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Crash
Kinds of Crash Terms modified by Crash Selected AbstractsThe Political Consequences of the CrashPOLITICAL STUDIES REVIEW, Issue 1 2010Andrew Gamble The financial crash of 2008 precipitated a major recession. It shattered the financial growth model that had dominated the previous twenty years and plunged the international economy into a period of economic and political restructuring of uncertain duration. The immediate origins of the crash lay in the lending practices associated with the sub-prime mortgages in the United States which produced the credit crunch in 2007, but the wider causes were the unbalanced character of growth in the international economy and the particular role played by finance. The crisis has been explained in a number of different ways, focusing on the behaviour of the financial markets, the institutional and policy conditions that made the boom possible and then undermined it, longer-term economic and policy cycles and the nature of uncertainty and risk in complex social systems. The political impact of the crash and the recession has not been uniform; it has been highly uneven, depending on the position of particular states in the international economy. The rapid interventions by governments to stave off financial collapse at the end of 2008 were successful, but at the cost of creating serious problems of adjustment for the future. The political debate around what were the causes, who should be blamed and what should be done is only just beginning, and the way this crisis comes to be understood will play a major part in determining how it is eventually resolved and how far-reaching will be the changes to the international economy and to domestic politics. [source] The analysis of motor vehicle crash clusters using the vector quantization techniqueJOURNAL OF ADVANCED TRANSPORTATION, Issue 3 2010Lorenzo Mussone Abstract In this paper, a powerful tool for analyzing motor vehicle data based on the vector quantization (VQ) technique is demonstrated. The technique uses an approximation of a probability density function for a stochastic vector without assuming an "a priori" distribution. A self-organizing map (SOM) is used to transform accident data from an N-dimensional space into a two-dimensional plane. The SOM retains all the original data yet provides an effective visual tool for describing patterns such as the frequency at which a particular category of events occurs. This enables new relationships to be identified. Accident data from three cities in Italy (Turin, Milan, and Legnano) are used to illustrate the usefulness of the technique. Crashes are aggregated and clustered crashes by type, severity, and along other dimensions. The paper includes discussion as to how this method can be utilized to further improve safety analysis. Copyright © 2010 John Wiley & Sons, Ltd. [source] The Impact of Underage Drinking Laws on Alcohol-Related Fatal Crashes of Young DriversALCOHOLISM, Issue 7 2009James C. Fell Background:, This study used a pre- to post-design to evaluate the influence on drinking-and-driving fatal crashes of 6 laws directed at youth aged 20 and younger and 4 laws targeting all drivers. Methods:, Data on the laws were drawn from the Alcohol Policy Information System data set (1998 to 2005), the Digests of State Alcohol Highway Safety Related Legislation (1983 to 2006), and the Westlaw database. The Fatality Analysis Reporting System data set (1982 to 2004) was used to assess the ratio of drinking to nondrinking drivers involved in fatal crashes [fatal crash incidence ratio (CIR)]. The data were analyzed using structural equation modeling techniques. Results:, Significant decreases in the underage fatal CIR were associated with presence of 4 of the laws targeting youth (possession, purchase, use and lose, and zero tolerance) and 3 of the laws targeting all drivers (0.08 blood alcohol concentration illegal per se law, secondary or upgrade to a primary seat belt law, and an administrative license revocation law). Beer consumption was associated with a significant increase in the underage fatal CIR. The direct effects of laws targeting drivers of all ages on adult drinking drivers aged 26 and older were similar but of a smaller magnitude compared to the findings for those aged 20 and younger. It is estimated that the 2 core underage drinking laws (purchase and possession) and the zero tolerance law are currently saving an estimated 732 lives per year controlling for other exposure factors. If all states adopted use and lose laws, an additional 165 lives could be saved annually. Conclusions:, These results provide substantial support for the effectiveness of under age 21 drinking laws with 4 of the 6 laws examined having significant associations with reductions in underage drinking-and-driving fatal crashes. These findings point to the importance of key underage drinking and traffic safety laws in efforts to reduce underage drinking-driver crashes. [source] The Dog That Did Not Bark: Insider Trading and CrashesTHE JOURNAL OF FINANCE, Issue 5 2008JOSE M. MARIN ABSTRACT This paper documents that at the individual stock level, insiders' sales peak many months before a large drop in the stock price, while insiders' purchases peak only the month before a large jump. We provide a theoretical explanation for this phenomenon based on trading constraints and asymmetric information. A key feature of our theory is that rational uninformed investors may react more strongly to the absence of insider sales than to their presence (the "dog that did not bark" effect). We test our hypothesis against competing stories, such as insiders timing their trades to evade prosecution. [source] Characteristics of Crashes With Farm Equipment That Increase Potential for InjuryTHE JOURNAL OF RURAL HEALTH, Issue 4 2007Corinne Peek-Asa MPH ABSTRACT:,Context:Crash fatality and injury rates are higher on