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971.
Carbon‐based materials are often used as matrices for matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) and its imaging (MALDI‐MSI). However, researchers have refrained from using carbon‐based fingerprint powder (CFP) as a matrix due to high background and contamination. In this work, the compatibility of CFP is reevaluated with MALDI‐MSI using a high‐resolution mass spectrometer (HRMS) and compared to traditional organic matrices. Relevant fingerprint compounds were easily distinguished from carbon cluster peaks when using HRMS. For fair comparison, half of a fingerprint was dusted with CFP while the other half was dusted with traditional organic matrices. All compounds studied had comparable, or higher, signal‐to‐noise (S/N) ratios when CFP was used as the matrix. Additionally, chemical image qualities closely followed the trend of S/N ratios. CFP proved to be an effective one‐step development and matrix application technique for MALDI‐MSI of latent fingerprints, when carbon cluster peaks are well separated by a HRMS. 相似文献
972.
Nadia Geusens B.Sc. Bart Nys Ph.D. Sébastien Charles Ph.D. 《Journal of forensic sciences》2019,64(4):1169-1172
In shooting incident investigations where it is important to estimate the shooting distance, the sodium‐rhodizonate coloring method has been used for the visualization of GSR patterns extensively. This publication describes the optimization of this method by the use of a heated press for the transfer of GSR traces on garments, as well as variation of a number of other important process parameters. Our final aim for this project was to prepare a formal validation of the coloring method as prerequisite for its inclusion into the scope of ISO17025‐certified methods in the GSR Laboratory. A number of important factors and process parameters were identified, such as buffer composition and pH, type of textile used as a substrate and resolution of the documentation of the results. Results were tested using a synthetic proficiency test. Our optimized method has been found to be a very effective technique for visualization of macroscopic GSR traces. 相似文献
973.
Monika Židková Ph.D. Rachel Horsley Ph.D. Ondřej Hloch M.D. Tomáš Hložek M.Sc. 《Journal of forensic sciences》2019,64(2):647-650
Recreational use of the potent synthetic opioid 3,4‐ dichloro‐N‐(2‐(dimethylamino)cyclohexyl)‐N‐methylbenzamide (U‐47700) is rising, accompanied by increasingly frequent cases of serious intoxication. This article reports a case of near‐fatal U‐47700 intoxication. A man was found unconscious (with drug powder residues). After 40 h in hospital (including 12 h of supported ventilation), he recovered and was discharged. Liquid chromatography/high‐resolution mass spectrometry (LC/HRMS) or gas chromatography/mass spectrometry (GC/MS) were used to detect and quantify substances in powders, serum and urine. Powders contained U‐47700 and two synthetic cannabinoids. Serum and urine were positive for U‐47700 (351.0 ng/mL), citalopram (<LOQ), tetrahydrocannabinol (THC: 3.3 ng/mL), midazolam (<LOQ) and a novel benzodiazepine, clonazolam (6.8 ng/mL) and their metabolites but negative for synthetic cannabinoids. If potent synthetic opioids become cheaper and more easily obtainable than their classical counterparts (e.g., heroin), they will inevitably replace them and users may be exposed to elevated risks of addiction and overdose. 相似文献
974.
Commingling is frequently encountered in cases examined by the Committee on Missing Persons in Cyprus, and pair‐matching is routinely used as a preliminary segregation method. Here we examine the degree of bilateral asymmetry in nutrient foramen position of the radius and ulna to determine whether nutrient foramen position may be useful in visual and/or ostetometric pair‐matching. Differences in nutrient foramen position between left‐right pairs from the same individual were compared with differences in nutrient foramen position between different individuals. Bilateral asymmetry in nutrient foramen position was found to be high, indicating that it is not a reliable trait for pair‐matching. Bilateral asymmetry and between‐person variation were found to differ between the two bones examined, suggesting that nutrient foramen position in other long bones should also be tested. 相似文献
975.
976.
Nicole Yarid M.D. Emily C. Brown M.D. Markus Boos M.D. Ph.D. Jeffrey Otjen M.D. James Metz M.D. Carole Jenny M.D. Kenneth W. Feldman M.D. 《Journal of forensic sciences》2019,64(1):284-288
Traumatic cardiac ventricular ruptures in children are rare. Only a single case of left ventricular rupture due to child abuse has been reported. We report a child who sustained a fatal left ventricular apical rupture. It appeared to have resulted from hydrostatic forces resulting from abusive blunt thoracic injury. That he was being abused was previously missed when he was presented to the emergency department with facial pyoderma. It was not noted that he also had lip and oral mucosal injury, sites not affected by staph toxins. As a result, his underlying, abusive and secondarily infected, facial flow type scald burn was not appreciated. Within a week thereafter his fatal injury occurred, accompanied by extensive and obvious associated abusive injuries. Postmortem high‐detail whole body computed tomography scanning aided the autopsy. Although rare, ventricular rupture from abusive blunt thoracic injury can occur. 相似文献
977.
