25 resultados para Digital Forensics, Forensic Computing, Forensic Science
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)
Resumo:
Mitochondrial DNA (mtDNA) population data for forensic purposes are still scarce for some populations, which may limit the evaluation of forensic evidence especially when the rarity of a haplotype needs to be determined in a database search. In order to improve the collection of mtDNA lineages from the Iberian and South American subcontinents, we here report the results of a collaborative study involving nine laboratories from the Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) and EMPOP. The individual laboratories contributed population data that were generated throughout the past 10 years, but in the majority of cases have not been made available to the scientific community. A total of 1019 haplotypes from Iberia (Basque Country, 2 general Spanish populations, 2 North and 1 Central Portugal populations), and Latin America (3 populations from Sao Paulo) were collected, reviewed and harmonized according to defined EMPOP criteria. The majority of data ambiguities that were found during the reviewing process (41 in total) were transcription errors confirming that the documentation process is still the most error-prone stage in reporting mtDNA population data, especially when performed manually. This GHEP-EMPOP collaboration has significantly improved the quality of the individual mtDNA datasets and adds mtDNA population data as valuable resource to the EMPOP database (www.empop.org). (C) 2010 Elsevier Ireland Ltd. All rights reserved.
Resumo:
Introduction: Recently developed portable dental X-ray units increase the mobility of the forensic odontologists and allow more efficient X-ray work in a disaster field, especially when used in combination with digital sensors. This type of machines might also have potential for application in remote areas, military and humanitarian missions, dental care of patients with mobility limitation, as well as imaging in operating rooms. Objective: To evaluate radiographic image quality acquired by three portable X-ray devices in combination with four image receptors and to evaluate their medical physics parameters. Materials and methods: Images of five samples consisting of four teeth and one formalin-fixed mandible were acquired by one conventional wall-mounted X-ray unit, MinRay (R) 60/70 kVp, used as a clinical standard, and three portable dental X-ray devices: AnyRay (R) 60 kVp, Nomad (R) 60 kVp and Rextar (R) 70 kVp, in combination with a phosphor image plate (PSP), a CCD, or a CMOS sensor. Three observers evaluated images for standard image quality besides forensic diagnostic quality on a 4-point rating scale. Furthermore, all machines underwent tests for occupational as well as patient dosimetry. Results: Statistical analysis showed good quality imaging for all system, with the combination of Nomad (R) and PSP yielding the best score. A significant difference in image quality between the combination of the four X-ray devices and four sensors was established (p < 0.05). For patient safety, the exposure rate was determined and exit dose rates for MinRay (R) at 60 kVp, MinRay (R) at 70 kVp, AnyRay (R), Nomad (R) and Rextar (R) were 3.4 mGy/s, 4.5 mGy/s, 13.5 mGy/s, 3.8 mGy/s and 2.6 mGy/s respectively. The kVp of the AnyRay (R) system was the most stable, with a ripple of 3.7%. Short-term variations in the tube output of all the devices were less than 10%. AnyRay (R) presented higher estimated effective dose than other machines. Occupational dosimetry showed doses at the operator`s hand being lowest with protective shielding (Nomad (R): 0.1 mu Gy). It was also low while using remote control (distance > 1 m: Rextar (R) < 0.2 mu Gy, MinRay (R) < 0.1 mu Gy). Conclusions: The present study demonstrated the feasibility of three portable X-ray systems to be used for specific indications, based on acceptable image quality and sufficient accuracy of the machines and following the standard guidelines for radiation hygiene. (C) 2010 Elsevier Ireland Ltd. All rights reserved.
Resumo:
Determining the season of death by means of the composition of the families of insects infesting carrion is rarely attempted in forensic studies and has never been statistically modelled. For this reason, a baseline-category logit model is proposed for predicting the season of death as a function of whether the area where the carcass was exposed is sunlit or shaded and of the relative abundance of particular families of carrion insects (Calliphoridae, Fanniidae, Sarcophagidae, and Formicidae). The field study was conducted using rodent carcasses (20-252 g) in an urban forest in southeastern Brazil. Four carcasses (2 in a sunlit and 2 in a shaded area) were placed simultaneously at the study site, twice during each season from August 2003 through June 2004. The feasibility of the model, measured in terms of overall accuracy, is 64 +/- 14%. It is likely the proposed model will assist forensic teams in predicting the season of death in tropical ecosystems, without the need of identifying the species of specimens or the remains of carrion insects.
Resumo:
Allele frequency distributions and population data for 12 Y-chromosomal short tandem repeats (STRs) included in the PowerPlex (R) Y Systems (Promega) were obtained for a sample of 200 healthy unrelated males living in S (a) over tildeo Paulo State (Southeast of Brazil). A total of 192 haplotypes were identified, of which 184 were unique and 8 were found in 2 individuals. The average gene diversity of the 12 Y-STR was 0.6746 and the haplotype diversity was 0.9996. Pairwise analysis confirmed that our population is more similar with the Italy, North Portugal and Spain, being more distant of the Japan. (c) 2007 Elsevier Ireland Ltd. All rights reserved.