rural roadways than other roadway types. Although slow-moving farm vehicles and equipment are risk factors on rural roads, little is known about the characteristics of crashes with farm vehicles/equipment.Purpose:To describe crashes and injuries for the drivers of farm vehicles/equipment and non-farm vehicles involved in an injury crash. Passengers are not included in this analysis.Methods:Injury crashes were included that involved a farm vehicle/equipment and at least one non-farm vehicle reported in Iowa Department of Transportation crash data from 1995 to 2004. Odds ratios were calculated through logistic regression to identify increased odds for injury among drivers of non-farm vehicles and farm vehicles/equipment. We examined frequently occurring crash characteristics to identify crash scenarios leading to the highest odds for injury.Findings:Non-farm vehicle drivers were 5.23 times more likely to be injured than farm vehicle/equipment drivers (95% CI = 4.12,6.46). The absence of restraint use was a significant predictor of injury for both farm vehicle/equipment drivers (OR = 2.85; 95% CI = 1.14,7.13) and non-farm vehicle drivers (OR = 2.53; 95% CI = 1.54,4.15). Crash characteristics increasing the odds of injury for non-farm vehicle drivers included speeding, passing the farm vehicle/equipment, driving on a county road, having a frontal impact collision, and crashing in darkness. Ejection was the strongest predictor of injury for the farm vehicle/equipment driver.Conclusion:Non-farm vehicle drivers were much more likely to be injured than farm vehicle/equipment drivers, suggesting that farm vehicle/equipment crash prevention should be a priority for all rural road users. Prevention strategies that reduce motor vehicle speed, assist in safe passing, increase seat belt use, and increase conspicuousness of the farm vehicle/equipment are suggested. [source] Fatal Passenger Vehicle Crashes With At Least 1 Driver Younger Than 15 Years: A Fatality Analysis Reporting System StudyTHE JOURNAL OF RURAL HEALTH, Issue 2 2007Larry Frisch MD ABSTRACT:,Context: A small number of fatalities continue to occur due to motor vehicle crashes on highways in which at least 1 passenger vehicle (automobile, van, or small truck) is driven by a child younger than 15 years. Purpose: The purpose of this study was to extend previous work suggesting that such crashes occur frequently in the Southern states and have relatively high rates in rural areas in the South and Great Plains. Methods: This study utilizes data for the 5-year period 1999-2003 from the National Highway Transportation Safety Administration's online Fatality Analysis Reporting System. All cases were identified in which at least 1 conventional passenger vehicle in a fatal crash was being driven by a child younger than 15 years. Findings: During the 5-year period, 350 fatal crashes occurred with at least 1 driver younger than 15 years involved. Twenty-one of these drivers were licensed (11) or driving with a learner's permit (10). A total of 987 individuals in 419 vehicles were involved in these crashes, and 402 deaths resulted (1.16 deaths/crash). These crashes occurred primarily in Texas, Florida, Arkansas, and Arizona, but the highest rates per 100,000 children were found in North and South Dakota and predominantly in a band of Intermountain and Plains states. There was a strong correlation between crash rates and several measures of rurality. Conclusions: Crashes involving young, largely unlicensed, drivers account for about 70 deaths yearly. [source] Clinical and Economic Factors Associated with Ambulance Use to the Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 8 2006Jennifer Prah Ruger PhD Background: Concern about ambulance diversion and emergency department (ED) overcrowding has increased scrutiny of ambulance use. Knowledge is limited, however, about clinical and economic factors associated with ambulance use compared to other arrival methods. Objectives: To compare clinical and economic factors associated with different arrival methods at a large, urban, academic hospital ED. Methods: This was a retrospective, cross-sectional study of all patients seen during 2001 (N= 80,209) at an urban academic hospital ED. Data were obtained from hospital clinical and financial records. Outcomes included acuity and severity level, primary complaint, medical diagnosis, disposition, payment, length of stay, costs, and mode of arrival (bus, car, air-medical transport, walk-in, or ambulance). Multivariate logistic regression identified independent factors associated with ambulance use. Results: In multivariate analysis, factors associated with ambulance use included: triage acuity A (resuscitation) (adjusted odds ratio [OR], 51.3; 95% confidence interval [CI] = 33.1 to 79.6) or B (emergent) (OR, 9.2; 95% CI = 6.1 to 13.7), Diagnosis Related Group severity level 4 (most severe) (OR, 1.4; 95% CI = 1.2 to 1.8), died (OR, 3.8; 95% CI = 1.5 to 9.0), hospital intensive care unit/operating room admission (OR, 1.9; 95% CI = 1.6 to 2.1), motor vehicle crash (OR, 7.1; 95% CI = 6.4 to 7.9), gunshot/stab wound (OR, 2.1; 95% CI = 1.5 to 2.8), fell 0,10 ft (OR, 2.0; 95% CI = 1.8 to 2.3). Medicaid Traditional (OR, 2.0; 95% CI = 1.4 to 2.4), Medicare Traditional (OR, 1.8; 95% CI = 1.7 to 2.1), arrived weekday midnight,8 AM (OR, 2.0; 95% CI = 1.8 to 2.1), and age ,65 years (OR, 1.3; 95% CI = 1.2 to 1.5). Conclusions: Ambulance use was related to severity of injury or illness, age, arrival time, and payer status. Patients arriving by ambulance were more likely to be acutely sick and severely injured and had longer ED length of stay and higher average costs, but they were less likely to have private managed care or to leave the ED against medical advice, compared to patients arriving by independent means. [source] Single Question about Drunkenness to Detect College Students at Risk for InjuryACADEMIC EMERGENCY MEDICINE, Issue 6 2006Mary