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861.
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863.
In this study, academic task assignments were modified in an effort to improve the conduct and task performance of three students with emotional and behavioral disorders. Functional assessments, including interviews and direct observations, were conducted to identify variables that affected the performance of each student during problematic assignments. The assessments implicated several variables for each student. These variables were then used as guides to modify the problematic tasks. The modifications resulted in reduced levels of problem behaviors and increased rates of task engagement, work productivity and accuracy for each of the students. The effects were demonstrated within ongoing academic activities and replicated through the use of reversal designs. The findings are discussed in relation to the practical process of functional assessment and the relevance of curricular and instructional arrangements to the occurrence of disruptive behavior.  相似文献   
864.
The feminist ethic of care has often been criticized for its inability to address four problems--the problem of exploitation as it threatens care givers, the problem of sustaining care-giver integrity, the dangers of conceiving the mother-child dyad normatively as a paradigm for human relationships, and the problem of security social justice on a broad scale among relative strangers. We argue that there are resources within the ethic of care for addressing each of these problems, and we sketch strategies for developing the ethic more fully.  相似文献   
865.
Feminist legal theory provides a healthy skepticism toward legal doctrine and insists that we reexamine even formally gender-neutral rules to uncover problematic assumptions behind them. The article first outlines feminist legal theory from the perspectives of liberal, cultural, and radical feminism. Examples of how each theory influences legal practice, case law, and legislation are highlighted. Each perspective is then applied to a contemporary bioethical issue, egg donation. Following a brief discussion of the common themes shared by feminist jurisprudence, the article incorporates a narrative reflecting on the integration of the common feminist themes in the context of the passage of the Maryland Health Care Decisions Act. The article concludes that gender does matter and that an understanding of feminist legal theory and practice will enrich the analysis of contemporary bioethical issues.  相似文献   
866.
The World-Wide Web provides an inviting opportunity to reach large numbers of people, both as an audience for psychoacoustical discussions and demonstrations and as subjects for psychoacoustical experiments. Such use of the Web poses a unique set of challenges. We present the methodologies used to prepare a multimedia primer in auditory perception at McGill University. As well as instructional material, this primer includes acoustical experiments conducted over the Web. We discuss the response and experiences with this site in general and in a particular class situation at Hanover College.  相似文献   
867.
This article reports of the activities of the working group, Ethics & Engineers, of the Royal Flemish Society of Engineers. More particularly, the ethical problems that engineers face in the preparation of an environmental report are illuminated. Irrespective to which party the engineer belongs, he or she is confronted with the difficult weighting of his or her personal interest, the interests of private companies and last but not least the common good. It is argued that the implementation of a code of ethics and the introduction of courses on engineering ethics into the education of engineers would strengthen the engineer in the fulfilment of his vocation. Dirk Holemans is a bio-engineer preparing a doctoral thesis on the social responsibility of engineers, Herman Lodewyckx teaches ethics and has research interests in professional and applied ethics.  相似文献   
868.
The aim of these experiments was to determine whether impaired retention performance in aversively motivated tasks, induced by blockade of amygdala AMPA receptors, is due to influences on mechanisms underlying memory retrieval or to other influences on performance. Rats received either footshock escape training (1 or 10 trials), or no foot shock, in a two-compartment straight alley and bilateral intra-amygdala infusions of the AMPA receptor antagonist CNQX (0.5 μg) were subsequently administered prior to inhibitory avoidance retention testing 8 days later. The CNQX impaired, but did not block, inhibitory avoidance retention performance as indicated by the initial latencies to enter the shock compartment. The animals were then retained in the alley until they remained in the starting compartment for 100 consecutive s and entries into the shock compartment were recorded as errors. In both the controls and CNQX-treated groups, increases in amount of original training resulted in fewer errors, indicating memory for the escape training. Furthermore, regardless of the amount of original training (i.e., 0, 1, or 10 trials), CNQX-treated groups made more errors. Other experiments examined intra-amygdala CNQX effects on reactivity to footshock, locomotor activity, and anxiety. CNQX decreased reactivity to footshock, blocked shock-induced decreases in locomotor activity, and had an anxiolytic effect in an elevated plus maze comparable to that induced by midazolam (0.5 μg). These findings suggest that intra-amygdala infusions of CNQX prior to retention testing affect inhibitory avoidance retention performance following aversive training by altering locomotor activity, reducing sensitivity to footshock, and reducing anxiety. The implications of these findings for hypotheses concerning amygdala function in aversively motivated learning and memory is discussed.  相似文献   
869.
This paper makes the assumption that organ transplantation is, under some conditions at least, a proper use of communal medical resources. Proceeding from this assumption, the author: (1) sketches the history of the problem; (2) briefly examines the prevalent models of communal structure and offers an alternate version; (3) discusses notions of justice and obligation derived from these different models; (4) applies these to the practice of harvesting organs for transplantation; and then (5) offers a different process for harvesting organs from the newly dead. If community is viewed as united by a set of shred goals and common values among which the value of community itself is important, then certain reciprocal obligations among members obtain. I suggest that routine salvage of organs from the newly dead be instituted but that it be routine salvage “with a twist”: rather early in life all members of the community are given the opportunity to refuse but their refusal carries the reciprocal condition that they cannot later become the recipients of that which they refuse to others.  相似文献   
870.
An aftereffect of perceived texture density contingent on the color of a surrounding region is reported. In a series of experiments, participants were adapted, with fixation, to stimuli in which the relative density of two achromatic texture regions was perfectly correlated with the color presented in a surrounding region. Following adaptation, the perceived relative density of the two regions was contingent on the color of the surrounding region or of the texture elements themselves. For example, if high density on the left was correlated with a blue surround during adaptation (and high density on the right with a yellow surround), then in order for the left and right textures to appear equal in the assessment phase, denser texture was required on the left in the presence of a blue surround (and denser texture on the right in the context of a yellow surround). Contingent aftereffects were found (1) with black-and-white scatter-dot textures, (2) with luminance-balanced textures, and (3) when the texture elements, rather than the surrounds, were colored during assessment. Effect size was decreased when the elements themselves were colored, but also when spatial subportions of the surround were used for the presentation of color. The effect may be mediated by retinal color spreading (Pöppel, 1986) and appears consistent with a local associative account of contingent aftereffects, such as Barlow’s (1990) model of modifiable inhibition.  相似文献   
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