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951.
The isotope ratios of amphetamine type stimulants (ATS) depend as well on the precursor as the synthetic pathway. For clandestine production of amphetamine and methamphetamine, 1-phenyl-2-propanone (P2P, benzylmethylketone) is a commonly used precursor.Our aim was to determine the variation of the isotope ratios within precursor samples of one manufacturer and to compare seized samples of unknown sources to these values. δ13CV-PDB, δ2HV-SMOW and δ18OV-SMOW isotope ratios were determined using elemental analysis (EA) and gas chromatography (GC) coupled to an isotope ratio mass spectrometer (IRMS). The comparison of all seized samples to the data of the samples of one manufacturer revealed considerable differences. The results show that IRMS provides a high potential in differentiating between precursors from different manufacturers for the clandestine production of ATS and identifying corresponding sources.  相似文献   
952.
Research Summary Over the past two decades, researchers have been increasingly interested in measuring the risk of offender recidivism as a means of advancing public safety and of directing treatment interventions. In this context, one instrument widely used in assessing offenders is the Level of Service Inventory‐Revised (LSI‐R). Recently, however, the LSI‐R has been criticized for being a male‐specific assessment instrument that is a weak predictor of criminal behavior in females. Through the use of meta‐analytic techniques, we assessed this assertion. A total of 27 effect sizes yielded an average r value of .35 ([confidence interval] CI = .34 to .36) for the relationship of the LSI‐R with recidivism for female offenders (N= 14,737). When available, we also made within‐sample comparisons based on gender. These comparisons produced effect sizes for males and females that were statistically similar. Policy Implications These results are consistent with those generated in previous research on the LSI‐R. They call into question prevailing critiques that the LSI‐R has predictive validity for male but not for female offenders. At this stage, it seems that corrections officials should be advised that the LSI‐R remains an important instrument for assessing all offenders as a prelude to the delivery of treatment services, especially those based on the principles of effective intervention. Critics should be encouraged, however, to construct and validate through research additional gender‐specific instruments that revise, if not rival, the LSI‐R.  相似文献   
953.
Employment status following spinal cord injury (SCI) has important implications for financial and psychosocial well-being. Several age-related variables-in particular chronological age, duration of SCI, and age at SCI onset-have been identified as being associated with employment among individuals with SCI. Cross-sectional investigations of this topic are complicated by methodological and statistical issues associated with aging and disability. The purpose of the current study was to examine the associations between three aging variables and employment status in individuals with SCI through a series of regression analyses. Six hundred twenty individuals with SCI completed a survey that included measures of demographic characteristics, pain, psychological functioning, physical functioning, fatigue, and sleep. The results indicated that chronological age and age at SCI onset were significant predictors of employment status. A significantly greater proportion of individuals aged 45-54 were employed compared to those aged 55-64 even after controlling for biopsychosocial variables. Additionally, there was a negative linear relationship between percent employed and age at SCI onset, and this relationship was not accounted for by the biopsychosocial variables. The analyses used in this study provide one method by which to disentangle the effects of different age-related variables on important SCI outcomes in cross-sectional research. Continued research in this area is needed to better understand age-related effects on employment status, which could be used to help maximize the quality of life in individuals with SCI.  相似文献   
954.
The PCR technique has become a powerful and very sensitive tool in a broad field of research, that is, molecular biology, medical diagnostics, population genetics, ancient DNA analysis and forensic casework.However, the high sensitivity down to single molecules can easily cause false-positive PCR results due to different types of contamination. In this study, artificial DNA contaminations (saliva and pure DNA) were treated with UV irradiation and other decontamination procedures. A satisfactory DNA removal could not be achieved, emphasizing the necessity of contamination avoidance.  相似文献   
955.
956.
What do eyewitness identification experiments typically show? We address this question through a meta-analysis of 94 comparisons between target-present and target-absent lineups. The analyses showed that: (a) correct identifications and correct-nonidentifications were uncorrelated, (b) suspect identifications were more diagnostic with respect to the suspect’s guilt or innocence than any other response, (c) nonidentifications were diagnostic of the suspect’s innocence, (d) the diagnosticity of foil identifications depended on lineup composition, and (e) don’t know responses were nondiagnostic with respect to guilt or innocence. Results of diagnosticity analyses for simultaneous and sequential lineups varied for full-sample versus direct-comparison analyses. Diagnosticity patterns also varied as a function of lineup composition. Theoretical, forensic, and legal implications are discussed.  相似文献   
957.
An actuarial tool, the Ontario Domestic Assault Risk Assessment (ODARA), predicts recidivism using only variables readily obtained by frontline police officers. Correctional settings permit more comprehensive assessments. In a subset of ODARA construction and cross-validation cases, 303 men with a police record for wife assault and a correctional system file, the VRAG, SARA, Danger Assessment, and DVSI also predicted recidivism, but the Hare Psychopathy Checklist (PCL-R) best improved prediction of recidivism, occurrence, frequency, severity, injury, and charges. In 346 new cases, ODARA and PCL-R independently predicted recidivism. An algorithm was derived for a combined instrument, the Domestic Violence Risk Appraisal Guide (DVRAG), and an experience table is presented (N=649). Results indicated the importance of antisociality in wife assault.  相似文献   
958.
The "red zone" usually refers to the first few weeks of the first semester at college, when female students are believed to be at greatest risk for experiencing unwanted sex. We tested this notion using data from a survey study of 207 first-and second-year students (121 women, 84 men) at a small, liberal arts university. Results demonstrated only one significant elevation in incidence rates of first- and second-year women's unwanted sexual experiences (sexual touching, attempted and completed anal, oral, and vaginal sex), between the end of the first month and fall break (mid-October) during the second year at school. Previous research and local information about the relevant behaviors of sorority and fraternity members is discussed in light of these findings to provide heuristic material for further empirical testing. Because risk may involve both temporal and situational factors, systematic collection and dissemination of local data are recommended.  相似文献   
959.
Little attention has been given to repeat violent and sexual victimization among college women. Using two national-level data sets, the authors find that a small proportion of college women experience a large proportion of violent and sexual victimizations. Women are more likely to experience repeat sexual victimization than repeat violence incidents. Repeat victimization tends to happen in the same month of the initial victimization, and the most likely next type of victimization is by far the same type of victimization. Comparing incident-level characteristics of repeat incidents to single incidents, there are few differences, with the exception that, in a larger proportion of single incidents, women took self-protective action. Implications for prevention and educational programs are discussed.  相似文献   
960.
Abstract:  The emergence of drug-resistant tuberculosis (TB) poses a major threat to TB control efforts. We report a case of a 50-year-old man with pulmonary TB. The scene investigation had initially suspected for homicide; however, the result of medico-legal autopsy demonstrated natural cause of death. Statistical data suggest that the rates of national mortality by respiratory TB decreased in the last decades in Hungary; however, an increasing TB mortality was detected in the capital Budapest. Facing a new mortality trend in TB, the forensic scene investigation and determination of manner of death represent new challenges for practitioners.  相似文献   
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