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A incompreensão do ciclo menstrual é um viés para o uso de recursos ergogênicos? : um estudo transversal.
No full textThe complex process of hormonal release and interaction of the Menstrual Cycle (MC) seems to impact the athlete's physical and psychological state. Objective: 1) investigate female athletes' understanding of MC, including its various phases and their potential effects on sports performance, 2) analyze the athletes' self-perception of sports performance during the different phases of MC and 3) identify possible ergogenic strategies (nutritional, mechanical, pharmacological, and/or psychological) adopted by athletes for alleviating premenstrual and menstrual symptoms in order to improve sports performance. Design: This exploratory cross-sectional study involved 105 competitive athletes, from 12 different sport modalities, from regional to international competitive level. Setting: Participants completed a survey assessing contraceptive use, knowledge regarding MC phases and perceptions of sports performance at different phases of MC as well as the adopted strategies to alleviate pre and menstrual symptoms to enhance sport performance. Results: Although 65.8% of the athletes reported knowing the MC phases, only 53.5% were able to identify them. Also, 60% of the athletes feel unmotivated or unwilling to exercise and 72.4% feel tired, indisposed, or self-reported worse sports performance during a certain phase of the MC, being follicular phase the most cited. Conclusions: The use of hormonal contraceptive methods, fatigue/discomfort and the number of weekly workouts seem to influence the use of nutritional aids. Competitive athletes have a limited understanding of MC, even considering that it has a detrimental effect on sports performance, especially during follicular phase. Feelings of tiredness, indisposition, or worse sports performance are the most common reasons for nutritional aids use.O complexo processo de liberação hormonal e interação do Ciclo Menstrual (MC) parece impactar o estado físico e psicológico do atleta. Objetivo: 1) investigar a compreensão do MC por atletas femininos, incluindo suas várias fases e seus efeitos potenciais sobre o desempenho esportivo; 2) analisar a autopercepção do desempenho esportivo por atletas durante as diferentes fases do MC; e 3) identificar possíveis estratégias ergogénicas (nutricionais, mecânicas, farmacológicas e/ou psicológicas) adotadas por atletas para aliviar os sintomas pré-menstruais e menstruais, a fim de melhorar o desempenho esportivo. Design: Este estudo transversal exploratório envolveu 105 atletas competitivos, de 12 modalidades diferentes de desporto, de nível regional a nível competitivo internacional. Configuração: Os participantes completaram uma pesquisa avaliando o uso de contracetivos, o conhecimento sobre as fases da MC e as perceções do desempenho esportivo em diferentes fases da MC, bem como as estratégias adotadas para aliviar os sintomas pré e menstruais para melhorar o desempenho esportivo. Resultados: Embora 65,8% dos atletas tenham relatado conhecer as fases do MC, apenas 53,5% conseguiram identificá-los. Além disso, 60% dos atletas se sentem desmotivados ou não dispostos a se exercitar e 72,4% se sentem cansados, indispostos ou autorreferidos pior desempenho esportivo durante uma determinada fase do MC, sendo a fase folicular a mais citada. Conclusões: O uso de métodos contracetivos hormonais, fadiga / desconforto e o número de exercícios semanais parecem influenciar o uso de ajudas nutricionais. Atletas competitivos têm um entendimento limitado do MC, mesmo considerando que ele tem um efeito prejudicial no desempenho esportivo, especialmente durante a fase folicular. Sentimentos de cansaço, indisposição ou pior desempenho esportivo são as razões mais comuns para o uso de ajudas nutricionais
Hydrogen as renewable energy source in the mining industry.
