Theoretical and experimental investigation of performance characteristics and design aspects of cross-spring pivots

Cross-spring pivots have been widely employed over the last decades in a broad variety of precision engineering applications due to the high motion repeatability achieved thanks to the absence of stick slip and clearance. In this paper, the non-linear effect of the anticlastic curvature of the leaf-springs is considered for the accurate analytical modeling of the elasto-kinematic behavior of cross-spring pivots. Finite element analyses (FEA), based on a non-linear thin-shell model, are carried out in order to compare them with the analytical results for the main performance parameters of this type of device, i.e. center-shift, rotational stiffness and stress in the leaf-springs. Furthermore, an experimental setup is built to assess the applicability limits of both models. Finally, remarkable performance aspects of cross-spring pivots are discussed aiming for design improvements

Sistema Estrutural e Construtivo do MÓDULO (M) em Madeira como Instrumento de Aproximação Social na Promoção da Cidadania de Crianças e Jovens Socialmente Vulneráveis

O artigo trata sobre a apresentação de sistema estrutural e construtivo em madeira perfilada roliça de reflorestamento, denominado MÓDULO (M), cuja aplicação como artefato arquitetônico visa promover a cidadania e garantir os direitos de crianças e jovens socialmente vulneráveis de comunidades carentes no entorno das cidades de pequeno, médio e grande porte. Historicamente, no Brasil, a madeira tem uso não compatível com a sua relevância na construção civil, notadamente em elementos estruturais. Este trabalho procura um modo não convencional em pensar estruturas, por meio de uma nova abordagem arquitetônica conceitual, que possibilite configurações espaciais das mais diversas, permeadas com preocupações estéticas. Um exemplo desta abordagem é o MÓDULO (M) que reforça a ideia da aplicação da madeira de reflorestamento em estruturas, concebendo espaços arquitetônicos agradáveis e confortáveis e com preocupações ecológicas, causando mínimo impacto ao meio ambiente. O objetivo deste trabalho é apresentar uma estrutura demonstrativa em madeira de reflorestamento que atende a programas funcionais de interesse social, privilegiando prioritariamente às necessidades programáticas de comunidades sobrevivendo em favelas (normalmente situadas nas periferias das cidades) , de crianças e jovens socialmente vulneráveis. Este sistema é projetado para ser implantado em solos de diferentes declividades e de difícil acesso.This article presenting a timber structural and constructive system of round profiled from reforestation log wood, named MODULE (M), whose application as architectural artifact aims to promote citizenship and guarantee the rights of socially vulnerable children and youth from poor communities in the small, medium and large surrounding towns. Historically, in Brazil, the timber use is not compatible with its relevance in construction, especially in structural elements. This paper seeks a way to think in unconventional structures through a new conceptual architectural approach that enables spatial configurations of the most diverse, permeated with aesthetic concerns. An example of this approach is the MODULE (M) which reinforces the idea of applying reforested log wood in structures, designing architectural spaces pleasant and comfortable, with ecological issues, causing minimal impact to its environment. The objective of this paper is to present a timber demonstrative structure that meets social interest case studies, prioritizing programmatic needs of a community socially vulnerable of children and young people, usually located on the outskirts of cities, surviving in housing type slums. This system is designed to be implanted in soils with different declivities and hard access

Numerical simulation of a rapid fatigue test of high Mn-TWIP steel via a high cycle fatigue constitutive law

The generation of reliable data in the high cycle fatigue domain is crucial to support further metallurgic developments of fatigue optimized steel grades. Commonly employed for this aim, traditional standardized characterization methods are expensive and time-consuming. Thus, to circumvent these limitations, different accelerated fatigue testing methodologies have been proposed. In this work, the rapid fatigue test based on stiffness evolution is numerically reproduced using the finite element method for a specific grade of twinning-induced plasticity steel. A high cycle fatigue constitutive law grounded on the continuum damage mechanics framework is employed for this purpose. To adequately capture the material non-linear behavior observed in the experiments, a novel hardening–softening stress–strain curve for damage is proposed. The entire load history in the fatigue domain is modeled. A cycle-jump algorithm is used to improve the computational efficiency of the simulations. It is shown that a reduction of about 55% in the analysis elapsed time is reached by using this algorithm, while the result accuracy is maintained. Finally, the good agreement between numerical and experimental results, revealed by a maximum relative error smaller than 6.0%, evidences the potential of the present constitutive formulation to model the behavior of metals in the high cycle fatigue domain.This work has been done within the framework of the Fatigue4Light (H2020-LC-GV-06-2020) project: “Fatigue modeling and fast testing methodologies to optimize part design and to boost lightweight materials deployment in chassis parts”. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 101006844. The work has been also supported by the Spanish Government program, Spain FPU17/04196. The authors gratefully acknowledge all the received support. Finally, they acknowledge the support received by the Severo Ochoa Centre of Excellence (2019-2023, Spain under the grant CEX2018-000797-S funded by MCIN/AEI/10.13039/501100011033, Spain .Peer ReviewedPostprint (published version

O COMÉRCIO DE VALOR ADICIONADO E A PARTICIPAÇÃO DO BRASIL NAS CADEIAS GLOBAIS DE VALOR/The value-added trade and the participation of Brazil in global value chains: El comercio de valor añadido y la participación de Brazil en cadenas globales de valor

