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A novel, pathogenic presenilin 1 (PS1) mutation has recently been identified in a large Aboriginal kindred living in dispersed communities throughout British Columbia, Canada. Disseminating genetic information and ensuring that appropriate genetic counseling services are provided to all concerned relatives have posed several unique challenges. These challenges include knowledge exchange and continuity of care in a geographically remote and culturally distinct community. To our knowledge, this is the first time a specific genetic counseling approach has been needed for early-onset familial Alzheimer disease (EOFAD) in a North American Aboriginal community.  相似文献   
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Despite prevalent concerns about the ethical conduct of clinical trials, little is known about the day-to-day work of trials and the ethical challenges arising in them. This paper reports on a study designed to fill this gap and demonstrates a need to refine the oversight system for trials to reflect an understanding of this day-to-day work. It also illuminates ethical challenges that cannot be addressed by the oversight system and so necessitate a rethinking of the ethics of clinical trials.  相似文献   
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Science policy mandates across the industrialized world insinuate more active roles for publics, their earlier participation in policy decisions, and expanded notions of science and technology governance. In response to these policies, engaged scholars in science studies have sought to design and conduct exercises aimed at better attuning science to its public contexts. As demand increases for innovative and potentially democratic forms of public engagement with science and technology, so also do the prospects for insights from science studies to contribute to policy agendas and institutional capabilities. This collection brings together an international set of scholars in science, technology and society who inquire into the meaning, efficacy and responsibility of engaged science studies scholarship as a public matter.  相似文献   
265.
Autonomous agents are not so difficult to construct. Constructing autonomous agents that will work as required is much harder. A clear way in which we can design and analyse autonomous systems so that we can be more confident that their behaviour is as required is to use formal methods. These can, in principle, allow us to exactly specify the behaviour of the agent, and verify that any implementation has the properties required. In addition to using a more formal approach, it is clear that problems of conceptualisation and analysis can be aided by the use of an appropriate abstraction.In this article we tackle one particular aspect of formal methods for agent-based systems, namely the formal representation and implementation of deliberation within agents. The key aspect here is simplicity. Agents are specified using a relatively simple temporal logic and are executed by directly interpreting such temporal formulae. Deliberation is captured by modifying the way in which execution handles its temporal goals. Thus, in this article we provide motivations, theoretical underpinnings, implementation details, correctness arguments, and comparisons with related work.  相似文献   
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We examined whether midazolam impairs short-term/working memory processes. We hypothesize that prior dissociations in midazolam's effects on short-term/working memory tasks and episodic memory tasks arise because midazolam has a larger effect on episodic memory processes than on short-term/working memory processes. To examine these issues, .03 mg/kg of participant's bodyweight of midazolam was administered in a double-blind placebo-controlled within-participant design. Performance on the digit span and category generation/recall tasks was examined. The results of Experiment 1 demonstrated that: (1) midazolam impaired performance on the digit span task; (2) midazolam did not impair performance on the category generation task; (3) midazolam impaired performance on the category recall task; and (4) midazolam's effect on category recall was four times as large as its effect on digit span. The results of Experiment 2 demonstrated that midazolam did not impair digit span performance when the digit span task was administered at a later time. These results suggest that midazolam can impair short-term/working memory processes, but these effects are substantially smaller than midazolam's effect on episodic memory processes. Moreover, they demonstrate that conscious awareness of materials during study is not sufficient to produce episodic memory.  相似文献   
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Several studies have demonstrated that divided attention at encoding significantly reduces memory performance, whereas divided attention at retrieval affects memory performance only minimally. However, the possibility exists that retrieval processes have shown such resilience because the concurrent tasks used have often not been very demanding. To assess this possibility, we used independent manipulations of the concurrent task during either encoding or retrieval that included stimulus-response compatibility and participant- versus experimenter-controlled pace. In addition, we manipulated the distribution of practice that the participants received with the primary and the concurrent tasks. The results replicated and extended those recently reported by Rohrer and Pashler (2003), indicating that although memory performance is negatively affected by divided attention at retrieval, especially with noncompatible stimulus-response mapping in the concurrent task, this effect was much smaller than that at encoding, in line with the asymmetry notion. Furthermore, experimenter versus participant control of the concurrent task had no effect on memory retrieval. Finally, under conditions of equal practice with both the memory and the concurrent tasks, memory retrieval was affected only to a small degree. In contrast to encoding processes, the processes involved in retrieval accuracy appear, in many cases, to be less interrupted by divided attention, although this protection requires substantial resources.  相似文献   
270.
Functional analysis results for multiple topographies of aberrant behavior were graphed in an aggregate fashion and then separately for 48 clients. The results indicated that multiple topographies of behavior may be maintained by different contingencies. These results indicate that graphing functional analysis data in an aggregate fashion and then separately may improve the accuracy of their interpretation.  相似文献   
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