No full textNa indústria de mineração, os equipamentos desempenham papel primordial na produção e operação, mas consomem quantidades significativas de energia, com destaque para os motores a diesel. Nas operações mineiras, esses motores são amplamente empregados devido à versatilidade, capacidade de carga e adaptabilidade a várias condições de terreno. No entanto, é importante observar também que apresentam alto consumo de óleo diesel e contribuem substancialmente para as emissões de gases de efeito estufa. Essa realidade ressalta a necessidade de explorar alternativas de energia renovável, como o hidrogênio verde, para reduzir o impacto ambiental e promover a sustentabilidade nas operações de mineração. Este artigo apresenta discussão do consumo de energia na mineração, das tecnologias de produção do hidrogênio, as vantagens em utilizar o hidrogênio em motores diesel e os desafios de produção, armazenamento e fornecimento. Destaca-se o hidrogênio verde, livre de carbono, alternativa emergente na descarbonização das minas.In the mining industry, equipment plays a key role in production and operation, but consumes significant amounts of energy, especially diesel engines. In mining operations, these engines are widely used due to their versatility, load capacity and adaptability to various terrain conditions. However, it is also important to note that they consume a lot of diesel fuel and contribute substantially to greenhouse gas emissions. This reality highlights the need to explore renewable energy alternatives, such as green hydrogen, to reduce environmental impact and promote sustainability in mining operations. This article discusses energy consumption in mining, hydrogen production technologies, the advantages of using hydrogen in diesel engines and the challenges of production, storage, and supply. It highlights green, carbon-free hydrogen, an emerging alternative for decarbonizing mines
Recycled Kambara reactor slag powder as a sustainable stabilizer for clayey soils in road construction.
No full textSteel manufacturers around the world are looking for ways to produce higher quality, lower-sulfur steel. This requires an additional desulfurization step using the Kambara reactor (KR) during steel production. As a side effect, the Kambara reactor’s slag processing generates emissions that are captured and concentrated in dust collectors such as bag filters, reducing overall air pollution. While the use of KR slag has gained attention in the road material industry for improving pavement design performance, the reuse potential of KR slag powder (KRSP), collected by special bag filters, remains underexplored. This study investigates the chemical composition, physical properties, and mechanical characteristics of clayey soil mixed with KRSP. To assess the byproduct’s ability to stabilize this soil, laboratory experiments were conducted on raw materials and soil mixed with 3% and 5% KRSP. The results reveal that the specific gravity of KRSP (2.23 g/cm3) is lower than that of granulated KR slag. X-ray fluorescence analysis detected no iron (Fe) in its composition, and the percentage of calcium oxide (CaO) was below 40%. Portland cement (Ca(OH)2) was identified as the main mineral present through X-ray diffraction analysis, and brucite (Mg(OH)2) as the minor mineral. The addition of 3% and 5% KRSP to clayey soil resulted in a significant increase in California Bearing Ratio (CBR) values (from 13 to 42% and 41%, respectively) after only 4 days of curing. Unconfined compressive strength values obtained for the 3% and 5% KRSP mixtures were 1.25 MPa and 0.95 MPa, respectively, after 7 days of curing. Atterberg limits, particle size distribution, and expansion tests reinforced the results, showing compliance with the requirements for first-class subbase materials. This finding demonstrates that KR desulfurization dust collector powder has the potential to be used as an environmentally friendly stabilizing agent, contributing to improved waste management in the steel industry
Holographic ricci dark energy in nonconservative unimodular gravity.
No full textThe structure of unimodular gravity (UG) is invariant to a subclass of diffeomorphism, the transverse diffeomorphism, due to the unimodular condition (√−g = ϵ = cte). Consequently, there is a freedom to define how the conservation laws of the energy-momentum tensor in unimodular gravity in the cosmological context. One of the main characteristics of the complete system of equations that describe cosmological dynamics in UG is that they form an underdetermined system if the usual conservation law of the energy-momentum tensor is not used in your structure, that is, it is necessary to insert extra information into the system to solve the complete set of equations. In this article, we propose the construction of a background cosmological model based on the description of a holographic dark energy component with a cutoff of the order of Ricci scalar in non-conservative UG. Although this choice is indeed a new addition of information to the cosmological system, the complete set of equations remains underdetermined, however, the new feature of this cosmologi cal model is the appearance of an interaction between matter and dark energy. Indeed, this is a well-known characteristic of cosmological models in which we have holographic dark energy density. Consequently, we propose an ansatz to the interaction term Q = βHρm, and obtain the cosmo logical parameters of our model. We found a viable universe model with similar characteristics to the ΛCDM model. We performed statistical analysis of the background model using the ”Cosmic Chronometer” (CC) data for H(z), and obtain as a result using Akaike Information Criterion (AIC),
and the Bayesian Information Criterion (BIC) as model selection criteria that ΛCDM prevails as the best model. However, the proposed model is competitive when compared to the cosmological model ωCDM
Microconcretos autoadensáveis contendo resíduo de rocha ornamental e resíduo de poliestireno expandido : influência das relações filler/cimento e agregados leves/convencionais.
