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Panella M Koehler SA Shakir A Williams K 《The American journal of forensic medicine and pathology》2011,32(1):20-24
Hereditary hemochromatosis (HH) is one of the most common genetic disorders and may present clinically in a variety of ways. The most common presentation is micronodular cirrhosis with possible associated diabetes. However, HH may also present with cardiac dysfunction and sudden death. The confirmation of unsuspected HH at autopsy is complicated by the growing number of genetic abnormalities, which are not detected by current commercial genetic testing for C282Y and H63D mutations. Consequently, quantitative liver iron studies on fresh or paraffin embedded liver is recommended in confirming HH. The importance of detection and confirmation of HH cannot be overemphasized given the need to screen surviving family members in preventing organ damage of asymptomatic individuals. We present a case of a 38-year-old white woman with micronodular cirrhosis secondary to unsuspected HH that was confirmed by a quantitative liver iron study. The possible presentation of cardiac sudden death from HH, confirmation issues and implications of a HH diagnosis for surviving family members are also discussed. 相似文献
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Erin E. Waddell Ph.D. Mary R. Williams M.S. Michael E. Sigman Ph.D. 《Journal of forensic sciences》2014,59(4):927-935
A multistep classification scheme was used to detect and classify ignitable liquid residues in fire debris into the classes defined by the ASTM E1618‐10 standard method. The total ion spectra (TIS) of the samples were classified by soft independent modeling of class analogy (SIMCA) with cross‐validation and tested on fire debris. For detection of ignitable liquid residue, the true‐positive rate was 94.2% for cross‐validation and 79.1% for fire debris, with false‐positive rates of 5.1% and 8.9%, respectively. Evaluation of SIMCA classifications for fire debris relative to a reviewer's examination led to an increase in the true‐positive rate to 95.1%; however, the false‐positive rate also increased to 15.0%. The correct classification rates for assigning ignitable liquid residues into ASTM E1618‐10 classes were generally in the range of 80–90%, with the exception of gasoline samples, which were incorrectly classified as aromatic solvents following evaporative weathering in fire debris. 相似文献
806.
Shane Williams B.S. Shelby Hubbard B.S. Karl J. Reinhard Ph.D. Sergio Miranda Chaves Ph.D. 《Journal of forensic sciences》2014,59(6):1642-1649
Previous research into pollen content of tobacco resulted in a debate. We address this debate and determine that pollen analysis may be able to assist with identifying geographical origin of tobacco. However, the value of any results should be assessed on a case‐by‐case regional basis until sufficient database information is available for an objective interpretation to be undertaken on a global basis. As a first step toward developing comparative data for South America, we analyzed a tobacco sample from Brazil in an effort to identify signature taxa from the state of Minas Gerais. We also assessed the role of honey additives to tobacco to assess this issue. Comparing the data to previously published data, we conclude that pollen signatures can distinguish broad geographic areas. We conclude that this forensic interpretation framework needs to be developed in context of the National Academy of Sciences recommendations for tightening methods in forensic science. 相似文献
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Kumar J Landheer D Barnes-Warden J Fenne P Attridge A Williams MA 《Forensic science international》2012,214(1-3):48-58
Fundamental to any ballistic armour standard is the reference projectile that is to be defeated. Typically, for certification, consistency of bullets is assumed. Therefore, practical variations in bullet jacket dimensions can have far reaching consequences. Traditionally, internal dimensions could only be analysed by cutting bullets which rules out any subsequent ballistic assessment. Therefore, the use of a non-destructive X-ray computed tomography (CT) method is explored in this paper. A set of 10 bullets (9 mm DM11) was taken for analysing both intra and inter bullet jacket thickness variation. CT measurements of jacket thickness were validated with high resolution scanning electron microscope (SEM) images. An image based analysis methodology has been developed to extract the jacket thickness map and the centre of gravity. Thickness variations of the order of 200 μm were found commonly across all the bullets along the length and an angular variation of up to 100 μm was found in a few bullets. Jacket thickness and centre of gravity were also calculated for the same bullets after impact and the variations between the pre- and post-impacted bullets were compared, by establishing a common physical reference. The results show that the proposed CT scanning approach and subsequent image analysis method can bring out the statistical variations in bullet geometry pre- and post impact effectively. 相似文献
809.
The determination of line crossing sequences between rollerball pens and laser printers presents difficulties that may not be overcome using traditional techniques. This research aimed to study the potential of digital microscopy and 3-D laser profilometry to determine line crossing sequences between a toner and an aqueous ink line. Different paper types, rollerball pens, and writing pressure were tested. Correct opinions of the sequence were given for all case scenarios, using both techniques. When the toner was printed before the ink, a light reflection was observed in all crossing specimens, while this was never observed in the other sequence types. The 3-D laser profilometry, more time-consuming, presented the main advantage of providing quantitative results. The findings confirm the potential of the 3-D laser profilometry and demonstrate the efficiency of digital microscopy as a new technique for determining the sequence of line crossings involving rollerball pen ink and toner. 相似文献
810.
The withdrawal or withholding of life-sustaining treatment to compromised newborns is a subject of controversy in countries where there is now highly advanced neonatal care to keep such newborns alive. The topic has generated comparatively less debate in Australia, where case law is sparse and parents and clinicians themselves make decisions regarding the cessation of care, largely free from extemal oversight. The recent case of Re Baby D (No 2) [2011] FamCA 176 endorses this "closed" approach to neonatal decision-making. This article critically discusses some of its implications and makes suggestions for reform to ensure meaningful oversight of decisions to withdraw or withhold treatment. The authors argue that the judgment fails to address some fundamental issues, such as ensuring that those with the responsibility to make decisions are doing so on a "best interests" basis. This is important because, in a society where disability remains stigmatised and poorly understood, there is no opportunity under the approach adopted in Baby D to guarantee adequate protection of the rights of individuals born with physical or intellectual impairments. 相似文献