Browsing by Author "Oliveira, Fernando Luiz Pereira de"

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    Abordagem multiobjetivo para otimização de redes de filas finitas.
    (2012) Cruz, Frederico Rodrigues Borges da; Oliveira, Fernando Luiz Pereira de; Ferreira, José Hissa; Magela Neto, Oriane
    Este artigo apresenta uma discussão sobre os resultados obtidos por meio de um algoritmo multiobjetivo recentemente desenvolvido para otimizar, simultaneamente, o tamanho total das áreas de espera, a taxa total de serviço e a taxa de saída de uma rede de filas finitas com serviço geral. Como tais objetivos eram conflitantes, utilizou-se uma versão de um algoritmo genético projetado para encontrar soluções ótimas a mais de um deles. Foram obtidas algumas propriedades que podem auxiliar na análise e no projeto de tais importantes sistemas estocásticos.
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    Adiposity indicators as a screening method for polysomnography in shift workers.
    (2019) Diniz, Amanda Popolino; Fajardo, Virgínia Capistrano; Freitas, Silvia Nascimento de; Oliveira, Fernando Luiz Pereira de; Nascimento Neto, Raimundo Marques do; Pimenta, Fausto Aloísio Pedrosa; Coelho, George Luiz Lins Machado
    Objective: to verify the discriminatory power of adiposity indicators in the prediction of obstructive sleep apnoea (OSA) in shift workers. Methods: a crosssectional study carried out in an iron ore extraction company, in Minas Gerais, Brazil. Anthropometric data were collected and polysomnography (PSG) was performed in 118 male shift workers who owned at least one overall risk factor for cardiovascular disease. Results: the OSA prevalence in the sample was 84.7%. Among the adiposity indicators used to predict OSA (≥ 5 events/hour), body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), and total body fat (TBF) showed sensitivity values higher than 70%. Visceral fat (VF), neck circumference (NC), and neck-to-height ratio (NHtR) were the most effective in correctly identifying workers without OSA (specificity values higher than 70%). The areas under the receiver operating characteristic (ROC) curves for WC and NHtR were greater than 0.7, which indicated the test was effective in discriminating individuals with OSA. Conclusions: alterations in abdomen and neck adiposity indicators have a significant relationship with the presence of OSA and showed effectiveness as a screening method for PSG. WC and NHtR are considered good indicators for OSA prediction.
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    Alta exigência no trabalho e alto risco cardiovascular em funcionários de uma universidade pública.
    (2017) Xavier, Helena Chaves; Damasceno, Eduardo Caires; Silqueira, Salete Maria de Fátima; Oliveira, Fernando Luiz Pereira de; Pimenta, Adriano Marçal
    Estimar a associação entre a alta exigência no trabalho e o elevado risco cardiovascular. Métodos: estudo epidemiológico transversal, desenvolvido com 211 trabalhadores do campus saúde de uma universidade pública do Estado de Minas Gerais. A alta exigência no trabalho foi definida com base no modelo demanda-controle de Karasek, enquanto o elevado risco cardiovascular, a partir do escore de Framingham. A associação entre a alta exigência no trabalho e o elevado risco cardiovascular foi estimada pela Razão de Prevalência (RP) e seu Intervalo de Confiança de 95% (IC 95%), ajustada por potenciais fatores de confusão e calculada por meio da regressão de Poisson. Resultados: a alta exigência no trabalho e o elevado risco cardiovascular estavam presentes em 28,4% e 28,0% dos participantes. Após a análise multivariada, a alta exigência no trabalho manteve-se associada ao elevado risco cardiovascular (RP = 3,67; IC 95%: 1,40-9,59). Conclusão: a prevalência do elevado risco cardiovascular foi alta nos trabalhadores expostos ao estresse psicoemocional no ambiente de trabalho. Portanto, esse achado deve ser considerado nas discussões sobre melhoria da qualidade de vida e na promoção da saúde dos trabalhadores com modificações no processo e nas relações de trabalho.
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    An item response theory approach to spatial cluster estimation and visualization.
