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An evaluation of matching unknown writing inks with the United States International Ink Library 总被引:2,自引:0,他引:2
Laporte GM Arredondo MD McConnell TS Stephens JC Cantu AA Shaffer DK 《Journal of forensic sciences》2006,51(3):689-692
Utilizing a database of standards for forensic casework is a valuable resource. Undoubtedly, as more standards (and corresponding information about the specimens) are collected, there is a greater certainty of identification when a questioned and a known item cannot be distinguished after a series of analyses. The United States Secret Service and the Internal Revenue Service National Forensic Laboratory jointly maintain the largest known forensic collection of writing inks in the world, which is comprised of over 8500 ink standards collected worldwide, dating back to the 1920s. This study was conducted to evaluate the reliability of matching arbitrarily purchased pens with known inks from a database. One hundred pens were randomly obtained from a variety of sources and their respective ink compositions were compared with standards. Eighty-five of the inks were determined to be suitable for comparison utilizing optical examinations and thin-layer chromatography. Three of the inks did not match any of the specimens on record; one of these inks was similar to an ink from an identical brand of pen that was in the database, but had a modified formulation. 相似文献
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Since 1970, state and local governments have experienced two “insurance crises;” the first occurred in the mid- to late-1970s and the second in the mid-80s. The result has been a twenty-year period of time in which state and local governments have been able to afford insurance only intermittently-if insurance has been available at all. In response to this problem, local governments, government associations, and state governments created alternative risk-finartcing mechanisms to provide coverage for themselves. These mechanisms, commonly referred to as self-insurance pools, enable local governments within a state to pool together risks and resources to finance the costs of fortuitous losses. In 1988, the first comprehensive examination of pooling practices was undertaken through a nationwide survey. This article reports the findings from the first follow-up study since the 1988 survey and further extends knowledge of pooling and pooling practices. 相似文献
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Joseph LaPalombara William Frazer Laura Bloodgood Courtland L. Smith Jorge I. Domínguez Kenneth J. Mijeski Irene Tinker David G. Becker Robert Campbell Daniel Zirker Stanley A. Kochanek Young Whan Kihl James Cobbe Walle Engedayehu Joel Samoff 《Studies in Comparative International Development (SCID)》1995,30(2):68-103
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Thirty years have passed since the publication of "Cross-Subsidization:Pricing in Public Enterprises." The article rigorously definedcross-subsidization and is now a standard citation of regulatorsand scholars addressing the pricing of regulated multiproductfirms. The incremental cost test and the stand-alone cost test,however, have often been misunderstood and misapplied. Thisarticle answers the most common questions that have arisen inthe application of these tests for cross-subsidization and correctsthe most common errors that have been committed in their application. 相似文献
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Mastana SS Murry B Sachdeva MP Das K Young D Das MK Kalla AK 《Forensic science international》2007,169(2-3):266-273
We have analysed 13 autosomal STR loci in four endogamous tribal populations from two eastern states (Orissa and Nagaland) of India. The Gadaba, Kuvi Khond and Lotha Naga populations have not been analysed for microsatellite genetic variation previously. The allele frequencies for all loci are within the range observed in the geographical region and racial background, though some alleles showed greater variation. Departures from the Hardy-Weinberg equilibrium were tested by three methods and two loci (THO1 and TPOX) showed significant departures for all measures in Gadaba and Lotha Naga populations. The exclusion probability and discrimination probability were high for all analysed loci in all populations. There is no evidence for association of alleles among the STR loci studied. This allele frequency information will be useful for forensic, paternity and population genetic studies. 相似文献