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831.
Hwan Young Lee Ph.D. Na Young Kim M.S. Myung Jin Park M.S. Jeong Eun Sim B.S. Woo Ick Yang Ph.D. Kyoung‐Jin Shin Ph.D. 《Journal of forensic sciences》2010,55(6):1422-1429
Abstract: The identification of missing casualties of the Korean War (1950–1953) has been performed using mitochondrial DNA (mtDNA) profiles, but recent advances in DNA extraction techniques and approaches using smaller amplicons have significantly increased the possibility of obtaining DNA profiles from highly degraded skeletal remains. Therefore, 21 skeletal remains of Korean War victims and 24 samples from biological relatives of the supposed victims were selected based on circumstantial evidence and/or mtDNA‐matching results and were analyzed to confirm the alleged relationship. Cumulative likelihood ratios were obtained from autosomal short tandem repeat, Y‐chromosomal STR, and mtDNA‐genotyping results, and mainly confirmed the alleged relationship with values over 105. The present analysis emphasizes the value of mini‐ and Y‐STR systems as well as an efficient DNA extraction method in DNA testing for the identification of old skeletal remains. 相似文献
832.
A gas chromatography–mass spectrometry (GC–MS) method was developed and validated for the simultaneous qualification and quantification of methamphetamine (MA), amphetamine (AP), 3,4-methylenedioxy-N-methylamphetamine (MDMA), 3,4-methylenedioxy-N-amphetamine (MDA), ketamine (KET) and norketamine (NKT) in fingernails. Fingernail samples (20 mg) were washed with distilled water and methanol, digested with 1.0 M sodium hydroxide at 95 °C for 30 min, and then extracted with ethyl acetate. Extract solutions were evaporated to dryness, derivatized using heptafluorobutyric anhydride (HFBA) at 60 °C for 30 min, and analyzed by GC–MS. The linear ranges were 0.1–20.0 ng/mg for AP, MDMA and NKT, 0.2–20.0 ng/mg for MA and MDA, and 0.4–20.0 ng/mg for KET, with the coefficients of determination (r2 ≥ 0.9989). The intra- and inter-day precisions were within 7.1% and 10.6%, respectively. The intra- and inter-day accuracies were ?10.9% to 0.8% and ?4.3% to 4.5%, respectively. The limits of detections (LODs) and the limits of quantifications (LOQs) for each analyte were lower than 0.094 ng/mg and 0.314 ng/mg, respectively. The recoveries were in the range of 72.3–94.9%. The average fingernail growth rates of two subjects for three years and six subjects for two months were 3.12 mm/month and 3.16 mm/month, respectively. The method proved to be suitable also for the simultaneous detection and quantification of MA, MDMA, KET and their metabolites in fingernails. 相似文献
833.
Hwan Young Lee Myung Jin Park Na Young Kim Jeong Eun Sim Woo Ick Yang Kyoung-Jin Shin 《Forensic Science International: Genetics Supplement Series》2010,4(5):275-280
The recovery of DNA data from old skeletal remains is often difficult due to degraded and very low yield of extracted DNA and the presence of PCR inhibitors. Herein, we compared several silica-based DNA extraction methods from artificially degraded DNA, DNA with PCR inhibitors and DNA from old skeletal remains using quantitative real-time PCR. We present a modified large-scale silica-based extraction combined with complete demineralization, that enables maximum DNA recovery and efficient elimination of PCR inhibitors. This is performed with high concentration of EDTA solution for demineralization of bone powder followed by QIAamp® spin columns and buffers from the QIAquick® PCR purification kit. We have successfully used this modified technique to perform STR analysis for 55-year-old skeletal remains. The results of this study will contribute to solve the forensic cases dealing with skeletal remains. 相似文献
834.
Cannabis sales by youth gangs consisting of male descendants of immigrants from Middle Eastern countries are subject of much public debate in Denmark and Scandinavia. Only little research has explored the intersection between the wider social context of the drug market and the criminal engagements of these groups using qualitative methods. Using eleven semi-structured interviews with youth, police and experts, collected between 2011 and 2013, this study examines how the overall structure of the cannabis market in Copenhagen affects the opportunities to engage in cannabis sales for immigrant youth gangs. The study rests on an assumption that increased deterrence in specific geographic areas will displace buyers and shift market shares between competing groups. The result was that increased cannabis dealing furthered gang evolution even at the lowest organizational steps, from neighbourhood groups to more delinquent collectives. A key finding is that neighbourhood youth clubs play a central role in the lives of the interviewees. Youth clubs served as social spaces but also functioned as a form of turf to be conquered from city officials. 相似文献
835.
