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311.
Evaluation of laser desorption mass spectrometry and UV accelerated aging of dyes on paper as tools for the evaluation of a questioned document 总被引:1,自引:0,他引:1
Laser desorption mass spectrometry (LDMS) may be used for the detection and identification of dyes found in inks. Naturally-aged and artificially-aged blue and black ballpoint pen inks containing the cationic dye methyl violet were analyzed on paper. The average molecular weight of the dye sample was calculated from LD mass spectral data and plotted versus time. The resulting aging curves demonstrate that, as dye degradation increases, the average molecular weight of the dye decreases. Typical variables involved in ink aging, such as the type of paper and ink formulation, were investigated. Results show that these variables influence the rate of dye degradation. Furthermore, UV accelerated aging has been developed and tested as an alternative to thermal approaches. 相似文献
312.
A study of 30 cases of violence from a total sample of 199 cases of infant abductions between the years 1983 and 2000 included a subsample of six (or 20%) where the kidnapping was by cesarean section. The six cases are classified by type of crime. Four cases were classified as personal cause homicide, subtype cesarean section homicide; one case classified as personal cause, subtype domestic homicide, and one case classified as a criminal enterprise homicide. The behavioral profiles of the abductors included a confidence style approach to the victim mother, deception, and planning of the cesarean section. The forensic psychodynamics suggest a dual motive to cement a failing partner relationship and to fulfill a childbearing and delivery fantasy. Cesarean section murder suggests a new category of personal cause homicide. 相似文献
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Byard RW James RA Gilbert JD 《The American journal of forensic medicine and pathology》2002,23(3):238-244
Analysis of a series of deaths between 1986 and 2001 resulting from natural disease, accidents, suicides, and homicide, where postmortem animal activity had traumatized bodies, was undertaken at the Forensic Science Center in Adelaide to demonstrate the range of lesions that may occur and problems in interpretation that result. Tissue damage had been caused by a variety of animals, including fly larvae, ants, birds, dogs, rodents, sea lice, and sharks. Postmortem animal activity had disguised injuries, modified wounds, and created the appearances of inflicted injury. Problems with identification occurred after postmortem facial trauma, and loss of organ parenchyma had interfered with, or precluded, the precise determination of the manner of death in some cases. Specific kinds of tissue and organ damage may occur after death, necessitating careful assessment of lesions in a search for characteristic features of animal activity. The pattern of lesions may enable identification of the particular species of animal involved. 相似文献
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Intramyocardial small vessel abnormalities are not commonly recognized. The best known abnormality is fibromuscular dysplasia involving the sinoatrial or atrioventricular nodal arteries. Small vessel disease has been reported as an isolated cardiac anomaly in individuals with sudden death, and may also be associated with other cardiac conditions including hypertrophic cardiomyopathy and mitral valve prolapse. The nature of the association is unknown, and the mechanism causing sudden death is sometimes obscure. We describe pathological changes of the intramyocardial small vessels of three individuals with sudden death. Abnormalities involved small vessels at different levels. In all the cases, the abnormalities were thought to have caused or contributed to the individual's death. The possible mechanisms of this are discussed. 相似文献
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Roslyn M. Caldwell Richard P. Wiebe H. Harrington Cleveland 《Journal of youth and adolescence》2006,35(4):587-598
This study examined the ability of future certainty—an individual's perception of future stability, operationalized as the likelihood of certain life outcomes–to explain variance in delinquency and school adjustment, while controlling for economic, neighborhood, and family factors, among a cross-sectional sample of 1422 male and 1562 female African American adolescents drawn from the National Longitudinal Study of Adolescent Health (Add Health). Three kinds of future certainty were examined: future life certainty (e.g., life expectancy), marriage certainty, and college certainty. In hierarchical multiple regression analyses, future certainty and family functioning were stronger predictors than economic and neighborhood variables: neighborhood disorganization and family socioeconomic status. Future life certainty and expectations of attending college were stronger predictors of delinquency among males than females. Marriage certainty was the weakest predictor of the three certainty variables. 相似文献