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211.
PCORnet, the National Patient-Centered Clinical Research Network, seeks to establish a robust national health data network for patient-centered comparative effectiveness research. This article reports the results of a PCORnet survey designed to identify the ethics and regulatory challenges anticipated in network implementation. A 12-item online survey was developed by leadership of the PCORnet Ethics and Regulatory Task Force; responses were collected from the 29 PCORnet networks. The most pressing ethics issues identified related to informed consent, patient engagement, privacy and confidentiality, and data sharing. High priority regulatory issues included IRB coordination, privacy and confidentiality, informed consent, and data sharing. Over 150 IRBs and five different approaches to managing multisite IRB review were identified within PCORnet. Further empirical and scholarly work, as well as practical and policy guidance, is essential if important initiatives that rely on comparative effectiveness research are to move forward. 相似文献
212.
Xinyun Wu Shengfeng Yan Xin Wan Zhipeng Lü 《Journal of Combinatorial Optimization》2016,32(2):445-468
The routing and wavelength assignment problem (RWA) has shown to be NP-hard if the wavelength continuity constraint and the objective of minimizing the number of wavelengths are considered. This paper introduces a multi-neighborhood based iterated tabu search algorithm (MN-ITS), which consists of three neighborhoods with a unified incremental evaluation method, to solve the min-RWA problem. The proposed MN-ITS algorithm is tested on a set of widely studied real world instances as well as a set of challenging random ones in the literature. Comparison with other reference algorithms shows that the MN-ITS algorithm is able to improve five best upper bounds obtained by other competitive reference algorithms in the literature. This paper also presents an analysis to show the significance of the unified incremental evaluation technique and the combination of multiple neighborhoods. 相似文献
213.
This paper studies how rising male incarceration and its impact on marriage markets has affected female incentives to gain weight. Exogenous variation in marriage market conditions is obtained from differential trends in male incarceration rates across markets defined by race, location and age. We provide evidence that marriage market conditions do in fact affect the incidence of obesity. In particular, we find that increases in male imprisonment that reduced the male–female sex-ratio explain about 18 % of the increase in the female obesity rate for African-Americans in the United States over the 1990s. Results are particularly large for those in the younger age group (ages 18–23). 相似文献
214.
Sweden is a welfare state with a family policy that strongly emphasizes equality without distinction by place of birth or gender. In this study, we investigate the differences in uptake of parental leave between native and immigrant mothers, and the connection to labour-market attachment. Sweden represents a unique case study, not only because of the strong effort to combine work and family for all women and men, the high level of fertility and the large presence of immigrants in the country; it also enables a detailed and sophisticated analysis based on the high-quality data derived from its population registers. We find that immigrant mothers use more parental leave benefit the first year after their child’s birth, but then fewer in the second year compared with native mothers. The differences diminish when labour-market activity is controlled for. Additionally, after a time in Sweden, immigrant mothers use leave more similarly to how native mothers do. 相似文献
215.
Research on subjective wellbeing includes studies of both domain-related and global distress. The mental health literature,
though, focuses almost exclusively on global distress. This seems to be partly due to a common belief that psychological distress,
and the moods that comprise distress, necessarily lack referential content. However, if that were the case it would make little
sense for any study to ever focus on domain-related distress. The research presented in this report clarifies the relation
between global and domain-related distress. We compare confirmatory factor analytic models of the joint relationship among
symptoms of global distress with affective symptoms of distress about work, home, and physical appearance. Data are from a
general population telephone survey. In the best-fitting models domain-related distress and global psychological distress
are related but distinct latent variables. We discuss the theoretical and methodological implications of the models, and model
choice. 相似文献
216.
This paper discusses a novel strategy for simulating rare events and an associated Monte Carlo estimation of tail probabilities.
Our method uses a system of interacting particles and exploits a Feynman-Kac representation of that system to analyze their
fluctuations. Our precise analysis of the variance of a standard multilevel splitting algorithm reveals an opportunity for
improvement. This leads to a novel method that relies on adaptive levels and produces, in the limit of an idealized version
of the algorithm, estimates with optimal variance. The motivation for this theoretical work comes from problems occurring
in watermarking and fingerprinting of digital contents, which represents a new field of applications of rare event simulation
techniques. Some numerical results show performance close to the idealized version of our technique for these practical applications. 相似文献
217.
A considerable literature documents the deleterious economic consequences of incarceration. However, little is known about the consequences of incarceration for household assets—a distinct indicator of economic well-being that may be especially valuable to the survival of low-income families—or about the spillover economic consequences of incarceration for families. In this article, we use longitudinal data from the Fragile Families and Child Wellbeing Study to examine how incarceration is associated with asset ownership among formerly incarcerated men and their romantic partners. Results, which pay careful attention to the social forces that select individuals into incarceration, show that incarceration is negatively associated with ownership of a bank account, vehicle, and home among men and that these consequences for asset ownership extend to the romantic partners of these men. These associations are concentrated among men who previously held assets. Results also show that post-incarceration changes in romantic relationships are an important pathway by which even short-term incarceration depletes assets. 相似文献
218.
Marcelo Marchesini da Costa 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2016,27(3):1064-1090
What are the local characteristics influencing where new nonprofits will be established? How important are community needs, available resources, or the existence of similar organizations for nonprofits’ location? This paper analyzes how the characteristics of 5562 Brazilian municipalities in the year 2000 help explain the location of nonprofits formed between 2001 and 2010. Based on geographically weighted regressions, results indicate that neither access to resources nor poor socioeconomic indicators are powerful influences on nonprofit location in Brazilian municipalities. The main predictor of nonprofit entry is a high pre-existing density of nonprofits in that area. These findings, however, vary across regions and nonprofit fields of activity. By mapping the effect of key explanatory variables, this paper helps understand nonprofit location. The methodology and findings on nonprofit location presented here are novel and may contribute to research in other countries. 相似文献
219.
Historically, child maltreatment has been seen as an issue warranting the involvement of the American government. However, over time, the definition of child maltreatment has changed; typically, maltreatment is often understood as a violation of the parental right to care for and protect a child. Consequently, the government, through systems such as child protective services is expected to be the acceptable parental alternative. As illustrated by the numerous negative outcomes experienced, it is clear that the system is not meeting the needs of abused and neglected children. This bureaucratic neglect is allowed to occur because of population primarily served by the child welfare system, the poor and families of color. In this way, dynamics of power and privilege manifest in the differing expectations of appropriate care between biological parents and the foster care system. 相似文献
220.