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421.
When children are removed from their families because of maltreatment, the child welfare system seeks reunification whenever possible. Despite the importance of this goal, little is known about families who are able to achieve and maintain successful reunification. This qualitative study conducted in‐depth interviews with 15 families who completed their child welfare case plans, were reunited with their children and remained together for at least 1 year post‐reunification. Narrative analysis using a combination of thematic and structural coding was completed to examine the strengths and process families discussed related to their successful child welfare outcomes. This paper discusses one of those strengths, spirituality, in greater depth. Specifically, 12 participants situated the strength of spirituality within their stories as an important narrative element they perceived as critical, leading to important changes. Findings highlight the benefits some families receive from their spiritual beliefs, practices and faith communities when working towards reunification, suggesting child welfare practitioners be prepared to identify and honour this family strength. 相似文献
422.
Youssef Azghari Erna Hooghiemstra Fons J. R. van de Vijver 《Journal of Muslim Minority Affairs》2015,35(2):280-295
AbstractWe examined to what extent Moroccan-Dutch (N?=?25) between 15 and 32 years of age are oriented towards the Dutch and Moroccan community when describing their identities. We used the Twenty Statements Test (developed by Kuhn and McPartland (1954). See, M. H. Kuhn and T. S. McPartland, “An Empirical Investigation of Self-attitudes”, American Sociological Review, Vol. 19, No. 1, 1954, p. 69. In this study, participants were asked to complete the sentence with ‘I am..’ 20 times to assess how they described themselves.) and in-depth interviews to understand their challenges on the acculturation path since many face disadvantage and exclusion in the Dutch community. Moroccan-Dutch were, compared to the reference groups of mainstream Dutch (N?=?20) and Moroccans (N?=?25), more proud of their ethnic identity and attached to Islam. Though their Dutch language was dominant, they felt more Moroccan. They praised the Dutch openness, but suffered from negative stereotyping. Their participation in the Dutch community was low. To enhance their position, social professionals working with Moroccan-Dutch could draw on the rich ethnic and faith traditions of this group to encourage their deeper engagement with the Dutch society. 相似文献
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Nolan A. Wages Alexia Iasonos John O'Quigley Mark R. Conaway 《Pharmaceutical statistics》2020,19(2):137-144
This paper studies the notion of coherence in interval‐based dose‐finding methods. An incoherent decision is either (a) a recommendation to escalate the dose following an observed dose‐limiting toxicity or (b) a recommendation to deescalate the dose following a non–dose‐limiting toxicity. In a simulated example, we illustrate that the Bayesian optimal interval method and the Keyboard method are not coherent. We generated dose‐limiting toxicity outcomes under an assumed set of true probabilities for a trial of n=36 patients in cohorts of size 1, and we counted the number of incoherent dosing decisions that were made throughout this simulated trial. Each of the methods studied resulted in 13/36 (36%) incoherent decisions in the simulated trial. Additionally, for two different target dose‐limiting toxicity rates, 20% and 30%, and a sample size of n=30 patients, we randomly generated 100 dose‐toxicity curves and tabulated the number of incoherent decisions made by each method in 1000 simulated trials under each curve. For each method studied, the probability of incurring at least one incoherent decision during the conduct of a single trial is greater than 75%. Coherency is an important principle in the conduct of dose‐finding trials. Interval‐based methods violate this principle for cohorts of size 1 and require additional modifications to overcome this shortcoming. Researchers need to take a closer look at the dose assignment behavior of interval‐based methods when using them to plan dose‐finding studies. 相似文献
426.
Tree algorithms are a well-known class of random access algorithms with a provable maximum stable throughput under the infinite population model (as opposed to ALOHA or the binary exponential backoff algorithm). In this article, we propose a tree algorithm for opportunistic spectrum usage in cognitive radio networks. A channel in such a network is shared among so-called primary and secondary users, where the secondary users are allowed to use the channel only if there is no primary user activity. The tree algorithm designed in this article can be used by the secondary users to share the channel capacity left by the primary users.
We analyze the maximum stable throughput and mean packet delay of the secondary users by developing a tree structured Quasi-Birth Death Markov chain under the assumption that the primary user activity can be modeled by means of a finite state Markov chain and that packets lengths follow a discrete phase-type distribution.
Numerical experiments provide insight on the effect of various system parameters and indicate that the proposed algorithm is able to make good use of the bandwidth left by the primary users. 相似文献
427.
Shaun R. Seaman Daniel Farewell Ian R. White 《Scandinavian Journal of Statistics》2016,43(4):996-1018
Linear increments (LI) are used to analyse repeated outcome data with missing values. Previously, two LI methods have been proposed, one allowing non‐monotone missingness but not independent measurement error and one allowing independent measurement error but only monotone missingness. In both, it was suggested that the expected increment could depend on current outcome. We show that LI can allow non‐monotone missingness and either independent measurement error of unknown variance or dependence of expected increment on current outcome but not both. A popular alternative to LI is a multivariate normal model ignoring the missingness pattern. This gives consistent estimation when data are normally distributed and missing at random (MAR). We clarify the relation between MAR and the assumptions of LI and show that for continuous outcomes multivariate normal estimators are also consistent under (non‐MAR and non‐normal) assumptions not much stronger than those of LI. Moreover, when missingness is non‐monotone, they are typically more efficient. 相似文献
428.
This article investigates the choice of working covariance structures in the analysis of spatially correlated observations motivated by cardiac imaging data. Through Monte Carlo simulations, we found that the choice of covariance structure affects the efficiency of the estimator and power of the test. Choosing the popular unstructured working covariance structure results in an over-inflated Type I error possibly due to a sample size not large enough relative to the number of parameters being estimated. With regard to model fit indices, Bayesian Information Criterion outperforms Akaike Information Criterion in choosing the correct covariance structure used to generate data. 相似文献
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Rapid changes in China over the past two decades have led to significant problems associated with population migration and changing social attitudes, including a growing sex industry and concurrent increases in STIs and HIV. This article reports results of an exploratory study of microbicide acceptability and readiness and current HIV prevention efforts among female sex workers in two rural and one urban town in Hainan and Guangxi Provinces in southern China. The study focused on these women's knowledge and cultural understandings of options for protecting themselves from exposure to STIs and HIV, and the potential viability and acceptability of woman-initiated prevention methods. We report on ethnographic elicitation interviews conducted with women working within informal sex-work establishments (hotels, massage and beauty parlors, roadside restaurants, boarding houses). We discuss implications of these findings for further promotion of woman-initiated prevention methods such as microbicides and female condoms among female sex workers in China. 相似文献