Avaliação de Métodos de Mineração de Textos Aplicados à Detecção de Fake News Eleitorais Brasileiras

The evolution of the media has contributed to the spread of false news, especially after the emergence of digital social networks. The speed with which this news spread made it impossible to manually check this huge amount of data. In this context, work in several areas has been carried out in order to try to minimize the damage caused by the proliferation of socalled fake news. The objective of this work is to evaluate the effectiveness of the most used methods to check correspondence of texts, in the context of detecting false news, based on the Brazilian presidential elections of 2018, as well as making a comparison with the results of the US election. 2016, published in the literature. Additionally, an overview of the fake news by followers of each candidate is presented. A controlled experiment was planned and executed to compare the effectiveness of the selected methods. The TF-IDF and BM25 methods stood out in this context, having, statistically and respectively, similar averages of Accuracy (79,86% and 79,00%), Precision (79,97% and 78,76%), Sensitivity (78,97% and 76,05%) and Measure-F1 (79,47% and 77,38%). The effectiveness was similar to that of the North American context, in which the BM25 achieved an Accuracy of 79,99%. Furthermore, considering the universe of checked news available, the analyzed period and a margin of error of 3,5%, it was evident that fake news were disclosed by both sides and that followers of the candidate Jair Bolsonaro (PSL) were responsible for 62,25% of tweets related to fake news, against 37,75% of followers of candidate Fernando Haddad (PT). With regard to accounts deleted from the social network in a short time, 59,96% were followers of the PSL candidate and 40,04% of followers of the PT candidate. The dissemination of fake news does not always imply intention, and may only imply greater engagement by some followers.Contexto: A evolução dos meios de comunicação tem contribuído com a disseminação de notícias falsas, principalmente após o surgimento das redes sociais digitais. A velocidade com que estas notícias se espalham tornaram inviável a checagem manual desse imenso volume de dados. Diante deste contexto, trabalhos em diversas áreas têm sido realizados a fim de tentar minimizar os danos causados pela proliferação das denominadas fake news. Objetivo: O objetivo deste trabalho é avaliar a eficácia dos métodos mais utilizados para verificar correspondência de textos, no contexto da detecção de notícias falsas, tendo como base as eleições presidenciais brasileiras de 2018, bem como fazendo um comparativo com os resultados da eleição norte-americana de 2016, publicados na literatura. Adicionalmente, uma visão geral das fakes por seguidores de cada candidato é apresentada. Método: Foi planejado e executado um experimento controlado, para comparar a eficácia dos métodos selecionados. Resultados: Os métodos TF-IDF e BM25 se destacaram nesse contexto, possuindo, estatisticamente e respectivamente, médias similares de Acurácia (79,86% e 79,00%), Precisão (79,97% e 78,76%), Sensibilidade (78,97% e 76,05%) e Medida-F1 (79,47% e 77,38%). Conclusão: A eficácia foi similar à do contexto norte-americano, no qual o BM25 alcançou uma Acurácia de 79,99%. Além disso, considerando o universo de notícias checadas disponível, o período analisado e uma margem de erro de 3,5%, evidenciou-se que houve divulgação de fakes por ambos os lados e que seguidores do candidato Jair Bolsonaro (PSL) foram responsáveis por 62,25% dos tweets relacionados a notícias falsas, contra 37,75% dos seguidores do candidato Fernando Haddad (PT). No que diz respeito às contas excluídas da rede social em um curto espaço de tempo, 59,96% eram de seguidores do candidato do PSL e 40,04% de seguidores do candidato do PT. A divulgação de fake news nem sempre implica intenção, podendo implicar apenas um engajamento maior por parte de alguns seguidores

