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901.
Stefan Uitdehaag M.S. Wim Wiarda B.A.S. Timme Donders Ph.D. Irene Kuiper Ph.D. 《Journal of forensic sciences》2017,62(4):861-868
Soil can play an important role in forensic cases in linking suspects or objects to a crime scene by comparing samples from the crime scene with samples derived from items. This study uses an adapted ED‐XRF analysis (sieving instead of grinding to prevent destruction of microfossils) to produce elemental composition data of 20 elements. Different data processing techniques and statistical distances were evaluated using data from 50 samples and the log‐LR cost (Cllr). The best performing combination, Canberra distance, relative data, and square root values, is used to construct a discriminative model. Examples of the spatial resolution of the method in crime scenes are shown for three locations, and sampling strategy is discussed. Twelve test cases were analyzed, and results showed that the method is applicable. The study shows how the combination of an analysis technique, a database, and a discriminative model can be used to compare multiple soil samples quickly. 相似文献
902.
Yee‐Yang Teing B.Sc. Ali Dehghantanha Ph.D. Kim‐Kwang Raymond Choo Ph.D. Tooska Dargahi Ph.D. Mauro Conti Ph.D. 《Journal of forensic sciences》2017,62(3):641-654
Researchers envisioned Storage as a Service (StaaS) as an effective solution to the distributed management of digital data. Cooperative storage cloud forensic is relatively new and is an under‐explored area of research. Using Symform as a case study, we seek to determine the data remnants from the use of cooperative cloud storage services. In particular, we consider both mobile devices and personal computers running various popular operating systems, namely Windows 8.1, Mac OS X Mavericks 10.9.5, Ubuntu 14.04.1 LTS, iOS 7.1.2, and Android KitKat 4.4.4. Potential artefacts recovered during the research include data relating to the installation and uninstallation of the cloud applications, log‐in to and log‐out from Symform account using the client application, file synchronization as well as their time stamp information. This research contributes to an in‐depth understanding of the types of terrestrial artifacts that are likely to remain after the use of cooperative storage cloud on client devices. 相似文献
903.
Development of Rapid and Economical Colorimetric Screening Method for p‐Phenylenediamine in Variety of Biological Matrices and its Application to Eleven Fatal Cases of p‐Phenylenediamine Poisoning 下载免费PDF全文
Muhammad Imran M.Phil. Hafiz Faisal Usman M.S. Humera Shafi M.Phil. Muhammad Sarwar Ph.D. Muhammad Ashraf Tahir Ph.D. 《Journal of forensic sciences》2017,62(2):483-487
A rapid colorimetric method for detection of p‐phenylenediamine (PPD) in various biological samples is developed. The o‐cresol test for acetaminophen detection has been modified to detect PPD in blood, urine, gastric contents, and liver. After precipitating protein with trichloroacetic acid solution (2 mL, 10% w/v), biological specimens were required to convert PPD metabolites to PPD by acid hydrolysis. Finally, o‐cresol solution (1 mL, 1% w/v), hydrogen peroxide (200 μL, 3%v/v), and concentrated ammonium hydroxide (0.5 mL) were added in the biological samples. The presence of PPD was indicated by formation of violet color which was turned to bluish green color within 10–15 min. The limit of detection was found to be 2 mg/L in blood, urine, and gastric contents and 2 mg/Kg in liver. This method is also free from any potential interference by p‐aminophenol, acetaminophen, and other amine drugs under test conditions. This method was successfully employed to thirteen fatal cases of PPD poisoning. 相似文献
904.
The Differentiation of Menstrual from Venous Blood and Other Body Fluids on Various Substrates Using ATR FT‐IR Spectroscopy 下载免费PDF全文
Crime scene investigators and laboratory analysts use chemical tests to detect and differentiate body fluids. Testing often requires a sample of the stain, and the chemicals may cause degradation of the fluid or interfere with subsequent tests. Colorimetric chemical tests do not differentiate between different types of the same fluid, such as venous and menstrual blood, and there is no presumptive test available to simultaneously differentiate several body fluids. In this study, we recorded ATR FT ‐IR spectra of venous and menstrual blood, semen, saliva, and breastmilk. Neat and simulated casework body fluid samples were analyzed on cotton, nylon, wood, paper, and glass substrates. Differences in fluid composition, including proteins and small molecules, resulted in spectral differences. Venous and menstrual blood is differentiated by the peak at 1039 cm?1 attributed to phosphoric acid found in menstrual blood. Peak intensity is influenced by the porosity and weave of the substrate fabric. 相似文献
905.
Recovery of Trace DNA on Clothing: A Comparison of Mini‐tape Lifting and Three Other Forensic Evidence Collection Techniques 下载免费PDF全文
Trace DNA is often found in forensic science investigations. Experience has shown that it is difficult to retrieve a DNA profile when trace DNA is collected from clothing. The aim of this study was to compare four different DNA collection techniques on six different types of clothing in order to determine the best trace DNA recovery method. The classical stain recovery technique using a wet cotton swab was tested against dry swabbing, scraping and a new method, referred to as the mini‐tape lifting technique. Physical contact was simulated with three different “perpetrators” on 18 machine‐washed garments. DNA was collected with the four different DNA recovery methods and subjected to standard PCR‐based DNA profiling. The comparison of STR results showed best results for the mini‐tape lifting and scraping methods independent of the type of clothing. The new mini‐tape lifting technique proved to be an easy and reliable DNA collection method for textiles. 相似文献
906.
