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991.
The job demands-resources (JD-R) model was tested in a study among 3,092 employees working in 1 of 4 different home care organizations. The central assumption in the model is that burnout develops when certain job demands are high and when job resources are limited because such negative working conditions lead to energy depletion and undermine worker motivation and learning opportunities, respectively. A series of multigroup structural equation modeling analyses provide strong evidence for the JD-R model. Specifically, results showed that job demands are primarily and positively related to the exhaustion component of burnout, whereas job resources are primarily related to cynicism (negatively) and professional efficacy (positively). The theoretical and practical implications of the JD-R model are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
The primary visual sources of depth and size information are binocular cues and motion parallax. Here, the authors determine the efficacy of these cues to control prehension by presenting them in isolation from other visual cues. When only binocular cues were available, reaches showed normal scaling of the transport and grasp components with object distance and size. However, when only motion parallax was available, only the transpont component scaled reliably. No additional increase in scaling was found when both cues were available simultaneously. Therefore, although equivalent information is available from binocular and motion parallax information, the latter may be of relatively limited use for the control of the grasp. Binocular disparity appears selectively important for the control of the grasp. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
993.
The purpose of this paper was twofold: (1) to determine jobs/tasks associated with current injury, illness, and fatality trends in the electrical contracting sector of the construction industry; and (2) to identify current safety practices associated with the prevention of these injuries, illnesses, and fatalities. To achieve the project objectives, a survey was designed and sent to Michigan electrical contractors. To design an adequate survey, the research team first collected background information using the U.S. Bureau of Labor Statistics online database, published research, and contractor interviews. This paper presents and discusses the results of this study.  相似文献   
994.
Out-of-Plane Strengthening of Masonry Walls with Reinforced Composites   总被引:3,自引:0,他引:3  
This paper presents an investigation into the effectiveness of using fiber-reinforced composite overlays to strengthen existing unreinforced masonry walls to resist out-of-plane static loads. A total of fifteen wall panels [1,200 × 1,800 × 200 mm (4 ft × 6 ft × 8 in.)] were tested. Twelve panels were assembled with fiber-reinforcing systems attached to the tension side, and the remaining three control walls were left without any external reinforcement. Two configurations of external reinforcement were evaluated. The first reinforcement configuration consisted of two layers of fiber-reinforced plastic webbing and the second consisted of vertical and horizontal bands of undirectional fiber composites. The three wall specimens without external reinforcement were tested to evaluate the change in the system strength and behavior with application of the external reinforcing systems. In addition to the two fiber configurations, the testing program also evaluated two methods of surface preparation of the walls, sand blasting, and wire brush. All specimens were thoroughly washed by water jet, 48 hours prior to application of the fiber-reinforcing systems. Three specimens were tested for each variable. A uniformly distributed lateral load was applied to each panel using the procedures described in the ASTM Standard E-72 Test Method (airbag). Failure loads, strains in the external reinforcement (FRP), out-of-plane deformations, and failure modes were recorded. Recommendations on the usefulness of the proposed technique as a means of strengthening masonry walls for out-of-plane loads are presented. In general, flexural strength of masonry walls can be increased if the shear failure is controlled.  相似文献   
995.
This paper describes an analytical model of filtration for granular media, based on the mechanics of particle migration under hydraulic loads. A new equation to predict the probability of particle movement through a 3D network model of the filter voids has been developed. Void constriction sizes are determined based on the particle-size distribution and relative density of the filter. An important new development is the differentiation between particles that form part of the filter structure and fine particles that are loose within the filter voids, or coarse particles that are enmeshed in a matrix of fines. The rate of particle erosion and transport is governed by the consideration of mass and momentum conservation. The model describes the time-dependent change of flow rate and base and filter particle-size distribution, porosity, and permeability. The model has application in the design of granular filters for noncohesive uniform, well-, and broadly graded base and filter materials.  相似文献   
996.
This research examined alcohol-induced motivation to drink as a factor that contributes to preoccupation with drinking. Forty undergraduates rated their degree of preoccupation with drinking. The author determined the relationship between the undergraduates' preoccupation and the degree to which alcohol primed their motivation to drink by having them rate their desire for alcohol after they consumed a dose of alcohol or a placebo. Results showed that individual differences in preoccupation were predicted by the priming effects displayed after alcohol was consumed. More preoccupied individuals reported greater priming effects. Priming effects following placebo were minimal and were not related to preoccupation. The research shows that reinforcing effects of alcohol may contribute to cognitive preoccupation with drinking and promote patterns of alcohol abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
The current study examined binge drinking among high school students over an academic year. Adolescent drinkers (N?=?621; 58% female) were grouped into 4 trajectories: drinkers (35%), increasers (14%), decreasers (16%), and persistent binge drinkers (35%). Prospective analyses indicated several factors that predicted escalation and de-escalation of binge drinking. Increasers were more likely to regularly use alcohol and cigarettes at a younger age than drinkers. Compared with decreasers, persistent binge drinkers reported regular alcohol and marijuana use at younger ages. Lower levels of perceived student drinking appeared to be a protective factor for onset of binge drinking. The results highlight the need to study precursors to the naturally occurring fluctuations in binge drinking and suggest factors that may accentuate the risk of binge drinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
The job demands-resources (JD-R) model proposes that working conditions can be categorized into 2 broad categories, job demands and job resources, that are differentially related to specific outcomes. A series of LISREL analyses using self-reports as well as observer ratings of the working conditions provided strong evidence for the JD-R model: Job demands are primarily related to the exhaustion component of burnout, whereas (lack of) job resources are primarily related to disengagement. Highly similar patterns were observed in each of 3 occupational groups: human services, industry, and transport (total N?=?374). In addition, results confirmed the 2-factor structure (exhaustion and disengagement) of a new burnout instrument—the Oldenburg Burnout Inventory—and suggested that this structure is essentially invariant across occupational groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
Anterior communicating artery (ACoA) aneurysm rupture can lead to an anterograde amnesia syndrome similar to that observed after damage to the hippocampus and medial temporal lobes (MT). It is currently believed that ACoA amnesia results from basal forebrain damage that disrupts hippocampal processing without direct hippocampal damage. Converging evidence from animal studies and computational modeling suggests that qualitative differences may exist in the pattern of memory impairment after basal forebrain or MT damage. For example, animals with basal forebrain but not hippocampal damage are impaired at delay eyeblink classical conditioning (EBCC). In this study, individuals with ACoA amnesia were shown to be impaired at delay EBCC compared with matched controls; this contrasts with the spared delay EBCC previously observed in MT amnesia. This finding suggests the beginning of a possible dissociation between the memory impairments in MT versus ACoA amnesia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
A reconceptualization of stigma is presented that changes the emphasis from the devaluation of an individual's identity to the process by which individuals who satisfy certain criteria come to be excluded from various kinds of social interactions. The authors propose that phenomena currently placed under the general rubric of stigma involve a set of distinct psychological systems designed by natural selection to solve specific problems associated with sociality. In particular, the authors suggest that human beings possess cognitive adaptations designed to cause them to avoid poor social exchange partners, join cooperative groups (for purposes of between-group competition and exploitation), and avoid contact with those who are differentially likely to carry communicable pathogens. The evolutionary view contributes to the current conceptualization of stigma by providing an account of the ultimate function of stigmatization and helping to explain its consensual nature. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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