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Utilizando o Google Forms em uma atividade matemática gameficada para o Ensino Fundamental.
No full textEste artigo apresenta um Produto Educacional advindo de uma pesquisa realizada no
Mestrado Profissional em Educação Matemática da Universidade Federal de Ouro
Preto. A pesquisa, basicamente qualitativa em seus pressupostos e metodologia,
contemplou a apresentação e a exploração de diversas ferramentas da plataforma
Google for Education em encontros de formação continuada com professores de
Matemática. A atividade matemática que constitui essencialmente o Produto
Educacional foi elaborada e implementada no Google Forms, buscando considerar
alguns elementos de uma metodologia ativa chamada gameficação. Após a realização
e a avaliação da atividade por parte dos professores participantes, de forma unânime,
foram destacadas as contribuições específicas da atividade matemática gameficada
para a prática docente de Matemática no Ensino Fundamental, para a aprendizagem
dos alunos em habilidades relacionadas a funções e, ainda, para a formação do
professor em relação à utilização de Tecnologias Digitais no contexto educacional.
Mais geralmente, as conclusões da pesquisa revelaram que as oportunidades de
aprendizagem e de desenvolvimento profissional foram as grandes contribuições para
a formação continuada dos professores de Matemática, destacadamente, a
possibilidade de experimentação das ferramentas da plataforma Google for Education,
dentre elas, especificadamente, o Google Forms. Nas considerações finais do artigo,
apontamos para a importância da elaboração de atividades matemáticas que
incentivem e possibilitem aos professores de Matemática a utilização de Tecnologias
Digitais de forma colaborativa e coletiva na construção de conhecimentos
matemáticos, junto aos seus pares e aos seus alunos.This article presents an Educacional Product resulting from research conducted in the
Professional Master Degree in Mathematics Education at the Federal University of
Ouro Preto. The research, primarily qualitative in its assumptions and methodology,
included the presentation and the exploration of several tools of the Google for
Education platform in continuing education meetings with Mathematics teachers. The
mathematical activity that essentially constitutes the Educational Product was
designed and implemented in Google Forms, seeking to consider some elements of
an active methodology called gamification. After the performance and evaluation of the
activity by the participating teachers, unanimously, the following specific contributions
of the gamified mathematical activity were: for the teaching practice of Mathematics in
Elementary Education, for the students’ learning in skills related to functions and, yet,
for teacher education in relation to the use of Digital Technologies Digitais in
educational context. More generally, the research conclusions revealed that the
opportunities for learning and professional development were the great contributions
to the continuing education of Mathematics teachers, notably the possibility of
experimenting with the tools of Google for Education platform, including specifically
Google Forms. In the final considerations of the article, we point to the importance of
developing mathematical activities that encourage and enable Mathematics teachers
to use Digital Technologies collaboratively and collectively in the construction of
mathematical knowledge, with their peers and students
A novel approach to measure the chip formation temperature using the implanted thermocouple method.
No full textSimultaneous measurement of the temperature in different regions during machining operations presents many limitations. Currently, only orthogonal cutting using a infrared camera allows the simultaneous measurement of temperature in different regions. Additionally, temperature measurement in certain regions is a challenge, for instance, in the chip/tool interface and inside the chip. The application of advanced sensors and the adaptation of well-established techniques in regions of difficult access, such as the chip-tool interface and the chip itself, have been the subject of research to allow the better understanding of the heat generation and temperature evolution during machining operations. This work investigates the application of the inserted thermocouple method to measure the temperature inside the chip during its formation, together with the tool-workpiece thermocouple method to compare the effect of the cutting parameters on both the chip-tool inter face and chip temperature. Orthogonal cutting of AISI 1020 steel was performed using cemented tungsten carbide bits. The findings indicated that both methods were able to assess the influence of the investigated parameters and that temperature presented the same behavior, in spite of the differences in absolute values (higher temperatures were recorded using the tool-workpiece thermocouple). Temperature increased with cutting speed, decreased with the elevation of the undeformed chip thickness and was not affected by width of cut. The highest temperature (668 °C) was observed at the tool-workpiece interface using a cutting speed of 120 m/min, undeformed chip thickness of 0.1 mm and width of cut of 1.5 mm
A utilização do software Geogebra nos cursos de licenciatura e de bacharelado em matemática da Universidade Federal de Ouro Preto : potencialidades, realidades e perspectivas.