Claire O'Brien MD Abstract Objectives: To examine the frequency of injuries reported by college students who replied affirmatively to the question, "In a typical week, how many days do you get drunk?" Methods: In Fall 2003, a Web-based survey was administered to a stratified random sample of 3,909 college students from ten North Carolina (NC) universities. Students answered questions regarding alcohol use and its consequences. Data were analyzed using multiple logistic regression, controlling for within-school clustering of drinking behaviors and adjusting for other significant covariates. Adjusted odds ratios (AORs) and 95% confidence intervals (CI) were calculated for significant predictors (p < 0.05). Results: Two thousand four hundred eighty-eight students reported that they are current drinkers; 1,353 (54.4%) reported getting drunk at least once in a typical week. Compared with students who did not report getting drunk at least once a week, these students had higher odds of being hurt or injured at least once as a result of their own drinking (AOR = 4.97; 95% CI = 3.47 to 7.09), experiencing a fall from a height that required medical treatment (AOR = 2.16; 95% CI = 1.36 to 3.43), and being taken advantage of sexually as a result of another's drinking (AOR = 2.59; 95% CI = 1.72 to 3.89). Students who reported getting drunk at least one day in a typical week also were more likely to cause an injury requiring medical treatment to someone else. They had higher odds of causing injury in an automobile crash (AOR = 1.84; 95% CI = 1.01 to 3.40), of causing a burn that required medical treatment (AOR = 2.85; 95% CI = 1.51 to 5.39), and of causing a fall from a height that required medical treatment (AOR = 2.02; 95% CI = 1.01 to 4.04). Getting drunk was a better indicator of "self-experienced injury" and of "injury caused to someone else" than was binge drinking, for all outcomes (p < 0.05). Conclusions: The single question, "In a typical week, how many days do you get drunk?" identifies college students who are at higher than normal risk of injury as a result of their own drinking and the drinking of others. Future research should assess this question's effectiveness as a screening tool in campus health centers and in emergency departments. [source] Health Status among Emergency Department Patients Approximately One Year after Consecutive Disasters in New York CityACADEMIC EMERGENCY MEDICINE, Issue 10 2005William George Fernandez MD Abstract Objectives: Emergency department (ED) patients with disaster-related experiences may present with vague symptoms not clearly linked to the event. In 2001, two disasters in New York City, the World Trade Center disaster (WTCD) and the subsequent American Airlines Flight 587 crash, presented an opportunity to study long-term consequences of cumulative disaster exposure (CDE) on health-related quality of life (HRQOL) among ED patients. Methods: From July 15 to October 30, 2002, a systematic sample of stable, adult patients from two EDs in New York City were enrolled. Participants completed a self-administered questionnaire. The Short Form 36 (SF-36) was used to assess overall health status. Bivariate analyses were conducted to identify individual correlates of worsening health status. Multivariate regression was performed to identify the association between various factors and overall health status, while controlling for relevant sociodemographic variables. Results: Four hundred seventy-one patients (54.6% female) participated. The participation rate was 73.4%. One hundred sixty-one participants (36%) reported direct, indirect, or occupational exposure to the WTCD; 55 (13.3%) had direct, indirect, or occupational exposure to the plane crash; 33 (8.1%) had both exposures. In separate multivariate models, CDE predicted lower SF-36 scores for general health (p < 0.0096), mental health (p < 0.0033), and bodily pain (p < 0.0046). Conclusions: In the year following mass traumatic events, persons with CDE had lower overall health status than those with one or no disaster exposure. Clinicians should consider the impact that traumatic events have on the overall health status of ED patients in the wake of consecutive disasters. [source] The mid-season crash in aphid populations: why and how does it occur?ECOLOGICAL ENTOMOLOGY, Issue 4 2004A. J. Karley Abstract., 1. Aphid populations on agricultural crops in temperature regions collapse over a few days from peak numbers to local extinction soon after mid-summer (e.g. mid-July in the U.K.). The populations recover 6,8 weeks later. There is anecdotal or incidental evidence of an equivalent mid-season population crash of aphids on grasses and forbs in natural vegetation. 2. The ecological factors causing the mid-season population crash of aphids include a decline in plant nutritional quality and increased natural enemy pressure as the season progresses. Extreme weather events, e.g. severe rainstorms, can precipitate the crash but weather conditions are not a consistent contributory factor. 3. The population processes underlying the crash comprise enhanced emigration, especially by alate (winged) aphids, depressed performance resulting in reduced birth rates, and elevated mortality caused by natural enemies. 