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981.
In Experiment 1, male rats were exposed to either aggressive (i.e., alpha) or nonaggressive conspecific colonies and tested 24 h later, with or without alpha odors, for freezing behavior and burying of a wall prod that had been the source of a brief electric shock. The results indicated that prior defeat experience and the presence of alpha odors alone during testing had no significant effects, but the combination of prior defeat and alpha-odor testing significantly decreased burying and increased freezing behavior. In Experiment 2, we examined the effects of noncontact exposure to a cat, as a predatory Stressor, during subsequent prod-shock tests involving the presence or absence of cat odors. Exposure to a cat failed to disrupt later prod burying and did not produce freezing. However, the presence of cat odors during testing significantly reduced the amount of defensive burying,without resulting in an increment in freezing. In Experiment 3, rats were given 1, 5, or 30 inescapable preshocks in the presence of either cat odors or a hedonically neutral citronella odor and were tested 24 h later for prod burying and freezing with or without these odors. Both the cat and the citronella odors resulted in a significant reduction in burying and an increase in freezing for rats given 5 and 30 preshocks and tested in the presence of these respective conditioned odors. For the groups that were given 5 preshocks, preshock and later testing in the presence of cat odors resulted in significantly less prod burying and more freezing than for rats that were preshocked and tested in the presence of citronella. The findings of these three ethoexperimental studies are discussed in terms of the learned-helplessness theory, the stress-coping-fear-defense (SCFD) theory, and the concept of selective CS-US associability.  相似文献   
982.
983.
Findings are presented from the second phase of a UK longitudinal study of 33 gay father, 35 lesbian mother, and 43 heterosexual parent families when their adopted children reached early adolescence. Participants predominantly lived in urban/suburban areas and were mostly white and well-educated. Standardized interviews, observations, and questionnaires of parental mental health, parent–child relationships, and adolescent adjustment were administered to parents, children, and teachers between 2016 and 2018. There were few differences between family types. However, adjustment problems had increased in all family types, with better parenting quality and parental mental health associated with fewer adjustment problems. The findings contribute to adoption policy and practice, and to theoretical understanding of the role of parental gender in child development.  相似文献   
984.
Incorporating the academic engaged time model, the present study investigated behavioral differences between high- and low-achieving inner-city children. Two hundred observations of “on-task”-“off task” behavior of 136 children within the elementary grades (1 through 6) were noted during reading and mathematics lessons. Findings suggested that high- and low-achieving inner-city children spend a large proportion of time actively engaged in academic tasks, with high achievers spending somewhat more time than low achievers. No significant developmental trends were noted, and discrepant academic attainment levels of children are discussed in terms of an “academic learning time” model.  相似文献   
985.
986.
987.
It is increasingly important for government agencies to collaborate across jurisdictional and functional boundaries. Interorganizational systems supporting interagency collaboration must accommodate a wide range of factors from the external environment and participating organizations as part of their design and operation. This paper presents the findings from a case study of CapWIN, a collaborative network created to enable first responders to share information across jurisdictional and functional boundaries as they work together during emergencies and other critical events. The study examines how aspects of the external environment and the agency context impeded or facilitated the CapWIN collaborative network and the interorganizational system (IOS) that supports it. We identify factors affecting information sharing and collaborative processes, and describe how these factors interact to enable and constrain an IOS. The paper concludes with suggestions for further research on the interplay of environmental, organizational, and technical aspects of interagency collaboration networks as they evolve over time.  相似文献   
988.
Abstract

Nine males (age 24.7 ± 2.1 years, height 175.3 ± 5.5 cm, body mass 80.8 ± 7.2 kg, power clean 1-RM 97.1 ± 6.36 kg, squat 1-RM = 138.3 ± 20.9 kg) participated in this study. On day 1, the participants performed a one-repetition maximum (1-RM) in the power clean and the squat. On days 2, 3, and 4, participants performed the power clean, squat or jump squat. Loading for the power clean ranged from 30% to 90% of the participant's power clean 1-RM and loading for the squat and jump squat ranged from 0% to 90% of the participant's squat 1-RM, all at 10% increments. Peak force, velocity, and power were calculated for the bar, body, and system (bar + body) for all power clean, squat, and jump squat trials. Results indicate that peak power for the bar, body, and system is differentially affected by load and movement pattern. When using the power clean, squat or jump squat for training, the optimal load in each exercise may vary. Throwing athletes or weightlifters may be most concerned with bar power, but jumpers or sprinters may be more concerned with body or system power. Thus, the exercise type and load vary according to the desired stimulus.  相似文献   
989.
OBJECTIVE: An updated systematic review was carried out of research studies looking at the value and impact of library services on health outcomes for patients and time saved by health professionals. METHODS: A comprehensive systematic search was undertaken of the published literature to September 2003 in ERIC, LISA, MEDLINE, PREMEDLINE, EMBASE, the Cochrane Controlled Trials Register and Google. Some handsearching was carried out, reference lists were scanned and experts in the field were contacted. Twenty-eight research studies of professionally led libraries for health-care staff, including clinical librarian projects, met the inclusion criterion of at least one health or 'time saved' outcome. Papers were critically appraised using internationally accepted criteria. Data were extracted and results were summarised using a narrative format as the studies were heterogeneous and precluded a statistical analysis. RESULTS: There is evidence of impact from both traditional and clinical librarian services. The higher quality studies of traditional services measured impacts of 37-97% on general patient care, 10-31% on diagnosis, 20-51% on choice of tests, 27-45% on choice of therapy and 10-19% on reduced length of stay. Four studies of clinical librarian projects suggested that professionals saved time as a result of clinical librarian input, and two of these studies showed evidence of cost-effectiveness. However, the clinical librarian studies were generally smaller, with poorer quality standards. CONCLUSIONS: Research studies suggest that professionally led library services have an impact on health outcomes for patients and may lead to time savings for health-care professionals. The available studies vary greatly in quality but the better quality studies also suggest positive impacts. Good practice can be gathered from these studies to guide the development of a pragmatic survey for library services that includes the direct effects for patients among the outcome measures.  相似文献   
990.
Early childhood is a sensitive period for learning and social skill development. The maturation of cerebral regions underlying social processing lays the foundation for later social-emotional competence. This study explored myelin changes in social brain regions and their association with changes in parent-rated social-emotional development in a cohort of 129 children (64 females, 0–36 months, 77 White). Results reveal a steep increase in myelination throughout the social brain in the first 3 years of life that is significantly associated with social-emotional development scores. These findings add knowledge to the emerging picture of social brain development by describing neural underpinnings of human social behavior. They can contribute to identifying age-/stage-appropriate early life factors in this developmental domain.  相似文献   
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