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171.
Recently, debate about the distribution of scarce organs for transplantation has focused on whether patients should have the right to place themselves on waiting lists at several transplant centers, thereby gaining an advantage over other potential recipients. This article explores the social and ethical issues raised by multiple listing, contrasting policies adopted at the national level with those implemented in New York State. It concludes by examining the implications of the debate for broader questions about entitlement and access to health care.  相似文献   
172.
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   
173.
We assessed the effects of a computerized matching-to-sample procedure on the spelling performances of three students with mental retardation. Initially, the students could 1) match pictures and printed words to one another, and 2) match pictures and printed words to spoken words. However, they could not construct words to either pictures or spoken words (e.g., touch, in order, the letters s->h->o->e given the spoken-word sample Shoe). Word constructions then improved markedly after exposure to delayed constructed-response identity matching (e.g., touch the letters s->h->o->e given the printed-word sample shoe). One subject's oral and written spelling also improved. The results extend previous research by showing multiple positive effects of a computerized spelling intervention. These effects may have occurred in part because of the formation of stimulus classes among pictures, printed words, and spoken words.  相似文献   
174.
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   
175.
The American eugenics movement had a significant impact on American social history, and analysis of the movement illustrates the relationship among science, scientists, and society. The history of the American eugenics movement as well as more recent examples of eugenic thought and biological determinism are reviewed. The need for genetic counselors to confront eugenic issues in their own profession and in society is discussed.  相似文献   
176.
The purpose of this research was to examine the relationship between parents' perceptions of marital satisfaction and family stress and their third grade children's classroom behavior. Twenty-one married couples completed questionnaires during home visits. Behavior observations were made from videotapes of children recorded in their classroom during lunch and group academic periods on each of three days. Frequencies of peer interactions, solitary behaviors, and teacher interactions were coded. Regression analyses showed that mothers' level of marital satisfaction (but not fathers') predicted their children's frequency of peer interactions during lunch. Fathers' level of perceived family stress (but not mothers') predicted their children's frequency of peer interactions during lunch. Neither measure for either parent was related to the frequency of peer interactions, solitary behaviors, or teacher interactions observed during the academic sessions. These findings highlight the importance of assessing the potential differential relation of parent variables to children's trans-situational behaviors, and the examination of these variables in relation to different social-environmental contexts in which children participate outside the home.  相似文献   
177.
This brief report proposes an extension of the traditional Alternating Treatments Design that would be acceptable to use in hospital and residential settings where subjects are often not concurrently available. Concerns about the inability of traditional designs to work in these special situations and the emergence of a “scientist–practitioner split” are discussed. An example of how the Extended Alternating Treatments Design might be used is provided.  相似文献   
178.
Pigeons’ pecking has long been a subject of interest in behavioral research, with the response typically being viewed as unitary. Recent experiments done with computer-controlled devices have revealed that this response is at least bipartite in character, with beak opening and response location (head transport) as its components. In addition, experimental work has demonstrated that these response components may be separately influenced and controlled by respondent and operant conditioning procedures. The detailed topographic analysis and technology that have emerged may provide a background for similar work with other behavioral systems.  相似文献   
179.
The costs produced by invalid precues can depend on the spatial relationship between the cued location and the target location. If oculomotor programs mediate attention shifts, then the effect of varying the spatial relation between the cue and target should be the same for covert orienting (indexed by manual responses) and saccadic responses. We found this to be true only for central precues. With central precues, both manual and saccadic costs were greater when cue and target occurred on opposite sides of the vertical meridian than when they occurred on the same side. With peripheral precues, there were no meridian effects in either response condition, but there was a significant dissociation in the pattern of saccadic and manual costs. For manual responses costs were greater when the target was eccentric relative to the cue, whereas for saccades costs were greater when the cue was eccentric to the target. These results provide additional support for the idea that different orienting mechanisms are engaged by central and peripheral precues. They further suggest that the relationship between oculomotor and attentional orienting may depend on the nature of the precue, with the potential for interdependence being greater with central precues.  相似文献   
180.
Head-related transfer functions for differently centered narrow noise bands were obtained on 6 subjects. Derived from these measurements were covert peak areas (CPAs), defined as the spatial constellation of loudspeakers that generates maximal sound pressure at the entrance of the ear canal for specific bands of frequency. On the basis of previous data, we proposed that different frequency bands served as important spectral cues for monaural localization of sounds from different loci and that location judgments were directed toward the CPAs associated with the different bands. In the first study, the stimuli were bandpass filtered so that they contained only those frequencies whose associated CPAs occupied either the monaural listener’s “upper” or “lower” spatial regions. Loudspeakers, separated by 15°, were stationed in the left hemifield, ranging from 0° to 180° azimuth and ?45° to 60° elevation. Subjects reported the loudspeaker from which the sound appeared to originate. Judgments of the sound’s elevation were in general accord with the CPAs associated with the different frequency segments. In the second study, monaural localization tests were administered in which different 2.0-kHz-wide frequency bands linked with specific CPAs were notch filtered from a 3.5-kHz highpass noise band. For the control condition, the highpass noise was unfiltered. The data demonstrated that filtering a frequency segment linked with specific CPAs resulted in significantly fewer location responses directed toward that particular spatial region. These results demonstrate in greater detail the relation between the directional filtering properties of the pinna and monaural localization of sound.  相似文献   
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