4. Mathematical models, previously applied to aphid populations on agricultural crops, have great potential for studies of aphid dynamics in natural vegetation. In particular, they can help identify the contribution of various ecological factors to the timing of the population crash and offer explanations for how slow changes in population processes can result in a rapid collapse of aphid populations. [source] Influence of the Unbelted Rear-seat Passenger on Driver Mortality: "The Backseat Bullet"ACADEMIC EMERGENCY MEDICINE, Issue 2 2005James Mayrose PhD Abstract Objectives: This study examined whether unrestrained left rear-seat passengers increase the risk of death of belted drivers involved in serious crashes with at least one fatality. Methods: The information from every fatal crash in the United States between 1995 and 2001 was analyzed. Variables such as point of impact, restraint use, seat position, vehicle type, occupant age, gender, and injury severity were extracted from the Fatality Analysis Reporting System. Results: The odds of death for a belted driver seated directly in front of an unrestrained passenger in a serious head-on crash was 2.27 times higher (95% confidence interval [CI] = 1.94 to 2.66) than if seated in front of a restrained passenger. In contrast, a belted driver seated in front of an unrestrained passenger in a driver-side lateral-impact crash had no increase in mortality over a driver with a restrained rear-seat passenger (odds ratio, 0.8; 95% CI = 0.6 to 1.06). Logistic regression showed that passenger restraint, point of impact, vehicle type, passenger age, and driver age had a statistically significant influence on the outcome (death) of belted drivers. Adjusting for confounders (other than point of impact), the odds of fatality for a belted driver in a head-on crash was 2.28 times greater (95% CI = 1.93 to 2.7) with an unbelted rear-seat passenger. The unbelted rear-seat passenger also had an increased risk of death (odds ratio, 2.71; 95% CI = 2.44 to 3.01) when compared with restrained rear-seat passengers. Conclusions: Unrestrained rear-seat passengers place themselves and their driver at great risk of fatal injury when involved in a crash. [source] THE 1930s AND THE PRESENT DAY , CRISES COMPAREDECONOMIC AFFAIRS, Issue 4 2009Panagiotis Evangelopoulos Many analysts are comparing the deep crisis of our times with the crash of 1929 and the Great Depression that followed in the 1930s. They generally argue that Barack Obama is driving the world to recovery along Roosevelt's ,state superiority' line. Alas, today's crisis rings alarm bells for the manner in which we must manage the future of democracy, the state and markets. Markets cannot be ,ordered about' and when in the face of sound logic and practice an attempt is made to do just this, markets become refractory, or , even worse , they may collapse. [source] UK Assessment: How damaging would a housing market crash be for UK growth?ECONOMIC OUTLOOK, Issue 4 2004Article first published online: 14 OCT 200 No abstract is available for this article. [source] Paediatric lap-belt injury: A 7 year experienceEMERGENCY MEDICINE AUSTRALASIA, Issue 1 2006Michael Shepherd Abstract Objective:, To highlight the injuries that result from lap-belt use and make recommendations for prevention, the recent experience of a regional paediatric trauma centre was reviewed. Methods:, Retrospective review of admissions to Starship Children's Hospital from 1996 to 2003, with significant injury following involvement in a motor vehicle crash, while wearing a lap-belt. Patients were identified from two prospectively collected databases and discharge coding data. Results:, In total, 19 patients were identified over the 7 year period. The morbidity sustained includes 15 patients with hollow viscus injury, 13 laparotomies, 7 spinal fractures, 2 paraplegia and 1 fatality. A total of 11 patients required laparotomy with a median delay of 24 h. Of patients in the present series, 58% were aged less than 8 years and thus were inappropriately restrained. Conclusions:, Lap-belt use can result in a range of life-threatening injuries or permanent disability in the paediatric population. The incidence of serious lap-belt injury does not appear to be decreasing. Morbidity and mortality could be reduced by the use of three-point restraints, age appropriate restraints and booster seats. [source] The Effect of Seatbelt Use on Injury Patterns, Disposition, and Hospital Charges for EldersACADEMIC EMERGENCY MEDICINE, Issue 12 2002Andrew Coley MD Objective: To study the relationships between seatbelt use and injury patterns, hospital charges, morbidity, and mortality in elder motor vehicle crash victims. Methods: A retrospective review of individuals at least 65 years old presenting to an urban emergency department (ED) after a motor vehicle crash. Results: Over a two-year period, 339 patients had documentation of seatbelt use or non-use at the time of the crash. Of these, 241 (71%) patients had been wearing a seatbelt and 98 (29%) had not. Elders not using seatbelts were more likely to require hospitalization (29% unbelted vs. 17% belted) and had a higher mortality rate. Injury patterns were different in the two groups. Emergency department charges were significantly different between belted and unbelted elders ($351 vs. $451, p = 0.01) and head computed tomography (CT) utilization was higher in the unbelted group (25.6% vs 12.7%, p = 0.005). Conclusions: Improved seatbelt compliance in elders can reduce injuries, hospitalization rates, ED charges, and mortality resulting from motor vehicle crashes. [source] What Is an Asset Price Bubble?EUROPEAN FINANCIAL MANAGEMENT, Issue 1 2003An Operational Definition This paper reviews and analyses the current definitions of bubbles in asset prices. It makes the case that one cannot identify a bubble immediately, but one has to wait a sufficient amount of time to determine whether the previous prices can be justified by subsequent cash flows. The paper proposes an operational definition of a bubble as any time the realised asset return over given future period is more than two standard deviations from its expected return. Using this framework, the paper shows how the great crash of 1929 and 1987,both periods generally characterised as bubbles,prove not to be bubbles but the low point in stock prices in 1932 is a ,negative bubble.' The paper then extends this analysis to the internet stocks and concludes that it is virtually certain that it is a bubble. [source] A Comparison of Data Sources for Motor Vehicle Crash Characteristic AccuracyACADEMIC EMERGENCY MEDICINE, Issue 8 