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951.
Increases in the oscillation frequency of bimanual movements produce a switch from an anti-phase (180° relative phase) to an in-phase (0° relative phase) coordination pattern. This finding is observed when subjects are instructed not to intervene when they feel themselves slipping out of the anti-phase pattern. The question addressed in this study concerned how performance would be affected if subjects were instructed to try to maintain the pattern at all times. This issue was addressed using two separate groups of subjects: one group was given the do not intervene instructions, the other group was told to try to stay with the pattern at all times. Forearm rotations were tested in 15 s trials, paced by an auditory metronome set at 1.0, 1.5, 2.0, 2.5, and 3.0 Hz. Frequency distributions of the point estimates of relative phase were analyzed. The Do not Intervene group replicated previous findings, as indicated by the development of a bimodal histogram of relative phase distributions with increases in oscillation frequency. However, a very different pattern of findings emerged with increases in oscillation frequency for the group told to stay with the anti-phase pattern. Rather than a bimodal distribution being developed, the data maintained 180° as its central tendency — no secondary distribution developed around 0° relative phase. These data suggest that volitional control can over-ride the inherent dynamical tendencies of the motor system.  相似文献   
952.
The contributions to this Special Issue illustrate research on several important types of environmental units, including psychiatric and substance abuse treatment programs, neighborhood block groups, and entire communities. They also exemplify alternative methodologies, such as assessing environments by relying on participants' appraisals, external observers' ratings, historical archives, and direct observation. I draw on these contributions and some of my own work to discuss four recurrent issues: (a) how to conceptualize environmental domains and dimensions; (b) how to understand environmental dynamics, that is, the interplay of environmental factors both within one setting and across settings; (c) how to comprehend the processes that link environmental factors to outcomes, especially with respect to the power and evanescence of environmental influence; and (d) how to use information about environments to monitor and improve them. Increased knowledge in these four areas is essential to help fulfill a major aim of community psychology: to understand social processes and improve intervention program outcomes.  相似文献   
953.
In this study it was determined whether (a) classification as opposed to absence of classification has an effect on the quality of clinical hypotheses (b) the DSM-III-R and the CBCL have a different effect on the quality of clinical hypotheses, and (c) the potential difference between the DSM-III-R and the CBCL is moderated by the different number of syndromes identified by these systems. To investigate these questions, an experiment was conducted in which 86 clinicians generated hypotheses for six cases. The clinicians were divided into a DSM-III-R, a CBCL, and a control group. Of the six cases, two were classified by both classification systems as one syndrome, two were classified as one syndrome by the DSM-III-R but as two syndromes by the CBCL, and two were classified as two syndromes by the DSM-III-R but as one syndrome by the CBCL. The quality of the hypotheses was determined by means of four dependent variables selected from an overview of qualitative criteria: explanatory value, redundancy, possibility of operationalization, and specificity. No differences between the CBCL and the control groups were found. The DSM group performed better than the control group regarding explanatory value and redundancy. The DSM-III-R group also scored better than the CBCL group regarding explanatory value, particularly when the number of identified syndromes was two for the CBCL and one for the DSM-III-R.  相似文献   
954.
Christians in the Holy Land, and particularly members of the monastic communities in the Judean desert, were the first to compose original works of theology in Arabic. These writers presented the doctrines of the church in an idiom which was calculated to appeal to the understanding of any speaker of Arabic who was familiar with the Qur'an and with the thought of the early Muslim mutakallimin. From these texts there emerges a view of Islam which makes it dear that the writers very much consider themselves to be doing theology in dialogue. The article discusses the earliest Christian apology in Arabic; two works of Theodore Abu Qurrah; an early Summa Theologiae Arabica; and an essay in apologetics, provocatively entitled Kitab al‐burhan.  相似文献   
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957.
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   
958.
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   
959.
The equivalence of visual and auditory graphical displays was examined in two experiments. In Experiment 1, multidimensional scaling techniques were applied to paired comparison similarity judgments of both auditory and visual displays of simple periodic wave forms. In Experiment 2, a subset of perceptually similar pairs of wave forms was selected as the stimulus set for an AB-X discrimination task in both auditory and visual modalities. Results suggest much greater apparent visual-auditory equivalence for the similarity rating task than for the more difficult discrimination task, implying that one should consider the demands of the task when deciding whether auditory graphic displays are suitable alternatives to more traditional visual displays.  相似文献   
960.
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