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71.
The C. elegans mutants, lrn-1 and lrn-2, are impaired in associative learning using conditioned taste cues. Both mutants are defective in associative learning about appetitive and aversive events, indicating that lrn-1 and lrn-2 exert effects across motivational boundaries. In a new olfactory associative learning paradigm, in which wild type worms learn to avoid a previously attractive diacetyl odor after it has been paired with an aversive acetic acid solution, lrn-1 and lrn-2 are impaired. Although defective in associative learning using a conditioned olfactory cue, nonassociative learning (habituation and dishabituation) using this same olfactory cue is unaffected. The discovery that lrn-1 and lrn-2 are defective in associative learning with both taste and olfactory cues may suggest that associative learning in different sensory modalities converges on a common genetic pathway in C. elegans that is subserved by lrn-1 and lrn-2. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The study used quantitative and qualitative measures to determine differences in learning outcomes between two sections of an advanced technical writing course taught by the same instructor. The instructor used traditional textbook methods in one and technology-enhanced methods in the other. The findings upheld those of previous studies in that students in the experimental group rated both the course and their learning higher than that of their counterparts in the control group. Although fewer significant differences than expected resulted from the many measures taken, substantive positive differences in the writing submitted by students in the experimental group did occur. In order for such changes in performance to emerge as statistically significant differences, evaluation criteria for technical communication students may need to change  相似文献   
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In two experiments, learning disabled adolescents read passages that described North American minerals, using materials that incorporated either mnemonic or nonmnemonic illustrations. In Experiment 1, the students were instructed to remember attribute dichotomies (e.g., hard vs. soft minerals), whereas in Experiment 2, the students had to remember specific attribute values (e.g., Hardness Levels 1–20). In both experiments, students learned significantly more when they studied passages with mnemonic pictures. This was true both on immediate performance tests (Experiments 1 and 2) and following a 1-week delay (Experiment 2). Moreover, in Experiment 2, mnemonic instruction facilitated student's ability to make correct inferences about attribute dichotomies—even though such information was never explicitly presented in the lesson. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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COTS software products are increasingly becoming standard components for building integrated information systems. At the same time, the growth of electronic trading, turbulent market conditions, and a project-style approach to business have created a demand for information systems that can be rapidly adapted to changing business process demands. However, the ongoing development of COTS products is unpredictable as their developers and source code are rarely available. Flexible information systems use COTS components because they cost-effectively supply required component functionality. A software architecture can capture a system design as a set of interacting components and capture the role of COTS software in "implementing" certain components.  相似文献   
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Examines the ethical issues facing psychologists working with people who are infected with AIDS (acquired immune deficiency syndrome) and individuals in high-risk groups. Duty to treat is examined with a consideration of homophobia and biases about intravenous drug users. Confidentiality is discussed in the context of record keeping, in cases of conflict with duty to warn, and in cases of suicide. Psychologists are urged to consider possible ethical dilemmas before they arise, to ensure that the best decisions are made. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We compared the impacts of stocking age-0 Atlantic salmon (Salmo salar) at high and low densities, and no stocking on abundance and growth of age-0 rainbow trout (Oncorhyncus mykiss) in Barnum House Creek, Ontario during 1993 to 2005. A similar stream, Shelter Valley Creek, was chosen as an appropriate reference stream where age-0 Atlantic salmon were not stocked. The catches of age-0 rainbow trout in Barnum House and the reference stream were highly correlated (r = 0.96) during years when no stocking occurred; however, this relationship did not persist in years when Atlantic salmon were stocked. The catch of age-0 rainbow trout in Barnum House Creek was significantly lower under both high (P = 0.00026) and low (P = 0.011) density Atlantic salmon stocking treatments compared with the no stocking treatment. The catches of age-0 rainbow trout and age-0 Atlantic salmon were negatively correlated in Barnum House Creek (r = −0.63). The length of age-0 rainbow trout in Barnum House Creek was depressed significantly (P = 0.004), under the high intensity Atlantic salmon stocking treatment, but not under the low intensity treatment (P = 0.20). In contrast, the length of age-0 rainbow trout in Shelter Valley Creek was unchanged over the same period. Restoration stocking of Atlantic salmon in Lake Ontario tributaries may impact rainbow trout abundance and growth.  相似文献   
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