    (2016) Cançado, André Luiz Fernandes; Gomes, Antonio E.; Silva, Cibele Queiroz da; Oliveira, Fernando Luiz Pereira de; Duczmal, Luiz Henrique
    The scan statistic is widely used in spatial cluster detection applications of inhomogeneous Poisson processes. The most popular variant of the spatial scan is the circular scan. However, such approach has several limitations, in particular, the circular window is not suitable to make the correct description of irregularly shaped and/or unconnected clusters. Additionally, such methodology does not incorporate the tools needed for quantifying the uncertainty in the description of the most likely cluster in the analysis. In the present work we build upon the previously proposed methodology called intensity function a more efficient and accurate way of defining the uncertainty in the identification of spatial clusters using Item Response Theory ideas. Using simulated data we show that the proposed method can correctly identify primary, secondary and irregular clusters.
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    Análise do desenvolvimento de um ambiente acadêmico de inovação.
    (2023) Damásio, Camila Alves; Silva, Sergio Evangelista; Pereira, Alana Deusilan Sester; Silva, Sergio Evangelista; Pereira, Alana Deusilan Sester; Oliveira, Fernando Luiz Pereira de; Freitas, Jonathan Simões
    As inovações criadas normalmente são o resultado da ação organizada de diversos atores e instituições (por exemplo, universidades, empresas, institutos de pesquisa, entre outros) em sistemas sociais complexos. Esses ambientes são normalmente caracterizados por redes sociais em diferentes níveis formadas por indivíduos com conhecimentos diferentes e complementares. As patentes podem ser consideradas uma importante manifestação da criação de inovações tecnológicas, pois são documentos formais que registram dados da invenção, seus inventores e as instituições detentoras dos seus direitos de propriedade intelectual. Dessa maneira, este estudo buscou responder à seguinte questão de pesquisa: Como os ambientes acadêmicos de inovação se desenvolvem ao longo do tempo? Sendo assim, o objetivo geral desta pesquisa é investigar como os ambientes acadêmicos de inovação se desenvolvem no tempo, a partir da interação das equipes de pesquisadores/inventores. Para entender melhor o processo de criação de inovações tecnológicas, foram utilizadas as lentes teóricas dos sistemas sociais de inovação. O objeto de estudo consistiu na Faculdade de Medicina de Ribeirão Preto, da Universidade de São Paulo (USP), cujo desenvolvimento de sua capacidade inovadora foi pesquisado por meio dos dados de 93 patentes produzidas em seu ambiente entre os anos de 1988 e 2020. A pesquisa utilizou-se de fontes documentais e baseou-se na coleta de dados dos atores deste ambiente. Como principal resultado, destaca-se que a patente envolve diversos atores; em vários casos, há a reunião de conhecimentos diferentes e complementares advindas de diferentes unidades acadêmicas e não acadêmicas. Esta pesquisa concluiu que no decorrer do tempo os pesquisadores passaram, cada vez mais, a formar equipes entre si para a criação das patentes, demonstrando a importância da troca de conhecimento. Como contribuição para a teoria, este estudo analisa como se desenvolvem os ambientes acadêmicos de inovação. De uma perspectiva prática, esta pesquisa aponta insights e diretrizes que podem guiar a formação e desenvolvimento de novos ambientes acadêmicos de inovação.
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    Análise espaço-temporal aplicada às ocorrências de hipertensão e diabetes nos municípios do estado de Minas Gerais.
    (2014) Pinto, Eliangela Saraiva Oliveira; Santos, Gerson Rodrigues dos; Oliveira, Fernando Luiz Pereira de
    Objetivando avaliar a distribuição espaço-temporal de hipertensão arterial e diabetes mellitus nos municípios de Minas Gerais, entre 2002 a 2012, aplicou-se as técnicas de análise espacial de dados de área, destacando-se a média móvel local, os coeficientes de autocorrelação global de Moran e o índice local de Moran. Além disso, foram construídos mapas temáticos de distribuição espacial, de autocorrelação local (Box Map) e de identificação de cluster, utilizando a estatística Scan espaço-temporal. Verificou-se que há autocorrelação espacial para ambas as variáveis, entre os municípios, em que apresentou coeficientes de Moran (global) positivos e significativos para todos os anos estudados. Foi possível identificar, por meio da análise local, agrupamento de municípios situados na parte sul do estado com maiores taxas de prevalência de hipertensão e também de diabetes em todos os anos. Também identificou-se a ocorrência de cluster significativo localizado no sul do estado para as duas variáveis analisadas. Conclui-se que a análise espaço-temporal permitiu mapear e compreender a distribuição das taxas de hipertensão e diabetes no estado de Minas Gerais. Estudos como este podem fornecer informações para que os serviços de saúde possam selecionar os principais locais com taxas altas e propor ações de controle.
