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Model for characterization of price series based on coupled harmonic oscillators.
No full textUm modelo baseado nas equações diferenciais que descrevem a dinâmica de um sistema físico composto por dois osciladores acoplados é apresentado para caracterizar séries de preços. A partir da discretização de tais equações, encontramos um modelo vetorial autorregressivo (VAR) de segunda ordem. Avaliamos o modelo nas séries de fechamento diários de duas ações relevantes do índice Ibovespa. A estacionariedade de tais séries foi averiguada pelo teste de Dickey-Fuller. Graficamente, verificamos que os resíduos resultantes da aplicação das séries no modelo não apresentam nenhum tipo de padrão.A model based on differential equations that describe the dynamics of a physical system composed of two coupled oscillators is presented to characterize price series. From the discretization of such equations, we find a second-order autoregressive vector model (VAR). We evaluate the model in the daily closing series of two relevant stocks from Ibovespa index. The stationarity of such series was verified by the Dickey-Fuller test. Graphically, we verify that the residuals resulting from the application of the series in the model do not present any kind of pattern
PIBID, ProfLetras, and PRP : impacts and challenges of teacher training public policies in Language and Literature teaching.
No full textO riso cômico no pensamento de Henri Bergson.
No full textPrograma de Pós-Graduação em Filosofia. Departamento de Filosofia, Instituto de Filosofia, Arte e Cultura, Universidade Federal de Ouro Preto.O trabalho que segue tem por finalidade discutir alguns elementos acerca da comicidade
no pensamento de Henri Bergson, presente no livro O riso: ensaio sobre o significado do
cômico (1900), dos quais, e principalmente, o teor analítico do seu ensaio. Assim como
foi defendido pelo filósofo, O riso é um estudo de teor analítico, contudo, isto estaria na
contramão dos seus trabalhos, que recorrentemente são considerados estudos filosóficos
elaborados por meio de sua metodologia mais eminente, a intuição. Embora Bergson faça
defesa da análise como método próprio para o cômico, essa ideia não parece ser
corroborada por alguns comentadores. Nosso estudo procura fazer defesa desse ponto,
buscando elementos no ensaio bergsoniano e em estudos de seus intérpretes que ajudem
a sustentar nossa perspectiva. Assim, procuramos no primeiro capítulo identificar e
posicionar o estudo de Bergson na tradição filosófica que pensa a comédia e o riso,
intencionando demonstrar os pontos de originalidade do autor, mostrando aqueles outros
pontos que concordam com as ideias de outros pensadores. Concomitantemente a isso,
analisamos os elementos fundamentais da argumentação do filósofo, quais sejam, o riso
é essencialmente humano, diz Bergson (2018), é produto da inteligência em contato com
as demais inteligências, logo, falamos que o riso é sempre a consequência do pensamento
de um grupo. E, não obstante, ele é intermediário entre arte e vida, se estabelecendo entre
a estética e a moral da sociedade. Por esse motivo, não chega a se concretizar enquanto
arte autêntica. No capítulo segundo, aprofundamos a relação entre arte e moral, destaca-
se que o riso é um mecanismo de autodefesa da sociedade, este ao passo que procura punir
os excessos joga com a imaginação. Por fim, no capítulo terceiro, trabalhamos os tipos de
comicidade presentes na vida, e como ela se apresenta da simples forma até fazer-se
visível no caráter das pessoas.The following work aims to discuss some elements regarding comedy in the thought of
Henri Bergson, present in the book "Laughter: An Essay on the Meaning of the Comic"
(1900), notably the analytical nature of his essay. Just as the philosopher argued, laughter
is a study of an analytical nature; however, this would go against his other works, which
are often considered philosophical studies developed through his most eminent
methodology, intuition. Although Bergson advocates for analysis as a proper method for
the comic, this idea does not seem to be supported by some commentators. Our study
seeks to defend this point, looking for elements in Bergson's essay and in studies by his
interpreters that help support our perspective. Therefore, in the first chapter, we aim to
identify and position Bergson's study in the philosophical tradition that considers comedy
and laughter, intending to demonstrate the author's points of originality, showing those
that align with the ideas of other thinkers. Concurrently, we analyze the fundamental
elements of the philosopher's argumentation, namely, laughter is essentially human, says
Bergson (2018); it is a product of intelligence in contact with other intelligences, thus, we
argue that laughter is always the consequence of the thinking of a group. Furthermore, it
serves as an intermediary between art and life, establishing itself within the aesthetics and
morality of society. For this reason, it does not fully materialize as authentic art. In the
second chapter, we delve into the relationship between art and morality, highlighting that
laughter is a mechanism of society's self-defense, which, while seeking to punish
excesses, plays with the imagination. Finally, in the third chapter, we explore the types of
comedy present in life and how it ranges from simple forms to becoming visible in
people's characters
Resposta a danos no DNA promovidos pela exposição ao arsênio em fibroblastos humanos.
