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51.
Gel ink pens have become a common writing instrument in the United States. Questioned document examiners often attempt to optically differentiate gel inks from each other and from other non-ballpoint ink writings (e.g., those from roller-ball pens). Since early formulations were primarily pigment-based, they do not elute when analyzed by thin-layer chromatography. However, recent gel ink formulations (i.e., within the past five years) include dye-based inks that can be easily separated. This study differentiates black gel inks using optical and chemical techniques. The techniques include: microscopy, visible and near infrared reflectance, near infrared luminescence, thin-layer chromatography (TLC), spot tests, and gas chromatography/mass spectrometry (GC/MS). As a result of this study a flow chart has been developed allowing for a systematic determination of a questioned ink. In addition, an analysis of volatile compounds found in gel inks revealed that there are some unique ingredients that may be found in gel inks that are not typically found in other non-ballpoint inks. 相似文献
52.
Nine STRs loci have been typed in a sample from Córdoba (Argentina). 相似文献
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Paredes M Galindo A Bernal M Avila S Andrade D Vergara C Rincón M Romero RE Navarrete M Cárdenas M Ortega J Suarez D Cifuentes A Salas A Carracedo A 《Forensic science international》2003,137(1):67-73
Genotype polymorphism studies at the 13 loci STRs included in the combined DNA index system [CODIS and PCR-based short tandem repeat loci, in: Proceedings of the Second European Symposium on Human Identification, Promega Corporation, Madison, WI, 1998, pp. 73-88; J. Forensic Sci. 46 (2001) 453] (CODIS: D3S1358, HUMvWA31, HUMFGA, D8S1179 D21S11, D18S51, D5S818, D13S317, D7S820, HUMTH01, HUMTPOX, HUMCSF1PO and D16S539) were carried out in a sample of 1429 unrelated Colombian individuals belonging to 25 different departments. As many other countries in Latino-America, Colombia shows an important admixture component, basically integrated by Amerindians, European-descendants and African-descendants. Due to the fact that only partial population analyses have been carried out in the country, the main aim of the present analysis is to establish a database of forensic interest based on the widely used CODIS systems covering the main Colombian regions. 相似文献
54.
Fondevila M Jaime JC Salas A Lareu MV Carracedo A 《Forensic science international》2003,137(2-3):217-220
Eight Y-chromosome STRs were investigated in a male population sample from Córdoba region (Argentina). Complete Y-chromosomal STRs haplotypes were obtained in 100 individuals, among which 91 different haplotypes were observed. The most common haplotype was shared by 4% of the sample, while 86 haplotypes were unique. The gene diversity was 0.9875 and the discrimination capacity was 0.8600. The combined polymorphism provides a powerful discrimination tool for routine forensic applications. 相似文献
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A case of fatal cranial injuries caused by an angle grinder is reported. The scalp lesions were typical of those produced by a cutting disk in a side-slipping movement. On the cranial vault were two bony losses of substance, one of which was deep enough for intracranial penetration of the disk. Signs of deflection of the disk, identical to those found on the scalp, were observed on the external bony table. Because of the circumstances in which the victim was discovered, in particular the damage to the machine which had a broken handle, and the lack of any indication of homicide or suicide, an accident is the most likely hypothesis. 相似文献
58.
The plural legal system in post-conflict Liberia expresses tensions between modern and customary institutions. This article seeks to understand how Liberians navigate choices in the plural legal system to address gender-based violence cases. By asking how and why people make the choices they do, we highlight how Liberians solve tensions between institutions, by creating flexible categories that allow them to pursue a course of action that does not compromise their ability to access social networks and resources. 相似文献
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Suicide is a major public health problem. Preventive measures have been sought by identifying risk factors. This study evaluates the association of childhood abuse and neglect with suicidal behavior at the time of psychiatric hospital admission. A total of 120 subjects (72 females; mean age 42.5 +/- 15.6 years old) admitted from August 2006 to July 2007 completed the Childhood Trauma Questionnaire (CTQ) to assess severity of exposure to childhood maltreatment. Thereof 62 (51.6%) patients presented with suicidal behavior at admission. Patients who had attempted suicide had significantly higher CTQ scores. Regression analysis indicated that shorter illness duration and severity of childhood maltreatment were predictors of suicidal behavior at admission. The study showed that inpatients of a psychiatric unit of a general hospital who experienced severe childhood abuse or neglect were significantly more likely to present with suicidal behavior. History of childhood maltreatment should be evaluated as an associated risk factor of suicidal behavior at admission of psychiatric inpatients. 相似文献