19341 research outputs found
Sort by
Theoretical, empirical, and methodological aspects of research in ethnomodelling : contributions of GPEUfop investigators.
No full textEsse artigo apresenta os aspectos teóricos, empíricos e metodológicos presentes nas pesquisas
em Etnomodelagem desenvolvidas por 5 (cinco) pesquisadores que são membros de: O
Grupo de Pesquisa de Etnomatemática da Universidade Federal de Ouro Preto – GPEUfop.
Essas pesquisas foram realizadas e defendidas no período de 2017 a 2021 no âmbito do
mestrado Profissional em Educação Matemática da Universidade Federal de Ouro Preto,
UFOP. Os referenciais teóricos foram pautados principalmente nas ideias do Programa
Etnomatemática e na Concepção de Etnomodelagem e de suas abordagens êmica (local),
ética (global) e dialógica (glocal). As metodologias predominantes foram o Método do
Estudo Misto e a adaptação da Teoria Fundamentada nos Dados. Em conclusão, os resultados
dessas pesquisas mostram que a Etnomodelagem pode possibilitar uma ação pedagógica
holística, contextualizada e articuladora entre os conhecimentos matemáticos
escolares/acadêmicos e os saberes e fazeres matemáticos desenvolvidos nos diversos
ambientes culturais.This article presents the theoretical, empirical, and methodological aspects present in
Ethnomodelling research developed by 5 (five) researchers who are members of: The
Ethnomathematics Research Group of the Federal University of Ouro Preto – GPEUfop.
These investigations were carried out and defended from 2017 to 2021 within the scope of
the Professional Master's in Mathematics Education at the Federal University of Ouro Preto,
UFOP. The theoretical references were based mainly on the ideas of the Ethnomathematics
Program and on the Conception of Ethnomodelling and its Emic (local), Etic (global) and
Dialogical (glocal) approaches. The predominant methodologies used were the Mixed
Method Study and the adaptation of the Grounded Theory. In conclusion, the results of these
investigations show that Ethnomodelling can enable a holistic, contextualized, and articulating pedagogical action between school/academic mathematical knowledge and
mathematical knowledge and practices developed in different cultural environments
A piecewise upwind scheme based on quadratic Bézier curves for discretization of convective terms.
No full textEste trabalho apresenta um novo esquema upwind de alta resolução construído com base no conceito das curvas de Bézier que satisfaz diversos critérios de estabilidade no contexto da solução numérica de problemas de transporte dominado por convecção na dinâmica dos fluidos computacional. Oesquema foi testado resolvendo os problemas da advecção linear e o problema de Burgers viscoso. Os resultados dessas simulações sugerem que o esquema proposto é uma alternativa atraente para problemas dominados por convecção quando comparado com outros esquemas da literatura.This work presents a new high-resolution upwind scheme built based on the concept of Bézier curves that satisfy critical stability criteria for the numerical solution of transport problems dominated by convection in computational fluid dynamics. The proposed scheme consists of a piecewise quadratic Bézier curve. The scheme is tested by solving linear advection problems and the viscous Burger problem. The results of these simulations suggest that the proposed scheme is an attractive alternative for problems dominated by convection
Student assistance in higher education : the trajectory of the National Student Assistance Program at the Federal University of Ouro Preto.
