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141.
Science and Engineering Ethics - This work describes the perceptions that Industrial Engineering students have regarding Colombian firms’ corporate social responsibility (CSR) practices. It...  相似文献   
142.
Aggressive biting of an inanimate target by mice was studied. Males attacked the bite-target more frequently than females, but this difference disappeared after castration when the response rate of the males approached that of the females. Ovariectomizing the females had little effect on their bite-attack frequencies. Subsequent androgen injections restored the biting-attack frequency of the castrated males to preoperative levels but had little effect on the intact males. Estrogen had little effect on the response frequency of the females, whereas androgen produced a slight increase in their bite-attack frequency. Results indicate that androgen is critical for the maintenance of this aggressive response and that the single subject paradigm utilized in this study was a sensitive measure of aggressive tendencies in mice.  相似文献   
143.
Reproductive activity has been the behavior of choice for research in behavioral endocrinology. Why this is so and the consequences to the study of aggression and to behavioral endocrinology in general are explored.  相似文献   
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Zaff JF  Blount RL  Phillips L  Cohen L 《Adolescence》2002,37(148):751-773
Much coping research has been conducted comparing members of different ethnic groups using discrete racial classifications. However, the past two decades have seen the construct of ethnicity evolve into a complex variable that must be assessed in a more comprehensive way. This study explored how ethnicity, a discrete variable, and the continuous variables of a person's ethnic identity and self-construal contribute to the use of particular coping strategies across various situations. One hundred twelve seventh graders (67 African Americans and 45 Caucasian Americans) from three suburban middle schools completed questionnaires assessing ethnic identity, self-construal, and coping strategies for medical, test, and social criticism stressors. Results supported the hypothesis that ethnicity as a discrete variable is not associated with coping, but that ethnic identity and self-construal are. It was also found that high scores on the ethnic identity and self-construal scales were indicative of more positive psychological adjustment. Implications for future research and methodological considerations are discussed.  相似文献   
146.
A field experiment was conducted to assess the effects of preemployment interventions on newly hired telemarketers. The procedures used were a realistic job preview (RJP), an expectation-lowering procedure (ELP), a combination (RJP & ELP), and the control condition (minimal socialization). While we know these procedures enhance the integration of newcomers to an organization, we do not know the optimal combination of RJP and ELP in the employee socialization process. The three procedures yielded relatively lower expectations than did the control group. Participants in the experimental conditions (ELP, RJP, and ELP & RJP) reported significantly lower expectations than did the control group. The lowered expectations, however, did not result in higher retention rates in all of the conditions. The RJP & ELP combination resulted in the largest number of days worked, the major criterion of interest in this study. There was no significant difference in number of days worked between the control group and the RJP group. The current study indicates that a non-job-specific ELP in combination with an RJP may exceed the benefits of an RJP or an ELP used alone. Furthermore, organizational implications regarding the different procedures are discussed.  相似文献   
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In an 18-month prospective study, community-dwelling older adults, including both spousal caregivers of dementia patients and noncaregiving controls, were examined. Participants were selected on the basis of the presence or absence of chronic depressive symptoms that exceeded a cutoff score for clinically relevant depressive symptoms on a self-report symptom measure. Compared with nondepressed older adults, those with chronic, mild depressive symptoms had poorer T cell responses to 2 mitogens from baseline to follow-up. Additionally, among individuals with depressive symptoms, older age was associated with the poorest blastogenic response to the mitogens at follow-up. These findings extend the association between depression and immune function to community-dwelling older adults with chronic, mild depressive symptoms.  相似文献   
149.
Experiments have shown that human and nonhuman subjects are capable of performing new arbitrary stimulus-stimulus relations without error. When subjects that are experienced with matching-to-sample procedures are presented with a novel sample, a novel comparison, and a familiar comparison, most respond by correctly selecting the novel comparison in the presence of the new sample. This exclusion paradigm was expanded with two California sea lions that had previously formed two 10-member equivalence classes in a matching-to-sample procedure. Rather than being presented with a novel sample on a given trial, the sea lions were presented with a randomly selected familiar member of one class as the sample. One of the comparisons was a randomly selected familiar member of the alternative class, and the other was a novel stimulus. When required to choose which comparison matched the sample, the subjects reliably rejected the familiar comparison, and instead selected the unfamiliar one. Next, the sea lions were presented with transfer problems that could not be solved by exclusion; they immediately grouped the new stimuli into the appropriate classes. These findings show that exclusion procedures can rapidly generate new stimulus relations that can be used to expand stimulus classes.  相似文献   
150.
The auditory perceptual abilities of male black-capped chickadees (Poecile atricapilla) were examined using an operant go/no-go discrimination among 16 individual vocalizations recorded at 5 m. The birds learned to discriminate about equally well among eight male chickadee fee-bee songs and eight female zebra finch (Taeniopygia guttata) distance calls. These results do not indicate that chickadees have a species-specific advantage in individual recognition for conspecific over heterospecific vocalizations. We then transferred the chickadees to a discrimination of the same songs and calls rerecorded at a moderate distance. These results showed accurate transfer of discrimination from 16 vocalizations recorded at 5 m to novel versions of the same 16 songs and calls rerecorded at 25 m. That is, chickadees recognized individual songs and calls despite degradation produced by rerecording at 25 m. Identifying individual vocalizations despite their transformation by distance cues is here described as a biologically important example of perceptual constancy.  相似文献   
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