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A range of fibre samples was measured using J&M MSP400 and J&M MSP800 microspectrophotometers across the visible and UV/visible wavelength ranges respectively. The first derivative of the absorbance spectra was then calculated and studied. When the absorbance spectra produced for some samples were broad and featureless, the first derivative spectra provided more points of comparison that facilitated discrimination. For many of the samples, calculating the first derivative did not result in any additional discrimination due to the high number of points of comparison present in the absorbance spectra. However, for the samples that exhibited a high level of intra-sample colour variation (e.g. through uneven dye uptake common in cotton and wool, etc.), which was evident in the absorbance spectra, the associated first derivative spectra highlighted this variation between the fibres and could potentially have resulted in false exclusions. The results show that whilst calculating first derivative can be a useful aid in the comparison of spectra, a high degree of caution is required when applying this method to fibres which exhibit a large intra-sample variation in colour.  相似文献   
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In this research, Professor Jürgen Simon and Christian Ravenstein have highlighted the general existing prohibition, in the labour field, of the undertaking of genetic tests that could mean discrimination for the genetic heritage of the worker. They have made a comparative study of several member States of the EU that have specific regulation on this area.  相似文献   
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Human blood is the body fluid most commonly encountered at crime scenes, and blood detection may aid investigators in reconstructing what occurred during a crime. In addition, blood detection can help determine which items of evidence should be processed for DNA-STR testing. Unfortunately, many common substances can cause red-brown stains that resemble blood. Furthermore, many current human blood detection methods are presumptive and prone to false positive results. Here, the developmental validation of a new blood identification test, Rapid Stain Identification™-Blood (RSID™-Blood), is described. RSID™-Blood utilizes two anti-glycophorin A (red blood cell membrane specific protein) monoclonal antibodies in a lateral flow strip test format to detect human blood. We present evidence demonstrating that this test is accurate, reproducible, easy to use, and highly specific for human blood. Importantly, RSID™-Blood does not cross-react with ferret, skunk, or primate blood and exhibits no high-dose hook effect. Also, we describe studies on the sensitivity, body fluid specificity, and species specificity of RSID™-Blood. In addition, we show that the test can detect blood from a variety of forensic exhibits prior to processing for DNA-STR analysis. In conclusion, we suggest that RSID™-Blood is effective and useful for the detection of human blood on forensic exhibits, and offers improved blood detection when compared to other currently used methods.  相似文献   
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Sexing of human clavicles using length and circumference measurements   总被引:1,自引:0,他引:1  
Measurement of clavicular length and circumference, and computation of clavicular robustness and length-circumference product from 724 autopsied adults of known age, sex, and body length between the ages of 15 and 96 years produced useful sex-predictive values. This predominantly North American white population contained 560 males and 164 females with intact, nondeformed clavicles. Clavicle length and circumference and particularly their product have been found useful in sexing, but robustness as a single trait has not. Despite a significant overlap of male and female values, the use of single cutoff values allowed correct sex assignment of up to 93% of the entire study population, including 94% of males and 89% of females. The ratios of body length to clavicle circumference and to clavicle length are on average greater in women than in men. The former ratio yields male predictive values greater than 95% for those individuals with ratios falling below the cutoff value of 43, whereas the latter ratio is a relatively poor sex predictor.  相似文献   
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