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31.
Helmets significantly decrease morbidity and mortality from motorcycle crashes, but many areas of the world lack universal helmet laws. To educate motorcyclists in areas without helmet laws, more knowledge of motorcyclists’ helmet beliefs is needed.A web-based survey was therefore designed to assess motorcyclists’ attitudes, norms and behaviors towards helmets in a U.S. state with a limited helmet law. Of 445 survey respondents, 68.4% of respondents reported always wearing a helmet. The not-always-helmeted riders were more likely than the always-helmeted to be male; to bave less education; and to have a history of previous motorcycle crashes and injuries. Although both groups had taken rider training classes, fewer of the not-always-helmeted had learned how to ride in a class. The strongest correlates of being not-always-helmeted (vs. always-helmeted) were attitudes that helmets were not protective and impaired sight/hearing; and the normative belief that they would only wear helmets if forced by law. Because attitudes are often more easily changed than normative beliefs, education may increase helmet use. However, less than half of riders in this state with a mandatory education program learned how to ride from a rider education course, and 44% of non-helmeted said they would only wear a helmet if forced by law. Legislation may therefore be a more efficient and effective strategy than education to increase helmet use.  相似文献   
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Examined the way the sex and race of the rater and the sex and race of the ratee influence assessments of ratee performance on a simulated work-sampling task. 36 undergraduates assumed the role of a manager and rated all 8 combinations of male-female and black-white performers. Results indicate that sex-race stereotypes do influence assessments of behavior on a work-sampling task even when objective measures are defined. Findings are discussed in terms of potential methods of overcoming these biases to use more effectively the work samples for selection and promotion decisions are discussed. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This study sought to characterize the effects of removing the nuclei of primary importance in relaying the thalamic head direction signal to the hippocampal formation (the anterior dorsal [AD] and lateral dorsal [LD] nuclei) on the performance of a variety of spatial and nonspatial tasks. The results indicate that combined excitotoxic lesions of the AD and LD nuclei produce marked deficits on a variety of spatial tasks. These tasks included T-maze alternation and the ability to locate a hidden platform set at a fixed distance and fixed direction from a beacon in a Morris water maze. Although object recognition appeared unaffected, marked impairments were found in the ability to detect when an object was placed in a novel position (object-in-place memory). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The Haemocell S-350 device has recently been introduced for intraoperative autotransfusion. The system uses a novel membrane filter to process shed blood. In the first part of this study a 0.2-micron pore size filter was used in a randomized trial comparing the use of autotransfusion (n = 8) with bank blood controls (n = 9) during aortic reconstruction. This part of the trial was abandoned because of unexpected non-surgical bleeding. Bank blood requirements fell from a median of 3.0 (range 0.0-9.0) units to 1.5 (range 0.0-7.0) units when autotransfusion was used, but these patients had a greater perioperative blood loss (1791 (range 932-3104) versus 1140 (range 440-3840) ml). There was evidence of postoperative heparin excess with an activated partial thromboplastin time ratio of 1.3 (range 0.9-3.0) versus 1.0 (range 1.0-1.2) in controls and an activated clotting time of 206 (range 143-280) versus 137 (range 107-142) s. This was confirmed by raised plasma heparin levels and a prolonged thrombin time normalized by protamine. To improve performance a 0.6-micron pore size filter was studied in ten patients. Filtration efficiency doubled from 19 to 38 per cent. Electron micrographs demonstrated better filter clearance, but 44 per cent of the original concentration of heparin remained in the reinfusate. The S-350 device may be an attractive alternative to centrifugation for intraoperative autotransfusion but, until efficiency is improved, it should only be used for cardiovascular surgery when excess heparin can be reversed with protamine.  相似文献   
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The authors, Nigel Isaacs, Michael Donn and Dr George Baird of the School of Architecture, Victoria University of Wellington, present a succinct account of the practical difficulties they encountered when implementing recommendations from energy audits in a defined number of New Zealand schools. It is concluded that these difficulties relate more to funding and personnel than the engineering of the energy savings in themselves.  相似文献   
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A neural network algorithm-based system that reads handwritten ZIP codes appearing on real US mail is described. The system uses a recognition-based segmenter, that is a hybrid of connected-components analysis (CCA), vertical cuts, and a neural network recognizer. Connected components that are single digits are handled by CCA. CCs that are combined or dissected digits are handled by the vertical-cut segmenter. The four main stages of processing are preprocessing, in which noise is removed and the digits are deslanted, CCA segmentation and recognition, vertical-cut-point estimation and segmentation, and directly lookup. The system was trained and tested on approximately 10000 images, five- and nine-digit ZIP code fields taken from real mail  相似文献   
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