No full textEco-efficient self-compacting micro concretes with partial replacement of Portland cement by ornamental stone waste (OSW) and replacement of conventional aggregates by expanded polystyrene waste were addressed in this study. A base mixture was obtained using a particle packing method, and replacement fractions followed a second-order composite experimental design. The mixtures’ rheological, physical, mechanical and eco-efficiency parameters were evaluated and discussed. As expected, the incorporation of residues reduced the mechanical strength, and mixtures with high incorporation of lightweight aggregates tended to segregate. However, OSW has been shown to increase workability and decrease viscosity, contributing to control segregation due to the reduced amount of water required without impairing the fluidity of the mix. At the same time, the lightweight aggregate decreased both the density of the mixtures and the viscosity. The interaction of the residue with the lightweight aggregate proved promising in obtaining more eco-efficient lightweight microconcretes.Foram abordados neste estudo micro concretos autoadensáveis ecoeficientes com substituição parcial do cimento Portland por resíduo de rochas ornamentais (do inglês ornamental stone waste - OSW) e substituição dos agregados convencionais por resíduo de poliestireno expandido. A dosagem foi feita utilizando metodologia de empacotamento de partículas, e as frações de substituição seguiram um projeto experimental estatístico composto de segunda ordem. Foram avaliados e discutidos os parâmetros reológicos, físicos, mecânicos e de ecoeficiência das misturas. Como esperado, a incorporação dos resíduos diminuiu a resistência mecânica, e as misturas com elevadas incorporações de agregados leves apresentaram tendência a segregação. Entretanto, a adição do resíduo OSW demonstrou aumentar a trabalhabilidade e diminuir a viscosidade, contribuindo para controlar a segregação devido à redução no consumo de água necessário sem prejudicar a fluidez da mistura. Ao mesmo tempo, o agregado leve diminuiu tanto a densidade das misturas quanto a viscosidade. A interação do resíduo com o agregado leve se mostrou promissora na obtenção de microconcretos leves mais ecoeficientes
Direitos sexuais e direitos reprodutivos das mulheres com deficiência no Brasil : análise das autonomias a partir das perspectivas biojurídica e decolonial.
No full textPrograma de Pós-Graduação em Direito. Departamento de Direito, Escola de Direito, Turismo e Museologia, Universidade Federal de Ouro Preto.A pesquisa tem como tema os direitos sexuais e os direitos reprodutivos das mulheres com
deficiência no Brasil, a partir da análise das autonomias em perspectiva biojurídica e decolonial.
