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941.
Chemical composition of fingerprints for gender determination 总被引:3,自引:0,他引:3
This work investigates the chemical nature of fingerprints to ascertain whether differences in chemical composition or the existence of chemical markers can be used to determine personal traits, such as age, gender, and personal habits. This type of information could be useful for reducing the pool of potential suspects in criminal investigations when latent fingerprints are unsuitable for comparison by traditional methods. Fingertip residue that has been deposited onto a bead was extracted with a solvent such as chloroform. Samples were analyzed by gas chromatography/mass spectrometry (GC/MS). The chemical components identified include fatty acids, long chain fatty acid esters, cholesterol and squalene. The area ratios of ten selected components relative to squalene were calculated for a small preliminary experiment that showed a slight gender difference for three of these components. However, when the experiment was repeated with a larger, statistically designed experiment no significant differences between genders were detected for any of the component ratios. The multivariate Hotelling's T2 test that tested all ten-component ratios simultaneously also showed no gender differences at the 5% significance level. 相似文献
942.
Abraham C. Becker 《后苏联事务》2013,29(4):291-329
A leading specialist on Soviet economics examines the heavily politicized debate on the CIA's estimates of the rate of growth and comparative size of the Soviet economy during the period 1960-1985. The author finds little evidence to support the common indictment that the CIA seriously misestimated the Soviet growth record. He finds somewhat greater reason to believe that the Agency's comparative size ratios were overstated. And he finds grounds to question whether CIA dealt effectively with the limitations of the size and growth measures in the late 1970s and early 1980s. Journal of Economic Literature Classification Numbers: P27, P24, P52. 相似文献
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944.
Charles Onunaiju 《北京周报(英文版)》2021,64(9):28-29
WTO new head is on a mission to advance the prospects of common development The World Trade Organization(WTO),the rule-making body for the global trading system that started life on January 1,1995,has just had its glass ceiling shattered,with the first woman climbing to the apex of its structure. 相似文献
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948.
Separating the commercialisation of agriculture from other programmes to improve access to formal credit for smallholder farmers is a source of dramatic failures of most programmes. Despite the popularity of value chain financing, livestock agriculture remains marginalised. This paper analyses the MAFISA-NERPO Livestock Credit Scheme, a scheme which provides value chain financial products in order to improve the cash incomes of smallholder farmers in South Africa. Evidence shows that more than 80% of participating farmers receive average annual incomes of US$30,000. This implies that this scheme has addressed those factors hindering effectiveness and efficiency of smallholder credit institutions, using value chain finance. 相似文献
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The cost of producing multifamily affordable housing may differ based on development type. Past attempts to compare the costs of producing multifamily housing through new construction or acquisition-rehab have been limited by an inability to adjust for variations in unit quality among different projects. The authors overcome this challenge by estimating the costs of developing and maintaining a property over a 50-year life cycle. Applying this approach to a convenience sample of 269 properties, the authors find new construction associated with life-cycle costs that are 25% to 45% higher than those of acquisition-rehab. 相似文献