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921.
Preliminary Validation of Handheld X‐Ray Fluorescence Spectrometry: Distinguishing Osseous and Dental Tissue from Nonbone Material of Similar Chemical Composition
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Heather A. Zimmerman M.A. John J. Schultz Ph.D. Michael E. Sigman Ph.D. 《Journal of forensic sciences》2015,60(2):382-390
One of the tasks of a forensic anthropologist is to sort human bone fragments from other materials, which can be difficult when dealing with highly fragmented and taphonomically modified material. The purpose of this research is to develop a method using handheld X‐ray fluorescence (HHXRF) spectrometry to distinguish human and nonhuman bone/teeth from nonbone materials of similar chemical composition using multivariate statistical analyses. The sample materials were derived primarily from previous studies: human bone and teeth, nonhuman bone, nonbiological materials, nonbone biological materials, and taphonomically modified materials. The testing included two phases, testing both the reliability of the instrument and the accuracy of the technique. The results indicate that osseous and dental tissue can be distinguished from nonbone material of similar chemical composition with a high degree of accuracy (94%). While it was not possible to discriminate rock apatite and synthetic hydroxyapatite from bone/teeth, this technique successfully discriminated ivory and octocoral. 相似文献
922.
David Campbell 《The Modern law review》2015,78(2):296-323
The attempt to combine the contractual interests properly so‐called with the restitution interest in the Fuller and Purdue three interests model of remedies for breach of contract is ineradicably incoherent. Stimulated by reflection on contemporary restitution doctrine's understanding of the quasi‐contractual remedies of recovery and quantum meruit, this paper argues that the complete elimination from the law of contract of the restitution interest, which incorporates those remedies into the three interests model, would improve both the coherence of the model of contractual interests and the substantive law of remedies for breach. 相似文献
923.
Distribution of ∆9‐Tetrahydrocannabinol and 11‐Nor‐9‐Carboxy‐∆9‐Tetrahydrocannabinol Acid in Postmortem Biological Fluids and Tissues From Pilots Fatally Injured in Aviation Accidents
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Philip M. Kemp Ph.D. Patrick S. Cardona B.S. Arvind K. Chaturvedi Ph.D. John W. Soper Ph.D. 《Journal of forensic sciences》2015,60(4):942-949
Little is known of the postmortem distribution of ?9‐tetrahydrocannabinol (THC) and its major metabolite, 11‐nor‐9‐carboxy‐?9‐tetrahydrocannabinol (THCCOOH). Data from 55 pilots involved in fatal aviation accidents are presented in this study. Gas chromatography/mass spectrometry analysis obtained mean THC concentrations in blood from multiple sites, liver, lung, and kidney of 15.6 ng/mL, 92.4 ng/g, 766.0 ng/g, 44.1 ng/g and mean THCCOOH concentrations of 35.9 ng/mL, 322.4 ng/g, 42.6 ng/g, 138.5 ng/g, respectively. Heart THC concentrations (two cases) were 184.4 and 759.3 ng/g, and corresponding THCCOOH measured 11.0 and 95.9 ng/g, respectively. Muscle concentrations for THC (two cases) were 16.6 and 2.5 ng/g; corresponding THCCOOH, “confirmed positive” and 1.4 ng/g. The only brain tested in this study showed no THC detected and 2.9 ng/g THCCOOH, low concentrations that correlated with low values in other specimens from this case. This research emphasizes the need for postmortem cannabinoid testing and demonstrates the usefulness of a number of tissues, most notably lung, for these analyses. 相似文献
924.
Fei Deng Ph.D. Xiaodong Lin M.L. Yonghong He Ph.D. Shu Li M.L. Run Zi B.Sc. Shijun Lai B.E. 《Journal of forensic sciences》2015,60(4):1040-1045
Quantitative phase analysis (QPA) is helpful to determine the type attribute of the object because it could present the content of the constituents. QPA by Rietveld method requires neither measurement of calibration data nor the use of an internal standard; however, the approximate crystal structure of each phase in a mixture is necessary. In this study, 8 synthetic mixtures composed of potassium nitrate and sulfur were analyzed by Rietveld QPA method. The Rietveld refinement was accomplished with a material analysis using diffraction program and evaluated by three agreement indices. Results showed that Rietveld QPA yielded precise results, with errors generally less than 2.0% absolute. In addition, a criminal case which was broken successfully with the help of Rietveld QPA method was also introduced. This method will allow forensic investigators to acquire detailed information of the material evidence, which could point out the direction for case detection and court proceedings. 相似文献
925.
