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821.
In the forensic context, teeth are often recovered in mass disasters, armed conflicts, and mass graves associated with human rights violations. Therefore, for victim identification, techniques utilizing the dentition to estimate the first parameters of identity (e.g., age) can be critical. This analysis was undertaken to apply a Bayesian statistical method, transition analysis, based on the Gompertz-Makeham (GM) hazard model, to estimate individual ages-at-death for Balkan populations utilizing dental wear. Dental wear phases were scored following Smith's eight-phase ordinal scoring method and chart. To estimate age, probability density functions for the posterior distributions of age for each tooth phase are calculated. Transition analysis was utilized to generate a mean age-of-transition from one dental wear phase to the next. The age estimates are based on the calculated age distribution from the GM hazard analysis and the ages-of-transition. To estimate the age-at-death for an individual, the highest posterior density region for each phase is calculated. By using a Bayesian statistical approach to estimate age, the population's age distribution is taken into account. Therefore, the age estimates are reliable for the Balkan populations, regardless of population or sex differences. The results showed that a vast amount of interpersonal variation in dental wear exists within the current sample and that this method may be most useful for classifying unknown individuals into broad age cohorts rather than small age ranges.  相似文献   
822.
The prime objective of this article is to construct a robust macroeconomic performance (MEP) index of the Indian economy using the data envelopment analysis (DEA) approach. Seven major macro indicators, namely, economic growth, employment rate, terms of trade, inflation rate, fiscal deficit, pollution, and climate change are used to compute MEP and Eco‐MEP indices of the Indian economy from 1980–1981 to 2018–2019. Overall, both the MEP and Eco‐MEP index scores have quite similar best performing years worst performing years, and have also captured the major events that affected adversely the Indian economy during the past decades. The trend in the overall performance of the Indian economy was better in the 1980s and the 1990s but has deteriorated since 2000. The autoregressive distributed lag bounds testing approaches to cointegration methods are used to test the robustness/utility of these indices. The estimated results show that MEP and Eco‐MEP have a positive impact on private investment, foreign investment inflows, foreign direct investment, and a negative effect on the current account deficit. Hence, the suggested composite MEP index is stable, robust and truly captures the economic performance of India. The constructed MEP composite index may be used by foreign investors, rating agencies, private investors, and policymakers for their planning and decision‐making processes.  相似文献   
823.
A solid-phase microextraction (SPME) procedure involving direct contact between the SPME fibers and the solid matrix and subsequent gas chromatography/mass spectrometric analysis for the detection of accelerants in fire debris is described. The extraction performances of six fibers (100 mum polydimethylsiloxane, 65 mum polydimethylsiloxane-divinylbenzene, 85 mum polyacrylate, 85 mum carboxen-polydimethylsiloxane, 70 mum Carbowax-divinylbenzene, and 50/30 mum divinylbenzene-Carboxen-polydimethylsiloxane) were investigated by directly immersing the fibers into gasoline, kerosene, and diesel fuel. For simulated fire debris, in the direct contact extraction method, the SPME fiber was kept in contact with the fire debris matrix during extraction by penetrating plastic bags wrapping the sample. This method gave comparable results to the headspace SPME method in the extraction of gasoline and kerosene, and gave an improved recovery of low-volatile components in the extraction of diesel fuel from fire debris. The results demonstrate that this procedure is suitable as a simple and rapid screening method for detecting ignitable liquids in fire debris packed in plastic bags.  相似文献   
824.
We reported two non-fatal cases of intoxication with pesticides namely alachlor and carbofuran. Hair stand samples were collected from two men approximately 1 year after alachlor intoxication for case 1, and 14 days after the last exposure for case 2. Hair analysis was performed using a liquid chromatography-tandem mass spectrometry method. In case 1, alachlor was detected in the 5 analysed hair segments (concentrations between 12 and 136 pg/mg) and its metabolites were not detected. In case 2, carbofuran and its main metabolite (3-hydroxycarbofuran) were detected in the hair strand (global analysis) at the concentrations of 207 and 164 pg/mg, respectively. However, additional data are required in order to interpret such results.  相似文献   
825.