No full textPrograma de Pós-Graduação em Ciências Biológicas. Núcleo de Pesquisas em Ciências Biológicas, Pró-Reitoria de Pesquisa de Pós Graduação, Universidade Federal de Ouro Preto.O arsênio (As) inorgânico é um semimetal encontrado em níveis moderados na crosta terrestre, amplamente encontrado nas formas arsenito (As3+) ou arsenato (As5+). É um dos carcinógenos conhecidos mais antigos do mundo e classificado como classe I pela Agência Internacional de Pesquisa do Câncer (IARC). A exposição ao As induz a formação de Espécies Reativas (ERs), que são responsáveis por danos diretos às biomoléculas, modulação de vias de sinalização celular e marcadores epigenéticos. Além disso, o As promove alterações no ciclo celular, proliferação e apoptose. Evidências apontam que o arsenito é capaz de inibir vias de reparo de DNA, seja pela degradação de proteínas via proteassomo, seja pela diminuição da quantidade de expressão gênica. No entanto, o entendimento de quais danos de DNA são induzidos pela exposição ao arsenito, bem como o funcionamento do reparo de DNA e sua consequente mutagênese precisam ser melhor investigados. Neste contexto, por meio da exposição aguda (6 horas) ao arsenito de sódio em fibroblastos de pulmão humano (células MRC-5), pretendemos entender os mecanismos de respostas aos danos de DNA e modulação das vias associadas à exposição ao semimetal. Ensaio de viabilidade celular demonstrou que o arsenito é altamente citotóxico (IC50 – 20 μM), com tendência de indução de crescimento celular nas doses menores que 5 μM. Análises do ciclo celular por citometria de fluxo com marcação de Iodeto de propídio revelaram que As3+ induz bloqueio de ciclo celular seguido da indução de mecanismos de morte celular dose dependente. Ademais, o ensaio cometa alcalino e modificado, com o uso da enzima Formamido Pirimidina DNA Glicosilase (FPG), revelou que o arsenito é capaz de induzir altos índices de dano ao DNA, incluindo por oxidação, imediatamente ao final da exposição. Por fim, Análises proteômica por LC−MS/MS label-free shotgun mostram que o arsenito é capaz de modular proteínas estruturais e relacionadas com processos redox, como a tioredoxina redutase, além de, alterar processos biológicos relacionados ao reparo de DNA, na concentração de 30 μM, 12 horas após exposição. Em conjunto, estes resultados contribuem para o entendimento dos efeitos do arsenito nas diferentes doses e tempo após exposição aguda no DNA e proteínas, podendo contribuir para ampliar o conhecimento e o entendimento dos mecanismos mutagênicos e carcinogênicos induzidos pelo semimetal.Inorganic arsenic (iAs) is a metalloid found at moderate levels in the Earth's crust, widely present in the forms of arsenite (As3+) or arsenate (As5+). It is one of the oldest known carcinogens classified as a Group I by IARC. Arsenic exposure induces the formation of reactive oxygen species (ROS), which are responsible for direct damage to biomolecules, modulation of cellular signaling pathways, and epigenetic markers. Additionally, arsenic promotes alterations in the cell cycle, proliferation, and apoptosis. Evidence suggests that arsenite can inhibit DNA repair pathways, either through protein degradation via the proteasome or by decreasing gene expression. However, the understanding of which DNA damages are induced by arsenite exposure, as well as the functioning of DNA repair and subsequent mutagenesis needs further investigation. In this context, through acute exposure (6 hours) to sodium arsenite in human lung fibroblasts (MRC-5 cells), we aim to understand the mechanisms responding to DNA damage and modulation of associated pathways after arsenite exposure. Cell viability assays demonstrate that arsenite is highly cytotoxic (IC50 – 20 μM), with a tendency to induce cell growth at doses lower than 5 μM. Cell cycle analysis by flow cytometry with propidium iodide labeling revealed that As3+ induces cell cycle block followed by the induction of dose-dependent cell