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761.
Abstract Numerous studies have demonstrated dwindling consumer confidence in the safety of the food supply and growing interest in purchasing "safe" foods. However, this research has painted no consistent picture of those concerned about food safety, nor has it investigated the relationship between environmental and food safety attitudes. A mail survey of Japanese and the United States consumers is used to evalulate whether selected environmental attitudes can explain food safety concerns and behavior. Findings indicate high concern about food safety in both countries, but income, age, education, and attitudes about the impacts of fossil fuel use explain little of the variance. Instead, that concern appears to be prompted largely by an interest in obtaining a healthy diet. It is also noted that Japanese consumers are more concerned about both food safety and the impacts of fossil fuel use, perhaps because of Japan's lack of natural resources and high food import levels. 相似文献
762.
Jack H. Watson Jr. 《Journal of American college health : J of ACH》2013,61(1):11-14
Abstract Because of the increasing prevalence of eating disorders in college populations, it is increasingly important for student health services to identify affected individuals. Therefore, the authors analyzed the student health forms of member schools of the New York State College Health Association for the presence of items that would identify an eating disorder. Directors of health services that include specific questions about eating disorders on health forms were then surveyed for their opinions about this practice. Specific items about eating disorders (anorexia nervosa, bulimia, vomiting to lose weight, laxative use to lose weight) were included on 5 of 111 forms. Less specific items including dissatisfaction with weight, being on a diet, or binge eating appeared on 10% of forms. Approximately one-third of the students known by health service staffs to have an eating disorder reported this on their health form, when provided a specific opportunity to do so. Even though underreporting by students is potentially a problem in such circumstances, the health service directors all recommended the inclusion of items relating to eating disorders on student health forms. “Human Papillomavirus Type 16 and Early Cervical Neoplasia,” CHRISTOPHER P. CRUM, et al. Flat warts (condylomata) of the uterine cervix are sometimes cytologically atypical and have abnormal mitotic figures; they are thought to be possible precursors of cancer of the cervix. Flat warts are caused by any of a number of types of human papillomaviruses (HPVs), one of which (HPV 16) has been previously associated with invasive cancer of the cervix. To determine whether HPV 16 is also associated with flat warts with abnormal mitoses, we analyzed 23 flat warts by DNA-hybridization techniques for the presence of HPV 16 and other HPV types, and correlated the results with the histology. Of 10 lesions with abnormal mitotic figures, 7 contained HPV 16, and 1 contained another type of HPV. Of 13 lesions without abnormal mitotic figures, only 1 contained HPV 16, and 7 contained other types of HPV. We conclude that the presence of HPV 16 correlates with the presence of abnormal mitotic figures in flat warts of the cervix, and that this type of flat wart is a precursor of invasive cancer of the cervix. (New England Journal of Medicine 1984;310:880–3.) 相似文献
763.
Raúl A. Muñoz Michael J. Pisani Thomas M. Fullerton Jr. 《The Social Science Journal》2011,48(4):612-620
This paper studies the exchange rates at which Mexican pesos are accepted for retail purchases in El Paso, Texas. A stratified random sample of 586 participating firms is surveyed to examine two aspects of reverse dollarization in the El Paso/Ciudad Juárez border region. The first is to determine the percentage of retail businesses in El Paso that accept foreign currency in the form of Mexican pesos. The results suggest that just over 13.1% (77/586) of all retail firms in this market accept pesos, which on average, comprise 4.35% of total sales for those firms. The second is to calculate the effective exchange rate at which firms accept Mexican pesos. We find that 68.5% of firms accepting the peso do so at a premium. We discern these two aspects further utilizing various multivariate analyses. 相似文献
765.
John W. Sawyer Jr. 《The American statistician》2013,67(4):300-308
A strategy is presented for producing code to evaluate first partial derivatives of a function f by computer. Advantage is taken of the capabilities that a compiler must have simply to bring about the evaluation of f. A bound kt on the time it should take to evaluate the partials of f is developed, where f takes time t to evaluate and k is independent of f. The benefits of the differentiation strategy for weighted least squares analysis of categorical data are discussed. 相似文献
766.
A substantial body of sociological research has examined the relationship between farmers’ environmental attitudes and their conservation behaviors, but little research has compared the attitudes of producers and consumers toward the environment with their behaviors or practices in support of sustainable agri-food systems. This paper addresses these shortcomings by analyzing the intersection between producer and consumer attitudes toward environmental sustainability with their actual practices, drawing data from focus group interviews and surveys with producers and consumers in Washington State, USA. We compare farmers’ attitudes toward several agricultural and environmental policies with their self-reported practices to examine whether support for environmental policies aligns with sustainable farming practices. For consumers, we investigate the relationship between their attitudes toward the same agricultural and environmental policy issues with their interest in purchasing food produced in an environmentally sustainable manner. Through our analyses, we find that consumers’ and producers’ practices are not always consistently correlated with their environmental attitudes, but that support for agricultural land preservation is one policy area in which the interests of producers and consumers intersect with their interest in sustainable farming and food. Findings from our individual and focus group interviews assist us in understanding the multiple, sometimes competing, factors that consumers and producers must weigh in making decisions about environmentally sustainable food and farming. 相似文献
767.
768.
Craig's theorem on the independence of quadratic forms in normal variates is traced from its first form, for iid standard normal variates, to the form for variates following an arbitrary nonsingular joint normal distribution. This article gives the main thrust of the development and makes recommendations on coverage of the theorem in courses and textbooks. The history of Craig's theorem is not a happy one. The authors of the earlier articles in the literature tended to make errors of a linear-algebraic nature. Authors of more recently published textbooks have given incorrect or misleadingly incomplete coverage of Craig's theorem and its proof. 相似文献
769.
770.
This paper examines the effect of climate on migration. We examine whether climate is an influential factor in internal migration. We assume that most persons tend to avoid exposure to bitter and cold winters, and excessively hot and humid summers, preferring climates between these extremes. When engaging in-migration decision-making, therefore, to the extent possible, considerations involving climate are believed to be brought into the calculus. There is a very limited demographic literature on the effects of climate on migration.In this paper, we undertake an aggregate-based analysis of the effect of climate on migration. We examine this relationship among the 50 states of the United States. We focus attention on the varying effects of climate on three migration measures for the 1995–2000 time period, namely, in-migration, out-migration, and net migration. We next evaluate the effect of climate on migration in the context of a broad application of human ecology. Here climate, a manifestation of the physical environment, is measured with three major independent variables. The other ecological predictors pertaining to organization, population, technology, and the social environment are used as controls. This enables us to examine the effects of climate on migration in the context of competing ecological hypotheses. 相似文献