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831.
Following the September 11, 2001 terrorist attacks, letters containing Bacillus anthracis were distributed through the United States postal system killing five people. A complex forensic investigation commenced to identify the perpetrator of these mailings. A novel liquid chromatography/mass spectrometry protocol for the qualitative detection of trace levels of meglumine and diatrizoate in dried spore preparations of B. anthracis was developed. Meglumine and diatrizoate are components of radiographic imaging products that have been used to purify bacterial spores. Two separate chromatographic assays using multiple mass spectrometric analyses were developed for the detection of meglumine and diatrizoate. The assays achieved limits of detection for meglumine and diatrizoate of 1.00 and 10.0 ng/mL, respectively. Bacillus cereus T strain spores were effectively used as a surrogate for B. anthracis spores during method development and validation. This protocol was successfully applied to limited evidentiary B. anthracis spore material, providing probative information to the investigators.  相似文献   
832.
In Europe, authorities frequently ask forensic laboratories to analyze seized cannabis plants to prove that cultivation was illegal (drug type and not fiber type). This is generally done with mature and flowering plants. However, authorities are often confronted with very young specimens. The aim of our study was to evaluate when the chemotype of cannabis plantlets can be surely determined through analysis of eight major cannabinoids content during growth. Drug-type seedlings and cuttings were cultivated, sampled each week, and analyzed by high-performance liquid chromatography with diode array detection. The chemotype of clones was recognizable at any developmental stage because of high total Δ(9)-tetrahydrocannabinol (THC) concentrations even at the start of the cultivation. Conversely, right after germination seedlings contained a low total THC content, but it increased quickly with plant age up, allowing chemotype determination after 3 weeks. In conclusion, it is not necessary to wait for plants' flowering to identify drug-type cannabis generally cultivated in Europe.  相似文献   
833.
The authors present the case of a 14-year-old boy who died while handling a crossbow, which was a gift from a friend's mother. The bolt passed through the right nostril, penetrated the sinus sphenoidalis, the brain stem, the left occipital lobe and the occipital calvaria. Immediately after the accident, the victim was taken to a maximum care hospital. In spite of neurosurgical treatment and intensive care the victim died 4 days later. The case presented demonstrates that crossbows are not suitable as toys for underage persons, as they are deadly weapons which can cause serious penetrating injuries. In Germany, no license is required to buy and/or possess crossbows. In the authors' opinion, legal restrictions on the sale of crossbows and a special training of the users would be reasonable measures to reduce such accidents.  相似文献   
834.
The intervertebral haemorrhages described by Simon in 1968 as a vital sign of hanging have been verified and endorsed by other authors. They occur in 40-50 % of hanging cases, most frequently in the lumbar spine, in younger age groups, and in cases of free suspension. The haemorrhages are not unique to hanging, but may occur in particular as a result of other traumatic elongation or overextension of the spinal column (e. g. in the course of traffic accidents). In cases of decomposition of the body, "false positive" findings are relatively common. As external findings scarcely provide any reliable vital signs of hanging, there is still a high demand for autopsies. In addition to Simon's bleedings, internal findings which are diagnostically conclusive also include microscopic examinations of the lungs and the neck musculature. More recent findings such as haemorrhages in the back and auxiliary respiratory muscles as well as the intestinal wall, if confirmed, could supplement Simon's bleedings. Frei's fibre sample and evidence of histamine in the ligature mark should not be neglected. Finally, it must be emphasized that the forensic assessment of hanging cases should always be based on a criminological and forensic evaluation of all the circumstances of the offence as well as on post-mortem findings.  相似文献   
835.