No full textO artigo analisa a trajetória do Programa Nacional de Assistência Estudantil (PNAES) na Universidade Federal de Ouro Preto (UFOP), a partir da percepção dos implementadores de alto escalão da instituição. Da mesma forma, analisa os relatórios de avaliação da execução do programa na instituição, no período de 2017 a 2019. O PNAES foi instituído pelo Decreto n.º 7.234/2010 com a finalidade de ampliar as condições de permanência dos jovens na educação superior federal, atendendo, prioritariamente, estudantes oriundos de escolas públicas de educação básica ou com renda familiar per capita de até um salário mínimo e meio. Na UFOP, o programa é executado pela Pró-Reitoria de Assuntos Comunitários e Estudantis, que define os critérios e a metodologia de seleção dos alunos de graduação beneficiados. A pesquisa é quanti-qualitativa, descritiva e se estrutura em três fases: (1) levantamento dos marcos legais/institucionais do programa ao nível nacional e local; (2) análise dos dados disponíveis na UFOP sobre a avaliação da execução do PNAES na instituição, no período de 2017 a 2019; (3) e entrevistas com os burocratas de alto escalão, responsáveis por ações de implementação do PNAES na PRACE. Os dados analisados revelam que, entre 2017 e 2019, em média 11.141 alunos estavam matriculados no ensino presencial na instituição. Destes, 60,7% são egressos de escola pública e 25,2% receberam auxílio financeiro via PNAES. Sobre o desempenho acadêmico, os dados informam que os bolsistas têm melhor coeficiente médio que os demais alunos, além de menor evasão. Os dados indicam que o programa na universidade contempla estudantes oriundos de escolas públicas em situação de vulnerabilidade socioeconômica, contribuindo para a redução de desigualdades sociais por meio da inserção e da permanência dos alunos e, consequentemente, da conclusão do ensino superior.The article analyzes the trajectory of the National Student Assistance Program (PNAES) at the Federal University of Ouro Preto (UFOP), from the perspective of the institution's high-ranking implementers. Likewise, it intends to analyze the evaluation reports of the execution of the program in the institution, in the period from 2017 to 2019. giving priority to students from public basic education schools or with a per capita family income of up to one and a half minimum wages. At UFOP, the program is carried out by the Dean of Community and Student Affairs, which defines the criteria and methodology for selecting beneficiary undergraduate students. The research is quantitative and qualitative, descriptive and is structured in three phases: (1) survey of the legal/institutional frameworks of the program at national and local level; (2) analysis of data available at UFOP on the evaluation of the implementation of the PNAES in the institution, from 2017 to 2019; (3) and interviews with high-ranking bureaucrats, responsible for PNAES implementation actions at PRACE. The data analyzed reveal that, between 2017 and 2019, an average of 11,141 students were enrolled in face-to-face teaching at the institution. Of these, 60.7% are public school graduates and 25.2% received financial aid via PNAES. Regarding academic performance, data indicate that scholarship holders have a better average coefficient than other students, in addition to lower dropout rates. The data indicate that the program at the university includes students from public schools in a situation of socioeconomic vulnerability, contributing to the reduction of social inequalities through the insertion and permanence of students and, consequently, the completion of higher education
Avaliação paleoambiental da Formação Lagoa do Jacaré na sucessão carbonática da Bacia Hidrográfica do Verde Grande – região de Jaíba (MG).
No full textPrograma de Pós-Graduação em Evolução Crustal e Recursos Naturais. Departamento de Geologia, Escola de Minas, Universidade Federal de Ouro Preto.O estudo teve como objetivo realizar a análise paleoambiental da sequência carbonática da
Formação Lagoa do Jacaré na porção leste da Bacia do São Francisco, região norte de Minas
Gerais, área ainda pouco estudada em detalhe. Para isso, duas sucessões aflorantes na região
de Jaíba foram analisadas por meio de dados petrográficos e geoquímicos, que permitiram a
associação de fácies, microfácies e quimioestratigráfica da unidade. As rochas foram
identificadas como uma sequência carbonática formada em ambiente deposicional de rampa
de mar raso dominada por planície de maré, com ocorrência de recifes estromatolíticos e
migração de barras oolíticas via correntes de maré. A sucessão Ribeirão do Ouro,
estratigraficamente localizada no topo da unidade, mostrou três ciclos de raseamento antes do
afogamento total da bacia marcada pelos pelitos da Formação Serra da Saudade. Nessa
sucessão foi observada uma sequência com maior contribuição de terrígenos em comparação
com os carbonatos mais puros da sucessão Córrego Escuro. Todavia, ambas conservam sinais
primários anômalos com assinatura negativa para δ18O e positiva para δ13C, em acordo com os
