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371.
This review brings together a complex and extensive literature to address the question of whether it is possible to distinguish human from nonhuman bone using the histological appearance of cortical bone. The mammalian species included are rat, hare, badger, racoon dog, cat, dog, pig, cow, goat, sheep, deer, horse, water buffalo, bear, nonhuman primates, and human and are therefore not exhaustive, but cover those mammals that may contribute to a North American or Eurasian forensic assemblage. The review has demonstrated that differentiation of human from certain nonhuman species is possible, including small mammals exhibiting Haversian bone tissue and large mammals exhibiting plexiform bone tissue. Pig, cow, goat, sheep, horse, and water buffalo exhibit both plexiform and Haversian bone tissue and where only Haversian bone tissue exists in bone fragments, differentiation of these species from humans is not possible. Other primate Haversian bone tissue is also not distinguishable from humans. Where differentiation using Haversian bone tissue is undertaken, both the general microstructural appearance and measurements of histological structures should be applied. Haversian system diameter and Haversian canal diameter are the most optimal and diagnostic measurements to use. Haversian system density may be usefully applied to provide an upper and lower limit for humans. 相似文献
372.
Bell SE Fido LA Sirimuthu NM Speers SJ Peters KL Cosbey SH 《Journal of forensic sciences》2007,52(5):1063-1067
2,5,-Dimethoxy-4-bromoamphetamine (DOB) is of particular interest among the various "ecstasy" variants because there is an unusually long delay between consumption and effect, which dramatically increases the danger of accidental overdose in users. Screening for DOB in tablets is problematic because it is pharmacologically active at 0.2-3 mg, which is c. 50 times less than 3,4-methylenedioxy-N-methylamphetamine (MDMA) and makes it more difficult to detect in seized tablets using conventional spot tests. The normal Raman spectra of seized DOB tablets are dominated by the bands of the excipient with no evidence of the drug component. Here we report the first use of on-tablet surface-enhanced Raman spectroscopy (SERS) to enhance the signal from a low concentration drug. Raman studies (785-nm excitation) were carried on series of model DOB/lactose tablets (total mass c. 400 mg) containing between 1 mg and 15 microg of DOB and on seized DOB tablets. To generate surface-enhanced spectra, 5 microL of centrifuged silver colloid was dispensed onto the upper surface of the tablets, followed by 5 microL of 1.0 mol/dm(3) NaCl. The probe laser was directed onto the treated area and spectra accumulated for c. 20 sec (10 sec x 2). It was found that the enhancement of the DOB component in the model tablets containing 1 mg DOB/tablet and in the seized tablets tested was so large that their spectra were completely dominated by the vibrational bands of DOB with little or no contribution from the unenhanced lactose excipient. Indeed, the most intense DOB band was visible even in tablets containing just 15 microg of the drug. On-tablet surface-enhanced Raman spectroscopy is a simple method to distinguish between low dose DOB tablets and those with no active constituent. The fact that unique spectra are obtained allows identification of the drug while the lack of sample preparation and short signal accumulation times mean that the entire test can be carried out in <1 min. 相似文献
373.
目的探讨撕脱性骨折与永存性骨骺、籽骨、副骨的影像学鉴别办法。方法回顾性分析了14个要求重新鉴定是否存在骨折的案例,观察撕脱性骨折的直接、间接征象,并结合其发生机制与永存性骨骺、籽骨及副骨的固有形态、特点等进行对照。结果所选案例中有2例永存性骨骺、3例籽骨、3例副骨均具有骨块边缘钝圆、骨皮质连续、局部软组织未见肿胀以及伤后该骨的连续摄片无明显变化等共同特征。结论正确掌握撕脱性骨折、生理性小骨骺、籽骨及解剖变异的副骨的特点,并综合运用影像学资料是鉴别撕脱性骨折的基本要素。 相似文献
374.
375.
整体性治理对我国海洋环境管理体制改革的启示 总被引:8,自引:0,他引:8
我国海洋环境管理体制虽经历了多次变革,但由于种种原因,现行的海洋环境管理体制至今还是分散型的。这种分散型管理体制存在诸多弊端,难以适应世界海洋环境管理一体化发展的趋势。本文借鉴西方整体性治理理论,对我国现行海洋环境管理体制现状及存在的问题进行客观的梳理和分析,探讨了今后我国海洋环境管理体制改革的方向,并对今后我国海洋环境治理模式进行了初步构想。 相似文献
376.
