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951.
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Identification of Different Forms of Cocaine and Substances Used in Adulteration Using Near‐infrared Raman Spectroscopy and Infrared Absorption Spectroscopy 下载免费PDF全文
Ciro A. F. O. Penido M.Sc. Marcos Tadeu T. Pacheco Ph.D. Renato A. Zângaro Ph.D. Landulfo Silveira Ph.D. Jr. 《Journal of forensic sciences》2015,60(1):171-178
Identification of cocaine and subsequent quantification immediately after seizure are problems for the police in developing countries such as Brazil. This work proposes a comparison between the Raman and FT‐IR techniques as methods to identify cocaine, the adulterants used to increase volume, and possible degradation products in samples seized by the police. Near‐infrared Raman spectra (785 nm excitation, 10 sec exposure time) and FT‐IR‐ATR spectra were obtained from different samples of street cocaine and some substances commonly used as adulterants. Freebase powder, hydrochloride powder, and crack rock can be distinguished by both Raman and FT‐IR spectroscopies, revealing differences in their chemical structure. Most of the samples showed characteristic peaks of degradation products such as benzoylecgonine and benzoic acid, and some presented evidence of adulteration with aluminum sulfate and sodium carbonate. Raman spectroscopy is better than FT‐IR for identifying benzoic acid and inorganic adulterants in cocaine. 相似文献
953.
Forensic Use of A Subtropical Blowfly: The First Case Indicating Minimum Postmortem Interval (mPMI) in Southern Brazil and First Record of Sarconesia Chlorogaster from a Human Corpse 下载免费PDF全文
Karine P. Vairo M.Sc. Rodrigo C. Corrêa M.Sc. Melise C. Lecheta M.Sc. Maria F. Caneparo M.Sc. Kleber M. Mise Ph.D. Daniel Preti BSc. Claudio J.B. de Carvalho Ph.D. Lucia M. Almeida Ph.D. Mauricio O. Moura Ph.D. 《Journal of forensic sciences》2015,60(Z1):S257-S260
Southern Brazil is unique due to its subtropical climate. Here, we report on the first forensic entomology case and the first record of Sarconesia chlorogaster (Wiedemann) in a human corpse in this region. Flies' samples were collected from a body indoors at 20°C. Four species were found, but only Chrysomya albiceps (Wiedemann) and S. chlorogaster were used to estimate the minimum postmortem interval (mPMI). The mPMI was calculated using accumulated degree hour (ADH) and developmental time. The S. chlorogaster puparium collected was light in color, so we used an experiment to establish a more accurate estimate for time since initiation of pupation where we found full tanning after 3 h. Development of C. albiceps at 20°C to the end of the third instar is 7.4 days. The mPMI based on S. chlorogaster (developmental time until the third instar with no more than 3 h of pupae development) was 7.6 days. 相似文献
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A defining feature of the modern US Senate is obstruction. Almost all pieces of legislation considered in the Senate are affected either directly or indirectly by obstruction. Obstruction takes many forms in the modern Senate, but one of the most prevalent, yet least studied, is the hold. Using a newly created dataset on Republican Senate holds, we cast light on this important practice. Our results suggest that a variety of factors including timing, party status, and a senator's voting record are related to both the prevalence of holds and the success of legislation subject to holds in the Senate. 相似文献
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The extent to which assessment of personality disorders (PDs), and trans-diagnostic measures of PD severity, can capture the variance in psychopathy measured by the Psychopathy Checklist-Revised (PCL-R) was examined in 100 forensic patients with a history of violent offending. Correlational and linear regression analyses were carried out to establish whether (i) combinations of PDs would predict PCL-R scores for each of its two factors, interpersonal–affective (F1) and antisocial deviance (F2); (ii) ‘acting out’, a putative measure of externalising maladjustment that transcends PD categories, would predict PCL-R scores. Results showed that narcissistic and avoidant PDs contributed significantly to the prediction of F1, but only antisocial PD contributed to the prediction of F2. ‘Acting out’ predicted both F1 and F2, suggesting that core features of PCL-R psychopathy are embedded within and across different PD diagnoses. Results are discussed in relation to different sub-types of psychopathy described in the literature. 相似文献
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A recent article by Maxwell J. Mehlman and Tracy Yeheng Li, in the Journal of Law and the Biosciences, sought to examine the ethical, legal, social, and policy issues associated with the use of genetic screening and germ-line therapies (‘genomic technologies’) by the US Military. In this commentary, we will elaborate several related matters: the relationship between genetic and non-genetic screening methods, the history of selection processes and force strength, and the consequences and ethics of, as Mehlman and Li suggest, engineering enhanced soldiers. We contend, first, that the strengths of genomic testing as a method of determining enrollment in the armed forces has limited appeal, given the state of current selection methods in the US armed forces. Second, that the vagaries of genetic selection, much like other forms of selection that do not bear causally or reliably on soldier performance (such as race, gender, and sexuality), pose a systematic threat to force strength by limiting the (valuable) diversity of combat units. Third, that the idea of enhancing warfighters through germ-line interventions poses serious ethical issues in terms of the control and ownership of ‘enhancements’ when members separate from service. 相似文献
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Jill O. Robinson Melody J. Slashinski Elizabeth Chiao Amy L. McGuire 《Journal of Law and the Biosciences》2015,2(3):697-704
There is an urgent need for consistent data sharing policies that promote the advancement of science while respecting the values and interests of those providing their genetic data for research. Responding to the article of Jalayne J. Arias, Genevieve Pham-Kanter, and Eric G. Campbell, ‘The Growth and Gaps of Genetic Data Sharing Policies in the United States’, this commentary further explores the challenges of human subjects’ protection in existing data sharing policies. We will elaborate on the need for data sharing policies to accommodate variation in individual and group preferences around data sharing and privacy concerns by comparing our previously published data on patients’ and parents’ consent to data sharing and attitudes about privacy to data from focus groups with HIV-positive, underserved individuals who were asked about their willingness to participate in genetic research and share their data broadly. These studies support the observation of Arias, Pham-Kanter, and Campbell that researchers, and funding agencies will need to balance the privacy interests of groups as well as individuals in future genomic data sharing policies. 相似文献