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881.
882.
The World-Wide Web provides an inviting opportunity to reach large numbers of people, both as an audience for psychoacoustical discussions and demonstrations and as subjects for psychoacoustical experiments. Such use of the Web poses a unique set of challenges. We present the methodologies used to prepare a multimedia primer in auditory perception at McGill University. As well as instructional material, this primer includes acoustical experiments conducted over the Web. We discuss the response and experiences with this site in general and in a particular class situation at Hanover College.  相似文献   
883.
Congenital bilateral absence of the vas deferens (CBAVD) occurs in approximately 1.3% of infertile males and is thought to be, in most cases, a primarily genital form of cystic fibrosis (CF). Fourteen males with CBAVD considering microsurgical sperm aspiration from the epididymis (MESA) and in vitro fertilization were seen for genetic counseling and screening for CF. To retrospectively evaluate these patients' perceptions of the counseling and screening information, we conducted structured telephone interviews to assess their recall of information about CF and its impact on their health concerns and reproductive plans. We found that, as the health implications of CF are abstract and not as important to patients as the diagnosis of CBAVD itself, patients tend to view their CF status primarily in terms of their reproductive potential. Retrospective analysis afforded us an opportunity to identify the psychosocial issues of most concern to this unique patient population.  相似文献   
884.
This article reports of the activities of the working group, Ethics & Engineers, of the Royal Flemish Society of Engineers. More particularly, the ethical problems that engineers face in the preparation of an environmental report are illuminated. Irrespective to which party the engineer belongs, he or she is confronted with the difficult weighting of his or her personal interest, the interests of private companies and last but not least the common good. It is argued that the implementation of a code of ethics and the introduction of courses on engineering ethics into the education of engineers would strengthen the engineer in the fulfilment of his vocation. Dirk Holemans is a bio-engineer preparing a doctoral thesis on the social responsibility of engineers, Herman Lodewyckx teaches ethics and has research interests in professional and applied ethics.  相似文献   
885.
We explore a model that examines how personal and environmental variables explain violent behavior by adolescents. Repeated interviews with youths from 1984–1992 from 10 cities across the United States provided the data. These interviews first occurred with 2,787 youths when they were adolescents (1984–85 and 1986–87) and the interviews were repeated on a subsample of 602 youths when they were young adults (1989–90 and 1991–92). Longitudinal multivariate analyses showed that almost a third of the variance in adolescent violent behaviors was predicted by a combination of personal variables (gender, substance misuse) and environmental variables (history of child abuse, stressful events, traumatic events, and city rates of unemployment). Further, almost a third of the variance in change in violent behaviors from year to year was predicted by prior violent behavior and a combination of personal variables (gender, suicidality, and substance misuse) and environmental variables (stressful events).  相似文献   
886.
Exposure to numerical examples (seed facts) produced a substantial long-term reduction in domain-specific innumeracy. In particular, learning the populations of 24 seed countries improved accuracy of estimates of the populations of 75 untrained countries, both at the time of learning and 4 months later. Consistent with abstraction-based theories of learning and memory, the benefits of having been exposed to the seed facts were as large 4 months after the exposure as immediately after it, despite the specific populations of the seed countries having been forgotten during the interval.  相似文献   
887.
We tested the notion that better foster care adjustment would be observed when the temperaments of mothers and fathers were matched with those of adolescent foster children. We hypothesized that families in which foster parents and foster children had high (easy) scores on subscales of the Revised Dimensions of Temperament Scale (DOTS-R) would also report higher family functioning and higher foster care adjustment than parents and children from families in which one or both family members had low (difficult) scores on these scales. The hypotheses were supported when the mothers and fathers family assessments were used but rejected when the observations of the case managers and adolescents were tested. Methodological and substantive explanations for the findings are discussed and recommendation for foster care practice and continuing research are provided.  相似文献   
888.
This study investigated the prevalence of traumatic brain injury (TBI) in an inpatient psychiatric population. We hypothesized increased prevalence of TBI relative to the general population due to a variety of risk factors observed in psychiatric patients. One hundred (mean age = 34) psychiatric inpatients completed the revised Head Injury Questionnaire. Chart review of 17 subjects reporting injuries established whether injuries were documented in medical records. Sixty-eight percent of this psychiatric population reported one or more injuries in which they were unconscious or dazed. This number is higher than the prevalence in the general population. Injuries were generally of mild to moderate severity; multiple injuries were common. Chart review of 17 subjects reporting TBI indicated that histories of TBI had not been noted in the medical record. Finally, 63% of TBI subjects reported that their injury predated the onset of their psychiatric symptoms. These results suggest a possible role of TBI in psychiatric symptomatology and have implications for psychiatric treatment in this population.  相似文献   
889.
This paper makes the assumption that organ transplantation is, under some conditions at least, a proper use of communal medical resources. Proceeding from this assumption, the author: (1) sketches the history of the problem; (2) briefly examines the prevalent models of communal structure and offers an alternate version; (3) discusses notions of justice and obligation derived from these different models; (4) applies these to the practice of harvesting organs for transplantation; and then (5) offers a different process for harvesting organs from the newly dead. If community is viewed as united by a set of shred goals and common values among which the value of community itself is important, then certain reciprocal obligations among members obtain. I suggest that routine salvage of organs from the newly dead be instituted but that it be routine salvage “with a twist”: rather early in life all members of the community are given the opportunity to refuse but their refusal carries the reciprocal condition that they cannot later become the recipients of that which they refuse to others.  相似文献   
890.
An aftereffect of perceived texture density contingent on the color of a surrounding region is reported. In a series of experiments, participants were adapted, with fixation, to stimuli in which the relative density of two achromatic texture regions was perfectly correlated with the color presented in a surrounding region. Following adaptation, the perceived relative density of the two regions was contingent on the color of the surrounding region or of the texture elements themselves. For example, if high density on the left was correlated with a blue surround during adaptation (and high density on the right with a yellow surround), then in order for the left and right textures to appear equal in the assessment phase, denser texture was required on the left in the presence of a blue surround (and denser texture on the right in the context of a yellow surround). Contingent aftereffects were found (1) with black-and-white scatter-dot textures, (2) with luminance-balanced textures, and (3) when the texture elements, rather than the surrounds, were colored during assessment. Effect size was decreased when the elements themselves were colored, but also when spatial subportions of the surround were used for the presentation of color. The effect may be mediated by retinal color spreading (Pöppel, 1986) and appears consistent with a local associative account of contingent aftereffects, such as Barlow’s (1990) model of modifiable inhibition.  相似文献   
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