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Contextos e trajetórias da implementação das comissões de heteroidenificação : uma análise a partir da experiência da Universidade Federal de Ouro Preto.
No full textPrograma de Pós-Graduação em Educação. Departamento de Educação, Instituto de Ciências Humanas Sociais, Universidade Federal de Ouro Preto.Esta pesquisa de mestrado em Educação analisa os contextos e trajetórias da
implementação das Comissões de Heteroidentificação na Universidade Federal de Ouro Preto
(UFOP). No Brasil, através da Lei 12.711/12, foi estabelecida uma política que determina a
reserva mínima de 50% das vagas em universidades e instituições federais de ensino técnico de
nível médio para estudantes provenientes de escolas públicas. Essa reserva é destinada a
indivíduos que se autodeclaram como pretos, pardos, indígenas ou pessoas com deficiência,
levando em consideração a proporção desses grupos populacionais na localidade da instituição e
os dados do último censo realizado pelo Instituto Brasileiro de Geografia e Estatística (IBGE) e
dentro desse sistema de reserva, há a estipulação de que 25% das vagas sejam reservadas para
estudantes provenientes de famílias com renda per capita de até um salário e meio.
Posteriormente, para assegurar que as vagas reservadas para pretos e pardos sejam destinadas aos
legítimos beneficiários, foram implementadas as Comissões de Heteroidentificação. O percurso
metodológico abrange as seguintes fases: 1. Revisão de literatura; 2. Levantamento e análise de
legislações, normativas e documentos nacionais relacionados a Política de Cotas; 3. Levantamento
e análise de documentos da UFOP; 4. Observação Participante; 5. Levantamento de dados
relacionados ao perfil dos estudantes matriculados na UFOP; 6. Mapeamento da instituição e
sujeitos da pesquisa; 7. Realização das entrevistas. A escolha dos participantes levou em
consideração que a implementação de políticas públicas é um processo complexo, dinâmico e
político, constituindo trajetórias que são afetadas por diferentes contextos, territórios e pessoas.
Nesse sentido, os dados estão organizados nas seguintes dimensões: i. Percepção dos membros
das Comissões de Heteroidentificação sobre sua atuação; o funcionamento e efetividade das
comissões; ii. Percepção dos candidatos que se autodeclaram negros para vagas reservadas, acerca
da atuação das Comissões de Heteroidentificação na UFOP; iii. Efeitos da Implementação das
Comissões de Heteroidentificação na UFOP. A pesquisa demonstra que a avaliação da
autodeclaração racial no Brasil enfrenta desafios devido à complexidade das definições raciais e à
ausência de critérios objetivos claros. As Comissões de Heteroidentificação são essenciais para a
eficácia da política de cotas, no entanto, a análise das experiências dos discentes e dos membros
das comissões, junto às discussões teóricas, aponta a necessidade de aprimoramentos para garantir
a imparcialidade e a justiça do processo.This master's research in Education analyzes the contexts and trajectories of the
implementation of Heteroidentification Commissions at the Federal University of Ouro Preto
(UFOP). In Brazil, through Law 12.711/12, a policy was established that mandates a
minimum reservation of 50% of spots in universities and federal technical high schools for
students from public schools. This reservation is designated for individuals who self-identify
as black, brown, indigenous, or persons with disabilities, taking into account the proportion of
these population groups in the locality of the institution and data from the latest census
conducted by IBGE. Within this reservation system, it is stipulated that 25% of the spots are
reserved for students from families with a per capita income of up to one and a half times the
minimum wage. Subsequently, to ensure that the reserved spots for black and brown
individuals are allocated to the rightful beneficiaries, Heteroidentification Commissions were
implemented. The methodological approach encompasses the following phases: 1. Literature
review; 2. Survey and analysis of legislation, regulations, and national documents related to
the Quota Policy; 3. Survey and analysis of UFOP documents; 4. Participant observation; 5.
Survey of data related to the profile of students enrolled at UFOP; 6. Mapping of the
institution and research subjects; 7. Conducting interviews. The selection of participants
considered that the implementation of public policies is a complex, dynamic, and political
process, constituting trajectories affected by different contexts, territories, and people. In this
regard, the data are organized into the following dimensions: i. Perception of the members of
the Heteroidentification Commissions about their performance; the functioning and
effectiveness of the commissions; ii. Perception of candidates who self-identify as black for
reserved spots, regarding the performance of the Heteroidentification Commissions at UFOP;
iii. Effects of the Implementation of Heteroidentification Commissions at UFOP. The
research shows that the assessment of racial self-declaration in Brazil faces challenges due to
the complexity of racial definitions and the lack of clear objective criteria.