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    Anti-helminthic activity of Momordica charantia L. against Fasciola hepatica eggs after twelve days of incubation in vitro.
    (2016) Pereira, Cíntia Aparecida de Jesus; Oliveira, Laura Lúcia dos Santos; Lucas, Aytube Coaglio Silva; Santos, Fernanda Stéfani Oliveira dos; Cezar, Rodolfo Silva Moreira; Mendes, Tiago Antônio de Oliveira; Oliveira, Fernando Luiz Pereira de; Cosenza, Gustavo Pereira; Lima, Walter dos Santos
    Fasciolosis, a parasitic disease caused by the trematode Fasciola hepatica underreported is expanding both in human and animal population, throughout the world. The constant use of synthetic drugs to treat this condition has led to the natural selection of resistant strains of the parasite. Hence, there is a growing focus on the potential anti-helminthic properties of medicinal plants and phytopharmaceuticals. The current study assessed the potential anti-fasciolicide action of Momordica charantia leaf extracts and fractions on the eggs of F. hepatica parasites. The lyophilized crude extract (CE) of M. charantia leaves and its sub-fractions, obtained from liquid–liquid partitioning with organic solvents, were analysed by High Performance Liquid Chromatography (HPLC), suspended in 1% DMSO and used in in vitro tests. Quadruplicates of 50 F. hepatica eggs were incubated at 23 ◦C with M. charantia leaf CE in different concentrations. After 12 days no larvae were formed in eggs incubated with CE concentrations above 12.5 mg/mL. Eggs incubated with CE sub-fractions at concentrations of 1000, 100, 10, 1, 0.1, 0.01 g/mL affected embryonic development, with n-butanol presenting the strongest inhibition of miracidia formation. In contrast, on the 12th day, 90% of the miracidia hatched in the control experiments using 0.03% DMSO whereas embryogenesis was completely abolished with any concentration of albendazole sulphoxide ABZ(SO). Chemical analysis of the CE and sub-fractions revealed a prominent presence of flavonoids. HPLC–MS confirmed Quercetin to be one of the main flavonoids present in the CE and the n-butanol subfraction. This is the first study to analyse the potential anti-fasciolicide action of M. charantia leaf CE and subfractions.
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    Association between nutritional status, C-reactive protein, adiponectin and HOMA-AD in Brazilian children.
    (2014) Domingos, Ana Luiza Gomes; Coelho, George Luiz Lins Machado; Volp, Ana Carolina Pinheiro; Oliveira, Fernando Luiz Pereira de; Caldas, Ivo Santana; Freitas, Silvia Nascimento de
    Introduction: In children, the presence of obesity is a major risk factor for the occurrence of cardiovascular diseases on the adulthood. Objective: To evaluate the association of anthropometry, body composition, clinical variables and biochemical profile with C-reactive protein and adiponectin levels, and insulin resistance in children in the municipality of Nova Era, Brazil. Methods: Nested case-control study following a crosssectional study. We evaluated 178 children, 57 of them classified as obese and 121 as normal-weight from a population of 1024 schoolchildren 6 to 10 years old: Blood samples were collected after 12-hour fast to obtain serum and plasma. We collected anthropometric and body composition measures, systolic and diastolic blood pressure data. Sexual maturation was assessed according to the stage of sexual development. We performed Student’s t-test, Mann-Whitney U test, Pearson’s correlation, Spearman’s test and multiple linear regression analysis. Independent variables with p < 0.05 were included in the multiple regression model. Residual analysis was performed to assess model validity. Results: Among obese children, C-reactive protein levels were associated with triacylglycerol levels and body fat percentage estimated by skinfold thickness (R2 adjusted = 27.6%, p < 0.001). Adiponectin was associated with HOMA-IR, HOMAAD and body fat percentage estimated by skinfold thickness (R2 adjusted = 75.5%, p < 0.001). HOMA-AD index was associated with HOMA-IR, adiponectin, systolic blood pressure and weight (R2 adjusted = 90.7%, p < 0.001). Conclusion: Significant associations were found between body composition, anthropometry, clinical variables, biochemical profile and adiponectin and C-reactive protein levels and insulin resistance in obese and normal-weight children.