No full textPrograma de Pós-Graduação em Educação Matemática. Departamento de Educação Matemática, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto.Esta dissertação apresenta uma pesquisa que tem como finalidade discutir a utilização do
software GeoGebra na prática docente de professores de Matemática e de Educação
Matemática que atuam na formação inicial de professores e de bacharéis em Matemática.
O trabalho se fundamentará em reflexões acerca de pesquisas sobre a utilização do
GeoGebra nos processos de ensino e de aprendizagem em disciplinas de Matemática e de
Educação Matemática integrantes da matriz curricular de cursos de Licenciatura e de
Bacharelado em Matemática. A metodologia adotada contempla uma análise documental
dos Projetos Pedagógicos dos Cursos (PPC) e a realização de entrevistas com
coordenadores e professores dos cursos de Licenciatura e de Bacharelado em Matemática
da Universidade Federal de Ouro Preto (UFOP). A análise dos dados produzidos apontou
que: existem múltiplas potencialidades de utilização do GeoGebra nos processos de
ensino e de aprendizagem de diversas disciplinas dos cursos de Licenciatura e de
Bacharelado em Matemática; no caso da UFOP, os PPC dos referidos cursos mostram
uma realidade ainda distante da exploração de todas as potencialidades apresentadas,
ainda que os coordenadores e professores reconheçam muitas potencialidades e, de fato,
utilizem o GeoGebra em diversas disciplinas ministradas; exatamente por causa dessas
realidades, existem muitas perspectivas de troca de experiências entre professores que,
eventualmente, podem contribuir para transformar as realidades observadas. As
expectativas de contribuição deste trabalho são apresentar sugestões para o professor do
Ensino Superior a respeito da utilização do GeoGebra em disciplinas de Matemática e
constituir-se num referencial para outras pesquisas em Educação Matemática.This dissertation presents research whose objective is to discuss the use of the GeoGebra
software in the teaching practice of Mathematics and Mathematics Education teachers
who provide initial training for teachers and graduates in Mathematics. The work will be
based on reflections on research on the use of GeoGebra in teaching and learning
processes in the subjects of Mathematics and Mathematics Education, which are part of
the curriculum of bachelor's and degree courses in Mathematics. The methodology
adopted includes documentary analysis of the Course Pedagogical Projects (PPC) and
interviews with coordinators and teachers of the Bachelor's and Degree courses in
Mathematics at the Federal University of Ouro Preto (UFOP). The analysis of the data
produced showed that: there are multiple potential uses of GeoGebra in the teaching and
learning processes of various subjects in the Bachelor's and Bachelor's Degree courses in
Mathematics; in the case of UFOP, the PPC of the aforementioned courses show a reality
that is still far from exploring all the potential presented, even though the coordinators
and teachers recognize many potentialities and, in fact, use GeoGebra in several subjects
taught; Exactly because of these realities, there are many perspectives for exchanging
experiences between teachers that, eventually, can contribute to transforming the
observed realities. The expected contribution of this work is to present suggestions for
Higher Education teachers regarding the use of GeoGebra in Mathematics subjects and
to constitute a reference for other research in Mathematics Education
Avaliação biometálica de soro e urina em pacientes portadores de declínio cognitivo.
No full textPrograma de Pós-Graduação em Biotecnologia. Núcleo de Pesquisas em Ciências Biológicas, Pró-Reitoria de Pesquisa de Pós Graduação, Universidade Federal de Ouro Preto.O envelhecimento populacional de caráter progressivo, fenômeno inicialmente relatado em
países desenvolvidos e altamente industrializados, passou a ser evidenciado nos últimos anos
em nações em desenvolvimento, como é o caso do Brasil. Tais fatos podem ser creditados ao
maior acesso à tratamentos médicos, muitas vezes preventivos, com também a melhorias
nutricionais, para uma parcela importante da população. No entanto, o envelhecimento trará
consigo o aumento da incidência de doenças degenerativas, sendo objeto deste estudo aquelas
que acabarão por afetar o sistema nervoso central (SNC). A Deficiência Cognitiva Maior
(DCM), anteriormente denominada demência, em suas mais variadas formas, é considerada
uma prioridade mundial de saúde pública. A cada ano são contabilizados 7,7 milhões de
novos casos. Estima-se que esse número será de 115,4 milhões em 2050. Uma das hipóteses
apregoadas pela literatura médica correlaciona a deposição de biometais no SNC, com
ocorrência de desequilíbrio redox, ativação de cascatas metabólicas, apoptose e morte
neuronal, como fatores associados à ocorrência de doenças degenerativas. Apesar disso, um
número considerável de idosos não evolui com alterações degenerativas deste sistema
orgânico. Neste trabalho foram avaliados 41 idosos saudáveis e 94 idosos com declínio
cognitivo, com diagnóstico clínico de Deficiência Cognitiva Leve (DCL) e de Deficiência
Cognitiva Maior (DCM). Os participantes dos três grupos foram submetidos à exames de
rastreio de condições que possam desencadear declínio cognitivo, com exclusão de 35 idosos
que apresentaram fatores de confusão para os diagnósticos de DCL e DCM. Os pacientes que
permaneceram grupos DCL e DCM foram submetidos a avaliação clínica inicial pela
aplicação do Mini-Exame do Estado Mental. Amostras de soro e urina dos participantes dos
três grupos foram submetidas a análise biometálica por espectrometria óptica com plasma
indutivamente acoplado. Os resultados mostraram uma redução de alumínio em amostras de
soro de pacientes do grupo DCM, o que não foi observado nas amostras de urina desse grupo.
