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841.
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The purpose of this study was to test theoretical propositions advanced by Meyer and Herscovitch (2001) concerning the interactive effects of affective, normative, and continuance commitment on focal (staying intentions) and discretionary (citizenship) behavior. Study measures were gathered from a sample of 545 hospital employees. Several a priori predictions regarding commitment profile differences were confirmed. Significant three-way interactions were found for both staying intentions and citizenship behavior. The pattern of relations for both behavioral criteria partially confirmed the hypotheses, but also provided evidence of possible “context effects” whereby the meaning and implications of the commitment components varies as a function of the other components. These effects were most notable for normative commitment and may offer new insight into the nature of this construct. Implications for commitment theory and its application were discussed.  相似文献   
844.
mRNA translation, or protein synthesis, is a major component of the transformation of the genetic code into any cellular activity. This complicated, multistep process is divided into three phases: initiation, elongation, and termination. Initiation is the step at which the ribosome is recruited to the mRNA, and is regarded as the major rate-limiting step in translation, while elongation consists of the elongation of the polypeptide chain; both steps are frequent targets for regulation, which is defined as a change in the rate of translation of an mRNA per unit time. In the normal brain, control of translation is a key mechanism for regulation of memory and synaptic plasticity consolidation, i.e., the off-line processing of acquired information. These regulation processes may differ between different brain structures or neuronal populations. Moreover, dysregulation of translation leads to pathological brain function such as memory impairment. Both normal and abnormal function of the translation machinery is believed to lead to translational up-regulation or down-regulation of a subset of mRNAs. However, the identification of these newly synthesized proteins and determination of the rates of protein synthesis or degradation taking place in different neuronal types and compartments at different time points in the brain demand new proteomic methods and system biology approaches. Here, we discuss in detail the relationship between translation regulation and memory or synaptic plasticity consolidation while focusing on a model of cortical-dependent taste learning task and hippocampal-dependent plasticity. In addition, we describe a novel systems biology perspective to better describe consolidation.  相似文献   
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846.
Hodkinson  Ian 《Studia Logica》2002,72(2):185-197
We prove decidability of satisfiability of sentences of the monodic packed fragment of first-order temporal logic with equality and connectives Until and Since, in models with various flows of time and domains of arbitrary cardinality. We also prove decidability over models with finite domains, over flows of time including the real order.  相似文献   
847.
Quality of life (QOL) is increasingly assessed in cancer patients. In this article, the authors examined the psychometric performance of a commonly used QOL questionnaire, the Quality of Life Questionnaire--Cancer 30 (QLQ-C30; N. K. Aaronson et al., 1993), in multiethnic cancer patients. Content validation studies in patients and clinicians identified possible new items. Multiple-group confirmatory factor analysis supported equivalent structure across ethnic groups (Caucasians and Asian/Pacific Islanders [APIs]). A higher order QOL factor appeared to directly affect functioning scales and symptom count. Exploratory factor analysis examined effects of new items. Ten factors were extracted, 6 consistent with the original instrument and 4 reflecting potentially new aspects of QOL: Positive Social Support, Coping, Existential Well-Being, and Sexuality/Intimacy. The QLQ-C30 appears appropriate for use in API cancer patients. Further work needs to ensure that it includes all important domains.  相似文献   
848.
Two experiments are reported in which subjects were required to name the color in which letter strings were printed. In the first experiment, color-naming latencies were the same when the letter strings were pseudohomophones of color words (e.g., PINC) as when they were color names (e.g., PINK). Both these conditions produced slower responses than control strings matched with the pseudohomophones for visual similarity to the color word (e.g., PINN). Unlike the first experiment, the second included trials in which the ink color was congruent with the color to which the letter string was related. The results with incongruent stimuli paralleled those in the first experiment. With the congruent stimuli, however, responses were faster with color words than with either their pseudohomophones or control strings, which were equally slow. It is proposed that phonological recoding occurs relatively slowly but cannot be suppressed even when it harms performance.  相似文献   
849.
In two experiments, 330 3‐ to 4‐year‐olds competed for stickers in a game in which the optimal response strategy was to point to an empty box that their opponent would receive in order to obtain a baited box for themselves. When the baited box contained stickers, children showed a strong tendency to point at the baited box and therefore lose the stickers to their opponent. In Experiment 1 children performed better when the number of stickers to be won was represented with one of five different types of symbol: numerals, number words, dots, a photograph or sweets. In Experiment 2 children transferred their improved performance in symbolic conditions to non‐symbolic conditions. These findings suggest that symbols enable children to formulate an efficient response strategy, and that this effect may be qualitatively different in children from the effect of symbols in non‐human primates.  相似文献   
850.
In longitudinal studies data is collected in a series of waves. Each wave after the first suffers from attrition. Therefore it can be difficult to discriminate between changes in sample parameters due to a longitudinal process (e.g. ageing) and changes due to attrition. The problem is particularly vexing if one of the purposes is to compare differences between two or more groups over time, because there may be differential attrition across groups. We refer to this as a recruitment problem, because the sample studied in any wave after the first can be thought of as having been recruited from a preceding wave. We present a mathematical model of the recruitment process. We then apply it to two large longitudinal studies, the British Cohort Survey 1970 and the National Child Development Study (1958), to demonstrate how we can identify effects expected from recruitment alone. As an illustration we show that differential recruitment would predict increasing differences between estimates of men's and women's intelligence as the studied sample ages.  相似文献   
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