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    Association of hypovitaminosis d with sleep parameters in rotating shift worker drivers.
    (2023) Menezes Junior, Luiz Antonio Alves de; Fajardo, Virgínia Capistrano; Nascimento Neto, Raimundo Marques do; Freitas, Silvia Nascimento de; Oliveira, Fernando Luiz Pereira de; Pimenta, Fausto Aloísio Pedrosa; Coelho, George Luiz Lins Machado; Meireles, Adriana Lúcia
    Objective To evaluate the association between sleep parameters and hypovitami- nosis D in rotating shift drivers. Material and Methods We conducted a cross-sectional study on 82 male rotating shift workers (24–57 years old) with at least one cardiovascular risk factor (such as hyperglycemia, dyslipidemia, abdominal obesity, physical inactivity, hypertension, and smoking). Polysomnography was used to evaluate sleep parameters. Logistic regres- sion was used to model the association between hypovitaminosis D and sleep parameters after adjustment for relevant covariates. Results Hypovitaminosis D (< 20 ng/mL) was seen in 30.5% of the workers. Shift workers with hypovitaminosis D had lower sleep efficiency (odds ratio [OR]: 3.68; 95% confidence interval [CI]: 1.95–5.53), lower arterial oxygen saturation (OR: 5.35; 95% CI: 3.37–6.12), and increased microarousal index (OR: 3.85; 95% CI: 1.26–5.63) after adjusting. Conclusion We suggest that hypovitaminosis D is associated with greater sleep disturbances in rotating shift workers.
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    Avaliação de impactos ambientais na rodovia MG - 010 : estudo de caso no vetor norte de Belo Horizonte (MG).
    (2013) Brito, Tiago Silva Alves de; Vasconcellos, Fernanda Carla Wasner; Oliveira, Fernando Luiz Pereira de
    O presente trabalho tem por objetivo avaliar os impactos ambientais da Rodovia MG – 010 no trecho entre Hospital Risoleta Neves até o Viaduto Avenida Senhor do Bonfim (início da MG – 424), localizada no município de Belo Horizonte (MG), no período de 1989 e 2010. Para dar base aos estudos utilizaram-se os softawares Global Mapper e ArcGis para confecção dos mapas temáticos da área, e, ainda, registro fotográfico in loco dos principais impactos as margens da rodovia. Os resultados demonstraram que em um período de 20 anos a MG – 010 sofreu alterações em todos os compartimentos ambientais: físico (surgimento de ravinas e voçorocas), biótico (introdução de espécies exóticas e aumento das áreas de mata) e socioeconômico (aumento da circulação de veículos, atração de comércios e serviços e alargamento das autovias). Dentre os fatores que contribuíram para o desencadeamento deste processo está a expansão urbana-industrial direcionada ao Vetor Norte de Belo Horizonte.
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    Bias correction for estimation of performance measures of a Markovian queue.
    (2017) Almeida, Marcio Augusto da Cruz; Cruz, Frederico Rodrigues Borges da; Oliveira, Fernando Luiz Pereira de; Souza, Gustavo Henrique Costa de
    There are several situations in our daily lives in which queues are present, such as cafeterias, supermarkets, banks, gas stations, and so forth. The performance of such queues can be described by several measures. In this article, the focus is on estimates of traffic intensity ( ρ ), also called the utilization factor of the service station, the expected number of customers in the system (L), and the average queue size ( Lq ) for infinite single-serve queues with Poisson arrivals and exponential (Markovian) service times. The computational experiments show that the maximum likelihood estimators (MLEs) of the performance measures are biased for small and moderate samples ( n<50 ). Thus, a version corrected by the nonparametric bootstrap method is analyzed, demonstrating that researchers could achieve with an extra computational effort bias-corrected estimates for samples of size n=10 with average errors equivalent to the estimates from the MLE for samples of size n=200 . This reduction can be very important in practical applications because of the cost and time reduction that it may bring to the process of estimating the performance measures of a queueing system.