Esse fato pode estar associado à deposição desse metal em outro(s) tecido, inclusive no tecido
cerebral Apesar das inferências, são necessárias análises mais aprofundadas, inclusive de
biópsia cerebral, para uma conclusão que permita o desenvolvimento de um biomarcador
metálico que possa auxiliar no diagnóstico do declínio cognitivo.The progressive population aging, initially reported in developed and highly industrialized
countries, has become increasingly evident in recent years in developing nations, such as
Brazil. This trend can be attributed to greater access to medical treatments, often preventive,
as well as nutritional improvements for a significant portion of the population. However,
aging brings with it a higher incidence of degenerative diseases, with this study focusing on
those that affect the central nervous system (CNS). Major Cognitive Impairment (MCI),
previously referred to as dementia, in its various forms, is considered a global public health
priority. Each year, 7.7 million new cases are reported, and this number is projected to reach
115.4 million by 2050. One hypothesis proposed in the medical literature correlates the
deposition of biometals in the CNS with redox imbalance, activation of metabolic cascades,
apoptosis, and neuronal death, as factors associated with the occurrence of degenerative
diseases. Despite this, a considerable number of elderly individuals do not develop
degenerative changes in this organic system. This study evaluated 41 healthy elderly
individuals and 94 elderly individuals with cognitive decline, clinically diagnosed with Mild
Cognitive Impairment (MCI) and Major Cognitive Impairment (MCI). Participants from the
three groups underwent screening for conditions that could trigger cognitive decline, with 35
elderly individuals excluded due to confounding factors for the diagnosis of MCI and Major
Cognitive Impairment. The remaining patients in the MCI and Major Cognitive Impairment
groups underwent an initial clinical evaluation using the Mini-Mental State Examination.
Serum and urine samples from participants in the three groups were subjected to biometal
analysis through inductively coupled plasma optical emission spectrometry. The results
showed a reduction in aluminum levels in serum samples from patients in the Major
Cognitive Impairment group, which was not observed in the urine samples from this group.
This finding may be associated with the deposition of this metal in other tissues, including
brain tissue. Despite these inferences, more in-depth analyses, including brain biopsy, are
necessary to draw a conclusion that could lead to the development of a metallic biomarker to
aid in the diagnosis of cognitive decline
Global trend of ethnomathematics studies of the last decade : a bibliometric analysis.
No full textThis study aims to investigate ethnomathematics research trends through
bibliometric analysis on widely distributed Google Scholar (GS) and Scopus
databases. One thousand seventy-seven papers were reviewed from GS and
Scopus databases searched using Harzing's Publish on 9 January 2023. A
descriptive study approach was used to investigate the data. The result of this
study is that the number of ethnomathematics studies has increased over the
last decade (2012-2022). The most productive author based on GS is Rosa
from Brazil, and the full author based on Scopus is Widada from Indonesia.
The principal authors with the highest citations are Ascher, based on GS, and
Muhtadi, based on Scopus, with the highest citations. The Journal of Physics:
Conference Series (JPCS) in the last decade is the most crucial source of
ethnomathematics documents. Based on VosViewer visualization, Rosa is the
author who has the most co-authorship papers and total link strength. The
VosViewer displays four clusters related to Ethnomathematics: mathematics
education, skills, ethnomathematics studies, and geometry. Our strong
recommendations regarding this study are ethnomathematics research related
to literacy, numeracy, technocracy, and mathematical abilities. The results can
assist relevant researchers in understanding trends in ethnomathematics
research and recommend guidelines for other studies
Crystallographic and mineralogical analyses of quartz extractedfrom the mine of Terra Branca, Minas Gerais, Brazil.
