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Otimização topológica de vigas mistas aço-concreto com interação parcial.
No full textPrograma de Pós-Graduação em Engenharia Civil. Departamento de Engenharia Civil, Escola de Minas, Universidade Federal de Ouro Preto.As seções mistas aço-concreto estão cada vez mais presentes nas obras de
Engenharia Civil. A associação entre a laje de concreto e o perfil metálico é feita
por meio de conectores de cisalhamento, os quais permitem um deslocamento
relativo entre os componentes. No contexto de estruturas mistas, esse fenômeno
é chamado de interação parcial, e, na prática, apresenta um comportamento
estrutural diferente de um sistema composto por dois elementos rigidamente
conectados. Nesta tese, é utilizado o Método dos Elementos Finitos para a
simulação computacional de vigas mistas aço-concreto com interação parcial.
Nesse sentido, elementos de interface são responsáveis não só pela definição
da rigidez da conexão deformável, como também pelo acoplamento entre
elementos planos de casca de quatro nós, utilizados na discretização da laje
de concreto, e elementos triangulares de três e de seis nós em estado plano
de tensões, utilizados na modelagem do perfil de aço. As análises também
incorporam um modelo constitutivo capaz de representar as não-linearidades
do aço e do concreto. Em uma segunda etapa, o algoritmo evolucionário
conhecido como Evolutionary Structural Optimization (ESO) é adaptado para
utilizar esse modelo numérico no processo de otimização topológica da viga
mista. São desenvolvidas duas variações distintas, a saber: ESO-VM1 e ESO-
VM2. Tais métodos promovem a retirada convencional de elementos da malha,
isto é, atribuindo-se uma rigidez reduzida ao elemento ou, alternativamente,
promovendo sua retirada efetiva e o consequente remalhamento da estrutura a
cada iteração. Adicionalmente, a não-linearidade física pode ser contemplada
no processo evolucionário. Em última análise, são apresentados exemplos que
permitem não apenas validar as implementações, mas também estabelecer
comparações entre as diferentes estratégias. Topologias ótimas conduzem a
uma configuração treliçada para o perfil e a uma largura mínima previamente
estipulada para a laje de concreto. No caso não-linear é possível, ainda, otimizar
a taxa de armadura da laje de concreto.Composite steel-concrete sections are increasingly present in Civil En-
gineering buildings.The association between the concrete slab and the steel
profile is made through shear connectors, which allows for relative displace-
ment between the components. In the context of composite structures, this
phenomenon is referred to as partial interaction, and, in practice, exhibits a
structural behavior that differs significantly from that of a system composed
of two rigidly connected elements. In this thesis, the Finite Element Method is
used for the computational simulation of composite steel-concrete beams with
deformable connection. In this regard, interface elements are responsible not
only for defining the stiffness of the deformable connection but also for the
coupling between four-node shell elements, used in the discretization of the
concrete slab, and triangular elements with three and six nodes under plane
stress conditions, the latter two used in modeling the steel profile. The analyses
also consider a constitutive model capable of representing the nonlinearities of
both steel and concrete. In a second phase, the evolutionary algorithm known
as Evolutionary Structural Optimization (ESO) is adapted to use this numeri-
cal model in the topological optimization process of the composite beam. Two
distinct variations are developed, namely: ESO-VM1 and ESO-VM2. These
methods consider the conventional removal of elements from the mesh, that
is, by assigning reduced stiffness to the element or, alternatively, promoting
its effective removal and the consequent remeshing of the structure at each
iteration. Furthermore, physical nonlinearity can be incorporated into the evo-
lutionary process. Finally, examples are presented that not only validate the
implementations but also establish comparisons between the different strate-
gies. Optimal topologies result in a truss configuration for the profile and a
previously specified minimum width for the concrete slab. In the nonlinear
case, it is also possible to optimize the reinforcement ratio of the concrete
slab
Affordance of conciliation : increasing the social impact of hybrid organizations.
