755 research outputs found

    The Diary of Anne Frank (December 14-15, 1962)

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    Program for The Diary of Anne Frank (December 14-15, 1962

    A solution based on iris recognition for data protection on mobile devices

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    Orientadores: Leandro Aparecido Villas, Fabio Augusto FariaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: O uso de dispositivos móveis em atividades diárias, tais como, acessar a serviços bancários, efetuar compras on-line e trocar mensagens via e-mail ou redes sociais, tornou-se mais frequente na vida das pessoas. Assegurar a privacidade e a segurança dos dados contidos nesses dispositivos, é essencial para incentivar o surgimento de novas aplicações e aumentar a adesão de novos usuários. Para este fim, a utilização de biometria tem sido muito atraente, devido o alto grau de dissimilaridade entre as propriedades biológicas de indivíduos distintos. Em particular, a biometria por meio de íris destaca-se dentre as demais técnicas de biometria, por possuir um padrão de textura rico em detalhes que permanecem estáveis ao longo da vida, diferentemente da impressão digital e da face que estão sujeitas a grandes variações. Além disso, não há necessidade de hardware adicional, uma vez que o sensor presente na maioria dos dispositivos móveis é suficiente para capturar as imagens de íris a distância, sem haver contato direto do indivíduo com o sensor (menos intrusiva). Contudo, lidar com imagens de íris capturadas por usuários ingênuos (proprietários de dispositivos móveis) e em ambientes não controlados torna o reconhecimento de íris uma tarefa desafiadora, e por isso, requer métodos mais robustos para desempenhar essa tarefa. Este trabalho apresenta uma solução baseada em descritores binários de pontos-chave (ou keypoints) para realizar a codificação da textura de íris, onde apenas os pixels entorno dos keypoints são utilizados na codificação, por considerar que alguns pixels são mais estáveis do que outros, e desta forma, é reduzido o impacto causado pela fragilidade de bits, problema frequente em abordagens que utilizam todos os pixels para gerar a codificação. São comparados três descritores binários de keypoints bem conhecidos (BRIEF, ORB e BRISK) para identificar qual é o mais adequado para ser utilizado na codificação da textura de íris. Em comum, os três descritores são eficientes no uso de memória e no tempo de processamento, e possuem bom desempenho para aplicações de reconhecimento. Além disso, são comparados três diferentes métodos de segmentação existentes na literatura para avaliar o impacto causado no desempenho do reconhecimento. São utilizados dois conjuntos de imagens de íris amplamente conhecidos na literatura, chamados CASIA e MICHE-I, para avaliação da solução proposta. Os resultados das simulações apresentaram um bom desempenho, considerando as métricas de eficácia, uso de memória e tempo de processamentoAbstract: The use of mobile devices in daily activities, such as access to banking services, online buying, send/receive emails or interaction on social networks, has become more often on people¿s lives. To ensure the privacy and security of the data contained on these devices it is essential to encourage the emergence of new applications and increase users involvement. To this end, biometrics has been very attractive due to the high dissimilarity among biological properties of distinct individuals. In particular, iris recognition stands out among other biometric techniques. The iris presents a rich texture pattern that remains stable throughout our life. On the other hand, other biometric techniques are subject to large variations. Furthermore, no additional hardware is required, since that sensor already present in most mobile devices is sufficient to capture the iris image at distance, without any direct contact with the sensor (less intrusive). However, dealing with samples captured by naive users (owners of mobile devices) and uncontrolled settings make iris recognition a challenging task, and therefore requires more robust methods to address them. In this work we present a solution based on binary keypoint descriptors to perform iris encoding. In our solution, only surrounding pixels of keypoints are used, considering that some pixels are more stable than others, and thus, the impact caused by bit fragility is reduced, which is a frequent problem in approaches that use all the pixels to generate the coding. Three well known binary keypoint descriptors - BRIEF, ORB and BRISK - are compared to identify which is the most suitable for use on the iris encoding. In common, all of them are efficient and have good performance for recognition applications. Moreover, three different segmentation methods are compared to assess the impact on recognition performance. We used two iris datasets widely known in literature, called CASIA and MICHE-I, to assess the proposed solution. The simulation results shown a good performance considering the metrics effectiveness, memory usage and processing timeMestradoCiência da ComputaçãoMestre em Ciência da Computação4716.4Funcam

    A melanin-independent interaction between Mc1r and Met signalling pathways is required for HGF-dependent melanoma