No full textIn this study, a structural and chemical analysis of quartz from a mine in Terra Branca, Bocaiúva, MG, Brazil was performed. The assay was performed by chemical analysis using XRF, XRD, and Rietveld refinement. In the first two analyses, a high degree of similarity between the samples was found; however, differences were revealed using the Rietveld method. In the latter, it is possible to quantify the degree of perfection of the crystal lattice using its parameters for the unit cell of the crystal. Based on the results discussed above, we can conclude that the hyaline sample has a higher degree of order than the milky quartz sample. This difference is because the unit cell of the milky quartz is more expanded; that is, it has a larger volume, which means that the crystal has deviations from the ideal organization, which can manifest as defects, cracks, and inclusions of air bubbles. The SEM and TEM images also reveal differences between the two samples in terms of morphology. A map of the pore size distribution was also obtained in this study
Bionarrativas sociais e a educação ambiental : um estudo das percepções e vivências ambientais de estudantes de uma escola pública na cidade de Ouro Preto.
No full textPrograma de Pós-Graduação em Ensino de Ciências, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto.A pesquisa investiga possibilidades de Educação Ambiental Urbana tendo como objeto de estudo as percepções e vivências ambientais de estudantes do ensino fundamental de Ouro Preto. Pautamos nosso trabalho na perspectiva dos diferentes modos de existir e ser dos sujeitos em seu território, apresentados na abordagem da Educação Ambiental desde el Sur, bem como nas produções autorais propostas pelos pesquisadores da Caravana da Diversidade, estudiosos da sociobiodiversidade, enquanto tema para o ensino de Biologia. Dessa maneira, esta pesquisa tem como objetivo: desenvolver uma proposta para promoção de Educação Ambiental contextualizada no território por meio de uma oficina pedagógica para produção de Bionarrativas Sociais, procurando observar as temáticas e apropriações elaboradas por estudantes de uma turma dos anos finais do ensino fundamental de uma escola da rede pública municipal de Ouro Preto, MG. O trabalho tem abordagem qualitativa e envolve a análise textual discursiva. Por meio da oficina desenvolvida, buscou-se compreender a relação dos estudantes com o território e, assim, elucidar as construções ideológicas, políticas, socioculturais e ambientais que se apresentarem. Diante do exposto, construímos os metatextos que apresentam os resultados e discussão, sendo eles: 1º - Elementos mobilizadores para Educação Ambiental contextualizada no território; 2º – Bionarrativas Sociais: um olhar dos estudantes sobre si e sobre o território. Ao analisarmos os fenômenos que se mostram em nossa pesquisa, procuramos reverberar a riqueza dos detalhes, sentimentos, encantamentos, retratados pelos estudantes. Consideramos que a oficina apresentou potencial para integrar os saberes populares, as vivências individuais e coletivas no território e a autoria como caminhos para uma educação ambiental contextualizada no território. Também se fez como espaço de escuta, sendo atenta ao que nossos referenciais denominam colonialidade do ser, do saber, do poder e da natureza. Contudo, nos deparamos com os desafios de mobilizar estes estudantes para que se sentissem confortáveis para expressar suas ideias, opiniões e sentimentos, sendo que eles muitas vezes se mostravam resistentes; bem como despertar nos estudantes maior segurança para a escrita mais autoral.The research investigates possibilities for Urban Environmental Education, taking as its object of study the environmental perceptions and experiences of elementary school students in Ouro Preto. We base our work on the perspective of the different ways of existing and being of the subjects in their territory, presented in the approach of Environmental Education desde el Sur, as well as in the authorial productions proposed by the researchers of the Caravana da Diversidade, scholars of socio-biodiversity, as a theme for teaching of Biology. Therefore, this research aims to: develop a proposal to promote Environmental Education contextualized in the territory through a pedagogical workshop for the production of Social Bionarratives, seeking to observe the themes and appropriations created by students from a class in the final years of elementary school from a municipal public school in Ouro Preto, MG. The work has a qualitative approach and involves a discursive textual analysis. Through the workshop developed, we seek to understand the students' relationship with the territory and, thus, elucidate the ideological, political, sociocultural and environmental constructions that arise. Given the above, we built the metatexts that present the results and discussion, which are: 1st - Mobilizing elements for Environmental Education contextualized in the territory; 2nd – Social Bionarratives: students’ perspective on themselves and the territory. When analyzing the characteristics shown in our research, we seek to reverberate a wealth of details, feelings, enchantments, portrayed by the students. We consider that the workshop had the potential to integrate popular knowledge, individual and collective experiences in the territory and authorship as paths to environmental education contextualized in the territory. It was also created as a space for listening, paying attention to what our references call the coloniality of being, knowledge, power and nature. However, we were faced with the challenges of mobilizing these students so that they felt comfortable expressing their ideas, opinions and feelings, and they were often resistant; as well as awakening students’ confidence in authorial writing
An integrated simulation and optimization tool for short-term mining planning problems with different prioritization among competing plant targets.
