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81.
Holbrook Allyson L.; Berent Matthew K.; Krosnick Jon A.; Visser Penny S.; Boninger David S. 《Canadian Metallurgical Quarterly》2005,88(5):749
People who attach personal importance to an attitude are especially knowledgeable about the attitude object. This article tests an explanation for this relation: that importance causes the accumulation of knowledge by inspiring selective exposure to and selective elaboration of relevant information. Nine studies showed that (a) after watching televised debates between presidential candidates, viewers were better able to remember the statements made on policy issues on which they had more personally important attitudes; (b) importance motivated selective exposure and selective elaboration: Greater personal importance was associated with better memory for relevant information encountered under controlled laboratory conditions, and manipulations eliminating opportunities for selective exposure and selective elaboration eliminated the importance-memory accuracy relation; and (c) people do not use perceptions of their knowledge volume to infer how important an attitude is to them, but importance does cause knowledge accumulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
We set out a new general framework for making inferences from neuroimaging data, which includes a standard approach to neuroimaging analysis, statistical parametric mapping (SPM), as a special case. The model offers numerous conceptual and statistical advantages that derive from analyzing data at the "cluster level" rather than the "voxel level" and from explicit modeling of the shape and position of clusters of activation. This provides a natural and principled way to pool data from nearby voxels for parameter and variance-component estimation. The model can also be viewed as performing a spatio-temporal cluster analysis. The parameters of the model are estimated using an expectation maximization (EM) algorithm. 相似文献
83.
84.
Sprecher Penny L.; Thomas Edwin R.; Huebner Lois A.; Norfleet Benjamin E.; Jacoby Keith E. 《Canadian Metallurgical Quarterly》1983,14(2):251
50 medical patients completed the State–Trait Anxiety Inventory before and after a physical examination, during which they were encouraged or not encouraged to discuss their health concerns. Results suggest that encouraging patients to disclose their underlying concerns and then confirming or discrediting these concerns are effective ways to reduce anxiety. Findings also indicate that many medical patients overestimate the severity of their physical ailments. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Felner Robert D.; Norton Penny L.; Cowen Emory L.; Farber Stephanie S. 《Canadian Metallurgical Quarterly》1981,12(4):446
Describes the development and evaluation of a preventively oriented crisis intervention program for young children. 57 primary grade children who were experiencing the crisis-predisposing events of parental death, divorce or remarriage, major elective surgery, or birth of a sibling were seen by trained nonprofessional child-aides in the school setting. Child-aides employed abreactive and problem-solving techniques during twice weekly meetings with Ss over a 6 wk period. Program Ss showed significant improvement on measures of school adjustment problems and competencies (Classroom Adjustment Rating Scale, Health Resources Inventory) and the State-Trait Anxiety Index for Children. Analyses indicate that the program was most effective with Ss for whom the life events seemed most crisis precipitating. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
I F Penny 《Journal of the science of food and agriculture》1974,25(10):1273-1284
Myofibrillar proteins from bovine muscle have been treated with a Ca2+ activated muscle proteinase and the consequent changes in these proteins have been examined by various techniques. Tropomyosin, α-actinin and troponin were substrates for the enzyme, the last losing its property of inhibiting actomyosin ATPase in the absence of Ca2+ ions. Actin and actomyosin were apparently not digested but the Mg2+-activated ATPase activity of actomyosin was less after treatment whereas the Ca2+-activated ATPase was unaffected. It is suggested that the observed destruction of the Z-bands of the myofibrils by this proteinase is due to its digestion of the α-actinin, rather than the actin component. 相似文献
87.
