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ABSTRACT: Determination of the muzzle‐to‐target distance is often a critical factor in criminal and civil investigations involving firearms. However, seeing and recording gunshot residue patterns can be difficult if the victim's clothing is dark and/or bloodstained. Trostle reported the use of infrared film for the detection of burn patterns. However, only after the film is developed are the results visible and multiple exposures at different settings may be needed. The Video Spectral Comparator? 2000 (Foster & Freeman Ltd., Evesham, Worcestershire, U.K.) is an imaging instrument routinely used by forensic document examiners. Without use of specialized film could the VSC 2000 (at appropriate instrument settings) quickly, easily, and reliably provide instantaneous viewing, saving, and printing of gunshot residue patterns on dark and/or blood soaked clothing? At muzzle‐to‐target distances of 6, 12, and 18 in., test fires were made into five different types of dark clothing using eight different handguns of different calibers. Gunshot residues were detected for all eight calibers, and powder burn patterns were seen on dark clothing for all three target distances and calibers except 0.22 long rifle and 0.25 ACP. Bloodstains did not preclude the viewing of these patterns.  相似文献   
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The Society for the Protection of Motherhood (BfM) was the first organization in Germany to concern itself with a reform of sexual ethics and the transformation of the relationship between women and men—not only on a theoretical level but by actually providing support for single mothers and their children and initiating counselling centres to deal with sexual problems. At the same time, the BfM demanded legal equality for illegitimate children, the decriminalization of abortion and the right of women to sue for divorce. In raising these issues, the BfM trod on difficult ground since they were not ‘popular’ topics of discussion within German society around the turn-of-the-century. The chairwoman of the BfM, Helene Stöcker, who was among the first women to study and obtain a doctorate in Germany, put the Society's ideas into practice in her relationship of ‘free love and marriage’ with her partner, the lawyer Bruno Springer. Indeed, it was the policy of the BfM to encourage progressive men to join the organization and work in partnership with the women, while most of the other groups on the radical wing of the bourgeois women's movement chose to work autonomously from men. Over the years, the BfM's priorities changed and its members moved in different directions: while the ‘moderates’ wanted to retain the family as the nucleus of the state, the more radical members went in search of new forms of relationship, attempting thereby to expose society's double standard of morality.  相似文献   
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Y chromosome-specific short tandem repeat (Y-STR) analysis has become another widely accepted tool for human identification. The PowerPlex Y System is a fluorescent multiplex that includes the 12 loci: DYS19, DYS385a/b, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438 and DYS439. This panel of markers incorporates the 9-locus European minimal haplotype (EMH) loci recommended by the International Y-STR User Group and the 11-locus set recommended by the Scientific Working Group on DNA Analysis Methods (SWGDAM). Described here are inter-laboratory results from 17 developmental validation studies of the PowerPlex Y System and include the following results: (a) samples distributed between laboratories and commercial standards produced expected and reproducible haplotypes; (b) use of common amplification and detection instruments were successfully demonstrated; (c) full profiles were obtained with standard 30 and 32 cycle amplification protocols and cycle number (24-28 cycles) could be modified to match different substrates (such as direct amplification of FTA paper); (d) complete profiles were observed with reaction volumes from 6.25 to 50 microL; (e) minimal impact was observed with variation of enzyme concentration; (f) full haplotypes were observed with 0.5-2x primer concentrations; however, relative yield between loci varied with concentration; (g) reduction of magnesium to 1mM (1.5 mM standard) resulted in minimal amplification, while only partial loss of yield was observed with 1.25 mM magnesium; (h) decreasing the annealing temperature by 2-4 degrees C did not generate artifacts or locus dropout and most laboratories observed full amplification with the annealing temperature increased by 2 degrees C and significant locus dropout with a 4 degrees C increase in annealing temperature; (i) amplification of individual loci with primers used in the multiplex produced the same alleles as observed with the multiplex amplification; (j) all laboratories observed full amplification with >or = 125 pg of male template with partial and/or complete profiles observed using 30-62.5 pg of DNA; (k) analysis of < or = 500 ng of female