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D. Z. Phillips 《Philosophical Investigations》1995,18(2):156-161
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Journal of Philosophical Logic - This paper is concerned with counterfactual logic and its implications for the modal status of mathematical claims. It is most directly a response to an ambitious... 相似文献
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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
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D. Caroline Blanchard Nina K. Popova Irina Z. Plyusnina Irina L. Velichko Desiree Campbell Robert J. Blanchard Julia Nikulina Ella M. Nikulina 《Aggressive behavior》1994,20(5):387-397
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
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Cerebral blood flow in 5‐ to 8‐month‐olds: Regional tissue maturity is associated with infant affect
M. Catalina Camacho Lucy S. King Amar Ojha Cheyenne M. Garcia Lucinda M. Sisk Anna C. Cichocki Kathryn L. Humphreys Ian H. Gotlib 《Developmental science》2020,23(5)
Infancy is marked by rapid neural and emotional development. The relation between brain function and emotion in infancy, however, is not well understood. Methods for measuring brain function predominantly rely on the BOLD signal; however, interpretation of the BOLD signal in infancy is challenging because the neuronal‐hemodynamic relation is immature. Regional cerebral blood flow (rCBF) provides a context for the infant BOLD signal and can yield insight into the developmental maturity of brain regions that may support affective behaviors. This study aims to elucidate the relations among rCBF, age, and emotion in infancy. One hundred and seven mothers reported their infants' (infant age M ± SD = 6.14 ± 0.51 months) temperament. A subsample of infants completed MRI scans, 38 of whom produced usable perfusion MRI during natural sleep to quantify rCBF. Mother‐infant dyads completed the repeated Still‐Face Paradigm, from which infant affect reactivity and recovery to stress were quantified. We tested associations of infant age at scan, temperament factor scores, and observed affect reactivity and recovery with voxel‐wise rCBF. Infant age was positively associated with CBF in nearly all voxels, with peaks located in sensory cortices and the ventral prefrontal cortex, supporting the formulation that rCBF is an indicator of tissue maturity. Temperamental Negative Affect and recovery of positive affect following a stressor were positively associated with rCBF in several cortical and subcortical limbic regions, including the orbitofrontal cortex and inferior frontal gyrus. This finding yields insight into the nature of affective neurodevelopment during infancy. Specifically, infants with relatively increased prefrontal cortex maturity may evidence a disposition toward greater negative affect and negative reactivity in their daily lives yet show better recovery of positive affect following a social stressor. 相似文献
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This article examines the usefulness of the Family Assessment Device(FAD) in assessing family functioning with school-aged children (under 12 years of age) compared to children 12 and older and mothers. FAD reports from 194 children with asthma (132 under 12 years; 62 12 years and older) were evaluated in comparison to mothers' FAD reports as well as mothers' reports on two other family functioning measures: the Family Inventory of Life Events (FILE) and the Impact on Family (IOF) scale, both relevant to functioning in families with children with asthma. Although FAD scale reliabilities were lowest in younger children (alpha = 48-.79), good concurrent validity was found with mothers' reports on the three different measures of family functioning. Older childrens' FAD scales showed good reliability (> .70) but poorer agreement with the various maternal measures. With modifications to make items more structured and simplified, the FAD could be tried with younger children, although documentation of improved reliability is needed before more widespread use with school-aged children is advocated. The measure already shows good agreement with maternal report in this younger age group, which likely would be strengthened with improved reliability. FAD reports in older children correlated less well with maternal measures, but may represent nonredundant information on family health from an independent perspective and are worth considering in addition to mothers' perspectives. 相似文献