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971.
Modeling Bone Surface Morphology: A Fully Quantitative Method for Age‐at‐Death Estimation Using the Pubic Symphysis
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Dennis E. Slice Ph.D. Bridget F. B. Algee‐Hewitt Ph.D. 《Journal of forensic sciences》2015,60(4):835-843
The pubic symphysis is widely used in age estimation for the adult skeleton. Standard practice requires the visual comparison of surface morphology against criteria representing predefined phases and the estimation of case‐specific age from an age range associated with the chosen phase. Known problems of method and observer error necessitate alternative tools to quantify age‐related change in pubic morphology. This paper presents an objective, fully quantitative method for estimating age‐at‐death from the skeleton, which exploits a variance‐based score of surface complexity computed from vertices obtained from a scanner sampling the pubic symphysis. For laser scans from 41 modern American male skeletons, this method produces results that are significantly associated with known age‐at‐death (RMSE = 17.15 years). Chronological age is predicted, therefore, equally well, if not, better, with this robust, objective, and fully quantitative method than with prevailing phase‐aging systems. This method contributes to forensic casework by responding to medico‐legal expectations for evidence standards. 相似文献
972.
Anna A. Mapes M.Sc. Ate D. Kloosterman Ph.D. Christianne J. de Poot Ph.D. 《Journal of forensic sciences》2015,60(4):851-856
Current figures on the efficiency of DNA as an investigative tool in criminal investigations only tell part of the story. To get the DNA success story in the right perspective, we examined all forensic reports from serious (N = 116) and high‐volume crime cases (N = 2791) over the year 2011 from one police region in the Netherlands. These data show that 38% of analyzed serious crime traces (N = 384) and 17% of analyzed high‐volume crime traces (N = 386) did not result in a DNA profile. Turnaround times (from crime scene to DNA report) were 66 days for traces from serious crimes and 44 days for traces from high‐volume crimes. Suspects were truly identified through a match with the Offender DNA database of the Netherlands in 3% of the serious crime cases and in 1% of the high‐volume crime cases. These data are important for both the forensic laboratory and the professionals in the criminal justice system to further optimize forensic DNA testing as an investigative tool. 相似文献
973.
Reproducibility of Facial Soft Tissue Thickness Measurements Using Cone‐Beam CT Images According to the Measurement Methods
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974.
Study of the Behaviors of Gunshot Residues from Spent Cartridges by Headspace Solid‐Phase Microextraction–Gas Chromatographic Techniques
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Kah Haw Chang B.Sc. Chong Hooi Yew Ph.D. Ahmad Fahmi Lim Abdullah Ph.D. 《Journal of forensic sciences》2015,60(4):869-877
Gunshot residues, produced after shooting activity, have acquired their importance in analysis due to the notoriety of firearms‐related crimes. In this study, solid‐phase microextraction was performed to extract the headspace composition of spent cartridges using 85‐μm polyacrylate fiber at 66°C for 21 min. Organic compounds, that is, naphthalene, 2,6‐dinitrotoluene, 2,4‐dinitrotoluene, diphenylamine, and dibutyl phthalate were detected and analyzed by gas chromatography‐flame ionization detection technique. Evaluation of chromatograms for diphenylamine, dibutyl phthalate, and naphthalene indicates the period after a gunshot was discharged, whether it was 1 days, 2–4 days, <5 days, 10 days, 20 days, or more than 30 days ago. This study revealed the potential effects of environmental factors such as occasional wind blow and direct sunlight on the estimation of time after spent cartridges were discharged. In conclusion, we proposed reliable alternative in analyzing the headspace composition of spent cartridges in a simulated crime scene. 相似文献
975.
John M. Starbuck Ph.D. Ahmed Ghoneima Ph.D. Katherine Kula DMD 《Journal of forensic sciences》2015,60(2):274-284
Cleft lip and palate (CLP) is a craniofacial malformation affecting more than seven million people worldwide that results in defects of the hard palate, teeth, maxilla, nasal spine and floor, and maxillodental asymmetry. CLP facial soft‐tissue depth (FSTD) values have never been published. The purpose of this research is to report CLP FSTD values and compare them to previously published FSTD values for normal children. Thirty‐eight FSTDs were measured on cone beam computed tomography images of CLP children (n = 86; 7–17 years). MANOVA and ANOVA tests determined whether cleft type, age, sex, and bone graft surgical status affect tissue depths. Both cleft type (unilateral/bilateral) and age influence FSTDs. CLP FSTDs exhibit patterns of variation that differ from normal children, particularly around the oronasal regions of the face. These differences should be taken into account when facial reconstructions of children with CLP are created. 相似文献
976.