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    Bilingualism effects on L1 representation and processing of argument structure.
    (2017) Oliveira, Cândido Samuel Fonseca de; Souza, Ricardo Augusto de; Oliveira, Fernando Luiz Pereira de
    This study aims to investigate L2-to-L1 cross-linguistic influence on bilinguals’ representation and processing with three psycholinguistics tasks. The interest in this type of effect lies in its possible association with cognitive control development. Our study focuses on possible influences of the non-dominant language on the dominant language: we analyzed whether highly proficient Brazilian Portuguese-English late bilinguals immersed in the L1 context behaved differently from Brazilian Portuguese monolinguals in regards to sentences in the L1 that simulated an L2-specific construction (true resultative). We conducted a maze task in order to analyze the speakers’ linguistic processing and a speeded acceptability judgment task in order to analyze their linguistic representation. We also observed participants’ behavior towards a construction available in both languages (depictive). The overall results indicate that bilinguals processed both constructions faster than monolinguals, but the difference between the groups was significantly larger towards the true resultative construction. However, there was no significant difference between the groups in relation to how they perceived the acceptability of both constructions. We interpret the results as evidence that the L2 influence on the L1 occurs during real time sentence processing, but it does not result in changes in the overall L1 representation.
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    Body fat indicators for cardiometabolic risk screening among shift workers.
    (2020) Diniz, Amanda Popolino; Alves, Márcia Elivane; Fajardo, Virgínia Capistrano; Freitas, Silvia Nascimento de; Batista, Guilherme Augusto Sousa; Athadeu, Bruno Francia Maia; Coelho, George Luiz Lins Machado; Oliveira, Fernando Luiz Pereira de; Pimenta, Fausto Aloísio Pedrosa; Nascimento Neto, Raimundo Marques do
    Background: In view of the costly methods currently available for the assessment of body adiposity, anthropometric obesity indicators have proven effective in predicting cardiovascular risk. Objective: To investigate the discriminatory power of body fat indicators for cardiovascular risk screening among shift workers. Methods: Cross-sectional study with male employees of an iron ore extraction company. The predictive power of body fat indicators relative to cardiovascular risk was analyzed based on the Framingham risk score and metabolic syndrome by means of receiver operating characteristic curves, sensitivity, specificity, positive and negative predictive values, area under the receiver operating characteristic curve and Youden’s index. Results: The prevalence of cardiovascular risk was 14.2% in the metabolic syndrome risk model. According to the Framingham score, 95.0%, 4.1% and 0.9% of the participants exhibited low, moderate and high risk, respectively. All the analyzed body fat indicators exhibited satisfactory discriminatory power for the tested cardiovascular risk models. Conclusion: Waist-height ratio exhibited the highest ability to predict cardiometabolic risk in both risk models.
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    Built and social environments and overweight among Brazilian adults from medium-sized city : CUME Project.
    (2022) Domingos, Ana Luiza Gomes; Hermsdorff, Helen Hermana Miranda; Mendes, Larissa Loures; Oliveira, Fernando Luiz Pereira de; Oliveira, Anderson Castro Soares de; Pimenta, Adriano Marçal; Bressan, Josefina
    A cross-sectional study enrolled participants from the CUME project (n = 289) who lived in Viçosa, Brazil. The neighborhood unit adopted was the buffer (200 meters), considering the participant’s residence as central point. We measure the number of public and private facilities inside the buffer as well as violent criminal occurrences. Food establishments were categorized into establishments with predominant sale of natural or minimally processed foods, mixed establishments, and establishments with predominant sale of ultra-processed foods. Those who attended the face-to-face interview filled two scales of perception of the environment. Overall, 33.6% of participants reported overweight. We observed a higher concentration of individuals close to the central region of the city. Access to different establishments, food environments, and criminal occurrences differed between normal-weight and overweight individuals. The groups deferred in the perception of the location of squares, open public spaces, clubs, and soccer fields. The results indicate the association between environmental characteristics and overweight in Brazilian adults.