2000Robert J. Grant MD Abstract. Objective: To determine the accuracy of police reports (PRs), ambulance reports (ARs), and emergency department records (EDRs) in describing motor vehicle crash (MVC) characteristics when compared with an investigation performed by an experienced crash investigator trained in impact biomechanics. Methods: This was a cross-sectional, observational study. Ninety-one patients transported by ambulance to a university emergency department (ED) directly from the scene of an MVC from August 1997 to April 1998 were enrolled. Potential patients were identified from the ED log and consent was obtained to investigate the crash vehicle. Data describing MVC characteristics were abstracted from the PR, AR, and medical record. Variables of interest included restraint use (RU), air bag deployment (AD), and type of impact (TI). Agreements between the variables and the independent crash investigation were compared using kappa. Interrater reliability was determined using kappa by comparing a random sample of 20 abstracted reports for each data source with the originally abstracted data. Results: Agreement using kappa between the crash investigation and each data source was 0.588 (95% CI = 0.508 to 0.667) for the PR, 0.330 (95% CI = 0.252 to 0.407) for the AR, and 0.492 (95% CI = 0.413 to 0.572) for the EDR. Variable agreement was 0.239 (95% CI = 0.164 to 0.314) for RU, 0.350 (95% CI = 0.268 to 0.432) for AD, and 0.631 (95%= 0.563 to 0.698) for TI. Interrater reliability was excellent (kappa > 0.8) for all data sources. Conclusions: The strength of the agreement between the independent crash investigation and the data sources that were measured by kappa was fair to moderate, indicating inaccuracies. This presents ramifications for researchers and necessitates consideration of the validity and accuracy of crash characteristics contained in these data sources. [source] Option Expensing and Managerial Equity IncentivesFINANCIAL MARKETS, INSTITUTIONS & INSTRUMENTS, Issue 3 2009Yi Feng We examine the impact of mandatory option expensing on managerial equity incentives. Though effective only after June 15, 2005, there is evidence that U.S. firms begin preparing for option expensing as early as 2002 by making changes to their equity incentive plans. We find that (1) CEO option incentives exhibit a sharp reversal during the period 1993-2005, with the median CEO option incentives increasing 25% a year before 2002 but declining 17% a year after 2001; (2) the reduction in option incentives after 2001 is larger for firms that use excessive levels of equity incentives prior to 2002; (3) firms make similar reductions to options granted to CEOs, other top executives and lower-level employees; (4) CEO stock incentives increase throughout the entire 13-year period, rising at an even greater rate after 2001; and (5) the increase in stock incentives after 2001 is far from offsetting the corresponding decrease in option incentives. These findings are robust to controls for firm and CEO characteristics and for concurrent regulatory, business and market events such as the Sarbanes-Oxley Act of 2002, the option backdating scandal, and the 2000 stock market crash. We also provide a theoretical explanation for the documented changes in option incentives. [source] FROM EXCLUSIONARY COVENANT TO ETHNIC HYPERDIVERSITY IN JACKSON HEIGHTS, QUEENS,GEOGRAPHICAL REVIEW, Issue 4 2004INES M. MIYARES ABSTRACT. When Edward MacDougall of the Queensboro Realty Company originally envisioned and developed Jackson Heights in Queens, New York in the early twentieth century, he intended it to be an exclusive suburban community for white, nonimmigrant Protestants within a close commute of Midtown Manhattan. He could not have anticipated the 1929 stock market crash, the subsequent real estate market collapse, or the change in immigration policies and patterns after the 19505. This case study examines how housing and public transportation infrastructure intended to prevent ethnic diversity laid the foundation for one of the most diverse middle-class immigrant neighborhoods in the United States. [source] James Rogers and the Bristol slave trade*HISTORICAL RESEARCH, Issue 192 2003Kenneth Morgan This article examines the business failure of James Rogers, a large Bristol slave trader, within the context of the operation of the late British slave trade in west Africa, on the Middle Passage, and in the Caribbean. Based on a large cache of surviving manuscripts, the article shows that the credit crisis of 1793 led to the demise of Rogers's mercantile career but also that his business collapse stemmed from over-extending his slave trading activities, from relatively poor profit levels, and from attempts to expand his trading portfolio in the eighteen months before the national financial crash. [source] Clinical Utility of Office-Based Cognitive Predictors of Fitness to Drive in Persons with Dementia: A Systematic ReviewJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 12 2006Frank J. Molnar MDCM OBJECTIVES: To perform a systematic review of evidence available regarding in-office cognitive tests that differentiate safe from unsafe drivers with dementia. DESIGN: A comprehensive literature search of multiple databases including Medline, CINAHL, PsychInfo, AARP Ageline, and Sociofile from 1984 to 2005 was performed. This was supplemented by a search of Current Contents and a review of the bibliographies of all relevant articles. SETTING: English prospective cohort, retrospective cohort, and case-control studies that used accepted diagnostic criteria for dementia or Alzheimer's disease and that employed one of the primary outcomes of crash, simulator assessment, or on-road assessment were included. PARTICIPANTS: Two reviewers. MEASUREMENTS: The reviewers independently assessed study design, main outcome of interest, cognitive tests, and population details and assigned a Newcastle-Ottawa quality