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11.
The creation of embryos for research use has drawn a great deal of criticism. It is difficult to defend an ethical distinction between what one can do to "spare" embryos and what one can do to "research" embryos. The strongest ground on which to argue against the creation of embryos for research is a symbolic one, having to do with respect for human life. Ronald Dworkin's work in Life's Dominion on the symbolic meaning of the abortion debate throws a helpful light on this dispute. By understanding the basic question to be, Does the creation of research embryos weaken or insult our communal respect for the sanctity of human life in some way that in vitro fertilization (IVF) or the experimental use of "spare" embryos does not?, the debate can move in a more constructive direction.  相似文献   
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This article attempts to distinguish between science and technology, on the one hand, and engineering, on the other, offering a brief introduction to engineering values and engineering ethics. The method is (roughly) a philosophical examination of history. Engineering turns out to be a relatively recent enterprise, barely three hundred years old, to have distinctive commitments both technical and moral, and to have changed a good deal both technically and morally during that period. What motivates the paper is the belief that a too-easy equation of engineering with technology tends to obscure the special contribution of engineers to technology and to their own professional standards and so, to obscure as well both the origin and content of engineering ethics.  相似文献   
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In Experiment 1 four groups of rats received 30 light-shock pairings using footshock intensities of either .2, .4, .8, or 1.6 mA. One day later all rats were tested for startle by presenting tones in the presence or absence of the light CS. Potentiated startle (the difference between startle on light-tone vs tone-alone trials) was nonmonotonically related to the shock intensity used in training, with the greatest potentiation at intermediate shock levels. Experiment 3 demonstrated a similar relationship when backshocks instead of footshocks were used. In Experiment 2 rats were trained with either a moderate or high shock and then given an extended extinction-test session 1 day later. The moderate-shock group showed a gradual decline in potentiated startle over extinction. The high-shock group showed a nonmonotonic extinction curve where potentiation progressively increased toward the middle of extinction and dissipated thereafter. The results suggest that acoustic startle bears an inverted U-shaped relationship to fear and are discussed in relation to other studies concerned with this issue.  相似文献   
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An efficient method of holding individual fish in position for delivery of visual conditioned stimuli and electrical unconditioned stimuli, and for registration of breathing movements with a thermistor, is described. The holder restrains the fish gently and is readily opened and closed. In addition, a “mechanical fish” signal generator, for assessing thermistor performance in detecting breathing movements, and a safe constant-current electrical shock stimulus generator are described.  相似文献   
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Father-child relationships from the preschool years through mid-adolescence   总被引:1,自引:0,他引:1  
In this study, we examined variations in fathering and father-child relationships from the children's preschool years through mid-adolescence. One hundred seventy-seven fathers with first-born children ages 4, 8, 12, and 16 years responded to five sets of questionnaires tapping four domains of childrearing: practices, attitudes, parental role involvement, and role satisfaction. A multivariate analysis of variance identified significant variability among the four age groups in fathers' use of acceptance in childrearing practices, role involvement (frequency and task sharing), satisfaction with paternal role performance, and attitudes about the modifiability of child behavior. The results contribute new information about the nature of fathering throughout the childhood years and adolescence and provide additional support for the view of parenting as dynamic and responsive to the developmental level and gender-related characteristics of the child.  相似文献   
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A pair of experiments were conducted using a simulated courtroom trial of a criminal case. In Experiment I subject-jurors were asked by defense counsel either to imagine themselves as the defendant (empathy-inducing appeal) or to pay close attention to evidence (nonempathy appeal). Later the judge delivered only general instructions or, in addition, charged jurors to give consideration only to the facts presented. When there was no Fact-focused judge's charge, juror-subjects who heard the empathy-inducing appeal rated the defendant's actions as more lawful and attributed less of the cause for the incident to his personality than did their counterparts in the nonempathy condition. Experiment II included individual differences in the tendency to empathize as an additional mediating variable. The original pattern of effects found for the manipulated variables in Experiment I appeared again, but were overshadowed by the stronger effects of the individual difference variable and of subject sex. Subject-jurors who scored high on the empathy individual difference measure rated the defendant less guilty, assigned less cause to him, and showed corresponding mood shifts when they heard the empathy-inducing appeal. In addition, male subjects empathized more strongly with the male defendant and viewed him more favorably.  相似文献   
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This study investigated the differential effect of delayed auditory feedback (DAF) upon general (e.g., repetitions) and specific (e.g., repetitions of initial, medial, and final syllables) overt types of dysfluent behaviors. Ten moderate to severe stutterers performed an oral reading task under both NDAF and DAF (200 msec). DAF resulted in a significant increase in the total number of dysfluencies but had a differential effect upon certain general and specific behaviors. Blocks decreased significantly, prolongations increased significantly, and repetitions and interjections did not change significantly in frequency of occurence. To a limited extent, DAF had a differential effect on specific behaviors. All specific prolongation behaviors increased significantly while only one specific block behavior (ddelays in starting words) decreased. The authors discuss these results in terms of the vocal changes that occurred under DAF and speculate as to their importance in establishing fluency. DAF is viewed as promoting prolongations and prolongations are viewed as inhibiting excessive stoppages of the breathstream, thus promoting fluency (e.g., delays in starting words).  相似文献   
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