No full textPurpose – Hybrid organizations offer an innovative approach to promote social impact. However, hybrids face the challenge of reconciling the dual mission (social/financial). The purpose is to understand how hybrids and information and communication technologies (ICT) interact, unveiling opportunities ICT offers for hybrids regarding the dual mission. Design/methodology/approach – We used affordance theory and adopted a predominantly inductive approach inspired by the so-called “Gioia template.” The research design was based on semi-structured interviews with entrepreneurs, specialists, and people working in institutes, foundations, and accelerators, i.e. social actors operating in the hybrid organizational ecosystem in Brazil. Findings – Our findings suggest that the affordances of the relationship between organizational and ICT resources act as facilitators. A theoretical contribution is conceptualizing “affordance of conciliation,” indicating how ICT resources might facilitate achieving social/financial goals, thus minimizing efforts to reconcile mission duality. Furthermore, we list categories and aggregate dimensions and elucidate how results aligned with goals are generated through the process-based model. We show that ICT has a significant role in helping hybrids overcome challenges. Originality/value – Our results extend affordance theory with theoretical and practical implications. We highlight fundamental components that contribute to proposing the new concept of “affordance of conciliation.” We contribute to information systems literature by better understanding the social interactions between ICT and hybrids. Finally, we help hybrids understand the support of ICT resources to fulfill their dual mission
An effective strategy for stacking and reclaiming iron ore piles.
No full textThis study examines the impact of the size of homogenized ore stockpiles on the feed rate of concentration-ore plants and the inter-pile grade variability. An integrated simulation optimiza tion tool is used to incorporate the dynamic characteristics of this process. Therefore, applying the discrete event simulation technique in this study made it possible to analyze the losses due to the lack of homogenized piles in the ore yard. Three scenarios from a Brazilian mine company were explored. The results report an ore production gain of 5.57% of the scenario with the smallest ore pile size compared with a scenario with the largest ore pile siz
Turismo criativo e de base comunitária na perspectiva do desenvolvimento sociocultural local : um estudo no distrito criativo de Passagem de Mariana, Minas Gerais.
No full textPrograma de Pós-Graduação em Turismo e Patrimônio. Departamento de Turismo, Escola de Direito, Turismo e Museologia, Universidade Federal de Ouro Preto.O objetivo geral deste estudo é investigar a associação dos conceitos Turismo Criativo (TC),
Turismo de Base Comunitária (TBC) e Distritos Criativos e sua relação com o desenvolvimento
sociocultural local, tomando o Distrito Criativo de Passagem (DCP), em Mariana-MG, como
caso de estudo. Os objetivos específicos são: (1) investigar a associação dos conceitos de TC,
TBC e Distritos Criativos, através de uma revisão sistemática da literatura, identificando
categorias analíticas que compõem uma percepção teórico-empírica das congruências entre o
TC e o TBC; (2) explorar a aplicabilidade do TC e TBC em sua relação com o desenvolvimento
sociocultural local a partir do DCP. Utilizando uma abordagem qualitativa e exploratória, o
artigo realiza revisão bibliográfica, análise documental e observação não participante. Essas
metodologias permitiram uma compreensão dos processos interconectados, oferecendo
apontamentos relevantes para o desenvolvimento social e cultural do distrito. Ao abordar as
temáticas do TC, TBC e Distritos Criativos, este estudo contribuiu para uma maior
compreensão dos fatores que impulsionam o desenvolvimento sociocultural local. O estudo
ofereceu insights práticos e teóricos para aprimorar a gestão de destinos turísticos criativos,
bem como promover uma visão mais inclusiva e sustentável do turismo nas comunidades locais.
