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Paulownin triazole-chloroquinoline derivative : a promising antiviral candidate against chikungunya virus.
No full textViral infections, including arboviruses such as chikungunya, zika, dengue, and mayaro fever, remain significant global health and economic challenges, fueled by the emergence and resurgence of mosquito-borne diseases. Natural products, especially plant-derived compounds, have been crucial in drug discovery and often serve as scaffolds for synthetic drug development. This study focused on modifying paulownin, an isolated lignan, through a Click reaction to incorporate 1,2,3-triazole and quinolinic ring frameworks. The resulting derivative 7 was evaluated for its in vitro antiviral activity against Alphavirus chikungunya (CHIKV). The paulownin derivative 7 did not exhibit cytotoxicity in Vero cells and demonstrated potent activity against CHIKV, with median effective concentration value of 9.05 μM and a selectivity index exceeding 16.8. Furthermore, compound 7 outperformed positive controls, being over 46 times more active against CHIKV. Cytopathic effect assays confirmed this anti-CHIKV activity. The virucidal assay indicated that the compound does not exert a direct effect on CHIKV particles before cell infection. RT-qPCR studies further demonstrated derivative 7 significantly reduces CHIKV replication. These findings highlight the paulownin derivative 7 as a promising and selective candidate for CHIKV treatment
A voz como instrumento pedagógico : os impactos da saúde vocal na profissão docente.
No full textPrograma de Pós-Graduação em Educação. Departamento de Educação, Instituto de Ciências Humanas Sociais, Universidade Federal de Ouro Preto.A voz é uma ferramenta essencial para a comunicação e interação em sala de aula, sendo fundamental para o processo de ensino-aprendizagem. No entanto, devido a diversos fatores internos e externos, os professores enfrentam uma alta prevalência de problemas vocais. Essas alterações podem causar prejuízos tanto para o professor, em termos de qualidade de vida e afastamento do trabalho, quanto para os alunos, interferindo na compreensão e no aprendizado. Nesse sentido, o presente trabalho tem como objetivo apresentar os principais motivos encontrados na literatura relacionados à promoção de alterações vocais que afetam os professores, bem como o impacto dessas alterações na saúde e no desempenho desses profissionais. O método utilizado foi a revisão integrativa da literatura. Os principais resultados encontrados confirmaram que os professores são os profissionais vocais com mais ocorrências de distúrbios vocais, e que tais distúrbios levam ao absenteísmo com um número maior do que quando comparado a outros profissionais. Dentro dos grupos de risco identificou-se que mulheres têm maiores probabilidades de risco vocal do que os homens, e quanto mais avançada a idade essa probabilidade cresce. Os professores do ensino primário têm mais riscos do que em outros níveis de ensino, e algumas disciplinas podem influenciar para a contribuição de um distúrbio vocal. Os fatores de risco encontrados foram multidimensionais, incluindo fatores ambientais e fatores individuais ou psicossociais sendo respectivamente os primeiros: ambientes acústicos desfavoráveis, ruídos, alta demanda de uso da voz, número de alunos na sala de aula, poeira, pó de giz, ar condicionado, temperatura, pouco descanso vocal, entre outros. E os individuais: estresse, ansiedade, alergias, resfriados, infecções sinusais e demais influências inflamatórias, problemas físicos, tabagismo, problemas gastroesofágicos, má hidratação, excesso de cafeína, má postura, saúde em geral, hábitos de vida, falta de habilidades vocais, entre outros. Também foram encontradas estratégias de prevenção divididas em três categorias: higiene, educação e treinamento vocal. Portanto, conclui-se que é necessário investir em pesquisas e políticas públicas que promovam a prevenção e o cuidado vocal adequado, visando melhorar a saúde vocal dos professores, o que resultará em uma