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121.
Constraints in our use of communication materials are often socially and historically produced; to ask after the constraints as we teach or compose can help us understand how material choices in producing communications articulate to social practices we may not otherwise wish to reproduce. In this writing, I consider the constraints Gunther Kress often applied to “word” and “image,” questioning their temporal and spatial structures.  相似文献   
122.
The work on the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) poses many puzzling conundrums that touch on complicated and important theoretical and practical issues. None of these can be resolved in the DSM-IV, but the authors hope that the Task Force's decisions will be informed by thorough reviews of the currently available evidence and extensive input from all sectors of the mental health field. A. J. Frances et al provide an alphabetical guide to DSM-IV conundrums that they hope will stimulate comments, suggestions, and criticisms about the work of the Task Force. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
123.
This article reviews and updates major research findings on depressive disorders and gender relationships in the United States and abroad. It also considers some of the World Health Organization's assessment instruments that may clarify the relationship between depression and gender and its cross-cultural ramifications. With psychology converging across national boundaries and with gender being a variable in psychological research both nationally and internationally, gender and its relationship to depressive states is emerging as a focal point of interest and concern. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
124.
A simple high efficiency solar water purification system   总被引:1,自引:0,他引:1  
A new passive solar water pasteurization system based on density difference flow principles has been designed, built and tested. The system contains no valves and regulates flow based on the density difference between two columns of water. The new system eliminates boiling problems encountered in previous designs. Boiling is undesirable because it may contaminate treated water. The system with a total absorber area of 0.45 m2 has achieved a peak flow rate of 19.3 kg/h of treated water. Experiments with the prototype systems presented in this paper show that density driven systems are an attractive option to existing solar water pasteurization approaches.  相似文献   
125.
We address the optimal location problem for two different types of service, designated as type-A and type-B, where some users may obtain both types of service in multi-purpose trips. We consider three user groups: (i) users of only the type-A service; (ii) users of only the type-B service; and (iii) users of both services in a single trip. We seek to locate three types of facilities: (i) type-A; (ii) type-B; and (iii) joint facilities that offer both services. We formulate a p-median-based model that minimizes the total travel distance and use it to investigate the effect of multi-purpose trip-makers on optimal facility types and locations. Examples are used to show that services tend to cluster in joint facilities, even when the proportion of multi-purpose behavior is small.  相似文献   
126.
Methods for manufacturing a variety of shapes of enhanced heat transfer condenser tubing have been developed. 32 different tubes have been studied, in a vertical orientation, for their overall heat transfer and pressure drop characteristics. All experiments were conducted with atmospheric steam condensing on the outside of the tube and water in forced convective flow on the inside, the heated length of the tube being 45 ins. (114 cm). The results show that, on the condensing steam side, coefficients up to 6 times comparable smooth tube values were obtained, and on the forced convective side up to 212times. The results are linked to tube shape, and appropriate theoretical analyses are presented.  相似文献   
127.
Duplication of the straight sinus is often noted in the venous phase of carotid angiograms. Since this vascular anomaly is rarely described in the literature, the authors present its incidence in a series of 700 cases, and consider its embryological origins and clinical significance.  相似文献   
128.
Longitudinal psychosocial data were used to predict the transition from virginity to nonvirginity among 430 7th–9th graders, all of whom were virgins at the initial testing in 1970. By the most recent follow-up in 1979, 93% reported having had sexual intercourse. Variation in time of onset of initial intercourse was categorized into 6 time periods and served as the main criterion variable in the study. Bivariate and multivariate analyses showed that antecedent measures of personality, the perceived environment, and behavior were predictive of variation in time of onset and, taken together, accounted for approximately 30% of the criterion variance. Results support the utility of the problem-behavior-theory framework and show onset of sexual intercourse to be a systematic aspect of psychosocial development in adolescence. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
129.
Chicken semen undiluted, diluted with a diluent containing fructose and/or mixed with turkey semen was used to inseminate Leghorn hens. In two of three experiments there was an improvement in fertility from insemination by mixed semen as compared to semen diluted to the same extent with the diluent.  相似文献   
130.
Presents an obituary for Clarence J. Leuba. Leuba spent a large part of his career (from 1930 to 1962) as chair of the Department of Psychology at Antioch College. At Antioch he was a pioneer in student counseling and in new teaching methods. Feeling that the lecture method was inadequate, he established small student-led discussion groups that could be monitored directly by the professor who was close at hand to offer aid or advice without being intrusive. He was a prolific writer, authoring numerous articles, chapters in others' books, and his own books, and was active in numerous professional organizations. In terms of Leuba's lifework, his principal contribution to psychology was his emphasis on the integration of the many aspects of the field that were developing in his lifetime and that were, too often in his view, not on speaking terms with each other. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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