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971.
Celestina Rossi A.B.A. Lynne D. Herold Ph.D. Tom Bevel M.A. Leslie McCauley B.S. Stephanie Guadarrama M.S.F.S. 《Journal of forensic sciences》2018,63(5):1526-1532
A backspatter pattern results from blood drops that travel retrograde to an applied external force. Historically, an array of animals and nonhuman objects have been used to create and study backspatter patterns. In this study, backspatter patterns captured on foam core targets that were placed 45.72 cm (18 in) behind the impact site (occipital area of the skull) were produced by cranial gunshots to human cadavers that were reinfused with fresh defibrinated bovine blood. These patterns were compared to the backspatter patterns produced by shooting blood‐soaked sponges, a typical simulant used in controlled studies of backspatter pattern production and characteristics. The backspatter pattern produced by shooting an actual human head was found to be different than those of blood‐soaked sponges in the number of stains produced, the size and size range of the stains, and the stain dispersion patterns. 相似文献
972.
973.
It is important to understand the extent of transfer of explosive particles to different surfaces in order to better evaluate potential cross-contamination by explosives in crowded security controls such as those at airports. This work investigated the transfer of nine explosive residues (ANFO, dynamite, black powder, TNT, HMTD, PETN, NH4NO3, KNO3, NaClO3) through fingerprints from one surface to another. First, the extent of adhesion of explosive residues from different surfaces to the bare finger, nitrile and latex gloves was studied. Then, the transfer of explosive residues from one surface to another through fingerprints was investigated. Cotton fabric (hereinafter referred to as cotton) as clothing material and polycarbonate plastic (hereinafter referred to as polycarbonate) as luggage material were chosen for the experiments. These surfaces containing explosive particles were imaged using a reflex camera before and after the particles were transferred. Afterwards the images were processed in MATLAB where pixels corresponding to explosive residues were quantified. Results demonstrated that transfer of explosive residues frequently occurred with certain differences among materials. Generally, the amount of explosive particles adhered to the finger decreased in the following order: skin>latex>nitrile, while the transfer of particles from the finger to another surface was the opposite. The adhesion of explosive residues from polycarbonate to the finger was found to be better compared to cotton, while the amount of particles transferred to cotton was higher. 相似文献
974.
This paper examines police officer understandings of and attitudes to the sex offenders’ register, Violent and Sex Offenders’ Register (ViSOR) and Child Sexual Offender Disclosure Scheme (CSODS) in England and Wales – an under-researched area in the management of sexual offenders in the UK. This research is an adaptation of an American study utilising a mixed-methods approach, combining an online questionnaire survey (N?=?227) with a series of semi-structured interviews (N?=?27). The study found that police officers, irrespective of role, were generally supportive of the register, ViSOR and CSODS in principle, but they thought that logistics, practicalities, infrastructure, multi-agency collaboration and public understandings had problematic impacts on the scheme in practice. The participants believed that greater investment was needed in terms of time and resource to make the register, ViSOR and CSODS easier to use and access and thus fit for purpose. 相似文献
975.
R.S. Corrêa V.F. Melo G.G.F. Abreu M.H. Sousa J.A. Chaker J.A. Gomes 《Science & justice》2018,58(2):138-144
Soil traces are useful as forensic evidences because they frequently adhere to individuals and objects associated with crimes and can place or discard a suspect at/from a crime scene. Soil is a mixture of organic and inorganic components and among them soil clay contains signatures that make it reliable as forensic evidence. In this study, we hypothesized that soils can be forensically distinguished through the analysis of their clay fraction alone, and that samples of the same soil type can be consistently distinguished according to the distance they were collected from each other. To test these hypotheses 16 Oxisol samples were collected at distances of between 2 m and 1.000 m, and 16 Inceptisol samples were collected at distances of between 2 m and 300 m from each other. Clay fractions were extracted from soil samples and analyzed for hyperspectral color reflectance (HSI), X-ray diffraction crystallographic (XRD), and for contents of iron oxides, kaolinite and gibbsite. The dataset was submitted to multivariate analysis and results were from 65% to 100% effective to distinguish between samples from the two soil types. Both soil types could be consistently distinguished for forensic purposes according to the distance that samples were collected from each other: 1000 m for Oxisol and 10 m for Inceptisol. Clay color and XRD analysis were the most effective techniques to distinguish clay samples, and Inceptisol samples were more easily distinguished than Oxisol samples. Soil forensics seems a promising field for soil scientists as soil clay can be useful as forensic evidence by using routine analytical techniques from soil science. 相似文献
976.
Anita Barbee Corrie Rice Becky F. Antle Katy Henry Michael R. Cunningham 《Journal of public child welfare》2018,12(3):354-379
ABSTRACTThe purpose of the study is to examine the impact of a statewide intervention (BSW level Title IV-E Program) on both the workers’ intent to leave the job and their actual exit from a state administered public child welfare agency. Employees completed an extensive survey including scales assessing individual, team, and organizational variables that might impact turnover. Results show that more Title IV-E graduates stay with the agency than do regular hires and leave at a slower rate. Different variables impact intent to leave compared to actual exit and vary across type of employee. Implications for the workforce are discussed. 相似文献
977.
Troy A. Webber K. Chase Bailey W. Alexander Alverson Edan A. Critchfield Kathleen M. Bain Johanna M. Messerly Justin J. F. O’Rourke Joshua W. Kirton Chrystal Fullen Janice C. Marceaux Jason R. Soble 《Psychological injury and law》2018,11(4):325-335
Assessment of performance validity is an essential part of a neuropsychological evaluation, with the inclusion of two or more performance validity tests (PVTs) becoming routine practice. Considering the time to administer multiple tests, there has been some support for use of the Test of Memory Malingering (TOMM) Trial 1 (T1) as an independent, “one and done” PVT. Notably, cutoffs for TOMM T1 need further validation, with an emphasis on minimizing false-positive classifications among those with bona fide cognitive impairment. In a clinically referred sample of 127 veterans, this study examined the role of cognitive impairment in TOMM performance and the utility of a TOMM T1 as an independent PVT. Examinees were administered the TOMM and three additional PVTs as part of a comprehensive neuropsychological battery. Sixty-eight percent of examinees were classified valid (35% of valid examinees were cognitively impaired). TOMM T1?≤?40 had excellent observed sensitivity (83%) and specificity (93%) overall, with minimal false-positive classification. TOMM T1 was also significantly correlated and concordant with other memory-based PVTs. Given score ranges and failure rates for TOMM T1?≤?40 among those with neurological/neurocognitive conditions, scores in the 37–40 range may merit administration of additional TOMM trials to maximize accuracy in identifying valid-cognitively impaired versus noncredible performance. Otherwise, an abbreviated TOMM administration (i.e., only T1) using a cutoff of ≤?40—in conjunction with one or more additional PVTs—may be sufficient for detecting noncredible/invalid test performance in the absence of known or suspected neurological/neurocognitive disorders. 相似文献
978.
Jerry F. Hough 《后苏联事务》2013,29(4):302-312
Assumptions that major reform in the Soviet economy cannot be realized are challenged. Beliefs that Gorbachev is unable or unwilling to take necessary political risks, that bureaucratic resistance will forestall efforts at incremental change, and that Communist ideology lacks themes that can be used to mobilize support for innovation are analyzed. Assessment of reform should be based on an awareness of the advantages (as well as risks) of a strategy tying Gorbachev's political fate to reform and of the effectiveness of a timetable that consolidates gains in services and agriculture before confronting an entrenched industrial bureaucracy. Journal of Economic Literature, Classification Numbers: 052, 113, 124. 相似文献
979.
980.