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91.
The identification of human bodies in situations when there are no clues as to the person's identity from circumstantial data, poses a difficult problem to the investigators. The determination of age and sex of the body can be crucial in order to limit the search to individuals that are a possible match. We analyzed the proportion of bomb pulse derived carbon-14 ((14)C) incorporated in the enamel of teeth from individuals from different geographical locations. The 'bomb pulse' refers to a significant increase in (14)C levels in the atmosphere caused by above ground test detonations of nuclear weapons during the cold war (1955-1963). By comparing (14)C levels in enamel with (14)C atmospheric levels systematically recorded over time, high precision birth dating of modern biological material is possible. Above ground nuclear bomb testing was largely restricted to a couple of locations in the northern hemisphere, producing differences in atmospheric (14)C levels at various geographical regions, particularly in the early phase. Therefore, we examined the precision of (14)C birth dating of enamel as a function of time of formation and geographical location. We also investigated the use of the stable isotope (13)C as an indicator of geographical origin of an individual. Dental enamel was isolated from 95 teeth extracted from 84 individuals to study the precision of the (14)C method along the bomb spike. For teeth formed before 1955 (N=17), all but one tooth showed negative Δ(14)C values. Analysis of enamel from teeth formed during the rising part of the bomb-spike (1955-1963, N=12) and after the peak (>1963, N=66) resulted in an average absolute date of birth estimation error of 1.9±1.4 and 1.3±1.0 years, respectively. Geographical location of an individual had no adverse effect on the precision of year of birth estimation using radiocarbon dating. In 46 teeth, measurement of (13)C was also performed. Scandinavian teeth showed a substantially greater depression in average δ(13)C (-14.8) than teeth from subjects raised in Japan (-13.5), Middle East and North Africa (-12.7) and South America (-10.9). In summary, isotopic analysis of carbon in enamel from a single tooth can give a good estimate of the year of birth of an individual and also provide information about the geographical origin of the individual. This strategy can assist police and forensic authorities when attempting to solve unidentified homicide cases and may facilitate the identification work associated with mass disasters.  相似文献   
92.
The third molar tooth is one of the few anatomical sites available for age estimation of unknown age individuals in the late adolescent years. Computed tomography (CT) images were assessed in an Australian population aged from 15 to 25 years for development trends, particularly concerning age estimation at the child/adult transition point of 18 years. The CT images were also compared to conventional radiographs to assess the developmental scoring agreement between the two and it was found that agreement of Demirjian scores between the two imaging modalities was excellent. The relatively wide age ranges (mean ± 2SD) indicate that the third molar is not a precise tool for age estimation (age ranges of 3-8 years) but is, however, a useful tool for discriminating the adult/child transition age of 18 years. In the current study 100% of females and 96% of males with completed roots were over 18 years of age.  相似文献   
93.
ARPA-E offers a new innovation institutional model to meet energy technology challenges. Because it is explicitly based on DARPA, this article reviews the noted DARPA approach in detail. Briefly citing well-known features of DARPA, it explores a number of important features that have not been well discussed in the policy literature on DARPA. These include DARPA??s ability to undertake multigenerational technology thrusts, the synergies it has been able to create through complementary strategic technologies, its ability to build an advocate community, and connections it has built to larger innovation elements downstream from DARPA. It has also taken on incumbent technologies within both DOD and in the private sector, used ties to DOD leadership to press its advances, and supported initial market creation. The article then reviews the new ARPA-E model in detail, commenting first on how ARPA-E has adopted key DARPA approaches. It then discusses new features ARPA-E is adopting, driven by the unique demands of the complex, established energy sector. These include new ways: (1) to sharpen the research visioning, selection and support processes, (2) to build a community of support, important to its political survival, and (3) to implement technologies it supports. In addition, the further DARPA features enumerated above provide potentially useful future guideposts to ARPA-E. The paper closes with a discussion of the difficult technology implementation problems on the ??back end?? of the innovation system??including demonstrations, test beds, and initial markets. The article posits that both agencies must further address these implementation issues by fostering additional downstream partnerships, including between government and private sector.  相似文献   
94.