melhor qualidade de ensino.The voice is an essential tool for communication and interaction in the classroom, being fundamental to the teaching–learning process. However, due to several internal and external factors, teachers face a high prevalence of vocal problems. These alterations can cause harm both to teachers, in terms of quality of life and work absenteeism, and to students, by interfering with comprehension and learning. In this sense, the present study aims to present the main reasons found in the literature related to the promotion of vocal alterations that affect teachers, as well as the impact of these alterations on the health and performance of these professionals. The method used was an integrative literature review. The main results found confirmed that teachers are the vocal professionals with the highest occurrence of vocal disorders, and that such disorders lead to absenteeism at a higher rate when compared to other professionals. Among the identified risk groups, women were found to have a higher probability of vocal risk than men, and this probability increases with advancing age. Primary school teachers present greater risks than those at other educational levels, and certain subjects may contribute to the development of vocal disorders. The risk factors identified were multidimensional, including environmental factors and individual or psychosocial factors. The environmental factors included unfavorable acoustic environments, noise, high vocal demand, number of students in the classroom, dust, chalk dust, air conditioning, temperature, insufficient vocal rest, among others. Individual factors included stress, anxiety, allergies, colds, sinus infections and other inflammatory influences, physical problems, smoking, gastroesophageal disorders, poor hydration, excessive caffeine intake, poor posture, general health, lifestyle habits, lack of vocal skills, among others. Preventive strategies were also identified and divided into three categories: hygiene, education, and vocal training. Therefore, it is concluded that it is necessary to invest in research and public policies that promote prevention and adequate vocal care, aiming to improve teachers’ vocal health, which will result in better quality of teaching
Cardiac and electrodermal responses to threats : modulation by childhood sexual abuse history.
No full textBackground: Childhood sexual abuse (CSA) is associated with significant negative lifelong consequences for physical and mental health. However, the impact of CSA history on danger perception and response has been understudied. In this study, we explored how autonomic reactivity to threats is influenced by the history of CSA in a nonclinical sample. Methods: Participants were undergraduate students with no current diagnosis of cardiovascular disease or mental disorders. After exclusion criteria were applied, the sample consisted of 135 participants. Among these 135 participants, 48 (mean age, 20.43 years; SD, 3.07; 9 men) reported having experienced significant CSA (CSA group), and 87 (mean age, 20.89 years; SD, 4.99; 30 men) reported not having had such experiences (non-CSA group). The participants viewed trauma-unrelated threatening or neutral pictures while their skin conductance response and heart rate data were collected. Results: Compared with the neutral pictures, when viewing trauma-unrelated threatening pictures, the non-CSA group presented bradycardia, which is a typical cardiac response upon exposure to negative images. In contrast, the CSA group presented a blunted cardiac response. Furthermore, we observed an overrepresentation of skin conductance nonresponders in the CSA group. Conclusions: Taken together, these findings suggest that youth who are exposed to CSA seem to have blunted autonomic responsiveness to threats. This blunted responsiveness is an atypical pattern that may represent a biomarker of many unfavorable physiological and psychological outcomes
Controle e otimização de sistemas de saneamento urbano : aplicação de máquinas de estados finitos e controle preditivo.