The requirement to differentiate between incorporation and external contamination of drugs into hair is undisputed, in particular when dealing with compounds which are administered by sniffing or inhalation (e.g. cocaine). With the aim of making this discrimination, hair samples from cocaine (COC) users (group IN) and seized cocaine samples (group OUT) were compared regarding the parameters benzoylecgonine (BZE), ecgonine methyl ester (EME), ecgonine (ECG), anhydroecgonine methyl ester (AEME), cocaethylene (CE) and norcocaine (NCOC). Since most of these compounds may be minor by-products of COC or be formed by biotransformation or chemical degradation, the stability of each substance was carefully examined. COC was found to be converted into significant amounts of BZE, EME and ECG even under mild extraction conditions, while traces of NCOC proved to be a ubiquitous by-product of COC. Cocaine positive hairs and seized cocaine samples (diluted to relevant concentrations) were equally preprocessed and analyzed by LC-MS-MS. Out of the metabolites listed above, NCOC, CE and AEME (each normalised to COC) were significantly increased in the incorporation group (i.e. hair samples from cocaine users). Based on this approach, a statistical discriminant analysis enabled us to make a prediction (and estimation of uncertainty) for each cocaine positive hair sample as to its likelihood of belonging to the group of cocaine users or of being contaminated.  相似文献   
826.
模糊立法语言的语义学分析   总被引:1,自引:0,他引:1  
法律以语言文字为载体。尽管法律人竭力为法律概念设定边界,但是大部分法律概念的内涵或外延依然是模糊的。在法律的创制过程中,合理使用模糊语言不但不会损害法律的明确性,相反倒可能有助于在不确定中寻求到确定性。  相似文献   
827.
利用判别分析的方法,对200例上腭(石膏模型)的11项指标的性别进行性别研究,为用腭判定性别提供了依据,结果发现,有10个指标存在显著意义的性别差异(P<0.05)。应用判别分析方法,获得3个判别函数式,其判别率在64.00%~76.00%,本研究为用腭判定性别提供依据。  相似文献   
828.
体液中常见滥用药物的系统筛选分析   总被引:6,自引:1,他引:5  
本文建立了体液中常见滥用药物的筛选分析体系.尿液或血液经固相萃取(SPE)或液提取(LLE)后,直接用GC/NPD分析或经TFA、BSTFA衍生化后用GC/MS分析.方法适用于同时分析甲基苯丙胺、MDMA、度冷丁、去甲度冷丁、曲马多、美沙酮、EDDP、可卡因、苯甲酰芽子碱、可待因、安定、氯丙嗪、吗啡、单乙酰吗啡等十四种常见滥用药物及代谢物.SPE法和LLE法回收率分别为66~102%和50~86%,最低检出限为2-5ng/ml尿.涉毒案件的鉴定应用表明该分析方法简便、快速、可靠.  相似文献   
829.
In criminological studies of racial disparities the effect of race on outcomes is assessed after statistical controls for other variables. There is no universally accepted measure of size of disparity after controls in the most common type of disparity study: the study of binary outcomes. Some such studies use a measure that lends itself to interpretation in terms of the proportional reduction in error (PRE). Most use a non-PRE measure of association. This study investigates the effect of choice of measure on conclusions about the size of a disparity after controls. For illustrative purposes the study analyzes data on the awarding of sentence reductions to drug traffickers. After controls, blacks are found to be substantially less likely than whites to receive a reduction according to a type of non-PRE measure: an odds ratio derived from a logit model. But using the same data and model, PRE measures obtained from an ROC analysis indicate that, after controls, there is hardly any difference between the races in their likelihood of sentence reduction. Results illustrate the study's thesis: that the choice of measure can powerfully affect conclusions. The findings' implications—for policymakers and for researchers who conduct racial disparity studies—are discussed.  相似文献   
830.
This paper advances a hybrid police cost function that synthesises the proactive/preventive and response/reactive methodologies from the criminology literature. The model presents a coherent estimation process that can help in the allocation of scarce resources to police forces and also enable economists, government organisations and criminologists to assess the scale and technical efficiency of forces. This hybrid model uses response survey data for a sample of English and Welsh police forces in which relative efficiency rankings are contrasted with relative performance measures produced by the Audit Commission. We find that there are considerable divergences in police force's scale and technical efficiency during 1997/98 and 1998/99 utilising non-parametric techniques.  相似文献   
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