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991.
In pediatric chronic illness, little is known about the relational interactions between adolescent patients, parents, and illnesses and how they influence self-management of illness. We conducted interviews with 32 individuals (16 dyads) representing adolescents diagnosed with a chronic illness and their primary parent who had been referred to a psychosocial treatment program for challenges with illness management. Interviews were conducted individually and analyzed dyadically using grounded theory to better understand the relational processes that may be contributing to illness management difficulties. Results include a theory of patient–parent illness responses and how parental illness meanings play a role in adolescent self-management. Results can be used to better understand and treat family relational patterns that may be influencing pediatric illness management challenges.  相似文献   
992.
We examined how perceived acculturation expectations from parents and school, and ethnic discrimination predicted early adolescents’ heritage and mainstream acculturation orientations at home (private domain) and in school (public domain) one year later. We surveyed 263 early adolescents of immigrant background in Germany (Mage = 10.44 years, 60% female). Multigroup path analyses revealed that perceived acculturation expectations and ethnic discrimination were more strongly related to adolescents’ private than public acculturation orientations. Parental heritage expectations were the strongest predictor of adolescents’ acculturation orientations. Boys were more susceptible than girls to ethnic discrimination and acculturation expectations in school, which affected their private and public acculturation orientations. Results highlight the importance of integrating domain‐specific and gendered experiences when analyzing adolescents’ acculturative development.  相似文献   
993.
The present research examined how school contexts shape the extent to which beliefs about the potential for change (implicit theories) interact with social adversity to predict depressive symptoms. A preregistered multilevel regression analysis using data from 6,237 ninth‐grade adolescents in 25 U.S. high schools showed a three‐way interaction: Implicit theories moderated the associations between victimization and depressive symptoms only in schools with high levels of school‐level victimization, but not in schools with low victimization levels. In high‐victimization schools, adolescents who believed that people cannot change (an entity theory of personality) were more depressed when they were victimized more frequently. Thus, the mental health correlates of adolescents’ implicit theories depend on both personal experiences and the norms in the context.  相似文献   
994.
Urban Ecosystems - Critical resources for birds nesting in cities can support populations in spite of the challenges imposed by urbanization, and the identification of such resources can shed light...  相似文献   
995.
ABSTRACT

Students’ emotions during stays abroad have mainly been treated as ”culture shock”, where difficulties are interpreted as universal ”stages” towards ”adaptation”. This paper explores how students from different cultural and educational traditions experience studying abroad differently. The study presents a qualitative study of 18 Danish and Chinese students in Chinese and Danish universities and situates itself within the literature on culture shock, student emotions and study-abroad experiences. The study exposes the students’ complex emotions throughout their studies abroad and explains how these emotions relate to processes of self-formation, professional and academic development, increase or decrease in freedom, and student agency.  相似文献   
996.
997.
Population and Environment - We investigate the extent to which droughts impact migration responses of rural households in Thailand and Vietnam, as well as the role of underlying mechanisms such as...  相似文献   
998.
Noninferiority trials intend to show that a new treatment is ‘not worse'' than a standard-of-care active control and can be used as an alternative when it is likely to cause fewer side effects compared to the active control. In the case of time-to-event endpoints, existing methods of sample size calculation are done either assuming proportional hazards between the two study arms, or assuming exponentially distributed lifetimes. In scenarios where these assumptions are not true, there are few reliable methods for calculating the sample sizes for a time-to-event noninferiority trial. Additionally, the choice of the non-inferiority margin is obtained either from a meta-analysis of prior studies, or strongly justifiable ‘expert opinion'', or from a ‘well conducted'' definitive large-sample study. Thus, when historical data do not support the traditional assumptions, it would not be appropriate to use these methods to design a noninferiority trial. For such scenarios, an alternate method of sample size calculation based on the assumption of Proportional Time is proposed. This method utilizes the generalized gamma ratio distribution to perform the sample size calculations. A practical example is discussed, followed by insights on choice of the non-inferiority margin, and the indirect testing of superiority of treatment compared to placebo.KEYWORDS: Generalized gamma, noninferiority, non-proportional hazards, proportional time, relative time, sample size  相似文献   
999.
Product bundling has become increasingly prevalent not only in consumer goods but also in the industrial sector. We study a purchasing problem in which a buyer must obtain necessary numbers of various stock items from a variety of vendors who charge different prices, have limited capacities and different levels of quality, and offer bundled products at discounted prices. We examine relationships among different bundling scenarios and show that the most general scenario is one in which free items are given to the buyer when sufficient quantities are purchased. We develop a mixed integer linear program that finds the purchasing strategy for the buyer that minimizes the total purchase cost. We present computational results which indicate that the problem is very tractable to solve optimally on a personal computer with standard optimization software. Finally, three extensions of the model are discussed.  相似文献   
1000.
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