A análise revelou convergências significativas entre o TC e o TBC, que foram identificadas e
examinadas para desenvolvermos uma proposta teórico-empírica que enfatiza a abordagem
congruente de ambos os conceitos em relação à participação social, preservação cultural,
desenvolvimento econômico, fomento criativo, sustentabilidade, aprendizagem, integração e
desenvolvimento local. A referência desta proposta teórica no DCP foi exemplificada,
demonstrando viabilidade prática e benefícios locais.The general objective of this study is to investigate the association of the concepts of Creative
Tourism (CT), Community-Based Tourism (CBT) and Creative Districts and their relationship
with local sociocultural development, taking the Creative District of Passagem (DCP) in
Mariana-MG, as a case study. The specific objectives are: (1) to investigate the association of
the concepts of CT, CBT and Creative Districts through a systematic review of the literature,
identifying analytical categories that make up a theoretical-empirical perception of the
congruencies between CT and CBT; (2) explore the applicability of CT and CBT in their
relationship with local sociocultural development based on the DCP. Using a qualitative and
exploratory approach, the article performs a literature review, document analysis and non-
participant observation. These methodologies allowed an understanding of interconnected
processes, offering relevant notes for the social and cultural development of the district. By
addressing the themes of CT, CBT and Creative Districts, this study contributed to a greater
understanding of the factors that drive local sociocultural development. The study offered
practical and theoretical insights to improve the management of creative tourist destinations
and promote a more inclusive and sustainable vision of tourism in local communities. The
analysis revealed significant convergences between CT and CBT, which were identified and
examined to develop a theoretical-empirical proposal that emphasizes the congruent approach
of both concepts about social participation, cultural preservation, economic development,
creative promotion, sustainability, learning, integration and local development. The reference
of this theoretical proposal in the DCP was exemplified, demonstrating practical feasibility and
local benefits
Consumption of processed meat but not red meat is associated with the incidence of hypertension : ELSA-Brasil cohort.
No full textObjectives: To verify the association between the consumption of red and processed meats and the incidence of hypertension in participants of the Longitudinal Study of Adult Health.
Methods: This was a cohort with data from the baseline (2008–2010) and second wave (2012–2014) with 8,089 public workers of both sexes and different racial groups, with mean age of 49 ± 8 years (35–74 years old). Meat consumption (g/d) was estimated using a food frequency questionnaire and was divided into consumption tertiles. Hypertension was defined as systolic blood pressure ≥140 mm Hg and/or diastolic ≥90 mm Hg and/or antihypertensive medication. Cox proportional hazards models were used to estimate adjusted Hazard Ration (HRs) and 95% confidence interval (CI) for incident hypertension.
Results: A total of 1186 incident cases of hypertension were identified. Even adjusting for confounders, such as urinary Na/K (sodium/potassium) ratio and BMI (body mass index), participants in the second (HR:1.19; 95% CI 1.03–1.30) and third (HR:1.30; 95% CI:1.11–1.53) tertile of processed meat consumption had a higher risk of developing hypertension than those in the first tertile. We did not find a significant association between red meat consumption and hypertension.
Conclusions: The increased risk of developing hypertension is associated with moderate and high consumption of processed meats but not with consumption of red meat
Acompanhamento odontológico da gestante nas equipes de saúde bucal do município de Belo Horizonte - MG.
No full textPrograma de Pós-Graduação em Saúde da Família. Departamento de Medicina de Família, Saúde Mental e Coletiva, Escola de Medicina, Universidade Federal de Ouro Preto.Esta pesquisa teve como objetivo principal a descrição e a análise do
indicador de proporção de gestantes com atendimento odontológico realizado - o
indicador três do Programa Previne Brasil - no município de Belo Horizonte, Estado
de Minas Gerais (MG), Brasil. Analisou-se, ainda, se a adesão ao pré-natal e os
fatores sociodemográficos poderiam estar associados à realização dessa consulta.
Trata-se de um estudo transversal de abordagem descritiva e analítica utilizando
dados secundários relacionados ao serviço de atenção odontológica das gestantes,
compreendendo os três quadrimestres de 2022. Observou-se que, durante o período
de análise, os indicadores do município permaneceram abaixo da meta estipulada,
que era de 60%, ficando respectivamente em 26%, 25% e 30% para os 3
quadrimestres de 2022. As gestantes que se declararam negras (OR: 1,12 / IC 95%:
1,04 - 1,20), que residiam em áreas com IVS-BH de médio risco (OR: 1,17 / IC 95%:
1,04 - 1,33) ou que residiam em áreas com IVS-BH de elevado risco (OR: 1,24 / IC
95%: 1,09 - 1,40) possuíram maiores chances de realizarem suas consultas
odontológicas. Contrariamente, aquelas que não realizaram as seis consultas de
pré-natal (OR: 0,49 / IC 95%: 0,46 - 0,53), que não recebiam bolsa família (OR: 0,84
/ IC 95%: 0,73 - 0,97) ou com faixa etária entre 20-34 anos (OR: 0,88 / IC 95%: 0,80
- 0,97) possuíram menos chances de realizá-las. Elaborou-se um Relatório Técnico
Conclusivo, com a finalidade de informar à coordenação de saúde bucal do
município, sobre os principais resultados e conclusões alcançados. Ao se descrever
o indicador de proporção de gestantes com atendimento odontológico realizado, em
Belo Horizonte, nos três quadrimestres de 2022, pode-se afirmar que as gestantes
tiveram acesso às consultas, entretanto teria sido necessário ampliá-lo, para que
todas elas pudessem acessar o serviço ou, ao menos, 60% delas, parâmetro
considerado como meta a ser atingida para fins de pagamento por desempenho.