Biofortificação agronômica de grãos de feijão com zinco

The objective of this work was to evaluate the effects of the split and combinated application of foliar zinc (ZnF) + soil Zn (ZnS) on Zn concentration in the grains (ZnCG) of common bean (Phaseolus vulgaris). Two experiments were carried out in a greenhouse during two seasons. In the first experiment, two common bean cultivars received six ZnF rates (0, 120, 240, 480, 720, or 1,200 g ha-1), with split applications at the R5, R7, and R8, or R7 and R8, or R8 plant stages. In the second experiment, one cultivar received three ZnS rates (0, 5, or 10 kg ha-1) combined with ZnF rates (0, 1, 1.5, 3, 6, or 10 kg ha-1). In the first experiment, with the ZnF increment, ZnCG increased linearly from 15.3 to 20.7 mg kg-1. ZnF splitting did not affect ZnCG. In the second experiment, ZnF without ZnS did not affect ZnCG. ZnS doubled ZnCG in comparison with the treatment without ZnS application. At 5 kg ha-1 ZnS, the highest ZnCG (67.5 mg kg-1) was obtained with 7.8 kg ha-1 ZnF. At 10 kg ha-1, the highest ZnCG (66 mg kg-1) was obtained with 4.9 kg ha-1 ZnF. ZnF splitting is not advantageous over a single application, and the combination of ZnF and ZnS increases ZnCG in common bean, in greenhouse conditions.O objetivo deste trabalho foi avaliar os efeitos da aplicação parcelada e combinada de zinco foliar (ZnF) + Zn no solo (ZnS) sobre o teor de Zn dos grãos (TZnG) do feijão-comum (Phaseolus vulgaris). Dois experimentos foram realizados em casa de vegetação durante dois períodos. No primeiro experimento, duas cultivares de feijão-comum receberam seis doses de ZnF (0, 120, 240, 480, 720, ou 1.200 g ha-1), com aplicações parceladas nos estágios da planta R5, R7 e R8, ou R7 e R8, ou R8. No segundo experimento, uma cultivar recebeu três doses de ZnS (0, 5 ou 10 kg ha-1) combinadas com doses de ZnF (0, 1, 1,5, 3, 6 ou 10 kg ha-1). No primeiro experimento, com o incremento do ZnF, o TZnG aumentou linearmente de 15,3 para 20,7 mg kg-1. O parcelamento do ZnF não afetou o TZnG. No segundo experimento, o ZnF sem o ZnS não afetou o TZnG. O ZnS dobrou o TZnG em comparação ao tratamento sem aplicação de ZnS. Com 5 kg ha-1 de ZnS, o mais alto TZnG (67,5 mg kg-1) foi obtido com 7,8 kg ha-1 de ZnF. Com 10 kg ha-1, o mais alto TZnG (66,0 mg kg-1) foi obtido com 4,9 kg ha-1 de ZnF. O parcelamento do ZnF não é vantajoso em relação à aplicação única, e a combinação ZnF e ZnS aumenta o TZnG do feijão-comum em casa de vegetação

Text mining analysis to understand the impact of online news on public health response: case of syphilis epidemic in Brazil

BackgroundTo effectively combat the rising incidence of syphilis, the Brazilian Ministry of Health (MoH) created a National Rapid Response to Syphilis with actions aimed at bolstering epidemiological surveillance of acquired, congenital syphilis, and syphilis during pregnancy complemented with communication activities to raise population awareness and to increase uptake of testing that targeted mass media outlets from November 2018 to March 2019 throughout Brazil, and mainly areas with high rates of syphilis. This study analyzes the volume and quality of online news content on syphilis in Brazil between 2015 and 2019 and examines its effect on testing.MethodsThe collection and processing of online news were automated by means of a proprietary digital health ecosystem established for the study. We applied text data mining techniques to online news to extract patterns from categories of text. The presence and combination of such categories in collected texts determined the quality of news that were analyzed to classify them as high-, medium-and low-quality news. We examined the correlation between the quality of news and the volume of syphilis testing using Spearman’s Rank Correlation Coefficient.Results1,049 web pages were collected using a Google Search API, of which 630 were categorized as earned media. We observed a steady increase in the number of news on syphilis in 2015 (n = 18), 2016 (n = 26), and 2017 (n = 42), with a substantial rise in the number of news in 2018 (n = 107) and 2019 (n = 437), although the relative proportion of high-quality news remained consistently high (77.6 and 70.5% respectively) and in line with similar years. We found a correlation between news quality and syphilis testing performed in primary health care with an increase of 82.32, 78.13, and 73.20%, respectively, in the three types of treponemal tests used to confirm an infection.ConclusionEffective communication strategies that lead to dissemination of high quality of information are important to increase uptake of public health policy actions

MECANISMOS FISIOLÓGICOS E FISIOPATOLÓGICOS DETERMINANTES DA ATIVIDADE VASOMOTORA SIMPÁTICA

The sympathetic vasomotor activity is one of determinants of blood pressure (BP). Understanding the mechanisms involved in the control of the cardiovascular system is important in physiological and pathophysiological condition. The principal sympathetic premotor brain nuclei are confined in the paraventricular nucleus of hypothalamus (PVN) and in the rostralventrolateral medulla (RVLM). In different patophysiological condition, there is an increase in the sympathetic vasomotor tone, in part due to an increase in the activity of the PVN and RVLM neurons. In this brief review, we discussed the major mechanisms of sympathetic activation in different experimental models: 1) renovascular hypertension, 2) renoprival hypertension, 3) cardiac failure, 4) hypertension induced by nitric oxide blockade, 5) obesity and 6) gender differences. The actions of different mediators in the PVN and in the RVLM acting in long term, can change the level of sympathetic nerve activity and blood pressure and therefore, contributing for the progression of cardiovascular disease.A atividade vasomotora simpática é um dos determinantes da pressão arterial (PA). Estabelecer quais são os mecanismos geradores dessa atividade é importante para o entendimento de como o sistema cardiovascular opera, tanto em situações fisiológicas como fisiopatológicas. Os principais grupos pré-motores do simpático estão confinados no núcleo paraventricular do hipotálamo (PVN) e região rostoventrolateral bulbar (RVLM). Em diversas situações fisiopatológicas há aumento na atividade vasomotora simpática, em parte conseqüente a maior atividade dos neurônios do PVN e RVLM. Nesta breve revisão, foram discutidos os principais mecanismos de ativação simpática em diferentes modelos experimentais: 1) hipertensão renovascular, 2) hipertensão por baixa massa renal, 3) insuficiência cardíaca, 4) hipertensão por bloqueio do óxido nítrico, 5) obesidade e 6) dimorfismo sexual. As ações de diferentes mediadores sobre o PVN e RVLM podem em longo prazo determinar novos patamares de atividade simpática, modificando os níveis tensionais e dessa forma, contribuir para a progressão da doença cardiovascular

