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Rural internet use, although still limited, is growing, raising the question of how rural people are using social media politically. As a vehicle of communication that permits the rapid transmission of information, images and text across space and connections between dispersed networks of individuals, does technological advance in rural areas presage significant political transformations? This article investigates this question in the light of a poor result for the Cambodian People’s Party in the 2013 elections, and the subsequent banning of the main opposition party, before the 2018 elections. Expanding internet use in rural areas has linked relatively quiescent rural Cambodians for the first time to networks of information about militant urban movements of the poor. Rural Cambodians are responding to this opportunity through strategies of quiet encroachment in cyberspace. This has had real effects on the nature of the relationship between the dominant party and the rural population and suggests the declining utility of the election-winning strategy used by the party since 1993. However, the extent of this virtual information revolution is limited, since neither the urban nor rural poor are mapping out new online political strategies, agendas or identities that can push Cambodia’s sclerotic politics in new directions. 相似文献
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Preparation of a Ytterbium‐tagged Gunshot Residue Standard for Quality Control in the Forensic Analysis of GSR 下载免费PDF全文
Nigel G.R. Hearns Ph.D. Denis N. Laflèche Chem.Eng.Tech.Dipl. Mark L. Sandercock Ph.D. 《Journal of forensic sciences》2015,60(3):737-742
Preparation of a ytterbium‐tagged gunshot residue (GSR) reference standard for scanning electron microscopy and energy dispersive X‐ray spectroscopic (SEM‐EDS) microanalysis is reported. Two different chemical markers, ytterbium and neodymium, were evaluated by spiking the primers of 38 Special ammunition cartridges (no propellant, no projectile) and discharging them onto 12.7 mm diameter aluminum SEM pin stubs. Following SEM‐EDS microanalysis, the majority of tri‐component particles containing lead, barium, and antimony (PbBaSb) were successfully tagged with the chemical marker. Results demonstrate a primer spiked with 0.75% weight percent of ytterbium nitrate affords PbBaSb particles characteristic of GSR with a ytterbium inclusion efficiency of between 77% and 100%. Reproducibility of the method was verified, and durability of the ytterbium‐tagged tri‐component particles under repeated SEM‐EDS analysis was also tested. The ytterbium‐tagged PbBaSb particles impart synthetic traceability to a GSR reference standard and are suitable for analysis alongside case work samples, as a positive control for quality assurance purposes. 相似文献
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T T Noguchi J J Eng E C Klatt 《The American journal of forensic medicine and pathology》1988,9(4):304-309
This article presents the significance of cyanide in medicolegal investigation of fires. It discusses the various aspects of fire investigation and the pathophysiology of cyanide toxicity and evidence interpretation in fire investigations. 相似文献
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Yan Yang B.Eng. Avi Koffman B.Sc. Gil Hocherman M.Sc. Lawrence M. Wein Ph.D. 《Journal of forensic sciences》2014,59(1):103-111
Firearms identification imaging systems help solve crimes by comparing newly acquired images of cartridge casings or bullets to a database of images obtained from past crime scenes. We formulate an optimization problem that bases its matching decisions not only on the similarity between pairs of images, but also on the time and spatial location of each new acquisition and each database entry. The objective is to maximize the detection probability subject to a constraint on the false positive rate. We use data on all cartridge casings matches detected in Israel during 2006–2008 to estimate most of the model parameters. We estimate matching accuracy from two different studies and predict that the optimal use of extraneous information would increase the detection probability from 0.931 to 0.987 and from 0.707 to 0.844, respectively. These improvements are achieved by favoring pairs of images that are closer together in space and time. 相似文献
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John W. Bond O.B.E. D.Phil Sarah V. Hainsworth Ph.D. Tien L. Lau B.Eng. 《Journal of forensic sciences》2013,58(4):1003-1007
In the United Kingdom, theft of lead is common, particularly from churches and other public buildings with lead roofs. To assess the potential to distinguish lead from different sources, 41 samples of lead from 24 church roofs in Northamptonshire, U.K, have been analyzed for relative abundance of trace elements and isotopes of lead using X‐ray fluorescence (XRF) and inductively coupled plasma mass spectrometry, respectively. XRF revealed the overall presence of 12 trace elements with the four most abundant, calcium, phosphorus, silicon, and sulfur, showing a large weight percentage standard error of the mean of all samples suggesting variation in the weight percentage of these elements between different church roofs. Multiple samples from the same roofs, but different lead sheets, showed much lower weight percentage standard errors of the mean suggesting similar trace element concentrations. Lead isotope ratios were similar for all samples. Factors likely to affect the occurrence of these trace elements are discussed. 相似文献
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Teodora Zecheru Ph.D. Alexandru Dena Eng. Marius Cîrmaci Ph.D. Ciprian Său Ph.D. Cătălin Zaharia Ph.D. Claudiu Lăzăroaie Ph.D. 《Journal of forensic sciences》2018,63(3):758-765
Ballistic gelatin as simulant of the human body and organs is a support in forensics. After having obtained very good results for a new gelatin‐based composite in terms of physicochemical and rheological properties, this study focused on this material's mechanical behavior during stabbing and shooting versus bovine and porcine organs and standard ballistic gelatin. The hybrid gelatin has a predominantly elastic behavior at 23°C, whereas the elastic modulus becomes practically constant in the 10–0.1 Hz frequency range. In terms of stabbing behavior, the small variations obtained between porcine organs and surrogate are below 5%, the perforation indicating a good similarity. From the ballistic test results using 10 × 28T rubber balls, it has been seen that the hybrid ballistic gelatin conducts to more reliable and reproducible values of perforation/penetration versus standard gelatin, making from it a real candidate for use in forensic tests. 相似文献
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A Systematic Study to Understand the Effects of Particle Size Distribution of Magnetic Fingerprint Powders on Surfaces with Various Porosities 下载免费PDF全文
Serkan Gürbüz M.Sc Bahar Özmen Monkul Ph.D. Tuğba İpeksaç M.Eng. Merve Gürtekin Seden Ph.D. Melek Erol Ph.D. 《Journal of forensic sciences》2015,60(3):727-736
This study intends to design magnetite (Fe3O4)‐based magnetic fingerprint powders with different particle size distributions. It also investigates the influence of particle size distribution on the visualization of latent fingermarks with as little background staining as possible on the surfaces with various porosities in a systematic way. Two strategies were used to prepare the magnetic fingerprint formulations for this study: milling of coarse magnetite particles for different durations, and mixing of sieved fine particles with different size ranges with coarse particles. Particle size analyses of the prepared magnetic powders, optical microscopy‐based roughness analysis of the surfaces and SEM measurements of the visualized fingerprints and representative powders were performed. Mag2 of the formulations prepared through milling and Mag5 and Mag6 of the formulations prepared through sieving and mixing were more successful in the development of latent prints than the rest of the solutions. 相似文献
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The new European Union Regulation for the Registration, Evaluation, Authorisation and Restriction of Chemicals which came into force in June 2007 requires companies to work together on information relating to substances in their products in order to share data and the cost of generating new data, in order to minimise animal testing and reduce the financial burden associated with testing costs. Registrants of the same substance will be allocated to Substance Information Exchange Fora and may even form their own consortia, all with their own potential Competition Law aspects. 相似文献