já registrados pelo Middle Bambuí Excursion–MIBE, indicando um paleoambiente de sistema
de mar aberto com temperaturas amenas e alta produtividade orgânica. De maneira geral, os
resultados obtidos seguiram padrões apresentados para a Formação Lagoa do Jacaré em outras
regiões da Bacia do São Francisco, principalmente a sul e a oeste, indicando que esta unidade
não apresenta variações relevantes em suas características diagenéticas e geoquímicas,
estando sua variabilidade petrográfica condicionada aos ambientes deposicionais dentro da
rampa carbonática.The present study consists in a paleoenvironmental analysis of the carbonate sequence of the
Lagoa do Jacaré Formation in the eastern portion of the São Francisco Basin, located in the
northern region of Minas Gerais, area still little studied in detail. Two outcropping
successions in the Jaíba region were analyzed using petrographic and geochemical data,
which allowed the association of facies, microfacies and chemostratigraphy of the unit. The
rocks were identified as a carbonate sequence formed in an intertidal-dominated shallow sea
ramp depositional environment, with the occurrence of stromatolitic reefs and migration of
oolitic bars through tidal currents. The Ribeirão do Ouro succession, stratigraphically located
at the top of the unit, displayed three shallowing cycles before the total drowning of the basin
marked by the pelites of the Serra da Saudade Formation. In this succession, a sequence with
a higher contribution of terrigens was observed compared to the purest carbonates of the
Córrego Escuro succession. However, both retain anomalous primary signals with a negative
signature for δ18O and a positive one for δ13C, in agreement with those already recorded by
Middle Bambuí Excursion–MIBE, indicating a paleoenvironment of an open sea system with
mild temperatures and high organic productivity. The results obtained presented the same
patterns for the Lagoa do Jacaré Formation in other regions of the São Francisco Basin,
mainly to the south and west, indicating that this unit does not present relevant variations in
its diagenetic and geochemical characteristics, with its petrographic variability conditioned to
depositional environments within the carbonate slope
Computational simulation and big data as technological insertion in industrial processes : a systematic literature review.
No full textA inserção na Indústria 4.0 nas organizações se apresenta como um grande diferencial competitivo, proporcionando inúmeros ganhos em termos de produtividade e retorno de investimento. Com a quarta revolução industrial, vários modelos, ideias e tecnologias foram aprimorados. Dentre elas, destacam-se a Big Data e a Simulação. Diante desse conhecimento, foi realizada neste artigo uma Revisão Sistemática da Literatura (RSL), a fim de identificar os tipos de processos industriais que atualmente utilizam o Big Data e a Simulação para análises e decisões. Para tal fim, foram selecionados dezoito artigos da base científica de dados Scopus e realizada uma análise bibliométrica nesses estudos. Com base nas análises foi possível diagnosticar que existe uma tendência de crescimento da disseminação de conhecimento do tema da pesquisa, o que nos permite acreditar que em breve a utilização dessas tecnologias será realidade em várias indústrias. Nos estudos selecionados para a pesquisa também foi observado que a China se destaca entre os países que investem em pesquisa e desenvolvimento de novas tecnologias voltadas a este estudo. Em relação aos processos industriais identificados, foi possível observar que diferentes segmentos da indústria estão aderindo essas tecnologias, sendo a Simulação mais utilizada nestes processos, quando comparada ao Big Data.The adoption of Industry 4.0 in organizations presents itself as a great competitive advantage, providing numerous gains in terms of return on investment. With the fourth industrial revolution, various models, ideas, and technologies have been developed, among which Big Data and Simulation stand out. In light of this knowledge, a preliminary Systematic Literature Review (SLR) was carried out in this article to identify the types of industrial processes that currently use Big Data and Simulation for decision analysis. For this purpose, eighteen articles were selected from the Scopus scientific database, and a bibliometric analysis of these studies was carried out. Based on the analysis, it was possible to diagnose that there is a trend of growth in the dissemination of research on this topic, which leads us to believe that the use of these technologies will soon be a reality in various industries. China stands out among the countries that encourage these studies. Regarding the identified industrial processes, it was possible to observe that different segments of the industry are adopting these technologies, with Simulation being more widely used in these processes compared to Big Data
Práticas formativas voltadas para o ensino de matemática para estudantes com TDAH e aprendizagem da docência : um estudo com licenciandos(as) em matemática de um instituto federal mineiro.