Clio’s (mis)adventures with Hermes, Hestia, and Hephaestus

This article shall reflect on how emerging technologies and the so-called “spatial turn” impact the historian’s craft. Looking at the past, the authors identify historical antecedents of both tendencies in the second generation of the Annales School. Eyeing the present and the future, the authors advance the concept of “border space” as an analytical tool to illuminate characteristics and trends in the digitized production of knowledge about the past. The article argues that some of the key values that characterize this border space – open-source scholarship, horizontal collaboration, and the free circulation of knowledge – can stimulate more democratic methods of producing historical scholarship. Keywords Digital humanities, digital history, Annales School, historiographical cultureEl artículo presenta una reflexión sobre el impacto de las nuevas tecnologías y el llamado “giro espacial” en el oficio del historiador. Con un enfoque en el pasado, el artículo busca en la segunda generación de la Escuela de Annales los antecedentes históricos de estas tendencias. Con un foco en el presente y el futuro, y tratando de realizar algunos ejercicios de diagnóstico y pronóstico, los autores proponen el concepto de “lugar de frontera” como un marco analítico capaz de iluminar algunas de las características y quizás algunas de las tendencias en la producción de conocimiento sobre el pasado. El artículo sostiene que algunos de los valores clave que caracterizan este espacio fronterizo, como la investigación de código abierto, la colaboración horizontal y la libre circulación del conocimiento, pueden estimular métodos más democráticos para la producción de investigaciones históricas. Palabras clave Humanidades digitales, historia digital, Escuela de Annales, cultura historiográfic

EMPRESA VERSUS INOVAÇÃO: UMA CONTEXTUALIZAÇÃO DO CENÁRIO BRASILEIRO

O artigo buscou descrever o Sistema Nacional de Inovação (SNI) pela atuação de seus agentes, buscando nos dados e indicadores disponíveis caracterizar as tendências e mostrar os desafios a serem vencidos. Verificou-se que o sistema de inovação é imaturo, onde a universidade assume posição central na pesquisa e desenvolvimento e a empresa assume uma posição passiva, o que a torna frágil em termos competitividade. Apesar dos incentivos em atividades de P&D serem equiparáveis aos de países desenvolvidos, existe no país uma séries de obstáculos estruturais que ocorrem no ambiente econômico brasileiro

Spreading Effect of tDCS in Individuals with Attention-Deficit/Hyperactivity Disorder as Shown by Functional Cortical Networks: A Randomized, Double-Blind, Sham-Controlled Trial

Background: Transcranial direct current stimulation (tDCS) is known to modulate spontaneous neural network excitability. The cognitive improvement observed in previous trials raises the potential of this technique as a possible therapeutic tool for use in attention-deficit/hyperactivity disorder (ADHD) population. However, to explore the potential of this technique as a treatment approach, the functional parameters of brain connectivity and the extent of its effects need to be more fully investigated. Objective: The aim of this study was to investigate a functional cortical network (FCN) model based on electroencephalographic activity for studying the dynamic patterns of brain connectivity modulated by tDCS and the distribution of its effects in individuals with ADHD. Methods: Sixty ADHD patients participated in a parallel, randomized, double-blind, sham-controlled trial. Individuals underwent a single session of sham or anodal tDCS at 1 mA of current intensity over the left dorsolateral prefrontal cortex for 20 min. The acute effects of stimulation on brain connectivity were assessed using the FCN model based on electroencephalography activity. Results: Comparing the weighted node degree within groups prior to and following the intervention, a statistically significant difference was found in the electrodes located on the target and correlated areas in the active group (p < 0.05), while no statistically significant results were found in the sham group (p ≥ 0.05; paired-sample Wilcoxon signed-rank test). Conclusion: Anodal tDCS increased functional brain connectivity in individuals with ADHD compared to data recorded in the baseline resting state. In addition, although some studies have suggested that the effects of tDCS are selective, the present findings show that its modulatory activity spreads. Further studies need to be performed to investigate the dynamic patterns and physiological mechanisms underlying the modulatory effects of tDCS. Trial Registration ClinicalTrials.gov NCT01968512