Exposure of pregnant guinea pigs to an environmental temperature of 42 degrees C for 1 hr daily on Days 20-24 of gestation resulted in a significant reduction in the birthweight and brainweight of newborn offspring. These deficits persisted to early maturity and were still evident at 250 days of age following behavioral testing. Although some degree of postnatal neurogenesis and brain growth had occurred, this was not sufficient to compensate for the retarding influence of prenatal hyperthermia. Heat stress was also observed to seriously impair learning performance on the original discrimination task and this tendency persisted over the subsequent 4 reversals for both initial and perseverative errors. Impaired learning performance was related to reduction in brainweight. Animals with lower brainweights made significantly more initial, perseverative and total number of errors over the 5 problems. In addition, 12 of the 14 behaviorally tested stressed progeny had brainweights that were at least 2 standard deviations below the mean of the controls and as a result were classified as micrencephalic. Although heat stressed animals showed a significant reduction in the number of amacrine synapses in the inner plexiform layer of the retina, performance differences were not atrributed to changes in synaptic organisation of the retinal circuitry or to visual or other ophthalmic defects, but brain function. Animals with higher mean maternal poststressing core temperatures gave birth to progeny which had smaller whole and part wet-brainweights. Examination of the effect of poststressing core temperature on brainweight revealed that brain growth, independent of bodyweight, was retarded when this temperature elevated above 41.5 degrees C. This represented a rise of approximately 2.1 degrees C above normal and for each 1 degree C rise above this temperature, brainweight was reduced by 0.4227 g of the control value. Analysis of the atmospheric content of the incubator during stressing sessions ruled out the possibility that changes in level of oxygen and carbon dioxide may have contributed to the retarding influence on fetal development and learning ability in the guinea pig. 相似文献
88.
David S. Powlson Penny R. Hirsch Philip C. Brookes 《Nutrient Cycling in Agroecosystems》2001,61(1-2):41-51
Soil is a large sink for organic carbon within the terrestrial biosphere. Practices which cause a decline in soil organic
matter cause CO2 release, in addition to damaging soil resilience and, often, agricultural productivity. The soil micro-organisms (collectively
the soil microbial biomass) are the agents of transformation of soil organic matter, nutrients and of most key soil processes.
Their activities are much influenced by soil physico-chemical and ecological interactions. This paper addresses two key issues.
Firstly, ways of managing, and the extent to which it is possible to manage, soil biological functions. Secondly, the methodologies
currently available for studying soil micro-organisms, and the functions they mediate, are discussed. It is concluded that,
as the world population develops in this new millennium, there will be an increased dependence upon biological processes in
soil to provide adequate crop nutrition for the majority of the world's farmers. Although a major increase in the use of artificial
fertilisers will be necessary on a global scale, this will not be an option for large numbers of farmers due to their poverty.
Instead they will rely on recycling of nutrients from animal and vegetable composts and urban wastes, and biological cycling
from nitrogen fixation and mycorrhizae. The challenge is to select the most appropriate topics for further research. Not all
aspects are likely to lead to significantly improved agricultural productivity, or sustainability within the foreseeable future.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
89.
Using typical and modified negative priming tasks, the selection-feature mismatch account of negative priming was tested. In the modified task, participants performed selections on the basis of a semantic feature (e.g., referent size). This procedure has been shown to enhance negative priming (P. A. MacDonald, S. Joordens, & K. N. Seergobin, 1999). Across 3 experiments, negative priming occurred only when the repeated item mismatched in terms of the feature used as the basis for selections. When the repeated item was congruent on the selection feature across the prime and probe displays, positive priming arose. This pattern of results appeared in both the ignored- and the attended-repetition conditions. Negative priming does not result from previously ignoring an item. These findings strongly support the selection-feature mismatch account of negative priming and refute both the distractor inhibition and the episodic-retrieval explanations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Patrick Buehler Mark Everingham Daniel P. Huttenlocher Andrew Zisserman 《International Journal of Computer Vision》2011,95(2):180-197
The goal of this work is to detect and track the articulated pose of a human in signing videos of more than one hour in length.
In particular we wish to accurately localise hands and arms, despite fast motion and a cluttered and changing background. 相似文献