Moses RJ 《Journal of forensic sciences》2012,57(3):589-595
Adipocere, or grave wax (adipo = fat, cere = wax), is a distinctive decomposition product composed primarily of fatty acids (FA) and their alkali salts. FA result from the bacterial enzymatic hydrolysis of body fats. Reactions with ammonia and alkali metals originating from body fluids and pore waters of the depositional environment produce alkali salts of FA (soap). Adipocere formation is generally associated with burial of corpses with ample adipose tissue available. No indications that adipocere can form on defleshed remains have been presented in the literature. At the termination of a long-term bone diagenesis experiment, several samples were found to possess growths of an unknown compound. Gas chromatography-mass spectrometry confirmed that the growths are adipocere. The results herein reveal that adipocere can indeed form on defleshed bones under the right conditions and that even residual adipose and lipids in defleshed bones are sufficient to produce adipocere growth on the surfaces of bone. 相似文献
377.
Peter Kabachnik 《Central Asian Survey》2012,31(1):45-60
This paper examines the role of territorial integrity narratives in the Republic of Georgia, which currently features two separatist territories – Abkhazia and South Ossetia – which are de facto independent and have begun to receive limited international recognition. Political rhetoric is further buttressed by various government policies and practices that help transmit the message of territorial integrity to the Georgian public. Cartographic anxieties, or the preoccupation and fear of a country's loss of territory, is a central feature of Georgian nationalist discourse. Referring to the loss of territory as amputation exemplifies the cartographic anxieties displayed in Georgia. Specifically, I will focus on the role of political discourse, maps, patriotic youth camps and billboards and other elements of the landscape, documenting how they help to reproduce the discourse of territorial integrity. It is precisely these discourses and practices that reproduce territorial integrity narratives and construct the entire Georgian territory (including Abkhazia and South Ossetia) as integral to Georgian national identity, enabling the separatist regions to be understood as wounds that won't heal. 相似文献
378.
Skeletal remains of a domestic pig were assessed for relative distribution of amitriptyline, citalopram, and metabolites. Following acute exposure and outdoor decomposition for 2 years, drugs and metabolites were analyzed in 13 different bones. Bones were pulverized following a simple wash procedure, and drugs were extracted by passive incubation in methanol, followed by solid-phase extraction. Samples were analyzed by ultra-high performance liquid chromatography (UHPLC) and confirmed with gas chromatography-mass spectrometry. The Kruskall-Wallis test showed that bone type was a main effect with respect to drug level for all analytes, with levels varying from 33- to 166-fold. Ratios of levels of drug to that of the corresponding metabolite were less variable, varying roughly one- to eightfold. This suggests limitations in the interpretive value of drug measurements in bone and that relative levels of drug and metabolites should be further investigated in terms of forensic value. 相似文献
379.
目的比较有机法+QIAquick纯化法和DNA IQ磁珠法对陈旧骨骼和牙齿DNA的纯化效果。方法选择10份陈旧骨骼和12份牙齿样本,进行消化后分别采用有机法+QIAquick纯化法和DNA IQ磁珠法进行提取纯化,进行DNA定量后用SinofilerTM试剂盒进行检测。结果 2种方法纯化的骨骼、牙齿DNA的IPC CT值无显著差异。有机法+QIAquick纯化法纯化的骨骼、牙齿DNA平均浓度分别为0.180ng/μL±0.068ng/μL和0.132ng/μL±0.027ng/μL,所有样品均获得全部基因分型。DNA IQ磁珠法纯化的DNA平均浓度分别为0.038ng/μL±0.028ng/μL和0.036ng/μL±0.007ng/μL,有5份骨骼和6份牙齿样本仅获得部分基因分型或未能分型。结论有机法+QIAquick纯化法对陈旧骨骼、牙齿DNA的纯化效果优于DNA IQ磁珠法。 相似文献
380.
Steven J. Walden M.Sc. Jacqui Mulville Ph.D. Jeffrey P. Rowlands H.N.D. Sam L. Evans Ph.D. 《Journal of forensic sciences》2018,63(1):207-213
The aim of this pilot study was to investigate compositional changes in bone during decomposition. Elemental concentrations of barium, calcium, iron, potassium, magnesium, zinc and phosphorus in porcine bone (as an experimental analog for human bone) were analyzed by inductively coupled plasma optical emission spectroscopy (ICP‐OES). The samples were taken from porcine bone subjected to shallow burial and surface depositions at 28‐day intervals for a period of 140 days. Results indicated that ICP‐OES elemental profiling has potential to be developed as a forensic test for determining whether a bone sample originates from the early stages of soft tissue putrefaction. Significant changes in iron, sodium and potassium concentrations were found over 140 days. These elements are known to be primarily associated with proteins and/or tissue fluids within the bone. Changes in their respective concentrations may therefore be linked to dehydration over time and in turn may be indicative of time since deposition. 相似文献