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    Cardiovascular risk factors in haul truck operators of the mining sector working a rotational schedule.
    (2021) Marques, Rafaela Aparecida Mendonça; Camargo, Priscila Pena; Souza, Gabriela Guerra Leal de; Gouvêa, Graziela Dutra Rocha; Fajardo, Virgínia Capistrano; Nascimento Neto, Raimundo Marques do; Silva, André Luis; Oliveira, Fernando Luiz Pereira de
    Background: Due to the growing concern about work-related social and health aspects , occupational health and safety has become relevant. Objective: This work aims to develop a model to assist cardiovascular risk management in a team of haul truck operators, who work in rotating shifts at a mining company in Brazil. Methods: This longitudinal study evaluated risk factors for cardiovascular diseases of 191 mineworkers at three times points – 2010, 2012, and 2015. In addition, the risk of developing cardiovascular diseases was calculated, and the risk factors were analyzed using the chi-square test, the U Mann-Whitney test, and binary logistic regression. The significance level was set at 5%. Results: In the study period, body weight, body mass index (BMI), waist-to-height ratio (WHR), systolic (SBP), and diastolic blood pressure (DBP), total cholesterol, high-density lipoprotein cholesterol (HDL-C), and triglycerides levels of the study group increased. In 2015, there was a high prevalence of alcohol intake, overweight or obesity, central obesity, inadequate WHR, high blood pressure, total cholesterol above 190 mg/dL, and triglycerides above 150 mg/dL. An association was identified between increased cardiovascular risk and age, SBP, HDL-C, low-density lipoprotein cholesterol (LDL-C), and elevated glucose levels. Conclusion: Intense interventions for reduction and prevention of elevated alcohol intake, blood pressure levels, WHR, metabolic syndrome, blood glucose, and LDL-C levels, and low HDL-C levels are needed. In addition, a close monitoring of mine workers over 38 years of age who smoke, consume alcoholic beverages, and have altered blood glucose levels is important.
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    Chisquaremax rotation criterion in factor analysis : a Monte Carlo assessment of the effect of outliers.
    (2014) Pereira, Tiago Martins; Cirillo, Marcelo Ângelo; Oliveira, Fernando Luiz Pereira de
    Recentemente, Knüsel (2008) propôs um novo método de rotação ortogonal, denominado por critério Chisquaremax, baseado na estatística qui-quadrado, o desempenho desse critério não foi avaliado em relação ao efeito de outliers. Frente à esta questão, este trabalho teve por objetivo estudar o modelo fatorial utilizando o critério de rotação Chisquaremax em relação ao efeito de outliers, servindo-se de técnicas de simulação Monte Carlo em diferentes cenários. Concluiu-se que a eficiência do estimador da matriz de covariância proporcionada pelo modelo fatorial utilizando o critério Chisquaremax e Promax não foi afetada pela presença de outliers. O modelo fatorial ortogonal aplicando o critério Chisquaremax apresentou melhores índices de qualidade de ajuste em comparação aos resultados obtidos para o critério Promax.
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    Chronic fatigue syndrome and its relation with absenteeism : elastic-net and stepwise applied to biochemical and anthropometric clinical measurements.
    (2021) Neisse, Anderson Cristiano; Oliveira, Fernando Luiz Pereira de; Oliveira, Anderson Castro Soares de; Cruz, Frederico Rodrigues Borges da; Nascimento Neto, Raimundo Marques do
    Characterized by persistent fatigue, pain, cognitive impairment and sleep difficulties, Chronic Fatigue Syndrome (CFS) has been common in clinical practice. Studies indicate multiple factors contributing to CFS development: poor sleep, dehydration, psychological stress, hormonal dysfunction, nutrient deficiencies, among others. In risk work conditions, like the shift work of mines, CFS significantly increases the chance of fatal accidents. Work environments of mines suggest the presence of factors that increase the risk of developing CFS. Considering the severity/implications of CFS’s symptoms on the social and professional lives as well as on the economy, efforts are targeting its characterization and prevention. This study aims to assess the risk of CFS by studying cross-sectional data on absenteeism of 621 shift workers, measuring 8 anthropometric and 11 biochemical variables as well as age and gender, amounting 21 variables. After imputation, logistic regression was fitted by Stepwise selection, Lasso and Elastic-Net regularization. Results suggest that the models do not discriminate very well due to noise inherent to the dependent variable. However, all models agree on the effects of Sodium and Total Cholesterol on the risk of absenteeism. The Stepwise model also indicates LDL and Triglycerides as significant factors, both Lasso and Elastic-Net show effects for LDL instead. The Elastic-Net model suggests an effect of Potassium, though inconclusive according to the literature.