Maurice Olderiks B.Sc. Martin Baiker Ph.D. Jill van Velzen B.Sc. Jaap van der Weerd Ph.D. 《Journal of forensic sciences》2015,60(2):428-434
Manual recovery of spray paints from textiles using a microscope, the routine method in many laboratories, is often laborious. Beating the clothing with a plastic rod, the routine method used for recovery of glass traces within the authors’ laboratory, is proposed as an alternative. The efficiency of the method was evaluated by spray tests with fluorescent paint. In these tests, paint particles in the acquired debris samples, as well as those remaining on the textiles, were investigated. The results show that beating is an efficient way to recover and concentrate paint particles. A good efficiency for jeans fabric and rough knitwear is reported. The results appeared to be less satisfactory for smooth woven fabric. Application of the method in casework was effective for graffiti paints as well as for flaked car paint. 相似文献
977.
Detecting Submerged Bodies: Controlled Research Using Side‐Scan Sonar to Detect Submerged Proxy Cadavers
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Carrie A. Healy M.A. John J. Schultz Ph.D. Kenneth Parker A.A. Bim Lowers B.S. 《Journal of forensic sciences》2015,60(3):743-752
Forensic investigators routinely deploy side‐scan sonar for submerged body searches. This study adds to the limited body of literature by undertaking a controlled project to understand how variables affect detection of submerged bodies using side‐scan sonar. Research consisted of two phases using small and medium‐sized pig (Sus scrofa) carcasses as proxies for human bodies to investigate the effects of terrain, body size, frequency, swath width, and state of decomposition. Results demonstrated that a clear, flat, sandy pond floor terrain was optimal for detection of the target as irregular terrain and/or vegetation are major limitations that can obscure the target. A higher frequency towfish was preferred for small bodies, and a 20 m swath width allowed greater visibility and easier maneuverability of the boat in this environment. Also, the medium‐sized carcasses were discernable throughout the 81‐day study period, indicating that it is possible to detect bodies undergoing decomposition with side‐scan sonar. 相似文献
978.
Hiroto Kawashima Ph.D. 《Journal of forensic sciences》2015,60(5):1360-1364
Between December 2007 and January 2008, people suffered from food poisoning in the Japanese prefectures of Chiba and Hyogo after eating frozen dumplings (gyoza) produced in China, which had very high concentrations (1490–19,290 ppm) of methamidophos (O,S‐dimethyl phosphoramidothioate). Thus, we measured the stable carbon isotope ratio of methamidophos using GC/C/IRMS to identify the source. We analyzed seven methamidophos reagents and one Chinese agricultural methamidophos chemical (MTD600) that contained many impurities. The δ13C values of the seven methamidophos reagents and MTD600 ranged from ?49.23‰ to ?31.90‰, with an average SD of 0.20‰, very high precision. This difference (17.33‰) was very large compared with that in previous reports and may be attributable to the material itself and the chemical processing of methamidophos. Criminals can easily obtain pesticides such as methamidophos; therefore, it is very important to identify the pesticide source and distribution route using stable isotopic science in the future. 相似文献
979.
Symptom Checklist‐90‐Revised Scores in Adult Children Exposed to Alienating Behaviors: An Italian Sample
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William Bernet M.D. Amy J. L. Baker Ph.D. Maria C. Verrocchio Psy.D. 《Journal of forensic sciences》2015,60(2):357-362
This study addresses a particular form of child psychological maltreatment, exposing a child to alienating behaviors in the context of a high degree of conflict between the parents. The objective of this research was to identify retrospectively the alienating behaviors that occurred in an Italian sample of children and the reported associated psychosocial symptoms. Seven hundred and thirty‐nine adults in Chieti, Italy, completed an anonymous and confidential survey regarding their childhood exposure to parental alienating behaviors and measures of current symptomatology. About 75% of the sample reported some exposure to parental alienating behaviors; 15% of the sample endorsed the item, “tried to turn me against the other parent.” The results revealed strong and statistically significant associations between reported exposure to parental alienating behaviors and reports of current symptomatology. 相似文献
980.
The Relationship Between the Surface Morphology and Chemical Composition of Gunshot Residue Particles
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Ilker Kara Ph.D. Sefer Bora Lisesivdin Ph.D. Mehmet Kasap Ph.D. Elif Er PG.Dip. Ugur Uzek B.Sc. 《Journal of forensic sciences》2015,60(4):1030-1033
In this study, chemical composition and morphology of gunshot residue (GSR) of 9 × 19 mm Parabellum‐type MKE (Turkey)‐brand ammunition were analyzed by scanning electron microscope and energy dispersive X‐ray spectrometer. GSR samples were collected by “swab” technique from the shooter's right hand immediately after shooting. According to general principles of thermodynamics, it is likely that the structures will have a more regular (homogeneous) spherical form to minimize their surface area due to very high temperatures and pressures that occur during explosion. Studied samples were collected under the same conditions with the same original ammunition, from the same firearm and a single shooter. This is because many other variables may affect size, structure, and composition in addition to the concentrations of elements of the structure. Results indicated that the chemical compositions are effective in the formation of GSR morphological structures. 相似文献