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951.
OBJECTIVE: This qualitative study examined stakeholders' perceptions of the safety of youth ages 12 and older living in congregate care facilities within the New York City foster care system. The study explored the youth's physical safety, the safety of their personal belongings, the physical conditions of congregate care settings, and the relationship between staff quality and youth safety. METHOD: The study involved interviews with family court judges, representatives of private child welfare agencies, attorneys who represent children in foster care, social workers, representatives of advocacy and other relevant organizations in New York City, and former foster youth who had been placed in congregate care settings. RESULTS: Safety in congregate care environments was an issue of significant concern. Threats to the youth's safety were found to emanate from peer-on-peer violence, stealing of personal belongings, inappropriate staff conduct, and the poor physical conditions of facilities. Youth's sense of safety was strongly linked to staff quality, including staff ability to relate effectively to youth and to maintain control of congregate care environments. CONCLUSIONS: Existing regulations in New York State appear to have had little effect in ensuring the safety of youth in many group and residential care facilities. Steps to improve safety outcomes for youth in these settings are proposed.  相似文献   
952.
OBJECTIVES: To examine the prevalence of bullying behavior in adolescents from Cape Town and Durban, South Africa, and the association of these behaviors with levels of violence and risk behavior. METHOD: Five thousand and seventy-four adolescent schoolchildren in grade 8 (mean age 14.2 years) and grade 11 (mean age 17.4 years) at 72 Government schools in Cape Town and Durban, South Africa completed self-report questionnaires on participation in bullying, violent, anti-social and risk behaviors. RESULTS: Over a third (36.3%) of students were involved in bullying behavior, 8.2% as bullies, 19.3% as victims and 8.7% as bully-victims (those that are both bullied and bully others). Male students were most at risk of both perpetration and victimization, with younger boys more vulnerable to victimization. Violent and anti-social behaviors were increased in bullies, victims and bully-victims compared to controls not involved in any bullying behavior (p<.01 in all cases). Risk taking behavior was elevated for bullies and bully-victims, but for victims was largely comparable to controls. Victims were less likely to smoke than controls (odds ratio .83, p<.05). Bully-victims showed largely comparable violent, anti-social and risk taking behavior profiles to bullies. Bully-victims showed comparable suicidal ideation and smoking profiles to victims. CONCLUSIONS: Results were in keeping with Western findings. Involvement in bullying is a common problem for young South Africans. Bullying behavior can act as an indicator of violent, anti-social and risk-taking behaviors.  相似文献   
953.
PURPOSE: This paper examines individual, family, and neighborhood level predictors of resilience in adolescence and young adulthood and describes changes in resilience over time from adolescence to young adulthood in abused and neglected children grown up. METHOD: We use documented cases of childhood physical and sexual abuse and neglect (n=676) from a Midwestern county area during the years 1967-1971 and information from official records, census data, psychiatric assessments, and self-reports obtained through 1995. Analyses involve logistic regressions, replicated with Mplus to test for possible contextual effects. RESULTS: Almost half (48%) of the abused and neglected children in adolescence and nearly one-third in young adulthood were resilient. Over half of those who were resilient in adolescence remained resilient in young adulthood, whereas 11% of the non-resilient adolescents were resilient in young adulthood. Females were more likely to be resilient during both time periods. Being white, non-Hispanic decreased and growing up in a stable living situation increased the likelihood of resilience in adolescence, but not in young adulthood. Stressful life events and a supportive partner promoted resilience in young adulthood. Neighborhood advantage did not exert a direct effect on resilience, but moderated the relationship between household stability and resilience in adolescence and between cognitive ability and resilience in young adulthood. CONCLUSIONS: Ecological factors appear to promote or interfere with the emergence and stability of resilience following childhood maltreatment.  相似文献   
954.
