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31.
Current Psychology - Valence and approach-avoidance motivation are two distinct but closely related components of affect. However, little is known about how these two processes evolve and covary in...  相似文献   
32.
Salena  Matthew G.  Turko  Andy J.  Singh  Angad  Pathak  Avani  Hughes  Emily  Brown  Culum  Balshine  Sigal 《Animal cognition》2021,24(3):395-406
Animal Cognition - With over 30,000 recognized species, fishes exhibit an extraordinary variety of morphological, behavioural, and life-history traits. The field of fish cognition has grown...  相似文献   
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Kidd SA  Kral MJ 《Adolescence》2002,37(146):411-430
This study presents the results of a qualitative analysis of the narratives of 29 street youth in which they describe their experiences with, and understanding of, suicide. A history of attempted suicide was reported by 76% of the participants and the analysis revealed themes of isolation, rejection/betrayal, lack of control, and most centrally, low self-worth as forming the basis of their experiences concerning suicide. Additionally it was found that trading sex, in which most participants had been or were currently involved, was linked with their suicidal experiences and may account for the high attempt rate. Finally, variables related to suicide were found that have not been examined previously in the literature on street youth, including loss of control, assault during prostituted sex, drug abuse as a "slow suicide," and breakups in intimate relationships.  相似文献   
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The present study examined the influence of short- and long-term chronic intermittent immobilization stress throughout the brain and on the adrenal medulla of intact rats using Fos-like immunoreactivity (Fos-LI) as a marker of cellular activation. The effect of adreno-medullectomy on the central nervous system (CNS) response to chronic immobilization stress was also examined. It was found that control unoperated, unstressed rats had no Fos-LI cells in the brain or in the adrenal medulla. In intact rats, neither short term (1 week) nor long term (4 weeks) chronic intermittent immobilization stress produced significant increases in Fos-LI in the CNS compared with control animals. However, marked increase in the number of Fos-LI cells was observed in the adrenal medulla of animals stressed for 4 weeks compared with control, unstressed animals or those stressed for 1 or 2 weeks. In adreno-medullectomised rats, 4 weeks, but not 1 week, chronic immobilization stress produced significant increases in numbers of Fos-LI neurons in the paraventricular hypothalamic and supraoptic nuclei and the medial amygdala compared with intact animals stressed for a similar period of time. It is concluded that long term stress produces chronic Fos-LI in the adrenal medulla and that adreno-medullectomy increases the Fos response of the PVN, supraoptic nucleus and medial amygdala to long term stress.  相似文献   
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Key pecking by 3 pigeons was maintained by a multiple fixed-ratio 10, fixed-ratio 30, fixed-ratio 90 schedule of food presentation. Components differed with respect to amount of reinforcement, such that the unit price was 10 responses per 1-s access to food. Acute administration of morphine, l-methadone, and cocaine dose-dependently decreased overall response rates in each of the components. When a rate decreasing dose of morphine was administered daily, tolerance, as measured by an increase in the dose that reduced response rates to 50% of control (i.e., the ED50 value), developed in each of the components; however, the degree of tolerance was smallest in the fixed-ratio 90 component (i.e., the ED50 value increased the least). When the l-methadone dose-effect curve was redetermined during the chronic morphine phase, the degree of cross-tolerance conferred to l-methadone was similar across components, suggesting that behavioral variables may not influence the degree of cross-tolerance between opioids. During the chronic phase, the cocaine dose-effect curve shifted to the right for 2 pigeons and to the left for 1 pigeon, which is consistent with predictions based on the lack of pharmacological similarity between morphine and cocaine. When the morphine, l-methadone, and cocaine dose-effect curves were redetermined after chronic morphine administration ended, the morphine and l-methadone ED50s replicated those obtained prior to chronic morphine administration. The morphine data suggest that the fixed-ratio value (i.e., the absolute output) determines the degree of tolerance and not the unit price.  相似文献   
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This study explored a proposed relationship between the corporate ethical values and cynicism of 195 working students. Analysis indicated students' perceived ethical values were negatively related to individual cynicism after accounting for several variables.  相似文献   
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Optimism and pessimism are personality variables that have repeatedly been shown to affect health, job performance, and social relationships. Various instruments purport to measure these dispositions that differ substantially in their theoretical and measurement models. While research has examined relations between subsets of these measures, their unique predictive ability has been neglected. Three sequential studies evaluated the interrelation and predictive ability of the three most utilized instruments, the Life Orientation Test (LOT), the O/P Instrument (OPI) and variants of the Attributional Style Questionnaire (ASQ). Consistent with expectations, measures sharing a future-expectancy component (LOT and OPI) were moderately related and most predictive of health, depression, and coping. ASQ measures were modestly related to the LOT and OPI and offered less consistent predictions.  相似文献   
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