No full textThis work proposes a tool that integrates a hierarchical mixed-integer linear programming (MILP) model with a discrete event simulation (DES) model to simulate an annual mining plan discretized in shift-by-shift periods. The hierarchical MILP model has ten objectives and optimizes the shift schedule according to the available materials in the free faces at each simulation moment. The DES model simulates the realization of this schedule considering the uncertainties and interactions between the mine’s equipment. Four scenarios from a Brazilian mining company were analyzed. These differ regarding the prioritization order of the MILP goals and the plants’ grade tolerance. The results report that prioritizing the plant with the highest value-added product results in a 7.0% production gain. Additionally, prioritizing the particle size target of the plants leads to a 2.5% production gain compared to prioritizing the element grade targets
Selective Ru(II)/benzoate complexes against triple-negative breast tumor cells and their interactions with DNA and BSA.
No full textNew ruthenium(II) complexes bearing benzoate (AB) ligand with the general formula [Ru(AB)(bipy)(P–P)]PF6, where 2,2′-bipyridine (bipy) and different diphosphine ligands, (P–P) = 1,2′-bis(diphenylphosphine)ethane (dppe, 1), 1,3′-bis(diphenylphosphine)propane (dppp, 2) and 1,2′-bis(diphenylphosphine)ferrocene (dppf, 3), were synthesized. The compounds were characterized by molar conductivity, elemental analysis, cyclic vol- tammetry, infrared and UV–Vis spectroscopies, NMR, and by single-crystal X-ray diffraction for complexes 1 and 2. The complexes showed a weak interaction to CT-DNA through DNA minor groove, with Kb values at around 103 -104 M− 1 . CT-DNA interaction assays by viscosity and circular dichroism (CD) suggested that the compounds do not significantly alter the secondary DNA structure. The complexes are cytotoxic against MDA-MB-231, MCF- 7 (breast) and A549 (lung) tumor cell lines, with IC50 values in the range of 1 to 17 μM. The compounds 1-3 showed high selectivity against triple-negative breast tumor cells. Remarkably, complexes 1 and 3 show greater cytotoxic activity against cells than cisplatin, being promising agents for tumor treatment
Sustainable structural lightweight concrete with recycled polyethylene terephthalate waste aggregate.
No full textPlastic is a widely consumed material with a high decomposition time, occupying sig nificant space in landfills and dumps. Thus, strategies to reuse plastic waste are imperative for environmental benefit. Plastic waste is a promising eco-friendly building material for cement-based composites due to its reduced specific gravity and thermal conductivity. However, this waste reduces the composites’ mechanical strength. This work aims to produce and evaluate lightweight concretes made with only lightweight aggregates and mostly recycled plastic aggregates. Initially, an optimized dosage approach for lightweight concrete is presented. The mixture proportion of the lightweight concrete was based on the performance of mortars with the complete replacement of natural aggregate by recycled polyethylene terephthalate (PET) aggregates. The PET aggregates showed irregular shapes, impairing workability and providing lightweight concretes with around 18% water absorption and 21% void index. However, the concretes presented significantly low-unit weight, approximately 1200 kg/m3 . This work presented a structural lightweight concrete (ACI 213-R) using only lightweight aggregates and mostly plastic waste aggregate, with a compressive strength of up to 17.6 MPa, a unit weight of 1282 kg/m3, and an efficiency factor of 12.3 MPa·cm3/g. The study shows that with an optimum dosage, reusing plastic waste in concrete is a viable alternative contributing to environmental sustainability