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Curtis M. Jolly Budry Bayard Richard T. Awuah Simon C. Fialor Johnathan T. Williams 《Journal of Socio》2009,38(2):280-287
This study uses a modified health belief model (HBM) within a socio-economic framework to evaluate the influence of awareness and knowledge on actions to reduce aflatoxin (AF) contamination in groundnuts (peanuts). Data were collected in 2002 through a self-administered questionnaire from a sample of 367 individuals. Socio-economic factors affecting perceptions, awareness, knowledge, and action were examined using structural equation modeling. The perceived benefits of good quality groundnuts and/or groundnut products were the most important determinants of awareness and knowledge of AF among agricultural and health professionals in Ghana. Awareness, in turn, had a significant causal effect on the professionals’ decisions to take actions to increase the level of awareness of AF in the society. Demographic factors, such as gender and level of education significantly influenced knowledge of AF and the perception of the benefits of good quality groundnut. Type of profession had a significant influence on awareness and perceived seriousness of the AF problem. Education was a significant determinant of awareness of AF in groundnuts. The study generates important information for policy decision making when considering resource allocation to reduce food contamination in developing economies. 相似文献
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Jacquelien van Stekelenburg Bert Klandermans Wilco W. van Dijk 《The Journal of social issues》2009,65(4):815-838
The emphasis in the social-psychological collective action literature is on why individuals take part in collective action; however, it does not elaborate on how different mobilizing contexts may appeal to distinct motivational dynamics to participate. The present study connects the microlevel of motivational dynamics of individual protesters with the mesolevel of social movement characteristics. To do so a field study was conducted. Protesters were surveyed in the act of protesting in two different demonstrations in two different town squares simultaneously organized by two social movements at exactly the same time against the same budget cuts proposed by the same government. But with one fundamental difference, the movements emphasized different aspects of the policies proposed by the government. This most similar systems design created a unique natural experiment, which enabled the authors to examine whether the motivational dynamics of individual protesters are moderated by the social movement context. Previous research suggested an instrumental path to collective action, and the authors added an ideology path. The authors expected and found that power-oriented collective action appeals to instrumental motives and efficacy and that value-oriented collective action appeals to ideological motives, and, finally, that efficacy mediates on instrumental motives and motivational strength, but only so in power-oriented action. 相似文献
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In a make-to-order environment, lead time and price can play a crucial role in determining the financial success of a firm. Their importance increases when demand is sensitive to the quoted lead time and price. A model is presented which uses the quoted lead time and price as a mechanism to determine the optimal demand level. The relationships between the model parameters and their impacts on the firm's profit is also analysed. In addition, the effect of the number of job requests, and the mean processing time are examined. Based on the results presented in this paper, there is clear indication that the firm's profit is sensitive to the inventory holding rate, and that the inventory holding cost component is redundant in the presence of a tardiness cost component. 相似文献
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James W. Dilley 《Journal of American college health : J of ACH》2013,61(2):60-64
Abstract Objective: To investigate the motivational factors and the barriers to physical activity (PA) in traditional college students (TS) and nontraditional college students (NTS) and determine if differences exist between these 2 groups. Participants: A total of 746 college students; 628 were TS (19.1 ± 1.2 years), and 118 were NTS (31.2 ± 8.6 years). Methods: In fall 2010, students voluntarily completed a demographic questionnaire, Barriers to Being Active Quiz, and Exercise Motivations Inventory–2 (EMI-2). Results: EMI-2 revealed that TS and NTS differed on 8 of the 14 motivational factors for exercise. There was a significant difference between TS and NTS for the following barriers: fear of injury (p = .001), lack of resources (p = .017), and lack of skill (p = .003). Conclusion: Based on these findings, interventions can be developed for the varied needs of a diverse student population as it pertains to PA participation. 相似文献
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This paper considers a class of densities formed by taking the product of nonnegative polynomials and normal densities. These densities provide a rich class of distributions that can be used in modelling when faced with non-normal characteristics such as skewness and multimodality. In this paper we address inferential and computational issues arising in the practical implementation of this parametric family in the context of the linear model. Exact results are recorded for the conditional analysis of location-scale models and an importance sampling algorithm is developed for the implementation of a conditional analysis for the general linear model when using polynomial-normal distributions for the error. 相似文献