assessment rating. RESULTS: Sixteen articles met the inclusion criteria. Tests recommended by guidelines (e.g., the American Medical Association (AMA) and Canadian Medical Association guidelines) for the assessment of fitness to drive did not demonstrate robustly positive findings (e.g., Mini-Mental State Examination, Trails B) or were not evaluated in any of the included studies (e.g., Clock Drawing). Fifteen studies did not report any cutoff scores. CONCLUSION: Without validated cutoff scores, it is impossible to employ tests in a standardized fashion in front-line clinical settings. This study identified a research gap that will prevent the development of evidence-based guidelines. Recommendations to address this gap are that driving researchers routinely perform cutoff score analyses and that stakeholder organizations (e.g., AMA, American Geriatrics Society) sponsor consensus fora to review driving research methodologies. [source] Spatial variation in population growth rate and community structure affects local and regional dynamicsJOURNAL OF ANIMAL ECOLOGY, Issue 6 2008M. Kurtis Trzcinski Summary 1Theory predicting that populations with high maximum rates of increase (rmax) will be less stable, and that metapopulations with high average rmax will be less synchronous, was tested using a small protist, Bodo, that inhabits pitcher plant leaves (Sarracenia purpurea L.). The effects of predators and resources on these relationships were also determined. 2Abundance data collected for a total of 60 populations of Bodo, over a period of 3 months, at six sites in three bogs in eastern Canada, were used to test these predictions. Mosquitoes were manipulated in half the leaves partway through the season to increase the range of predation rates. 3Dynamics differed greatly among leaves and sites, but most populations exhibited one or more episodes of rapid increase followed by a population crash. Estimates of rmax obtained using a linear mixed-effects model, ranged from 1·5 to 2·7 per day. Resource levels (captured insect) and midge abundances affected rmax. 4Higher rmax was associated with greater temporal variability and lower synchrony as predicted. However, in contrast to expectations, populations with higher rmax also had lower mean abundance and were more suppressed by predators. 5This study demonstrates that the link between rmax and temporal variability is key to understanding the dynamics of populations that spend little time near equilibrium, and to predicting and interpreting the effects of community structure on the dynamics of such populations. [source] Wood thrush nest success and post-fledging survival across a temporal pulse of small mammal abundance in an oak forestJOURNAL OF ANIMAL ECOLOGY, Issue 4 2008Kenneth A. Schmidt Summary 1Synchronized mass production of seed crops, such as acorns, produces a resource pulse that may have far-reaching consequences for songbird populations through its effects on avian predators. Seed production in these forests represents only the first of several pulsed events. Secondary pulses emerge as mast-consuming rodents numerically respond to seed production and tertiary pulses emerge as generalist predators, such as raptors, numerically respond to rodents. In turn, these two groups reduce nest productivity and juvenile survivorship 1 and 2 years, respectively, after the initial pulse in seed production. 2At our study site in south-eastern New York, USA, autumn acorn abundance (primary pulse) largely determines rodent abundance (secondary pulse) the following spring. We tested the hypotheses that the population dynamics of a shrub-nesting passerine (wood thrush Hylocichla mustelina), is influenced by rodents through the: (a) direct effect of predation by rodents; (b) indirect effect of rodents on the abundance of raptors (tertiary pulse); and (c) indirect effect of rodent abundance on raptor diet. The latter specifically hypothesizes that a crash in the rodent population in the wake of region-wide failure of acorn production leads to an extreme diet shift in raptors that increases post-fledging mortality in birds. 3We conducted a 3-year study to examine variation in wood thrush nest success and fledgling survival, using radio telemetry, across a pulse of rodent abundance (i.e. low, medium and high). We also updated and reanalysed regional wood thrush population growth rates as a function of the annual variation in rodent abundance. 4Fledgling survivorship, but not nest success, varied in relation to annual rodent abundance. Raptors and eastern chipmunks Tamias striatus were the most commonly identified predators on fledglings. Fledgling survivorship was greatest at intermediate rodent abundance consistent with a shift in raptor diet. Regional rate of wood thrush population growth showed a unimodal relationship with rodent abundance, peaking during years with intermediate rodent abundance. This unimodal pattern was due to wood thrush population growth rates near or below zero during rodent population crashes. 5The telemetry study, pattern of regional abundance and synchronized population dynamics of coexisting thrushes suggest a common mechanism of behavioural changes in raptors in response to declines in rodent prey, which in turn affects thrush population dynamics. [source] Experimental evidence for costs of parasitism for a threatened species, White Sands pupfish (Cyprinodon tularosa)JOURNAL OF ANIMAL ECOLOGY, Issue 5 2004MICHAEL L. COLLYER Summary 1We used field and experimental data to test if white grub parasites (Diplostomatidae) are costly to White Sands pupfish (Cyprinodon tularosa), a threatened species restricted to four sites in the Chihuahuan desert, New Mexico. 2Of the four populations of C. tularosa, two are native and two are introduced. The two native populations (Malpais Spring and Salt Creek) are genetically distinct and have been isolated historically in dissimilar aquatic habitats (brackish spring and saline river, respectively). Two populations were established c. 1970 from translocation of Salt Creek fish to another saline river (Lost River) and another brackish spring (Mound Spring). 