Ficou evidente a necessidade de um cadastro mais eficiente, para que se conheça o
perfil de utilização do serviço e as necessidades das usuárias, incluindo as
condições sociodemográficas analisadas. Também é importante o reconhecimento
de grupos etnicamente minoritários presentes no território para que se reconheçam
suas particularidades e peculiaridades. Este Trabalho de Conclusão de Mestrado é
fruto do Programa de Pós-Graduação stricto sensu Mestrado Profissional em Saúde
da família (PROFSAÚDE).The main objective of this study was to describe and analyze the indicator of
the proportion of pregnant women who received dental care - indicator 3 of the
Previne Brasil Program - in the city of Belo Horizonte, State of Minas Gerais (MG),
Brazil. It was also analyzed whether adherence to prenatal care and
sociodemographic factors could be associated with the performance of this
consultation. This is a cross-sectional study with a descriptive and analytical
approach using secondary data related to the dental care service for pregnant
women, covering the three four-month periods of 2022. It was observed that, during
the analysis period, the municipality's indicators remained below the stipulated target,
which was 60%, remaining respectively at 26%, 25% and 30% for the three four-
month periods of 2022. Pregnant women who declared themselves black (OR: 1.12 /
95% CI: 1.04 - 1.20), who lived in areas with medium-risk IVS-BH (OR: 1.17 / 95%
CI: 1.04 - 1.33) or who lived in areas with high-risk IVS-BH (OR: 1.24 / 95% CI: 1.09 -
1.40) were more likely to carry out their dental appointments. Conversely, those who
did not attend the 6 prenatal consultations (OR: 0.49 / 95% CI: 0.46 - 0.53), who did
not receive Bolsa Família (OR: 0.84 / 95% CI: 0.73 - 0.97) or who were aged
between 20-34 years (OR: 0.88 / 95% CI: 0.80 - 0.97) were less likely to attend them.
A Conclusive Technical Report was prepared with the purpose of informing the
municipality's oral health coordination about the main results and conclusions
achieved. When describing the indicator of the proportion of pregnant women who
received dental care in Belo Horizonte in the three four-month periods of 2022, it can
be stated that pregnant women had access to consultations, however, it would have
been necessary to expand it so that all of them could access the service or at least
60% of them, a parameter considered as a target to be achieved for the purposes of
payment for performance. The need for a more efficient registry became evident, so
that the profile of use of the service and the needs of users can be known, including
the sociodemographic conditions analyzed. It is also important to recognize ethnic
minority groups present in the territory so that their particularities and peculiarities
can be recognized. This Master's Thesis is the result of the stricto sensu
Postgraduate Program in Professional Master's in Family Health (PROFSAÚDE)
Inclusive enrichment for dragons : behavioral responses of amputee and non-amputee individuals of bearded dragons pogona vitticeps to different food enrichment items.
