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211.

Introduction

Self-screening by older drivers has shown considerable promise for increasing self-awareness about functional abilities associated with safe driving. The purpose of this study was to improve upon existing self-screening instruments by focusing entirely on “health concerns” that affect driving - that is, the symptoms that people experience due to medical conditions and the medications used to treat them - rather than the medical conditions or medications themselves.

Method

A computer-based, easy-to-use self-screening instrument for older drivers was developed to provide individualized feedback intended to increase self-awareness about declines in driving-related abilities, as well as suggestions for behavioral changes or safety tips to maintain safe driving, further evaluation from a physician/health professional, and vehicle modifications to help compensate for driving-related declines.

Results

This paper describes the development of the self-screening instrument and summarizes findings relative to increasing self-awareness among older drivers. This research represents an important first step in improving self-awareness among older drivers through self-screening.  相似文献   
212.
Fires in agricultural ecosystems emit greenhouse gases and aerosols that influence climate on multiple spatial and temporal scales. Annex 1 countries of the United Nations Framework Convention on Climate Change (UNFCCC), many of which ratified the Kyoto Protocol, are required to report emissions of CH4 and N2O from these fires annually. In this study, we evaluated several aspects of this reporting system, including the optimality of the crops targeted by the UNFCCC globally and within Annex 1 countries, and the consistency of emissions inventories among different countries. We also evaluated the success of individual countries in capturing interannual variability and long-term trends in agricultural fire activity. In our approach, we combined global high-resolution maps of crop harvest area and production, derived from satellite maps and ground-based census data, with Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) measurements of active fires. At a global scale, we found that adding ground nuts (e.g., peanuts), cocoa, cotton and oil palm, and removing potato, oats, rye, and pulse other from the list of 14 crops targeted by the UNFCCC increased the percentage of active fires covered by the reporting system by 9%. Optimization led to a different recommended list for Annex 1 countries, requiring the addition of sunflower, cotton, rapeseed, and alfalfa and the removal of beans, sugarcane, pulse others, and tuber-root others. Extending emissions reporting to all Annex 1 countries (from the current set of 19 countries) would increase the efficacy of the reporting system from 6% to 15%, and further including several non-Annex 1 countries (Argentina, Brazil, China, India, Indonesia, Thailand, Kazakhstan, Mexico, and Nigeria) would capture over 55% of active fires in croplands worldwide. Analyses of interannual trends from the United States and Australia showed the importance of both intensity of fire use and crop production in controlling year-to-year variations in agricultural fire emissions. Remote sensing provides an effective means for evaluating some aspects of the current UNFCCC emissions reporting system; and, if combined with census data, field experiments and expert opinion, has the potential to improve the robustness of the next generation inventory system.  相似文献   
213.
Natural protected areas (NPA) are portions of the Mexican territory where the original environment has not been modified and which are protected in order t  相似文献   
214.
Regional Environmental Change - Most studies of major disasters focus on the impacts of the event and the short-term responses. Some evaluate the underlying causes of vulnerability, but few...  相似文献   
215.
This study aimed at relating the variability of Ni biogeochemistry along the ultramafic toposequence to pedogenesis and soil mineralogy. Hypereutric Cambisols dominate upslope; Cambic Vertisols and Fluvic Cambisols occur downslope. The soil mineralogy showed abundance of primary serpentine all over the sequence. It is predominant upslope but secondary smectites dominate in the Vertisols. Free Fe-oxides are abundant in all soils but slightly more abundant in the upslope soils. Whereas serpentines hold Ni in a similar and restricted range in every soil (approx. 0.3 %), Ni contents in smectites may vary a lot and Mg-rich and Al-poor smectites in the Vertisol could hold up to 4.9 % Ni. Ni was probably adsorbed onto amorphous Fe-oxides and was also exchangeable in secondary smectites. High availability of Ni in soils was confirmed by DTPA extractions. However, it varied significantly along the toposequence, being higher in upslope soils, where Ni-bearing amorphous Fe-oxides were abundant and total organic carbon higher and sensibly lower downslope on the Vertisols: NiDTPA varied from 285 mg kg?1 in the surface of soil I (upslope) to 95.9 mg kg?1 in the surface of Fluvic Cambisols. Concentration of Ni in Alyssum murale shoots varied from 0.7 % (Hypereutric Cambisols) to 1.4 % (Hypereutric Vertisol). Amazingly, Ni uptake by A. murale was not correlated to NiDTPA, suggesting the existence of specific edaphic conditions that affect the ecophysiology of A. murale upslope.  相似文献   
216.
