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Regression model for the reported infected during emerging pandemics under the stochastic SEIR.
(2023) Silva, Ivair Ramos; Zhuang, Yan; Bhattacharjee, Debanjan; Almeida, Igor Ribeiro de
The COVID-19 pandemic revealed the necessity of measuring the statistical relationship between the transmission rate of epidemic diseases and the social/behavioral, logistical, and economic variables of the affected region. This paper introduces a regression model to estimate the impact of such covariates on the infectious rate of epidemiological agents. Hidden logistical predictor components, such as weekly seasonality of reported data, can also be accessed with the proposed methodology. For this, we assume that the dynamics of officially reported data of emerging pandemics, related to infected groups, follows a stochastic SEIR model. The main advantage of our method is that it is based on a new three- step algorithm that combines the classical likelihood principle, the minimization of the mean squared error, and a tri-section algorithm to estimate, simultaneously, the coefficients of the covariates and the parameters of the compartmental model. Simulation studies are provided to certify the accuracy of the proposed inference methodology. The model is further applied to analyze the official statistical reports of COVID-19 data in the state of São Paulo, Brazil.
Fixed-length interval estimation of population sizes : sequential adaptive Monte Carlo mark–recapture–mark sampling.
(2023) Silva, Ivair Ramos; Bhattacharjee, Debanjan; Zhuang, Yan
Mark–recapture sampling schemes are conventional approaches for population size (N) estimation. In this paper, we mainly focus on providing fixed-length confidence interval estimation methodologies for N under a mark–recapture–mark sampling scheme, where, during the resampling phase, non-marked items are marked before they are released back in the population. Using a Monte Carlo method, the interval estimates for N are obtained through a purely sequential procedure with an adaptive stopping rule. Such an adaptive deci- sion criterion enables the user to “learn” with the subsequent marked and newly tagged items. The method is then compared with a recently developed accelerated sequential procedure in terms of coverage probability and expected number of captured items during the resampling stage. To illustrate, we explain how the proposed procedure could be applied to estimate the number of infected COVID-19 individuals in a near-closed population. In addition, we present a numeric application inspired on the problem of estimating the population size of endangered monkeys of the Atlantic forest in Brazil.
Bounded-width confidence interval following optimal sequential analysis of adverse events with binary data.
(2022) Silva, Ivair Ramos; Zhuang, Yan
In sequential testing with binary data, sample size and time to detect a signal are the key performance measures to opti- mize. While the former should be optimized in Phase III clinical trials, minimizing the latter is of major importance in post- market drug and vaccine safety surveillance of adverse events. The precision of the relative risk estimator on termination of the analysis is a meaningful design criterion as well. This paper presents a linear programming framework to find the optimal alpha spending that minimizes expected time to signal, or expected sample size as needed. The solution enables (a) to bound the width of the confidence interval following the end of the analysis, (b) designs with outer signaling thresh- olds and inner non-signaling thresholds, and (c) sequential designs with variable Bernoulli probabilities. To illustrate, we use real data on the monitoring of adverse events following the H1N1 vaccination. The numerical results are obtained using the R Sequential package.
Association of hypovitaminosis d with sleep parameters in rotating shift worker drivers.
(2023) Menezes Júnior, Luiz Antônio 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.
Effects of minimally and ultra-processed foods on blood pressure in Brazilian adults : a two-year follow up of the CUME project.
(2023) Alves, Katiusse Rezende; Hermsdorff, Helen Hermana Miranda; Miranda, Aline Elizabeth da Silva; Bressan, Josefina; Mendonça, Raquel de Deus; Oliveira, Fernando Luiz Pereira de; Pimenta, Adriano Marçal
Aim: To assess the association of food consumption according to degree of processing with changes in systolic (SBP) and diastolic (DBP) blood pressure in adult participants of a Brazilian cohort. Methods: Longitudinal study with 2496 adult participants of the Cohort of Universities of Minas Gerais (CUME Project). Food consumption was categorized by food groups according to degree of processing following the NOVA grading system: unprocessed/minimally processed foods/culinary ingredients (U/MPF&CI), processed foods (PFs) and ultra-processed foods (UPFs). unprocessed/ minimally processed foods/culinary ingredients (U/MPF&CI), processed foods (PFs) and ultra-processed foods (UPFs). Changes in SBP and DBP were categorized (decreased, maintained, increased). Independent associations between exposure and outcomes were verified using multiple generalized ordered logistic models adjusted for potential confounders. Results: After a two-year follow-up, the consumption of U/MPF&CI (% daily caloric intake) reduced the chance of increasing DBP (P for trend ¼ 0.014), with a more evident effect among participants within the 5th quintile of this food group (odds ratio (OR) ¼ 0.55; 95% confidence interval (CI): 0.34–0.97]. On the other hand, the consumption of UPFs (% daily caloric intake) raised the chance of increasing DBP (P for trend ¼ 0.005) and was more evident among participants within the quintiles of higher consumption (4th quintile – OR ¼ 1.97; 95% CI: 1.25–3.10; 5th quintile – OR ¼ 1.79; 95% CI ¼ 1.12– 2.86). No associations were found between food consumption according to degree of processing and changes in SBP. Conclusion: Higher consumption of U/MPF&CI and UPFs were independently associated to lower and greater chances of increased DBP in adult participants from CUME Project.
