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771.
Comparison of the Columnar‐Thin‐Film and Vacuum‐Metal‐Deposition Techniques to Develop Sebaceous Fingermarks on Nonporous Substrates,
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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
772.
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
773.
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
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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
774.
Jamie K. Pringle Ph.D. John P. Cassella Ph.D. John R. Jervis Ph.D. Anna Williams Ph.D. Peter Cross M.Sc. Nigel J. Cassidy Ph.D. 《Journal of forensic sciences》2015,60(4):1052-1060
In homicide investigations, it is critically important that postmortem interval and postburial interval (PBI) of buried victims are determined accurately. However, clandestine graves can be difficult to locate; and the detection rates for a variety of search methods (ranging from simple ground probing through to remote imaging and near‐surface geophysics) can be very low. In this study, simulated graves of homicide victims were emplaced in three sites with contrasting soil types, bedrock, and depositional environments. The long‐term monthly in situ monitoring of grave soil water revealed rapid increases in conductivity up to 2 years after burial, with the longest study evidencing declining values to background levels after 4.25 years. Results were corrected for site temperatures and rainfall to produce generic models of fluid conductivity as a function of time. The research suggests soilwater conductivity can give reliable PBI estimates for clandestine burials and therefore be used as a grave detection method. 相似文献
775.
Investigating the Postmortem Molecular Biology of Cartilage and its Potential Forensic Applications
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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
776.
TrueAllele® Genotype Identification on DNA Mixtures Containing up to Five Unknown Contributors
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Mark W. Perlin Ph.D. M.D. Jennifer M. Hornyak M.S. Garett Sugimoto M.S. Kevin W.P. Miller Ph.D. 《Journal of forensic sciences》2015,60(4):857-868
Computer methods have been developed for mathematically interpreting mixed and low‐template DNA. The genotype modeling approach computationally separates out the contributors to a mixture, with uncertainty represented through probability. Comparison of inferred genotypes calculates a likelihood ratio (LR), which measures identification information. This study statistically examined the genotype modeling performance of Cybergenetics TrueAllele® computer system. High‐ and low‐template DNA mixtures of known randomized composition containing 2, 3, 4, and 5 contributors were tested. Sensitivity, specificity, and reproducibility were established through LR quantification in each of these eight groups. Covariance analysis found LR behavior to be relatively invariant to DNA amount or contributor number. Analysis of variance found that consistent solutions were produced, once a sufficient number of contributors were considered. This study demonstrates the reliability of TrueAllele interpretation on complex DNA mixtures of representative casework composition. The results can help predict an information outcome for a DNA mixture analysis. 相似文献
777.
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779.
María del P. Pablo‐Romero Antonio Sánchez‐Braza José Manuel González‐Limón 《政策研究评论》2015,32(5):576-599
The Covenant of Mayors (CM) is the mainstream European movement involving local authorities who voluntarily commit to increase energy efficiency and the use of renewable energy sources within their territories with the aim of reducing CO2 emissions and meet the European Union objectives by 2020. One country that has a greater number of signatories of this agreement is Spain. This article analyzes which factors influence the decision of Spanish local authorities to join the ever‐growing movement. An empirical model is formulated to describe the behavior of Spanish local governments, this being a binary choice model which is a function of various political, economic, and technical factors. Among the prominent factors that influence this decision are population, availability of renewable energy, fiscal and environmental stress, citizens’ political preference, the contagion effect of neighboring municipalities, the existence of covenant coordinators, and finally, economic motivations. 相似文献
780.