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The question of the morality ofin vitro fertilization is examined. One of the central questions to be answered is whether the zygote loss that seems inseparable from the process is morally justified. Even when embryo transfer occurs, many zygotes which have been intentionally created are intentionally destroyed; they are used as means to the alleged benefits that others will attain (the benefit to the infertile couple, to the child produced by the process, and to those who might benefit from the increase of genetic knowledge that allegedly will occur fromin vitro research). The justifications advanced in defense of early abortion are discussed, and it is shown that these justifications must be totally distinct from those advanced in support ofin vitro fertilization. A theory of values is proposed which shows why a set of reasons may justify early abortion, but not an abortion late in the pregnancy. This theory states that the value characteristics of an entity are notidentical to the characteristics which make the entityhuman. It is concluded that if certain key empirical assumptions are correct, then in vitro fertilization is a morally permissible process; however, the falsity of these assumptions, or the unsoundness of the theory of value, might well result in a reversal of this judgment.  相似文献   
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The relationship between job satisfaction and life satisfaction is examined, using regression analyses which control the effects of satisfaction with domains other than the job and conditions associated with the workplace and with life away from work. Results from data analyses of two independent sets of survey data are used to elaborate and refine a multivariate framework for relating overall life satisfaction and job satisfaction.  相似文献   
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Although substantial research has been conducted on chronic fatigue syndrome (CFS) over the past decade, the syndrome remains poorly understood. The most recent case definition describes CFS as being characterized both by disabling fatigue and by subjective reports of difficulty with concentration and short-term memory. However, research into the neurocognitive and psychological functioning of individuals with CFS has provided mixed objective results. The current paper reviews studies that have examined the neurocognitive and/or psychological functioning of individuals with CFS. Changes in research design and instruments employed to study individuals with CFS are suggested.  相似文献   
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We examined methods for determining how extinction should be applied to different functions of self-injurious behavior (SIB). Assessment data indicated that the head banging of 3 children with developmental disabilities was maintained by different reinforcement contingencies: One subject's SIB was positively reinforced by attention from adults, the 2nd subject's SIB was negatively reinforced by escape from educational tasks, and the 3rd subject's SIB appeared to be automatically reinforced or “self-stimulatory” in nature. Three functional variations of extinction—EXT (attention), EXT (escape), and EXT (sensory)—were evaluated, and each subject was exposed to at least two of these variations in reversal or multiple baseline designs. Reductions in SIB were observed only when implementation of “extinction” involved the discontinuation of reinforcement previously shown to be responsible for maintaining the behavior. These results highlight important differences among treatment techniques based on the same behavioral principle (extinction) when applied to topographically similar but functionally dissimilar responses, and further illustrate the practical implications of a functional analysis of behavior disorders for designing, selecting, and classifying therapeutic interventions.  相似文献   
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