Vulnerabilities to floods in Thailand are changing as a result of many factors. Formal and informal institutions help shape exposure, sensitivity and capacities to respond of individuals, social groups and social-ecological systems. In this paper we draw on several case studies of flood events and flood-affected communities to first assess how current practices reflect various laws, procedures, programs and policies for managing floods and disasters and then explore the implications for dealing with additional challenges posed by climate change. Our analysis identifies several institutional traps which need to be overcome if vulnerability is to be reduced, namely capture of agendas by technical elites, single-level or centralized concentration of capacities, organizational fragmentation and overemphasis on reactive crisis management. Possible responses are to expand public participation in managing risks, build adaptive capacities at multiple levels and link them, integrate flood disaster management and climate change adaptation into development planning, prioritize risk reduction for socially vulnerable groups and strengthen links between knowledge and practice. Responses like these could help reduce vulnerabilities under current climate and flood regimes, while also improving capacities to handle the future which every way that unfolds.  相似文献   
217.
Sediment samples were collected from two homes which were flooded in the wake of Hurricane Katrina in August 2005. The samples were analyzed for trace metals and semi-volatile organic compounds using techniques based on established EPA methods. The data showed higher concentrations of some metals and semi-volatile organic pollutants than reported in previous outdoor sampling events of soils and sediments. The Lake Pontchartrain sediments became resuspended during the hurricane, and this material subsequently was found in the residential areas of New Orleans following levee breaches. The clay and silt particles appear to be selectively deposited inside homes, and sediment contaminant concentrations are usually greatest within this fraction. Re-entry advisories based on outdoor sample concentration results may have under-predicted the exposure levels to homeowners and first responders. All contaminants found in the sediment sampled in this study have their origin in the sediments of Lake Pontchartrain and other localized sources.  相似文献   
218.
Reproductive success and development of F2 offspring from F1 adult African clawed frogs (Xenopus laevis) exposed to atrazine throughout larval development and as sexually mature adults was examined. Larval X. laevis were exposed to one of four nominal concentrations of atrazine (0, 1, 10, 25 microg atrazine/l) beginning 96 hr after fertilization and continuing through two years post-metamorphosis. Clutch size and survival of offspring were used as measurement endpoints to gauge reproductive success of the F1 frogs. Larval survivorship and time to metamorphosis were used to gauge developmental success of the F2 offspring from atrazine-exposed frogs. Testes in F1 and F2 frogs were examined for incidence of anomalies, such as testicular ovarian follicles, and sex ratios in F2 offspring were investigated to determine if exposure to atrazine caused trans-generational effects (effects on F2 individuals due to exposure of F1 individuals). There were no effects of any of the studied concentrations of atrazine on clutch size of F1 frogs. There were also no effects on hatching success or time to metamorphosis. Sex ratios did not differ between F2 offspring among treatments. There was no evidence to suggest a transgenerational effect of atrazine on spawning success or reproductive development of X. laevis. This is consistent with the presence of robust populations of X. laevis in areas where they are exposed to atrazine that has been used for several decades for weed control in production of corn. Our observations also are consistent with the results of most other studies of frogs where no effects were found to be associated with exposure to atrazine. Our data do not support the hypothesis that atrazine significantly affects reproductive fitness and development of frogs.  相似文献   
219.
220.
A mortality event of Cladocora caespitosa corals and the extent of bleaching, necrosis and pigmented areas in the colonies were studied at the southeastern coast of Cyprus during a prolonged period of higher than average sea temperature anomalies (summer/autumn 2012). With the use of scuba diving and image analysis software, we monitored the extent of mortality of 29 colonies of C. caespitosa by measuring and comparing the area percentage of healthy tissue, affected tissue (bleached, necrotic) and older mortality events (encrusted skeleton). In September 2012, on average, 24 % of the colonies surface area was affected (bleaching and/or necrosis). In October 2012, C. caespitosa showed on average 26.3 % of the colony surface area affected, evidence of continuing deterioration. At the same time, 10 % (3 of 29) of the colonies showed an increase in the pigmentation of previously bleached polyps in small and marginal areas (6–8 %). Irrespective of the amount, the regaining of pigments recorded is considered an important find. Corals and marine organisms in general in the Levantine Sea are affected greatly by warming events, to the extent where a very small percentage of polyps/colonies show resilience under thermal stress. Natural bleaching of C. caespitosa, even though limited to a few colonies and very small portions of tissue/polyps, was documented for the first time in the Levantine Sea. We conclude that temperature anomalies are associated with the mortality event. Whether prolonged higher temperature is the direct cause, or whether it acts synergistically with other factors should be the subject of further investigations.  相似文献   
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