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291.
Objective: The Useful Field of View (UFOV) assessment, a measure of visual speed of processing, has been shown to be a predictive measure of motor vehicle collision (MVC) involvement in an older adult population, but it remains unknown whether UFOV predicts commercial motor vehicle (CMV) driving safety during secondary task engagement. The purpose of this study is to determine whether the UFOV assessment predicts simulated MVCs in long-haul CMV drivers.

Method: Fifty licensed CMV drivers (Mage = 39.80, SD = 8.38, 98% male, 56% Caucasian) were administered the 3-subtest version of the UFOV assessment, where lower scores measured in milliseconds indicated better performance. CMV drivers completed 4 simulated drives, each spanning approximately a 22.50-mile distance. Four secondary tasks were presented to participants in a counterbalanced order during the drives: (a) no secondary task, (b) cell phone conversation, (c) text messaging interaction, and (d) e-mailing interaction with an on-board dispatch device.

Results: The selective attention subtest significantly predicted simulated MVCs regardless of secondary task. Each 20 ms slower on subtest 3 was associated with a 25% increase in the risk of an MVC in the simulated drive. The e-mail interaction secondary task significantly predicted simulated MVCs with a 4.14 times greater risk of an MVC compared to the no secondary task condition. Subtest 3, a measure of visual speed of processing, significantly predicted MVCs in the email interaction task. Each 20 ms slower on subtest 3 was associated with a 25% increase in the risk of an MVC during the email interaction task.

Conclusions: The UFOV subtest 3 may be a promising measure to identify CMV drivers who may be at risk for MVCs or in need of cognitive training aimed at improving speed of processing. Subtest 3 may also identify CMV drivers who are particularly at risk when engaged in secondary tasks while driving.  相似文献   

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Stable nitrogen isotope ratios are routinely used to trace the dispersion and assimilation of wastewater-derived N in receiving environments, but few isotope studies have investigated wastewater treatment plants and ponds themselves. An improved understanding of N isotope compositions in effluent will help assess treatment plant processes and performance and will help trace sources of excess nutrients in receiving environments. Here, we assess N budgets and treatment processes in seven wastewater treatment plants and wastewater stabilisation ponds in northern Australia based on concentrations and isotope ratios of N in effluent. We show that δ15N values in effluent are linked to treatment type, effectiveness of conversion of ammonia and levels of gaseous N emissions. These relationships suggest that N isotope monitoring of wastewater treatment plants and ponds can provide an integrated assessment of treatment performance and gaseous N emissions on a pond- or plant-wide scale that is not readily available through other methods. Our findings further imply that monitoring N isotope ratios in receiving environments cannot be assumed to be universally effective as their sensitivity to uptake of wastewater-derived N will vary with the characteristics of individual treatment systems. Paradoxically, N isotope monitoring is less effective where treatment systems are functioning poorly and where monitoring needs are the greatest.  相似文献   
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Grapsoid crabs of the genera Planes and Plagusia are commonly referred to as “rafting crabs” due to their propensity to live on flotsam and pelagic marine animals. Planes minutus and Planes major (=Planes cyaneus) are epibionts of sea turtles. Occurrences of grapsoid crabs in the genera Planes and Plagusia were evaluated on a total of 27 olive ridley sea turtles, Lepidochelys olivacea, from the eastern tropic Pacific (1998–2001) and the Hawaiian Islands (2002) captured in July–December each year. This is the first report of Planes marinus and Plagusia squamosa on sea turtles, and of P. major, P. marinus, and P. squamosa in sympatry on a confined substrate. Stomach content analyses showed P. major and P. marinus consumed a variety of neuston and marine vegetation, with the former consuming considerably more animal material. Epibiotic P. squamosa consumed mostly plant material. The three Planes species had distinctive differences in gastric mill tooth morphology. The versatile mouthparts of P. marinus are described and resemble those of their congeners. Most female P. major and P. marinus collected were ovigerous and present in all survey months.  相似文献   
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This paper recognises the need for a revision of watershed development policy in India in relation to the planning of development interventions involving agricultural intensification and rainwater harvesting and the need for new approaches to assist the planning process. Building on, and using as an example, the results of biophysical and societal impact studies carried out on two watershed development projects in Karnataka three new management/dissemination tools, are suggested. These are (1) the web-based geographical information systems exploratory, climate land assessment and impact management tool dissemination tool for disseminating to policymakers and non-specialist stakeholders the downstream impacts of watershed interventions, (2) the ‘quadrant’ approach for ensuring that sustainability criteria are met and (3) Bayesian networks to investigate the biophysical and societal impacts of interventions. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue  相似文献   
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Preimplantation genetic diagnosis (PGD) for monogenic diseases has known a considerable evolution since its first application in the early 1990s. Especially the technical aspects of the genetic diagnosis itself, the single-cell genetic analysis, has constantly evolved to reach levels of accuracy and efficiency nearing those of genetic diagnosis on regular DNA samples. In this review, we will focus on the molecular biological techniques that are currently in use in the most advanced centers for PGD for monogenic disorders, including multiplex polymerase chain reaction (PCR) and post-PCR diagnostic methods, whole genome amplification (WGA) and multiple displacement amplification (MDA). As it becomes more and more clear that when it comes to ethically difficult indications, PGD goes further than prenatal diagnosis (PND), we will also briefly discuss ethical issues. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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