No full textPrograma de Pós-Graduação em Educação Matemática. Departamento de Educação Matemática, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto.Entendemos que a aprendizagem da docência em Matemática se dá pelo engajamento em práticas
próprias da profissão, a partir das quais os saberes profissionais se vão aprimorando
gradativamente. Pensar nesta aprendizagem em uma perspectiva inclusiva, amplia as demandas e
a necessidade de se desenvolver tanto uma atitude positiva em relação à diversidade, como saberes
específicos que favoreçam a aprendizagem matemática em contextos variados. Este estudo teve
por objetivo investigar como a participação em práticas formativas voltadas para o ensino de
Matemática para estudantes com TDAH contribui para a aprendizagem da docência de futuros(as)
professores(as) de Matemática de um IFMG. Trata-se de uma pesquisa de intervenção de
abordagem qualitativa, na qual se procurou sensibilizar licenciandos(as) em Matemática de uma
instituição pública do interior de Minas Gerais em relação a condição das pessoas com TDAH e
seu impacto na aprendizagem matemática, bem como levá-los a sentirem membros de uma
comunidade cuja prática envolve, entre outras coisas, pensar em alternativas para ensinar
Matemática para pessoas com esse transtorno. O projeto, foi desenvolvido em uma disciplina do
curso de Licenciatura em Matemática, contou com a participação de seis licenciandos(as) ao longo
de sete encontros. A coleta de informações se deu por meio da observação dos encontros, que
também foram gravados em áudio e vídeo, do diário de campo da pesquisadora e de registros
produzidos pelos(as) licenciandos(as) ao longo do projeto. Os resultados sugerem que os(as)
licenciandos(as) ao se engajaram nas práticas formativas desenvolvidas, adotaram uma postura
mais proativa e central, se apropriando de elementos acerca da prática docente e refletindo sobre
a mesma. Além de desenvolverem uma postura mais sensível em relação aos(às) estudantes com
TDAH, mas pensando na sala de aula como espaço para todos e todas.We understand that learning to teach Mathematics is by engaging in the profession's practices,
from which professional knowledge is gradually improved. In this sense, thinking about the
teaching learning from an inclusive perspective involves both developing a favourable attitude
towards diversity and promoting training practices that favor this perspective. This study
investigated possible contributions of participation in formative practices aimed at teaching
Mathematics to students with ADHD for the teaching-learning process of Mathematics graduates
at an IFMG (Federal Institute in Minas Gerais). This intervention research is a qualitative approach
based on notions related to the learning proposed by Jean Lave and Ettienne Wenger and developed
through a teaching project carried out with Mathematics teachers from an IFMG. We developed
the project over seven meetings in a mandatory subject of the course. Six undergraduate students
participated with the teacher who was responsible for the class. Several guests attended the
meetings as well. We collected the information observing the meetings, through recorded audio
and video, from the researcher's field diary and records produced by the undergraduate students
throughout the project. The results suggest that the undergraduates engaged in the training
practices developed gradually adopted a more proactive and central stance, appropriating
information about ADHD and Mathematics teaching for people diagnosed with this disorder. In
addition, they developed a more sensitive attitude towards students with ADHD and gained greater
ease in planning Mathematics classes while still understanding the classroom as a space for
everyone
Innovation in ophthalmology and dentistry services : benefits and challenges of using AI.
No full textThe development of Artificial Intelligence (AI) is revolutionizing different organizational contexts, including health
services. Among these services, ophthalmology and dentistry stand out for being areas with intense use of technological
innovations, mainly for obtaining images. The use of AI promotes innovation in the provision of these services, helping the
activities of professionals working in this area. However, the literature is still scarce on the perception of these professionals
regarding the benefits and challenges arising from the use of these innovations. In this sense, the objective of this article is
to evaluate the perception of ophthalmologists and dentists in the use of AI technological innovations in relation to the
benefits for patient care, as well as the challenges for its implementation and adoption. This is a qualitative research that
was developed from data collected, through a questionnaire, with 18 health professionals, 10 ophthalmologists, and 8
dentists. As a result, it was observed that the main benefits found with the use of AI-assisted innovations were diagnostic
support, mainly in increasing assertiveness and reducing the time to detect diseases. In addition, these innovations provided
an increase in the time of the doctor-patient relationship, reflecting greater satisfaction of the users of these health services.
The challenge presented in the implementation of innovations in ophthalmology and dentistry was the lack of incentives
from health plans in the application of AI. Without financial incentives, the costs of these innovations become a significant
barrier to adoption. To overcome the barrier related to cost, some ophthalmologists acquired equipment in partnership with
other health professionals, enabling the sharing and rationalization of costs related to the technological resource. Finally, in
the perception of both professionals (ophthalmologists and dentists), AI promotes innovations in health services,
complementing and not substituting the clinical diagnosis of a specialized professional
Plasmin and plasminogen prevent sepsis severity by reducing neutrophil extracellular traps and systemic inflammation.