Furkan Paligu M.Sc. Avinash Kumar M.Sc. Hyuk Cho Ph.D. Cihan Varol Ph.D. 《Journal of forensic sciences》2019,64(5):1370-1378
As the Internet and World Wide Web have rapidly evolved and revolutionized the applications in everyday life, it is a demanding challenge for investigators to keep up with the emerging technologies for forensic analyses. Investigating web browser usages for criminal activities, also known as web browser forensics, is a significant part of digital forensics as crucial browsing information of the suspect can be discovered. Particularly, in this study, an emerging web storage technology, called IndexedDB, is examined. Characteristics of IndexedDB technology in five major web browsers under three major operating systems are scrutinized. Also, top 15 US websites ranked by Alexa are investigated for their data storage in IndexedDB. User screen names, ids, and records of conversations, permissions, and image locations are some of the data found in IndexedDB. Furthermore, BrowStEx, a proof‐of‐concept tool previously developed, is extended and cultivated into BrowStExPlus, with which aggregating IndexedDB artifacts is demonstrated. 相似文献
978.
Heejin Kim 《Computer Law & Security Report》2019,35(5):105315
Electronic commerce has brought about business and technological changes globally, and these global changes have given rise to major legal reforms across nations. In the fast-changing global digital economy, states need strategies to maintain competitiveness of their markets while simultaneously ensuring the secure and effective use of technologies involved in conducting electronic transactions. This paper examines how the use and recognition of electronic signatures are regulated in Southeast Asia – the region that has shown the most significant growth in global e-commerce in past few years. Based on a comparative analysis of the laws of four representative ASEAN member states – namely Singapore, Thailand, Malaysia, and Vietnam, this paper argues that there is a regional trend towards adopting more liberal and technology-neutral standards for electronic signatures. Electronic signature regulation in Southeast Asia is now built upon limited technological neutrality (or the so-called “two-tiered” approach) as a shared regulatory understanding, but this approach is operationalized differently in each state due to distinctive national contexts. Within the common legal framework, each state has developed its own system of control and management with respect to higher-level signatures (using advanced technologies). The principle of technological neutrality, a concept originally developed for the regulation of technologies in response to the liberalization of telecommunications market, has been the central theme of discussions on the e-transactions policy-making scene. As the author shows, in the process through which states localize the global standards of technological neutrality, ASEAN as a vehicle of regulatory change has played an essential role in translating this principle to the national context. 相似文献
979.
Chenguo Zhang 《Computer Law & Security Report》2019,35(4):462-475
Although Uber's arrival in China has resulted in disruptive competition for incumbent taxi companies, it offers an attractive alternative in China's supply-demand-imbalanced urban passenger transport system. China's regulatory regime for Uber has evolved in three stages: from the regulatory vacuum prior to 2015 to its official legalization in 2015–2016, and the enactment of numerous local regulations in 2016, with specific and more demanding requirements for Uber. This policy is a part of the Chinese approach to the gradual liberalization of the urban passenger transport market. Policymakers should consider ‘fair competition’ as the guiding principle to balance the interests of sharing firms and incumbent service providers, as well as between different sharing firms. The core value of this principle lies in the benefits it provides for consumers and the way it engenders a pro-competitive market environment. The labor protection arrangements for sharing firms’ laborers should be more flexible and diversified. In order to recognize whether an Uber-Driver is an employee or independent contractor, a new standard taking into account a range of factors should be established through collective negotiations between the participants of the sharing economy, and dialogues between members of the judiciary, academics, and the policymakers. Further, consumer protection law and personal data protection provisions should apply when sharing firms misuse their distinctive algorithmic management model to compete unfairly to the detriment of consumers and other users. Ex ante regulatory measures designed to protect the personal data of users should be introduced for deployment in the context of the sharing economy. When enforcing these rules, a balance should be struck ensuring free data flow that is essential to sharing firms’ innovation and competition, and the need to ensure the level of data security required to underpin a well-functioning sharing society. 相似文献
980.
Quantifying the amount of cortical bone loss is one variable used in histological methods of adult age estimation. Measurements of cortical area tend to be subjective and additional information regarding bone loss is not captured considering cancellous bone is disregarded. We describe whether measuring bone area (cancellous + cortical area) rather than cortical area may improve histological age estimation for the sixth rib. Mid‐shaft rib cross‐sections (n = 114) with a skewed sex distribution were analyzed. Ages range from 16 to 87 years. Variables included: total cross‐sectional area, cortical area, bone area, relative bone area, relative cortical area, and endosteal area. Males have larger mean total cross‐sectional area, bone area, and cortical area than females. Females display a larger mean endosteal area and greater mean relative measure values. Relative bone area significantly correlates with age. The relative bone area variable will provide researchers with a less subjective and more accurate measure than cortical area. 相似文献