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791.
In recent years there has been an increase in the number of requests formercy killings by patients and their relatives. Under certain conditions,the patient may prefer death to a life devoid of quality. In contrast to thosewho uphold this quality of life approach, those who hold the sanctity oflife approach claim that life has intrinsic value and must be preservedregardless of its quality. This essay describes these two approaches,examines their flaws, and offers a golden path between the two extremepositions.We discuss the halachic and the secular views, arguing for a balancebetween the sanctity of life and the quality of life. We argue that, indeed,such a balance exists in practice, and that life is important, but it is not sacred. Life can be evaluated, but quality of life is not the solecriterion.  相似文献   
792.
This paper attempts to update the 18th century concept of progress by an evolutionary theoretical framework, while replying to some of the contemporary critiques. Progress, understood as increase in fitness (or its proxy, quality of life) necessarily accompanies evolution by natural selection. In socio-cultural evolution, this mechanism is reinforced by growth of knowledge and virtuous cycles, but can be accompanied by negative side-effects such as overshooting and parasitism. The most pressing of the contemporary side-effects, such as pollution and the increased pace of life, are discussed, but it is concluded that they can be tackled without really endangering global progress. The anxiety that they engender is unfortunately amplified by a bad news bias in the media, leading to an inappropriately pessimistic view of the situation by the public.  相似文献   
793.
Four rats responded under a simple fixed consecutive number schedule in which eight or more consecutive responses on the run lever, followed by a single response on the reinforcement lever, produced the food reinforcer. Under this simple schedule, dose-response curves were determined for diazepam, morphine, pentobarbital, and phencyclidine. The rats were then trained to respond under a multiple fixed consecutive number schedule in which a discriminative stimulus signaled when the response requirement on the run lever had been completed in one of the two fixed consecutive number component schedules. Under control conditions, the percentage of reinforced runs under the multiple-schedule component with the discriminative stimulus added was much higher than the percentage of reinforced runs under the multiple-schedule component without the discriminative stimulus. All of the drugs decreased the percentage of reinforced runs under each of the fixed consecutive number schedules by increasing the conditional probability of short run lengths. This effect was most consistently produced by morphine. The drugs produced few differences in responding between the multiple fixed consecutive number components. Responding under the simple fixed consecutive number schedule, however, was affected at lower doses of the drugs than was responding under the same fixed consecutive number schedule when it was a component of the multiple schedule. This result may be due to the difference in schedule context or, perhaps, to the order of the experiments.  相似文献   
794.
This paper examines the symbolic nature of the psychosomatic symptom. It is suggested that the psychosomatic symptom is an informationally rich symbolic derivative of the Self that serves to focus attention on developmental disturbances in the archetypal processes of constructing body image and interpreting dysphoric somatic sensations. Clinical examples are offered to illustrate the changing nature of the psychomatic symptom in society. The therapeutic importance of monitoring affectual transactions in the transference-countertransference field is stressed.  相似文献   
795.
We replicated a program to increase indices of happiness among people with profound multiple disabilities and conducted a component analysis of the program. The program involved presentation and contingent withdrawal of stimuli that had been identified as preferred based on preference assessments and staff opinion. The program was implemented with 3 adult students and was accompanied by increased happiness indices for each student. Subsequent implementation of the two types of stimuli indicated that preferred stimuli based on preference assessments were more consistently accompanied by increased happiness indices than were preferred stimuli based on staff opinion. Social validity measures supported the definition of happiness, in that raters' subjective opinions of the students' happiness coincided with the observed happiness indices. Results are discussed regarding the importance and practical implications of using preference assessments for determining stimuli for increasing happiness indices. Future research areas are suggested, focusing on increasing happiness and other quality-of-life indicators during the daily routines of people with profound disabilities.  相似文献   
796.
Methamphetamine and scopolamine were studied in monkeys responding under a multiple fixed-ratio fixed-interval schedule of reinforcement. A response on any one of six levers could satisfy the schedule requirements. Variability of response location was evaluated in terms of switches, where a switch was defined as a response on one lever followed by a response on a different lever. Under baseline conditions the fixed-ratio schedule generated a high rate of responding and a low level of variability, while the fixed-interval schedule generated a low rate of responding and a high level of variability. Both methamphetamine (0.1 to 0.5 mg/kg) and scopolamine (2.4 to 240 microgram/kg) decreased overall response rate and increased variability of response location in each component of the multiple schedule with increasing doses of drug. At lower doses both drugs were found to decrease rate without affecting response variability.  相似文献   
797.