No full textPrograma de Pós-Graduação em Instrumentação, Controle e Automação de Processos de Mineração. Departamento de Engenharia de Controle e Automação, Escola de Minas, Universidade Federal de Ouro Preto.A gestão eficiente de sistemas de esgoto e estações de tratamento de águas residuais é essencial para minimizar impactos ambientais e otimizar processos de saneamento. Esta dissertação pro- põe duas estratégias de controle aplicadas a sistemas hídricos urbanos, visando reduzir trans- bordamentos, aumentar a eficiência das estações em termos de qualidade do efluente e custo operacional, e reduzir emissões de gases de efeito estufa. A primeira estratégia utiliza uma Máquina de Estados Finitos para controlar o nível de tanques de armazenamento integrados a redes de esgoto. Implementada em MATLAB/Simulink e otimizada via algoritmo de Simula- ted Annealing, foi avaliada em três cenários pluviométricos distintos. Os resultados indicam redução significativa no volume total de transbordo, destacando-se uma diminuição de 56% no terceiro cenário. A segunda estratégia aplica controle preditivo não linear para aumentar a efici- ência de uma estação de tratamento, mitigando emissões de gases de efeito estufa. Comparado com controles proporcionais-integral convencionais em simulações que consideram a geração de gases, o controlador preditivo não linear mostrou operação mais sustentável e eficiente. Am- bas as estratégias demonstram capacidade de aprimorar o controle de sistemas de saneamento, reduzindo impactos ambientais e melhorando a eficiência operacional.Efficient management of sewer systems and wastewater treatment plants is essential to min- imize environmental impacts and optimize sanitation processes. This dissertation proposes two control strategies applied to urban water systems, aiming to reduce overflows, increase the efficiency of treatment plants in terms of effluent quality and operational cost, and reduce greenhouse gas emissions. The first strategy employs a Finite State Machine to control the level of storage tanks integrated into sewer networks. Implemented in MATLAB/Simulink and optimized using a Simulated Annealing algorithm, it was evaluated under three distinct rain- fall scenarios. The results indicate a significant reduction in total overflow volume, with a notable 56% decrease in the third scenario. The second strategy applies nonlinear predictive control to enhance the efficiency of a treatment plant while mitigating greenhouse gas emis- sions. Compared to conventional proportional-integral controls in simulations that account for gas generation, the nonlinear predictive controller demonstrated a more sustainable and effi- cient operation. Both strategies show the potential to improve the control of sanitation systems, reducing environmental impacts and enhancing operational efficiency
Domestic dogs exposed to orthopoxvirus in urban areas of Brazil.
No full textDomestic animals can share viral pathogens with humans, acting mainly as a bridge host. The Orthopoxvirus genus hosts important zoonotic species that have emerged in urban areas worldwide. Nevertheless, the role of companion animals, such as dogs and cats, in the circulation of orthopoxviruses in urban areas remains poorly understood. Therefore, the objective of this study was to evaluate the presence of neutralizing anti-orthopoxvirus antibodies in serum samples from owned dogs from three municipalities in Minas Gerais, as well as the presence of the C11R and A56R orthopoxviruses genes. The presence of neutralizing antibodies was detected in 14.3% of the animals investigated. However, no sample was positive for the presence of the genes investigated. Further study of the population of dogs in urban areas may prove a valuable tool for understanding the spread of orthopoxviruses in urbanized areas of Brazil
Detecção de intrusões em redes de dispositivos IOT por aprendizado federado.
No full textPrograma de Pós-Graduação em Ciência da Computação. Departamento de Ciência da Computação, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto.A pesquisa investiga o uso de técnicas de Aprendizagem Federada para melhorar a detecção de intrusões em redes de IoT, com foco nos algoritmos FedAvg, FedProx e FedAdam, para treinamento colaborativo de modelos. O objetivo é comparar o desempenho e a eficácia dos algoritmos na detecção de intrusões em redes de dispositivos Io. O estudo visa atender aos objetivos delineados e a fornecer uma análise abrangente do desempenho e da eficácia dos métodos. Propõe-se que sejam utilizados vários modelos de aprendizado de máquina, técnicas de