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    Melanocortin 1 receptor (MC1R) signaling stimulates black eumelanin production through a cAMP-dependent pathway. MC1R polymorphisms can impair this process, resulting in a predominance of red phaeomelanin. The red hair, fair skin and UV sensitive phenotype is a well-described melanoma risk factor. MC1R polymorphisms also confer melanoma risk independent of pigment. We investigated the effect of Mc1r deficiency in a mouse model of UV-induced melanoma. C57BL/6-Mc1r+/+-HGF transgenic mice have a characteristic hyperpigmented black phenotype with extra-follicular dermal melanocytes located at the dermal/epidermal junction. UVB induces melanoma, independent of melanin pigmentation, but UVA-induced and spontaneous melanomas are dependent on black eumelanin. We crossed these mice with yellow C57BL/6-Mc1re/e animals which have a non-functional Mc1r and produce predominantly yellow phaeomelanin. Yellow C57BL/6-Mc1re/e-HGF mice produced no melanoma in response to UVR or spontaneously even though the HGF transgene and its receptor Met were expressed. Total melanin was less than in C57BL/6-Mc1r+/+-HGF mice, hyperpigmentation was not observed and there were few extra-follicular melanocytes. Thus, functional Mc1r was required for expression of the transgenic HGF phenotype. Heterozygous C57BL/6-Mc1re/+-HGF mice were black and hyperpigmented and, although extra-follicular melanocytes and skin melanin content were similar to C57BL/6-Mc1r+/+-HGF animals, they developed UV-induced and spontaneous melanomas with significantly less efficiency by all criteria. Thus, heterozygosity for Mc1r was sufficient to restore the transgenic HGF phenotype but insufficient to fully restore melanoma. We conclude that a previously unsuspected melanin-independent interaction between Mc1r and Met signaling pathways is required for HGF-dependent melanoma and postulate that this pathway is involved in human melanoma

    MicroRNAs and Drinking: Association between the Pre-miR-27a rs895819 Polymorphism and Alcohol Consumption in a Mediterranean Population

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    Recently, microRNAs (miRNA) have been proposed as regulators in the different processes involved in alcohol intake, and differences have been found in the miRNA expression profile in alcoholics. However, no study has focused on analyzing polymorphisms in genes encoding miRNAs and daily alcohol consumption at the population level. Our aim was to investigate the association between a functional polymorphism in the pre-miR-27a (rs895819 A>G) gene and alcohol consumption in an elderly population. We undertook a cross-sectional study of PREvencion con DIeta MEDiterranea (PREDIMED)-Valencia participants (n = 1007, including men and women aged 67 +/- 7 years) and measured their alcohol consumption (total and alcoholic beverages) through a validated questionnaire. We found a strong association between the pre-miR-27a polymorphism and total alcohol intake, this being higher in GG subjects (5.2 +/- 0.4 in AA, 5.9 +/- 0.5 in AG and 9.1 +/- 1.8 g/day in GG; p(adjusted) = 0.019). We also found a statistically-significant association of the pre-miR-27a polymorphism with the risk of having a high alcohol intake (> 2 drinks/day in men and > 1 in women): 5.9\% in AA versus 17.5\% in GG; p(adjusted) < 0.001. In the sensitivity analysis, this association was homogeneous for sex, obesity and Mediterranean diet adherence. In conclusion, we report for the first time a significant association between a miRNA polymorphism (rs895819) and daily alcohol consumption.This study was funded, by the Spanish Ministry of Health (Instituto de Salud Carlos III) and the Ministerio de Economia y Competitividad-Fondo Europeo de Desarrollo Regional (Projects CNIC-06/2007, RTIC G03/140, CIBER 06/03, PI06-1326, PI07-0954, PI11/02505, SAF2009-12304, AGL2010-22319-C03-03 and PRX14/00527), by the lUniversity Jaume I (Project P1-1B2013-54), by Contracts 53-K06-5-10 and 58-1950-9-001 from the U.S. Department of Agriculture Research Service, USA, by the Generalitat Valenciana (ACOMP2010-181, AP111/10, AP-042/11, ACOM2011/145, ACOMP/2012/190, ACOMP/2013/159 and ACOMP/213/165), and with the collaboration of the Real Colegio Complutense at Harvard University, Cambridge. MA, USA. Rocio Barragon's contract is funded by the Ayudas para la contratacion de personal investigador en formacion de caracter predoctoral, Programa ``VALencia Investigacion mas Desarrollo´´ (VALi+d). Conselleria d'Educacio, Investigacio, Cultura i Esport. Generalitat Valenciana, Spain (ACIF/2013/168).S

