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The present study, based on 158 HIV seropositives and 167 HIV seronegatives, demonstrates that saliva collected with the Omni-SAL device and tested with GACELISA (an IgG antibody capture ELISA) is an effective non-invasive alternative to serum for anti-HIV IgG antibody screening. The study also shows that a conventional serum Western blot kit can be used, with slight modifications, for confirmatory testing of saliva specimens. Collecting saliva with the Omni-SAL device had a very good acceptance rate among Tanzanian subjects, and although this diagnostic method is not yet known by the general public, 65% of the study participants preferred to give saliva instead of blood for HIV testing.  相似文献   
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Shannon’s entropy plays an important role in the context of information theory. Since this entropy is not applicable to a system which has survived for some units of time, the concept of residual entropy has been developed in the literature. Here we generalize the residual entropy by choosing a convex function ? with ?(1) = 0. In this paper, some orderings and aging properties have been defined in terms of the generalized residual entropy function and their properties have been studied. Quite a few results available in the literature have been generalized and some distributions (viz. uniform, exponential, Pareto, power series, finite range) have been characterized through the generalized residual entropy.  相似文献   
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In the verified architecture microprocessor (VAMP) project we have designed, functionally verified, and synthesized a processor with full DLX instruction set, delayed branch, Tomasulo scheduler, maskable nested precise interrupts, pipelined fully IEEE compatible dual precision floating point unit with variable latency, and separate instruction and data caches. The verification has been carried out in the theorem proving system PVS. The processor has been implemented on a Xilinx FPGA. A shorter version of this article with the title “Instantiating uninterpreted functional units and memory system: functional verification of the VAMP” appeared in [8]. The work reported here was done while all the authors were with Saarland University.  相似文献   
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Examined how the factors relative in-group size and relative outgroup size (i.e., minority vs. nonminority) affect the perception of in-group and out-group homogeneity. On the basis of social identity theory, we hypothesized that (a) members of minorities would perceive the in-group as more homogeneous than the out-group, whereas members of nonminorities would perceive the reverse; (b) this effect would be strongest on dimensions most strongly correlated with the social categorization; and (c) members of minorities would identify more strongly with their in-group than would members of nonminorities. 192 13–15 yr olds participated in the experiment. On the presumed basis of a perceptual task, approximately half were randomly allocated to minimal social categories, which differed in perceived size relative to an out-group (which also differed in perceived size). They were asked to estimate the homogeneity of the two groups on a number of dimensional attributes. The remaining (control) subjects gave similar estimates under identical conditions, except that they were not allocated to a category. The data confirmed all but the second hypothesis, which was only partially supported. The results were interpreted in terms of social identification processed. Results tend to rule out alternative explanations in terms of an inverse relation between group size and perceived group homogeneity, rating extremity, and in-group favoritism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Examined the job performance of 420 credit managers (mean age at hiring 25 yrs) from a large finance company who either quit their job, were fired, or were promoted to a higher position in the company. Six biographical variables and 12 performance appraisal scores accumulated from data in employee files were used in a cross-validated multiple discriminant analysis to predict membership in the 3 classification groups. Results reveal a systematic relation between the performance appraisal variables and the classification groups: The performance of promoted Ss was significantly superior to that of Ss who quit, which in turn was significantly superior to the performance of the fired Ss. 18 discriminating variables accounted for a 46.7% hit rate in group membership. Findings are discussed in the context of research on performance antecedents of voluntary and involuntary turnover, as well as the feedback properties of performance appraisal information. It is suggested that no single performance–turnover relation exists. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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