A Rare Case of Poisoning with a Volatile Substance: Quantitative Determination of n‐Butane in Postmortem Tissue 下载免费PDF全文
Jean Hiquet M.D. Emilie Christin M.D. Florence Tovagliaro M.D. Jean‐Michel Gaulier Pharm.D. Ph.D. Veronique Dumestre‐Toulet Pharm.D. Ph.D. Sophie Gromb‐Monnoyeur M.D. J.D. Ph.D. 《Journal of forensic sciences》2017,62(2):549-552
Poisoning with volatile substances remains exceptional. Authors report the case of a married couple who were found in a car with a butane gas bottle: the woman was dead and her husband alleged it was an unsuccessful suicide pact. A specific research of volatile substances on postmortem samples with headspace gas chromatography–mass spectrometry following a quantitative determination was performed. The n‐butane concentrations detected were composed of 610 μg/L (cardiac blood), 50 μg/kg (brain), 134 μg/kg (lungs), 285 μg/kg (liver), and 4090 μg/kg (heart) and were compatible with the rare lethal concentrations evoked in the literature. The cause of death was determined to be asphyxiation through n‐butane criminal poisoning. Authors recommendation therefore is to take samples immediately and place them in properly sealed containers and hence analyzing the samples as soon as possible after collecting them or storing them under ?30°C (?22°F) if analyses cannot be performed immediately. 相似文献
907.
Lip print analysis, or cheiloscopy, has the potential to join fingerprints and retinal scans as an additional method to determine human identification. This preliminary study sought to determine agreement among 20 raters, forensic odontologists, using an often referenced system that categorizes lip prints into six classes related to the dominant pattern of vertical, horizontal, and intersecting lines. Lip prints were taken from 13 individuals, and raters categorized eight distinct regions of each print. In addition to ratings made while viewing the actual prints, the raters repeated the exercise using photographs of the lip prints. Multirater kappa, a chance‐corrected measure of agreement, ranged between 0.15 for the actual prints and 0.25 for the photos, indicating only poor to fair levels of inter‐rater reliability. While these results fail to support the use of lip prints for human identification, it is possible that more intensive training may yet produce adequate levels of reliability. 相似文献
908.
Profile of Hospital Admissions due to Self‐Inflicted Harm in Los Angeles County from 2001 to 2010 下载免费PDF全文
Shahrzad Bazargan‐Hejazi Ph.D. Alireza Ahmadi M.D. Ph.D. Mohsen Bazargan Ph.D. Elham Rahmani M.D. Deyu Pan M.S. Golara Zahmatkesh M.D. Stacey Teruya Ed.D. M.S. 《Journal of forensic sciences》2017,62(5):1244-1250
We aimed to describe the demographic profile of self‐inflicted harm (SIH) in Los Angeles County between 2001 and 2010 and to investigate trends over this 10‐year period. We used the California Hospital Discharge Data to investigate all cases of hospital admission due to SIH, including suicide attempts and if they had a concurrent psychiatric diagnosis based on ICD‐9 codes. African‐Americans (AA) had the highest 10‐year SIH admission rates. SIH admission rates remained steady throughout the 10‐year study period. Median age of SIH was significantly lower in Latinos. Episodic mood disorders were the most common psychiatric comorbidity. The use of solid/liquid poisoning was the most common SIH method among all racial/ethnic groups. We found major disparities in SIH admissions across racial/ethnic subgroups. The importance of programs to identify, prevent, and treat SIH in these groups is discussed. 相似文献
909.
Together with the increase in the number of public‐private contracts, recent years have seen a marked proliferation in public‐private arbitrations. This article explores the public interest implications which may arise in such arbitrations and examines how public‐private arbitration is treated under English law. We argue that, due to the lack of a developed administrative law sphere in England and the historical development of arbitration as an exclusively private mode of dispute resolution, the current legal framework of arbitration in England has developed around the private law paradigm of a commercial dispute involving private actors. This private law paradigm results in a conceptual and legal void in respect of how public interest is accounted for, and protected, in arbitrations involving public bodies under English law. Therefore, we suggest that English arbitration law needs to be amended to adequately protect the private interest in public‐private arbitration. 相似文献
910.
Estimating the Skull‐to‐Camera Distance from Facial Photographs for Craniofacial Superimposition 下载免费PDF全文
Carl N. Stephan Ph.D. 《Journal of forensic sciences》2017,62(4):850-860
The overlay of a skull and a face image for identification purposes requires similar subject‐to‐camera distances (SCD) to be used at both photographic sessions so that differences in perspective do not compromise the anatomical comparisons. As the facial photograph is the reference standard, it is crucial to determine its SCD first and apply this value to photography of the skull. So far, such a method for estimating the SCD has been elusive (some say impossible), compromising the technical validity of the superimposition procedure. This paper tests the feasibility of using the palpebral fissure length and a well‐established photographic algorithm to accurately estimate the SCD from the facial photograph. Recordings at known SCD across a 1–10 m range (repeated under two test conditions) demonstrate that the newly formulated method works: a mean SCD estimation error of 7% that translates into <1% perspective distortion error between estimated and actual conditions. 相似文献