The reliability of alcohol abusers' retrospective self-reports was evaluated using a time-line follow-back interview technique. Independent groups of male subjects were interviewed in three different treatment settings (outpatient,n=12; inpatient,n=12; residential,n=12) on two separate occasions to assess the test-retest reliability of their self-reports of daily drinking and related events occurring 1 year prior to treatment. Correlational and scatterplot analyses generally showed a high correlation and low discrepancy between the two sets of interview responses for all groups. However, since some population differences were found in the reliability of reports for some variables, further research is needed to delineate the conditions under which reliable and valid retrospective self-reports can be obtained from different populations of alcohol abusers.This research was supported, in part, by Grant No. AA07072 from the National Institute on Alcohol Abuse and Alcoholism to Vanderbilt University.  相似文献   
798.
Thirteen master pigeons were exposed to multiple schedules in which reinforcement frequency (Experiment I) or duration (Experiment II) was varied. In Phases 1 and 3 of Experiment I, the values of the first and second components' random-interval schedules were 33 and 99 seconds, respectively. In Phase 2, these values were 99 seconds for both components. In Experiment II, a random-interval 33-second schedule was associated with each component. During Phases 1 and 3, the first and second components had hopper durations of 7.5 and 2.5 seconds respectively. During Phase 2, both components' hopper durations were 2.5 seconds. In each experiment, positive contrast obtained for about half the master subjects. The rest showed a rate increase in both components (positive induction). Each master subject's key colors and reinforcers were synchronously presented on a response-independent basis to a yoked control. Richer component key-pecking occurred during each experiment's Phases 1 and 3 among half these subjects. However, none responded during the contrast condition (unchanged component of each experiment's Phase 2). From this it is inferred that autoshaping did not contribute to the contrast and induction findings among master birds. Little evidence of local contrast (highest rate at beginning of richer component) was found in any subject. These data show that (a) contrast can occur independently from autoshaping, (b) contrast assays during equal-valued components may produce induction, (c) local contrast in multiple schedules often does not occur, and (d) differential hopper durations can produce autoshaping and contrast.  相似文献   
799.
The effectiveness of a mastery criterion, lecture-based training program for teaching behavior modification to sheltered workshop personnel was evaluated. Staff performance was assessed in terms of: (1) verbal proficiency, as determined from a pre- and posttraining written exam, and (2) application proficiency, as measured by the frequency and appropriateness of staff responses to client behaviors. A direct count was made of the number of positive, negative, and neutral statements following client appropriate and inappropriate behaviors, and the number and type of client behaviors ignored. Thus, it was possible to determine the extent of generalization from classroom to applied settings, as well as the appropriateness of lectures for training specific performance skills. Lecture units introduced stimulus control procedures, shaping-chaining, and contingency management. Characteristic features of the training program were frequent testing, study objectives, immediate remediation, and contingent reinforcement. Verbal instruction was shown to be effective in improving subjects' verbal skills concerning behavior-modification principles, while only partially effective in improving application skills. There was an increase in the total number of staff-client interactions observed for all subjects, but only two of the response classes emphasized in the training program (reinforcing desirable client behavior and ignoring undesirable behavior) showed considerable improvement over pretraining levels. Despite this partial improvement, verbal instruction alone was shown to be insufficient for teaching the full range of behavior-modification skills required to function effectively in applied settings.  相似文献   
800.
项目反应理论中参数估计程序的实现,一直是研究现代测量理论的学者们关注的问题。该研究从理论上探讨了多级模型参数估计的实现途径,并模拟了5批不同数量及分布情形的项目及被试参数,生成相应的原始得分矩阵,对自编程序及国际流行的相关程序进行了严格的比较校验,验证结果证明本程序具有精确、稳定的性能,并且发现被试量太少将影响参数估计的精确性及稳定性  相似文献   
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