No full textStudies on environmental enrichment for captive bearded dragons (Pogona vitticeps) are still very scarce in the literature, but they are of the utmost importance in the search for quality of life for these animals when they are under human care. Environmental enrichment items should be inclusive, allowing disabled animals to explore them and providing good experiences. Therefore, this study aimed to evaluate food enrichment strategies to increase the foraging behavior of captive non-disabled and disabled bearded dragons. This work was carried out with six adult bearded dragons, three of which had one limb amputated and three that had all limbs, kept at the São Paulo Aquarium. Live kingworm larvae (Zophobas morio) were offered as food in three different levels of enrichment challenge (low, medium, high). Behavioral data were collected using focal sampling with instantaneous recording, with a time interval of every 30 s. Results showed that the more complex the food enrichment challenge, the greater the frequency of bearded dragon foraging. In addition, both amputees and non amputees responded similarly to the enrichment items, differing primarily in their activity levels, where amputee individuals showed more tendencies toward ‘stationary’ and ‘lying down’ behaviors. More studies with reptiles should be encouraged so that good management practices become daily protocols for a better quality of life and for rescuing the natural behaviors of animals kept under human care, even those with anatomical disabilities
Effects of guarana (Paullinia cupana) powder on obesity-associated diseases in animal models : a systematic review.
No full textObesity, a public health problem and a risk factor for numerous comorbidities, has stimulated a growing interest in bioactive-rich foods, such as guarana (Paullinia cupana). This systematic review examined the impact of guarana on obesity-related diseases using animal models from January 1990 and November 2023. Seven articles were included in this review, examining guarana’s impact on hyperlipidemia, diabetes, hypercholesterolemia, and obesity. The studies used powdered guarana, provided by orogastric gavage or incorporated into the diet, with doses ranging from 12.5 mg/kg to 2 g/kg. Compelling evidence from our systematic review suggests that guarana powder positively affects biometric parameters, energy metabolism, and biochemical and inflammatory biomarkers, indicating its potential for addressing obesity-related conditions. However, due to the limited number of studies, additional research, including human, clinical trials, is needed to confirm the applicability of these findings to human health and to clarify the mechanisms of action of guarana’s bioactive compounds
Consumo de alimentos segundo classificação nova e prevalência de insônia em egressos de universidades mineiras : coorte CUME.
No full textPrograma de Pós-Graduação em Saúde e Nutrição. Escola de Nutrição, Universidade Federal de Ouro Preto.A insônia é um transtorno do sono com alta prevalência e afeta diretamente a qualidade de vida. Evidências científicas sugerem uma possível associação entre o consumo alimentar e prevenção ou desenvolvimento de insônia. Por esse motivo, o objetivo deste estudo foi analisar o consumo de alimentos segundo a classificação NOVA e a prevalência de insônia auto relatada entre os participantes da Coorte de Universidades Mineiras (CUME). Trata-se de um estudo observacional desenvolvido com dados coletados por questionários online autopreenchidos em dois momentos: a linha de base com perguntas sobre informações antropométricas, hábitos de vida, e condições de saúde, já o questionário de seguimento, aplicado após quatro anos. Os dados do consumo alimentar, linha de base, foram coletados a partir de um questionário de frequência de consumo alimentar e categorizados segundo a extensão e propósito de processamento dos alimentos de acordo com a classificação NOVA: In Natura/Minimamente Processados/Ingredientes culinários (IN/MP/IC), Alimentos Processados (AP), Alimentos ultraprocessados (AUP). A insônia autorreferida foi avaliada por meio da resposta à pergunta “Você sofre de insônia (tem dificuldades para dormir)?” após quatro anos de seguimento. As análises estatísticas constaram de descrição das variáveis sociodemográficas, hábitos de vida, histórico de morbidade e insônia e, posteriormente, avaliou-se a associação entre quartis de consumo alimentar de cada grupo da NOVA com a prevalência de insônia por meio regressão de Poisson ajustada. Os resultados demonstraram que dos 1.956 participantes, 74.2 % eram mulheres, com idade média de 36,56 anos, 42,67% recebiam entre 10 ou mais salários- mínimos e a prevalência de insônia foi de 26,0%. O consumo calórico médio foi de 2.351 kcal, sendo 65,91% provinha dos alimentos IN/MP/IC, 10,14% dos AP e 25,0% dos AUP. Não