Resumo:
Mitochondrial DNA (mtDNA) analysis has proved useful for forensic identification especially in cases where nuclear DNA is not available, such as with hair evidence. Heteroplasmy, the presence of more than one type of mtDNA in one individual, is a common situation often reported in the first and second mtDNA hypervariable regions (HV1/HV2), particularly in hair samples. However, there is no data about heteroplasmy frequency in the third mtDNA hypervariable region (HV3). To investigate possible heteroplasmy hotspots, HV3 from hair and blood samples of 100 individuals were sequenced and compared. No point heteroplasmy was observed, but length heteroplasmy was, both in C-stretch and CA repeat. To observe which CA ""alleles"" were present in each tissue, PCR products were cloned and re-sequenced. However, no variation among CA alleles was observed. Regarding forensic practice, we conclude that point heteroplasmy in HV3 is not as frequent as in the HV1/HV2.
Resumo:
In this work, a fast, non destructive voltammetric method for cocaine detection in acetonitrile medium using a platinum disk electrode chemically modified with cobalt-hexacyanoferrate (CoHCFe) film is described. The deposition of CoHCFe film at platinum disk (working electrode) was carried out in aqueous solution containing NaClO(4) at 0.1 mol L(-1) as supporting electrolite. Stability studies of the film and subsequent voltammetric analysis of cocaine were made in acetonitrile medium with NaClO4 at 0.1 mol L(-1) as supporting electrolite. A reversible interaction between cocaine and CoHCFe at the film produces a proportional decrease of original peak current, due to the formation of a complex between cocaine and cobalt ions, with subsequent partial passivation of the film surface, being the intensity of current decrease used as analytical signal for cocaine. A linear dependence of cocaine detection was carried out in the range from 2.4 x 10 x 4 to 1.5 x 10(-3) mol L(-1), with a linear correlation coefficient of 0.994 and a detection limit of 1.4 x 10 x 4 mol L(-1). The analysis of confiscated samples by the proposed method indicated cocaine levels from 37% to 95% (m/m) and these results were validated by comparison to HPLC technique, being obtained good correlation between both methods. (C) 2009 Elsevier Ireland Ltd. All rights reserved.
Resumo:
Scanning electronmicroscopy (SEM) has been used in forensic science in many ways. The reports of cases in which SEM has been used as an auxiliary method in the investigation of exhumed bones are rare. In this article, we report an exhumation that was made to determine if a seized weapon could have been used in a homicide. We used SEM to analyze a fracture in the interior of the skull of the victim. The findings described in this article showed us that it is possible to develop new researches in this field. (C) 2010 Elsevier Ireland Ltd. All rights reserved.
Resumo:
Purpose: To evaluate the role of alcohol and drug consumption between sexual offenders against boys and girls. Method: It was an observational, retrospective and cross-sectional study carried out by the Ambulatory for the treatment of sexual disorders of ABC Medical College, Santo Andre, Sao Paulo, Brazil (ABSex). The sample comprised 104 convicts, over 18 years old, sentenced only for sexual crimes against children (below 11 years old). Alcohol and drug consumption, sexual abuse history, sexual impulsivity, and risk of recidivism were evaluated. Results: The sexual offenders against boys showed higher alcohol consumption problems than sexual offenders against girls (chi(2) = 19.76, 1 d.f., p < 0.01). The severity of alcohol consumption was also significantly higher in the sexual offenders against non-related boys than in the sexual offenders against non-related girls (p = 0.037, ANOVA). After adjustment for other variables, such as monthly income before the penalty and alcohol consumption at the moment of the crime, the alcohol consumption severity in sexual offenders against boys was significantly higher than in sexual offenders against girls (OR = 1.05, CI 1.01-1.08, p < 0.01). Conclusions: Alcohol use or abuse is associated with the perpetration of sexual aggression. The role of alcohol consumption seems to be greater in sexual offenders against boys than in girls and this can contribute to criminal recidivism. (C) 2007 Elsevier Ireland Ltd. All rights reserved.
Resumo:
In immediate fire deaths, pulmonary injury may be the main source of mortality, being important to document the histologic findings for the purpose of excluding other modes of death, such as from asphyxia with no gross findings. In this context, a group of morphologic determinants have been targeted with useful makers of pulmonary injury. To facilitate the determination of whether an individual was deceased before the start of a fire and validate the importance of parenchymal alterations in pulmonary injury in fire deaths, we studied lungs in victims of fire (N = 28) and suffocation (N = 40), creating a mathematical model using cluster analysis. For this purpose, a semiquantitative analysis of the distal parenchyma was performed to evaluate the amount of bronchiolar dilatation, overinsufflation (ductal and alveolar), collapse (ductal and alveolar), passive congestion, alveolar edema, and hemorrhage (interstitial and alveolar). These 7 histologic determinants were useful to discriminate fire (bronchiolar dilatation, ductal overinsuflation, alveolar overinsuflation, alveolar hemorrhage) from suffocation lung injuries (alveolar collapse, congestion, and edema). We conclude that these determinants should be included in the routine of forensic pathology.