    Interpreting declines in HIV test positivity:an analysis of routine data from Zimbabwe's national sex work programme, 2009–2019

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    Introduction: Early diagnosis of HIV is critical for epidemic control. To achieve this, successful testing programmes are essential and test positivity is often used as a marker of their performance. The aim of this study was to analyse trends and predictors of HIV test positivity over time and explore how an understanding of seroconversion rates could build on our interpretation of this indicator among female sex workers in Zimbabwe. Methods: We analysed HIV test data from Zimbabwe's nationally scaled sex work programme between 2009 and 2019. We defined test positivity as the proportion of all tests that were HIV positive and measured new diagnoses by estimating seroconversion rates among women with repeat tests, defined as an HIV-positive test after at least one HIV-negative test in the programme. We used logistic regression to analyse test positivity over three time-periods: 2009–2013, 2014–2017 and 2018–2019, adjusting for potential confounding by demographic factors and the mediating effects of time since last HIV test. We calculated the seroconversion rates for the same time-periods. Results: During the 10-year study period, 54,503 tests were recorded in 39,462 women. Between 2009 and 2013, 18% of tests were among women who reported testing in the previous 6 months. By 2018–2019, this had increased to 57%. Between 2018 and 2019, test positivity was 9.6%, compared to 47.9% for 2009–2013 (aOR 6.08 95% CI 5.52–6.70) and 18.8% for 2014–2017 (aOR 2.17 95% CI 2.06–2.28). Adjusting for time since last test reduced effect estimates for 2009–2013 (aOR 4.03 95% CI 3.64–4.45) and 2014–2017 (aOR 1.97 95% CI 1.86–2.09) compared to 2018–2019. Among 7573 women with an initial HIV-negative test in the programme and at least one subsequent test, 464 tested HIV positive at a rate of 3.9 per 100 pyar (95% CI 3.5–4.2).Conclusions: Test positivity decreased among women testing through the programme over time, while seroconversion rates remained high. These declines were partly driven by changes in individual testing history, reflecting comprehensive coverage of testing services and greater knowledge of HIV status, but not necessarily declining rates of seroconversion. Understanding testing history and monitoring new HIV infections from repeat tests could strengthen the interpretation of test positivity and provide a better understanding of programme performance.</p

    Interpreting declines in HIV test positivity:an analysis of routine data from Zimbabwe's national sex work programme, 2009–2019

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    Introduction: Early diagnosis of HIV is critical for epidemic control. To achieve this, successful testing programmes are essential and test positivity is often used as a marker of their performance. The aim of this study was to analyse trends and predictors of HIV test positivity over time and explore how an understanding of seroconversion rates could build on our interpretation of this indicator among female sex workers in Zimbabwe. Methods: We analysed HIV test data from Zimbabwe's nationally scaled sex work programme between 2009 and 2019. We defined test positivity as the proportion of all tests that were HIV positive and measured new diagnoses by estimating seroconversion rates among women with repeat tests, defined as an HIV-positive test after at least one HIV-negative test in the programme. We used logistic regression to analyse test positivity over three time-periods: 2009–2013, 2014–2017 and 2018–2019, adjusting for potential confounding by demographic factors and the mediating effects of time since last HIV test. We calculated the seroconversion rates for the same time-periods. Results: During the 10-year study period, 54,503 tests were recorded in 39,462 women. Between 2009 and 2013, 18% of tests were among women who reported testing in the previous 6 months. By 2018–2019, this had increased to 57%. Between 2018 and 2019, test positivity was 9.6%, compared to 47.9% for 2009–2013 (aOR 6.08 95% CI 5.52–6.70) and 18.8% for 2014–2017 (aOR 2.17 95% CI 2.06–2.28). Adjusting for time since last test reduced effect estimates for 2009–2013 (aOR 4.03 95% CI 3.64–4.45) and 2014–2017 (aOR 1.97 95% CI 1.86–2.09) compared to 2018–2019. Among 7573 women with an initial HIV-negative test in the programme and at least one subsequent test, 464 tested HIV positive at a rate of 3.9 per 100 pyar (95% CI 3.5–4.2).Conclusions: Test positivity decreased among women testing through the programme over time, while seroconversion rates remained high. These declines were partly driven by changes in individual testing history, reflecting comprehensive coverage of testing services and greater knowledge of HIV status, but not necessarily declining rates of seroconversion. Understanding testing history and monitoring new HIV infections from repeat tests could strengthen the interpretation of test positivity and provide a better understanding of programme performance.</p

    Validation of the Regicor Short Physical Activity Questionnaire for the Adult Population

