und dem Wettkampfniveau der Athletinnen betrachtet werden muss. Trainerinnen werden entgegen den Erwartungen weniger sozial unterstützend, weniger belohnend und weniger demokratisch eingeschätzt als ihre männlichen Kollegen. Spielerinnen der 2. Liga nehmen das Trainingsklima erwartungsgemäß stärker wettbewerbsorientiert wahr als Athletinnen der 3. Liga. Die Zufriedenheit der Athletinnen geht insgesamt mit einem ausgeprägt aufgabenorientierten und wenig wettbewerbsorientierten Trainingsklima einher. Allerdings sind verschiedene Faktoren der Trainer-Athlet-Interaktion für die Zufriedenheit der Spielerinnen verantwortlich, differenziert man nach dem Geschlecht des Trainers.
Research Note
Authors: Strauß Bernd , Bierschwale Jens
Published: August 2008

Zusammenfassung. Häufig wird angenommen, Zuschauer würden einen Beitrag zu einem Heimvorteil in den Mannschaftssportarten leisten. Die bisherigen Untersuchungen, insbesondere zum Fußball und den klassischen amerikanischen Mannschaftssportarten wie Eishockey und Basketball zeigen in der Regel allerdings nur kleine oder gar keine Zusammenhänge zwischen den Zuschauer- und Leistungsvariablen. Bislang gab es keine Untersuchung, die sich mit dem Heimvorteil im Hallenhandball beschäftigt hat. In dieser Studie wurden N = 5003 Spiele der 1. Handballbundesliga von 1977 bis 2000 hinsichtlich Ergebnissen und Zuschauerkennziffern analysiert. Es zeigte sich ein deutlicher Heimvorteil in der Handballbundesliga. Über den gesamten Zeitraum ergeben sich 66.26 % Heimsiege (bei 11.45 % Unentschieden und 22.29 % Auswärtserfolgen). Es existieren allenfalls nur sehr kleine Korrelationen oder Nullkorrelationen zwischen den Zuschauermaßen wie der Zuschaueranzahl und der Zuschauerdichte und den Leistungsmaßen (wie Punkte und Tordifferenz), die aber weniger als maximal 1 % der Varianz aufklären und damit überhaupt keine praktische Bedeutsamkeit besitzen (z. B. bei Kontrolle der Leistungsstärke der beiden Teams zwischen Heimpunkten und a) der Zuschaueranzahl rp = .05; p < .01; N = 4645), b) der Zuschauerdichte (rp = 0; N = 4645) und c) dem Zuschauerquotienten (rp = −.04, p < .01; N = 4645)). Die Ergebnisse dieser Studie bestätigen zahlreiche vorherige empirische Studien (vgl. Carron et al., 2005 ; Jones et al., 2007 ; Strauß, 1999 ; 2002a ), die einen substantiellen Zusammenhang von Zuschauern und dem Heimvorteil eher verneinen.