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131.
In Exp I, stable lines of mice that differed in the frequency and latency of attacks were rapidly established in 2 series (by S? in the 1st series and S? or S? in the 2nd). For evaluation of the developmental-genetic proposal, an analysis was made of the ontogeny of aggressive expression in male mice of the 2 series, with a report provided of the S? and S? generations of the 2nd breeding series (Exps II and III). Comparisons between results of a longitudinal design and results of a new type of cross-sectional design (involving only siblings, or co-sibial) indicated (a) a reliable developmental course of attack expression, with a sharp rise in early maturity and a slow decline thereafter; (b) a convergence in later maturity of the behavior of lines selectively bred for high or low aggressive behavior, if Ss had been assigned to the longitudinal design; (c) a strong effect of repeated testing on attack latency and frequency, even though the dyadic tests were brief in duration and separated by long intervals. In addition, cross-generational comparisons suggested that the selective breeding differences came about primarily by changes in the behavior of the low aggressive lines, in that these Ss failed to show in early maturity the sharp increases in attack occurrence that were observed in earlier generations. Implications for developmental and evolutionary concepts (e.g., neoteny, acceleration, and heterochrony) are discussed. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
132.

Background  

The health benefits of soy isoflavones have been widely investigated; however, there are some concerns as to whether soy isoflavones, similar to ipriflavone, a synthetic isoflavone, cause lymphocytopenia in postmenopausal women. Hence, the purpose of this study was to investigate the extent to which 12-month supplementation of 25 g soy protein containing 60 mg isoflavones alters lymphocyte counts or other hematological parameters in postmenopausal women who were not on hormone replacement therapy.  相似文献   
133.
Presents a systems-oriented approach to the leadership development of top-level executives. A structured program is described that is designed to have a positive impact at the organizational level through focused work with the individual client. Leadership effectiveness is seen as strongly influenced by the individual's past, personal life, and work environment. Comprehensive information gathered from the client's work life and personal life increases understanding of behaviors that influence performance, and thereby fosters change. Development is perceived from a holistic point of view, with benefits to the organization accruing through increased effectiveness in any areas of the client's life. A case example (of a 40-yr-old male) is given to illustrate how this approach is put into effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
134.
Examines the value of a nonstructured, expressive approach (NEA) to group therapy with older adults, which stemmed from the authors' work with outpatients (aged 62–89 yrs). Experience during 10 mo with the NEA group revealed expected as well as unexpected group dynamics and issues. Therapists should recognize older individuals' abilities to define their own perspective on the phase of life through which they are passing, even when these definitions are contrary to technique- or theory-based expectations. The NEA stresses the importance of maintaining flexibility to identify normal and desirable coping mechanisms, defenses, and age-related personality changes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
135.
Measured counselor attitudes regarding women 3 times over a span of 6 yrs in Minnesota to chart attitude changes that have accompanied increasing career development interests on the part of women. An 18-item survey was constructed to tap 3 dimensions of attitude, including attitudes regarding the dual role of mother and worker, perceptions of sex role definition, and expectations regarding the societal impact of women. Changes from 1968 through 1971 to 1974 (139, 143, and 179 responses in 1968, 1971, and 1974, respectively) suggest more acceptance of the dual role and broader sex role definitions. Differential attitude changes based on sex and age of counselor are examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
136.
Solutions to the two-dimensional, rectangular orthogonal packing problem rarely guarantee optimality, as exact algorithms require a prohibitive amount of computing time. A means of calculating the maximum number of boxes which can be fitted would be useful, both as a measure of optimality, and as an aspiration level. Existing estimates are accurate for approximately 15% of problems typically encountered in pallet loading applications. This paper discusses a technique for reducing the loading area before applying these estimates and shows that their effectiveness can be increased to provide an exact solution for over 70% of a random data sample.  相似文献   
137.
Investigated how individuals use information about a target student's past academic performance to evaluate that performance and to predict future performance. 12 linear and nonlinear performance sequences, each ostensibly representing the performance of a different 1st-, 6th-, or 12th-grade student, were judged by 70 undergraduates. Results indicate that although the target's final performance was an important determinant of Ss' responses, a simple recency model did not adequately account for the data. In addition, differences emerged between Ss' evaluations of the target's past performance and predictions of the target's future performance. Contrary to expectations, the target's grade level did not significantly influence evaluations or predictions. The importance of observers' reactions to nonlinear as well as linear performance patterns is discussed in the context of clarifying teacher expectancy effects. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
138.
Ultrasonic cavitation was employed to enhance sensitivity of bacterial spore immunoassay detection, specifically, enzyme-linked immunosorbent assay (ELISA) and resonant mirror (RM) sensing. Bacillus spore suspensions were exposed to high-power ultrasound in a tubular sonicator operated at 267 kHz in both batch and flow modes. The sonicator was designed to deliver high output power and is in a form that can be cooled efficiently to avoid thermal denaturation of antigen. The 30-s batch and cooled flow (0.3 mL/min) sonication achieved an approximately 20-fold increase in ELISA sensitivity compared to unsonicated spores by ELISA. RM sensing of sonicated spores achieved detection sensitivity of approximately 10(6) spores/mL, whereas unsonicated spores were undetectable at the highest concentration tested. Improvements in detection were associated with antigen released from the spores. Equilibrium temperature increase in the tubular sonicator was limited to 14 K after 30 min and was maintained for 6 h with cooling and flow (0.3 mL/min). The work described here demonstrates the utility of the tubular sonicator for the improvement in the sensitivity of the detection of spores and its suitability as an in-line component of a rapid detection system.  相似文献   
139.
Characteristics of impala (Aepyceros melampus) skeletal muscles   总被引:1,自引:0,他引:1  
The aim of this study was to determine citrate synthase (CS), phosphofructokinase (PFK) activities and myosin heavy chain (MHC) isoform contents in four muscle groups (semimembranosus (S), deltoideus (D), longissimus lumborum (LL), and psoas major (PM)) of impala (n=6). All four muscle groups expressed predominantly MHC IIa (means of 55±22-93±12%). MHC IIx was only expressed in D. In D, positive correlations were found between MHC I and age (r=0.93; P<0.05) and the weight of the animals (r=0.94; P<0.01). PFK (means of 175±179-374±181), CS (means of 100±23-126±38 μmol/min/gdw) and MHC content indicated that energy provision in the impala is produced to a large extent via oxidative pathways and fibre types vary with animal characteristics.  相似文献   
140.
Examined relations of prosocial and antisocial classroom behavior to academic achievement, taking into account the possible mediating effects of academically oriented classroom behavior and teachers' preferences for students. Correlational findings based on 423 students in 6th and 7th grade indicated that prosocial and antisocial behavior are related significantly to GPA and standardized test scores and to teachers' preferences for students and academic behavior. Results from multiple-regression analyses suggested that both types of social behavior are significant, independent predictors of classroom grades, even when academically oriented behavior and teachers' preference for students, IQ, family structure, sex, ethnicity, and days absent from school are taken into account. Results of regressions suggested that significant correlations between social behavior and academic outcomes can be explained in part by significant relations between social and academic behavior. The role of social behavior in promoting classroom learning is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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