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121.
LaPorte GM Wilson JD Mancke SA Payne JA Ramotowski RS Fortunato SL 《Journal of forensic sciences》2003,48(5):1163-1171
Thermal transfer printing refers to printing processes that utilize heat to produce an image by either physical or chemical means or by a combination of both. As the technology has improved and the supplies have become less expensive, the use of thermal printing in the personal and business markets has increased significantly. Specifically, dye diffusion thermal transfer and thermal mass transfer have become predominant in the production of counterfeit credit cards, drivers' licenses, and other types of documents produced on plastic media. Chemical analysis by means of thin layer chromatography (TLC) has proven to be useful in characterizing various types of inks (e.g., writing and inkjet inks). In this study, the authors examined 81 different samples that included a total of 54 printer samples (43 photographic prints on paper and eleven plastic card samples) and 27 printer ribbons. A new TLC method was developed and tested utilizing a solvent system (80% n-hexane, 3% methyl ethyl ketone, and 17% ethyl acetate) that is capable of producing excellent resolution. 相似文献
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123.
Benner BA Goodpaster JV DeGrasse JA Tully LA Levin BC 《Journal of forensic sciences》2003,48(3):554-563
This paper discusses results of a supercritical fluid extraction-gas chromatography/mass spectrometry (SFE-GC/MS) study of small samples ( 100 microg to 1 mg) of human scalp hair. The method offers a number of benefits including greater sensitivity than liquid extraction methods because the entire extractable mass is transferred to the analytical system, compared with only a few percent from a conventional liquid extraction/injection. The project's goals were to determine if SFE-GC/MS analyses of the surface-extractable components of an individual's hair yield consistent chemical profiles and to investigate if the profiles are sufficiently different to distinguish them from those of other individuals. In addition, the mtDNA sequences from ten of the same individuals used in the SFE-GC/MS study from four family units were determined, and, while the families were distinguishable, the maternal relations yielded identical sequences. In tandem, SFE-GC/MS and mtDNA techniques may provide valuable complementary data from forensic hair samples. 相似文献
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We develop an empirical estimator directly from an extensive-formcrisis bargaining game with incomplete information and discussits features and limitations. The estimator makes it possibleto draw inferences about states' payoffs from observationaldata on crisis outcomes while remaining faithful to the theorizedstrategic and informational structure. We compare this estimatorto one based on a symmetric information version of the samegame, using the quantal response equilibrium proposed in thiscontext by Signorino (1999, American Political Science Review93:279298). We then address issues of identificationthat arise in trying to learn about actors' utilities by observingtheir play of a strategic game. In general, a number of identifyingrestrictions are needed in order to pin down the distributionof payoffs and the effects of covariates on those payoffs. 相似文献
126.
In a large sample of over 4,000 Chinese residents in the Wuling and Sino-Vietnamese border regions of China, females had a higher incidence of ever wishing that they were dead. This sex difference was found regardless of marital status, age, and occupation. 相似文献
127.
Forensic DNA laboratories worldwide have begun using multiplexed STR systems to decrease analysis time and increase sample throughput. The loci used in these systems are basically "nonsense" regions of human DNA. However, due to the chromosome on which some of these loci are located, various genetic abnormalities can sometimes be detected. This paper will show one such abnormality--Klinefelter's Syndrome--and the process used to show the possibility of this defect in two undiagnosed males using peak height ratios at the Amelogenin locus, and X-Y STRs. 相似文献
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Jedrzejowska ZK 《Forensic science international》2001,117(1-2):145-151
The aim of this work is to prove the application of craniometry in determining the identity of unknown bodies. There is a great correlation between the viscero-cranium appearance and the osseous structure, the said correlation following mathematical rules and thus being possible to be calculated. Various segments of the skull and different size of the angles they make with each other are directly responsible for the graphic profile of viscero-cranium. The nasal bones and their angle are the basis to determine the shape and size of the nose. 相似文献
130.