941 resultados para Human identification


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The knowledge of Forensic Anthropology is very importance in cases of identification of human remains. One phase of this process is the study of human height, which can be accomplished with relative ease when intact corpses, complete skeletons or long bones are available. However, the experience of Forensic Dentistry is essential in situations in which there is only information of the skull or of the teeth. The objective of this study was to review in the literature and evaluate works concerning the estimate of the height calculated from dental dimensions. Carrea, in 1920, proposed the estimation of the probable height of an individual by developing formulas for maximum and minimum heights from measurements of the lower central and lateral incisors and canines. The method was used in the case "Josef Mengele", to complement estimates. Tested in the Brazilian population, 70% of match between the actual and the estimated stature were obtained. Using more precise instruments, in the modified method, 96% of correct matching were verified. Recently, a new formula was introduced to estimate height, from measurements of upper teeth, because the technique cannot be used when jaw is not available. The correlation between height and dental dimensions is demonstrated. However, there is still a lack in scientific literature in this field, and further studies are necessary. The estimate of height from dental dimensions can be very useful and important, especially in situations where the complete skeleton it not found, and long bones are not available.

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The clinical records correspond to a set of documents where all information of the patient is stored. When properly confectioned and filed by the dentist, it may serve as a tool for success in dental expertise. The aim of this paper is to present the importance of proper confection of dental records in human identification by means the presentation of a case of identification, occurred in a São Paulo state city. The notes present in the dental records of the alleged victim were very poor, even with a contradiction. However, having endodontic treatment been performed, the comparative analysis between the radiographs of the skull of the victim (postmortem) and the endodontic treatment of tooth 22 (antemortem) permitted to observe total coincidence between the details of such treatment, and anatomical features present in other dental elements. These important parameters of comparison indicated that the body was of the suspect and, due to the number of coincidences, it could not belong to another individual. Nevertheless, the clinical documentation provided was deficient, and presented contradictory data. Because of its fundamental importance for human identification, it is essential that dental professionals take the necessary care to ensure its proper confection and custody, seeking to make the clinical records also an efficient instrument of consultation in identification cases.

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Objective: The aim of this research was to determine the knowledge level of 400 dentists registered in the Regional Dental Council of Cuiabá, through a questionnaire about the importance of records in the process of human identification. Results: We observed that 48.36% of them dispense between 10 and 20 minutes. Only 13.1% of the surveyed dentists did not have the habit of writing down the oral conditions of their patients before starting treatment and 42.62% have only one odontogram filled. From the 122 participants, 11.11% reported that the documentation had no utility to establish the patients identity. To make the situation worse, 33.6% of them said they did not keep the records of patients updated. Conclusion: We conclude that the dentist of Cuiabá has enough knowledge on preparing, maintaining and importance of dental records before the death in the identification process for establishing the patient identity. But, always he did not properly fills the dental records, thus it has been reducing their clinical, administrative and legal value.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Facial reconstruction is a method that seeks to recreate a person's facial appearance from his/her skull. This technique can be the last resource used in a forensic investigation, when identification techniques such as DNA analysis, dental records, fingerprints and radiographic comparison cannot be used to identify a body or skeletal remains. To perform facial reconstruction, the data of facial soft tissue thickness are necessary. Scientific literature has described differences in the thickness of facial soft tissue between ethnic groups. There are different databases of soft tissue thickness published in the scientific literature. There are no literature records of facial reconstruction works carried out with data of soft tissues obtained from samples of Brazilian subjects. There are also no reports of digital forensic facial reconstruction performed in Brazil. There are two databases of soft tissue thickness published for the Brazilian population: one obtained from measurements performed in fresh cadavers (fresh cadavers' pattern), and another from measurements using magnetic resonance imaging (Magnetic Resonance pattern). This study aims to perform three different characterized digital forensic facial reconstructions (with hair, eyelashes and eyebrows) of a Brazilian subject (based on an international pattern and two Brazilian patterns for soft facial tissue thickness), and evaluate the digital forensic facial reconstructions comparing them to photos of the individual and other nine subjects. The DICOM data of the Computed Tomography (CT) donated by a volunteer were converted into stereolitography (STL) files and used for the creation of the digital facial reconstructions. Once the three reconstructions were performed, they were compared to photographs of the subject who had the face reconstructed and nine other subjects. Thirty examiners participated in this recognition process. The target subject was recognized by 26.67% of the examiners in the reconstruction performed with the Brazilian Magnetic Resonance Pattern, 23.33% in the reconstruction performed with the Brazilian Fresh Cadavers Pattern and 20.00% in the reconstruction performed with the International Pattern, in which the target-subject was the most recognized subject in the first two patterns. The rate of correct recognitions of the target subject indicate that the digital forensic facial reconstruction, conducted with parameters used in this study, may be a useful tool. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

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Human identification from a skull is a critical process in legal and forensic medicine, specially when no other means are available. Traditional clay-based methods attempt to generate the human face, in order to identify the corresponding person. However, these reconstructions lack of objectivity and consistence, since they depend on the practitioner. Current computerized techniques are based on facial models, which introduce undesired facial features when the final reconstruction is built. This paper presents an objective 3D craniofacial reconstruction technique, implemented in a graphic application, without using any facial template. The only information required by the software tool is the 3D image of the target skull and three parameters: age, gender and Body Mass Index (BMI) of the individual. Complexity is minimized, since the application database only consists of the anthropological information provided by soft tissue depth values in a set of points of the skull.