Background. There have been a number of developments in the assessment of dynamic risk in the criminological literature. The dynamic risk assessment and management system (DRAMS) has been developed to facilitate the measurement of dynamic factors of risk for offenders with intellectual disability. Method. The study was designed to assess the construct validity, reliability and predictive utility of the DRAMS in 23 male forensic patients in a high secure setting. Predictions were made against independently collected incident data. Concurrent validity was assessed against the Ward Anger Rating Scale (WARS). Results. A reformulation of the individual section variables according to convergent and discriminant correlational analysis revealed Cronbach's alpha levels of >.8 for all sections apart from mood (alpha .750) and items retained to facilitate clinical information (alpha ?.017). Two hundred pairs of WARS and DRAMS assessments revealed orderly sectional correlations. The sections of mood, antisocial behaviour, and intolerance/agreeableness predicted incidents with a medium effect size as did total DRAMS score. There were highly significant differences between assessments taken 1 or 2 days prior to an incident and control assessments conducted at least 7 days from an incident. Conclusions. The reformulated DRAMS has good construct and concurrent validity. It appears to be a reliable assessment tool and informs on risk levels relating to stable and acute proximal factors. It appears as an important addition to the utility of risk assessments for this population.  相似文献   
95.
Abstract: Stalking behavior and victim–stalker relationship are often the principal known factors in a stalking case. Thus, they are of great importance when trying to identify factors contributing to stalking duration. The present study aims to identify distinct subgroups of stalking victims based on measures of behavioral stalking dimensions. These victim subgroups, stalking dimensions, and victim–stalker relationship are examined in relation to stalking duration. Using a sample of 137 university students, latent profile analysis (LPA) revealed five distinct victim subgroups based on stalker behavior dimensions: surveillance, low‐profile, social lurker, wide scope, and baseline stalkers. The subgroups were significantly related to stalking duration and explained a considerable amount of the variance along with the stalking dimensions and victim–stalker relationship. Connections to stalking literature and utility of person‐orientated methods in stalking research are discussed.  相似文献   
96.
Abstract: The proper identification of illicit plants such as Papaver somniferum L (opium poppy) is important for law enforcement agencies. The identification of opium poppy was presently tested using 10 genetic markers that are universal for all plants or specific to a few poppy plants. The genetic distances of universal markers such as nuclear internal transcribed spacer (ITS), 18S rRNA, plastid rbcL, and trnL‐trnF intergenic spacer (IGS) of 14 species included in the Papaveraceae and Fumariaceae family were acquired by sequence comparisons. Both the ITS region and trnL‐trnF IGS showed high levels of interspecific divergence. Six Papaver genera‐specific markers were developed from coding regions involved in morphine biosynthesis. Three markers (TYDC, NCS, and BBE) produced amplicons only in opium poppy, providing a presence/absence test for opium poppy, while three additional markers (CYP80B1, SAT, and COR) were genus specific. These 10 markers might be useful for the forensic DNA analysis of opium poppy.  相似文献   
97.
Abstract: We tested the hypotheses that foraging insects can acquire human DNA from the environment and that insect‐delivered human DNA is of sufficient quantity and quality to permit standard forensic analyses. Houseflies, German cockroaches, and camel crickets were exposed to dusty surfaces and then assayed for human mitochondrial and nuclear loci by conventional and qPCR, and multiplex STR amplification. Over two experiments, 100% of insect groups and 94% of dust controls tested positive for human DNA. Of 177 individuals, 33–67% tested positive and 13 yielded quantifiable human DNA (mean = 0.022 ± 0.006 ng; mean dust control = 2.448 ± 0.960 ng); four had at least one positive allele call for one or more locus; eight others showed multiple peaks at some loci. Results imply that application to routine forensic casework is limited given current detection methodology yet demonstrate the potential use of insects as environmental samplers for human DNA.  相似文献   
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The Equal Employment Opportunity Commission (EEOC) recently issued its final regulations on the Americans with Disabilities Act (ADA). Although the regulations offer some guidance for employers on how to comply with the Act, they fail to provide specific answers to the many complicated compliance questions that will surely arise. Further, the regulations are almost totally silent on certain critical issues related to insurance, workers' compensation, and potential conflicts between ADA obligations and terms of collective bargaining agreements. The EEOC has essentially left the resolution of many important ADA questions to case-by-case determination and the litigation process.  相似文献   
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