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341.
At outdoor crime scenes, cadaver-detection and blood-detection dogs may be tasked with locating blood that is days, weeks or months old. Although it is known that the odour profile of blood will change during this time, it is currently unknown how the profile changes when exposed to the environment. Such variables must be studied in order to understand when the odour profile is no longer detectable by the scent-detection dogs and other crime scene tools should be implemented. In this study, blood was deposited onto concrete and varnished wood surfaces and weathered in an outdoor environment over a three-month period. Headspace samples were collected using solid phase microextraction (SPME) and analysed using comprehensive two-dimensional gas chromatography – time-of-flight mass spectrometry (GC×GC–TOFMS). The chemical odour profiles were compared with the behavioural responses of cadaver-detection and blood-detection dogs during training. Data interpretation using principal component analysis (PCA) and hierarchical cluster analysis (HCA) established that the blood odour could no longer be detected using SPME–GC×GC–TOFMS after two months of weathering on both surfaces. Conversely, the blood-detection dogs had difficulty locating the blood samples after one month of weathering on concrete and after one week of weathering on varnished wood. The scent-detection dogs evaluated herein had not been previously exposed to environmentally weathered blood samples during training. Given that this study was conducted to test the dogs' baseline abilities, it is expected that with repeated exposure, the dogs' capabilities would likely improve. The knowledge gained from this study can assist in providing law enforcement with more accurate training aids for blood-detection dogs and can improve their efficiency when deployed to outdoor crime scenes.  相似文献   
342.
Our (2014) model for the regulation of cognitive enhancement devices (CEDs) received a great deal of interest from those involved in European device regulation and from academic commentators. Further, since the publication of our recommendations, the number of manufacturers of brain stimulation devices for non-medical purposes has increased, underscoring the need for a regulatory response. In this paper, we clarify aspects of our original proposal and address additional regulatory issues beyond our original focus on the sale of devices. We begin with theoretical points pertaining to the definition of a CED and the distinction between treatment and enhancement. We then respond to practical challenges raised by the prospect of implementing our regulatory framework. Next, we address some wider societal considerations relating to users and other stakeholders. Finally, we revisit the broader regulatory context within which the various discussions are situated.  相似文献   
343.
Among currently available technologies, transcranial direct current stimulation (tDCS) is one of the most promising neuroenhancements because it is relatively effective, safe, and affordable. Recently, lay people have begun to build—or purchase—the tDCS device to use it at home for treatment or as a cognitive enhancer. The tDCS device is currently not covered by the existing regulatory framework, but there are still significant potential risks of misusing this device, and its long-term effects on the brain have not been fully explored. Thus, researchers have argued the need for regulations or official guidelines for the personal use of tDCS. However, until now, no systematic research on the do-it-yourself (DIY) tDCS user community has been done. The present study explores the basic demographic characteristics of DIY tDCS users as well as why and how they are using this device through a questionnaire survey, in-depth interviews, and a content analysis of web postings on the use of tDCS. This preliminary but valuable picture of the DIY tDCS user community will shed light on future studies and policy analysis to craft sound regulations and official guidelines for the use of tDCS.  相似文献   
344.
Nitrites are commonly used in the chemical, pharmaceutical, and food industries. Recently, they have been identified in cases of voluntary intoxication. We report the case of a 13-year-old girl who was found lifeless on her bed next to a glass containing a white powder and a bottle containing a white powder with a moistened appearance. External examination and autopsy revealed a nonspecific asphyxia syndrome, which was confirmed by the pathological analysis. Analysis of the samples revealed metoclopramide in the peripheral blood at a concentration of 0.402 mg/L (LC–HRMS). An analysis of the gastric contents was carried out after sodium nitrite was detected in the powders found near the body (Raman spectrometry). Nitrites were found in the gastric fluid at a concentration of 30.9 mg/L. Death occurred secondary to anoxia, following ingestion of nitrites; suicide kits are available on the web and nitrites are relatively easy to source and inexpensive. Nitrites are delivered in powder form to be dissolved in liquid, which may then be consumed with metoclopramide (or an alternative anti-emetic drug) to maximize absorption and reduce emesis. The toxic effect of nitrites lies in their oxidizing power, causing the transformation of hemoglobin into methemoglobin, which, when it accumulates, induces tissue anoxia resulting in death. There has been an alarming increase in the number of cases linked to suicide using nitrites or a nitrite suicide kit. The fact that nitrites are readily available online underscores the importance of establishing effective preventive measures such as limiting the access and use of this chemical.  相似文献   
345.
