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451.
Parental substance misuse is a significant child welfare issue and associated with increased risk of child maltreatment. The aim of the present study was to understand what social care outcomes children who live with parental substance misuse have, and to assess factors associated with those social care outcomes over a two-year period. The paper reports on a retrospective longitudinal study of 299 children all living with parental substance misuse and referred to one local authority in England. Data were collected from children's social work case files about procedural social care outcomes and factors which may be associated with those outcomes. Using cluster analysis, a new typology of children's longitudinal trajectories through the children's social care system was developed, consisting of five distinct types. Analysis indicated that some children received too little intervention from children's social care despite ongoing concerns, while other children were potentially unnecessarily caught up in the social care system. Factors associated with children having the poorest outcomes were: caregiver instability resulting from substance misuse, parenting capacity and household instability. The study's findings indicate that some children who live with parental substance misuse are at significant risk of harm, but others are not and may be better supported through non-statutory services such as early help.  相似文献   
452.
There is much educational concern about the disproportionate punishment of racial/ethnic minority students within U.S. public schools. Research evidence indicates that school punishment exacerbates the already-known racial/ethnic inequalities within the educational system. What remains uncertain is if and how school punishment, justice, and fairness are moderating educational attainment for the children of immigrants. This study utilizes data from the Education Longitudinal Study of 2002 and incorporates multilevel analysis to examine how school punishment, justice, and fairness influence the educational attainment of children of immigrants. The study draws on straight-line and segmented assimilation frameworks to evaluate variation in these effects by immigrant generation. Findings do suggest that improved school procedural justice and fairness could enhance educational attainment as well as ameliorate the detrimental impact of school punishment; however, these patterns are segmented by immigrant generation and race/ethnicity.  相似文献   
453.
454.
Determining the meanings of words requires language learners to attend to what other people say. However, it behooves a young language learner to simultaneously encode relevant non-verbal cues, for example, by following the direction of their eye gaze. Sensitivity to cues such as eye gaze might be particularly important for bilingual infants, as they encounter less consistency between words and objects than monolingual infants, and do not always have access to the same word-learning heuristics (e.g., mutual exclusivity). In a preregistered study, we tested the hypothesis that bilingual experience would lead to a more pronounced ability to follow another's gaze. We used a gaze-following paradigm developed by Senju and Csibra (Current Biology, 18, 2008, 668) to test a total of 93 6- to 9-month-old and 229 12- to 15-month-old monolingual and bilingual infants, in 11 laboratories located in 8 countries. Monolingual and bilingual infants showed similar gaze-following abilities, and both groups showed age-related improvements in speed, accuracy, frequency, and duration of fixations to congruent objects. Unexpectedly, bilinguals tended to make more frequent fixations to on-screen objects, whether or not they were cued by the actor. These results suggest that gaze sensitivity is a fundamental aspect of development that is robust to variation in language exposure.  相似文献   
455.
Antecedents and correlates of sexual behavior among 167 (46% female) adolescents were examined in this multi‐informant longitudinal study. Data were collected at birth through middle adolescence. Data on number of sexual partners and contraception use at age 16 defined sexual abstinence (SAs, n=73), high‐risk sexual behavior (HRTs, n=45) and low‐risk sexual behavior (LRTs, n=49) groups. Moffitt's (1993) antisocial behavior taxonomy, problem behavior theory ( Jessor & Jessor, 1977 ), social control theory (Hierschi), and a biosocial model ( Udry, 1988 ) guided expectations of differential group prediction. Variables from each of three developmental periods (<age 12, ages 12–13, age 16) were significantly associated with sexual behavior groups. The most salient factors that differentiated LRTs from SAs were physical maturation at age 13 and romantic relationship progression and alcohol use at age 16. Romantic relationship progression and drug use at age 16 differentiated HRTs from SAs.  相似文献   
456.
The goal of this study was to investigate the impact of poverty and economic pressure upon the adjustment of mothers and children in immigrant Latino families. Participants included 56 first generation Latina mothers who completed questionnaires addressing economic difficulties, depression, social support, and behavior problems exhibited by their children (30 boys, 26 girls) who ranged in ages from 4 to 13. Results indicate that maternal depression mediates the relationship between maternal economic pressure and child adjustment. Social support was found to further moderate the relationship between maternal depression and child internalizing problems. Gender differences indicated that relations were stronger among mothers of boys than mothers of girls.  相似文献   
457.
Messages sent over Animal Rights-Talk, an electronic mail network devoted to the discussion of issues related to the animal rights movement, were analyzed. Messages typically fell into the following categories: questions and information, discussions of philosophical issues, ethical problems associated with the treatment of particular species, the politics of the animal rights movement, problems of moral consistency, the ethics of particular uses of non-human species (e.g., meat consumption, biomedical research with animal subjects), and matters pertaining to the internal life of the network (e.g., efforts at control of perceived norm violations). Debates between animal activists and animal researchers over the network often reflected the conflicting cosmologies of scientists and animal protectionists. We argue that computer bulletin boards offer a potentially important avenue for qualitative research.  相似文献   
458.
459.
The estimation of Bayesian networks given high‐dimensional data, in particular gene expression data, has been the focus of much recent research. Whilst there are several methods available for the estimation of such networks, these typically assume that the data consist of independent and identically distributed samples. It is often the case, however, that the available data have a more complex mean structure, plus additional components of variance, which must then be accounted for in the estimation of a Bayesian network. In this paper, score metrics that take account of such complexities are proposed for use in conjunction with score‐based methods for the estimation of Bayesian networks. We propose first, a fully Bayesian score metric, and second, a metric inspired by the notion of restricted maximum likelihood. We demonstrate the performance of these new metrics for the estimation of Bayesian networks using simulated data with known complex mean structures. We then present the analysis of expression levels of grape‐berry genes adjusting for exogenous variables believed to affect the expression levels of the genes. Demonstrable biological effects can be inferred from the estimated conditional independence relationships and correlations amongst the grape‐berry genes.  相似文献   
460.
Analysis of high dimensional data often seeks to identify a subset of important features and assess their effects on the outcome. Traditional statistical inference procedures based on standard regression methods often fail in the presence of high-dimensional features. In recent years, regularization methods have emerged as promising tools for analyzing high dimensional data. These methods simultaneously select important features and provide stable estimation of their effects. Adaptive LASSO and SCAD for instance, give consistent and asymptotically normal estimates with oracle properties. However, in finite samples, it remains difficult to obtain interval estimators for the regression parameters. In this paper, we propose perturbation resampling based procedures to approximate the distribution of a general class of penalized parameter estimates. Our proposal, justified by asymptotic theory, provides a simple way to estimate the covariance matrix and confidence regions. Through finite sample simulations, we verify the ability of this method to give accurate inference and compare it to other widely used standard deviation and confidence interval estimates. We also illustrate our proposals with a data set used to study the association of HIV drug resistance and a large number of genetic mutations.  相似文献   
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