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791.
Bram Bekaert Monique Coomans Katleen Knaepen Lucie Larno Nathalie Thijs Elisabeth Vanhoutte Wim Van de Voorde Ronny Decorte 《Forensic Science International: Genetics Supplement Series》2009,2(1):119-120
As part of the normal procedure in a forensic DNA laboratory, a quality control step of the amplified DNA is often implemented to ensure the correct amplification of the sample before it is analysed in downstream applications. A validation study was undertaken to investigate a new microchip electrophoresis system (MultiNa, Shimadzu Corporation) claiming high resolution and sensitivity compared to routine polyacrylamide gel electrophoresis (PAGE). An array of STR multiplexes (AmpFISTR™ SGM+, GenePrint® FFFL, PowerPlex™ 16, PowerPlex™ Y, an in-house Y-STR multiplex and AmpFISTR™ Profiler) was tested under both standard and low copy number PCR parameters to evaluate the accuracy, reproducibility and sensitivity of this technique. These tests showed that the microchip system did not have improved sensitivity compared to PAGE though had increased resolution and high reproducibility between samples. 相似文献
792.
Manon Jacobs Lynn Janssen Nancy Vanderheyden Bram Bekaert Wim Van de Voorde Ronny Decorte 《Forensic Science International: Genetics Supplement Series》2009,2(1):57-59
Three multiplex PCRs were developed for the analysis of 14 single-copy and 4 multi-copy Y chromosome Short Tandem Repeat (STR) loci routinely used by several public genealogical databases. These assays were used in addition to PowerPlex® Y for the analysis of 245 DNA samples from a genealogical project. In total 244 different haplotypes composed of 37–40 alleles were identified with one haplotype identical between two males with the same surname. The multi-copy loci DYS464 and DYS724 were the most polymorphic with a gene diversity of at least 0.964. The use of DYS454 and DYS455 can be questioned as these loci had the lowest gene diversity (0.039 and 0.269, respectively). 相似文献
793.
Erwin J. A. T. Mattijssen M.Sc. Wim Kerkhoff Marlies E. Bestebreurtje B.Sc. 《Journal of forensic sciences》2018,63(5):1374-1382
When reconstructing a bullet's trajectory prior to impact using the spatial orientation between two consecutive bullet defects (e.g., by probing), it is important to take the bullet's deflection into account. The (critical) ricochet angles as well as the vertical and horizontal deflection angles of eight cartridge types on laminated particle board have been studied. For all eight of the cartridge types combined, the critical ricochet angles lie between approximately 14° and 26°, while for the subgroup of the jacketed bullets, this range lies lower, between approximately 14° and 18°. The data from this study can be used to assess the accuracy and precision of the applied method. The results show that the highest deflection angles are seen near the critical ricochet angle. Generally speaking, vertical and horizontal deflection angles can almost be neglected above angles of incidence of 30° or 40° for handgun ammunition when shooting at laminated particle board. 相似文献
794.
Alexis Carpinteri Brandy Bang Kristin Klimley Ryan A. Black Vincent B. Van Hasselt 《Journal of Police and Criminal Psychology》2018,33(2):150-157
The commercial sexual exploitation of children (CSEC), specifically child trafficking, producers or consumers of child sex trafficking (i.e., prostitution), sexual abuse images, and enticement, has become a growing area of concern. The increasing profitability of CSEC, combined with the clandestine nature of the offenses, calls for immediate attention from international law enforcement and the mental health community. Paramount to the resolution of this global crisis is the identification of the perpetrators of various CSEC crimes. The research pertaining to these offenders is most frequently aggregated and limited to basic demographic data, providing a larger, more generalized picture of CSEC. The purpose of this study is to determine characteristics, within a sample of known CSEC offenders, that differentiate among offenders who engage in sex trafficking as trafficker; engage in sex trafficking as a producer or consumer; produce, distribute, or possess child sexual abuse images; and travel or use enticements to engage in illicit sexual contact with a minor. This observational, survey design includes a record review of 98 offenders who were processed through the FBI Miami Field Office. Results showed that males are more likely to engage in CSEC offenses compared to females. Offenders who collect child sexual abuse images tended to be employed, had no history of prior arrests, and were older than other CSEC offenders. Additionally, engaging in befriending strategies in order to gain access to a victim was also predictive of involvement in child sexual abuse images. Unemployment was the only statistically significant predictor of engaging in child sex trafficking as either a sex buyer or a producer. Finally, perpetrators who engaged in the traveling/enticement of victims were found to be younger, unemployed, single, and without a known history of contact offending. Implications of the findings are discussed. 相似文献
795.
