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271.
Physical matching methods are a family of well‐known methods that are utilized in order to determine whether two pieces of a tearable/breakable material used to be one object. When performing physical match of polymers, it is sometimes difficult to reach an unambiguous conclusion. This is due to various reasons. One is when the tear/fracture resides in an inaccessible or hidden‐from‐view region of the piece. Another is when the shape of the tear/fracture at the object's tear/fracture line is insufficient for deducing a complete match. Third is deficiency of material along this line. These are examples of processes where the line is affected so drastically, so that a match renders impossible. Specifically, when addressing elastic materials, the tear/fracture line may even be squashed. This may also be a reason for difficulty in performing a physical match. In this paper, a method is proposed where a match is alternatively achieved by means of photographic comparison of marks on the surface topography of the pieces‐in‐question. Comparisons of pairs of torn pieces of silicon rubber were made. The procedure involved photography of the surface topography the pieces. Then, the photographs were horizontally mirror‐flipped. Lastly, a comparison was made between two photographs: a photograph of one piece and a mirror‐flipped photograph of the opposite piece. The results show that after comparing the pieces to one another, only one unique pair turned out to be positively matched. Using the proposed method, not only the comparison is done by a more informative method (comparing to physical match), it is also more convenient, faster, less expensive, and technically simpler.  相似文献   
272.
Electronic documents often contain personal or confidential information, which can be used as valuable evidence in criminal investigations. In the digital investigation, special techniques are required for grouping and screening electronic documents, because it is challenging to analyze relationships between numerous documents in storage devices manually. To this end, although techniques such as keyword search, similarity search, topic modeling, metadata analysis, and document clustering are continually being studied, there are still limitations for revealing the relevance of documents. Specifically, metadata used in previous research are not always values present in the documents, and clustering methods with specific keywords may be incomplete because text‐based contents (including metadata) can be easily modified or deleted by users. In this work, we propose a novel method to efficiently group Microsoft Office Word 2007+ (MS Word) files by using revision identifier (RSID). Through a thorough understanding of the RSID, examiners can predict organizations to which a specific user belongs, and further, it is likely to discover unexpected interpersonal relationships. An experiment with a public dataset (GovDocs) provides that it is possible to categorize documents more effectively by combining our proposal with previously studied methods. Furthermore, we introduce a new document tracking method to understand the editing history and movement of a file, and then demonstrate its usefulness through an experiment with documents from a real case.  相似文献   
273.
The existing divergencies in the development of forensic anthropology (FA) around the world justify an analysis of its situation in each country/region. Our objective is to report information gathered directly from professionals acting in the field of forensic anthropology in Brazil, with the aim of highlighting the challenges of the discipline and contributing to its advancement. The research consisted of personal visits in Medico‐Legal Institutes (IMLs) in nine states of the country and semi‐structured interviews with 16 professionals. Detailed analysis of the Results suggests the field of forensic anthropology, despite the engagement and dedication of its professionals, cannot yet be considered a well‐structured discipline across the country. The academic background of professionals is highly heterogenous. The applied methods vary, and common protocol is not always followed. The demand highly exceeds the available human resources. The lack of comparative material Results in high percentage of cases remaining unsolved. Important divergences exist in terms of infrastructure and professional resources between the states. The limited cooperation between different IMLs and between different sections of the same IML—together with a general disbelief in the usefulness of anthropological examination in forensic cases—hampers FA’s development. There is a great openness for scientific collaboration and an abundance of material for research. Our research demonstrated structural, political, and academic limitations that affect the FA field in Brazil. However, the expertise and dedication of professionals point to human potential as the chief strength of this discipline that supports and enables research, providing high‐quality services in a challenging context.  相似文献   
274.
File‐sharing apps with Wi‐Fi hotspot or Wi‐Fi Direct functions become more popular. They can work on multiple platforms and allow users to transfer files in a concealed manner. However, when criminals use these apps in illegal activities, it becomes an important issue for investigators to find digital evidence on multiple platforms. At present, there are few studies on this topic, and most of them are limited to the single platform problem. In this paper, we propose a forensic examination method for four popular cross‐platform file‐sharing apps with Wi‐Fi hotspot and Wi‐Fi Direct functions: Zapya, SHAREit, Xender, and Feem. We use 22 static and live forensic tools for 11 platforms to acquire, analyze, and classify the forensic artifacts. In our experiments, we find many useful forensic artifacts and classify them into six categories. The experimental results can support law enforcement investigations of digital evidence and provide information for future studies on other cross‐platform file‐sharing apps.  相似文献   
275.
The analysis of cannabis plant material submitted to seized‐drug laboratories was significantly affected by the signing of the Agricultural Improvement Act of 2018, which defined hemp and removed it from the definition of marijuana in the Controlled Substances Act. As a result, field law enforcement personnel and forensic laboratories now are in need of implementing new protocols that can distinguish between marijuana‐type and hemp‐type cannabis. Colorimetric tests provide a cost‐effective and efficient manner to presumptively identify materials prior to submission to a laboratory for analysis. This work presents the validation of the 4‐aminophenol (4‐AP) color test and demonstrates its utility for discriminating between marijuana‐type and hemp‐type cannabis (i.e., typification). Validation studies included the testing of numerous cannabinoid reference materials, household herbs, previously characterized cannabis plant samples, and real‐case samples. The 4‐AP test reliably produces a pink result when the level of Δ9‐tetrahydrocannabinol (THC) is approximately three times lower than the level of cannabidiol (CBD). A blue result is generated when the level of THC is approximately three times higher than that of CBD. Inconclusive results are observed when the levels of THC and CBD are within a factor of three from each other, demonstrating the limitations of the test under those scenarios.  相似文献   
276.