pré-processamento de dados, ferramentas e bibliotecas para avaliar o desempenho da detecção de intrusões em redes IoT. Os resultados da pesquisa demonstraram, através da comparação, a eficácia das técnicas de Aprendizagem Federada na melhoria da precisão da detecção de intrusões em redes de dispositivos IoT. A análise demonstrou que o desempenho dos algoritmos FedAvg, FedProx e FedAdam é sensível a variações no desequilíbrio de classes, na heterogeneidade dos dados e na complexidade da classificação. O FedProx apresentou superioridade consistente em relação ao FedAvg nas métricas de acurácia e pontuação F1. Vantagem atribuída por seu termo de regularização proximal, que se mostrou eficaz em estabilizar o processo de treinamento em cenários de dados não-IID (não independentes e identicamente distribuídos), característicos de ambientes IoT do mundo real. Finalmente, o estudo destaca a importância de um conjunto de dados que referencia ataques em larga escala no ambiente IoT.The research investigates the use of Federated Learning techniques to improve intru- sion detection in IoT (Internet of Things) networks, focusing on the FedAvg, Fed- Prox and FedAdam algorithms for collaborative model training. The objective is to compare the performance and effectiveness of the algorithms in detecting intrusions in networks of IoT devices. The study aims to meet the outlined objectives and pro- vide a comprehensive analysis of the performance and effectiveness of the methods. It is proposed that several machine learning models, data preprocessing techniques, tools and libraries be used to evaluate the performance of intrusion detection in IoT networks. The research results demonstrated, through comparison, the effectiveness of Federated Learning techniques in improving the accuracy of intrusion detection in IoT device networks. The analysis demonstrated that the performance of the FedAvg, FedProx and FedAdam algorithms is sensitive to variations in class imba- lance, data heterogeneity and classification complexity. FedProx showed consistent superiority over FedAvg in the accuracy and F1 score metrics. This advantage is attributed to its proximal regularization term, which has proven effective in stabili- zing the training process in non-IID (non-independent and identically distributed) data scenarios, which are characteristic of real-world IoT environments. Finally, the study highlights the importance of a dataset that references large-scale attacks in the IoT environment
O testemunho do sobrevivente contra a máquina de produzir moribundos do Brasil : historiografia como estratégia para uma desatualização da tortura.
No full textPrograma de Pós-Graduação em História. Departamento de História, Instituto de Ciências Humanas e Sociais, Universidade Federal de Ouro Preto.O filósofo Walter Benjamin apresentou uma figuração do Anjo da História em que o ser celestial aparecia com as costas voltadas para o futuro, para onde era empurrado com a força de um vendaval chamado “progresso”. À sua frente, contemplava o passado, que se acumulava como um monte de ruínas resultantes da barbárie e da catástrofe. Apesar de estar acima deste cenário, desejava descer dos céus para acordar os mortos desta terra. E desejava, também, ao que parece, olhar o que havia entre os destroços, já que mantinha os olhos esbugalhados, ainda que diante de um forte vento e da natural poeira que resta das demolições. Parece, também, querer escavar os escombros, escovar a história a contrapelo, pois espera encontrar justamente em meio a destruição a centelha da esperança, um anel que tenha sobrevivido como o fragmento de um tesouro e que possa ser transmitido de uma geração para a outra. Esta tese é um convite a realizarmos o que o Anjo da História, cujas asas se enrodilharam pelo vendaval, não conseguiu fazer: parar e olhar os escombros. É um convite para sermos seres ruminantes, não como as vacas que só vivem no presente, como por Friedrich Nietzsche na Segunda Consideração Intempestiva, mas como historiadores que se demoram no presente, em uma cena, em um ponto focal, para analisar uma problema. Este trabalho analisa testemunhos sobre a tortura no Brasil contemporâneo, com o intuito de identificar as táticas e estratégias de sobrevivência, jogar luz sobre a ética das comunidades formadas a partir destas histórias, perceber os elementos que restam por ser simbolizados aquém das narrações. A primeira hipótese é de que há, em operação no Brasil, uma “máquina de produzir moribundos” relacionada à permanência da prática da tortura que, dentre outras formas de atuação, atua no aprisionamento