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251.
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
252.
Louis J. Cantori Augustus Richard Norton Carrie Rosefsky Wickham Judith S. Yaphe Michael C. Hudson Eric Davis 《中东政策》2005,12(1):97-121
These contributions were presented at a roundtable of the Conference Group on the Middle East, "Evaluating the Bush Menu for Change in the Middle East," at the American Political Science Association Annual Meeting, Chicago, September 5, 2004. 相似文献
253.
How large a role does the family play in civic development? This paper examines an important aspect of family influence by tracing the impact of divorce on voter turnout during adolescence. We show that the effect of divorce among white families is large, depressing turnout by nearly 10 percentage points. Using data from the National Education Longitudinal Study of 1988, we demonstrate that the impact of divorce varies by racial group and can rival the impact of parents’ educational attainment, which is generally regarded as the most important non-political characteristic of one’s family of origin. We attempt to explain the divorce effect by examining the mediating impacts of parental voter turnout, active social learning, income loss, child–parent interaction, residential mobility, and educational attainment. 相似文献
254.
255.
Stewart JE Aagaard PJ Pokorak EG Polanskey D Budowle B 《Journal of forensic sciences》2003,48(3):571-580
Laser-induced detection of fluorescent labeled PCR products and multi-wavelength detection (i.e., multicolor analysis) enables rapid generation of mtDNA sequencing profiles. Traditionally, polyacrylamide slab gels have been used as the electrophoretic medium for mtDNA sequencing in forensic analyses. Replacement of slab gel electrophoresis with capillary electrophoresis (CE) can facilitate automation of the analytical process. Automation and high throughput can be further enhanced by using multicapillary electrophoretic systems. The use of the ABI Prism 3100 Genetic Analyzer (ABI 3100, Applied Biosystems, Foster City, CA) as well as the ABI Prism 310 Genetic Analyzer (ABI 310, Applied Biosystems, Foster City, CA) were evaluated for mtDNA sequencing capabilities and compared with sequencing results obtained on the platform currently in use in the FBI Laboratory (the ABI Prism 377 DNA Sequencer, ABI 377, Applied Biosystems, Foster City, CA). Various studies were performed to assess the utility of the ABI 3100, as well as the ABI 310 for mtDNA sequencing. The tests included: comparisons of results obtained among the ABI 3100, the ABI 310 and the ABI 377 instruments; comparisons of results obtained within and between capillary arrays; evaluation of capillary length; evaluation of sample injection time; evaluation of the resolution of mixtures/heteroplasmic samples; and evaluation of the sensitivity of detection of a minor component with reduced template on the ABI 3100. In addition, other studies were performed to improve sample preparation; these included: comparison of template suppression reagent (TSR, Applied Biosystems, Foster City, CA) versus formamide; the use of Performa DTR Gel Filtration Cartridges (Edge BioSystems Inc., Gaithersburg, MD) versus Centri-Sep Spin Columns (Princeton Separations, Adelphia, NJ) for product purification after cycle sequencing; and sample stability after denaturation. The data support that valid and reliable results can be obtained using either capillary electrophoresis instrument, and the quality of sequencing results are comparable to or better than those obtained from the ABI 377 instrument. 相似文献
256.
Analysis of a contaminated brake fluid revealed the contaminant to be power steering fluid. The sample received at the laboratory presented two immiscible phases, which were both organic. Both fluids were analyzed by GC-MS and compared with a library of known automotive fluids. The bottom layer (brake fluid) consisted of glycols while the top layer (power steering fluid) consisted of aliphatics ranging from C16 to C25+. An interesting phenomenon of diffusion of some of the glycols from the brake fluid phase into the power steering fluid phase was observed and needs to be taken into consideration in the interpretation of the results. 相似文献
257.
Capillary electrophoresis is widely used in the forensic community for the analysis of Short Tandem Repeat DNA. The CE system used in most forensic laboratories allows the user to modify standard operational protocols to accommodate some samples that fall outside of interpretational guidelines. We have made operational changes and monitored system resolution and the ability of the software to identify alleles as a result of these modifications. Increased amount of amplified product in the injection preparation, lengthened injection times or repeated injections of the same sample were all investigated along with variations in run voltages. Certain protocol modifications offer some advantages to the analysis of STRs and may allow the analyst to avoid extraction of additional portions of crime scene samples to achieve interpretable results. 相似文献
258.
Eric M. Patashnik 《管理》1999,12(2):147-174
Long the lifeblood of public administration, budgeting in the United States acquired a new importance during the 1980s and 1990s because of the fiscalization of the policy debate. But how much has American national budgeting really changed? This article examines the evolution of federal budgeting over the past half-century, exploring such developments as the massive growth of entitlements, congressional budget reform, and the protracted battle over the budget deficit. It finds that year-to-year changes in budget results have been relatively small even while budgetary rules and procedures have experienced sweeping change. At the same time, the composition of federal spending has undergone a quiet revolution. The traditional concept of budgetary incrementalism offers an incomplete explanation for these dynamics. To make sense of them, the article focuses on two key factors: the impact of policy inheritances, and the role of actors' causal and normative beliefs. These factors shape the ideational and material context within which boundedly rational actors negotiate decisions. The tension between changes in ideas and entrenched budgetary commitments has often served to stimulate institutional reform. 相似文献
259.
This paper draws upon data from the Pittsburgh site of the MacArthur Foundation's Risk Assessment Study, a large-scale study of violence risk among persons discharged from psychiatric hospitals, to examine the effect of the neighborhood context on risk of violence. This paper has two purposes: (1) to assess the extent to which the inclusion of neighborhood characteristics enhances violence prediction models—models that traditionally only include individual-level characteristics; and (2) to assess the consistency of individual level risk factors across different neighborhood contexts. Results indicate that neighborhood poverty has an impact over and above the effects of individual characteristics in identifying cases with violence. These findings support efforts to include neighborhood context in the assessment and management of violence risk among discharged psychiatric patients. 相似文献
260.
Randolph Sloof has written a comment on the lobbying-as-signalling model in Rasmusen (1993) in which he points out an equilibrium I missed and criticizes my emphasis on a particular separating equilibrium (see this issue). In this response, I discuss how to interpret multiple equilibria in games and how to interpret mixed strategy equilibria in which two types of player with identical incentives must pick different mixing probabilities. 相似文献