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161.
Critical Flicker Fusion Thresholds (CFFTs) were measured in 644 elderly people identified from community-based general practice records, and the relationship of CFFT with age was investigated. The CFFT was measured using the method of limits with mean scores for three ascending (flicker/fusion) and three descending (fusion/flicker) presentations being recorded. The difference between the ascending and descending means was found to be significantly correlated with age (r=−0.131,P<0.001) and may reflect a reduced sensitivity of the Central Nervous System to suprathreshold flicker with increasing age. The results suggest that CFFT measurement has an important role to play in gerontological research as an objective measure of cognitive aspects of the ageing process.  相似文献   
162.
In this article the perspective shifts to the “upstream” end of the agricultural knowledge and information system (AKIS). Because knowledge policy and strategic decision-making are not the prerogative of the public sector, organizations such as cooperative unions and multinational companies are included. After considering the influence of the changing environment on the nature of the AKIS, the role of knowledge management and policy in the emerging knowledge and information market is examined. Special attention is given to public and private R&D. The article then looks where information technology (IT) fits in and what considerations determine strategic investment in IT projects and sustained services. Some of the European experiences with this strategic investment are evaluated.  相似文献   
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164.
Abstract— In our discussion of the articles in this Special Section, we ask how well the various methods employed in these investigations can be made to converge on a common issue. We review how current evidence from positron emission tomography, studies of event-related potentials, cognitive methods, lesion studies, and network models relates to the mental processing of an ambiguous word. While many puzzles remain, we are impressed by the promising possibility of bringing these different methods together to deal with an issue central to cognition.  相似文献   
165.
Private and public sector managers were compared regarding their job characteristics and organizational commitment. We hypothesized that job characteristics would be positively related to commitment and that sector would moderate that relationship. Moderated regression analyses revealed partial support for both hypotheses. The existence of clarity and challenge were positively related to commitment. Job characteristics demonstrated a stronger relationship with commitment among private sector managers. Explanations for these findings and directions for future research are discussed.  相似文献   
166.
167.
When subjects attempt to fake psychopathology on the MMPI, scores on subtle subscales tend to be lower than those of nonfaking subjects. Our study hypothesized that this paradox comes about because the subtle subscales have no predictive validity, but their face validity for psychopathology is the opposite of the keyed direction for psychopathology. Subjects who attempt to fake psychopathology do so on the basis of item content and thus achieve lower rather than higher scores. Three groups of 80 undergraduates took the MMPI under regular, faking-good, or faking-bad instructions. As expected, faking-bad subjects scored significantly lower than regular subjects on the 100 most subtle items, and this was due to their responses to those. 73 of the items whose face validity was misleading. The results are consistent with other work showing valid uses of subtle items in detecting deception.  相似文献   
168.
Because rheumatoid arthritis (RA) has a more unpredictable course than osteoarthritis (OA), we hypothesized that generalized expectancies (optimistic/ pessimistic) influence the psychosocial adjustment of RA patients, whereas disease severity influences the adjustment of OA patients. Path analysis (LISREL VI) revealed that pessimistic RA patients (N= 107) and the more physically disabled OA patients (N= 108) reported poorer adjustment. The hypothesized mediating role of coping was supported for the RA but not the OA sample; that is, pessimism was associated with poor adjustment through greater use of wishful thinking coping. Unexpectedly, problem-solving coping was not found to mediate the optimism adjustment relationship.  相似文献   
169.
Two studies examined the consequences of turnover, by investigating factors affecting the job satisfaction of people who remain (i. e., stayers) in response to a coworker (i. e., leaver) who departed for a better job. Consistent with Tesser and Campbell's (1983) self-esteem maintenance model, three factors were found to influence the job satisfaction level of stayers: (a) the extent to which they compared their job situation to the leaver's new one, which was negatively related to stayers’ level of satisfaction, (b) the relevance of the leaver to the stayer for social comparison purposes, which was negatively related to the stayers’ level of satisfaction, and (c) the stayers’ trait self-esteem, which was positively related to the stayers’ level of job satisfaction. Theoretical implications, limitations, and future research directions are discussed.  相似文献   
170.
The Family Factors Field Study of Operation Desert Shield/Storm (ODS) was designed to collect data on the impact of the Persian Gulf deployment on soldier/family well-being, and the effectiveness of Army and community resources in assisting and supporting families of deployed soldiers. In October 1990, a task force was assembled, and multi-agency research teams visited several Army installations. Informal individual and group interviews were conducted with spouses, unit family support leaders, unit rear detachment personnel, garrison leaders, and local Army program/service providers. The questions were aimed at identifying key stressors which spouses and children experienced in relation to the sudden deployment, as well a stress mediators such as social supports and personal coping skills. Anecdotal information collected during the site visits, combined with findings from previous research on Army families, was used to develop a questionnaire designed to quantify those variables which emerged as relevant to a study of stressors and stress mediators in the context of the ODS deployment.  相似文献   
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