Resumo:
Personality disorders are associated with criminality and antisocial and borderline personalities as strong predictors of violence. Nevertheless antisocial patients show more instrumental violence, while borderline patients more emotional violence. We surveilled medical records of a personality disorder facility, searching data of aggression and crimes against property among 11 patients with antisocial personality disorder and 19 borderline personality disorder. We found that there are differences regarding engagement in violence and lawbreaking according to the personality disorder: antisocial patients statistically engage more in crimes against property than the borderline patients, and more in this kind of crime than in aggression, whilst borderline patients show a tendency to engage more in episodes of aggression and physical violence than antisocial patients, and less in crimes against property. We conclude that the distinct personality leads to a distinct pattern of crimes and violence: antisocial patients are c old and get more involved in crimes requiring more detailed planning, whilst borderline patients are impulsive and engage in explosive episodes of physical violence. Further studies on the association among personality disorder, behavior pattern and violence type may be useful for both treatment and criminal profiling. (C) 2008 Elsevier Ireland Ltd. All rights reserved.
Resumo:
In recent years, alcohol consumption has been considered an important public health problem. Ethanol, the alcohol used in beverages, is a drug that affects the central nervous system (CNS) and impairs driving skills and co-ordination, increasing risk of deaths and injuries derived from crashes and road accidents. Consumption of alcoholic beverages is implicated with premature deaths, injuries and damages caused by motor vehicle crashes, which result in high costs to government and society. Considering that alcohol consumption is the main responsible factor for deaths and disabilities in young people, the aim of this work was to evaluate the prevalence of blood alcohol in offenders and/or fatal and non-fatal victims of traffic occurrences in the region of Ribeirao Preto, Sao Paulo State, from 2005 to 2007. The results revealed that in 2134 cases investigated, blood alcohol positivity was generally found in young adults, 25-45 years old and male. The study showed the high risk of drinking and driving and the importance in establishing actions of prevention and intervention to promote the reduction in the number of traffic occurrences related to consumption of alcoholic beverages. (C) 2010 Elsevier Ireland Ltd. All rights reserved.
Resumo:
PURPOSE: This study evaluated the quality of DNA obtained from stored human saliva and its applicability to human identification. METHODS: The saliva samples of 20 subjects, collected in the form of saliva in natura and from mouth swabs and stored at -20ºC, were analyzed. After 7 days, the DNA was extracted from the 40 saliva samples and subjected to PCR and electrophoresis. After 180 days, the technique was repeated with the 20 swab samples. RESULTS: The first-stage results indicated that DNA was successfully extracted in 97.5% of reactions, 95% of saliva in natura and 100% of swab saliva samples, with no statistically significant difference between the forms of saliva. In the second phase, the result was positive for all 20 analyzed samples (100%). Subsequently, in order to analyze the quality of the DNA obtained from human saliva, the SIX3-2 gene was tested on the 20 mouth swab samples, and the PCR products were digested using the MbO1 restriction enzyme to evaluate polymorphisms in the ADRA-2 gene, with positive results for most samples. CONCLUSION: It was concluded that the quantity and quality of DNA from saliva and the techniques employed are adequate for forensic analysis of DNA.
Resumo:
OBJECTIVES: This study assessed the bone density gain and its relationship with the periodontal clinical parameters in a case series of a regenerative therapy procedure. MATERIAL AND METHODS: Using a split-mouth study design, 10 pairs of infrabony defects from 15 patients were treated with a pool of bovine bone morphogenetic proteins associated with collagen membrane (test sites) or collagen membrane only (control sites). The periodontal healing was clinically and radiographically monitored for six months. Standardized pre-surgical and 6-month postoperative radiographs were digitized for digital subtraction analysis, which showed relative bone density gain in both groups of 0.034 ± 0.423 and 0.105 ± 0.423 in the test and control group, respectively (p>0.05). RESULTS: As regards the area size of bone density change, the influence of the therapy was detected in 2.5 mm² in the test group and 2 mm² in the control group (p>0.05). Additionally, no correlation was observed between the favorable clinical results and the bone density gain measured by digital subtraction radiography (p>0.05). CONCLUSIONS: The findings of this study suggest that the clinical benefit of the regenerative therapy observed did not come with significant bone density gains. Long-term evaluation may lead to a different conclusions.
Resumo:
Much has been discussed about Digital Literacy, but it is quite obscure the identification of the skills required to develop such process. This study was done towards an integration of the Digital Literacy process to the specific informational skills a person may dominate, search, retrieve and use information efficiently, in its professional, academic or personal life. The main objective of this work is to propose methodological parameters for training in informational skills. Otherwise, the specific objectives are associated to the supposition and identification of the desired skills of the Digital Literacy program participants. The methodological procedures applied to the research are of exploratory character, and to do so two tools are used: the literature research and case studies. Besides having the methodology in structured information competence, the study points out to the fact that the country is too far from what is desired concerning development and employment of Digital Literacy programs consistent enough to support the teaching and learning of searching, recovering and using of information by the participants. Therefore, it is essential to create programs that provide not only machinery, but motivate individuals to develop informational skills to help in the learning process.