death mechanisms. Furthermore, Alkaline and modified comet assay, using Formamido Pyrimidine DNA glycosylase (FPG), revealed that arsenite is able to induce high rates of DNA damage, including oxidation, immediately after treatment. Finally, proteomic analysis by LC−MS/MS label-free shotgun revealed that arsenite is capable of modulating structural and related to redox processes proteins, such as thioredoxin reductase, in addition to altering biological processes related to DNA repair, at the concentration of 30 μM, 12 hours after exposition. Taken together, these results contribute to the understanding of the effects of arsenite at different doses and time after acute exposure on DNA and proteins. It can contribute to expanding knowledge and understanding of the mutagenic and carcinogenic mechanisms induced by the metalloid
Combined expression of JHDM1D/KDM7A gene and long non-coding RNA RP11-363E7.4 as a biomarker for urothelial cancer prognosis.
No full textBladder cancer is the tenth most frequently diagnosed cancer globally. Classification of high- or low-grade tumors is based on cytological differentiation and is an important prognostic factor. LncRNAs regulate gene expression and play critical roles in the occurrence and development of cancer, however, there are few reports on their diagnostic value and co-expression levels with genes, which may be useful as specific biomarkers for prognosis and therapy in bladder cancer. Thus, we performed a marker lesion study to investigate whether gene/lncRNA expression in urothelial carcinoma tissues may be useful in differentiating low-grade and high-grade tumors. RT-qPCR was used to evaluate the expression of the JHDM1D gene and the lncRNAs CTD-2132N18.2, SBF2-AS1, RP11-977B10.2, CTD-2510F5.4, and RP11-363E7.4 in 20 histologically diagnosed high-grade and 10 low-grade tumors. A protein-to-protein interaction network between genes associated with JHDM1D gene was constructed using STRING website. The results showed a moderate (positive) correlation between CTD-2510F5.4 and CTD2132N18.2. ROC curve analyses showed that combined JHDM1D and RP11-363E7.4 predicted tumor grade with an AUC of 0.826, showing excellent accuracy. In conclusion, the results indicated that the combined expression of JHDM1D and RP11-363E7.4 may be a prognostic biomarker and a promising target for urothelial tumor therapy
Control of conventional continuous thickeners via proximal policy optimization.
No full textWith the rise of historical data availability and increased computational power, reinforcement learning (RL)
has become more prominent. It has shown the ability to outperform human knowledge in certain areas. RL is
particularly valuable in control applications due to its generalization, self-adjustment, and independence from
a mathematical model. Despite its potential, there are limited studies and applications focusing on using RL
for mining processes. This study aims to showcase the applicability of RL in the mining industry. An algorithm
was developed using proximal policy optimization (PPO) to control a simulated conventional cylindrical-conical
thickener. The controller’s goal is to adjust the slurry density and solid interface height to produce a material
with a high solid concentration. By regulating the thickener’s output flow and the flocculant dosage in the
incoming slurry, PPO achieves this objective. Through simulation, an RL agent was trained to control the
thickener efficiently, managing flocculant usage and responding appropriately to system disturbances. The
study concludes that applying reinforcement learning holds promise for enhancing mining process control.
However, further research is needed to fine-tune algorithm parameters, enhance design structure, optimize
control, and maximize the technique’s benefits
Dissimilar Trypanosoma cruzi genotypespecific serological profile assessed by Chagas-Flow ATE IgG1 upon benznidazole etiological treatment of chronic Chagas disease.