Heteroidentification Committees are essential for the effectiveness of the quota policy;
however, the analysis of the experiences of students and committee members, along with
theoretical discussions, highlights the need for improvements to ensure the impartiality and
justice in the process
Insights into manganese removal from mine water by Chlorella vulgaris.
No full textMicroalgae have been extensively applied on bioremediation processes and biosorption is usually considered the main mechanism describing metal removal from wastewaters. Nevertheless, the water chemistry is modifed during algal growth and the increase in both pH and oxygen concentrations result in metal precipitation. In this regard, the aim of the current study is to investigate how these two phenomena promote metal removal from waters, applying Chlorella vulgaris and high concentrations of manganese (50 mg/L)—one of the most common and difcult metals to be removed from fresh- and wastewaters alike. Triplicate experiments were carried out at 25 °C and 150 min−1 under 24 h/day of artifcial light and revealed that the growth of C. vulgaris was associated with a reduction in Mn2+ concentration to values below 1 mg/L, as the pH changed from 6.2 to 9.6, within 14 days. Biosorption as a removal mechanism appears not to be relevant as the manganese uptake by the C. vulgaris cells was actually reduced from 10.9 mg/g (10 min) to 0.9 mg/L, within 24 h of testing, indicating desorption of the manganese initially adsorbed. Furthermore, the formation of brown precipitates containing Mn3+/Mn4+ oxy-hydroxides was observed, which was confrmed upon reaction with leucoberbelin blue (LBB) solutions. In addition, no evidence of the participation of extracellular materials on Mn2+ removal was observed. These outcomes support the hypothesis that an increase in pH, resulting from the growth of C. vulgaris, is responsible for increasing pH to values above 8.0, values in which Mn2+ oxidation is catalysed
Integration of biophysical and biological approaches to validate fragment-like compounds targeting L,D-transpeptidases from Mycobacterium tuberculosis.
No full textTuberculosis is one of the major causes of death worldwide; more than a million people die every year because of this infection. The constant emergency of Mycobacterium tuberculosis resistant strains against the most used treatments also contributes to the burden caused by this disease. Consequently, the development of new alternative therapies against this disease is constantly required. In recent years, only a few molecules have reached the market as new antituberculosis agents. The mycobacterial cell wall biosynthesis is for a longstanding considered an important target for drug development. Particularly, in M. tuberculosis, the peptidoglycan crosslinks are predominantly formed by nonclassical bridges between the third residues of adjacent tetrapeptides. The responsible enzymes for these reactions are LD-transpeptidases (Ldts), for which M. tuberculosis has five paralogues. Although these enzymes are distinct from the penicillin-binding proteins (PBPs), they can also be inactivated by β-lactam antibiotics, but since M. tuberculosis has a chromosomal β-lactamase, most of the antibiotics of these classes can be degraded. Thus, to identify alternative scaffolds for the development of new antimicrobials against tuberculosis, we have integrated several fragment-based drug discovery techniques. Based on that, we identified and validated a number of small molecules that could be the starting point in the synthesis of more potent inhibitors against at least two Ldts from M. tuberculosis, LdtMt2 and LdtMt3. Eight identified molecules inhibited the Ldts activity in at least 20%, and three of them have antimycobacterial activity. The cell ultrastructural analysis suggested that one of the best compounds induced severe effects on the septum and cell wall morphologies, which corroborates our target-based approach to identifying new Ldts hits
Solving the probabilistic drone routing problem : searching for victims in the aftermath of disasters.
No full textSeveral major industrial disasters happen each year around the world. They usu-
ally involve limited accessibility, poor ground conditions, and toxic wastes. As a
consequence, this reduces the efficiency of humanitarian operations. In such a con-
text, flying drones may be a viable alternative: faster, no dependency on ground
conditions, and larger areas scanned. They are also better suited for following the
population and the crisis dynamic. For such a purpose, various issues have to be
addressed such as defining and optimizing the drone’s routes, their energy consump-
tion, choosing the relay points for recharging equipment, among others. In this study,
several additional features from existing works are considered: first, a probability
of identifying individuals is defined. Thus, each node can be scanned several times
in order to improve the observation. In addition, the nodes are prioritized accord-
ing to a given heatmap. The probabilistic drone routing problem (PDRP) consists of
finding a route, that is, a sequence of trips, for each drone such that the sum of the
expected number of identified individuals on all routes is maximized. Constraints on
energy consumption, collision avoidance and drone-base assignment are considered.
