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51.
Medical networks offer discounted fees, control of the workers' compensation case, quality monitoring, and managed care services. As channeling of workers' compensation cases to networks increases, credentialed physicians will benefit.  相似文献   
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It was proposed that individuals' responses to information regarding their relative position in a performance distribution would depend on how they frame the information. To the degree that they focus selectively on the positive features of the feedback (i.e., the number of others who performed worse than them) rather than the negative features (i.e., the number of others who performed better than them) they should report higher ability levels and more positive affective reactions. In Study I, Ss received feedback indicating that they occupied a particular percentile standing in either a large or small distribution. Individuals with negative orientations (depressives and pessimists) reported lower ability levels as a function of increases in comparison group size, whereas individuals with positive orientations (nondepressives and optimists) reported higher ability levels. Presumably, these effects occurred because negatively oriented persons focused on the negative features of the feedback and positively oriented persons focused on the positive features of the feedback. The results of Study 2 support this explanation. Implications for the social comparison literature are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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地域通信网的干扰技术研究   总被引:1,自引:0,他引:1  
本文在分析地域通信网结构及组成的基础上,研究了对地域通信网实施的节点破坏、末端信息封锁、局部阻塞瘫痪等对抗方法,并使用干扰地域通信网的程度、节点干扰率、末端节点封锁率和传递信息误差率等指标对干扰效果进行评估。  相似文献   
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The Rescorla-Wagner model has been the most influential theory of associative learning to emerge from the study of animal behavior over the last 25 years. Recently, equivalence to this model has become a benchmark in assessing connectionist models, with such equivalence often achieved by incorporating the Widrow-Hoff delta rule. This article presents the Rescorla-Wagner model's basic assumptions, reviews some of the model's predictive successes and failures, relates the failures to the model's assumptions, and discusses the model's heuristic value. It is concluded that the model has had a positive influence on the study of simple associative learning by stimulating research and contributing to new model development. However, this benefit should neither lead to the model being regarded as inherently "correct" nor imply that its predictions can be profitably used to assess other models. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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'Borderline' methicillin-resistant Staphylococcus aureus (MRSA) strains are inhibited by drug concentrations of 2 to 8 micrograms/mL. This type of resistance is usually mediated by 'hyper beta-lactamase' production which is detectable in vitro by susceptibility to combinations of a beta-lactam and a beta-lactamase inhibitor (ie, amoxicillin and clavulanic acid). A survey of Canadian infection control experts was performed to assess the knowledge, attitudes and beliefs regarding the containment requirements for borderline MRSA strains in acute health care facilities. Twenty-three of 38 Canadian infection control experts (61%) (members of the Canadian Hospital Epidemiology Committee [CHEC] or the Society for Healthcare Epidemiology of American [SHEA]) returned a questionnaire about a fictional patient with a postoperative wound infection with such a strain. Eleven respondents (48%) considered the isolate as an MRSA, 11 did not and one was unsure. All who did not believe the strain to be MRSA would not have isolated or cohorted the patient. Four in the latter group would have isolated the patient if he or she were on a neurosurgery or cardiovascular surgery unit, indicating a desire to restrict spread of this isolate on those units. Seven of the 12 individuals who had managed at least one patient with a borderline MRSA did not advocate patient isolation or cohorting, and five did. This survey has supported the belief that there are discrepancies among infection control decision-makers in Canada regarding the approach, precautions and therapy of patients infected with borderline strains of MRSA. Further data on virulence of and effective therapy for these isolates are needed to assess whether the additional cost is warranted in controlling the nosocomial spread of these isolates.  相似文献   
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Diffusion induced grain boundary migration (DIGM) was observed to occur in a Ni-48.5 wt pct Cu alloy during oxidation at 450 °C, 500 °C, 600 °C, and 707 °C in air. The DIGM zones are Cu enriched. A Ni depleted zone, consisting of small recrystallized grains, formed in the matrix beneath the metal-oxide interface during oxidation at 600 °C and 707 °C. This process is referred to as oxidation-induced recrystallization (OIR). Growth of the small OIR grains was observed to be associated with Cu-rich DIGM. No Cu-rich DIGM was found in the same alloy when annealed in Ar at 707 °C. Oxidation of this alloy in air resulted in the formation of a duplex oxide: an inner NiO layer and an outer CuO layer. The NiO layer was observed to grow at a faster rate than the CuO layer. The occurrence of Cu-rich DIGM is interpreted in terms of this preferential oxidation of Ni.  相似文献   
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