Ultra-processed food consumption and dietary, lifestyle and social determinants : a path analysis in Brazilian graduates - CUME project.
(2022) Mattar, Jéssica Bevenuto; Domingos, Ana Luiza Gomes; Hermsdorff, Helen Hermana Miranda; Juvanhol, Leidjaira Lopes; Oliveira, Fernando Luiz Pereira de; Pimenta, Adriano Marçal; Bressan, Josefina
Objective: To explore the relationship between ultra-processed foods (UPF) con- sumption and dietary, lifestyle and social determinants using pathway analysis in the baseline of the Cohort of Universities of Minas Gerais (CUME project). Design: Cross-sectional study, in which path analysis was used to estimate direct and indirect effects of dietary practices, sleep, time on the computer and profes- sional status on UPF consumption. Setting: Data were collected in 2016, through an online questionnaire composed of sociodemographic, anthropometric, lifestyle and dietary practices questions, and a FFQ. Participants: Baseline participants from the CUME Project (n 2826), adults who graduated from Universidade Federal de Viçosa or Universidade Federal de Minas Gerais, Brazil. Results: Being employed (P = 0·024), the time spent on the computer (P = 0·031) and the frequency of fried food intake (P < 0·001) were positively and directly associated with UPF consumption, whereas the sleep duration (P = 0·007) and the number of meals per d (P < 0·001) were negatively and directly associated with UPF consumption. Indirect effects were observed between being employed, medi- ated by the sleep duration (P = 0·032) and fried food intake (P = 0·005), whereas being a student is mediated by the time on the computer (P = 0·048). Conclusion: The time spent on the computer, sleep duration and fried food con- sumption showed direct effects on UPF consumption. They also acted as mediators on the relationship between professional status and UPF consumption. Besides, the number of meals eaten each day also was directly associated with UPF consumption.
Neuroserpin : a potential biomarker for early-onset severe preeclampsia.
(2023) Perucci, Luiza Oliveira; Silva, Sirlaine Pio Gomes da; Bearzoti, Eduardo; Pinto, Kelerson Mauro de Castro; Alpoim, Patrícia Nessralla; Pinheiro, Melina Barros; Godoi, Lara Carvalho; Moraes, Lauro Ângelo Gonçalves de; Sousa, Lirlândia Pires de; Dusse, Luci Maria Sant'Ana; Silva, André Talvani Pedrosa da
Preeclampsia is a hypertensive disease of pregnancy associated with intense inflammatory and pro-coagulant responses. Neuroserpin is a serine protease inhibitor that has been involved in neurological and immune pro- cesses and has not yet been investigated in preeclampsia. Herein, we evaluated neuroserpin levels in association with other inflammatory mediators (IL-17A, IL-33, and CXCL-16) during severe preeclampsia. The mediators’ plasma levels were measured by immunoassays in 24 pregnant women with severe preeclampsia (early pre- eclampsia: N = 17, late preeclampsia: N = 7), 34 normotensive pregnant women, and 32 non-pregnant women. In general, pregnancy was associated with higher levels of neuroserpin, IL-17A, IL-33, and CXCL-16 than the non- pregnant state. However, this increase was attenuated in pregnancies complicated by severe preeclampsia. Although neuroserpin levels did not differ between normotensive pregnant women and pregnant women with severe preeclampsia, neuroserpin levels tended to be lower in early-onset than in late-onset severe preeclampsia. There were positive correlations between neuroserpin and IL-17A, neuroserpin and CXCL-16, and IL-17A and CXCL-16 levels in women with severe preeclampsia. In addition, although the risk for developing severe pre- eclampsia was higher in older women in this study, maternal age did not significantly influence the mediators’ levels, nor their correlations in the preeclampsia group. In summary, our data suggest that neuroserpin might be a potential biomarker for early-onset severe preeclampsia and, that the imbalance among neuroserpin, IL-17A, IL-33, and CXCL-16 levels may be associated with the pathogenesis of preeclampsia, regardless of the maternal age.