Elemental Analysis of Variably Contaminated Cremains Using X‐ray Fluorescence Spectrometry
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Analyzing and identifying skeletal remains becomes increasingly difficult when remains have been cremated, especially in cases where the cremated material may have been intentionally contaminated with nonskeletal material. This study examined the potential of X‐ray fluorescence spectrometry (XRF) to detect the presence of nonskeletal contaminants in samples of cremains. Eleven samples of cremains were variably combined with concrete mix and analyzed using XRF. Photon counts of elements in each sample were analyzed, and the coefficient of determination (R2) using unweighted linear regression as a function of percent cremains was calculated. Results showed that with changes in the proportion of skeletal material and contaminant, there were significant (R2 > 0.90) changes in detected levels of phosphorus, potassium, zinc, aluminum, and sulfur. The use of XRF is concluded to be a valid approach in the identification of the presence of nonskeletal material in potentially contaminated cremains. 相似文献
926.
Parent and Metabolite Opioid Drug Concentrations in Unintentional Deaths Involving Opioid and Benzodiazepine Combinations,,
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Marcia D. Fields Pharm.D. Marie A. Abate B.S. Pharm.D. Lan Hu B.S.N. D. Leann Long Ph.D. Matthew L. Blommel Pharm.D. Nabila A. Haikal M.D. James C. Kraner Ph.D. 《Journal of forensic sciences》2015,60(4):950-956
Effects of benzodiazepines on postmortem opioid parent and parent/metabolite blood concentration ratios were determined for fentanyl‐, hydrocodone‐, methadone‐, or oxycodone‐related accidental deaths. These opioids are partially metabolized by the CYP3A4 enzyme system, which is also affected by diazepam and alprazolam. Opioid/metabolite combinations examined were as follows: fentanyl/norfentanyl, hydrocodone/dihydrocodeine, methadone/EDDP, and oxycodone/oxymorphone. Parent opioid concentrations were analyzed for 877 deaths. Parent/metabolite concentration ratios were analyzed for 349 deaths, excluding cases with co‐intoxicants present known to interfere with opioid elimination. Alprazolam in combination with diazepam significantly decreased median hydrocodone concentrations by 48% (p = 0.01) compared to hydrocodone alone. The methadone parent/metabolite concentration ratio was reduced by 35% in the presence of diazepam compared to methadone alone (p = 0.03). Benzodiazepines did not statistically significantly affect fentanyl or oxycodone concentrations. Possible factors affecting opioid concentrations and possible toxicity development, including any differential effects on specific opioids, should continue to be explored. 相似文献
927.
Identification of 2‐(ethylamino)‐1‐(4‐methylphenyl)‐1‐pentanone (4‐MEAP), a New “Legal High” Sold by an Internet Vendor as 4‐Methyl Pentedrone
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Danielle Hamby M.Sc. Annessa Burnett B.S. Michael Jablonsky Ph.D. Brendan Twamley Ph.D. Pierce V. Kavanagh Ph.D. Elizabeth A. Gardner Ph.D. 《Journal of forensic sciences》2015,60(3):721-726
Online vendors are offering a new legal high, 4‐methylpentedrone (4‐MPD). Information for potential users provided by internet vendors of 4‐MPD includes incorrect structures and nonexistent CAS numbers. A sample of 4‐MPD was obtained and analyzed using GC‐MS, NMR, and LC‐EIS. The fragmentation data from the GC‐MS and LC‐EIS produced an M‐1 ion that suggested the molecular mass was 219 amu, rather than 205 amu as calculated for 4‐methylpentedrone. The difference in molecular mass corresponded to the addition of a methyl group. Based on the mass and fragmentation pattern, two standards were synthesized, 2‐(ethylamino)‐1‐(4‐methylphenyl)‐1‐pentanone and 1‐(4‐methylphenyl)‐2‐(propylamino)‐1‐butanone. The synthesis involved bromination of the appropriate ketone followed by the reaction with ethylamine or propylamine. Based on the NMR data and unique fragmentation patterns produced by these molecules, the sample was identified as 2‐(ethylamino)‐1‐(4‐methylphenyl)‐1‐pentanone, not 4‐methylpentedrone. 相似文献
928.