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    Clustered cardiovascular risk factors are associated with inflammatory markers in adolescents.
    (2017) Silva, Carla Teixeira; Cândido, Ana Paula Carlos; Pala, Daniela; Barbosa, Priscila Oliveira; Coelho, George Luiz Lins Machado; Oliveira, Fernando Luiz Pereira de; Volp, Ana Carolina Pinheiro; Freitas, Renata Nascimento de
    Background: Clusters of cardiovascular risk (CVR) factors are associated with an increased risk of developing cardiovascular diseases (CVDs). This cross-sectional study assessed the associations between classic CVR factor clusters and inflammatory markers in Brazilian adolescents. Methods: Measurements included anthropometric, clinical and biochemical parameters and selected inflammatory markers in 487 adolescents (236 boys/251 girls; 12.06 ± 1.41 years). Results: After stratifying the population by gender and adjusting for potential confounding variables, principal component analysis was performed and it produced 5 independent components in both genders: adiposity, glucose metabolism, blood pressure, high-density lipoprotein (HDL)/triacylglycerols (TG), and cholesterol/low-density lipoprotein. Glucose metabolism was inversely associated with interleukin-1β (IL-1β) in both genders ( r = –0.026; r = –0.021); blood pressure was inversely associated with tumor necrosis factor alpha (TNF-α) in girls ( r = –0.046); HDL/TG was positively associated with interleukin-6 in girls ( r = 0.012), with IL-1β ( r = 0.010) TNF-α ( r = 0.045) in boys, and inversely associated with adiponectin in both genders ( r = –0.015; r = –0.013). Conclusion: The results suggest that lipid metabolism alterations, as potential early events in the development of CVDs, have a strong link to the inflammatory process, in contrast to other clusters of risk factors.
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    Cohort profile : the cohort of universities of Minas Gerais (CUME).
    (2018) Domingos, Ana Luiza Gomes; Miranda, Aline Elizabeth da Silva; Pimenta, Adriano Marçal; Hermsdorff, Helen Hermana Miranda; Oliveira, Fernando Luiz Pereira de; Santos, Luana Caroline dos; Lopes, Aline Cristine Souza; Martínez González, Miguel Ángel; Bressan, Josefina
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    Comparing the inertial effect of MEWMA and multivariate sliding window schemes with confidence control charts.
    (2016) Moraes, D. A. O.; Oliveira, Fernando Luiz Pereira de; Duczmal, Luiz Henrique; Cruz, Frederico Rodrigues Borges da
    In practical applications of multivariate sliding window (SW) control charts, a considerable amount of difficulty lies in selecting parameters related to the window size and to the disposal of past observations. Although widely used for pattern recognition problems, to the best of the authors’ knowledge, there have been no comparative analyses of the efficiencies of multivariate SW schemes and more traditional and easy-to-apply control charts, such as Hotelling’s T 2 and the multivariate exponentially weighted moving average (MEWMA) control charts. The present work applies a transformed statistic called confidence control chart (CCC), which standardizes all the control charts in the 0–1 interval to improve visualization, and comparisons are made in terms of the average run length (ARL). Therefore, the purpose of this paper is to present a simulation study to compare the inertial effect of estimating the actual mean vector through the SW and the MEWMA schemes. Three types of SW schemes were tested, including uniform, linear, and exponential weights. In addition to providing equivalences between the smoothing parameter of the MEWMA method and the window sizes for the bivariate case, the results show that multivariate SW schemes suffer from the inertial effect more than MEWMA charts. In this sense, the user is encouraged to apply both control charts to avoid detection delay.