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The following is an edited version of the proceedings of a symposium sponsored by the Middle East Policy Council on May 26, 1994, in the Hart Senate Office Building in Washington, DC. Former Senator George McGovern, President of the Council, introduced the panel; Thomas R. Mattair, the Councis Director of Research and Policy Analysis, was the organizer and moderator; Michael Collins Dunn, Senior Analyst of The International Estimate, Inc., and editor of its biweekly newsletter, The Estimate, was the discussant.  相似文献   
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The purpose of this study was to test hypotheses regarding (1) relations among negative affect and hormones of gonadal and adrenal origin in young adolescents, at three times of measurement, over a one-year period; and (2) stability of negative affect. The sample consisted of 10- to 14-year-old boys (N=56) and 9- to 14-year-old girls (N=52). The adolescents were assessed three times at 6-month intervals over one year. Serum levels of gonadotropins, gonadal steroids, adrenal androgens, and cortisol were assessed, as well as stage of pubertal development (Tanner criteria). The negative affect assessments consisted of self-report questionnaire and interview measures of anxiety and depressive affect, as well as mother reports of internalizing behavior problems. In the concurrent (cross-sectional) analyses, boys reporting higher levels of negative affect tended to be those at higher genital stage or older age, with lower testosterone and cortisol levels and lower dehydroepian-drosterone sulphate levels. In the longitudinal analyses, negative affect, and to a lesser extent hormone levels at the first time of measurement predicted negative affect 12 months later. The findings suggest that puberty-related hormone levels should be considered along with psychological characteristics in examining the processes involved in the development of negative affect during the pubertal years.Received Ph.D. from The Pennsylvania State University. Research interests include hormone-behavior interactions and emotional development.Received Ph.D. from The Pennsylvania State University. Research interests include neuroendocrinology and adolescent depression.Recieved M.D. from Athens University. Research interests include hypothalamic releasing factors and stress.  相似文献   
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Body image and weight loss beliefs and behaviors were assessed in 341 female and 221 male high school students. Estimates of body dissatisfaction varied depending on the measurement strategy used. Despite having similar weight distributions around the expected norm, girls were significantly more dissatisfied with their bodies than boys. Body Mass Index was positively related to body dissatisfaction in girls and boys, while higher exercise levels were related to higher body satisfaction in boys. Nearly two-thirds of girls and boys believed being thinner would have an impact on their lives, but the majority of girls believed this would be positive while the majority of boys believed this would be negative. Thirteen percent of female subjects reported using one or more extreme weight loss behavior at least weekly. Beliefs regarding the effectiveness of different weight loss measures were assessed. Weight loss behaviors in this Australian sample appear similar to comparable U.S. samples.Received Ph.D. from University of Tasmania. Main research interest in body image, weight loss behaviors, and eating disorders.Received Ph.D. from University of Connecticut. Main research interest in body image, eating disorders and weight loss behaviors.Dietitian degree from Melbourne University, Melbourne. Main research interest in eating practices and clinical outcome.M.D. from University of Melbourne, D.P.M. from U.K. FRC Psych. Main research interests in eating disorders.B.B.Sc.(Hons.) received from La Trobe University, Melbourne, B.A. received from University of Minnesota, Duluth. Main research interest in attitudes and attributions.B.A. Received from University of Minnesota, Duluth. Main research interest in adolescence and eating disorders.  相似文献   
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Although there has been evidence for some time of a sex difference in depression, relatively little research has examined the developmental process by which women come to be at greater risk than men for depression. In this paper, the developmental pattern of depressed affect is examined over early and middle adolescence, with a special focus on the patterns of boys as compared to girls. In addition, a developmental model for mental health in adolescence is tested for its power in explaining the emergence of gender differences in depression. Longitudinal data on 335 adolescents randomly selected from two school districts were used to test the hypotheses. Results revealed that girls are at risk for developing depressed affect by 12th grade because they experienced more challenges in early adolescence than did boys. The sex difference in depressed affect at 12th grade disappears once early adolescent challenges are considered.This research was supported in part by grants MH30252/38142 to A. Petersen. We gratefully acknowledge the contributions of study participants and staff. Portions of this material were presented in a symposium at the 1988 meeting of the Society for Research on Adolescence, and one at the 1989 meeting of the Society for Research in Child Development.Received Ph.D. from University of Chicago in 1973. Research interest in biopsychosocial development in adolescence, with a focus on sex differences in mental health.Research interests include adolescent mental health, and parent and peer relationships.Received Ph.D. in psychology from The Pennsylvania State University. Research interests include development of affective and conduct disorders, especially sex differences in these problems.  相似文献   
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Conclusions To what extent do the transactions costs of implementing alternative instruments for pollution control affect the choice of the optimal instrument and the efficient intensity of control under that instrument? In a comparison of Least-Cost Regulatory Standards and Revenue-Neutral Pigouvian Taxes, it is the higher transactions costs of implementing the taxes that make Pigouvian Taxes the more costly of the two instruments. However, a more practical comparison of instruments is between Politically Feasible Standards, Marketable Discharge Permits, and Revenue-Raising Pigouvian Taxes. Here, the relationship between the transactions costs of implementation and total pollution costs are in an almost linear inverse relationship. The lower the pollution costs associated with a particular instrument, and therefore the more desirable the instrument, the higher the transactions costs of implementation. Other factors such as political distortion and welfare gains prove to be more important than the transactions costs of implementation.Assuming that variable transactions costs decrease with the optimal level of pollution for regulatory standards but increase with the optimal level for market oriented instruments, an accounting of transactions costs results in less stringent control in the case of regulatory standards and more stringent control in the case of market oriented instruments. However, the percentage effect is very small. Moreover, it is smaller in both cases if marginal pollution damage rises with the level of pollution, as it is usually presumed to do, rather than remain constant as assumed in this paper for purposes of aggregation. A major conclusion of this paper is that Pigouvian Taxes are the superior instrument for pollution control when the raising of public revenues is a desired objective. However, the various conclusions of this paper should be viewed as tentative because the data on which they are based are no longer current. Moreover, the critical estimates of transactions costs are somewhat dubious. It is hoped that new data will be collected for answering the questions raised in this paper. When this is done, a more powerful approach, one that obviates the need for the artificial, one-dollar-damaging, aggregate pollutant, would be an expanded linear programming model in which the transactions costs are treated as separate coefficients of the individual pollution control methods. Separate sets of such coefficients, each corresponding to a different policy instrument such as Least-Cost Regulatory Standards, Revenue-Neutral Pigouvian Taxes, etc., would enable the investigator to directly derive solutions that specify the optimal policy instrument as well as the optimal set of pollution control method activity levels.I am grateful to William Ascher, Murray Weidenbaum, and two anonymous referees for helpful guidance on the paper.  相似文献   
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To date, there has been little persuasive validation of Elazar'sconcept of political subcultures as it applies to mass publics.This study represents an attempt to establish an agenda forfuture research utilizing this popular formulation of the relationshipbetween the citizen and government. A statewide sample of 805residents of Illinois was given agree-disagree statements representingElazar's individualistic, moralistic, and traditionalistic subcultures.The data are used to explore three basic research questions:Do individuals discriminate themselves along the political subculturedimensions suggested by Elazar? Can region of residence, religion,or ethnicity be used as surrogates for individual level politicalculture? And, can political culture, measured directly at theindividual level, add significant independent explanation ofpolitical behavior and opinions beyond that of socioeconomiccharacteristics?  相似文献   
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