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41.
An improved method for detecting diatom in blood is reported. Blood of cadavers was obtained by cardiac puncture at inquest or from the left atrium directly at autopsy. The blood was hemolyzed by sodium dodecyl sulfate (SDS) and filtered through membrane filter (47 mm in diameter and 5 microns in pore size). When the blood was putrefied, two or three pieces of membranes filters were needed because of choking membrane pore. The membrane filters were digested with fuming nitric acid and diluted with distilled water. The diluted solution was filtered through membrane filter (25 mm in diameter) again. After drying the membrane filter was immersed in oil. Diatoms on the membrane filter were clearly observed microscopically.  相似文献   
42.
High‐throughput sequencing (HTS) of large panels of single nucleotide polymorphisms (SNPs) provides an alternative or complimentary approach to short tandem repeats (STRs) panels for the analysis of complex DNA mixture forensic samples. For STRs, methods to estimate individual contribution concentrations compare capillary electrophoresis peak heights, peak areas, or HTS allele read counts within a mixture. This article introduces three approaches (mean, median, and slope methods) for estimating individual DNA contributions to forensic mixtures for HTS/massively parallel sequencing (MPS) SNP panels. For SNPs, the major:minor allele ratios or counts, unique to each contributor, were compared to estimate contributor proportion within the mixture using the mean, median, and slope intercept for these alleles. The estimates for these three methods were typically within 5% of planned experimental contributions for defined mixtures.  相似文献   
43.
The economic rise of the BRICS (Brazil, Russia, India, China and South Africa) inevitably leads to a redistribution of power in the international system. Chinese leaders today accord a considerable priority to this group, and there are elements of realism, liberalism/institutionalism and constructivism in their approach. This article intends to study China's policy towards BRICS and examine the above elements so as to better understand how the Chinese leadership perceives China's role in the international system, and how it seeks to articulate its interests and enhance its influence.  相似文献   
44.
Social Justice Research - Acting on one’s moral principles is not always easy. Upholding one’s moral beliefs may run counter to one’s social environment or situational demands. It...  相似文献   
45.
Postmortem computed tomography (PMCT) is integrated into the evaluation of decedents in several American medical examiner offices and medicolegal death investigative centers in many other countries. We retrospectively investigated the value of PMCT in a series of firearm homicide cases from a statewide centralized medical examiner’s office that occurred during 2016. Autopsies were performed or supervised by board-certified forensic pathologists who reviewed the PMCT scans prior to autopsy. PMCT scans were re-evaluated by a forensic radiologist blinded to the autopsy findings and scored by body region (head–neck, thoracoabdominal, and extremities). Injury discrepancies were scored using a modified Goldman classification and analyzed with McNemar’s test. We included 60 males and 20 females (median age 31 years, range 3–73). Based on PMCT, 56 (79.1%) cases had injuries relevant to the cause of death in a single body region (24 head–neck region, 32 thoracoabdominal region). Out of these 56 cases, 9 had a missed major diagnosis by PMCT outside that region, including 6 extremity injuries visible during standard external examination. Yet all had evident lethal firearm injury. We showed that PMCT identifies major firearm injuries in homicide victims and excludes injuries related to the cause of death in other regions when a single body region is injured. Although PMCT has a known limited sensitivity for soft tissue and vascular pathology, it can be combined with external examination to potentially reduce or focus dissections in some of these cases depending on the circumstances and medicolegal needs.  相似文献   
46.
Ammonium nitrate fuel oil is an explosive mixture found in most antipersonnel landmines (APL) buried throughout the Colombian territory. During more than 50 years of internal conflict, the Colombian government has found that trained dogs are the most effective method to detect APL. However, the olfactive signature in ANFO is unknown and also if there are differences in detection related to the explosive manufacturing origin. Therefore, this work begins with the analytical validation of the method used to determine ammonia, in its derivatized form as carbamate, released by home-made ANFO using HS-SPME-GC-FID. Once validated, the method was used to identify ammonia and other organic volatile compounds present in ANFO, under laboratory and simulated field conditions. The validation process includes the evaluation of the optimum conditions for the derivation and extraction of butylcarbamate, the determination of the working ranges with linear response in FID, the limits of detection and quantification, the sensitivity, and the precision. The results of the validation established linearity and sensitivity in a concentration between 20 and 120 mg/L, as well as low limits of detection and quantification of 6.4 and 21.4 mg/L, respectively. Also, an intermediate precision of 11% for butylcarbamate with a repeatability of 8%. The validated method showed in real samples of home-made ANFO besides ammonia, the presence of low molecular methylamines, and also exhibited differences in volatile compositions according to the origin. The objective of this work is to offer a reliable analytical methodology for the extraction and analysis of volatile compounds from ANFO.  相似文献   
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48.
Considerable research has focused on the reliability and validity of informant reports of family behavior, especially maternal reports of adolescent problem behavior. None of these studies, however, has based their orientation on a theoretical model of interpersonal perception. In this study we used the social relations model (SRM) to examine family members’ reports of each others’ externalizing and internalizing problem behavior. Two parents and two adolescents in 69 families rated each others’ behavior within a round-robin design. SRM analysis showed that within-family perceptions of externalizing and internalizing behaviors are consistently due to three sources of variance; perceiver, target, and family effects. A family/contextual effect on informant reports of problem behavior has not been previously reported.  相似文献   
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In what respects can military basic training affect veterans’ civic identities? According to a 2015 report published by the National Conference on Citizenship (NCoC), military service positively affects civic health. While social scientists have also noted this possible connection, little attention has been paid to how and why this link might exist. To test the purported relationship between military training and increased civic capacities, I explored the United States Marine Corps’ (USMC) Recruit Training program. I conducted 20 semi-structured, in-depth interviews with 17 enlisted Marine veterans and Marine drill instructors (DI) to ascertain their perceptions of the pedagogical aspirations of their service’s recruit training. The study’s participants reported that Marine Corps Recruit Training does seek to inculcate skills, values, and habits that are consistent with a civic identity as discussed in the civic-engagement and civic-education literature.  相似文献   
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