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101.
Parson W Brandstätter A Alonso A Brandt N Brinkmann B Carracedo A Corach D Froment O Furac I Grzybowski T Hedberg K Keyser-Tracqui C Kupiec T Lutz-Bonengel S Mevag B Ploski R Schmitter H Schneider P Syndercombe-Court D Sørensen E Thew H Tully G Scheithauer R 《Forensic science international》2004,139(2-3):215-226
This paper presents an overview of the organisation and the results of the collaborative exercises (CE) of the European DNA Profiling (EDNAP) Group's mitochondrial DNA population database project (EMPOP). The aim of the collaborative exercises was to determine whether uniformity of mtDNA sequencing results could be achieved among different laboratories. These were asked to sequence either the complete mtDNA control region or the two hypervariable regions HVI (16024-16365) and HVII (73-340) from DNA extracts, buccal swabs or bloodstains, proceeding in accordance with the protocol and strategies used in each individual laboratory. The results of the collaborative exercises were employed to identify possible sources of errors that could arise during the analysis and interpretation of mtDNA profiles. These findings were taken as a basis to tentatively make suitable arrangements for the construction of a high quality mtDNA database. One hundred fifty mtDNA profiles were submitted to the evaluating laboratory, and disaccording profiles were classified into four groups corresponding to the source of error: clerical errors, sample mix-ups, contaminations and discrepancies with respect to the mtDNA nomenclature. Overall, 14 disaccording haplotypes (16 individual errors) were observed. The errors included 10 clerical errors, 3 interpretation problems, 2 cases of sample mix-up and 1 case of point heteroplasmic mixture, where the 2 sequencing reactions brought inconsistent base calls. This corresponds to an error rate of 10.7% in a virtual mtDNA database consisting of the collaborative exercise results. However, this estimate is still conservative compared to conclusions drawn by authors of meanwhile numerous publications critically reviewing published mtDNA population databases. Our results and earlier published concerns strongly emphasize the need for appropriate safety regulations when mtDNA profiles are compiled for database purposes in order to accomplish the high standard required for mtDNA databases that are used in the forensic context. 相似文献
102.
103.
This study investigated the possibility of recovering a bomb assembler's DNA from an exploded pipe bomb device. Metal and polyvinyl chloride (PVC) pipes were examined to determine if one surface type would allow better DNA recovery than the other. Ten subjects each handled components of one metal and one PVC pipe bomb. The bombs were exploded, the fragments were collected and swabbed using the double swab technique, and the samples were extracted, quantified, amplified, and genotyped using polymerase chain reaction/short tandem repeat (PCR/STR). Of the 20 bombs handled by the subjects, four bombs gave reportable results that matched the subject's known DNA profiles. An additional eight profiles, also matching the subject's known DNA profiles, were generated but were below the reportable threshold. There was no difference in the success rate of obtaining DNA profiles related to the use of either PVC or metal in the manufacture of the pipe bomb. The variables that appeared to have the greatest influence on the success of generating a DNA profile were the amount of fragmentation and subsequent recovery of the bomb fragments. It is suspected that successful DNA profiling could also be dependent upon the bomb assembler's propensity to slough skin cells on objects they handled. 相似文献
104.
Heather E. Campbell Karen Gerdes Sue Steiner 《Journal of policy analysis and management》2005,24(3):611-620
Some studies suggest that instructors' looks are important determinants of their Student Evaluations of Teaching (SET) results. Yet the studies examining this proposition leave out many independent variables that have been found to be important determinants of SETs in the SET literature. This study adds in most such factors and finds that, controlling for these other factors, attractiveness has no effect in our data. We conclude that earlier findings indicating that instructor appearance is important are likely due to omitted variable bias. © 2005 by the Association for Public Policy Analysis and Management 相似文献
105.
A comparison of adjustment methods to test the robustness of an STR DNA database comprised of 24 European populations 总被引:3,自引:0,他引:3
Gill P Foreman L Buckleton JS Triggs CM Allen H 《Forensic science international》2003,131(2-3):184-196
An aim of the European Network of Forensic Science Institutes (ENFSI) is to produce a DNA database of second generation multiplex (SGM) STR profiles that is representative of the resident cosmopolitan populations. To achieve this, data were collected from 24 different populations. All of the data were combined to form one database of 5700 profiles from which allele proportions were calculated. The robustness of this combined European database was tested by estimating parameter d for every DNA profile, where d=log(10)(Pm(c)/Pm(E)) Pm(c) is the match probability of the profile calculated from its cognate database and Pm(E) is the match probability of the combined European database. Overall there was a small tendency for Pm(c)>Pm(E) primarily because of sampling bias. This bias was removed by the simple expediency of applying an adjustment factor to the calculation of Pm(E). These were selected from the Balding size bias correction, the Balding and Nichols Fst correction, a minimum allele proportion (between 0.01 and 0.02), an upper bound of a 95% confidence interval (CI) and a lower bound on the genotype match probability. It was demonstrated that a single European database is a feasible proposition. A combination of different adjustment methods can be used to ensure that the result is conservative relative to the cognate database, and their effect measured by parameter d. 相似文献
106.