No full textThe present study aimed to verify the impact of etiological treatment on the genotype-specific serological diagnosis of chronic Chagas disease patients (CH), using the Chagas-Flow ATE IgG1 methodology. For this purpose, a total of 92 serum samples from CH, categorized as Not Treated (NT, n = 32) and Benznidazole-Treated (Bz-T, n = 60), were tested at Study Baseline and 5Years Follow-up. At Study Baseline, all patients have the diagnosis of Chagas disease confirmed by Chagas-Flow ATE IgG1, using the set of attributes (“antigen/serum dilution/cut-off”; “EVI/250/30%”). The genotype-specific serodiagnosis at Study Baseline demonstrated that 96% of patients (44/46) presented a serological profile compatible with TcII genotype infection. At 5Years Follow-up monitoring, NT and Bz-T presented no changes in anti-EVI IgG1 reactivity. However, significant differences were detected in the genotypespecific IgG1 reactivity for Bz-T. The most outstanding shift comprised the anti-amastigote TcVI/(AVI), anti-amastigote TcII/(AII) and anti-epimastigote TcVI/(EVI) reactivities. Regardless no changes in the genotype-specific serology of NT (TcI = 6%; TcII = 94%), distinct T. cruzi genotype-specific sero-classification was detected for Bz-T samples at 5Years Followup (TcII = 100%) as compared to Baseline (TcII = 97%; TcVI = 3%). The anti-trypomastigote TcI/(TI) was the attribute accountable for the change in genotype-specific sero-classification. In conclusion, our findings of dissimilar T. cruzi genotype-specific serology upon Bztreatment re-emphasize the relevance of accomplishing the genotype-specific serodiagnosis during clinical pos-therapeutic management of chronic Chagas disease patients
Geotechnical performance of isotropic and foliated quartzite waste as aggregate for road base and asphalt mixture.
No full textQuartzite mines produce a large amount of waste. Although the reuse of materials is essential for sustainable constructions, little is known about the geotechnical properties of isotropic (massive) and foliated (discontinuous) quartzite waste. In this paper, the potential use of these wastes as base layers and asphalt mixtures were examined by a series of laboratory tests and numerical simulations. This paper presents an analysis of the particle properties, durability, strength, and deformation response of quartzite waste in isotropic (IGM) and foliated granular (FGM) mixtures. Asphalt mixtures with isotropic (IAM) and foliated (FAM) quartzite waste as aggregates are evaluated using Brazilian tensile strength, moisture susceptibility, and repeated-load indirect tension tests, such as the resilient modulus and fatigue. To estimate the performance of these materials as pavement layers, numerical experiments are also carried out using the mechanistic-empirical design framework of the MeDiNa software package. As a base material, the mixtures showed plastic creep responses at the highest stress level (higher permanent strain of 1.2 % at σ3/σd = 360/120 kPa) and negligible expansion. The California bearing ratio (higher than 130 % for both IGM and FGM) and resilient modulus (average of 224 and 130 MPa for IGM and FGM, respectively) greatly exceeded the minimum requirement of Brazilian standards. As asphalt mixtures, both IAM and FAM met the minimum limit of tensile strength, but IAM showed greater stiffness. According to the stress–strain analysis of the MeDiNa software, granular and asphalt mixtures incorporating quartzite waste fulfilled the fatigue crack area and rut depth criteria, falling within the allowed thickness ranges for road pavements subjected to up to 5 × 106 repetitions (medium heavy traffic). This study provides support for the transformation of quartzite waste into a valuable byproduct
Desenvolvimento de um dispositivo intravaginal de progesterona por impressão 3D para pequenos ruminantes.