Cognition-related brain responses to meaningful and meaningless figures were registered in 5-year-old kindergarten children who either had been subtyped as being at-risk of developing an L- or P-type dyslexia (LAL versus LAP) or who were not at-risk. While identifying, naming, or categorizing pictures, event-related potentials (ERP) were registered. Three cognition-related components were found: the N460, the P780, and the Slow Wave (SW). LAP-children produced weak N460 activity across tasks, whereas LAL children, and to a lesser degree, non-risk children produced robust task-dependent activity. This finding may indicate that LAP-children lack semantic input while processing the figures. P780 latencies to frequently occurring figures were found hemisphere-dependent: LAP-children showed longer latencies in the right than in the left hemisphere, whereas the distribution was reversed in the LAL and non-risk children. It was also found that the right hemisphere is generally responsible for a lion's share of the processing of figures and therefore it seems that the right hemisphere of LAP-children invests ample time in doing so. Whereas LAP-children showed largest SW amplitude differences between frequent and infrequent stimuli at posterior locations, LAL children did so at frontal locations. Assuming that the SW represents working-memory processes, it may be that working-memory in LAP-children deals with figure-relevant visual-spatial information and with figure-derived concepts in LAL children. Overall, the findings suggest that LAL and LAP represent two different groups of kindergartners at risk of dyslexia and that these differences, to some degree, fit with the presumed etiology of L- and P-type dyslexia.  相似文献   
955.
The present study examined the role of verbal working memory (memory span and tongue-twister), two-character Chinese pseudoword reading (two tasks), rapid automatized naming (RAN) (letters and numbers), and phonological segmentation (deletion of rimes and onsets) in inferential text comprehension in Chinese in 31 less competent comprehenders compared with 37 reading comprehension control students and 23 chronological age controls. It was hypothesized that the target students would perform poorly on these cognitive and linguistic tasks as compared with their controls. Furthermore, verbal working memory and pseudoword reading would explain a considerable amount of individual variation in Chinese text comprehension. RAN would have a nonsignificant role in text comprehension. Structural equation analyses and hierarchical multiple regression analyses generally upheld these hypotheses. Our findings support current literature of the role of verbal working memory in reading comprehension found in English. The results, however, suggest differential role of the constructs and the tasks in reading comprehension and provide some answers for comprehension impairment in Chinese students.  相似文献   
956.
Phonological awareness, phonological memory, and phonological access to lexical storage play important roles in acquiring literacy. We examined the convergent, discriminant, and predictive validity of these phonological processing abilities (PPA) in 389 3-, 4-, and 5-year-old children. Confirmatory factor analysis supported the validity of each PPA as separate from general cognitive ability and separate from each other. Multigroup structural equation modeling (SEM) with mean structure demonstrated that older preschoolers have better developed latent PPA than younger preschoolers but that the structure of PPA is equivalent. RAN was found uniquely associated with letter knowledge and text discrimination in younger preschoolers, and PA was found uniquely associated with word reading skills in older preschoolers. Finally, general cognitive ability was only indirectly associated with emergent literacy via PPA. These results highlight the importance of PPA in the early literacy development of English-speaking preschool children.  相似文献   
957.
Gödel’s proof     
In 1931, the great Austrian mathematician Kurt Gödel proved “all consistent axiomatic formulations of number theory include undecidable propositions”. This discovery of Gödel and its proof had enormous repercussions in mathematics and computer science. The proof hinged upon the writing of a self-referential mathematical statement, in the same way as the liar’s paradox — I am lying — is a self-referential statement. In this three-part article, we describe Gödel’s discovery and his famous proof.  相似文献   
958.
A.  J.  Dalton 《英语沙龙》2011,(2):18-19
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959.
A.  J.  Dalton 《英语沙龙》2011,(3):46-47
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960.
In this paper, a novel reconstruction technique based on level set method and algebraic reconstruction technique is proposed for multiphase flow computed tomography (CT) system. The curvature-driven noise reduction method is inserted into the conventional iteration procedure of algebraic reconstruction technique to improve the image quality and convergence speed with limited projection data. By evolving the image as a set of iso-intensity contours after each updation, the sufficient number of iterations for acceptable results is reduced by 80%-90%, while the image quality is enhanced obviously. Quantitative evaluation of image quality is given by using both relative image error and correlation coefficient. The resultant images can be utilized to detect flow regimes for monitoring industrial multiphase flow. Laboratory results demonstrate the feasibility of the proposed method. Phantoms of four typical flow regimes can be reconstructed from few-view projection data efficiently, and the corresponding image errors and correlation coefficients are acceptable for the cases tested in this paper.  相似文献   
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