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The forensic pathologist increasingly relies on the forensic anthropologist to be the consulting expert in human identification. Likewise, if identification is not possible from visual inspection of skeletal remains, the forensic biologist may be called upon to conduct DNA analysis. The possibility of downstream DNA testing needs to be considered when skeletal preparation techniques are employed to deflesh human remains, as they have the potential to strongly impact genetic analyses and subsequent identification. In this study, three cleaning techniques, boiling bone in water, in bleach, and in powdered detergent/sodium carbonate, were tested for their effect on nuclear and mtDNA recovery from a variety of human and non-human bones. A statistically significant reduction in DNA yields occurred in non-human bones cleaned with bleach, and DNA degradation was apparent electrophoretically. The human bones also showed much lower yields from bleach cleaning, while the detergent/carbonate method allowed the largest segments of DNA to be amplified, indicating it may have a less degradative effect on bone DNA than either of the other cleaning processes. 相似文献
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Despite recent and growing media attention surrounding obesity in the United States, the so-called obesity epidemic remains a highly contested scientific and social fact. This article examines the contemporary obesity debate through systematic examination of the claims and claimants involved in the controversy. We argue that four primary groups-antiobesity researchers, antiobesity activists, fat acceptance researchers, and fat acceptance activists-are at the forefront of this controversy and that these groups are fundamentally engaged in framing contests over the nature and consequences of excess body weight. While members of the fat acceptance groups embrace a body diversity frame, presenting fatness as a natural and largely inevitable form of diversity, members of the antiobesity camp frame higher weights as risky behavior akin to smoking, implying that body weight is under personal control and that people have a moral and medical responsibility to manage their weight. Both groups sometimes frame obesity as an illness, which limits blame by suggesting that weight is biologically or genetically determined but simultaneously stigmatizes fat bodies as diseased. While the antiobesity camp frames obesity as an epidemic to increase public attention, fat acceptance activists argue that concern over obesity is distracting attention from a host of more important health issues for fat Americans. We examine the strategies claimants use to establish their own credibility or discredit their opponents, and explain how the fat acceptance movement has exploited structural opportunities and cultural resources created by AIDS activism and feminism to wield some influence over U.S. public health approaches. We conclude that notions of morality play a central role in the controversy over obesity, as in many medical disputes, and illustrate how medical arguments about body weight can be used to stymie rights claims and justify morality-based fears. 相似文献
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In pursuing their goals, members of the U.S. Supreme Court areaffected by their institutional setting. How has that institutionalenvironment changed over time and what have been the politicalconsequences of those changes? Despite considerable analysisof the institutional dynamics of legislatures and executives,political scientists have been slow to bring time series techniquesto the study of the Supreme Court, and as a result much lessis known about its evolutionary path. Measuring a variety oforganizational characteristics, I construct an index of theinstitutionalization of the Supreme Court from 1790 to 1996.This indicator suggests that the integration of the Court intothe system of federal policy making has better enabled the justicesto satisfy their objectives. To demonstrate this empirically,I test a series of error correction models of judicial influence,each of which confirms that the nature of the Supreme Court'scharacter has had considerable implications for the scope ofthe justices' legal and political impact. These results underscorethe need for judicial scholars to examine the Court's policymaking in longitudinal perspective. 相似文献
78.
The purpose of this study was to evaluate the ability of two amphetamine class screening reagents to exclude ephedrine (EPH), pseudoephedrine (PSEPH), and phenylpropanolamine (PPA) from falsely producing positive immunoassay screening results. The study also sought to characterize the prevalence and concentration distributions of EPH, PSEPH, and PPA in samples that produced positive amphetamine screening results. Approximately 27,400 randomly collected human urine samples from Navy and Marine Corps members were simultaneously screened for amphetamines using the DRI and Abuscreen online immunoassays at a cutoff concentration of 500 ng/mL. All samples that screened positive were confirmed for amphetamine (AMP), methamphetamine (MTH), 3,4-Methylenedioxyamphetamine (MDA), 3,4-Methylenedioxymethamphetamine (MDMA), EPH, PSEPH, and PPA by gas chromatography/mass spectrometry (GC/MS). The DRI AMP immunoassay identified 1,104 presumptive amphetamine positive samples, of which only 1.99% confirmed positive for the presence of AMP, MTH, MDA, or MDMA. In contrast, the online AMP reagent identified 317 presumptive amphetamine positives with a confirmation rate for AMP, MTH, MDA, or MDMA of 7.94%. The presence of EPH, PSEPH, or PPA was confirmed in 833 of the 1,104 samples that failed to confirm positive for AMP, MTH, MDA, or MDMA; all of the 833 samples contained PSEPH. When compared to the entire screened sample set, PSEPH was present in approximately 3%, EPH in 0.9%, and PPA in 0.8% of the samples. The results indicate that cross reactivities for EPH, PSEPH, and PPA are greater than reported by the manufacturer of these reagents. The distribution of concentrations indicates that very large concentrations of EPH, PSEPH, and PPA are common. 相似文献
79.
Koehler SA Luckasevic TM Rozin L Shakir A Ladham S Omalu B Dominick J Wecht CH 《Journal of forensic sciences》2004,49(2):345-350
Each year over 3 million new chainsaws are sold in the United States. The operation of these newer saws combined with the millions of older chainsaws in circulation results in over 28,000 chainsaw-related injures annually. The majority of the injuries involve the hands and lower extremities with less than 10% involving injuries to the head and neck regions. Deaths while operating a chainsaw are extremely rare. The most common hazards associated with chainsaws are injuries caused by kickback, pushback, and pull-in. Kickback is the most common and poses the greatest hazard. Kickback occurs when the rotating chain is stopped suddenly by contact with a more solid area throwing the saw rapidly backward toward the operator. The cause of most injuries can be traced to improper use of the saw or poor judgment on part of the operator. We present two fatal chainsaw deaths; one with an older style saw, and the other with a modern type. In both cases the victims died from fatal injuries received to the neck region from a chainsaw kickback. The first case involved a 49-year-old white male operating an older style chainsaw with limited safety features. The second case involved a 38-year old white male who was operating a newer model chainsaw equipped with a low kickback chain in an unsafe manner. 相似文献
80.
Accident investigation is frequently cited as the cornerstone of an effective occupational health and safety program. We suggest that the literature on accident investigation is based on a model of witnesses as neutral and accurate recording devices. The literature on eyewitness testimony and criminal investigation offers strikingly different conclusions. We review these findings and point to their implication for research on accident investigation in occupational health and safety contexts. 相似文献