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John M. MacDonald 《Justice Quarterly》2019,36(4):656-681
The current study builds on prior research examining racial disparities in sentencing. Entropy weighting is introduced as a new method for estimating racial disparities that has several advantages over traditionally used methods. Entropy weighting is compared to regression and propensity score methods in estimating Black-White disparities in incarceration sentences. Although all methods find non-significant racial disparities in incarceration sentences, regression and propensity score methods underestimate disparities in incarceration sentence lengths. Entropy weighting provides comparable estimates to propensity score methods, but assures that the samples are identical on all covariates aside from race. The method offers researchers a useful and flexible approach for estimating racial disparities in criminal justice, and its use may lead to alternative conclusions about the size and presence of racial disparities in sentencing. 相似文献
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Recently, a sample containing cyclopropylfentanyl was analyzed at this laboratory. Cyclopropylfentanyl began to appear in the United States' illicit drug markets in 2017. Unfortunately, cyclopropylfentanyl presents an analytical challenge due to its mass spectrum being almost identical to that of crotonylfentanyl. There are two possible isomers of crotonylfentanyl, Z- and E- crotonylfentanyl. In order to provide sufficient analytical data to distinguish the two isomers of crotonylfentanyl and cyclopropylfentanyl, crotonylfentanyl was synthesized and fully characterized. Each isomer was analyzed via nuclear magnetic resonance spectroscopy, gas chromatography–mass spectrometry, and Fourier transform infrared spectroscopy. During the synthesis of crotonylfentanyl, an unknown compound was formed. The identification of this compound and the analytical characterization of the two isomers of crotonylfentanyl are presented. Through the comparison of these compounds, it was confirmed that cyclopropylfentanyl can be differentiated from crotonylfentanyl. 相似文献
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This article explores and shares the learning from two of Cafcass’ innovative dispute resolution pilot programs. The programs aim to improve outcomes for families against the backdrop of rising private law demand in England, while keeping the child at the center. The Positive co‐Parenting Programme pilot provides a structured intervention to reduce conflict and promote timely resolution for children and families in complex cases. The Support with Making Child Arrangements pilot explores whether the provision of a package of support to parents ahead of the first court hearing can help them come to safe agreements about their children without the need for court intervention. 相似文献
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The Effectiveness of Trace DNA Profiling—A Comparison Between a U.S. and a U.K. Law Enforcement Jurisdiction 下载免费PDF全文
John W. Bond O.B.E. D.Phil. Jocelyn R. Weart O.B.E. D.Phil. 《Journal of forensic sciences》2017,62(3):753-760
Recovery, profiling, and speculative searching of trace DNA (not attributable to a body fluid/cell type) over a twelve‐month period in a U.S. Crime Laboratory and U.K. police force are compared. Results show greater numbers of U.S. firearm‐related items submitted for analysis compared with the U.K., where greatest numbers were submitted from burglary or vehicle offenses. U.S. multiple recovery techniques (double swabbing) occurred mainly during laboratory examination, whereas the majority of U.K. multiple recovery techniques occurred at the scene. No statistical difference was observed for useful profiles from single or multiple recovery. Database loading of interpretable profiles was most successful for U.K. items related to burglary or vehicle offenses. Database associations (matches) represented 7.0% of all U.S. items and 13.1% of all U.K. items. The U.K. strategy for burglary and vehicle examination demonstrated that careful selection of both items and sampling techniques is crucial to obtaining the observed results. 相似文献
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Quantitative Determination of Cannabinoids in Cannabis and Cannabis Products Using Ultra‐High‐Performance Supercritical Fluid Chromatography and Diode Array/Mass Spectrometric Detection 下载免费PDF全文
Mei Wang Ph.D. Yan‐Hong Wang Ph.D. Bharathi Avula Ph.D. Mohamed M. Radwan Ph.D. Amira S. Wanas Ph.D. Zlatko Mehmedic M.Sc. John van Antwerp B.Sc. Mahmoud A. ElSohly Ph.D. Ikhlas A. Khan Ph.D. 《Journal of forensic sciences》2017,62(3):602-611
Ultra‐high‐performance supercritical fluid chromatography (UHPSFC ) is an efficient analytical technique and has not been fully employed for the analysis of cannabis. Here, a novel method was developed for the analysis of 30 cannabis plant extracts and preparations using UHPSFC /PDA ‐MS . Nine of the most abundant cannabinoids, viz . CBD , ?8‐THC , THCV , ?9‐THC , CBN , CBG , THCA ‐A, CBDA , and CBGA , were quantitatively determined (RSD s < 6.9%). Unlike GC methods, no derivatization or decarboxylation was required prior to UHPSFC analysis. The UHPSFC chromatographic separation of cannabinoids displayed an inverse elution order compared to UHPLC . Combining with PDA ‐MS , this orthogonality is valuable for discrimination of cannabinoids in complex matrices. The developed method was validated, and the quantification results were compared with a standard UHPLC method. The RSD s of these two methods were within ±13.0%. Finally, chemometric analysis including principal component analysis (PCA ) and partial least squares‐discriminant analysis (PLS ‐DA ) were used to differentiate between cannabis samples. 相似文献