建设社会主义法治国家,离不开司法独立,作为司法之关键的审判活动对中国的法治进程起着重要的作用。从审判独立的内涵出发,分析审判独立的的价值,阐述中国审判独立的发展历程及中国当前审判独立的运行情况。在此基础之上剖析影响中国审判独立的几种关系,有助于切实推进我国的司法体制改革,最终实现法治国家的目标。  相似文献   
346.
比较与借鉴:中外青年志愿服务现状透视   总被引:4,自引:1,他引:3  
国外发达国家青年志愿服务工作已逐渐步入组织化、规范化和系统化的轨道。通过中外志愿服务的比较发现,我国青年志愿服务水平与社会成员的需求仍然有较大的差距。应借鉴与吸收国外的成功经验,以更好地推动我国青年志愿服务工作的持续发展。  相似文献   
347.
Objective documentation of tears and abrasions to the external genitalia after sexual assault is an important part of the forensic examination. A 1% aqueous solution of toluidine blue (TB) dye is often used to highlight injury, but the dye can be difficult to see on dark skin. We evaluated a fluorescent dye for detecting injuries on all skin colors in a relevant preclinical murine model. We compared the ability of trained, blinded observers to detect unstained wounds and wounds stained with 1% fluorescein sodium (FL) and with TB. We also evaluated the cutaneous wound healing response after application of both dyes. The no‐dye group had significantly fewer (p < 0.05) true‐positive identifications compared to all the dye groups. No differences in effectiveness were detected between dye treatments. All groups exhibited statistically similar healing rates. These findings support the evaluation of fluorescein sodium in a future clinical study with human subjects.  相似文献   
348.
Plakophilin‐2 (PKP2) variants could produce a phenotype of Brugada syndrome (BrS), which seems to be most likely the same allelic disorder as some sudden unexplained nocturnal death syndrome (SUNDS). All coding regions of PKP2 gene in 119 SUNDS victims were genetically screened using PCR and direct Sanger sequencing methods. Three novel mutations (p.Ala159Thr, p.Val200Val, and p.Gly265Glu), one novel rare polymorphism (p.Thr723Thr), and eight reported polymorphisms were identified. A compound mutation (p.Ala159Thr and p.Gly265Glu) and a rare polymorphism (p.Thr723Thr) were found in one SUNDS case with absence of the cardiomyopathic features. The detected compound mutation identified in this first investigation of PKP2 genetic phenotype in SUNDS is regarded as the plausible genetic cause of this SUNDS case. The rare incidence of PKP2 mutation in SUNDS (1%) supports the previous viewpoint that SUNDS is most likely an allelic disorder as BrS.  相似文献   
349.
中学生的不良行为严重影响其健康成长 ,对社会构成了潜在的威胁 ,已是一个不争的事实 ,应当引起社会的高度重视。要采取切实的措施 ,预防和制止不良行为的发生 ,必须深入把握当前中学生不良行为的现状和特征。  相似文献   
350.
第三方物流企业提供的是服务,服务质量是企业竞争的关键。目前我国第三方物流企业服务质量存在一些问题,主要有:物流企业的技术装备水平落后,信息化程度较低,服务效率不高;服务功能单一,服务质量较差;缺乏高素质的物流服务人才和先进的服务理念。深入分析我国物流服务质量存在的问题,以便完善第三方物流企业服务质量,构建完整的配套物流服务体系,这对我国第三方物流企业今后的发展具有重要的现实意义。  相似文献   
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