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61.
The scores of 1,200 undergraduates on Sarason's Test Anxiety Scale were factor analyzed. The analysis involved rotation to an orthogonal structure that produced 2 factors that accounted, respectively, for 53.45% and 31.50% of the total variance. Both cognitive "worry" and "emotionality" items loaded strongly on the 1st factor, which appears to reflect worry about oneself and one's performance on tests and a variety of physical and emotional consequences of this intense worry. The 2nd factor seems to reflect emotional distress in testing situations, but no worry or interference with performance, in persons who appear to lack a strong achievement orientation. Subscales based on these 2 factors were negatively correlated. Implications for the 2-component theory of test anxiety are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Annual growth increments were calculated for blue catfish (Ictalurus furcatus) and flathead catfish (Pylodictis olivaris) from the lower Mississippi River (LMR) to assess hypothesized relationships between fish growth and floodplain inundation as predicted by the Flood‐Pulse Concept. Variation in catfish growth increment was high for all age classes of both species, and growth increments were not consistently related to various measures of floodplain inundation. However, relationships became stronger, and usually direct, when water temperature was integrated with area and duration of floodplain inundation. Relationships were significant for four of six age classes for blue catfish, a species known to utilize floodplain habitats. Though similar in direction, relationships were weaker for flathead catfish, which is considered a more riverine species. Our results indicate the Flood‐Pulse Concept applies more strongly to temperate floodplain‐river ecosystems when thermal aspects of flood pulses are considered. We recommend that future management of the LMR should consider ways to ‘recouple’ the annual flood and thermal cycles. An adaptive management approach will allow further determination of important processes affecting fisheries production in the LMR. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
63.
Proposes that the moral evaluation process is, in part, based on reality and achievement evaluations. This proposition is suggested by certain similarities found between moral evaluations and the other 2 types. Implications are drawn regarding (a) dilemmas and conflicts in moral evaluation which arise from its dual foundations; (b) the different kinds of morality that evolve depending upon which more primary evaluative system becomes predominant; and (c) the susceptibility of moral evaluations to contamination by reality and achievement evaluations. (20 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
64.
Describes the case of a withdrawn adolescent male outpatient at a mental health clinic who was instructed to record his own verbal behavior. Consequences were implemented to increase the frequency of verbal responses. S "earned" his way out of the clinic by increasing his verbal behavior to an established criterion performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
65.
Administered the MMPI and 16 PF to 201 15-60 yr. old new admissions to a state mental hospital. Correlations between the 2 sets of scale scores were examined directly and by factor analysis. 3 common factors appeared to be represented to some extent in both instruments. The 16 PF appeared weak in the measurement of the more serious kinds of psychopathology, and had strongest loadings in a common factor identified with the validity scales of the MMPI. The 16 PF was found to measure 3 higher-order factors of personality not represented in the MMPI, but they do not appear highly relevant for assessment in a disturbed mental hospital population. Numerous significant relationships to psychiatrically relevant background variables were identified in analyses of profiles derived from both instruments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
Studied the magnitude and stability of individual differences in the amount of time required to achieve a criterion level of performance (time-to-criterion). Time-to-criterion was defined by (a) the amount of elapsed time and (b) the amount of on-task time required to attain the criterion. 90 8th graders were randomly assigned either to a mastery learning class in which all Ss were helped to attain an 85% mastery standard or to 1 of 2 nonmastery classes. Ss learned a 3-unit sequence of programmed material in matrix arithmetic. Results from the 82 Ss who completed the study indicate that time-to-criterion (defined in both manners) was an alterable human characteristic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
Presents general criteria for observation room windows. Various glazing materials available for proper lighting and the typical transmission and reflection characteristics of each, acoustical factors relating to sound control, and general design considerations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
68.
69.
In Ti-6-2-4-6 alloys, beta transforms to orthorhombic martensite when quenched from a temperature of 1188 or above, X-ray analysis showed that aging at 773 or 873 gradually reduces the degree of orthorhombicity until a hexagonal structure equivalent to alpha, but having the morphological characteristics of the prior martensite, is produced. The orthorhombicity is reduced by solute rejection to beta which forms as particles both homogeneously and heterogeneously within the martensitic structure. The structure at maximum hardness is a fine distribution of Burger’s oriented beta particles in a matrix of martensite of greatly reduced orthorhombicity. Overaging appears to occur as a result of coarsening of the homogeneous beta particles. It is shown that aging at temperatures from 873 to 1083 K results in growth of one particular varient of the beta which is located at the interface between twin related regions composing a martensite lath. This beta along with similarly oriented beta at lath interfaces forms a continuous beta matrix by a gradual growth process. It is shown that this matrix has the identical orientation and shape of the original beta grain prior to quenching. A mechanism is proposed to account for this “memory effect”.  相似文献   
70.
Antioxidant additives in polyethylene films have been shown to diffuse to the surface where they are subsequently lost, exposing the polymer to oxidation. Compatibility of antioxidants with polyethylene may be increased by use of silane coupling agents. In this study, three approaches to antioxidant modification are examined: (1) bonding antioxidant directly to silicon, (2) coupling the silane to an antioxidant hydroxyl function, and (3) dissolving antioxidants in silanes. All three approaches are shown to be effective in reducing antioxidant loss by diffusion.  相似文献   
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