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131.
132.
James Lindemann Nelson 《Theoretical medicine and bioethics》1992,13(4):319-328
Mary Anne Warren's claim that there is room for only one person with full and equal rights inside a single human skin ([1], p. 63) calls attention to the vast range of moral conflict engendered by assigning full basic moral rights to fetuses. Thereby, it serves as a goad to thinking about conflicts between pregnant women and their fetuses in a way that emphasizes relationships rather than rights. I sketch out what a care orientation might suggest about resolving gestational conflicts. I also argue that the care orientation, with its commitment to the significance of the partial and the particular, cannot be absorbed within standard, impartialist moral theory. 相似文献
133.
A structural analysis of the problem behaviors of 32 adults with mental retardation living together in a residential facility showed that a disproportionate number of these behaviors were associated with a period of time scheduled for leisure activities. A staff management program was implemented during this time which included activity and staff scheduling, staff inservice training, and staff performance monitoring and feedback. The results showed an 83% decrease in problem behaviors when the program was implemented during the leisure period and no decrease in problem behaviors during adjacent time periods where the program was not utilized. Follow-up assessments indicated maintenance of these decreased levels of behavior at 3 and 6 months. It was concluded that this approach of combining a structural analysis with staff management procedures was effective in reducing a high level of problem behavior in a residential setting. The results are discussed with regard to pragmatic strategies for the pretreatment analysis of problem behaviors in residential settings, and the role of organizational behavior management techniques in habilitative programing for individuals with behavior disorders. 相似文献
134.
135.
136.
Daniel D. Houlihan Robert N. Jones Howard N. Sloane Joni Cook 《Behavioral Interventions》1992,7(1):71-77
This brief report proposes an extension of the traditional Alternating Treatments Design that would be acceptable to use in hospital and residential settings where subjects are often not concurrently available. Concerns about the inability of traditional designs to work in these special situations and the emergence of a “scientist–practitioner split” are discussed. An example of how the Extended Alternating Treatments Design might be used is provided. 相似文献
137.
Adrienne Y. Lee 《Behavior research methods》1992,24(2):205-212
HyperCard was used to develop a simplified tutoring system whose principles were based on a learning theory, and a genetics tutoring system was evaluated experimentally. Learning was studied by examining immediate versus delayed feedback after an error was made. Such tutoring systems aid in psychological studies of learning, because experimental variables can be easily manipulated. HyperCard provides a good vehicle for tutoring system development, since it requires no extensive programming skills. 相似文献
138.
James E. Skinner Mark Molnar Tomas Vybiral Mirna Mitra 《Integrative psychological & behavioral science》1992,27(1):39-53
The application of “chaos theory” to the physical and chemical sciences has resolved some long-standing problems, such as how to calculate a turbulent event in fluid dynamics or how to quantify the pathway of a molecule during Brownian motion. Biology and medicine also have unresolved problems, such as how to predict the occurrence of lethal arrhythmias or epileptic seizures. The quantification of a chaotic system, such as the nervous system, can occur by calculating the correlation dimension (D2) of a sample of the data that the system generates. For biological systems, the point correlation dimension (PD2) has an advantage in that it does not presume stationarity of the data, as the D2 algorithm must, and thus can track the transient non-stationarities that occur when the systems changes state. Such non-stationarities arise during normal functioning (e.g., during an event-related potential) or in pathology (e.g., in epilepsy or cardiac arrhythmogenesis). When stochastic analyses, such as the standard deviation or power spectrum, are performed on the same data they often have a reduced sensitivity and specifity compared to the dimensional measures. For example, a reduced standard deviation of heartbeat intervals can predict increased mortality in a group of cardiac subjects, each of which has a reduced standard deviation, but it cannot specify which individuals will or will not manifest lethal arrhythmogenesis; in contrast, the PD2 of the very same data can specify which patients will manifest sudden death. The explanation for the greater sensitivity and specificity of the dimensional measures is that they aredeterministic, and thus are moreaccurate in quantifying the time-series. This accuracy appears to be significant in detecting pathology in biological systems, and thus the use of deterministic measures may lead to breakthroughs in the diagnosis and treatment of some medical disorders. 相似文献
139.
Quantification of a chaotic system can be made by calculating the correlation dimension (D2) of the data that the system generates
(Packard et al., 1980). The D2 algorithm, however, requires stationarity of the generator, a feature that biological data
rarely reflect (Mayer-Kress et al., 1988). So we developed the “point correlation dimension” (PD2), an algorithm that accurately
tracks D2 in linked data of different dimensions (Carpeggiani et al., 1991). We now present a mathematical argument that,
for stationary data, individual PD2s converge to D2 and we demonstrate that the algorithm rejects contributions made by bursts
of noise. Data were obtained from the surface of the olfactory bulb of the conscious rabbit (64 electrodes, 640 Hz each, 1.3
sec epochs) before and after presentation of a novel or habituated odor. D2 could be calculated in only 1 of 10 novel-odor
trials, whereas PD2 could be calculated in all. Both algorithms indicated that a novel odor evokes a spatially uniform dimensional
increase. The PD2 uniquely exhibited the dimensional decreases that occur during inspiration and the gradients of mean dimension
present during the nonstimulated control state. These control gradients remained unchanged without odor experience, but showed
spatially specific PD2 increases following odor habituation. It is interpreted that, 1) the PD2 issensitive, accurate, and appropriate for dimensional assessment of biological data, 2) that during analysis of unfamiliar information a singleglobal process is transiently evoked in the neuropil, and 3) after experience multiplespatially specific processes tonically map the sites of learning.
Grant Support: National Institutes of Health, HL 31164 and NS27745 相似文献
140.
James A. Bashford Keri R. Riener Richard M. Warren 《Attention, perception & psychophysics》1992,51(3):211-217
Outside of the laboratory, listening conditions are often less than ideal, and when attending to sounds from a particular source, portions are often obliterated by extraneous noises. However, listeners possess rather elegant reconstructive mechanisms. Restoration can be complete, so that missing segments are indistinguishable from those actually present and the listener is unaware that the signal is fragmented. This phenomenon, called temporal induction (TI), has been studied extensively with nonverbal signals and to a lesser extent with speech. Earlier studies have demonstrated that TI can produce illusory continuity spanning gaps of a few hundred milliseconds when portions of a signal are replaced by a louder sound capable of masking the signal were it actually present. The present study employed various types of speech signals with periodic gaps and measured the effects upon intelligibility produced by filling these gaps with noises. Enhancement of intelligibility through multiple phonemic restoration occurred when the acoustic requirements for TI were met and when sufficient contextual information was available in the remaining speech fragments. It appears that phonemic restoration is a specialized form of TI that uses linguistic skills for the reconstruction of obliterated speech. 相似文献