The Effects of Dextromethorphan on Driving Performance and the Standardized Field Sobriety Test
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Paul J. Perry B.Pharm. Ph.D. Kristian Fredriksen B.A. Stephanie Chew B.A. Eric J. Ip Pharm.D. Ingrid Lopes D.O. Shadi Doroudgar Pharm.D. Kelan Thomas Pharm.D. M.S. 《Journal of forensic sciences》2015,60(5):1258-1262
Dextromethorphan (DXM) is abused most commonly among adolescents as a recreational drug to generate a dissociative experience. The objective of the study was to assess driving with and without DXM ingestion. The effects of one‐time maximum daily doses of DXM 120 mg versus a guaifenesin 400 mg dose were compared among 40 healthy subjects using a crossover design. Subjects’ ability to drive was assessed by their performance in a driving simulator (STISIM® Drive driving simulator software) and by conducting a standardized field sobriety test (SFST) administered 1‐h postdrug administration. The one‐time dose of DXM 120 mg did not demonstrate driving impairment on the STISIM® Drive driving simulator or increase SFST failures compared to guaifenesin 400 mg. Doses greater than the currently recommended maximum daily dose of 120 mg are necessary to perturb driving behavior. 相似文献
929.
Evaluating Simulant Materials for Understanding Cranial Backspatter from a Ballistic Projectile
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Raj Das Ph.D. Alistair Collins B.E. Anurag Verma B.E. Justin Fernandez Ph.D. Michael Taylor Ph.D. 《Journal of forensic sciences》2015,60(3):627-637
In cranial wounds resulting from a gunshot, the study of backspatter patterns can provide information about the actual incidents by linking material to surrounding objects. This study investigates the physics of backspatter from a high‐speed projectile impact and evaluates a range of simulant materials using impact tests. Next, we evaluate a mesh‐free method called smoothed particle hydrodynamics (SPH) to model the splashing mechanism during backspatter. The study has shown that a projectile impact causes fragmentation at the impact site, while transferring momentum to fragmented particles. The particles travel along the path of least resistance, leading to partial material movement in the reverse direction of the projectile motion causing backspatter. Medium‐density fiberboard is a better simulant for a human skull than polycarbonate, and lorica leather is a better simulant for a human skin than natural rubber. SPH is an effective numerical method for modeling the high‐speed impact fracture and fragmentations. 相似文献
930.
A Rigorous Quasi‐Experimental Design to Evaluate the Causal Effect of a Mandatory Divorce Education Program
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All couples with minor children who filed for divorce within a specific 6‐week period (N = 191 couples) in one jurisdiction were ordered to attend a divorce education program. The control group included about 20 couples randomly selected from each of six 6‐week intervals before and six 6‐week intervals after the treatment interval (N = 243 couples). Archival records were searched for variables such as legal and residential custody award, visitation percentage, and relitigation. The impact of the program was assessed by evaluating, for each variable, whether the data for program interval departed from the straight (regression) line drawn through all the control group intervals. Only the visitation time award significantly differed: 27.75% for treatment couples and 22.46% for control couples. Analyses show that the father's attendance at the program primarily accounts for the difference.
- Key Points for the Family Court Community
- There are considerable methodological weaknesses in most of the existing evaluations of divorcing parent education programs.
- Stronger, more scientifically rigorous—and thus persuasive—designs are possible in court settings, such as the regression discontinuity quasi‐experimental design we feature here.
- Archival records, such as various court filings, are a rich and relatively untapped source of data.
- Being mandated to attend a single 2‐hour divorcing parent education class caused an increase in the visitation time award in divorce decrees.
- There is a disconnect between being mandated by a judge to attend a program and actual attendance.