Similar inflammatory adaptation in women following 10 weeks of two equalized resistance training with different muscle action duration.
(2022) Pinto, Kelerson Mauro de Castro; Diniz, Rodrigo César Ribeiro; Tourino, Frank Douglas; Lacerda, Lucas Túlio de; Bearzoti, Eduardo; Costa, Karine Beatriz; Souza, Débora Maria Soares de; Lima, Fernando Vitor; Vieira, Etel Rocha; Chagas, Mauro Heleno; Silva, André Talvani Pedrosa da
This study is aimed at evaluating the profile of inflammatory markers and components of redox regulation in untrained women after 10 weeks of resistance training using equalized protocols but different muscle action duration (MAD). Twenty-two women underwent progressive resistance training exercising the knee extensor muscles for 10 weeks—3x/week, with 3-5 sets of 6 repetitions at 50% of the 1 repetition maximum strength test (1RM), with a rest of 180 s between the series, following the training protocol (i) 5 s of concentric muscle action for 1 s of eccentric muscle action (5C-1E) and (ii) 1 s of concentric muscle action for 5 s of eccentric muscle action (1C-5E). Quadriceps muscle hypertrophy maximum strength (1RM) and redox regulation/muscle damage/inflammatory markers (CAT, SOD, TBARS, FRAP, CH, LDH, CXCL8, and CCL2) were evaluated. Plasma markers were evaluated before and 30 minutes after the first and last training sessions. A similar gain in hypertrophy and maximum strength was observed in both groups. However, in the 5C-1E, a significant major effect was observed for SOD (F1:19 = 10:480, p = 0:004) and a significant major time effect, with a reduction in the last training session, was observed for CXCL8 (F1:37 = 27:440, p < 0:001). In conclusion, similar protocols of resistance training, with different MAD, produced similar inflammatory and adaptive responses to strength training. As the training load is progressive, the maintenance of this inflammatory and redox regulation profile suggests an adaptive response to the proposed strength training.
Ghost fat : altered female body perception after bariatric surgery.
(2023) Souza, André Luiz Lacerda; Souza, Perciliany Martins de; Mota, Bruna Eugênia Ferreira; Xavier, Christian Luiz Ferreira; Santiago, Fernando Gusmão; Oliveira, Juliano Silva; Borges, Samir Almeida; Bearzoti, Eduardo; Gama, Eliane Florencio; Souza, Gabriela Guerra Leal de
Body perception is an individual’s ability to recognize their body in attitudinal and/or dimensional aspects. We investigated women’s body perceptions before and after bariatric surgery. Participants were 31 women (M age = 36.23, SD = 7.95 years old) with an average pre-operative body mass index of 44.58 (SD = 4.65) kg/m2 . We collected anthropometric and body perception measures (attitudinal body image [ABI] and dimensional body image [DBI]) before bariatric surgery and 30, 60, 90, and 120 days after it. There was an average decrease of 21.09% in participants’ body weight over the 120 days. Regarding ABI, 51.61% of participants had high body dissatisfaction before surgery, and this proportion of dissatisfied participants decreased to 3.23% 120 days after surgery. We observed no statistically significant differences in DBI perceptions. Fast weight loss caused by bariatric surgery appeared to generate a perception of ghost fat. Somatosensory interventions and/or a longer follow-up are needed to alter this persistent distortion of body dimensions.
Quem é o vencedor entre o futebol e o desempenho financeiro?
(2023) Duarte, Anderson Ribeiro; Barbosa, Josino José; Martins, Helgem de Souza Ribeiro; Amorim, Gabriel Vieira de
A cada dia, cifras financeiras mais vultosas são envolvidas nos esportes de alto rendimento. Particularmente, no futebol, os valores são realmente surpreendentes. Diante desse contexto, uma pergunta impactante vem à tona, “quem de fato vence as competições esportivas, o desempenho puramente esportivo, ou é o desempenho financeiro?” Termos como doping financeiro, marketing da bola na rede, entre outros, surgem pelo mundo. Aliado com isso, todos tentam observar o esporte como competição apenas entre atletas, mas cada vez mais os departamentos financeiros das equipes tem papel decisivo nos campeonatos. As ferramentas estatísticas podem ser de grande valia para tentar elucidar este dilema. Esta investigação busca atender este objetivo através de técnicas associadas com valores outliers. Os valores outliers são elementos usualmente incomuns ao conjunto de dados, valores excessivamente extremos quanto a ordem de grandeza das variáveis em estudo. Os procedimentos de detecção de valores outliers já são bastante difundidos, mas os estudos para valores outliers multivariados ainda não são plenamente estabelecidos. Técnicas inovadoras para este propósito são apresentadas na literatura, em particular, a metodologia Data-driven Cluster Analysis Method (DDCAM). Este estudo utiliza a metodologia para investigar a forte associação entre desempenho financeiro e resultado desportivo em clubes do futebol brasileiro de alta performance.