No full textPrograma de Pós-Graduação em Ciências Farmacêuticas. Escola de Farmácia, Universidade Federal de Ouro Preto.A via intravaginal é uma alternativa para compostos cujas características
inviabilizam o seu uso por via oral, além de ser indicada para formulações de uso
prolongado. Os dispositivos intravaginais de progesterona disponíveis no
mercado são feitos de silicone, material biocompatível, porém não
biodegradável. Este estudo teve como objetivo desenvolver um dispositivo
intravaginal de progesterona (P4) impresso em 3D usando um polímero
biodegradável, ácido polilático (PLA) e polietilenoglicol (PEG), para
sincronização do estro (ES) ou controle do ciclo estral (ECC) em cabras. O
dispositivo foi projetado para fornecer uma liberação sustentada de P4 durante
um período de 7 dias, simulando a fase lútea natural. O dispositivo foi fabricado
usando uma técnica de impressão 3D de modelagem de deposição fundida
(FDM), e suas propriedades físicas e térmicas foram caracterizadas por
microscopia eletrônica de varredura (MEV), calorimetria de varredura diferencial
(DSC) e teste de compressão. Além disso, um estudo in silico foi realizado para
posterior adaptação do modelo feito na cabra para vaca. Adicionalmente, foi
realizado um estudo piloto de esterilização dos filamentos de PLA/PEG/P4 por
óxido de etileno (EtO) e radiação gama. O estudo de liberação in vitro mostrou
uma liberação sustentada de P4 pelo dispositivo, enquanto o estudo in vivo
demonstrou um aumento significativo nos níveis plasmáticos de P4 em cabras
após a inserção do dispositivo. No estudo in vivo, as cabras receberam 0,2 g de
P4 a partir do dispositivo intravaginal PLA/PEG/P4. As concentrações médias de
P4 no plasma em cabras foram de 2,3 a 7,6 ng ml-1 por 7 dias, maiores que 1 ng
ml-1 para simular corpo lúteo. Os resultados sugerem que o dispositivo
intravaginal PLA/PEG/P4 impresso em 3D é uma ferramenta promissora para
ECC em cabras, oferecendo vantagens como design personalizado, doses
variadas de medicamentos em comparação aos métodos tradicionais de
fabricação. O estudo in silico gerou um modelo farmacocinético que prediz o
comportamento de liberação da progesterona nos dispositivos comerciais em
duas raças diferentes de vacas. Os dois métodos de esterilização testados não
degradaram a progesterona nem causaram modificação visível nos filamentos
de PLA/PEG/P4.The intravaginal route is an alternative option for compounds that have
characteristics that make their oral administration unfeasible and for long-term
formulations. Commercially available intravaginal progesterone devices are
made of silicone, a biocompatible material, but it is not biodegradable. This study
aimed to develop a 3D printed intravaginal progesterone (P4) device using a
biodegradable polymer, polylactic acid (PLA) and polyethylene glycol (PEG), for
estrus synchronization (ES) or estrous cycle control (ECC) in goats. The device
was designed to provide a sustained release of P4 over a 7-day period, mimicking
the natural luteal phase. The device was fabricated using a fused deposition
modeling (FDM) 3D printing technique, and its physical and thermal properties
were characterized by scanning electron microscopy (SEM) and differential
scanning calorimetry (DSC) and compression testing. Furthermore, an in silico
study in cows was performed to further adapt the goat model to cows. A pilot
study of ethylene oxide (EtO) and gamma radiation sterilization on PLA/PEG/P4
filaments was also performed. The in vitro release study showed a sustained
release of P4 from the device, and the in vivo study demonstrated a significant
increase in plasma P4 levels in goats after insertion of the device. Goats received
0.2 g of P4 in the PLA/PEG/P4 intravaginal device. Mean plasma P4
concentrations in goats were 2.3 to 7.6 ng ml-1 for 7 days, higher than 1 ng ml-1
to simulate corpus luteum. The results suggest that the 3D printed PLA P4
intravaginal device is a promising tool for ECC in goats, offering advantages such
as personalized design, varied drug doses compared to traditional manufacturing
methods. The in silico study generated a pharmacokinetic model that predicts the
behavior of progesterone in commercial devices in two different breeds. And the
two sterilization methods did not degrade progesterone and did not visibly modify
the PLA/PEG/P4 filaments
Influence of grandparent caregivers on the school longevity of young university students from working class backgrounds.