我国近年来反腐败问题研究综述   总被引:7,自引:0,他引:7  
本文从腐败本质问题界定、腐败行为特征及其成因、腐败测度、反腐败策略四个方面,对我国反腐败问题进行了文献综述。本文提出,腐败是滥用公共权力谋取特殊权利的一切行为。当前我国腐败行为呈现出绝对权力腐败猖獗、从滥用公共权力向滥用公共资源转变、腐败手段更加复杂和隐蔽、灰色腐败倾向明显等新特征。滥用权力的欲望、官员的经济理性、公共权力寻租、行政监督缺位、行政道德失范是腐败产生的主要原因。中国应创新腐败测度方法,科学测度腐败程度,推进反腐国际化。客观权衡腐败零容忍、全面反腐、权力反腐的利弊,综合使用经济处罚、道德教育与法律惩处手段,加强对腐败行为的行政监督。  相似文献   
277.
The medicolegal death investigation system in the Kingdom of Saudi Arabia (KSA) is unique in the world. It is exclusively derived from Islamic judiciary based on Shari'ah law, which is the definitive Islamic law or doctrine. This law is applied on Saudi citizens as well as foreigners. This is different from other Islamic countries, which have a combination of Islamic and other judiciary systems.The forensic medicine centers in KSA are related administratively to the Ministry of Health (MOH) and its subdivisions in the different governorates. They are concerned with forensic medical examination and autopsy, as well as the clinical forensic medical examination of sexual assault cases, and those injured in civil and criminal cases. The assisting laboratories (forensic histopathology, microbiology, serology, forensic chemistry) are working independently under the funding of MOH, whereas the DNA laboratory and other departments of forensic sciences, for example, counterfeiting and forgery unit are related administratively to the Ministry of Interior represented by the Administration of Criminal Evidences. Efforts concerning crime scene investigations are shared with Administration of Criminal Evidences' crime scene investigators.Forensic medicine education in KSA developed in the past few years after the foundation of Saudi specialty certificate in forensic medicine. The certificate is a postgraduation qualification equivalent to a doctorate degree in forensic medicine and requires completion of a 4-year training program in both MOH- and Ministry of Interior-related departments, as well as passing annual evaluation and examination.This review is aimed at providing in the next decade the medicolegal centers with national forensic specialists throughout the kingdom and granting skillful headships for the next generations. Moreover, this review suggests more scientific associations with the academic universities in the various fields of forensic sciences through academic cooperation.  相似文献   
278.
Big data shows great promise in public services to personalized e-government service delivery. Big data is a new generation of extracting value from a large volume of data sources with enabling high-velocity capture, analysis, and discovery for forecasting and better decision making. This article discusses the potential of big data application in e-government based on survey findings from smartphone habit as part of big data source. Data produced from smartphones usage is one of the main sources of big data. Online services can easily be accessed using smartphones, which support continuous engagement with citizens using e-government services. This study deployed quantitative survey findings from the smartphone habit of users in Brunei Darussalam. It presents an interpretative model that examines the important factors to consider big data in public services and discusses general challenges for integrating e-government services facing a big data era.  相似文献   
279.
Patients suffering from psychiatric disorders have an excess mortality and a shorter life span expectancy compared to the general population. Furthermore, they are treated with multiple drugs and are known to have an increased risk of drug abuse. In this study, we aimed at investigating the pharmaceutical drug and drug of abuse profiles of the deceased included in the Danish prospective autopsy‐based forensic study on psychiatric patients, SURVIVE. Using the postmortem systematic toxicological analysis results, we identified 129 different consumed compounds in our population (n = 443). Polypharmacy (≥5 compounds) was detected in 39.5% of the deceased. Deceased with a psychiatric diagnosis or who died from a fatal intoxication had significantly more compounds at the time of their death compared to having either no psychiatric diagnosis or another cause of death, respectively. Evidence of drug abuse was present, as 29.8% of our total population had consumed either methadone or illicit drugs of abuse, excluding tetrahydrocannabinol. Of those deceased with a psychiatric diagnosis, 33.6% had either consumed methadone or illicit drugs of abuse, a greater number than those without a psychiatric diagnosis. Fatal intoxication was the most frequent cause of death (40.6%) with methadone as the major intoxicant. Here, we found that those without a psychiatric diagnosis had fewer fatal pharmaceutical drug intoxications compared to the psychiatric diagnosis groups. Our findings add further context to understanding the excess mortality of psychiatric patents, since there is an increased occurrence of fatal intoxication, polypharmacy, and drug abuse in this population.  相似文献   
280.
Compound-specific isotope analysis offers potential for fingerprinting of diesel fuels, however, possible confounding effects of isotopic fractionation due to evaporation need to be assessed. This study measured the fractionation of the stable carbon and hydrogen isotopes in n-alkane compounds in neat diesel fuel during evaporation. Isotope ratios were measured using a continuous flow gas chromatograph/isotope ratio mass spectrometer. Diesel samples were progressively evaporated at 24 ± 2°C for 21 days. Increasing depletion of deuterium in nC12nC17 alkanes in the remaining liquid with increasing carbon chain length was observed. Negligible carbon isotope fractionation was observed. Preferential vaporization was measured for the shorter chain n-alkanes and the trend decreased with increasing chain length. The decrease in δ2H values indicates the preferential vaporization of the isotopically heavier species consistent with available quantitative data for hydrocarbons. These results are most important in the application of stable isotope technology to forensic analysis of diesel.  相似文献   
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