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11.
When hooded rats with bilateral lesions of Krieg's Area 7 (parietal cortex) were trained to locomote toward visual targets in a runway, they ran less accurately than did controls, although unilaterals ran accurately. When flashing lights were presented unexpectedly during their run, bilateral parietals were less disrupted than were controls, but they failed to show total neglect. Unilateral parietals turned toward distracters on either side but turned preferentially toward distracters contralateral to the intact hemisphere, particularly when distracters occurred bilaterally and simultaneously. Effects due to the omission of expected distracters were similar in parietals and controls. Rat parietal cortex is not essential for the redirection of attention to stimuli notable for their unexpected presence or absence, but parietal cortex may resolve interhemispheric competition. Results suggest a homology between parietal cortex in rat and primate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
Higher testosterone levels are related to assertiveness and dominance. Given the relevance of those behavioral correlates to spouses' daily transactions, links between testosterone levels and marital interaction were explored among 92 newlywed couples. Marital problem-solving and social support transactions were assessed, and saliva was collected and assayed for testosterone. Whether marital behavior was related to husbands' and wives' testosterone levels was examined. The link between spouses' testosterone and their behavior was contingent on the partner's testosterone levels. Husbands exhibited more adaptive problem-solving behaviors and social support provision when husbands and wives were concordant for lower testosterone levels. In contrast, wives exhibited more adaptive support provision when spouses had discordant testosterone levels such that wives had higher levels and husbands had lower levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Working collaboratively, psychologist educators and trainers at the doctoral, internship, and postdoctoral levels; credentialers; practitioners; and students offer 8 proposals for psychologists to consider in recognizing, assessing, and intervening with problems of professional competence in students and practicing professionals. In the proposals, the authors address the following topics: definitions and categories; preparing the system; self-assessment; remediation; diversity; communication across various levels of the system; confidentiality; and ethical, regulatory, and legal underpinnings. They also propose future directions for the assessment of problems in professional competence in both students and practicing psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Theorists have predicted that repetition blindness (RB) should be absent for nonwords because they do not activate preexisting mental types. The authors hypothesized that RB would be observed for nonwords because RB can occur at a sublexical level. Four experiments showed that RB is observed for word-nonword pairs (noon noof), orthographically similar nonwords (glome glame), and identical repetitions (plass plass). More RB was found for words than for nonwords. Prior researchers may have failed to find RB for nonwords because display conditions that allow 2 words to be reliably encoded are insufficient for nonwords, or because observers coped with low ability to encode nonwords by using guessing strategies that do not require creating a mental type or tokenizing it. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
15.
The role of nitrogen dioxide in the selective reduction of NO by propane over a Cu-MFI zeolite is investigated. NO2 and NO reductions were carried out under similar conditions of reaction. In the presence of oxygen, the reduction of NO by C3H8 does not differ significantly from that of NO2. In the absence of oxygen, the reduction of NO2 by propane occurs with a partial decomposition of the nitric dioxide molecule. Such a decomposition leads to the formation of oxygen, which is responsible for the increase in catalytic activity by comparison with the same reaction performed with NO. NO2 formed and released in the gas phase during the reduction of NO by propane in the presence of oxygen does not play a predominant role in the catalytic process.  相似文献   
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The availability and salience of object attributes under haptic exploration, with and without vision, were assessed by 2 tasks in which Ss sorted objects that varied factorially in size, shape, texture, and hardness. In the directed-discrimination task, Ss were instructed to sort along a particular dimension. Although levels on all dimensions were easily discriminated, shape was relatively less so for haptic explorers without vision, as was hardness for those using vision and haptics. Size was least discriminable for both groups. In the free-sorting task, Ss were to sort objects by similarity. Three groups used haptic exploration only; these were differentiated by the experimenters' definition of object similarity: unbiased haptics, haptically biased haptics, haptics plus visual imagery. A 4th group used vision as well as haptics, with instructions like those of the unbiased haptics group. Results support the contention that the haptic and visual systems have distinct encoding pathways, with haptics oriented toward the encoding of substance rather the shape. This may reflect a direct influence of haptic exploratory procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
20.
Polysaccharide fractions were measured in coconuts at three stages of maturity, which corresponded to dietary usage in the Tokelau Islands of the South Pacific. Kernel was sequentially extracted with cold water (CW), hot water (HW) hot 0.5% ammonium oxalate (HOX), 1M H2 SO4 and 72% H2 SO4, and the monosaccharide compositions of the fractions determined. Total readily soluble fractions (CW+HW+HOX) were predominantly galactomannan, and decreased from 77% of the polysaccharide in the immature kernel to 8.8% of that in the mature kernel. Insoluble mannan increased during maturation to be the major polysaccharide component in mature kernel. This indicates that marked differences exist between the three stages of maturity examined, in the properties of their dietary fibre. The results suggest that in studies of diets in which coconut is a staple part, there is a need for careful definition of the coconut component with respect to maturity. Furthermore, they show the importance of using dietary fibre methods which are appropriate to the solubility characteristics of the indigestible polysaccharide.  相似文献   
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