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161.
Indigenous vegetables play an important role in Kenyan food security, but production is limited by poor seed quality. Traditionally, seeds have been traded through informal networks, but a new formal seed sector is emerging. This study assessed the relative potential for formal or informal seed systems to meet the need for high-quality indigenous vegetable seed. By evaluating determinants of farmers’ seed purchasing behaviour, we conclude that informal seed systems have greater potential to meet this need and should be strengthened. This study suggests that policy-makers should use context-specific data to guide decisions on seed policy.  相似文献   
162.
In an effort to increase both adolescents’ engagement with school and academic achievement, school districts across the United States have created small high schools. However, despite the widespread adoption of size reduction reforms, relatively little is known about the relationship between size, engagement and outcomes in high school. In response, this article employs a composite measure of engagement that combines organizational, sociological, and psychological theories. We use this composite measure with the most recent nationally-representative dataset of tenth graders, Educational Longitudinal Study: 2002, (N = 10,946, 46% female) to better assess a generalizable relationship among school engagement, mathematics achievement and school size with specific focus on cohort size. Findings confirm these measures to be highly related to student engagement. Furthermore, results derived from multilevel regression analysis indicate that, as with school size, moderately sized cohorts or grade-level groups provide the greatest engagement advantage for all students and that there are potentially harmful changes when cohorts grow beyond 400 students. However, it is important to note that each group size affects different students differently, eliminating the ability to prescribe an ideal cohort or school size.  相似文献   
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164.
The understanding of positive development across adolescence rests on having a valid and equivalent measure of this construct across the breadth of this period of life. Does the Positive Youth Development (PYD) construct based on the Five Cs model have satisfactory psychometric properties for such longitudinal measurement invariance? Using longitudinal data derived from the 4-H Study of PYD, we assessed 920 youth (61.6% female) from a racially and ethically diverse sample (67.3% European American) who participated in three waves (Grades 8–10) of data collection. Building on prior findings that the Five Cs (i.e., Competence, Confidence, Connection, Character, and Caring) model of PYD was a robust measure that could be assessed comparably during early adolescence, we tested a hierarchy of second-order confirmatory factor analysis models to assess the extent to which PYD can be measured equivalently across middle adolescence. Evidence was found for strict measurement invariance across three measurement occasions, including equivalence of first-order and second-order factor loadings, equality of intercepts of observed variables, and equality of item uniqueness and disturbances of the first-order factors. These results suggest that PYD can be measured in the same way across measurement occasions, a prerequisite for the study of development. Implications for research and application of being able to measure PYD equivalently across adolescence are discussed.  相似文献   
165.
Research on the mechanisms by which interparental conflict (IPC) affects child depression suggests that both parenting and children’s conflict appraisals play important roles, but few studies have explored the role of general cognitive style or included both parenting and cognitions in the same design. Moreover, the effects of IPC on minority children are not well understood. In this longitudinal study, parenting was examined as a mediator of the relation between increasing IPC and change in depression. General cognitive style was included as a moderator. The combined influence of parenting and cognitions was also explored. A racially and ethnically diverse sample of 88 fifth and sixth graders from two urban schools reported their cognitive style, depressive symptoms, and perceptions of conflict and parenting at two time points separated by one year. Parental warmth/rejection mediated the relation between IPC and depression, and general cognitive style acted as a moderator. Parenting, cognitive style, and IPC did not significantly interact to predict change in depression over time. Findings indicate that both parenting and children’s general cognitive style play a role in understanding the impact of increasing IPC on children’s well-being.  相似文献   
166.
This paper examines the federal government's success in implementing and providing high-quality service through e-government, something that has received very little attention. We define quality from the perspective of the end users of federal agency Web sites, as measured through customer survey data. Using data from the American Customer Satisfaction Index, we compare the performance of federal agency Web sites across a range of relevant variables with a private sector equivalent, e-business Web sites. Our findings suggest that federal e-government Web sites are not yet, in the aggregate, providing the same level of quality as their e-business counterparts. We also find significant variability among federal agencies. We discuss the implications of these findings for e-government performance measurement, performance benchmarking, and the market-centered theories of administrative reform that are driving e-government and similar transformations of government practice.  相似文献   
167.
This article takes a state's eye view of trends towards a more centralised system of governance in Australia. It argues that while globalisation strengthens the roles of national governments it also provides less noticed public policy and management opportunities for sub-national governments. The article shows how state governments in Australia can use high-level policy proposals to reinforce their continuing relevance as key members of a federal system of government. It proposes that skilful deployment of policy ideas and analyses can enable the states to sustain alternative national agendas despite hostility or lack of interest by the federal government. In conclusion, the article examines the implications for federal-state relations under the Rudd government. It suggests that the elements for productive reform agendas are present but that bringing them together will require considerable effort.  相似文献   
168.
169.
The risk for depression increases as Hispanic youth acculturate to U.S. society. This association is stronger for Hispanic girls than boys. To better understand the influence of culture and family on depressive symptoms, we tested a process-oriented model of acculturation, cultural values, and family functioning. The data came from Project RED, which included 1,922 Hispanic students (53?% girls; 86?% were 14?years old; and 84?% were U.S. born) from Southern California. We used data from 9th to 11th grade to test the influence of acculturation-related experiences on depressive symptoms over time. Multi-group structural equation analysis suggested that both family conflict and cohesion were linked with depressive symptoms. Hispanic cultural values were associated with family cohesion and conflict but the strength and direction of these relationships varied across cultural values and gender. For girls and boys, familismo and respeto were associated with higher family cohesion and lower family conflict. Moreover, gender roles were linked with higher family cohesion in girls but not in boys. These results indicate that improving family functioning will be beneficial for boys' and girls' psychological well-being. This may be achieved by promoting familismo and respeto for boys and girls and by promoting traditional gender roles for girls.  相似文献   
170.
Journal of Youth and Adolescence - Adolescence tends to be characterized by a temporary peak in delinquent behavior, and friends in particular play a key role in the initiation and the development...  相似文献   
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