We propose a heuristic and metaheuristics based on the adaptive large neighborhood
search for the PDRP. The methods are tested on theoretical instances, as well as on
a case study of the Beirut Port explosion on August 4, 2020, in order to analyze the
performance of the proposed methods
Avaliação das manifestações patológicas de uma edificação industrial estruturada em aço : estudo de caso em uma planta de processamento mineral.
No full textPrograma de Pós-Graduação em Engenharia das Construções. Departamento de Engenharia Civil, Escola de Minas, Universidade Federal de Ouro Preto.O ambiente agressivo encontrado principalmente nas indústrias químicas e
petroquímicas tem demandado estudos de processos e produtos visando minimizar
os prejuízos causados pela corrosão dos equipamentos, visto que, as causas da
corrosão são inviáveis de serem eliminadas. Esse fenômeno é um importante fator
que deve ser levado em consideração na definição do material que será utilizado em
um projeto de construção ou de revitalização, em que devem ser analisadas as
condições de contorno de um processo específico no qual será aplicado. Com o
avanço da engenharia, encontram-se muitos tipos de aços disponíveis no mercado;
por conseguinte, é necessário investimento em pesquisas de campo voltadas à
Engenharia de Materiais com o intuito de definir que material é mais adequado para
determinado projeto ou manutenção das estruturas, apresentando um custo-
benefício relevante. Nesse contexto, o objetivo desta pesquisa é avaliar as
manifestações patológicas presentes nos elementos estruturais primários e
secundários de uma edificação industrial estruturada em aço. Justifica-se o trabalho
pela relevância de se ampliarem os estudos aplicados a manifestações patológicas
de estruturas de aço aplicadas em ambientes industriais agressivos,
especificamente, aqueles destinados a processamento mineral. A ação das
patologias encontradas no aço pode levar à necessidade de reparo emergencial ou
até mesmo, ao colapso da estrutura, o que reforça a importância do estudo no
fornecimento de subsídios para manutenção de edificações assim caracterizadas.
Como metodologia, é realizado um estudo de caso adotando-se uma edificação
estruturada em aço, construída na década de 1980, situada em um ambiente
industrial caracterizado como de média agressividade (C3), segundo a Norma ISO
12944-2. São identificadas as principais patologias existentes em quatro elevações,
sendo elas, térreo, segundo, terceiro e quarto níveis, onde localizam-se as estruturas
das vigas de rolamentos. Realizam-se inspeções in loco com registros fotográficos e
coleta de informações técnicas. No desenvolvimento do trabalho, as manifestações
patológicas são analisadas conforme a norma citada e classificadas com o auxílio da
ferramenta matriz de probabilidade e riscos, que possibilita recomendações com
prazos máximos para correções dos problemas de acordo com o nível de risco
identificado. São apresentados procedimentos de reparo e manutenção das
estruturas. Além disso, são mostrados os procedimentos implantados para a
recuperação de elementos afetados por manifestações patológicas que representam
alto risco à estrutura da edificação.The aggressive environment found mainly in the chemical and petrochemical
industries has required studies of processes and products aimed at minimizing the
damage caused by equipment corrosion, since the causes of corrosion are unviable
to be eliminated. This phenomenon is an important factor that must be taken into
consideration when defining the material that will be used in a construction or
revitalization project, in which the boundary conditions of a specific process in which
it will be applied must be analyzed. With the advancement of engineering, many
types of steel are available on the market; therefore, it is necessary to invest in field
research focused on Materials Engineering in order to define which material is most
suitable for a given project or maintenance of structures, presenting a relevant cost-
benefit. In this context, the objective of this research is to evaluate the pathological
manifestations present in the primary and secondary structural elements of an
industrial building structured in steel. The work is justified by the relevance of
expanding the studies applied to pathological manifestations of steel structures
applied in aggressive industrial environments, specifically those intended for mineral
processing. The action of pathologies found in steel can lead to the need for
emergency repairs or even to the collapse of the structure, which reinforces the
importance of the study in providing support for the maintenance of buildings
characterized in this way. As a methodology, a case study is carried out adopting a
steel-structured building, built in the 1980s, located in an industrial environment
characterized as medium aggressiveness (C3), according to ISO 12944-2. The main
pathologies existing in four elevations are identified, namely, the ground floor,
second, third and fourth levels, where the structures of the bearing beams are
located. On-site inspections are carried out with photographic records and collection
of technical information. During the work, pathological manifestations are analyzed
according to the standard and classified with the help of the probability and risk
matrix tool, which allows recommendations with maximum deadlines for correcting
the problems according to the level of risk identified. Procedures for repair and
maintenance of the structures are presented. In addition, the procedures
implemented for the recovery of elements affected by pathological manifestations
that represent a high risk to the structure of the building are shown
Processamento das ligas de Ni-Ti por meio da metalurgia do pó e seu comportamento mecânico e microestrutural.