Assessment of the effect of changes in consolidation conditions in the advance of the carbonation front in cementitious matrix composites.
(2021) Silva, Ruan Gustavo Rezende; Magalhães, Aldo Giuntini de; Campos, Christopher Augusto; Silva, Ivair Ramos
Carbonation is one of the main deleterious effects of reinforced concrete structures, as it creates a favorable condition for the reinforcement depassivation and, thus, facilitates the onset of the corrosive process. The phenomenon is directly influenced by the material void’s structure, which is affected by the consolidation of the mass in the fresh state, subject evaluated in this study. For this purpose, samples were made using two water to cement ratios and defining two different consolidation methods. Compressive strength tests were carried out for the mechanical characterization of the specimens, in addition to accelerated carbonation tests, monitoring the progress of the carbonated thickness using the phenolphthalein colorimetric indicator, during 98 days. Microstructural differences were evaluated by scanning electron microscopy (SEM). The results indicate that the lower the workability of the mixture, the greater the impacts on the compressive strength of the material, resulting from failures in the consolidation stage. Nevertheless, another behavior is observed when evaluating this effect in the advancement of the carbonation front, indicating that the voids structure of the material should not be evaluated only according to its volume, but also in terms of the pattern of its distribution, its morphology and its connectivity.
Kronecker delta method for testing independence between two vectors in high-dimension.
(2021) Silva, Ivair Ramos; Zhuang, Yan; Silva Júnior, Júlio César Araújo da
Conventional methods for testing independence between two Gaussian vectors require sample sizes greater than the number of variables in each vector. Therefore, adjustments are needed for the high-dimensional situation, where the sample size is smaller than the number of variables in at least one of the compared vectors. It is critical to emphasize that the methods available in the literature are unable to control the Type I error probability under the nominal level. This fact is evidenced through an inten- sive simulation study presented in this paper. To cover this lack, we introduce a valid randomized test based on the Kronecker delta covariance matrices estimator. As an empirical application, based on a sample of companies listed on the stock exchange of Brazil, we test the independence between returns of stocks of different sectors in the COVID-19 pandemic context.
Exact sequential test for clinical trials and post-market drug and vaccine safety surveillance with Poisson and binary data.
(2021) Silva, Ivair Ramos; Maro, Judith; Kulldorff, Martin
In sequential analysis, hypothesis testing is performed repeatedly in a prospective manner as data accrue over time to quickly arrive at an accurate conclusion or decision. In this tutorial paper, detailed explanations are given for both designing and operating sequential testing. We describe the calculation of exact thresholds for stopping or signaling, statistical power, expected time to signal, and expected sample sizes for sequential analysis with Poisson and binary type data. The calculations are run using the package Sequential, constructed in R language. Real data examples are inspired on clinical trials practice, such as the current efforts to develop treatments to face the COVID-19 pandemic, and the comparison of treatments of osteoporosis. In addition, we mimic the monitoring of adverse events following influenza vaccination and Pediarix vaccination.
Numerical versus asymptotic sequential interval estimation of population sizes.
(2021) Silva, Ivair Ramos; Bhattacharjee, Debanjan; Mukhopadhyay, Nitis
The challenge of estimating a population size (N) is usually faced with the well-established mark-recapture sampling scheme. The basic idea is to tag t items of the population and then observe the number of tagged items appearing in a subsequent random sample. The frequencies of tagged versus non-tagged items are informative to estimate N. For construction of fixed-width and fixed-accuracy confidence intervals for N, this paper compares a numerical non-replacement-sampling sequential design against an asymptotic replacement-sampling sequential design. While the former has shown to perform better in terms of expected sample size, the latter was found superior in terms of robustness with respect to the magnitude of N.
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.
Work hours as a risk factor for SARS-CoV-2 infections : cardiometabolic and sleep characteristics in rotating shift workers.