3Physid snails (Physidae) occur in the two brackish spring habitats but not the saline river habitats. These snails are first intermediate hosts for white grubs (Diplostomatidae). Therefore, the two freshwater populations are infected by diplostomatids. For the Mound Spring population, the ecological relationship of C. tularosa and diplostomatids has only recently occurred. 4In 1995, a population crash occurred for C. tularosa at Mound Spring, associated with a parasite outbreak. Diplostomatids were the presumptive cause of this crash, but this was inferred from observation of infection in collected fish. 5Two years of seasonal sampling of the two populations revealed that all collected fish were infected. Parasite intensities were significantly lower in winter compared to summer, suggesting that heavily infected fish were lost from the population on a seasonal basis. 6We conducted an artificial infection experiment to assess the costs of parasitism for previously uninfected C. tularosa females for various life-history traits. Under experimental conditions, diplostomatid infection caused increases in C. tularosa mortality and decreases in growth and fat storage. Individual-level costs of parasitism may translate to population-level patterns of parasitism for C. tularosa populations. Results from this study suggest that parasites may impact host overwinter survival, which is consistent with lower parasite intensities found during winters in wild populations. [source] Parametric intensity and the spatial arrangement of the terrestrial mollusc herbivores Deroceras reticulatum and Arion intermediusJOURNAL OF ANIMAL ECOLOGY, Issue 6 2000David A. Bohan Summary 1. Parametric intensity and spatial arrangement analyses were used to investigate the spatial pattern of the slugs Arion intermedius and Deroceras reticulatum. 2. The spatial lag of sampling (distance between sampling points) was shown to be unimportant in the intensity analyses. Rather, the 0·25 m grain scale was imposed on the whole sampling. The observed slope of the variance to mean relationships was common to both species, possibly determined by egg laying in batches at 0·25 m. However, the variance of the sample, for a given mean, was lower in summer. This corresponded with a reduction in the proportion of zero counts, which could be due to slug movement, possibly increased by predator activity, acting at the 0·25 m scale. 3. By contrast with the intensity analyses, the lag scale was important for spatial arrangement. At 0·25 m, in March 1997, the A. intermedius and D. reticulatum juveniles were aggregated, presumably about where egg batches were laid. At higher scales, the arrangements of D. reticulatum became spatially random, and A. intermedius resolved to a patch arrangement at the 16 m scale. 4. Over time, the D. reticulatum spatial arrangements remained random and independent of the previous sampling date. From March to July 1997, the A. intermedius patch persisted. A crash in abundance of both species, between July and October 1997, appeared to destroy the patch, but subsequent association suggested that the patch persisted until March 1998. The arrangements of the species were independent of one another on all sampling dates. 5. These species-specific spatial arrangements were independent of all measured environmental factors and consistent with differences in the local reproduction, survival and migration of A. intermedius and D. reticulatum. 6. This comparative study indicates that the terms aggregated, random and regular should have separate definitions for parametric intensity and spatial arrangement. Furthermore, spatial scale has different meaning in intensity and arrangement analyses. Spatial arrangements are not described by parametric intensity. Spatial arrangements change with spatial scale. Temporal changes in intensity need not manifest as changes in spatial arrangement. [source] An econometric model of nonlinear dynamics in the joint distribution of stock and bond returnsJOURNAL OF APPLIED ECONOMETRICS, Issue 1 2006Massimo Guidolin This paper considers a variety of econometric models for the joint distribution of US stock and bond returns in the presence of regime switching dynamics. While simple two- or three-state models capture the univariate dynamics in bond and stock returns, a more complicated four-state model with regimes characterized as crash, slow growth, bull and recovery states is required to capture their joint distribution. The transition probability matrix of this model has a very particular form. Exits from the crash state are almost always to the recovery state and occur with close to 50% chance, suggesting a bounce-back effect from the crash to the recovery state. Copyright © 2006 John Wiley & Sons, Ltd. [source] Depleted uranium,the growing concernJOURNAL OF APPLIED TOXICOLOGY, Issue 3 2002Aqel W. Abu-Qare Abstract Recently, several studies have reported on the health and environmental consequences of the use of depleted uranium. Depleted uranium is a heavy metal that is also radioactive. It is commonly used in missiles as a counterweight because of its very high density (1.6 times more than lead). Immediate health risks associated with exposure to depleted uranium include kidney and respiratory problems, with conditions such as kidney stones, chronic cough and severe dermatitis. Long-term risks include lung and bone cancer. Several published reports implicated exposure to depleted uranium in kidney damage, mutagenicity, cancer, inhibition of bone, neurological deficits, significant decrease in the pregnancy rate in mice and adverse effects on the reproductive and central nervous systems. Acute poisoning with depleted uranium elicited renal failure that could lead to death. The