simbólico das testemunhas no lugar do passado de torturados. Por conseguinte, a segunda hipótese é a de que o campo da história é importante nas ações de emperramento da máquina na medida em que possibilita a elaboração temporal das vivências e promove uma requalificação simbólica dos relatos em que os sobreviventes passam de vítimas à testemunhas. A historiografia é entendida como uma estratégia de emperramento da máquina de produzir moribundos, não somente por denunciar a sua existência e por atuar na transposição das vítimas de sobreviventes para testemunhas, mas por jogar luz à comunidade formada no entorno destas testemunhas e por propor e praticar, neste próprio ato de acolhimento dos relatos, valores sociais fundados na democracia e, assim, opostos àqueles que geraram a tortura. Contribuimos, desse modo, para a desatualização da tortura através do exercício de ruminar sobre o conteúdo destes relatos, gesto que enfrenta, em seu próprio realizar, a hegemonia da historicidade atualista, e, promovendo o aumento da compreensão quanto ao horror da tortura e a “desmoribundização” das testemunhas, auxiliamos nos esforços em prol da liquidação da repetição. O testemunho, em nossa perspectiva, é mais do que um relato concedido em um determinado dia, hora e local, mas um signo profundo que estrutura a narração do indivíduo na vida que se desdobra após a sobrevivência, e um elemento existencial de temporalização em que a testemunha é o tempo.The philosopher Walter Benjamin introduced a new configuration of the Angel of History, in which the celestial being appeared with his back turned to the future, where it was pushed with the pressure of a gale called “progress”. Ahead, it contemplated the past, which drifted in ruins deriving from barbarity and catastrophe. Despite being above this scenario, it wished it could descend from heaven to wake the dead from this land. It also wished, as it seems, to gaze at the debris, since it kept its bulging eyes at it even though facing a strong wind and dust from demolition remains. It looks as if it is also craving to dig the debris, brush history against the grain, for it hopes to just find, amidst destruction, the spark of hope, a ring that survived like a treasure fragment which can be inherited by future generations. This thesis is an invitation to accomplish what the Angel of History, whose wings were curled by the gale, could not do: pause and gaze at the debris. It is an invitation to be ruminants, not as cows that live only in the present, like by Friedrick Nietzsche in The Second Untimely Meditation, but as historians who linger in the present, in a scene, in a focal point, to analyze a problem. This study analyzes testimonies about torture in contemporary Brazil pursuing to identify the survival tactics and strategies, shed light on the communities ethics framed from these stories, perceive the elements that remain for being symbolized behind the narratives. The first hypothesis is that there is an operation in Brazil called a “moribund/dying producing machine” related to the permanence of torture practice, which beyond other means of operation, acts symbolically imprisoning the witnesses in a past torture place. Therefore, the second hypothesis is that the field of history is important for stiffening actions of the machine, enabling the experiences of temporal elaboration and promoting a symbolic requalification of the narratives which the survivors go from victims to witnesses. Historiography is understood as a strategy to stiffen the moribund/dying producing machine not only for reporting its existence, but for operating switching survivor victims to witnesses. Hence, shedding light to the community framed around these witnesses, offering and practicing, in this act of receiving reports, social values founded in democracy, contrary to those who yielded torture. Thereby, we contribute to this behind the times torture through the act of ruminating about the content of these narratives. An action that, when performed, faces the hegemony of current historicity. Consequently, while promoting an understanding expansion about the horrors of torture and the “demoribundization” of witnesses, we support the efforts on behalf of ending repetition. The testimony, from our perspective, is more than a report given at a certain day, time and place, but a profound sign that structures the individual narrative that is unfolded after the victim’s survival, and an existential element of temporalization in which the witness is time
Açaí seed extract mitigates intestinal and hypothalamic alterations in obese mice.
