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991.
This article reviews the literature on the psychological consequences of dieting. In particular, the authors examine the impact of dieting on mood, self-esteem, cognition, and eating behavior. The famous Keys study of starvation is discussed in relations to impaired concentration, food preoccupation, negative affect, and binge eating behavior. Overall, the literature indicates that dieting has a negative impact on psychological well-being. As a result, alternative nondieting approaches toward eating are presented and recommended to promote psychological health.  相似文献   
992.
Migration has been the single most dynamic factor in the otherwise dreary development scenario of Kerala during the last quarter of the last century. It has contributed more to poverty alleviation and reduction in unemployment in Kerala than any other factor. As a result of migration, the proportion of the population below the poverty line has declined by 12 per cent. The number of unemployed persons – estimated to be only about 13 lakhs in 1998 compared with 37 lakhs reported by the Kerala Employment Exchanges – has declined by over 30 per cent. Migration has caused nearly a million married women in Kerala to live away from their husbands. Most of these so‐called “Gulf wives” experienced extreme loneliness to begin with, and were burdened with added family responsibilities to which they had not been accustomed when their husbands were with them. But over a period, and with a helping hand from abroad over the ISD, most came out of their early gloom. Their gain in autonomy, status, management skills and experience in dealing with the world outside their homes were developed the hard way and would remain with them for the rest of their lives for the benefit of their families and society. In the long run, the transformation of these million women will have contributed more to the development of Kerala society than all the temporary euphoria created by remittances and modern gadgetry. Kerala is dependent on migration for employment, subsistence, housing, household amenities, institution building, and many other developmental activities. The danger is that migration could cease, as shown by the Kuwait war of 1993, and repercussions could be disastrous for the State. Understanding migration trends and instituting policies to maintain the flow of migration is more important today than at any time in the past. Kerala workers seem to be losing out in international competition for jobs in the Gulf market. Corrective policies are needed urgently to raise their competitive edge over workers in competing countries in South and South‐East Asia. Like any other industry, migration from Kerala needs periodic technological upgrading of workers. Otherwise, there is a danger that the State might lose the Gulf market permanently. The crux of the problem is Kerala workers' inability to compete with expatriates from other South and South‐East Asian countries. The solution lies in equipping workers with better general education and job training. This study suggests a twofold approach. In the short run, the need is to improve the job skills of prospective emigrant workers. This could be achieved through ad hoc training programmes focussed on the job market in Gulf countries. In the long run, the need is to restructure the educational system, taking into consideration the future demand of workers not only in Kerala but also in potential destination countries all over the world, including the US and other developed countries. Kerala emigrants need not always be construction workers in the Gulf countries; they could also be software engineers in developed countries.  相似文献   
993.
This study assesses whether the influences of attitude towards deviance, exposure to delinquent peers and parental supervision and encouragement on antisocial behavior are moderated by depressive symptoms. Two hundred and thirty eight African American adolescents ages 13–19 from three public housing developments participated in this study. Results indicate that approximately half of the youth did not engage in antisocial behaviors in the last year. Gender, depression, attitudes and peers were significant correlates of antisocial behavior. Parental supervision and encouragement, and age were not related to antisocial behavior. Interaction effects suggest that the relative influences of attitudes towards deviance and delinquent peers on antisocial behaviors depend upon gender and level of depression symptoms. Implications for social work practice and future research are discussed.  相似文献   
994.
THE ANIMAL TEXT:     
We studied the dominant messages about animals in television commercials and the ways these messages might be subject to alternative readings. Six primary themes captured the portrayal of animals in the advertisements: animals as loved ones (e.g., a member of a family), as symbols (representation of logos or ideas), as tools (using animals for human use or consumption), as allegories, as nuisances, and animals in nature. Many of the commercials had multiple themes, indicating the varied, multilayered messages about animals in advertising and the different value and use categories that humans assign to different nonhuman animal species, upholding the ideology of the U.S. political economy. Finally, most of the animal portrayals were not anthropomorphized; those that were given human characteristics were typically part of a multithemed message that portrayed animals as allegories. Many of the animal images reinforced human gender and racial boundaries. This research establishes the importance of incorporating the study of nonhuman animals in sociological theory and research, particularly the animal image in popular culture and its connection to the portrayal of other outgroups, such as women and racial minorities.  相似文献   
995.