No full textPrograma de Pós-Graduação em Ciências – Física de Materiais. Departamento de Física, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto.A liga Níquel-Titânio (NiTi) faz parte do grupo dos materiais inteligentes, destacando-se por
suas excelentes propriedades de memória de forma, superelasticidade, amortecimento e
biocompatibilidade. Esta liga é aplicada tanto em áreas tecnológicas quanto, principalmente,
nas áreas médicas e odontológicas. A utilização de processos de metalurgia do pó na fabricação
de produtos em ligas de titânio justifica-se pelas suas vantagens econômicas, tais como o alto
aproveitamento da matéria-prima, baixa energia de transformação em relação aos processos de
fusão, ótima tolerância dimensional, permitindo as mais variadas combinações e controle de
elementos químicos (ligas). Dessa forma, a Metalurgia do Pó se torna um processo interessante
no desenvolvimento de novos materiais, com a tendência em diminuir os custos no processo de
fabricação das ligas de Ni-Ti, alcançando propriedades mecânicas similares ao osso humano.
Este trabalho propõe uma análise microestrutural e das propriedades físicas e mecânicas da liga
NiTi processada via metalurgia do pó, combinando temperatura e tempo para produzir um
material adequado para o teste de viabilidade na biocompatibilidade no corpo humano.A
sinterização da liga foi realizada durante 24,36 e 48 horas a uma temperatura de 932 oC sem a
presença da fase líquida. Este estudo inclui técnicas de caracterização da propriedade mecânica
por meio da microdureza Vickers e, finalmente, a análise metalográfica com o auxílio de
Microscopia Óptica (MO) e Microscopia Eletrônica de Varredura (MEV).Observou-se que,
com o aumento do tempo de sinterização: a porosidade diminui, resultando em uma retração
volumétrica e aumento da densidade; Assim, a sinterização por 36 horas demonstrou ser a mais
ideal, podendo resultar em uma liga com as melhores propriedades de efeito de memória de
forma.The Nickel-Titanium (NiTi) alloy belongs to the group of smart materials, standing out for its
excellent shape memory properties, superelasticity, damping, and biocompatibility. This alloy
is used in both technological fields and, more importantly, in medical and dental areas. The use
of powder metallurgy processes in the production of titanium alloy products is justified by its
economic advantages, such as high raw material utilization, low energy transformation
compared to fusion processes, excellent dimensional tolerance, allowing for various
combinations and control of chemical elements (alloys). Therefore, powder metallurgy becomes
an interesting process in the development of new materials, with a tendency to reduce the
manufacturing costs of Ni-Ti alloys, achieving mechanical properties similar to human
bone.This study proposes a microstructural analysis and an examination of the physical and
mechanical properties of the NiTi alloy processed via powder metallurgy, combining
temperature and time to produce a material suitable for biocompatibility feasibility testing in
the human body.The alloy sintering was conducted over 24, 36, and 48 hours at a temperature
of 932°C without the presence of the liquid phase. This study includes characterization
techniques for mechanical properties using Vickers microhardness, and metallographic analysis
using Optical Microscopy (OM) and Scanning Electron Microscopy (SEM).It was observed that
with increased sintering time: porosity decreased, resulting in volumetric shrinkage and
increased density. Thus, sintering for 36 hours proved to be the most ideal, potentially resulting
in an alloy with the best shape memory effect properties
3E analyses of different blend fuels in an internal combustion engine.
No full textIn response to the escalating emphasis on sustainability across diverse sectors, this study addresses the imperative to combat environmental degradation through conscientious development. The primary focus is on assessing the feasibility of replacing fossil fuels with renewable alternatives in internal combustion engines (ICEs) equipped with direct fuel injection. The research employs energy and exergy analyses, coupled with economic analysis, to comprehensively evaluate
the performance of fuels and blends. Applying the Lotus Engine software, computational analyses are conducted, taking into account the specific geometry of the engine. Simulations explore different λ‐factors to identify optimal performance configurations for each fuel or blend. Noteworthy outcomes reveal that blends featuring green hydrogen yield remarkable improve ments, showing high torque (max. +11.5%), power (max. +14.35%), thermal efficiency (max. +3%), and exergy efficiency (max. +21.56%). These blends also demonstrate reduced operating costs (max. −10%), although with higher exergy losses, indicating areas for potential enhancement. Conversely, fuels containing ethanol show intermediate values between the blends and pure fuels. Consequently, this study effectively establishes the significance of these fuels in ICEs, supported by comprehensive energy, exergy, and economic analyses. The findings underscore the promising potential of renewable fuels as viable alternatives to fossil fuels, marking a substantial stride towards sustainable energy solutions and environmental preservation
Computational analysis and experimental validation of dialysis flow rate in central venous catheters.
