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121.
Ketamine deemed as a psychoactive substance has gained popularity for recreational use owing to its hallucinogenic and dissociative effects. Understanding the synthetic processes of ketamine can provide essential clues for law enforcement officers against illicit ketamine manufacturing. In this case report, a chemical company was being monitored by law enforcement officers due to its importation of precursors and materials that could be used for the synthesis of illicit drugs. After materials and products seized from this chemical company were employed for analyses using gas chromatography–mass spectrometry, liquid chromatography–high-resolution mass spectrometry, and nuclear magnetic resonance analyses, ketamine, hydroxylamine, 2-chlorophenyl cyclopentyl ketone, and cyclopentanone p-toluenesulfonylhydrazone were identified. In addition, a novel process for the synthesis of ketamine precursor 2-chlorophenyl cyclopentyl ketone from cyclopentanone p-toluenesulfonylhydrazone and 2-chlorobenzaldehyde was validated. This is the first report to uncover this novel process for the synthesis of 2-chlorophenyl cyclopentyl ketone and can be used to increase awareness among law enforcement officers and forensic practitioners about these novel starting materials for the synthesis of ketamine.  相似文献   
122.
Digitalization has increased the number of video surveillance systems that sometimes capture crime images. Traditional methods of human height estimation use projective geometry. However, sometimes they cannot be used because the video camera surveillance system is not available or has been moved and there are no reference lines on the frame. Scientific studies have developed a new method for human height estimation using 3D laser scanning. This model necessarily requires a series of approximations, which increase the final measurement error. To overcome this problem, in the present study, images of a subject are projected directly on the 3D model, estimating the height of the subject. This article describes the methodological approach adopted through the analysis of a real case study in a controlled environment executed by Carabinieri Forensic Investigation Department (Italy). The aim is to obtain a human anthropometric measure derived from frames extracted from the videos associated with the digital survey of the framed area obtained with 3D laser scanning and point cloud analysis. The result is the height estimation of five subjects filmed by a camera obtained through the combination of 2D images extracted by a DVR/surveillance systems with 3D laser scanning. Results show that most estimated measurements are less than the real measurement of the subject; it also depends on the posture of the subject while walking. Furthermore, results shows the differences between the real height and the estimated height with a statistical approach.  相似文献   
123.
Nerium oleander is an ornamental evergreen shrub belonging to the family Apocynaceae. The Apocynaceae family includes the attractive evergreen shrub known as oleander. The cardiotoxic glycoside, oleandrin, is present in all portions of the common oleander plant. Oleander consumption can result in deadly situations accidentally or as a suicide attempt. After consuming kettle-boiled oleander leaf extract as part of a suicide attempt, an 80-year-old man was discovered comatose in his home and taken to our emergency room. The patient's heart rate was 30 beats per minute, and he had hypotension. Arterial blood gas analysis revealed remarkable metabolic acidosis and hyperkalemia (K: 7.7 mEq/L). An electrocardiogram showed a wide QRS wave, similar to a sine curve. The patient collapsed following cardiac arrest soon after hospital arrival. Veno-arterial extracorporeal membrane oxygenation was initiated; however, the patient eventually died. The serum level of oleandrin at hospital arrival, subsequently measured by LC–MS/MS, was found to be 33.4 ng/mL, far above the levels reported in previous fatal cases.  相似文献   
124.
Abstract

The discipline of public administration in the Philippines has been undergoing its version of an ‘identity crisis’ over the past decade. This crisis has been manifested in four areas: (1) the inordinate influence of mostly American public administration theories and concepts upon Philippines public administration has led Filipino academics in the early to mid-1980s to ask the question ‘is there a Philippine public administration?’; (2) the perceived disconnect between theories of public administration as taught in schools and the realities in the outside world has raised questions of the relevance of the discipline to real world challenges; (3) the continued frustration over the perception that in spite of many public administration and governance reforms, the Philippines continues to be among the more corrupt nations in the region; and (4) the recent fascination of academics in other disciplines, especially economists, that ‘institutions matter’, has led some public administration scholars to argue that their discipline has been arguing precisely the same point since the 1950s.  相似文献   
125.