Misreport is a serious problem because inaccurate data may lead to erroneous substantive conclusions. This study examines the systematic misreport for the eventual presidential nominee in the American National Election Studies (ANES) presidential primary vote question. Using various data sources, this study demonstrates that misreport in presidential primaries is a serious problem leading to possible misinterpretation of the negative carryover hypothesis. Misreport also may be a product of time of interview. Earlier interviewing may help to solve part of the misreport problem. 相似文献
107.
Linda Rose-Krasnor Michael A. Busseri Teena Willoughby Heather Chalmers 《Journal of youth and adolescence》2006,35(3):365-379
Research has linked youth activity involvement to positive development. However, past studies have confounded at least two separable dimensions of involvement: breadth (number of activities) and intensity (participation frequency). Theory and the limited available evidence suggest that these dimensions may make independent contributions to development. Based on self-reports from 7430 high school students, this study assessed whether breadth and intensity dimensions were related to each other, to a typical aggregate measure of involvement, and to various indicators of positive development. Breadth and intensity were moderately interrelated and, in combination, they explained the majority of the variance in the typical involvement measure. Both dimensions were positively related to each development index. When examined simultaneously, only breadth had a unique relation with each developmental index. Further, evidence of nonlinear effects was found. Findings were consistent across age levels. Implications for measurement of involvement and interpretations of the extant research are discussed.
相似文献
Linda Rose-KrasnorEmail: |
108.
This article reviews the way in which three very different international organisations concerned with reproductive health policy responded to the reproductive rights agenda during the 1990s. The intention is not to evaluate these responses but to describe how these organisations saw their roles with respect to establishing and promoting reproductive rights in developing countries. We seek to explore their different strategies of defining and interpreting rights, to examine the imperatives behind these strategies and to consider how these variously fed into the practical actions and agendas with which these organisations were engaged. The organisations included were the Women's Global Network for Reproductive Rights, the International Federation of Family Planning Associations and the UK's Department for International Development. Their diverse understandings about implementing reproductive rights contribute to a plural political environment in which these rights and their interpretation are debated. For all the three, their particular conception of reproductive rights is an important organising principle through which their efforts around reproductive health are given wider meaning. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
109.
This paper contributes to the environmental justice literature by addressing several outstanding issues in a single study. Using a cross-time data set that allows us to control for the prevalent "chicken-and-egg" or "which-came-first" problem, we analyze the relative importance of poverty and race/ethnicity in an analysis that includes economic costs, potential legal costs, and potential collective action. Because the most appropriate functional form is not obvious, we use several methods, including Tobit, Poisson, and ordinary least squares, on different forms of the dependent variable. In every case, controlling for the population present at the time of disamenity location and controlling the other factors mentioned, we find evidence of disproportionate collocation based on race/ethnicity, but not on poverty alone. We also find that the potential for collective action decreases the likelihood of receipt of the studied disamenities. 相似文献
110.
Substantial benefits can accrue from living in low-poverty neighborhoods, yet approximately 80% of the 2.2 million Housing Choice Voucher (HCV) recipients rent homes in moderate- or high-poverty census tracts. The Chicago Regional Housing Choice Initiative tested several ways to promote opportunity moves. It included the first experiment that tests whether two types of light-touch incentives induce opportunity moves for HCV recipients who had requested a moving voucher. Based on the 2,005 HCV recipients in the study, we found that neither the offer of a $500 grant nor the offer of a $500 grant coupled with free mobility counseling induced opportunity moves. The receipt of mobility counseling also did not boost opportunity moves. Regardless of the type of offer, 11%–12% of participants moved to opportunity neighborhoods. Despite requesting a moving voucher, half of the study participants remained in place, indicating significant barriers to moving. We offer potential reasons for the results and conclude with two recommended pilots to increase opportunity moves. 相似文献