No full textSepsis is a lethal syndrome characterized by systemic inflammation and abnormal coagulation.
Despite therapeutic advances, sepsis mortality remains substantially high. Herein, we investigated
the role of the plasminogen/plasmin (Plg/Pla) system during sepsis. Plasma levels of Plg were
significantly lower in mice subjected to severe compared with nonsevere sepsis, whereas systemic
levels of IL-6, a marker of sepsis severity, were higher in severe sepsis. Plg levels correlated
negatively with IL-6 in both septic mice and patients, whereas plasminogen activator inhibitor-1
levels correlated positively with IL-6. Plg deficiency render mice susceptible to nonsevere sepsis
induced by cecal ligation and puncture (CLP), resulting in greater numbers of neutrophils and M1
macrophages, liver fibrin(ogen) deposition, lower efferocytosis, and increased IL-6 and neutrophil
extracellular trap (NET) release associated with organ damage. Conversely, inflammatory features,
fibrin(ogen), and organ damage were substantially reduced, and efferocytosis was increased by
exogenous Pla given during CLP- and LPS-induced endotoxemia. Plg or Pla protected mice from
sepsis-induced lethality and enhanced the protective effect of antibiotics. Mechanistically, Plg/Pla–
afforded protection was associated with regulation of NET release, requiring Pla-protease activity
and lysine binding sites. Plg/Pla are important host-protective players during sepsis, controlling
local and systemic inflammation and collateral organ damage
Lithological control on the formation of ferruginous duricrusts in the Espinhaço Range (Minas Gerais, Brazil).
No full textThe Espinhaço Range is the scene of a long history of exposure to chemical weathering and erosion processes since the Cretaceous. As a result, ferruginous duricrusts can be considered as the fingerprint of the long-term surface process and may provide us critical clues about changes in paleo-environmental features during the Cenozoic. In addition, specifically for the Diamantina plateau, located in the state of Minas Gerais (Brazil), there is great interest in studying the duricrusts of the Espinhaço Range, because they are associated with diamond mining, explored since the eighteenth century and which gave its name to the region. Even so, few studies have contributed to understanding their formation and morphological diversity. Mineralogical, geochemical, and micromorphological studies were undertaken to understand the processes involved in the formation of the two representative types of ferruginous duricrust, linked to phyllites of Espinhaço Supergroup: platy and massive types. The platy duricrust develops from the weathering of a banded ilmenite-hematite phyllite where the alteromorphization of its compositional banding and original foliation leads to the formation of an isalteritic duricrust. The massive duricrust, associated with diamond mining, is genetically linked to a quartz-phengite phyllite. Both duricrust profiles show relative enrichment in Fe and P and depletion of the other major elements compared to the saprolite, however, the iron concentration was 10 times greater in the massive than the platy duricrust. The REEs show similar distribution patterns with preferential leaching in both duricrusts. The compositional and textural variation of the phyllite in the Diamantina Plateau leads to the distinct evolution of two representative duricrusts profiles. The mineralogical, micromorphological, and geochemical analyses reinforce the lithological control in the formation of these two different types of ferruginous duricrusts in the study area, located in similar topographic and climatic conditions
Econometric model of iron ore through principal component analysis and multiple linear regression.
No full textPrice of iron ore is affected by instabilities of microeconomic balance between supply and demand. Periods of equilibrium adjustment result in huge swings, growth or global recession. They also impact the viability of mineral enterprises and generate consequences to important global economic scenarios. This research aims to evaluate the market variables capable of influencing the price of iron ore through multivariate statistical techniques. Principal component analysis and multiple linear regression, booth multivariate statistical techniques were used. The studied variables were rate export of iron ore and concentrates from Brazil, steel production from China, steel production from Japan, production from Europe, steel production from the United States, steel production from India, steel price, coal price, China’s Construction Gross Domestic Production, United States construction index, oil price and global oil production. First
three components explained 89.12% of the variability of the data matrix. Multiple linear
regression highlighted the significance of five variables. They are export iron ore from
Brazil, steel production from China, price of coal, steel production from India and price
of steel