Oversight function is a major component of the activities of modern legislatures irrespective of the form of government in practice. This study examines the extent to which the Nigerian legislature, characterised by infrequent appearances on the political scene and operating in an environment largely dominated by the executive arm, has performed its oversight role. The study, which is basically empirical, argues that the Nigerian legislature has been incapable of effectively performing its oversight role because, in addition to constraints like executive interference, crippling internal conflict, inexperience and high rate of members turnover hampering legislative efficiency, the legislature has compromised its role. However, occasional flashes of a measure of assertiveness by the legislature suggest that with effective mitigation of its internal problems its performance will improve as legislative culture deepens.  相似文献   
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127.
当前学者们对中国核战略的争论焦点在于,没有任何一种现有核战略定义能够完全涵盖中国核政策的特点。本文认为,正确理解中国核战略,需要摆脱现有核战略理论概念体系的束缚。只有从中国核战略产生和发展的具体时代背景中寻找线索,才能认识到,中国核战略经历了从反核威慑战略到最低核威慑战略的巨大转变,而中国长期大规模备战核战争遗留下来的物质遗产和思想基础,仍然对中国核战略产生着巨大的影响力。中国学者应从中国核战略实践出发,参与构建主流话语体系,为核战略学科建设做出自己的贡献。  相似文献   
128.
任何全球减排路线图的绘制都无法脱离国际正义而具有生命力。气候变化问题的特性要求全球减排路线图尊重具有两面性的国际气候正义:环境正义和发展正义,需要考虑国家间公平、人的公平和代际公平。仅以人类发展指数(HDI)作为衡量国家承担减排责任的标准缺乏足够的正义,至少还需要加入人均历史累积排放和气候变化脆弱性两个指标。三者分别体现气候变化正义性中的人的平等发展权、减排责任分担和对受害者在排放权上的补偿。综合三大指标后的四分组分类,才是更体现正义性、更容易被接受和执行的路线图。从正义性出发,中国应承担相应的减排责任,并努力推动全球减排进程,但也要注意维护自身的发展权益。中国在全球减排中的作为,应是在国际正义与国家发展战略间取得平衡。  相似文献   
129.
The automated search software integrated with a scanning electron microscope (SEM/EDS) has been the standard tool for detecting inorganic gunshot residues (iGSR) for several decades. The detection of these particles depends on various factors such as collection, preservation, contamination with organic matter, and the method for sample analysis. This article focuses on the influence of equipment resolution setup on the backscattered electron images of the sample. The pixel size of these images plays a crucial role in determining the detectability of iGSR particles, especially those with sizes close to the pixel size. In this study, we calculated the probability of missing all characteristic iGSR particles in a sample using an SEM/EDS automated search and how it depends on the image pixel resolution setup. We developed and validated an iGSR particle detection model that links particle size with equipment registers and applied it to 320 samples analyzed by a forensic science laboratory. Our results show that the probability of missing all characteristic iGSR particles due to their size is below 5% for pixel sizes below 0.32 μm2. These findings indicate that pixel sizes as large as twice the one commonly used in laboratory casework, that is, 0.16 μm2, are effective for initial sample scanning, yielding good detection rates of characteristic particles that could exponentially reduce laboratory workload.  相似文献   
130.
Conventional dental age estimation relies on destructive methods such as sectioning and staining, which are unpreferable when the tooth is required for evidential or archeological preservation. MicroCT is a non-destructive, high-resolution imaging technique that allows for accurate morphometrical measurement. Although microCT technology has been applied in a variety of dental studies, studies focusing on dental age-related change and dental age estimation based on microCT imaging remain lacking. Based on the question: “How has microCT technology been applied in studying human age-related tooth morphological change and dental age estimation studies?”, the authors conducted a scoping review in accordance with the Arksey and O'Malley (2005) and the PRISMA-ScR guidelines. A literature search using five major scientific databases identified 452 articles, with 11 full-text articles being eligible to be included in the scoping review. Furthermore, 6 out of the 11 studies performed dental age estimation modeling. An overview of the parameters used in the selected articles revealed a variety of tooth characteristics, such as pulp cavity to whole tooth volume ratio, secondary dentin, as well as the diameter of root canal orifice. The findings of this scoping review highlight the extent microCT is used in studying dental age-related changes, as well as the effectiveness of microCT in dental age estimation studies. This review serves as a guide for future forensic odontology age estimation studies.  相似文献   
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