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951.
952.
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 is sensitive, accurate, and appropriate for dimensional assessment of biological data, 2) that during analysis of unfamiliar information a single global process is transiently evoked in the neuropil, and 3) after experience multiple spatially specific processes tonically map the sites of learning. 相似文献
953.
J S Howard 《Integrative Physiological and Behavioral Science》1992,27(3):209-215
Past literature suggests a link between certain psychotic states and adrenal androgen production, including Dehydroepiandrosterone (DHEA). A group of severely psychotic androgenized females, refractory to substantial amounts of neuroleptics, has been identified for whom endocrine testing revealed abnormally high levels of DHEA. A similar group has been identified among the severely psychotic male population. Improvement in psychosis appears to occur as DHEA returns to its normal range using standard low dose Dexamethasone suppression. 相似文献
954.
955.
956.
This study of 20 ‘white-collar’ workers aged 20–30 measured motivation, enjoyment and access to various categories of experience in both work and leisure, and examined their relationship with psychological well-being on a number of dimensions. The method used a short questionnaire, psychological scales and the innovatory ‘experience sampling methodology’ (ESM) where respondents answer questions in a diary on the receipt of a signal from a pre-programmed watch or radio pager eight times a day for 1 week. The results show, in line with other studies, that intrinsic motivation in daily life is correlated with happiness but that, not previously reported, when motivation at work is examined both extrinsic motivation and instances where a person had to do the activity but did not wish to be doing something else, i.e. ‘positive motivational change’, are correlated with positive aspects of psychological well-being, while instances where a person wanted to do the activity but wished to be doing something else, i.e. ‘negative motivational change’, correlated with negative aspects. The results also show that enjoyment in both work and leisure correlates with aspects of psychological wellbeing; and that macro ‘flow’ experiences, where high skills and high challenges are perceived as equal, are enjoyable and interesting and come primarily from work. The study also shows that categories of experience considered important for psychological well-being and deemed to come primarily from work can be obtained in leisure. The results are discussed in the context of person—situation interactions and processes, and it is advocated that these should be studied in a variety of samples. 相似文献
957.
The field of applied behavior analysis has devoted considerable effort to the problem of educating America's youth. In addition to developing a wide range of procedures to improve children's academic and classroom survival skills, behavioral researchers have discussed a wide range of technological characteristics that are likely to facilitate the adoption of their procedures by educational decision-makers and practitioners. A movement to restructure American schools has become highly popularized within educational, political, and public media forums over the past several years. One general characteristic of this movement is its failure to recommend the more frequent implementation of applied behavior analysis techniques to educate America's youth. A close inspection of three global models for school reform, however, reveals notable compatibilities with the focus and goals of applied behavior analysis. Applied behavior analysts can collaborate with and contribute to the school restructuring movement by pursuing the more formal and systematic analyses of characteristics essential to the adoption process. 相似文献
958.
Trickett EJ 《Ethics & behavior》1992,2(2):91-100
Research and intervention involving primary prevention [related to mental health and psychology] have grown dramatically in the past 10 years. However, little attention has been paid to ethical issues in primary prevention. This article proposes a framework for increasing awareness of such issues. The framework centers on explicating the contexts where prevention activities occur and the roles adopted by interventionists engaging in these activities. Several assumptions underlying primary prevention are stated, and ways of clarifying ethical issues are proposed. 相似文献
959.
Three commentaries are offered on the following case: George, age 57, is a previously healthy man who recently underwent surgery for removal of a low-grade malignant thymoma. At the time of admission to the hospital, George stressed to the staff that he had long ago signed a "living will," which he renewed immediately after he learned of his cancer diagnosis. At the time of surgery, the tumor was found to extend into his mediastinum; although it was removable, this required revision of part of the sternum and grafting of the vessels feeding the heart chambers. Because of the resultant tissue damage and neuronal hyperactivity, George experienced postoperative episodes of cardiac arrhythmia and bronchospasm. Unanimous medical opinion was that this situation was a temporary problem that would resolve itself as the tissues healed. Until that time, however, it will be difficult to wean him from ventilatory support. When his stay in the intensive care unit became prolonged, George and his family began to insist that his status be changed to "do not resuscitate" and reminded the staff about his longstanding living will. All of this is happening despite the fact that the patient and family seemingly comprehend that although the short-term interventions are invasive, there is a high probability of a successful outcome. George's cancer prognosis is excellent, and, although he may well have an episode of life-threatening arrhythmia, he is likely to respond to resuscitation interventions. Once the immediate postoperative period is over, his potential for a long and productive life with full capacities is excellent. Consider the following questions: (a) Should George's expressed wishes be respected, or should the staff take additional steps to help him survive the postoperative period, even if that means violating his stated wishes? and (b) What steps might the staff follow in sorting through this problem? 相似文献
960.
David J. Doukas 《Theoretical medicine and bioethics》1992,13(1):5-14
The emergence of the ethics consultation as a means to resolve moral crises in clinical medicine has revealed the need for a worksheet that would facilitate intake and analysis. The author developed the Bioethics Consultation Form as an attempt to remedy this need. The form is arranged in an outline format and is a useful asset to ethics committee discussions and record keeping. The first section covers basic intake data concerning the patient's medical and personal information, advance directives, and values, as well as the values of the physician and family. After the intake section is completed with the above data, the ethics consultant then turns to the analysis section. This second section allows for (1) the discussion of conflicting values, (2) the identification of priorities, and (3) the elucidation of ethical norms relevant to the case.The Bioethics Consultation Form was adopted by the Patient Care Advisory committee of the Franklin Square Hospital Center in Baltimore, Maryland in 1986. The methodology in the use of the form will be discussed. Further, the potential spectrum of consultative cases that can be analyzed using the form will be highlighted. 相似文献