No full textDespite a large number of studies on the favorable correlation between the higher dialysis dose and clinical efciency of hemodialysis treatment, the efect of the dialysis fow rate inside the catheter has been little investigated from the perspective of hemodynamic modifcations in the central venous access for hemodialysis. This study proposes the computational analy sis and an in vitro experimental validation of this model to assess hemodynamic behavior and the thrombogenic potential in central venous access for hemodialysis, using diferent fow rates in the central venous catheter (200, 250, 300, 350 and 400 mL/min). A mathematical model based on the Eulerian formulation was implemented in the solver subroutine to calcu late the linear platelet lysis index (PLIL). The pressure drop obtained from the computational and experimental models was compared to validate the computational model. The maximum percentage diference between these models was less than 13%. The fow rate of 250, 300 and 350 mL/min resulted in larger recirculation zones in the fow feld. It was concluded that, in general, shear stress and turbulence intensity increased quadratically with dialysis dose. The platelet lysis index increased with the dialysis fow rate and showed higher values at times associated with larger recirculation zones
Sleep deprivation induces genetic damage in mammalian cells : a systematic review.
No full textSleep is a natural biological state for reducing wakefulness, metabolism, and motor activity characterized by a reversible state and lack of responsiveness to some stimuli1,2. According to the American Academy of Sleep Medicine, the phenomenon can be classified into two stages: non-rapid eye movement (NREM – N1, N2, and N3) sleep stages and rapid eye movement (REM) sleep (R) stage3. Sleep has also been associated with functional brain connectivity and is required for processing information, energy conservation, and restoration4. Sleep deprivation occurs when an individual does not sleep well or even insufficient quantity or low quality of sleep, which leads to a decreasing performance and subsequent deterioration in general health5. This condition can impair several behavioral and biological activities, affecting cognition and mood, increasing fatigue, and decreasing vigor. This picture impairs speed, decision-making, and accuracy of motor tasks6. Although some environmental factors can interfere with the duration as well as the quality of sleep, it is also genetically controlled7. In particular, some studies have demonstrated that sleep deficiency leads to the injury to deoxyribonucleic acid (DNA) in mammalian cells, leading to cellular injury8-10. This is consistent with the idea that sleep loss could induce genotoxicity11. As a result, this systematic review was motivated to answer the following question: Can sleep deprivation induce genetic damage in mammalian cells
Resistance exercise training mitigates cardiac remodeling induced by a high-fat diet in rodents : a systematic review.
No full textBackground: Obesity is associated with the development of cardiovascular diseases and is a serious public health problem. In animal models, high-fat diet (HFD) feeding impairs cardiac structure and function and promotes oxidative stress and apoptosis. Resistance exercise training (RT), however, has been recommended as coadjutant in the treatment of cardiometabolic diseases, including obesity, because it increases energy expenditure and stimulates lipolysis.
Objective: In this systematic review, we aimed to assess the benefits of RT on the heart of rats and mice fed HFD.
Methods: Original studies were identified by searching PubMed, Scopus, and Embase databases from December 2007 to December 2022. This study was conducted in accordance with the criteria established by PRISMA and registered in PROSPERO (CRD42022369217). The risk of bias and methodological quality was evaluated by SYRCLE and CAMARADES, respectively. Eligible studies included original articles published in English that evaluated cardiac outcomes in rodents submitted to over 4 weeks of RT and controlled by a sedentary, HFD-fed control group (n = 5).
Results: The results showed that RT mitigates cardiac oxidative stress, inflammation, and endoplasmic reticulum stress. It also modifies the activity of structural remodeling markers, although it does not alter biometric parameters, histomorphometric parameters, or the contractile function of cardiomyocytes.
Conclusion: Our results indicate that RT partially counteracts the HFD-induced adverse cardiac remodeling by increasing the activity of structural remodeling markers; elevating mitochondrial biogenesis; reducing oxidative stress, inflammatory markers, and endoplasmic reticulum stress; and improving hemodynamic, anthropometric, and metabolic parameters