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61.
62.
Selective breeding of wild rats over many generations on the basis of low or high defensive threat and attack to human approach and contact has produced highly polarized “domesticated” and “wild-type” animals. Because the selection procedure selectively involves these two defense patterns, and these clearly differ in the two groups, it is of interest to determine if other, nonselected, defensive behaviors to threat stimuli also change. “Domesticated” and “wild-type” rats of the thirty-fifth generation were run in a fear defense test battery (F/DTB) to systematically evaluate defensive behaviors to a variety of present threat stimuli. “Domesticated” rats showed reduced avoidance and slower flight speed to an approaching experimenter, reduced jump/startle response to handelap and dorsal contact, less vocalization and boxing to vibrissae stimulation or to an anesthetized conspecific, and reduced defensiveness to an attempted pickup by the experimenter. These results indicate that selective bi-directional breeding for defensive threat and attack to human approach and contact produces group differences in a variety of defensive behaviors, and in defensiveness to stimuli other than those on which the selection was based. © 1994 Wiley-Liss, Inc.  相似文献   
63.
The equality of two group variances is frequently tested in experiments. However, criticisms of null hypothesis statistical testing on means have recently arisen and there is interest in other types of statistical tests of hypotheses, such as superiority/non-inferiority and equivalence. Although these tests have become more common in psychology and social sciences, the corresponding sample size estimation for these tests is rarely discussed, especially when the sampling unit costs are unequal or group sizes are unequal for two groups. Thus, for finding optimal sample size, the present study derived an initial allocation by approximating the percentiles of an F distribution with the percentiles of the standard normal distribution and used the exhaustion algorithm to select the best combination of group sizes, thereby ensuring the resulting power reaches the designated level and is maximal with a minimal total cost. In this manner, optimization of sample size planning is achieved. The proposed sample size determination has a wide range of applications and is efficient in terms of Type I errors and statistical power in simulations. Finally, an illustrative example from a report by the Health Survey for England, 1995–1997, is presented using hypertension data. For ease of application, four R Shiny apps are provided and benchmarks for setting equivalence margins are suggested.  相似文献   
64.
This study examined the association between grandparental co-residence and child academic and behavioral outcomes using a sample from Shanghai, China (n = 1,763), and was built on two theoretical perspectives: intergenerational solidarity theory and the contextual model of family stress. These models integrate the impact of residential and relational proximity to grandparents on child well-being and underscore the importance of family context. This study also explored the moderating effects of family resources using proxies that prior theoretical and empirical studies have found to be important to such associations: family income, parental education, hukou status, and subjective social status. Results indicated that among families without co-residing grandparents, rural and low-income parents reported their children to have more externalizing behavioral issues than their respective urban and non-low-income counterparts. In addition, children who resided in poorly resourced families (i.e., low family income, low parental education, low subjective social status, or rural hukou status) tended to benefit from living with grandparents compared to their well-resourced counterparts in terms of lower externalizing and internalizing behaviors reported by teachers. These results do not negate the potential beneficial effects of living with grandparents for children in well-resourced environments. Implications for practice and policy, as well as future research directions, are discussed.  相似文献   
65.
The Performance Diagnostic Checklist-Human Services (PDC-HS) is an informant-based tool designed to identify the variables contributing to poor employee performance in human service settings, such as clinics, schools, and residential facilities. Upon completion of the tool, an intervention indicated by PDC-HS results is used to improve employee performance. To date, the PDC-HS has been used in a number of studies. This review describes the existing research on the PDC-HS and provides suggestions for future research.  相似文献   
66.
Abstract

Transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) has been demonstrated to modulate the motor performance of both healthy individuals and patients with neuromuscular disorders. However, the effect of tDCS on motor control of multiple muscles, which is a prerequisite to change in motor performance, is currently unknown. Using dimensionality reduction analysis, we investigated whether bilateral tDCS over M1 modulates the coordinated activity of 12 muscles. Fifteen healthy men participated in this randomized, double-blind crossover study. Each participant received a 20-min sham and 2-mA stimulation bilaterally over M1 (anode on the right M1 and cathode on the left M1), with a minimum washout period of 4?days. Muscle activation and end-point kinematics were evaluated during a task where participants reached out to a marked target with non-dominant hand as fast as possible, before and immediately after tDCS application. We found decreased similarity in motor modularity and significant changes in muscle activation in a specific motor module, particularly when reaching out to a target placed within arm’s length and improved smoothness index of movement only following 2-mA stimulation. These findings indicate that clinicians and researchers need to consider the simultaneous effect of bilateral tDCS over M1 on multiple muscles when they establish tDCS protocol to change in motor performance of patients with neuromuscular deficits.  相似文献   
67.
68.
This research examined different conceptualisations and measurements of adaptability in a university context. We compared two approaches to adaptability: (1) personal attribute and (2) performance construct. In the extant literature, the former is dominated by self-report measures, whereas the latter is dominated by performance-based tasks. In two studies, we developed and tested the factorial structure of self-report adaptability measures and the factorial structure of performance-based tasks. Self-report measures of adaptability converged into two factors: adaptability and inflexibility. Performance-based metrics of adaptability did not converge, however. Self-reported and performance measures were unrelated, calling for a multitrait-multimethod approach to further evaluate construct validity of adaptability measurement. Self-reported adaptability was related to Big-5 personality, whilst performance-based adaptability was related to cognitive abilities.  相似文献   
69.
Behavior analysis procedures have been used to improve sports performance and enhance player safety across a wide variety of sports. The current study evaluated the effects of behavioral skills training on three common field hockey shots, a slap shot, drive, and sweep for young field hockey players. The procedures were evaluated in a multiple baseline across behaviors for three players. Results showed increases in each type of shot once intervention was implemented.  相似文献   
70.
The present study aims at testing the effects of cultural intelligence (metacognitive, cognitive, motivational and behavioural facets) onto job performance in expatriation (dimensions relevant to task, effort demonstration, leadership, discipline maintenance, communication, administrative and managerial responsibilities) mediated by cross-cultural adjustment (global, interactional and job facets). Data are collected via an electronic survey administered to French expatriates (N = 201) and further processed in SPSS 20.0 and Lisrel 8.80. An output latent variable model globally confirms a mediation hypothesis and leads to a number of original findings. Namely, motivational and behavioural facets of cultural intelligence have the largest effect onto job performance in expatriation, while metacognitive facet has no effect at all. As regards job performance itself, the task dimension is the least dependent upon cultural intelligence and cross-cultural adjustment as compared to job performance aspects relevant to workplace relationships and team management (e.g., communication or leadership performance). The results are discussed in terms of their novelty and several research perspectives are proposed.  相似文献   
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