(2022) Nascimento, Raiza Aranha; Fajardo, Virgínia Capistrano; Menezes Júnior, Luiz Antônio Alves de; Mendonça, Pedro Henrique Marques; Nascimento, Maria Cristina Veiga Aranha; Tristão, Pedro Marques Oliveira; Oliveira, Fernando Luiz Pereira de; Nascimento Neto, Raimundo Marques do
This study aims to describe the health characteristics of rotating shift mining workers that may be related to a worse course scenario for COVID-19, according to literature data. Methods: Is a cross-sectional from three studies with 1478 shift workers. Social, demographic, clinical, and biochemical variables were analyzed. Risk factors for COVID-19 analyzed: hyperglycemia, altered blood pressure, dyslipidemia, hypovitaminosis D, obesity, presence of pre-existing cardiovascular diseases, and smokers. Results: Evaluating the grouped risk factors for an unfavorable evolution of COVID-19 most workers (91.0%) presented at least one risk factor. Discussion: With coronavirus in pandemic circulation, we noticed that mineworkers are in a vulnerable position. Their exposure to occupational risk factors, to the shift system, which directly affects sleep and negatively influences immunity, added to the conditions of favorable transmissibility by the flow of people from the mines leads us to believe in their greater susceptibility to acquiring the most serious forms of the disease.
Influência do Programa Bolsa Família no índice antropométrico peso para idade das crianças beneficiárias em uma cidade no interior de Minas Gerais.
(2021) Santos, Mariana Cristina Silva; Bearzoti, Eduardo; Marliére, Cláudia Aparecida; Bonolo, Palmira de Fátima
Objetivo: avaliar a influência do Programa Bolsa Família (PBF) no perfil nutricional de crianças beneficiárias, no município de Ouro Preto, MG, Brasil, por meio do índice antropométrico peso para idade (P/I). Métodos: Estudo epidemiológico analítico, realizado a partir de registros contidos no Sistema de Vigilância Alimentar e Nutricional (SISVAN) e no Cadastro Único do Governo Federal (CadÚnico), referentes a crianças com até 84 meses; e os efeitos das variáveis foram estimados por meio do Modelo Linear de Efeito Misto. Resultados: observou-se P/I elevado de 15,4% na primeira avaliação e de 8,3% na segunda; sendo que a redução média foi significativa, de 0,09 no valor do escore Z a cada 100 dias de exposição ao PBF. Conclusão: o tempo de permanência no PBF pode contribuir de maneira significante no estado nutricional das crianças.
Monte Carlo test for stochastic trend in linear structural models for the location-scale family.
(2021) Silva, Ivair Ramos; Ernesto, Dulcidia Carlos Guezimane; Oliveira, Fernando Luiz Pereira de; Marques, Reinaldo Antônio Gomes; Oliveira, Anderson Castro Soares de
In linear structural models for time series, a key point is the decision between modeling the trend of non-stationary processes through a deterministic or a stochastic term. The present paper introduces a Monte Carlo hypothesis test procedure to guide in such a decision. The method works for any time series distribution belonging to the location-scale family, where the analytical shape of the distribution must be defined by the user prior to apply the method. The proposed method provides an alpha-level test for any time series of length greater than 3 and it does not demand assumptions on the distribution of the trend term when it is actually stochastic.
Confidence intervals for spatial scan statistic.
(2021) Silva, Ivair Ramos; Duczmal, Luiz Henrique; Kulldorff, Martin
The spatial scan statistic is a popular statistical tool to detect geographical clusters of diseases. The basic problem of constructing confidence intervals for the relative risk of the most likely cluster has remained an open question. To cover this lack, a Monte Carlo based interval estimator for the relative risk of the primary cluster is derived. The method works for the circular spatial scan statistic applied to binomial data, and it ensures, by construction, an analytical control of the coverage probability under the nominal confidence coefficient. In addition, its performance is illustrated on simulated and real data of birth defects in New York State.
Optimal alpha spending for sequential analysis with binomial data.
(2020) Silva, Ivair Ramos; Kulldorff, Martin; Yih, W. Katherine
For sequential analysis hypothesis testing, various alpha spending functions have been proposed. Given a prespecified overall alpha level and power, we derive the optimal alpha spending function that minimizes the expected time to signal for continuous as well as group sequential analysis. If there is also a restriction on the maximum sample size or on the expected sample size, we do the same. Alternatively, for fixed overall alpha, power and expected time to signal, we derive the optimal alpha spending function that minimizes the expected sample size. The method constructs alpha spending functions that are uniformly better than any other method, such as the classical Wald, Pocock or O’Brien–Fleming methods.The results are based on exact calculations using linear programming. All numerical examples were run by using the R Sequential package.

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