Objectives
We argue that assessing the level of crime concentration across cities has four challenges: (1) how much variability should we expect to observe; (2) whether concentration should be measured across different types of macro units of different sizes; (3) a statistical challenge for measuring crime concentration; (4) the temporal assumption employed when measuring high crime locations.Methods
We use data for 42 cities in southern California with at least 40,000 population to assess the level of crime concentration in them for five different Part 1 crimes and total Part 1 crimes over 2005–2012. We demonstrate that the traditional measure of crime concentration is confounded by crimes that may simply spatially locate due to random chance. We also use two measures employing different temporal assumptions: a historically adjusted crime concentration measure, and a temporally adjusted crime concentration measure (a novel approximate solution that is simple for researchers to implement).Results
There is much variability in crime concentration over cities in the top 5 % of street segments. The standard deviation across cities over years for the temporally adjusted crime concentration measure is between 10 and 20 % across crime types (with the average range typically being about 15–90 %). The historically adjusted concentration has similar variability and typically ranges from about 35 to 100 %.Conclusions
The study provides evidence of variability in the level of crime concentration across cities, but also raises important questions about the temporal scale when measuring this concentration. The results open an exciting new area of research exploring why levels of crime concentration may vary over cities? Either micro- or macro- theories may help researchers in exploring this new direction.836.
837.
This study examines how creditors in illicit drug markets manage debtors’ inability to repay “fronted” drugs. Based on qualitative interviews with 40 incarcerated drug dealers in Norway, we explore four outcomes of unpaid drug debts. Two modes of governance dominated the credit reciprocation processes: Cooperative governance included strategies of accepting loss and refinancing debt and required mutual trust between creditor and debtor. Adversarial governance included extortion of debtors and revenge and was based on threats of violence. We found that creditors preferred refinancing debt or extorting debtors over accepting loss or using violence. We argue that the negotiated outcomes of drug debt have been neglected in research on drug markets, and explore how they require investment from the creditor, either in building trust or in deterring malfeasance through threats of violence. Using insights from economic sociology, the study highlights the importance of social control in illegal drug markets. 相似文献
838.
839.
Within a social learning model, family-of-origin violence places men at risk for developing negative communication in their adult relationships. Thirty young men exposed to family-of-origin violence (exposed group) and 30 unexposed young men were videotaped discussing a conflict topic with their female dating partners. Relative to the unexposed group, the exposed men and women reported higher relationship aggression and during discussion showed more negative communication, were more domineering, and the men reported more negative affect. There were no differences between the groups on cognition or heart rate. The conflict management deficits and aggression evident in the exposed group suggest that these partners are at high risk for future relationship aggression and distress. 相似文献
840.
Kacinko SL Barnes AJ Kim I Moolchan ET Wilson L Cooper GA Reid C Baldwin D Hand CW Huestis MA 《Forensic science international》2004,141(1):41-48
Oral fluid is an interesting alternative matrix for drug testing in many environments, including law enforcement, workplace drug testing, and drug treatment facilities. Performance characteristics of the FDA-cleared, qualitative, Cozart RapiScan Opiate Oral Fluid Drug Testing System (Opiate Cozart RapiScan System or Opiate CRS) were compared to the semi-quantitative Cozart Microplate EIA Opiate Oral Fluid Kit (Opiate ELISA) and to gas chromatography/mass spectrometry (GC/MS). The following oral fluid opiate cutoffs were evaluated: the GC/MS limit of quantification (LOQ) of 2.5 mg/l; 15 microg/l currently used for oral fluid testing in the United Kingdom (UK); 30 microg/l (Opiate CRS cutoff); and 40 microg/l, the proposed Substance Abuse and Mental Health Services Administration (SAMHSA) cutoff. Subjects provided informed consent to participate in this IRB-approved research and resided on the closed research ward throughout the study. Three oral codeine doses of 60 mg/70 kg were administered over a 7-day period. After a 3-week break, subjects received three doses of 120 mg/70 kg within 7 days. Oral fluid specimens (N = 1273) were analyzed for codeine (COD), norcodeine (NCOD), morphine (MOR) and normorphine (NMOR) by GC/MS with an LOQ of 2.5 microg/l for all analytes. MOR and NMOR were not detected in any sample; 26.5% of the specimens were positive for COD and 13.7% for NCOD. Opiate CRS uses a preset, qualitative cutoff of 10 microg/l; this is equivalent to 30 microg/l in undiluted oral fluid as the oral fluid collection process involves a 1:3 dilution with buffer. Sensitivity, specificity, and efficiency of Opiate CRS compared to Opiate ELISA were 98.6, 98.1, and 98.2% at a 30 microg/l cutoff and 99.0, 96.2, and 96.6% at a 40 microg/l cutoff. Compared to the much lower GC/MS LOQ of 2.5 microg/l, sensitivity, specificity and efficiency were 66.8, 99.3 and 90.7%. Increasing the GC/MS cutoff to the current UK level yielded performance characteristics of 81.5% (sensitivity), 99.3% (specificity), and 95.4% (efficiency). Using a GC/MS cutoff identical to the preset Opiate CRS cutoff yielded sensitivity, specificity, and efficiency of 88.5, 99.2, and 97.5%, respectively. At the proposed SAMSHA confirmation cutoff of 40 microg/l, sensitivity increased with little change in specificity and efficiency (91.3% sensitivity, 98.9% specificity, and 97.5% efficiency). Oral fluid is a suitable matrix for detecting drugs of abuse. Opiate CRS, with a 30 microg/l cutoff, is sufficiently sensitive, specific and efficient for oral fluid opiate analysis, performing similarly to Opiate ELISA at the same cutoff, and having performance characteristics >91% when compared to GC/MS at the proposed SAMHSA cutoff. 相似文献