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921.
Jill D. Humphreys Glenn Porter Michael Bell 《Forensic Science International Supplement Series》2008,178(1):46-53
Research into fingermark enhancement techniques has traditionally used visual comparisons and qualitative methods to assess their effectiveness based on the quality of the developed fingermark. However, with increasing research into the optimisation of these techniques the need for a quantitative evaluative method has arisen. Parameters for acceptable fingerprint quality are not well defined and generally encompass clear, sharp edges and high levels of contrast between the fingermark ridges and background material. Using these current parameters, a conclusive measurement of fingerprint quality and thus the effectiveness of development techniques cannot be achieved.This study presents a model through which an aspect of fingerprint quality can be objectively and impartially measured based on a relative contrast index, constructed through measuring the reflective intensity of the fingermark ridges against the background material. Using a fibre-optic spectrophotometer attached to a microscope with axial illumination, the intensity counts of the ridge detail and background material were measured and a logarithmic contrast index constructed. The microscope and spectrophotometer parameters were experimentally tested using a standard colour resolution chart with known reflective properties. The protocol was successfully applied to four sample groups: black inked fingerprints on white paper; latent fingermarks on white paper developed separately with ninhydrin and physical developer; and fingermarks in blood deposited on white tiles and enhanced with amido black. The contrast indices obtained quantitatively reflect the level of contrast and provide an indication of fingerprint quality through a numerical representation rather than previous qualitative methods. It has been suggested that the proposed method of fingerprint quantification may be viable for application in the forensic research arena as it allows the definitive measurement of contrast to aid the evaluation of fingermark detection and enhancement techniques. 相似文献
922.
Managing incidental findings in human subjects research: analysis and recommendations. 总被引:8,自引:8,他引:0
Susan M Wolf Frances P Lawrenz Charles A Nelson Jeffrey P Kahn Mildred K Cho Ellen Wright Clayton Joel G Fletcher Michael K Georgieff Dale Hammerschmidt Kathy Hudson Judy Illes Vivek Kapur Moira A Keane Barbara A Koenig Bonnie S Leroy Elizabeth G McFarland Jordan Paradise Lisa S Parker Sharon F Terry Brian Van Ness Benjamin S Wilfond 《The Journal of law, medicine & ethics》2008,36(2):219-48, 211
No consensus yet exists on how to handle incidental findings (IFs) in human subjects research. Yet empirical studies document IFs in a wide range of research studies, where IFs are findings beyond the aims of the study that are of potential health or reproductive importance to the individual research participant. This paper reports recommendations of a two-year project group funded by NIH to study how to manage IFs in genetic and genomic research, as well as imaging research. We conclude that researchers have an obligation to address the possibility of discovering IFs in their protocol and communications with the IRB, and in their consent forms and communications with research participants. Researchers should establish a pathway for handling IFs and communicate that to the IRB and research participants. We recommend a pathway and categorize IFs into those that must be disclosed to research participants, those that may be disclosed, and those that should not be disclosed. 相似文献
923.
BERTIE AHERN T.D. 《今日中国(英文版)》2010,(6):26-26
IN 2010, in the midst of economic turmoil, Irish society is enriched because of its close friendship with China and the Chinese people; a friendship that is based on mutual respect, cultural understanding and trust. 相似文献
924.
A.M. Lagoa T. Magalhães M.F. Pinheiro 《Forensic Science International: Genetics Supplement Series》2008,1(1):48-49
In this work we aimed to compare the application of increasing PCR cycle number, whole genome amplification and nested-PCR on fingerprints genetic analysis. Results were compared for correct alleles, allele dropin and allelic dropout. We concluded that increasing the number of PCR cycles is yet the best way to attain the required sensitivity. 相似文献
925.
D.J. French R.L. Howard N. Gale T. Brown D.G. McDowell P.G. Debenham 《Forensic Science International: Genetics Supplement Series》2008,2(4):333-339
Current forensic DNA profiling methods rely on the analysis of samples at specialised laboratories with an average turnaround time of several days. The ability to rapidly determine a partial profile of short tandem repeats at the point-of-arrest would be of great benefit to police forces around the world, for example enabling a suspect to be rapidly included or excluded from an investigation. We have developed a homogeneous PCR method for the interrogation of STR loci utilising fluorescent oligonucleotide probes and melting curve analysis. Alleles of the D18S51, TH01 and D8S1179 loci were differentiated and identified on the basis of target length and probe melting temperature. Assay performance was evaluated by comparing melting peak data with the AmpFlSTR® SGM Plus® system. The method is compatible with direct analysis of unpurified buccal swab samples, enabling a partial STR profile to be generated within 1 h. 相似文献
926.
Correlation among age, concentrations of carboxyhemoglobin and hydrogen cyanide, oxygen density and hemolysis were studied in 120 house fire victims. Victims aged over 60 years comprised approximately 50% of the pooled subjects. Blood samples were mainly collected from the left ventricle, but sometimes from both the right and left ventricles. The concentration of carboxyhemoglobin ranged from 1-95%, of which 71 persons (59.7%) died with carboxyhemoglobin concentrations below 60%. Carboxyhemoglobin concentrations below 10% were found in 9 persons (7.5%). Most of these cases involved the elderly persons. In this paper, we report on the death of elderly victims as a result of low carboxyhemoglobin concentrations. A significant correlation of blood carboxyhemoglobin concentrations existed between the right and left ventricles. The concentration of carboxyhemoglobin in the left ventricle was significantly higher than that in the right. Two out of 31 victims whose hydrogen cyanide concentrations were determined, succumbed to hydrogen cyanide poisoning, having a high concentration of hydrogen cyanide and a low concentration of carboxyhemoglobin. On analysis, oxygen density was found to be low in 13 persons. A negative correlation was shown between carboxyhemoglobin concentration and hemolysis. Inasmuch as hemolysis may indicate the extent of heat dissociation, hemolysis should provide an index of carbon monoxide dissociation from carboxyhemoglobin. In the present study of victims, possible causes of death i.e., carbon monoxide gas poisoning, hydrogen cyanide poisoning, oxygen deprivation, burning, shock due to burns and others were estimated. The survival time for elderly victims was considered to be short. 相似文献
927.
928.
Our goal in this article is to contribute conceptually and empirically to assessments of the racial invariance hypothesis, which posits that structural disadvantage predicts violent crime in the same way for all racial and ethnic groups. Conceptually, we elucidate the scope of the racial invariance hypothesis and clarify the criteria used for evaluating it. Empirically, we use 1999–2001 averaged arrest data from California and New York to extend analyses of the invariance hypothesis within the context of the scope and definitional issues raised in our conceptual framing—most notably by including Hispanic comparisons with Blacks and Whites, by examining the invariance assumption for homicide as well as the violent crime index, by using discrete as well as composite disadvantage measures, and by using census place localities as the study unit. The mixed findings we report from our comparisons (across Whites, Blacks, and Hispanics; offense types; and type of disadvantage) suggest caution and uncertainty about the notion that structural sources of violence affect racial/ethnic groups in uniform ways. We conclude that the hypothesis should be regarded as provisional, and its scope remains to be established as to whether it applies only under narrow conditions or is a principle of general applicability. 相似文献
929.
930.