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    OBJECTIVE: To develop and validate a short questionnaire to estimate physical activity (PA) practice and sedentary behavior for the adult population. METHODS: The short questionnaire was developed using data from a cross-sectional population-based survey (n = 6352) that included the Minnesota leisure-time PA questionnaire. Activities that explained a significant proportion of the variability of population PA practice were identified. Validation of the short questionnaire included a cross-sectional component to assess validity with respect to the data collected by accelerometers and a longitudinal component to assess reliability and sensitivity to detect changes (n = 114, aged 35 to 74 years). RESULTS: Six types of activities that accounted for 87% of population variability in PA estimated with the Minnesota questionnaire were selected. The short questionnaire estimates energy expenditure in total PA and by intensity (light, moderate, vigorous), and includes 2 questions about sedentary behavior and a question about occupational PA. The short questionnaire showed high reliability, with intraclass correlation coefficients ranging between 0.79 to 0.95. The Spearman correlation coefficients between estimated energy expenditure obtained with the questionnaire and the number of steps detected by the accelerometer were as follows: 0.36 for total PA, 0.40 for moderate intensity, and 0.26 for vigorous intensity. The questionnaire was sensitive to detect changes in moderate and vigorous PA (correlation coefficients ranging from 0.26 to 0.34). CONCLUSION: The REGICOR short questionnaire is reliable, valid, and sensitive to detect changes in moderate and vigorous PA. This questionnaire could be used in daily clinical practice and epidemiological studies

    Temporal trends in, and risk factors for, HIV seroconversion among female sex workers accessing Zimbabwe's national sex worker programme, 2009–19:a retrospective cohort analysis of routinely collected HIV testing data

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    Background: The frequency of new HIV infections among female sex workers in sub-Saharan Africa is poorly understood. We used routinely collected data that enable unique identification of repeat HIV testers to assess temporal trends in seroconversion and identify associated risk factors for female sex workers accessing Sisters with a Voice, Zimbabwe's national sex worker programme. Methods: We pooled HIV testing data gathered between Sept 15, 2009, and Dec 31, 2019, from 36 Sisters programme sites in Zimbabwe. We included female sex workers aged 16 years or older with an HIV-negative test and at least one subsequent programme test. We calculated HIV seroconversion rates (using the midpoint between the HIV-positive test and the last negative test as the seroconversion date) and estimated rate ratios to compare 2-year periods by using Poisson regression, with robust SEs to account for clustering by site and adjusting for age and testing frequency to assess temporal trends. We did sensitivity analyses to explore assumptions about seroconversion dates and the effects of variation in follow-up time on our conclusions. Findings: Our analysis included data for 6665 female sex workers, 441 (7%) of whom seroconverted. The overall seroconversion rate was 3·8 (95% CI 3·4–4·2) per 100 person-years at risk. Seroconversion rates fell with time since first negative HIV test. After adjustment, there was evidence of a decrease in seroconversion rates from 2009 to 2019 (p=0·0053). In adjusted analyses, being younger than 25 years, and having a sexually transmitted infection diagnosis at a previous visit, were significantly associated with increased seroconversion rates. Our findings were mostly robust to sensitivity analyses, but when 1 month before an HIV-positive test was used as the seroconversion date, seroconversion rates no longer fell with time. Interpretation: We identified high rates of seroconversion shortly after linkage to programme services, which emphasises the need to strengthen HIV prevention programmes from first contact with female sex workers in Zimbabwe. New infections among female sex workers remain challenging to measure, but longitudinal analysis of routine testing data can provide valuable insights into seroconversion rates and associated risk factors. Funding: UN Population Fund, Deutsche Gesellschaft für Internationale Zusammenarbeit, the Bill &amp; Melinda Gates Foundation, The Global Fund to Fight AIDS, Tuberculosis and Malaria, US President's Emergency Plan for AIDS Relief, US Agency for International Development, and the Elton John AIDS Foundation.</p

    Renal Denervation Reduces Pulmonary Vascular Remodeling and Right Ventricular Diastolic Stiffness in Experimental Pulmonary Hypertension

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    Neurohormonal overactivation plays an important role in pulmonary hypertension (PH). In this context, renal denervation, which aims to inhibit the neurohormonal systems, may be a promising adjunct therapy in PH. In this proof-of-concept study, we have demonstrated in 2 experimental models of PH that renal denervation delayed disease progression, reduced pulmonary vascular remodeling, lowered right ventricular afterload, and decreased right ventricular diastolic stiffness, most likely by suppression of the renin-angiotensin-aldosterone system
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