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61.
The experiments were performed on adult male cats selected initially as good mousekillers. Cats were tested in pairs and each pair was introduced separately to the experimental compartment. The attitude toward the partner before and during the predatory competition test as well as superiority in catching and killing the mice, considered as an index of dominance, were registered. In the course of experiment five types of relations between the predatory dominance and aggressive behavior were observed. The concept of dominance as an outcome of several factors was discussed. It was concluded that predatory dominance is not based exclusively on aggressive mechanisms, as it may be formed and sustained without overt aggression.  相似文献   
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.
This paper reports on the reliability of children's responses on the Child and Adolescent Services Assessment (CASA) — a self-report instrument for use with 8– to 18-year-olds that gathers information about services used to address mental health problems. Findings were based on interviews completed by 77 children at a one week test-retest interval. Results showed that reports of lifetime service use were as reliable as were reports of service use in the preceding three months. Children reported restrictive and intrusive services more reliably than services that were provided in their natural environment. Reliability appeared to be associated more strongly with characteristics of the type of service than with characteristics of the child. Children also could report reliably on some details about their encounters with service providers (e.g., length of stay, number of visits, and onset of service use).  相似文献   
64.
What accounts for individual differences in the sort of knowledge that people may draw on in everyday cognitive tasks, such as deciding whom to vote for in a presidential election, how to invest money in the stock market, or what team to bet on in a friendly wager? In a large sample of undergraduate students, we investigated correlates of individual differences in recently acquired knowledge of current events in domains such as politics, business, and sports. Structural equation modeling revealed two predictive pathways: one involving cognitive ability factors and the other involving two major nonability factors (personality and interests). The results of this study add to what is known about the sources of individual differences in knowledge and are interpreted in the context of theoretical conceptions of adult intelligence that emphasize the centrality and importance of knowledge (e.g., Ackerman, 1996; Cattell, 1971).  相似文献   
65.
By atomic-scale high-angle annular dark-field scanning transmission electron microscopy, the long-period stacking ordered (LPSO) structures in a near-equilibrium Mg97Zn1Y2 (at.%) alloy have been characterised. In addition to 18R and 14H, new polytypes of LPSO structures are analysed and determined as 60R, 78R, 26H, 96R, 38H, 40H, 108H and 246R. All of these LPSO structures feature AB′C′A building blocks with two Mg layers and three Mg layers sandwiched between them. The Bravais lattices and space groups of new polytypes of LPSO structures were easily determined via the newly introduced method. A structural relationship between the LPSOs is proposed.  相似文献   
66.
This longitudinal study examined the reciprocal effects of the frequency of parent–adolescent communication on tobacco-related issues (smoking-specific communication), and adolescents’ smoking. Participants were 428 Dutch older and younger siblings between 13 and 16 years old. Smoking-specific communication did not affect youth smoking in general; however, among younger, but not older, siblings, smoking-specific communication was associated with a higher likelihood of smoking over time. In addition, when adolescents already smoked parents started to talk more frequently about smoking-related issues with their older and younger adolescents later on. Neither the quality of smoking-specific communication, the quality of parent–adolescent relationship, nor parental smoking moderated these reciprocal effects. In conclusion, prevention campaigns encouraging parents to undertake smoking-specific communication might not be desirable.  相似文献   
67.
Abstract

This is a supplement to the Rorschach bibliographies published by Dr. P. E. Vernon; the last of these was published in the January 1937 issue of the Rorachach Research Exchange. All available articles which are not contained in Dr. Vernon's bibliography are included. Those articles which have appeared in the Rorschach Research Exchange but which have not appeared elsewhere are omitted.  相似文献   
68.
To understand the Invar anomalies, such as negative thermal expansion and spontaneous magnetization, we have applied our recently developed thermodynamic framework for a system with itinerant-electron magnetism to the ordered Fe3Pt. The framework has coherently predicted the finite temperature intermixing between the fully ferromagnetic (FM) configuration and the spin-flipping configurations (SFCs). We have also discovered a tri-critical point at which a high-temperature second-order phase transition, between the fully ordered FM phase and the paramagnetic phase which is disordered due to SFCs, becomes first order at low temperatures.  相似文献   
69.
Magnesium oxide (MgO) films and particles have been collected by pressurised filtration of a Mg-8.6wt%Al-0.67wt%Zn (AZ91D) alloy melt. The morphology of the oxides and their interfaces with the α-Mg phase were investigated by high-resolution transmission electron microscopy. It was found that the oxide films consisted of large numbers of sub-micrometre-sized MgO particles, and that melt shearing can effectively break up the oxide films and disperse the oxide particles. For the first time, orientation relationships (ORs) of OR I: [1?1?1]MgO~2° from (0?0?0?1)α-Mg and (0?1?1)MgO?//[2?1?1?0)α-Mg; and OR II: (1?1?1)MgO//(1?1?0?1)α-Mg and [0?1?1]MgO//[1?2?1?1]α-Mg, were observed between the MgO particles and the α-Mg matrix. The calculated Bramfitt planar disregistries were 5.5% and 2.5% for the two ORs, respectively, indicating good lattice matching between MgO and α-Mg at the interface. With the evidence of grain refinement effect observed in the sheared AZ91D magnesium alloy, the possibility of MgO particles to act as potent nucleants for heterogeneous nucleation of α-Mg grains is discussed in terms of the crystallographic criterion.  相似文献   
70.
Functional magnetic resonance imaging (fMRI) was used to compare directly episodic encoding and retrieval. During encoding, subjects studied visually presented words and reported via keypress whether each word represented a pleasant or unpleasant concept (intentional, deep encoding). During the retrieval phase, subjects indicated (via keypress) whether visually presented words had previously been studied. No reliable differences were found during the recognition phase for words that had been previously studied and those that had not been studied. Areas preferentially active during encoding (relative to retrieval) included left superior frontal cortex, medial frontal cortex, left superior temporal cortex, posterior cingulate, left parahippocampal gyrus, and left inferior frontal gyrus. Regions more active in retrieval than encoding included bilateral inferior parietal cortex, bilateral precuneus, right frontal polar cortex, right dorsolateral prefrontal cortex, and right inferior frontal/insular cortex.  相似文献   
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