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If inquiries are about learning the lessons of the past, why do they appear to find the same failings time and again? Bristol, Mid Staffordshire, Morecambe Bay, Liverpool Community Health are all examples of where culture went wrong. The lack of learning from inquiries is a prominent concern and one raised elsewhere in this issue. In this article, I explore why it might be that culture is repeatedly found to be the cause of healthcare failures. I start by reviewing perspectives on what culture is and the degree to which it is possible change it. I examine how culture was described in the Bristol, Mid Staffordshire, Morecambe Bay and Liverpool inquiries and question whether these are the same cultures, with the same problems, or whether they are different. I discuss possible explanations for apparent similarities, describe how cultural change occurs and conclude by drawing out the implications of focussing on culture as a threat to patient safety.  相似文献   
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There is a dearth of literature that examines rural youths’ school transition and adaptation over the middle and high school years. Given rural education challenges, this study examines rural youths’ developmental trajectories of self-reported grades and affective and behavioral educational outcomes (i.e., school belonging, value of education, school misbehavior, and extracurricular activity participation). The cohort-sequential study consisted of 3,312 African American and White youth (50% female) who were surveyed over three and a half years, including the transition to high school. The results reveal significant changes in the outcomes from sixth to twelfth grade. For example, on average, school misbehavior increased over time while perceived school belonging decreased over time. Gender and race differences emerged; African American youth reported placing higher importance on education and less participation in school activities than White youth. The discussion focuses on the importance of examining rural adolescents’ educational pathways during the high school transition.  相似文献   
97.
Practical applications of genotypic surveys for forensic STR testing   总被引:8,自引:0,他引:8  
Legitimate genotype frequency estimation for multiallelic loci relies on component allele frequencies, as population surveys represent only a fraction of possible DNA profiles. Multilocus genotypes from two ethnic human populations, African American (n=195) and U.S. Caucasian (n=200), were compiled at 13 STR loci that are used worldwide in forensic investigation (D3S1358, vWA, FGA, D16S539, TH01, TPOX, CSF1PO, D8S1179, D21S11, D18S51, D5S818, D13S317, and D7S820). Sex-specific AmpFlSTR multiplexes provided stringent PCR-based STR typing specifically optimized for multicolor fluorescence detection. Heterozygosity at each STR locus ranged from 0.57 to 0.89 and encompassed from seven (TH01) to twenty-one (D21S11) alleles. Homozygosity tests, tests based on the distinct numbers of observed homozygous and heterozygous classes, log likelihood ratio tests, and exact tests assessed that the degree of divergence from theoretical Hardy-Weinberg proportions for all 13 STRs does not have practical consequence in genotype frequency estimation. Departures from linkage equilibrium, between loci, that imposed significance to forensic calculations were not indicated by observed variance of the number of heterozygous loci or Karlin interclass correlation tests. For forensic casework, reliable multilocus profile estimates may be obtained from the product of component genotype frequencies, each calculated through application of the Hardy-Weinberg equation to population database allele frequency estimates reported here. The average probability that two randomly selected, unrelated individuals possess an identical thirteen-locus DNA profile was one in 1.8x10(15) African Americans and one in 3.8x10(14) U.S. Caucasians.  相似文献   
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The relation between understanding of friendship and asociality was examined in 91 girls and 104 boys ranging in age from 9 to 17 years. Consistent with previous research, older children had higher understanding of friendship scores than younger children, and girls had higher understanding of friendship scores than boys. The relation between understanding of friendship and asociality was significant only for boys. Difficulty in understanding components of friendship appears to be one correlate of boys' delinquent tendencies.This article is based on the master's thesis of the first author, submitted to the University of Dayton.Received M.A. from University of Dayton. Main interest is clinical psychology.Received Ph.D. from University of Illinois at Chicago. Main interest is social cognitive development.  相似文献   
99.
The performance of the sub-population model first proposed by Balding and Nichols [D.J. Balding, R.A. Nichols, DNA profile match probability calculation: how to allow for population stratification, relatedness, database selection and single bands. Forensic Sci. Int. 64 (1994) 125-140] is examined using a simulation approach. This work extends the investigations of Curran et al. [J.M. Curran, J.S. Buckleton, and C.M. Triggs, What is the magnitude of the sub-population effect? Forensic Sci. Int. 135 (2003) 1-8]. In particular the effect of underestimating the coancestry coefficient, theta, and the effect of departures from the modelling assumptions were investigated. The model tends to give strongly conservative estimates if the estimate for the coancestry coefficient is accurate. If this coefficient is underestimated then a larger fraction of cases give non-conservative estimates. Departures from the modelling assumption that the sub-population is in Hardy-Weinberg and linkage equilibria appear to have very little effect.  相似文献   
100.
A set of 61 Y chromosome single-nucleotide-polymorphisms (Y-SNPs) is typed in a sample of 2517 individuals from 38 populations to infer the geographic origins of Y chromosomes in the United States and to test for paternal admixture among African-, European-, Hispanic-, Asian-, and Native-Americans. All of the samples were previously typed with the 11 core U.S. Y chromosome short tandem repeats (Y-STRs) recommended by SWGDAM, which revealed high levels of among ethnic group variation and low levels of among-population-within-ethnic-group variation. Admixture estimates vary greatly among populations and ethnic groups. The frequencies of non-European (3.4%) and non-Asian (4.5%) Y chromosomes are generally low in European-American and Asian-American populations, respectively. The frequencies of European Y chromosomes in Native-American populations range widely (i.e., 7-89%) and follow a West to East gradient, whereas they are relatively consistent in African-American populations (26.4+/-8.9%) from different locations. The European (77.8+/-9.3%) and Native-American (13.7+/-7.4%) components of the Hispanic paternal gene pool are also relatively constant among geographic regions; however, the African contribution is much higher in the Northeast (10.5+/-6.4%) than in the Southwest (1.5+/-0.9%) or Midwest (0%). To test for the effects of inter-ethnic admixture on the structure of Y-STR diversity in the U.S., we perform subtraction analyses in which Y chromosomes inferred to be admixed by Y-SNP analysis are removed from the database and pairwise population differentiation tests are implemented on the remaining Y-STR haplotypes. Results show that low levels of heterogeneity previously observed between pairs of Hispanic-American populations disappear when African-derived chromosomes are removed from the analysis. This is not the case for an unusual sample of European-Americans from New York City when its African-derived chromosomes are removed, or for Native-American populations when European-derived chromosomes are removed. We infer that both inter-ethnic admixture and population structure in ancestral source populations may contribute to fine scale Y-STR heterogeneity within U.S. ethnic groups.  相似文献   
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