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The phenomenon of switching addictions, defined as a substitution of one chemical or behavioral addiction pattern for another, has been observed in clinical practices for some time. This case study describes a patient who, in attaining abstinence from alcohol and other drug dependence, became a pathological gambler. The complexities of personal history, medical history and psychiatric history are described as well problems in treatment.  相似文献   
293.
    
Research concerning diversification and specialization of venture capital funds typically does not consider how a VC's effort might influence performance of different portfolios. We develop a model that analyzes VC effort when there is the potential for cross‐sectional and/or serial knowledge spillover among projects. The model generates two implications concerning VC effort and performance. First, VC post‐investment effort is a nonmonotonic function of performance shocks, especially for diversified VCs. Second, greater cross‐sectional and serial knowledge spillovers improve the performance of specialization relative to diversification, and shape how the number of decision stages in a project affects portfolio choice. Copyright © 2011 Strategic Management Society.  相似文献   
294.
    
We investigate here small sample properties of approximate F-tests about fixed effects parameters in nonlinear mixed models. For estimation of population fixed effects parameters as well as variance components, we apply the two-stage approach. This method is useful and popular when the number of observations per sampling unit is large enough. The approximate F-test is constructed based on large-sample approximation to the distribution of nonlinear least-squares estimates of subject-specific parameters. We recommend a modified test statistic that takes into consideration approximation to the large-sample Fisher information matrix (See [Volaufova J, Burton JH. Note on hypothesis testing in mixed models. Oral presentation at: LINSTAT 2012/21st IWMS; 2012; Bedlewo, Poland]). Our main focus is on comparing finite sample properties of broadly used approximate tests (Wald test and likelihood ratio test) and the modified F-test under the null hypothesis, especially accuracy of p-values (See [Volaufova J, LaMotte L. Comparison of approximate tests of fixed effects in linear repeated measures design models with covariates. Tatra Mountains. 2008;39:17–25]). For that purpose two extensive simulation studies are conducted based on pharmacokinetic models (See [Hartford A, Davidian M. Consequences of misspecifying assumptions in nonlinear mixed effects models. Comput Stat and Data Anal. 2000;34:139–164; Pinheiro J, Bates D. Approximations to the log-likelihood function in the non-linear mixed-effects model. J Comput Graph Stat. 1995;4(1):12–35]).  相似文献   
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The burgeoning literature on the climate change–human health nexus has focused almost exclusively on the health impacts of climate change with little attention to how ill-health and disease influence public perception of the health risks of climate change. Based on a cross-sectional survey of 1,253 individuals, linear regression was used to examine the independent effects of malaria and cholera prevalence, and neglected tropical disease comorbidities on perceived health risks of climate change. Individuals who reported more comorbidities had higher scores on perceived health risks of climate change compared with those who did not report any comorbidities. Unexpectedly, at the multivariate level, there were no statistically significant relationships between age of respondents, gender, and educational attainment on the one hand, and perceived health risks of climate change on the other hand. Individuals who were diagnosed with cholera in the past 12 months had higher scores on perceived health risks of climate change but there was no relationship between diagnosis with malaria in the past 12 months and perceived health risks. Individuals who had attained secondary education had lower scores on perceived health risks of climate change compared with those without any formal education. Given that this relationship did not exist at the bivariate level, it indicates that biosocial and sociocultural factors suppressed the relationship between secondary education attainment and perceived health risks of climate change. The findings underscore the complex relationship between perceived health risks of climate change and infectious disease, comorbidities, compositional, and contextual factors at the multivariate level.  相似文献   
297.
    
Using data from age 3 of the Fragile Families and Child Wellbeing Study, the current study explores the complex relationships between U.S. childcare subsidies and neglect. Specifically, the study examines two research questions: (i) Are U.S. childcare subsidies associated with self‐reported neglect among low‐income mothers? (ii) What individual types of self‐reported neglect are significantly reduced by receipt of childcare subsidy? Using negative binomial regression examining the relationships among mothers who were income‐eligible for childcare subsidy, we found that childcare subsidy was associated with lower levels of supervisory neglect, indicating an important role of subsidy in the lives of low‐income families.  相似文献   
298.
The EU’s offer of tariff‐ and quota‐free access for all exports from the Least Developed Countries (for Everything but Arms) has been welcomed as part of the WTO‐led initiative to assist these countries. But it is not without problems. As the Least Developed compete more with other developing countries than with the EU, trade is likely to be diverted from other, sometimes poorer, countries. (‘Least Developed’ is an official classification, not a neutral measure of poverty.) EBA contradicts and impedes the EU’s policies of reciprocity and promotion of regions: it not only creates an alternative trade regime, but seems unilaterally to break existing agreements. The article concludes that the policy was adopted for essentially political, not developmental, motives.  相似文献   
299.
Employment is crucial to the economic well-being of families. Using a multi-state sample of 412 rural low-income mothers, our study identifies factors influencing two employment decisions they make: labor force entry and number of hours supplied. A logistic regression model correctly predicted 80% of mothers’ work participation decisions. Employed mothers were older, better educated, and less likely to suffer from depression; as well as, more likely to have a driver’s license and receive child care assistance and the Earned Income Tax Credit. An estimated labor supply function explained 33% of the variation in hours worked by the 208 employed rural mothers. Higher wages, availability of health insurance, and overtime benefits predicted the number of hours they were willing to work.
Sharon B. SeilingEmail:
  相似文献   
300.
Conceptual frameworks that theorize relationship based work, caring and provisioning, are considered. It is argued that provisioning has greater potential for revealing the various dimensions of older women's contributions to society and citizenship claims. Data on the work and responsibilities of older women are presented. Participants belong to a group promoting public discussion on issues of security and justice for older women. This group was one of six research sites documenting the provisioning work done by women in diverse social locations. Findings reveal that older women carry large and complex provisioning responsibilities. This work is summarized under two categories: provisioning activities and provisioning strategies. Discussion of the findings focuses on three major issues facing older women: the unexpected magnitude of provisioning work they are doing; how to integrate the realities of an aging body into provisioning expectations; setting priorities when time is a scarce resource. Implications for theory and the citizenship claims of older women are considered.  相似文献   
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