Como problema de pesquisa têm-se o questionamento se a estrutura jurídica posta contempla
as autonomias das mulheres com deficiência em perspectiva biojurídica e decolonial. Objetiva-
se estudar criticamente os direitos sexuais e os direitos reprodutivos garantidos às mulheres
com deficiência brasileiras, a partir da perspectiva biojurídica das autonomias sob a ótica da
decolonialidade. O marco teórico do trabalho é a noção teórica biojurídica e decolonial de
autonomias, em acepção plural, construída a partir de Iara Antunes de Souza e Natália de Souza
Lisbôa (2016; 2020), em vista da qual considera-se as diferentes possibilidades de expressão de
vontade discernida, a partir do reconhecimento de diversidades, de vulnerabilidades e de
interseccionalidades. A metodologia se operacionaliza por meio da vertente metodológica
jurídico-social; dos tipos genéricos de pesquisa jurídico-compreensivo e jurídico-propositivo;
em pesquisa do gênero teórico com caráter interdisciplinar, afeta ao Biodireito e à epistemologia
decolonial. Entende-se a decolonialidade como nova epistemologia pela qual se realiza releitura
do instituto jurídico da autonomia biojurídica na busca da garantia de direitos a pessoas
invisibilizadas socialmente, quais sejam mulheres com deficiência, a partir do reconhecimento
das diversidades, das vulnerabilidades e das interseccionalidades, o que justifica a adesão do
trabalho a linha de pesquisa “Novos Direitos, Desenvolvimento e Novas Epistemologias”. A
hipótese de pesquisa é a de que o modelo em que se estrutura as garantias jurídicas de direitos
sexuais e direitos reprodutivos de mulheres com deficiência no Brasil reproduz a lógica
colonial, que exclui e invisibiliza pessoas e não contempla as autonomias diversas das mulheres
com deficiência. Conclui-se que as autonomias - em acepção plural - das mulheres com
deficiência não são contempladas pela estrutura júridica posta, que reproduz colonialidades, e
assim não contempla as diversas possibilidades de exercício de autonomias das mulheres com
deficiência.The research has as its theme sexual rights and reproductive rights of women with disabilities
in Brazil, based on the analysis of autonomies in a biojuridical and decolonial perspective. As
a research problem, questions arise as to whether the proposed legal structure contemplates
autonomies in a decolonial biolegal perspective. The objective is to critically study the sexual
and reproductive rights guaranteed to Brazilian women with disabilities, from the biojuridical
perspective of autonomies from the perspective of decoloniality. The theoretical framework of
the work is the biolegal and decolonial notion of autonomies, in a plural sense, constructed by
Iara Antunes de Souza and Natália de Souza Lisbôa (2016; 2020), which considers the different
possibilities of expressing discerned will, based on the recognition of diversities, vulnerabilities
and intersectionalities. The methodology is operationalized through the legal-social
methodological strand; the generic types of legal-comprehensive and legal-propositional
research; in research of the theoretical genre with an interdisciplinary character, affecting
Biolaw and decolonial epistemology. Decoloniality is understood as a new epistemology that
provides a reinterpretation of the legal institute of bio-juridical autonomy is reread in order to
guarantee the rights of socially invisible people, such as women with disabilities, based on the
recognition of diversity, vulnerability and intersectionality, which justifies the work's adherence
to the research line "New Rights, Development and New Epistemologies". The research
hypothesis is that the model which structures the legal guarantees of sexual rights and
reproductive rights of women with disabilities in Brazil reproduces the colonial logic, which
excludes and invisibilizes people and does not take into account the diverse autonomies of
women with disabilities. The conclusion is that the autonomies - in the plural sense - of women
with disabilities are not taken into account by the legal structure in place, which reproduces
colonialities and thus does not take into account the diverse possibilities for women with
disabilities to exercise their autonomies
Temperament of psittaciformes : a systematic review.
