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171.
A series of validation experiments was performed for a Y chromosome specific STR multiplex system following the suggestions made by the Technical Working Group DNA Analysis Methods (TWGDAM). The multiplex PCR products were detected on Perkin-Elmer 373 and 377 automated sequencers using two labeling colors. No problems regarding the stability, robustness and sensitivity of the Y STR multiplex were observed. Mixture studies revealed a cut off rate similar to autosomal STRs for mixtures of male DNAs and no interference of any female admixture. The comparison of the Y STR results to the autosomal typing results for 56 nonprobative semen stains and swabs, showed a slightly higher success rate in detecting the semen donor’s alleles for the Y STR multiplex. Two examples are shown to illustrate the usefulness of Y STR typing for DNA mixtures. In one case the Y STR results confirmed an isolated exclusion; in the other case, the interpretation of a mixture was clarified since the Y STR results proved the presence of DNA from at least two semen donors. Y STR typing is a valuable addition to the forensic DNA testing panel.  相似文献   
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I owe a debt of gratitude to Professors Hugh Bevan and Michael Freeman for reading and commenting helpfully on earlier drafts. The usualcaveat applies.  相似文献   
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Structural change is endemic in the Eastern European economies and the newly emerging Commonwealth of Independent States yet conventional econometric modelling techniques proceed under the assumption that there is a structurally stable ‘true’ economy to be discovered. This paper extends the analysis of Hall (1993) by exploring the consequences of endemic structural change for forecasting and building structural econometric models. We propose a model formulation which makes the econometric model itself able to adjust its parameters in the light of economic change using the Kalman Filter. The paper then illustrates this approach by building a small model of Romania and investigating its forecasting properties.  相似文献   
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A study was conducted to compare the interpretive and coping responses of female and male survivors of incest and female survivors of sexual assault by a nonrelative. Twenty-eight persons responded to a questionnaire that asked them to provide an account of the nature of an assault(s), the role of confidants in helping them cope with the assault, how they coped and tried to understand the assault over time, how they felt the assault affected their close relationships, and how they evaluated their current state of recovery. The results for male and female incest groups were similar in revealing great difficulty in coping and in having adult close relationships. These two groups showed more continuing lack of resolution than did the female nonfamilial survivors. The male group of incest survivors showed the greatest overall difficulty. The findings are discussed in terms of the roles of searching for meaning via account-making and confiding as ways of dealing with long-term, major Stressors in people's lives.  相似文献   
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Recently, a sample containing cyclopropylfentanyl was analyzed at this laboratory. Cyclopropylfentanyl began to appear in the United States' illicit drug markets in 2017. Unfortunately, cyclopropylfentanyl presents an analytical challenge due to its mass spectrum being almost identical to that of crotonylfentanyl. There are two possible isomers of crotonylfentanyl, Z- and E- crotonylfentanyl. In order to provide sufficient analytical data to distinguish the two isomers of crotonylfentanyl and cyclopropylfentanyl, crotonylfentanyl was synthesized and fully characterized. Each isomer was analyzed via nuclear magnetic resonance spectroscopy, gas chromatography–mass spectrometry, and Fourier transform infrared spectroscopy. During the synthesis of crotonylfentanyl, an unknown compound was formed. The identification of this compound and the analytical characterization of the two isomers of crotonylfentanyl are presented. Through the comparison of these compounds, it was confirmed that cyclopropylfentanyl can be differentiated from crotonylfentanyl.  相似文献   
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