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Handled (Day 1-22) and non-handled infantile Wistar rats were tested in maturity for the partial reinforcement extinction effect (PREE) and the partial punishment effect (PPE). In Experiments 1 and 2, mature male and female rats were trained to run in an alley for food reward on a 1-trial/day schedule. In the PREE paradigm (Experiment 1), the partially reinforced group (PRF) received reinforcement on a quasi-random 50% schedule, while the continuously reinforced group (CRF) received reinforcement on every trial. In the test stage, both groups were given extinction training. In the PPE paradigm (Experiment 2), the partially punished (PP) group received, together with continuous reinforcement, shocks on a quasirandom 50% schedule, while the continuously reinforced group was reinforced on every trial. In test, all animals were given both reinforcement and shock on every trial. In Experiment 1, PREE—i.e. increased resistance to extinction in the PRF as compared to the CRF group—was more pronounced in the handled animals. More specifically, no PREE was obtained in the non-handled males, and in the non-handled females the PREE was reduced compared to the handled females. The results of Experiment 2 revealed no effect of handling or sex on PPE, that is, increased resistance to punishment in the PP group as compared to the CRF group was evident in all four conditions. In Experiment 3, handled and non-handled male rats were tested for the PREE using a multi-trial procedure in an operant chamber. PREE was obtained in the handled but not in the non-handled animals. The implications of these results for the differential effects of handling on male and female rats and the distinction between the PREE and PPE paradigms are discussed.  相似文献   
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Suicide is a major public health concern, especially in adolescence. Identifying risk factors for suicide is important to effectively prevent such behavior. Depression is one of the most widely examined risk factors for suicidal risk. How depression and suicidal risk are related, however, is still not clear. This study tested a model with three key constructs of the interpersonal–psychological theory of suicidal behavior (IPTS)—perceived burdensomeness, thwarted belongingness, and nonsuicidal self‐injury (NSSI)—as mediators in the relationship between depression and suicidal risk among Chinese adolescents. Chinese high school students (N = 1,074; 54.2% male; Mage = 13.87 years, SD = 1.48) completed questionnaires assessing all study variables. Results suggested that perceived burdensomeness and NSSI partially mediated the relationship between depression and suicidal risk. Findings of this study emphasize the importance of the IPTS framework in understanding the possible mechanisms underlying the relationship between depression and suicidal risk, and suggest a possible avenue for suicide interventions.  相似文献   
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The new biomedical techniques of reproduction either currently available or being researched, such as sex predetermination of offspring, sperm banking, test tube conception with embryo transplant, development of artificial wombs and human cloning, allow greatly expanded choices in methods of procreation. A survey of attitudes among 2,138 adults, most of whom are in the early to middle stages of reproductive decision making, shows varying levels of acceptance towards the use of such techniques and towards priority values they would assign to ongoing research to perfect specific technorogies. Male-female variation in response patterns are analyzed along with racial and religious differences. Possible and probable impacts that widespread use of these new alternatives might have on the future of women in particular and on various aspects of society in general are discussed.  相似文献   
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