No full textThe study of temperament of the order Psittaciformes has been expanding over the past decades due to the publication of papers investigating individual differences in various species. This review aimed to integrate studies on the temperament of Psittaciformes in a systematized manner, focusing on methodological aspects. It also aimed to reveal the main dimensions of temperament described for these species, identify possible gaps and suggest new themes that deserve the scientific community’s attention. The Preferred Reporting Items for Sys- tematic Reviews and Meta-Analyses (PRISMA) methodology was followed, and the search was conducted using Population, Intervention, and Context (PICo) terms. Three databases were used (Scopus, Web of Science, and CABI), resulting in a total of 24 publications included. The most used term to express consistent interindividual behavioral differences was ‘personality’ (11; 45.83 %), followed by ‘temperament’ (8; 33.33 %), without a clear distinction of both in this research field. Studies on temperament were conducted within the families Psittacidae (18; 75 %), Psittaculidae (4; 16.67 %) and Cacatuidae (2; 8.33 %), with the genus Amazona being the most investigated (14; 58.33 %). Regarding context, all papers used animals under human care (kept in captive environments). In total, 22 temperament dimensions were compiled, with ‘boldness’ (or ‘shy-bold’ axis or ‘shyness-boldness’), ‘neophobia/neophilia’, ‘exploration’, and ‘vigilance’ being the most common. Quantitative methods of assessment (coding) were more commonly applied, being used in 19 (79.17 %) publications, compared to qualitative ones (rating methods). Among the factors related to temperament, pre- and post-release behavior was the most investigated (5; 20.83 %). We could conclude that studies were concentrated on a few taxonomic groups, highlighting the need to broaden the subjects studied, including other families, genera, and species. Furthermore, it would be interesting to expand the temperament evaluations into wild contexts to better un- derstand consistent interindividual differences in parrots’ natural behaviors. More efforts should be directed towards methodological and conceptual standardization, in addition to applying temporal consistency analyses. Some additional gaps that have not been studied yet include research on the genetic basis, as well as morpho- physiological and neuroendocrine mechanisms underlying temperament in Psittaciformes
Gastagus’ performance in Cabo Verde, a report of experience in the extension.
No full textNo presente trabalho, fez-se uma análise das ações realizadas em um projeto de curta duração realizado nos municípios de Assomada e Porto Rincão em Cabo Verde em parceria com as instituições AMA (Associação Mulheres em Ação) e Aldeias Infantis S.O.S. A equipe do GASTagus, em parceria com a AMA, organizou e realizou de uma colónia de férias destinada às crianças e jovens de três bairros da cidade de Assomada. Com as Aldeias Infantis S.O.S o grupo atuou na cidade de Porto Rincão, dando formações a líderes comunitarios objetivando a criação de uma associação conjunta entre quatro grupos locais: Peixeiras, Pescadores, Comite Infantojuvenil e Associação de estudantes universitários. Como resultado dos projetos notou-se o desenvolvimento de todos beneficiados, os jovens atendidos em Assomada e os líderes comunitários de Porto Rincão demonstraram ao decorrer do projeto maior interesse pelos estudos e preocupação com a comunidade e se tornaram multiplicadores em busca da melhoria das condições de vida nessas regiões.In the present work, an analysis was made of the actions carried out in a short-term project carried out in the municipalities of Assomada and Porto Rincão in Cape Verde in partnership with the institutions Associação Mulheres em Ação (AMA) and Aldeias Infantis S.O.S. The GASTagus team, in partnership with AMA, organized and held a summer camp for children and young people from three neighborhoods in the city of Assomada. With the SOS Children's Villages, the group worked in the city of Porto Rincão, providing training to community leaders with the aim of creating a joint association between four local groups: Fishmongers, Fishermen Children's
Committee and the University Students' Association. As a result of the projects, the development of all beneficiaries was noted, the young people served in Assomada and the community leaders of Porto Rincão demonstrated, during the project, greater interest in studies and concern for the community and became multipliers in the search for improving the life conditions in these regions
Otimização de vigas em perfis formados a frio utilizando algoritmos genéticos.