No full textObesity is a significant health concern, significantly contributing to increased morbidity and mortality by disrupting multiple physiological systems. It is strongly associated with metabolic dysfunctions, including impaired glycemic homeostasis, compromised intestinal barrier integrity, and gut microbiota imbalances, all exacerbating the risk of chronic diseases. The hydroalcoholic extract of açaí seeds (ASE), rich in phenolic compounds, has demonstrated beneficial effects on obesity and hyperglycemia; however, its impacts on gut health and gut-hypothalamus communication remain unclear. This study aimed to investigate the therapeutic effect of ASE in intestinal and hypothalamic alterations associated with obesity and compare it with Metformin. Male C57BL/6 mice were fed a high-fat or standard diet for 14 weeks. The ASE (300 mg/kg/day) and Metformin (300 mg/kg/day) treatments started in the tenth week until the fourteenth week, totaling four weeks of treatment. Our data show that the treatment with ASE and Metformin reduced body weight, ameliorated lipid profile, hyperglycemia, and plasma hyperleptinemia, and decreased the oxidative damage in the gut by reducing immunostaining of 8-isoprostane and NOX-4 expression, and improved the intestinal parameters and hypothalamic gene expression. Obesity-induced dysbiosis in the HF group was marked by reduced Proteobacteria and elevated LPS plasma levels, which were improved by treatments with ASE and Metformin. These findings suggest that ASE and Metformin are promising strategies to counteract the adverse effects of obesity on intestinal health and gut-hypothalamus communication, though they act through distinct mechanisms. Therefore, we can suggest that ASE is a promising natural product for treating the intestinal alterations associated with obesity
Synthetic peptides derived from hypothetical proteins as potential antigens for the diagnosis of canine visceral leishmaniasis and tegumentary leishmaniasis.
No full textIn the present study, we investigated the potential use of five linear peptides as a potential antigens for the immunodiagnosis of tegumentary leishmaniasis (TL) and canine visceral leishmaniasis (CVL). We used bioinformatics approaches to identify linear B-cell epitopes in five hypothetical proteins from a Leishmania (Leishmania) infantum proteome study. To obtain the peptide sequences of each hypothetical protein, we used the GenBank and SwissProt online databases. These peptides were synthesized and tested, alone or in a cocktail, in enzyme-linked immunosorbent assays (ELISAs) against serum samples from patients with TL and from dogs infected with CVL. Our data shows that for CVL diagnosis, the best results were found with peptides 1 and 5, which showed sensitivity values of 97.30% and 94.54%, and specificity values of 93.83% (pep 1) and 91.63% (pep 5), respectively. For TL, all peptides showed higher sensitivity and specificity when compared with SLALb, with the peptide cocktail obtaining a 99.10% accuracy. This study's outcome suggests that these peptides may constitute a potential tool for a more sensitive and specific serodiagnosis of TL and CVL
Effects of plant and substrate types on turbidity removal in constructed wetlands : experimental and w-C* model validation.
No full textConstructed wetlands are nature-based technologies widely used for the treatment of wastewater and contaminated surface water. This study evaluated the efficiency of free wa- ter surface (FWS) and horizontal subsurface flow (HSSF) constructed wetlands in reducing the turbidity of mine spoil rainwater using the w-C* model. Different hydraulic retention times (2, 4, and 6 days) were tested, and the influence of macrophyte type and substrate on the w parameter was investigated. Model calibration was performed based on correlation coefficients (R), coefficient of determination (R2 ), Nash–Sutcliffe efficiency (NSE), and root mean square error (RMSE). The results indicated a 99% reduction in turbidity, with average values of R = 0.87 ± 0.05 (FWS) and 0.87 ± 0.03 (HSSF), and NSE of 0.76 ± 0.04 (FWS) and 0.74 ± 0.07 (HSSF), demonstrating good agreement between observed and predicted data. The settling rate (w) ranged from 0.16 to 0.40 m·d −1 in FWS and from 0.20 to 0.70 m·d −1 in HSSF, with the lowest value recorded in the control (0.09 m·d −1 ). The best performances were observed in FWS-P with Pistia stratiotes (0.40 m·d −1 ) and HSSF with Typha domingensis (0.70 m·d −1 ), demonstrating that vegetation, combined with the use of medium-grain substrate (9.5–19.0 mm), enhances turbidity removal. The w-C* model proved to be a ro- bust tool for describing the kinetics of suspended colloidal particle removal in constructed wetlands, providing valuable insights for optimizing hydraulic parameters and design criteria for full-scale application