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This investigation focused on the interrelationships among students' study activities, students' self-concept of academic ability ratings, students' academic achievement, and instructional practices in 12 high school biology courses. Using a framework derived from a previous investigation, course features were classified into those that appear to (a) place demands on, (b) support, or (c) compensate for student engagement in particular study activities. Students' study activities, self-concept of academic ability ratings, and achievement were measured with experimenter-developed instruments. Results are reported for (a) characteristics of instruments and course features, (b) relationships between central factors of the investigation, and (c) multi-level relationships between course features and student variables. Results at the student level indicated that self-concept of academic ability and, to a lesser extent, students' study activities were positively associated with student achievement. Students' self-concept of academic ability ratings were also linked to students' engagement in generative, proactive study activities. At the course level the supportive practices of providing challenging homework assignments and extensive feedback on student coursework were associated with student engagement in effortful, generative, proactive study activities. The provision of extensive feedback was also associated with high student achievement. Multi-level relationships were analysed using hierarchical linear modelling (HLM) analyses. These analyses revealed, for example, that in courses in which little or no feedback is given on homework assignments, the relationship between achievement and student engagement in diligent effort management activities was enhanced. Other HLM analyses were conducted to examine the mediating role of course features on the relationship between students' self-concept of academic ability and their study activities and achievement. For example, the presence of challenging course demands was associated with an enhancement of the relationship between self-concept of academic ability and achievement whereas the presence of instructor provisions (supports and compensations) designed to reduce course demands was associated with a reduction in this relationship.  相似文献   
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Predictive testing for Huntington disease is presently offered in a select few medical genetics centers in the United States. This is in part due to the labor intensive counseling and psychological testing suggested by the research protocols. We discuss some specific suggestions for establishing programs for Huntington disease predictive testing within pre-existing medical genetics clinics to encourage more centers to offer presymptomatic testing. This will allow more at risk individuals the opportunity to consider predictive testing and cut down the expenses of traveling to the few predictive testing centers that currently exist. The counseling principals will remain similar to those discussed here, even following the identification of the Huntington disease mutation.  相似文献   
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The strict competence hypothesis has sparked a small dialogue among several researchers attempting to understand its ramifications for human sentence processing and incremental interpretation in particular. In this paper, we review the dialogue, reconstructing the arguments in an attempt to make them more uniform and crisp, and provide our own analyses of certain of the issues that arise. We argue that strict competence, because it requires a synchronous computation mechanism, may actually lead to more complex, rather than simpler, models of incremental interpretation. Asynchronous computation, which is arguably both psychologically more plausible and conceptually more basic, allows for incremental interpretation to fall out naturally, without additional machinery for interpreting partial constituents. We show that this is true regardless of whether the presumed interpretation mechanism is top-down or bottom-up, contra previous conclusions in the literature, and propose a particular implementation of some of these ideas using a novel representation based on tree-adjoining grammars.The research in this paper was supported in part by grant IRI-9157996 from the National Science Foundation to the first author. The authors would like to thank Fernando Pereira, Edward Stabler, and Mark Steedman for discussions on the topic of this paper and for their comments on previous drafts.  相似文献   
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