DNA did not yield amplification products; (l) the minor male component of a male/female mixture was observed with < or =1200-fold excess female DNA with the majority of alleles still observed with 10,000-fold excess female; (m) male/male mixtures produced full profiles from the minor contributor with 10-20-fold excess of the major contributor; (n) average stutter for each locus; (o) precision of sizing were determined; (p) human-specificity studies displayed amplification products only with some primate samples; and (q) reanalysis of 102 non-probative casework samples from 65 cases produced results consistent with original findings and in some instances additional identification of a minor male contributor to a male/female mixture was obtained. In general, the PowerPlex Y System was shown to have the sensitivity, specificity and reliability required for forensic DNA analysis.  相似文献   
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Y chromosome-specific short tandem repeat (Y-STR) analysis has become another widely accepted tool for human identification. The PowerPlex Y System is a fluorescent multiplex that includes the 12 loci: DYS19, DYS385a/b, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438 and DYS439. This panel of markers incorporates the 9-locus European minimal haplotype (EMH) loci recommended by the International Y-STR User Group and the 11-locus set recommended by the Scientific Working Group on DNA Analysis Methods (SWGDAM). Described here are inter-laboratory results from 17 developmental validation studies of the PowerPlex Y System and include the following results: (a) samples distributed between laboratories and commercial standards produced expected and reproducible haplotypes; (b) use of common amplification and detection instruments were successfully demonstrated; (c) full profiles were obtained with standard 30 and 32 cycle amplification protocols and cycle number (24-28 cycles) could be modified to match different substrates (such as direct amplification of FTA paper); (d) complete profiles were observed with reaction volumes from 6.25 to 50 microL; (e) minimal impact was observed with variation of enzyme concentration; (f) full haplotypes were observed with 0.5-2x primer concentrations; however, relative yield between loci varied with concentration; (g) reduction of magnesium to 1mM (1.5 mM standard) resulted in minimal amplification, while only partial loss of yield was observed with 1.25 mM magnesium; (h) decreasing the annealing temperature by 2-4 degrees C did not generate artifacts or locus dropout and most laboratories observed full amplification with the annealing temperature increased by 2 degrees C and significant locus dropout with a 4 degrees C increase in annealing temperature; (i) amplification of individual loci with primers used in the multiplex produced the same alleles as observed with the multiplex amplification; (j) all laboratories observed full amplification with >or = 125 pg of male template with partial and/or complete profiles observed using 30-62.5 pg of DNA; (k) analysis of < or = 500 ng of female DNA did not yield amplification products; (l) the minor male component of a male/female mixture was observed with < or =1200-fold excess female DNA with the majority of alleles still observed with 10,000-fold excess female; (m) male/male mixtures produced full profiles from the minor contributor with 10-20-fold excess of the major contributor; (n) average stutter for each locus; (o) precision of sizing were determined; (p) human-specificity studies displayed amplification products only with some primate samples; and (q) reanalysis of 102 non-probative casework samples from 65 cases produced results consistent with original findings and in some instances additional identification of a minor male contributor to a male/female mixture was obtained. In general, the PowerPlex Y System was shown to have the sensitivity, specificity and reliability required for forensic DNA analysis.  相似文献   
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In this paper we extend our earlier work on science and engineering faculty disclosure and licensing activity to examine a characteristic of faculty ignored in our earlier work – the gender of faculty in our database of over 4500 faculty at 11 major universities. Not surprisingly, women comprise only 8.55% of the faculty in our sample. They are most represented in the biological sciences and the women in the sample are more likely to be younger faculty. The most striking result from highlighting women in the sample is that women are less likely to disclose inventions than men despite the fact that there are no significant differences in publication patterns. While disclosure activity varies by gender, we find that the disclosure activity of women and men converges over the period of our sample.JEL Classification: J16, L3, O3Financial support was provided by National Science Foundation (SES 0094573), the Alan and Mildred Peterson Foundation and the Ewing Marion Kauffman Foundation.  相似文献   
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