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951.
Some properties are discussed of regular polygons that may result from angular homeostatic processes in stable orbit. To characterize these homeostatic polygons we need to discuss the winding number, the sidedness (integer, fractional and irrational), multiplicity, envelopes, and density. A regular (i.e., equilateral, equiangular) polygon may be closed in one revolution about its unique center, in multiple revolutions, or not at all. A homeostatic polygon can be generated only if all vertices are included in a single polygon, which occurs if and only if the number of vertices and the number of revolutions required to complete the polygon are relatively prime. For the homeostatic polygon to have a finite number of sides (without repeating itself) the angle subtended by any two successive vertices at the center must be a rational multiple of 2. Biological implications of these properties are illustrated.  相似文献   
952.
The challenge of excellence in community health services has been taken up by medical educators in Colombia. Confronted with a nation where the primary indicators of disease mortality and morbidity (cardiovascular disease and infant mortality) were characteristic of First and Third World patterns, respectively, the Ministry of Health and La Asociacion Colombiana de Facultades de Medicina (ASCOFAME), representatives of institutions of medical education, have collaborated to conduct a needs assessment of the country's health needs and devised an implementation plan designed to better address the needs of the majority of that nation's people.As a model, the Colombian reorganization of medical education is an example which could be emulated by the U.S. where policy makers are struggling with troublesome questions of cost, equity and quality.  相似文献   
953.
In a previous essay I criticized Engelhardt's libertarian conception of justice, which grounds the view that society's obligation to assure access to adequate health care for all is a matter of beneficence [1]. Beneficence fails to capture the moral stringency associated with many claims for access to health care. In the present paper I argue that these claims are really matters of justice proper, where justice is conceived along moderate egalitarian lines, such as those suggested by Rawls and Daniels, rather than strong egalitarian lines. Further, given the empirical complexity associated with the distribution of contemporary health care, I argue that what we really need to address the relevant policy issues adequately is a theory of health care justice, as opposed to an all-purpose conception of justice. Daniels has made an important start toward that goal, though there are some large policy areas which I discuss that his account of health care justice does not really speak to. Finally, practical matters of health care justice really need to be addressed in a ‘non-ideal’ mode, a framework in which philosophers have done little.  相似文献   
954.
In this paper, digital filters are described for concurrent adaptive estimation of the spectral powers at several target frequencies. Least-squares estimation is used, with a tapered weight function that discounts time-series data according to age. Frequency selectivity and reliability of spectral estimates are controlled by different parameters. The spectral windows are closely approximated by Student’st distribution, which is useful in the planning of experiments.  相似文献   
955.
The sentence verification technique (SVT), developed by Royer, Hastings, and Hook (1979), provides developmental and educational researchers with an alternative way of assessing text comprehension based on all of the information contained in a passage. Students must decide if test sentences have the same meaning as sentences that appeared in an original passage. The program described here automates the more laborious aspects of constructing SVT tests. The user must create a passage using a word processor. The program will prompt the user for information as needed. Finally, printable text files (SVT test and answer key) are generated. The program is written in BASIC for IBM and IBM-compatible computers.  相似文献   
956.
957.
In this study, the authors analyzed demographic data on 403 Oklahoma inmates who went through the Regimented Inmate Discipline Program in 1984–1985. Also, a sample of the inmates was interviewed to identify the most supportive components of the program.  相似文献   
958.
Traumatic brain injury can result in behavioral and physical deficits that require intensive post-acute residential rehabilitation. Behaviors targeted by such programs include basic self-care and living skills. We examined the efficacy of a behavioral training strategy to teach appropriate medical treatment of four different groups of simulated cold symptoms to an anoxic brain injured adult. The strategy included instructor prompting and feedback in the use of written task analyses and picture cues as self-administered prompts. Subsequent to baseline, the participant used written generic task analyses combined with picture cues and then, if necessary, written specific task analyses combined with picture cues to prompt appropriate self-treatment of the four types of colds. Written individualized task analyses, tailored to participant errors, were used to fade specific task analysis prompts and transfer stimulus control to the discriminative stimuli present in the picture cues. A multiple baseline design across responses showed that skill acquisition did not occur after generic task analysis training, but did so after specific task analysis training. The participant responded to all four types of colds for three consecutive trials at 100% correct under baseline conditions. Follow-up results indicated that transfer of stimulus control to the cold symptoms simulated by the picture cues alone did not maintain over time. Correct responding was retrained using generic and, if necessary, individualized task analysis training conditions.  相似文献   
959.
The literature reports a number of reasons why abuse of people with mental retardation occurs. These causes of abusive behavior can be divided into three categories: organizational variables, staff characteristics, and client characteristics. The author examines each of the variables and presents recommendations for reducing their contributions to abusive behavior.  相似文献   
960.
In this study, an autistic youth served as peer prompter for three other autistic adolescents. The peer prompter encouraged the other boys to talk about sports, a topic frequently discussed by typical teenagers. A multiple-baseline design across participants was used to assess the effectiveness of the peer-prompting procedure. During baseline, the youth rarely talked about sports, although all three had previously completed a sports-appreciation class and had displayed large pre-to-post gains on a paper-and-pencil test. During intervention, when a peer prompted sports discussions, all three youth engaged in much more sports-related conversation. Generalization measures indicated that: (1) the youth engaged in sports discussions in groups, as well as in the dyads that characterized the training situation; (2) they talked about sports in a setting other than the training setting; (3) they discussed sports with their peers when an unfamiliar teacher was present; and (4) they continued to discuss sports when training tapes and behavioral contracts between the teacher and the peer prompter were withdrawn. Previously, it has been common to use nonhandicapped or less-handicapped peers as tutors; this study demonstrates that an autistic youth may also effectively serve as a prompter who assists his schoolmates in acquiring conversational skills that contribute to their normalization.  相似文献   
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