foram observadas associações entre a classificação NOVA dos alimentos e prevalência de insônia autorreferida: IN/MP/IC [RP=0,87 (IC95%: 0,66; 1,44)]; alimentos processados [RP= 1,08 (IC95%: 0,83 ; 1,39)]; alimentos ultraprocessados [RP = 1, 00 (IC95%: 0,76 ; 1,31) e a combinação de processados e ultraprocessados [RP= 1,10 (IC95%: 0,84 ; 1,45). Logo, não se observou uma associação entre o consumo alimentar segundo o propósito e extensão do processamento e a prevalência de insônia autorreferida entre adultos jovens brasileiros com elevada escolaridade. Estudos longitudinais são necessários para explorar essa associação.Insomnia is a sleep disorder with high prevalence and directly affects quality of life. Scientific evidence suggests a potential association between food consumption and the prevention or development of insomnia. For this reason, the aim of this study was to analyze food consumption according to the NOVA classification and the prevalence of self-reported insomnia among participants of the Cohort of Universities of Minas Gerais (CUME). This is an observational study developed with data collected through self- administered online questionnaires at two points in time: baseline with questions about anthropometric information, lifestyle habits, and health conditions, and the follow-up questionnaire, applied after four years. Food consumption data at baseline were collected through a food frequency questionnaire and categorized according to the extent and purpose of food processing based on the NOVA classification: Unprocessed/Minimally Processed/Culinary Ingredients (IN/MP/CI), Processed Foods (PF), and Ultra-Processed Foods (UPF). Self-reported insomnia was assessed through the response to the question "Do you suffer from insomnia (difficulty sleeping)?" after four years of follow-up. Statistical analyses included the description of sociodemographic variables, lifestyle habits, morbidity history, and insomnia, and subsequently, the association between food consumption quartiles of each NOVA group and the prevalence of insomnia was evaluated using adjusted Poisson regression. The results showed that of the 1,956 participants, 74,2% were women, with a mean age of 36,56 years, 42,67% earned 10 or more minimum wages, and the prevalence of insomnia was 26,0%. The average caloric intake was 2,351 kcal, with 65,91% coming from IN/MP/CI foods, 10,14% from PF, and 25,0% from UPF. No associations were observed between the NOVA classification of foods and the prevalence of self-reported insomnia: IN/MP/CI [PR=0.87 (95% CI: 0.66; 1.44)]; processed foods [PR=1.08 (95% CI: 0,83; 1,39)]; ultra-processed foods [PR=1,00 (95% CI: 0,76; 1,31)]; and the combination of processed and ultra-processed foods [PR=1,10 (95% CI: 0,84; 1,45)]. Therefore, no association was observed between food consumption according to the purpose and extent of processing and the prevalence of self-reported insomnia among highly educated young Brazilian adults. Longitudinal studies are needed to explore this association further
Optimization of 2G ethanol production from sugarcane bagasse : upscaling of soda pretreatment with redox mediator followed by fed-batch enzymatic hydrolysis and co-fermentation.
No full textThis study presents the upscaling of soda pretreatment of sugarcane bagasse (SB) using a new redox mediator (2- hydroxynaphthalene-1,4-dione) obtained from renewable resources, which does not affect enzymatic hydrolysis and fermentation. Upscaling was performed from a 0.5 L batch static stainless steel reactor to a 20 L pulp digester with forced liquor circulation, analogous to digestors used in the pulp and paper industry. Enzymatic hydrolysis of the pretreated material was optimized using the fed-batch method and was then carried out on a larger scale. The fed-batch method, combined with addition of 1 % (v v⁻¹) Tween 80, enabled the solids load to be increased from 10 % to 15 % (w v⁻¹), with an enzyme load of only 3.00 FPU g⁻¹. This led to a maximum total reducing sugars concentration of ~142 g L⁻¹ after 72 h of hydrolysis. Co-fermentation of C5 and C6 sugar-rich hydrolysate by a consortium of CERLEV 47 (Saccharomyces cerevisiae) and CERLEV 1015 (Pichia guilliermondii) led to a maximum 2G ethanol production of 61.3 g L⁻¹ (308 L ethanol per ton of SB). Mass and energy balances demonstrated that the combustion of black liquor, a byproduct of the soda pretreatment, could satisfy the energy demands of the pretreatment, enzymatic hydrolysis, and fermentation, with an energy of 21.11 MJ using the surplus SB (80 %) from 1G ethanol production. This finding indicated that the developed process was robust and had the potential to enhance total 2G ethanol production. This study supports the feasibility of an integrated 1G/ 2G biorefinery by improving energy efficiency, economic viability, and environmental sustainability