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181.
Abstract: Adipocere is a postmortem decomposition product consisting of mostly a mixture of free fatty acids (FFAs) that are formed because of the hydrolysis of triglycerides in adipose tissues. This article describes a simple and robust method for the extraction, identification, and quantification of FFA commonly found in adipocere using gas chromatography–mass spectrometry (GC/MS). This method was applied to analyze tissues from Kwäday Dän Ts’ìnchí, ancient remains discovered in a retreating glacier in the Tatshenshini‐Alsek Park, British Columbia, Canada in August 1999. The lyophilized tissues were grinded and extracted with hexane. The trimethylsilyl fatty acid derivatives were analyzed by GC/MS, and the relative abundances of myristic acid, palmitic acid, oleic acid, and stearic acid were determined. Milligram per gram levels of saturated fatty acids were found in the tissues of the ancient remains, while the levels of unsaturated fatty acids, such as palmitoleic acid, were found to be negligible. The results provided further evidence of the existence of adipocere found during forensic examination of the Kwäday Dän Ts’ìnchí ancient remains.  相似文献   
182.
Abstract: An LC–MS method was developed for benzylpiperazine (BZP) and trifluoromethylphenylpiperazine (TFMPP), constituents of “party pills” or “legal herbal highs,” and their metabolites in human blood plasma. Compounds were resolved using a mixture of ammonium formate (pH 4.5, 0.01 M) and acetonitrile (flow rate of 1.0 mL/min) with a C18 column. Calibration curves were linear from 1 to 50 ng/mL (R2 > 0.99); the lower limit of quantification (LLOQ) was 5 ng/mL; the accuracy was >90%; the intra‐ and interday relative standard deviations (R.S.D) were <5% and <10%, respectively. Human plasma concentrations of TFMPP were measured in blood samples taken from healthy adults (n = 6) over 24 h following a 60‐mg oral dose of TFMPP: these peaked at 24.10 ng/mL (±1.8 ng/mL) (Cmax) after 90 min (Tmax). Plasma concentrations of 1‐(3‐trifluoromethyl‐4‐hydroxyphenyl) piperazine peaked at 20.2 ng/mL (±4.6 ng/mL) after 90 min. TFMPP had two disposition phases (t½ = 2.04 h (±0.19 h) and 5.95 h (±1.63 h). Apparent clearance (Cl/F) was 384 L/h (±45 L/h).  相似文献   
183.
National security planners have begun to look beyond reactive, tactical cyber defense to proactive, strategic cyber defense, which may include international military deterrence. The incredible power of nuclear weapons gave birth to deterrence, a military strategy in which the purpose of armies shifted from winning wars to preventing them. Although cyber attacks per se do not compare to a nuclear explosion, they do pose a serious and increasing threat to international security. Real-world examples suggest that cyber warfare will play a lead role in future international conflicts. This article examines the two deterrence strategies available to nation-states (denial and punishment) and their three basic requirements (capability, communication, and credibility) in the light of cyber warfare. It also explores whether the two most challenging aspects of cyber attacks – attribution and asymmetry – will make cyber attack deterrence an impossible task.  相似文献   
184.
新媒体作为一种全新的社会力量,已逐步普及并渗透到社会生活的各个方面,深刻地改变着社会面貌,影响着人们的思维观念和价值取向。青少年是新媒体技术使用最为广泛、最为活跃的群体,探析新媒体对青少年的影响,应该同时考虑如何控制新媒体对青少年的负面影响。  相似文献   
185.
网络社会不仅在一定程度上扩展了民众在常态政治及社会生活中的参与权、知情权、监督权、表达权,而且也通过无所不在、无所不能而又独立的方式,来获得"向正确的方向发展"的正义感与道德感。网络正成为人们日常生活的一部分,民众的心声、诉求、意愿、不满、愤怒,包括满怀激情的谴责都在网络中得到体现。本文通过对敌意的分析和解读,试图分析网络中的敌意宣泄,以及网络宣泄的优点及可能存在的问题和隐患。  相似文献   
186.
论文首先从城市轨道交通建设改善城市旅游边缘区可达性、城市轨道交通建设促进对城市旅游边缘区的旅游需求、城市轨道交通建设促进对城市旅游边缘区的旅游需求、城市轨道交通建设促进新城区的建设等4方面分析了城市轨道交通建设对城市旅游增长极形成与发展的影响机制,然后以杭州市为例,从杭州城市旅游边缘区人口的增长、杭州城市轨道建设与旅游边缘区旅游需要统筹发展、杭州城市轨道交通建设尽可能向城市旅游边缘区腹地拓展等3方面论述了杭州城市轨道交通建设对杭州城市旅游边缘区旅游增长极形成与发展的影响。  相似文献   
187.
The characteristic that discriminates gasoline from other ignitable liquids is that it contains high‐octane blending components. This study elaborates on the idea that the presence of gasoline in fire debris samples should be based on the detection of known high‐octane blending components. The potential of the high‐octane blending component alkylate as a characteristic feature for gasoline detection and identification in fire debris samples is explored. We have devised characteristic features for the detection of alkylate and verified the presence of alkylate in a large collection of gasoline samples from petrol stations in the Netherlands. Alkylate was detected in the vast majority of the samples. It is demonstrated that alkylate can be detected in fire debris samples that contain traces of gasoline by means of routine GC‐MS methods. Detection of alkylate, alongside other gasoline blend components, results in a more solid foundation for gasoline detection and identification in fire debris samples.  相似文献   
188.
The ability to determine the age of fingerprints would be immeasurably beneficial in criminal investigations. We explore the possibility of determining the age of fingerprints by analyzing various compounds as they diffuse from the ridges to the valleys of fingerprints using matrix‐assisted laser desorption/ionization mass spectrometry imaging. The diffusion of two classes of endogenous fingerprint compounds, fatty acids and triacylglycerols (TGs), was studied in fresh and aged fingerprints on four surfaces. We expected higher molecular weight TGs would diffuse slower than fatty acids and allow us to determine the age of older fingerprints. However, we found interactions between endogenous compounds and the surface have a much stronger impact on diffusion than molecular weight. For example, diffusion of TGs is faster on hydrophilic plain glass or partially hydrophilic stainless steel surfaces, than on a hydrophobic Rain‐x treated surface. This result further complicates utilizing a diffusion model to age fingerprints.  相似文献   
189.
This article provides an in‐depth assessment of lone actor terrorists’ attack planning and preparation. A codebook of 198 variables related to different aspects of pre‐attack behavior is applied to a sample of 55 lone actor terrorists. Data were drawn from open‐source materials and complemented where possible with primary sources. Most lone actors are not highly lethal or surreptitious attackers. They are generally poor at maintaining operational security, leak their motivations and capabilities in numerous ways, and generally do so months and even years before an attack. Moreover, the “loneness” thought to define this type of terrorism is generally absent; most lone actors uphold social ties that are crucial to their adoption and maintenance of the motivation and capability to commit terrorist violence. The results offer concrete input for those working to detect and prevent this form of terrorism and argue for a re‐evaluation of the “lone actor” concept.  相似文献   
190.
新形势下,基层党组织要发挥自己在教育群众、联系群众和服务群众的桥梁和纽带作用,需要做到:一是以提升自己“服务”能力为立足点,提高基层党组织资源整合能力;二是建立健全密切党群关系的机制,保证党的群众工作的常态化;三是创新群众工作的方式方法,提高党的群众工作的适应力;四是推进基层民主建设,建立健全权力运行的群众监督机制。  相似文献   
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