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This paper presents a hand biometric system for contact-less, platform-free scenarios, proposing innovative methods in feature extraction, template creation and template matching. The evaluation of the proposed method considers both the use of three contact-less publicly available hand databases, and the comparison of the performance to two competitive pattern recognition techniques existing in literature: namely Support Vector Machines (SVM) and k-Nearest Neighbour (k-NN). Results highlight the fact that the proposed method outcomes existing approaches in literature in terms of computational cost, accuracy in human identification, number of extracted features and number of samples for template creation. The proposed method is a suitable solution for human identification in contact-less scenarios based on hand biometrics, providing a feasible solution to devices with limited hardware requirements like mobile devices

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Entre as muitas aplicações das tecnologias de identificação biológica humana, estão as finalidades forenses. O objetivo desta pesquisa foi verificar frequências alélicas de Short Tandem Repeat (STR) e os parâmetros estatísticos de interesse em genética de populações e forense para desenvolver o primeiro banco de dados populacional de DNA na Faculdade de Odontologia de Bauru, Universidade de São Paulo, (FOB/USP) para futuros usos forenses. Frequências alélicas de 15 locos autossômicos e do marcador de gênero amelogenina foram determinadas utilizando amostras de 200 μL de saliva doados por 296 alunos de graduação da FOB/USP, com idade ≥ 18 anos, após aprovação ética. Os testes laboratoriais foram feitos com kits comerciais. Resultados e parâmetros estatísticos foram obtidos por meio de programas clássicos: GeneMapper-ID-X, MS Excel 2002 versão 10.6871.6870, GenAlEx 6.5 e Arlequin 3.5, comparando quatro populações (brasileira, portuguesa, norte-americana e a população deste estudo). Os locos mais polimórficos foram D18S51 (17 alelos) e FGA (15 alelos), seguidos pelo D21S11 (13 alelos) e os menos polimórficos foram D16S539 e TH01 (7 alelos cada). A análise comparativa com amostra da população brasileira proveniente de estudos anteriores (n > 100.000) pelo teste goodness of fit X2 index não mostrou diferenças significativas entre estes grupos (p = 0,9999). Outros parâmetros estatísticos foram calculados comparando as populações: local (deste estudo), portuguesa e norte-americana. A análise de variância molecular (AMOVA) entre as três populações, entre as pessoas da mesma população e para cada pessoa de cada população mostrou que existe uma elevada variância individual (99%), que esta variância é mantida uniformemente entre as pessoas da mesma amostra/região (1%) e entre as três populações estudadas (0%). O estudo confirmou o elevado grau de polimorfismo e a alta heterozigosidade (96,5%) da população. Houve diferença significativa quanto ao gênero (79,7% mulheres) quando comparado à população brasileira em geral (50,4%), explicada pelas características do corpo discente da FOB/USP composto por 80,6% de pessoas do gênero feminino. Interessante foi a observação de uma microvariante alélica no loco D18S51, fora da escada padrão e da escala de abrangência do kit, correspondente ao alelo 29, ainda não definida na base de dados internacional (STRBase, atualizada em 07/08/2015). Esta microvariante deverá ser confirmada por testes familiares e sequenciamento de DNA para verificar a possibilidade de outra ocorrência familiar ou duplicação de nucleotídeos. No futuro, os dados obtidos neste estudo devem ser incorporados ao banco de dados da população brasileira e podem ser considerados como referência genética da população regional, ajudando a elucidar casos forenses. Após a confirmação, a potencial nova microvariante alélica contribuirá para a base de dados internacional STRBase.

