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The recent emergence of a new class of piperazine-type compounds has brought about the need for laboratory screening methods for both seized drugs and toxicological samples. These piperazine compounds, which include 1-benzylpiperazine (BZP) and 1-(3-trifluoromethylphenyl)piperazine (TFMPP), exhibit comparable physiological effects and can be substituted for the classic amphetamine-type drugs. We have optimized a chiral capillary electrophoresis (CE) separation that detects a set of 6 piperazine and 4 chiral amphetamine compounds in under 23 min using a 200 mM phosphate buffer at a pH = 2.8 with 20 mM hydroxypropyl- beta-cyclodextrin (HPbeta3CD). In addition to the above compounds, a series of "clandestine" BZP diHCl samples were also analyzed using this method to assess the ruggedness of the procedure. The novel CE separation was tailored to simultaneously detect these piperzine compounds in addition to amphetamine-type drugs. Distinct migration time and UV-spectral data were obtained for all compounds of interest.  相似文献   
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OBJECTIVE: Examine factors related to prison suicides to aid prevention. METHOD: Review the mental health records of all 76 suicides that occurred between 1993 and 2001 in New York State Department of Correctional Services (NYSDOCS) prisons that had some contact with mental health services during their incarceration. (This represented 84% of all NYSDOCS suicides.) Extract data from the psychological autopsies for a sample of 40 of these suicides. RESULTS: Of the suicide victims with some mental health contact, 95% had a substance abuse history, 70% displayed agitation or anxiety prior to the suicide, and 48% had a behavioral change. Common stressors preceding the suicide were inmate-to-inmate conflict (50%), recent disciplinary action (42%), fear (40%), physical illness (42%), and adverse information (65%) such as loss of good time or disruption of family/friendship relationships in the community. Forty-one percent had received a mental health service within 3 days of the suicide. Compared to the about 7200 inmates actively receiving mental health services in state prison, African-Americans and patients with a Major Mood (Bi-polar or Major Depression) were under-represented. Adjustment Disorder, Schizophrenia, and Personality Disorder diagnoses were over-represented. Suicide victims were more likely to have been incarcerated for a violent crime. CONCLUSION: Mental illness, anxiety/agitation, behavior change, stressors, history of substance abuse, and non-African-American were important risk factors.  相似文献   
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Reconstructing traumatic thoracic events, especially when soft tissues are absent, requires an advanced understanding of ribcage fracture patterns. The morphology and orientation of ribs complicate the fracture pattern, as a single blow often causes multiple fractures at various locations. Furthermore, fracture types observed in ribs are not explained easily by current bone biomechanic literature. Using evidential skeletal material archived at the Regional Forensic Center, Memphis, the ribs of 43 blunt force trauma cases were analyzed. A total of 195 incomplete fractures and 63 buckle fractures were noted. Incomplete fractures, previously thought to be common in children but rare in adults, were found among individuals ranging in age from 21-76 years. A buckle fracture, failure resulting from compressive instability, has been undefined previously in bone trauma literature but was repeatedly observed in this sample. This study elucidates recognizable rib fracture patterns while emphasizing gross bone examination for force and mechanical factors.  相似文献   
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The Y-PLEX 6 and Y-PLEX 5 systems enable analysis for 11 Y-STR loci. We present here the utility of these systems in forensic casework. A total of 188 samples, including 127 evidence samples, were analyzed using either or both of the systems. The evidence sample types included fingernail scrapings, sperm or seminal fluid, epithelial cells, blood and other tissues. The Y-STR typing systems provided useful probative results in difficult cases. A reference database for Caucasian (n = 517), African American (n = 535), and Hispanic (n = 245) population groups within the United States was generated for estimating the haplotype frequency in forensic casework. Among the individuals profiled, 311 Caucasians, 412 African Americans, and 194 Hispanics provided unique profiles in their respective population datasets. This is the first report describing the haplotype database for the set of 11 Y-STR loci recommended by the Scientific Working Group on DNA Analysis Methods (SWGDAM). Linkage analysis reveals that the frequencies from forensically important autosomal loci can be multiplied with the Y-STR haplotype frequency. The results from Y-PLEX systems have been accepted in courts in the United States.  相似文献   
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A powerful method for validating a scientific result is to confirm specific results utilizing independent methodologies and processing pathways. Thus, we have designed, developed and validated an automated allele concordance analysis system (CompareCalls, patent pending) that performs comparisons between two independent DNA analysis platforms to ensure the highest accuracy for allele calls. Application of this system in a quality assurance role has shown the potential to eliminate greater than 90% of the STR analysis required of a DNA data analyst. While this system is broadly applicable for use with any two independent STR analysis programs, either prior to or following human data review, we are presenting its application to data generated with the ABI Prism Genotyper software system versus data generated with the SurelockID system. With the automated allele concordance analysis system, the GeneScan DNA fragment data generated from an ABI 377 gel image are analyzed in two independent pathways. In one analysis pathway, the GeneScan data are imported into Genotyper software where STR labels are assigned to the fragment data based upon the criteria of the Kazam 20% macro. The "Kazam" macro provided with the Genotyper program works by labeling all peaks in a category (or locus) and then filtering (or removing) the labels from peaks, such as those in stutter positions, that meet predefined criteria. In the second pathway, the GeneScan data are imported into the SurelockID analysis platform where STR labels and error messages are assigned to the fragment data based upon hard-coded allele calling criteria and quality parameters. The resulting STR allele calls for each analysis platform are then compared, utilizing the automated allele concordance analysis system. Any differences in the STR allele calls between the two systems are flagged in a discordance report for further review by a qualified DNA data analyst. The automated allele concordance analysis system guides the DNA data analyst to the discordant data generated by either analysis platform. Additionally, the analyst is also directed to data that are of less than pristine quality which may have an increased potential for errors in interpretation by either analysis platform or by a human DNA data analyst. Implementation of an automated allele concordance analysis system will yield high-quality data for CODIS and free the human DNA data analyst to perform other critical duties within the laboratory.  相似文献   
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