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41.
A semiautomatic version of the Wisconsin General Test Apparatus is described along with circuitry. Comparison data are provided for the semiautomatic and manual WGTA obtained under comparable procedures and conditions. Response latencies are given for go/no-go object discrimination problems and subsequent retention tests.  相似文献   
42.
A swivel was developed for concurrent intraorganismic fluid injection and intracranial electrical stimulation of the unrestrained rat. Effects of various intragastric injections on bar-pressing maintained by electrical stimulation of the hypothalamus were studied. In some subjects, intragastric injections of either water or milk decreased the rate of responding. This decrease resulted from pauses in responding rather than from decreases in the local rates of responding. The decrement in responding occurred at a lower gastric volume during milk injection than during water injection. In other subjects, however, neither water, milk, nor 32% sucrose injections affected the rate of self-stimulation.  相似文献   
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Cortical steady-potential shifts obtained from nonpolarizing electrodes chronically implanted in freely moving cats and rats reveal cortical activation related to urgency of response to unconditional and conditional stimuli. Such shifts appear relatively independent of activation in the rhythmic electrocorticogram and are related to higher levels of activation. Shifting is found to be modulated by drive and level of learning, suggesting a correlation with the proposed reaction potential of Hull. Both approach and avoidance “urgency” are reflected in the onset slope and amplitude of SP shifts in a manner suggesting modulation of cortical activation by the effects of behavioral regulation of stimulus conditions.  相似文献   
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The effects of varying CO2 concentration, and intervals between CO2 presentations, were determined from the performance by five pigeons of a learned motor act which eliminates CO2 from the inspired air. The length of time from the onset of an externally-produced increase in inspired CO2 to the performance of the learned motor response terminating the CO2 presentation was inversely related to the CO2 concentration presented (3 per cent and 5 per cent) and directly related to the inter-trial interval (3 minutes and 1.5 minutes). Chemoreceptors on the ventrolateral surfaces of the medulla are postulated to be the initial site of stimulation in the chain of events leading to the behavioral bioregulation of inspired CO2 concentration.  相似文献   
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The dead donor rule--that persons must be dead before their organs are taken--is a central part of the moral framework underlying organ procurement. Efforts to increase the pool of transplantable organs have been forced either to redefine death (e.g., anencephaly) or take advantage of ambiguities in the current definition of death (e.g., the Pittsburgh protocol). Society's growing acceptance of circumstances in which health care professionals can hasten a patient's death also may weaken the symbolic importance of the dead donor rule. We consider the implications of these efforts to continually revise the line between life and death and ask whether it would be preferable to abandon the dead donor rule and rely entirely on informed consent as a safeguard against abuse.  相似文献   
48.
The traditional family composition model of children's divorce adjustment was compared to a family competence model. Subjects included 81 children whose parents remained married, were divorced, or were divorced and subsequently remarried. Divorced families had been separated for between 24 and 48 months. Custodial parents completed questionnaires regarding family functioning, occurrence of stressful life events, and child's psychosocial adjustment. Children completed questionnaires regarding parenting behaviors and self-esteem. A trained examiner conducted a structured diagnostic interview of the child. Multivariate analysis of covariance showed that family composition had a significant effect on the occurrence of stressful events and change in income but not children's adjustment. Hierarchical multiple regression correlations indicated the most powerful predictors of child adjustment were family competence variables which accounted for 21% of the variance in child adjustment scores. In contrast, family composition accounted for only 8% of variance in child adjustment scores. Further, hierarchical multiple regression correlations indicated that higher levels of family functioning were associated with families where parental hostility was low and parents displayed few rejecting behaviors while practicing consistent and appropriate discipline.  相似文献   
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The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
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