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This dissertation develops an image processing framework with unique feature extraction and similarity measurements for human face recognition in the thermal mid-wave infrared portion of the electromagnetic spectrum. The goals of this research is to design specialized algorithms that would extract facial vasculature information, create a thermal facial signature and identify the individual. The objective is to use such findings in support of a biometrics system for human identification with a high degree of accuracy and a high degree of reliability. This last assertion is due to the minimal to no risk for potential alteration of the intrinsic physiological characteristics seen through thermal infrared imaging. The proposed thermal facial signature recognition is fully integrated and consolidates the main and critical steps of feature extraction, registration, matching through similarity measures, and validation through testing our algorithm on a database, referred to as C-X1, provided by the Computer Vision Research Laboratory at the University of Notre Dame. Feature extraction was accomplished by first registering the infrared images to a reference image using the functional MRI of the Brain’s (FMRIB’s) Linear Image Registration Tool (FLIRT) modified to suit thermal infrared images. This was followed by segmentation of the facial region using an advanced localized contouring algorithm applied on anisotropically diffused thermal images. Thermal feature extraction from facial images was attained by performing morphological operations such as opening and top-hat segmentation to yield thermal signatures for each subject. Four thermal images taken over a period of six months were used to generate thermal signatures and a thermal template for each subject, the thermal template contains only the most prevalent and consistent features. Finally a similarity measure technique was used to match signatures to templates and the Principal Component Analysis (PCA) was used to validate the results of the matching process. Thirteen subjects were used for testing the developed technique on an in-house thermal imaging system. The matching using an Euclidean-based similarity measure showed 88% accuracy in the case of skeletonized signatures and templates, we obtained 90% accuracy for anisotropically diffused signatures and templates. We also employed the Manhattan-based similarity measure and obtained an accuracy of 90.39% for skeletonized and diffused templates and signatures. It was found that an average 18.9% improvement in the similarity measure was obtained when using diffused templates. The Euclidean- and Manhattan-based similarity measure was also applied to skeletonized signatures and templates of 25 subjects in the C-X1 database. The highly accurate results obtained in the matching process along with the generalized design process clearly demonstrate the ability of the thermal infrared system to be used on other thermal imaging based systems and related databases. A novel user-initialization registration of thermal facial images has been successfully implemented. Furthermore, the novel approach at developing a thermal signature template using four images taken at various times ensured that unforeseen changes in the vasculature did not affect the biometric matching process as it relied on consistent thermal features.

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Com o presente trabalho pretende-se discutir a importância do DNA na resolução de casos de investigação forense. O Homem, desde os tempos mais remotos tem revelado interesse na confirmação da identidade dos seus semelhantes, pelo desenvolvimento e prática de diversas técnicas de identificação. A partir de uma revisão da literatura, fez-se o estudo dos métodos de identificação humana, sendo este mais aprofundado no que diz respeito ao DNA. Frequentemente são encontrados corpos em que a única peça disponível para o processo de identificação é o dente. As peças dentárias são as estruturas mais resistentes e estáveis do corpo humano, mantendo as suas características e propriedades por longos períodos de tempo pós-morte. A análise do DNA contribui de forma muito importante para os processos de reconhecimento humano, principalmente em casos em que outros métodos de identificação falham devido a decomposição, fragmentação, incineração ou inexistência de dados comparativos ante-morte. Para a obtenção de um perfil genético é necessário executar as seguintes etapas: extração do DNA, sua quantificação e amplificação seguida de análise de determinadas regiões do genoma. Nos dias de hoje, muitos casos de identificação necessitam de uma abordagem multidisciplinar, isto porque em algumas situações existe falta de material padrão ou, por outro lado, pode haver mais do que uma evidência a ser examinada.

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A security system based on the recognition of the iris of human eyes using the wavelet transform is presented. The zero-crossings of the wavelet transform are used to extract the unique features obtained from the grey-level profiles of the iris. The recognition process is performed in two stages. The first stage consists of building a one-dimensional representation of the grey-level profiles of the iris, followed by obtaining the wavelet transform zerocrossings of the resulting representation. The second stage is the matching procedure for iris recognition. The proposed approach uses only a few selected intermediate resolution levels for matching, thus making it computationally efficient as well as less sensitive to noise and quantisation errors. A normalisation process is implemented to compensate for size variations due to the possible changes in the camera-to-face distance. The technique has been tested on real images in both noise-free and noisy conditions. The technique is being investigated for real-time implementation, as a stand-alone system, for access control to high-security areas.

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Previous studies have shown that the human lens contains glycerophospholipids with ether linkages. These lipids differ from conventional glycerophospholipids in that the sn-1 substituent is attached to the glycerol backbone via an 1-O-alkyl or an 1-O-alk-1'-enyl ether rather than an ester bond. The present investigation employed a combination of collision-induced dissociation (CID) and ozone-induced dissociation (OzID) to unambiguously distinguish such 1-O-alkyl and 1-O-alk-1'-enyl ethers. Using these methodologies the human lens was found to contain several abundant 1-O-alkyl glycerophos-phoethanolamines, including GPEtn(16:0e/9Z-18:1), GPEtn(11Z-18:1e/9Z-18:1), and GPEtn(18:0e/9Z-18:1), as well as a related series of unusual 1-O-alkyl glycerophosphoserines, including GPSer(16:0e/9Z-18:1), GPSer(11Z-18:1e/9Z-18:1), GPSer(18:0e/9Z-18:1) that to our knowledge have not previously been observed in human tissue. Isomeric 1-O-alk-1'-enyl ethers were absent or in low abundance. Examination of the double bond position within the phospholipids using OzID revealed that several positional isomers were present, including sites of unsaturation at the n-9, n-7, and even n-5 positions. Tandem CID/OzID experiments revealed a preference for double bonds in the n-7 position of 1-O-ether linked chains, while n-9 double bonds predominated in the ester-linked fatty acids [e.g., GPEtn(11Z-18:1e/9Z-18:1) and GPSer(11Z-18:1e/9Z-18:1)]. Different combinations of these double bond positional isomers within chains at the sn-1 and sn-2 positions point to a remarkable molecular diversity of ether-lipids within the human lens.