No full textPrograma de Pós-Graduação em Educação. Departamento de Educação, Instituto de Ciências Humanas e Sociais, Universidade Federal de Ouro Preto.Os avós estão cada vez mais presentes na vida dos netos e, consequentemente, participam direta ou indiretamente do cotidiano escolar. Muitos deles são os principais cuidadores, alguns, se tornam a base e apoio para que jovens possam trilhar estudos longevos. Contribuindo com o debate sobre a importância dos avôs e das avós na escolarização dos netos, esta pesquisa foi desenvolvida a partir do olhar da sociologia da educação e teve como objetivo principal investigar a influência das práticas educativas dos avós cuidadores no processo de escolarização dos jovens de camadas populares que ingressaram em cursos de alto e de baixo prestígio nas ciências humanas da Universidade Federal de Ouro Preto - UFOP, respectivamente Jornalismo e Pedagogia. A partir da abordagem qualitativa, a pesquisa de campo foi realizada em duas etapas. Na primeira, foi aplicado um questionário exploratório a todos os estudantes dos dois cursos. Em seguida, foram realizadas entrevistas semiestruturadas com sete jovens universitários de camadas populares selecionados, três do curso de jornalismo e quatro do curso de pedagogia. Os resultados demonstraram que, com baixa escolaridade, os avós cuidadores não atuaram diretamente no processo de escolarização dos netos, mas influenciaram positivamente na longevidade escolar através do apoio emocional, da manutenção da ordem moral doméstica, do cuidado e do incentivo para os estudos. A pesquisa mostrou ainda, que os estudantes de camadas populares entrevistados utilizaram as políticas de ações afirmativas para conseguirem acessar cursos considerados de alto prestígio social, contudo, encontram desafios para permanecerem na universidade, e aproveitam as oportunidades acadêmicas para complementar a renda, tais como bolsas de iniciações científicas, estágios remunerados, trabalhos informais ou dependem do dinheiro enviado pelos avós e/ou pais. A pesquisa evidenciou também, que não há diferenças significativas de capital cultural e práticas educativas adotadas pelos avós cuidadores nos cursos se jornalismo e pedagogia. Concluímos com a pesquisa, que os avós cuidadores foram figuras centrais para a socialização e para trajetória escolar de sucesso dos universitários entrevistados, como também influenciaram nas tomadas de decisões na vida adulta e nas escolhas acadêmicas e profissionais. Nem todas as relações entre avós e netos contam apenas com sentimentos de amor e carinho. Nas diferentes fases da vida, conflitos podem existir e causar distanciamento entre eles, porém, todos os entrevistados demonstraram gratidão e saudades de conviverem com os avós, reconhecendo a importância e a influência que exercem e exerceram sobre suas vidas.Grandparents are increasingly present in their grandchildren's lives and, consequently, participate directly or indirectly in everyday school life. Many of them are the main caregivers, and some become the basis and support for young people to pursue long-term studies. Contributing to the debate on the importance of grandfathers and grandmothers in the schooling of their grandchildren, this research was developed from the perspective of the sociology of education and its main objective was to investigate the influence of the educational practices of grandparent caregivers on the schooling process of young people from working class backgrounds who entered high and low prestige courses in the humanities at the Federal University of Ouro Preto - UFOP, Journalism and Pedagogy respectively. Using a qualitative approach, the field research was carried out in two stages. In the first, an exploratory questionnaire was administered to all the students on the two courses. Semi-structured interviews were then carried out with seven young university students from working class backgrounds, three from the journalism course and four from the pedagogy course. The results showed that grandparent caregivers with low levels of schooling did not play a direct role in their grandchildren's schooling, but they did have a positive influence on their longevity in school through emotional support, maintaining the moral order of the home, care and encouragement to study. The research also showed that the students from working class backgrounds interviewed used affirmative action policies to gain access to courses considered to be of high social prestige. However, they find it challenging to remain at university, and take advantage of academic opportunities to supplement their income, such as scientific initiation scholarships, paid internships, informal jobs or relying on money sent by their grandparents and/or parents. The research also showed that there are no significant differences in the cultural capital and educational practices adopted by grandparent caregivers on the journalism and pedagogy courses. We conclude from the research that grandparent carers were central figures in the socialization and successful school career of the university students interviewed, as well as influencing decision-making in adult life and academic and professional choices. Not all relationships between grandparents and grandchildren are based solely on feelings of love and affection. In the different stages of life, conflicts can exist and cause distance between them, but all the interviewees showed gratitude and longing for living with their grandparents, recognizing the importance and influence they exert and have exerted on their lives