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951.
Ricardo Real P. Sousa 《国际相互影响》2015,41(4):621-647
The study of external interventions in conflict management is critical and has implications for international relations and conflict theory. Quantitative studies of the relationship between external interventions and civil war have been prone to some conceptual limitations (understudied lower-intensity periods) and data limitations (unavailability of event battle death data). This article presents a new external interventions data set covering the period between 1989 and 2010 for Africa, building on the Regan et al. (2009) data set, which covers the period between 1945 and 1999. Novel features of this new data set are: the recoding of the overlap period; a broader range of categories of intervention, including UN and non-UN missions; and wider temporal scope, by extending the period of analysis to 2010, by lowering the civil war threshold to 25 battle deaths, and by starting the conflict period from the date of the first battle death in each civil war (based on UCDP GED version-1.5-2011). The advantages of the data set are illustrated with an analysis of the different effects interventions have on high- and low-intensity conflict periods. 相似文献
952.
TESTING FOR TEMPORALLY DIFFERENTIATED RELATIONSHIPS AMONG POTENTIALLY CRIMINOGENIC PLACES AND CENSUS BLOCK STREET ROBBERY COUNTS 总被引:3,自引:0,他引:3 下载免费PDF全文
This study examined street robbery patterns in Philadelphia, Pennsylvania, from the years 2009 to 2011 to determine whether the effects of potentially criminogenic places are different across different periods of the day. Census block (N = 13,164) street robbery counts across four periods (6:45 a.m . to 9:59 a.m., 10:00 a.m . to 4:29 p.m ., 4:30 p.m . to 9:14 p.m ., and 9:15 p.m. to 6:44 a.m. ) were modeled with 12 different potentially criminogenic places, 3 measures of illicit markets, 4 compositional control variables, and spatially lagged versions of the 12 potentially criminogenic places and population using simultaneously estimated negative binomial regression models. Differences in the magnitudes of the parameter estimates across the time periods were assessed with Wald tests. Overall, the patterns across the four models were mostly consistent with the effects hypothesized based on the study's crime pattern theory and time‐geography theoretical frame; yet differences in the magnitudes of the coefficients were less pronounced than hypothesized. Overall, the results provide moderate support for the crime pattern theory and time‐geography explanation of spatial‐temporal robbery patterns; however, numerous points are raised for future crime and place research. 相似文献
953.
Comparison of the Columnar‐Thin‐Film and Vacuum‐Metal‐Deposition Techniques to Develop Sebaceous Fingermarks on Nonporous Substrates, 下载免费PDF全文
Stephanie F. Williams M.P.S. Drew P. Pulsifer Ph.D. Robert C. Shaler Ph.D. Robert S. Ramotowski M.S. Shelly Brazelle M.S. Akhlesh Lakhtakia Ph.D. D.Sc. 《Journal of forensic sciences》2015,60(2):295-302
Both the columnar‐thin‐film (CTF) and the vacuum‐metal‐deposition (VMD) techniques for visualizing sebaceous fingermarks require the deposition of a material thereon in a vacuum chamber. Despite that similarity, there are many differences between the two techniques. The film deposited with the CTF technique has a columnar morphology, but the film deposited with the VMD technique comprises discrete islands. A split‐print methodology on a variety of fingermarked substrates was used to determine that the CTF technique is superior for developing fingermarks on clear sandwich bags and partial bloody fingermarks on stainless steel. Both techniques are similar in their ability to develop fingermarks on glass but the CTF technique yields higher contrast. The VMD technique is superior for developing fingermarks on white grocery bags and the smooth side of Gloss Finish Scotch Multitask? tape. Neither technique worked well for fingermarks on black garbage bags. 相似文献
954.