Ellen Van Damme 《Trends in Organized Crime》2018,21(4):343-369
The phenomenon of gangs in El Salvador and the Democratic Republic of Congo (DRC) has already been researched, but a comparative study of gangs and gang policies is lacking. In this paper we discuss several gang violence prevention initiatives regarding the Mara Salvatrucha and Barrio 18 in El Salvador, and the kuluna and bashege in Kinshasa, DRC. In order to analyze the different gang interventions, we implement the typology of first and second gang violence prevention initiatives (Rodgers et al. 2009), and propose the evolution towards a third generation of gang violence prevention interventions. While first generation initiatives are security and law-enforcement driven, and second generation initiatives socio-preventive driven, third generation initiatives are more politically driven. The latter indicates a shift towards a vision of dialogue and negotiations to deal with gang violence. However, the different generations are not predefined within time and third generation initiatives can also be followed up by first generation initiatives, which was for example the case in the gang truce in El Salvador. Also, comparative gang research includes challenges, especially when the gang phenomenon in one country is better researched and documented than in other countries. As such, we were unable to identify politically-driven initiatives in the DRC to compare with the ones in El Salvador. Further research is thus required. With this paper we not only aim to contribute to the literature on gang violence prevention and reduction initiatives, we also want to push researchers, practitioners and policymakers to look beyond the borders when setting up gang (violence) prevention and rehabilitation projects, and to learn from other regions where similar initiatives have been implemented to deal with comparable issues of gang violence. 相似文献
796.
Swanson JW Van Dorn RA Swartz MS Smith A Elbogen EB Monahan J 《Law and human behavior》2008,32(3):228-240
Violence in schizophrenia patients may result from many factors besides the symptoms of schizophrenia. This study examined the relationship between childhood antisocial behavior and adult violence using data from the NIMH CATIE study. The prevalence of violence was higher among patients with a history of childhood conduct problems than among those without this history (28.2% vs. 14.6%; P < 0.001). In the conduct-problems group, violence was associated with current substance use at levels below diagnostic criteria. Positive psychotic symptoms were linked to violence only in the group without conduct problems. Findings suggest that violence among adults with schizophrenia may follow at least two distinct pathways-one associated with premorbid conditions, including antisocial conduct, and another associated with the acute psychopathology of schizophrenia. 相似文献
797.
Deliberate self-harm patients who leave the acute hospital environment before the completion of psychiatric assessment have an increased risk of subsequent self-harm. We considered the available data on 50 premature self-discharges identified prospectively in a general hospital with a well-developed integrated-care pathway for self-harm patients, and compared them to a control group. The self-discharge group was found to be more likely to have attempted self-poisoning without alcohol intoxication or other forms or combinations of self-harm, and an absence of identifiable previous self-harm or prior contact with local specialist psychiatric services. The two groups showed no difference in age, sex, or area of residence based on community mental health team sectors. It is proposed that these findings indicate hypotheses for further studies of why people leave the hospital without adequate assessment, and how service design could be improved in order to help them. 相似文献
798.
Despite increased interest in child abuse and neglect in the past decade, little research attention has been focused on maltreatment in handicapped populations. This is surprising given that many handicapped children display characteristics (e.g., chronic and pervasive behavioral disturbances, decreased social initiations with caregivers) that are associated with high risk for assault and neglect in nonhandicapped children. Numerous investigations have found an overrepresentation of handicapped children in maltreated samples, and results of more recent efforts reveal a high incidence of abuse and neglect in handicapped populations. Although these data underscore the high risk for maltreatment in handicapped children, a number of important issues warrant further empirical examination. Moreover, generalizations and interpretations of findings from previous research have been obfuscated by methodological shortcomings. The present paper reviews the literature concerning abuse and neglect of handicapped children. Research strategies and issues are delineated and current problems in this field are discussed. Suggestions for directions future research might take are offered. 相似文献
799.
The simultaneous determination of buprenorphine (Temgesic) and its major metabolite, N-desalkylbuprenorphine, in urine samples has been studied. By using reversed-phase high-performance liquid chromatography (HPLC) with electrochemical detection, therapeutic concentrations of unconjugated buprenorphine down to 0.2 ng/mL, and 0.15 ng/mL for the metabolite, can be detected in urine samples. This method has been applied to a variety of urine samples from drug users. The possible analytical interference from several other regulated drugs has been studied. The results were also compared with those obtained from a commercial radioimmunoassay (RIA) test. This test is only capable of detecting buprenorphine concentrations higher than 1 ng/mL. 相似文献
800.
A new convention of ‘self-help housing’ has become established over the past 20 years. However, a close examination of the literature shows that this approach is not widely implemented, but remains largely at the level of showcase projects; moreover the lowest income groups are usually not the principal beneficiaries of sites-and-service schemes. The literature gives evidence of powerful political, administrative and economic interests against the large-scale legal delivery of sites-and-services, and in favour of the continued dependence of the poor on illegal access. 相似文献