environmental consequences of its residue will be felt for thousands of years. It is inhaled and passed through the skin and eyes, transferred through the placenta into the fetus, distributed into tissues and eliminated in urine. The use of depleted uranium during the Gulf and Kosovo Wars and the crash of a Boeing airplane carrying depleted uranium in Amsterdam in 1992 were implicated in a health concern related to exposure to depleted uranium. Copyright © 2002 John Wiley & Sons, Ltd. [source] Age of Drinking Onset and Injuries, Motor Vehicle Crashes, and Physical Fights After Drinking and When Not DrinkingALCOHOLISM, Issue 5 2009Ralph W. Hingson Background:, Earlier age of drinking onset has been associated with greater odds of involvement in motor vehicle crashes, unintentional injuries, and physical fights after drinking. This study explores whether early drinkers take more risks even when sober by comparing potential associations between age of drinking onset and these outcomes after drinking relative to when respondents have not been drinking. Method:, From a national sample, 4,021 ever-drinkers ages 18 to 39 were asked age of drinking onset, not counting tastes or sips. They were also asked if they were ever in motor vehicle crashes, unintentionally injured, or in physical fights after drinking and when not drinking. GEE logistic regression models for repeated measures dichotomous outcomes compared whether odds ratios between age of onset and these adverse outcomes significantly differed when they occurred after drinking versus when not drinking, controlling for respondents' demographic characteristics, cigarette and marijuana use, family history of alcoholism, ever experiencing alcohol dependence, and frequency of binge drinking. Results:, Compared with persons who started drinking at age 21+, those who started at ages <14, 14 to 15, 16 to 17, and 18 to 20 had, after drinking, respectively greater odds: 6.3 (2.6, 15.3), 5.2 (2.2, 12.3), 3.3 (1.5, 7.3), and 2.2 (0.9, 5.1) of having been in a motor vehicle crash; 6.0 (3.4, 10.5), 4.9 (3.0, 8.6), 3.7 (2.4, 5.6), and 1.9 (1.2, 2.9) of ever being in a fight; and 4.6 (2.4, 8.7), 4.7 (2.6, 8.6), 3.2 (1.9, 5.6), and 2.3 (1.3, 4.0) of ever being accidentally injured. The odds of experiencing motor vehicle accidents or injuries when not drinking were not significantly elevated among early onset drinkers. The odds of earlier onset drinkers being in fights were also significantly greater when respondents had been drinking than not drinking. Conclusion:, Starting to drink at an earlier age is associated with greater odds of experiencing motor vehicle crash involvement, unintentional injuries, and physical fights when respondents were drinking, but less so when respondents had not been drinking. These findings reinforce the need for programs and policies to delay drinking onset. [source] Factors influencing Soay sheep survivalJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES C (APPLIED STATISTICS), Issue 4 2000E. A. Catchpole We present a survival analysis of Soay sheep mark recapture and recovery data. Unlike previous conditional analyses, it is not necessary to assume equality of recovery and recapture probabilities; instead these are estimated by maximum likelihood. Male and female sheep are treated separately, with the higher numbers and survival probabilities of the females resulting in a more complex model than that used for the males. In both cases, however, age and time aspects need to be included and there is a strong indication of a reduction in survival for sheep aged 7 years or more. Time variation in survival is related to the size of the population and selected weather variables, by using logistic regression. The size of the population significantly affects the survival probabilities of male and female lambs, and of female sheep aged 7 or more years. March rainfall and a measure of the North Atlantic oscillation are found to influence survival significantly for all age groups considered, for both males and females. Either of these weather variables can be used in a model. Several phenotypic and genotypic individual covariates are also fitted. The only covariate which is found to influence survival significantly is the type of horn of first-year female sheep. There is a substantial variation in the recovery probabilities over time, reflecting in part the increased effort when a population crash was expected. The goodness of fit of the model is checked by using graphical procedures. [source] Fatal Injuries of US Citizens AbroadJOURNAL OF TRAVEL MEDICINE, Issue 5 2007Clare E. Guse MS Background US citizens are increasingly traveling, working, and studying abroad as well as retiring abroad. The objective of this study was to describe the type and scope of injury deaths among US citizens abroad and to compare injury death proportions by region to those in the United States. Methods A cross-sectional design using reports of US citizen deaths abroad for 1998, 2000, and 2002 on file at the US State Department was employed. The main outcome measures were the frequencies of injury deaths and proportional mortality ratios (PMRs) comparing deaths abroad to deaths in the United States. Results Two thousand eleven injury deaths were reported in the 3 years, comprising 13% of all deaths. The overall age-adjusted PMR for injury fatalities abroad compared to the United States was 1.6 (95% confidence interval 1.6,1.7). The highest age-adjusted PMRs for motor vehicle crashes were found in Africa (2.7) and Southeast Asia (1.6). The proportion of drowning deaths was elevated in all regions abroad. Conclusions Injuries occur at a higher proportion abroad than in the United States. Motor vehicle crash and drowning fatalities are of particular concern. Improved data quality and surveillance of deaths would help government agencies create more evidence-based country advisories. [source] | |||||||||||||||||||||||||||||||