The external post-mortem examination, its deficient quality and possible causes have been the subject of numerous political and professional discussions. The external post-mortem examination is the basis for the decision whether further criminal investigations are required to clarify the cause of death. It is thus an essential instrument to ensure legal certainty. Before cremation, a second external post-mortem examination is performed by a public medical officer to make sure that errors of the first post-mortem are corrected. In the present study, cases were retrospectively analyzed in which a forensic autopsy had been ordered on the basis of the results of the post-mortem examination performed before cremation. The entries on the death certificate regarding the manner and cause of death were compared with the autopsy results. Between 1998 and 2007, 387 autopsies were ordered after external examination before cremation. In 55 cases (14.2%), the autopsy revealed a non-natural death, although a natural death had been attested on the death certificate. In descending order, a wrong manner of death was attested by clinicians, general practitioners and emergency physicians. With regard to the place where the first external post-mortem had been performed the lowest error rate was seen in nursing homes. Concerning the cause of death, discrepancies between the first post-mortem and autopsy were found in 59.4% of the cases. In this respect, general practitioners and clinicians were ranking first, whereas in nursing homes the cause of death was wrongly assessed in over 70% of cases. At present, the medical post-mortem does not meet the required quality standards, especially with regard to legal certainty. Determination of the cause of death on the basis of the external post-mortem examination is a challenging task even for the experienced medical examiner. As to the categorization of the manner of death it has to be stated that non-natural deaths are often not recognized or that the possibility to certify a death as unclear is not sufficiently used. As a result, it seems important to demand intensive, qualified, additional training in external post-mortem examinations for physicians.  相似文献   
836.
Situating events and traces in time is an essential problem in investigations. To date, among the typical questions issued in forensic science, time has generally been unexplored. The reason for this can be traced to the complexity of the overall problem, addressed by several scientists in very limited projects usually stimulated by a specific case. Considering that such issues are recurrent and transcending the treatment of each trace separately, the formalisation of a framework to address dating issues in criminal investigation is undeniably needed. Through an iterative process consisting of extracting recurrent aspects discovered from the study of problems encountered by practitioners and reported in the literature, common mechanisms were extracted and provide understanding of underlying factors encountered in forensic practise. Three complementary approaches are thus highlighted and described to formalise a preliminary framework that can be applied for the dating of traces, objects, persons and indirectly events.  相似文献   
837.
A number of dyed acrylic and acetate fibre samples were examined with plane polarized light on their dichroic behavior by optical light microscopy (OLM) and microspectrophotometry with plane polarized light (MSP-PPL). It was found that most of these low birefringent fibres possess weak dichroic effects that are very hard to observe with microscopy. However, using MSP-PPL, the linear dichroism could be measured. A comparison between the dichroic effects found for the same disperse dyes on triacetate (TrAc), diacetate (Ac), polyester (PES) and polyamide (PA) shows that the linear dichroism follows the order: PA>PES >TrAc, Ac.  相似文献   
838.
The transformation of umbilical cord blood from being a waste product to being a valuable source of stem cells has led to the emergence of significant legal, ethical and social issues. This editorial proposes an agenda for research into the regulation of umbilical cord blood banking which focuses on issues of characterisation, consent, the interplay of public and private services, and the importance of applying property concepts. It concludes by stressing the need for reform to be based on well-informed public debate.  相似文献   
839.
俄罗斯现有的政治体制是"普京方案",专注于"内部改革",兼顾社会各种利益、问题和挑战,扮演着稳定局面的"保障者"和"危机管理人"的角色,但正在被社会大众所厌倦。因此,普京必须回归"战略管理者"的地位。然而,留给俄罗斯执政精英们用于决定转变的时间越来越少了。因此,当前亟须找到一种政治方略,确保"俄罗斯体系"不再经历新一轮的灾难和破坏性威胁。在此基础上建立社会和国家的"动态平衡"模式,这是俄罗斯历届领导人尚未完成的使命。只有实现国家现代化,重建社会、政治、经济和意识形态模式,使俄罗斯人获得政治民主地位,才是对于当代挑战的回答,其他任何方案都意味着历史悠久的俄罗斯将最终走向衰败和解体。  相似文献   
840.
Palatal rugae have been related with specific racial groups and are said to be useful in sex discrimination. This work aimed to characterize the palatal rugae patterns in a Portuguese population. Fifty plaster casts were examined for first and third rugae shape evaluation; shape, frequency, and association with sex were studied. In females, the most prevalent first rugae were the straight type on the right and the curve type on the left; in males, the straight type was the most prevalent on both sides. The most frequent third rugae type was sinuous on both sides, in both sexes. No significant sexual dimorphism in rugae shape was found (p > 0.05). When comparing these results with those from other investigations, it was clear that a particular rugae pattern could be established for different ethnic groups. However, the small sample size justifies further work in larger samples to validate these findings.  相似文献   
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