996.
997.
The continued expansion and fragmentation of biological disciplines impede education, communication, and efficient advance of biological research. Reversing these trends may require a unification of theories and concepts from all levels of biological organization. One form of this unification is the statement of generalizations that apply to all living systems. We explore the philosophical foundations of general theories of living systems by analyzing conceptual frameworks as they apply to biology. This analysis examines the relation of empirical observation, theories, and conceptual frameworks within the context of an individual scientist's conceptual continuum. Also presented are a small set of translevel generalizations that articulate our conceptual framework of living systems in terms of organismic system organization, the environmental system-organismic system dyad, system capacity, and system incorporation. A set of procedural rules are stated which suggest minimum criteria for the evaluation of the explanatory adequacy of biological theories. The relation of this work to other similar analyses and syntheses of biological knowledge is discussed.  相似文献   
998.
In 1960 Levene suggested a potentially robust test of homogeneity of variance based on an ordinary least squares analysis of variance of the absolute values of mean-based residuals. Levene's test has since been shown to have inflated levels of significance when based on the F-distribution, and tests a hypothesis other than homogeneity of variance when treatments are unequally replicated, but the incorrect formulation is now standard output in several statistical packages. This paper develops a weighted least squares analysis of variance of the absolute values of both mean-based and median-based residuals. It shows how to adjust the residuals so that tests using the F -statistic focus on homogeneity of variance for both balanced and unbalanced designs. It shows how to modify the F -statistics currently produced by statistical packages so that the distribution of the resultant test statistic is closer to an F-distribution than is currently the case. The weighted least squares approach also produces component mean squares that are unbiased irrespective of which variable is used in Levene's test. To complete this aspect of the investigation the paper derives exact second-order moments of the component sums of squares used in the calculation of the mean-based test statistic. It shows that, for large samples, both ordinary and weighted least squares test statistics are equivalent; however they are over-dispersed compared to an F variable.  相似文献   
999.
Historically, U.S. regulators have derived cancer slope factors by using applied dose and tumor response data from a single key bioassay or by averaging the cancer slope factors of several key bioassays. Recent changes in U.S. Environmental Protection Agency (EPA) guidelines for cancer risk assessment have acknowledged the value of better use of mechanistic data and better dose–response characterization. However, agency guidelines may benefit from additional considerations presented in this paper. An exploratory study was conducted by using rat brain tumor data for acrylonitrile (AN) to investigate the use of physiologically based pharmacokinetic (PBPK) modeling along with pooling of dose–response data across routes of exposure as a means for improving carcinogen risk assessment methods. In this study, two contrasting assessments were conducted for AN-induced brain tumors in the rat on the basis of (1) the EPA's approach, the dose–response relationship was characterized by using administered dose/concentration for each of the key studies assessed individually; and (2) an analysis of the pooled data, the dose–response relationship was characterized by using PBPK-derived internal dose measures for a combined database of ten bioassays. The cancer potencies predicted for AN by the contrasting assessments are remarkably different (i.e., risk-specific doses differ by as much as two to four orders of magnitude), with the pooled data assessments yielding lower values. This result suggests that current carcinogen risk assessment practices overestimate AN cancer potency. This methodology should be equally applicable to other data-rich chemicals in identifying (1) a useful dose measure, (2) an appropriate dose–response model, (3) an acceptable point of departure, and (4) an appropriate method of extrapolation from the range of observation to the range of prediction when a chemical's mode of action remains uncertain.  相似文献   
1000.
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