Harris Mushtaq B.Eng. Shahryar Rahnamayan Ph.D. P.Eng. Areeb Siddiqi B.Eng. 《Journal of forensic sciences》2015,60(1):212-218
Color separation is an image processing technique that has often been used in forensic applications to differentiate among variant colors and to remove unwanted image interference. This process can reveal important information such as covered text or fingerprints in forensic investigation procedures. However, several limitations prevent users from selecting the appropriate parameters pertaining to the desired and undesired colors. This study proposes the hybridization of an interactive differential evolution (IDE) and a color separation technique that no longer requires users to guess required control parameters. The IDE algorithm optimizes these parameters in an interactive manner by utilizing human visual judgment to uncover desired objects. A comprehensive experimental verification has been conducted on various sample test images, including heavily obscured texts, texts with subtle color variations, and fingerprint smudges. The advantage of IDE is apparent as it effectively optimizes the color separation parameters at a level indiscernible to the naked eyes. 相似文献
955.
Nondestructive Methods for Recovery of Biological Material from Human Teeth for DNA Extraction 下载免费PDF全文
Montserrat Hervella Ph.D. Maitane G. Iñiguez M.Sc. Neskuts Izagirre Ph.D. Alberto Anta Ph.D. Concepción de‐la‐Rúa Ph.D. 《Journal of forensic sciences》2015,60(1):136-141
The extraction of DNA from human skeletal remains applied to forensic, and evolutionary studies do not exclude risks, which are to be evaluated when working with unique specimens that could be damaged or even destroyed. In the present study were evaluated several nondestructive methods for recovering DNA instead of the most currently used pulverization method. Three different procedures to access inside the dental pieces (occlusal perforation, cervical perforation, and cervical cut) have been compared with the aim of recovering as many cell remains as possible to carry out a DNA extraction. Given the DNA quantitation results, a method was proposed that consists of a cervical cut to facilitate the access to the pulp cavity and a subsequent filing of the root canals down to the apex of the dental root. This methodology allows the recovery of both mitochondrial and nuclear DNA, with the minimum deterioration for the dental pieces. 相似文献
956.
Comparing Electronic News Media Reports of Potential Bioterrorism-Related Incidents Involving Unknown White Powder to Reports Received by the United States Centers for Disease Control and Prevention and the Federal Bureau of Investigation: U.S.A., 2009–2011 下载免费PDF全文
Geroncio C. Fajardo M.D. M.B.A. M.S. M.S. Joseph Posid M.P.H. Stephen Papagiotas M.P.H. Luis Lowe M.S. M.P.H. 《Journal of forensic sciences》2015,60(Z1):S76-S82
There have been periodic electronic news media reports of potential bioterrorism-related incidents involving unknown substances (often referred to as “white powder”) since the 2001 intentional dissemination of Bacillus anthracis through the U.S. Postal System. This study reviewed the number of unknown “white powder” incidents reported online by the electronic news media and compared them with unknown “white powder” incidents reported to the U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Federal Bureau of Investigation (FBI) during a 2-year period from June 1, 2009 and May 31, 2011. Results identified 297 electronic news media reports, 538 CDC reports, and 384 FBI reports of unknown “white powder.” This study showed different unknown “white powder” incidents captured by each of the three sources. However, the authors could not determine the public health implications of this discordance. 相似文献
957.
Investigating the Postmortem Molecular Biology of Cartilage and its Potential Forensic Applications 下载免费PDF全文
Shawna N. Bolton M.Sc. Michael P. Whitehead Ph.D. Jayesh Dudhia Ph.D. Timothy C. Baldwin Ph.D. Raul Sutton Ph.D. 《Journal of forensic sciences》2015,60(4):1061-1067
This study investigated the postmortem molecular changes that articular cartilage undergoes following burial. Fresh pig trotters were interred in 30‐cm‐deep graves at two distinct locations exhibiting dissimilar soil environments for up to 42 days. Extracts of the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joint cartilage from trotters disinterred weekly over 6 weeks were analyzed by Western blot against the monoclonal antibody 2‐B‐6 to assess aggrecan degradation. In both soil conditions, aggrecan degradation by‐products of decreasing molecular size and complexity were observed up to 21 days postmortem. Degradation products were undetected after this time and coincided with MCP/MTP joint exposure to the soil environment. These results show that cartilage proteoglycans undergo an ordered molecular breakdown, the analysis of which may have forensic applications. This model may prove useful for use as a human model and for forensic investigations concerning crimes against animals and the mortality of endangered species. 相似文献
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