No full textPrograma de Pós-Graduação em Engenharia Civil. Departamento de Engenharia Civil, Escola de Minas, Universidade Federal de Ouro Preto.Elementos estruturais em perfil formado a frio são fabricados a partir do dobramento
de chapas metálicas esbeltas, conferindo às obras civis a redução do peso estrutural
e facilidades no transporte e armazenagem. Esses perfis possuem diversas
aplicações na construção civil, como os sistemas de armazenagem industrial. Por
serem fabricados com chapas finas, esses elementos estruturais estão sujeitos à
fenômenos de instabilidade que podem reduzir a resistência. As análises de
estabilidade elástica necessárias à avaliação dos perfis formados a frio são
executadas por métodos que fornecem a curva de assinatura característica de cada
seção. Alguns programas de análise, como o CUFSM, possuem código aberto, o que
facilita a integração a algoritmos de otimização, como o Algoritmo Genético. No
processo de otimização estrutural de vigas, é importante que se obtenha soluções que
possibilite a redução da área de seção transversal e deslocamento sem
comprometimento da resistência do elemento. O presente estudo teve como objetivo
a obtenção de seções transversais de vigas em perfil formado a frio otimizadas para
sistemas de armazenagem industrial porta-pallets. Os perfis otimizados foram obtidos
a partir da aplicação de funções objetivo e resolução via Algoritmo Genético. O cálculo
do momento fletor resistente característico foi realizado de acordo com o Método da
Resistência Direta da ABNT NBR 14762/2010, com cargas críticas definidas por
análise de estabilidade elástica com o CUFSM, em uma rotina de análise
implementada pela plataforma MATLAB. Quatro seções foram estudadas, verificando
o conjunto ótimo de altura, largura e enrijecedores que atendiam aos objetivos
definidos pelas funções, assumindo valores de referência de uma seção retangular
tipicamente utilizada. Os resultados demonstram a possibilidade de fabricação de
vigas em perfil formado a frio que consumam menos material e/ou que possuam
melhor momento de inércia em relação à seção de referência, sem o
comprometimento da resistência do elemento estrutural. Conclui-se que algumas
combinações de enrijecedores que tornam as seções mais simples são mais eficientes
que soluções complexas.Cold-formed structural elements are made by folding thin sheets of metal, reducing the
weight of structures and making them easier to transport and store. These profiles
have various civil engineering applications, such as industrial storage systems.
Because they are made from thin sheets, these structural elements are subject to
instability phenomena that can reduce their strength. The elastic stability analyses
required to evaluate cold-formed profiles are performed using methods that provide
the characteristic signature curve of each section. Some analysis programs, such as
CUFSM, are open source, which facilitates integration with optimization algorithms
such as the Genetic Algorithm. In the process of structural optimization of beams, it is
important to obtain solutions that reduce the cross-sectional area and displacement
without compromising the strength of the element. The objective of this study was to
obtain optimized cross-sections of cold-formed beams for industrial pallet storage
systems. The optimized cross-sections were obtained by applying objective functions
and solving them using the Genetic Algorithm. The calculation of the characteristic
bending moment was carried out according to the direct resistance method of ABNT
NBR 14762/2010, with critical loads defined by the elastic stability analysis with
CUFSM, in an analysis routine implemented by the MATLAB platform. Four sections
were studied, checking the optimal set of height, width and stiffeners that meet the
objectives defined by the functions, assuming reference values of a typically used
rectangular section. The results show that it is possible to produce cold-formed beams
that consume less material and/or have a better moment of inertia with respect to the
reference section, without compromising the strength of the structural element. It is
concluded that some combinations of stiffeners that make the sections simpler are
more efficient than complex solutions
Metabolic consequences of interesterified palm oil and PCB-126 co-exposure in C57BL/6 mice.
No full textMetabolic dysfunction-associated steatotic liver disease (MASLD) is defined as morphofunctional changes in the liver. Studies have shown that Westernized eating patterns and environmental pollutants can directly induce the development of MASLD. This study evaluates the effect of co-exposure to interesterified palm oil (IPO) and 3,3′,4,4′,5-pentachlorobiphenyl (PCB-126) on the progression of MASLD in an animal model. C57BL/6 mice were fed IPO and co-exposed to PCB-126 for ten weeks. The co-exposure led to an imbalance in carbohydrate metabolism, increased systemic inflammation markers, and morphofunctional changes in the liver. These liver changes included the presence of inflammatory cells, fibrosis, alterations in aspartate transaminase (AST) and alanine transaminase (ALT) enzymes, and imbalance in gene expression related to fatty acid β-oxidation, de novo lipogenesis, mitochondrial dynamics, and endoplasmic reticulum stress. Separate exposures to IPO and PCB-126 affected metabolism and MASLD progression. Nutritional and lifestyle factors may potentiate the onset and severity of MASLD