The aim of this paper is to analyze the evolution of Brazilian Domestic Value Added - DVA trade, as well as Brazil's participation in Global Value Chains - CGVs, considering the Brazilian main trading partners, through the Trade in value-added indicators - TiVA and the Inter-Country Input-Output Tables - ICIO, release 2018, made available by the Organization for Economic Co-operation and Development – OECD. The results show that products exported by Brazil to the European Union, China and South Korea have a higher proportion of DVA in relation to total exports. However, they are low value-added products in absolute terms, as they are mostly exported in natura or semi-processed. On the other hand, Products exported by Brazil to Argentina, Mexico, and the Andean region, have a lower proportion of DVA in relation to the total value of exports, however, they are high and medium technology products that use more elaborate processes in their production and make room for insertion of imported content, which corroborates for the greater insertion of Brazil in the GVCs. In addition, they have higher value added in absolute terms.El presente articulo tiene como objetivo analisar la evolución del comercio de Valor Añadido Doméstico - VAD braliseño, así como participación de Brasil en las Cadenas Globales de Valor - CGVs, considerando sus principales socios comerciales, por meio de los indicadores Trade in value-added - TiVA e de las matrices mundiales de aporte-producto Inter-Country, Input-Output Tables - ICIO release 2018, hechas disponibles por la Organisation for Economic Co-operation e Development - OECD. Los resultados mostran que los productos exportados por Brasil para la Unión Europea, China e Corea del Sur presentan maior proporción de VAD, en relación hacia el total de las exportaciones. Sin embargo, son productos con bajo valor añadido en términos absolutos, sí lo son, en su mayoría, exportados in natura o semielaborados. Ya los productos exportados por Brasil a Argentina, México, e la región Andina, presentan menor proporción de VAD en relación hacia el valor total de las exportaciones, sin embargo, son productos de alta e promedia tecnologia e que utilizan procesos más elaborados en su producción e abren más espacio para inserción de contenido importado, o que corrobora para la mayor inserción de Brasil en las CGVs. Además, presentan mayor valor añadido en términos absolutos.O presente artigo tem como objetivo analisar a evolução do comércio de Valor Adicionado Doméstico - VAD brasileiro, assim como participação do Brasil nas Cadeias Globais de Valor - CGVs, considerando os seus principais parceiros comerciais, por meio dos indicadores Trade in value-added – TiVA e das matrizes mundiais de insumo-produto Inter-Country Input-Output Tables – ICIO release 2018, disponibilizadas pela Organisation for Economic Co-operation e Development – OECD. Os resultados mostram que os produtos exportados pelo Brasil para União Europeia, China e Coréia do Sul apresentam maior proporção de VAD, em relação ao total das exportações. No entanto, são produtos com baixo valor adicionado em termos absolutos, pois são, em sua maioria, exportados in natura ou semielaborados. Já os produtos exportados pelo Brasil para Argentina, México, e a região Andina, apresentam menor proporção de VAD em relação ao valor total das exportações, contudo, são produtos de alta e média tecnologia que utilizam processos mais elaborados em sua produção e abrem mais espaço para inserção de conteúdo importado, o que corrobora para a maior inserção do Brasil nas CGVs. Além disso, apresentam maior valor adicionado em termos absolutos. Abstract: The aim of this paper is to analyze the evolution of Brazilian Domestic Value Added - DVA trade, as well as Brazil's participation in Global Value Chains - CGVs, considering the Brazilian main trading partners, through the Trade in value-added indicators - TiVA and the Inter-Country Input-Output Tables - ICIO, release 2018, made available by the Organization for Economic Co-operation and Development – OECD. The results show that products exported by Brazil to the European Union, China and South Korea have a higher proportion of DVA in relation to total exports. However, they are low value-added products in absolute terms, as they are mostly exported in natura or semi-processed. On the other hand, Products exported by Brazil to Argentina, Mexico, and the Andean region, have a lower proportion of DVA in relation to the total value of exports, however, they are high and medium technology products that use more elaborate processes in their production and make room for insertion of imported content, which corroborates for the greater insertion of Brazil in the GVCs. In addition, they have higher value added in absolute terms

O COMÉRCIO DE VALOR ADICIONADO E A PARTICIPAÇÃO DO BRASIL NAS CADEIAS GLOBAIS DE VALOR/The value-added trade and the participation of Brazil in global value chains

O presente artigo tem como objetivo analisar a evolução do comércio de Valor Adicionado Doméstico - VAD brasileiro, assim como participação do Brasil nas Cadeias Globais de Valor - CGVs, considerando os seus principais parceiros comerciais, por meio dos indicadores Trade in value-added – TiVA e das matrizes mundiais de insumo-produto Inter-Country Input-Output Tables – ICIO release 2018, disponibilizadas pela Organisation for Economic Co-operation e Development – OECD. Os resultados mostram que os produtos exportados pelo Brasil para União Europeia, China e Coréia do Sul apresentam maior proporção de VAD, em relação ao total das exportações. No entanto, são produtos com baixo valor adicionado em termos absolutos, pois são, em sua maioria, exportados in natura ou semielaborados. Já os produtos exportados pelo Brasil para Argentina, México, e a região Andina, apresentam menor proporção de VAD em relação ao valor total das exportações, contudo, são produtos de alta e média tecnologia que utilizam processos mais elaborados em sua produção e abrem mais espaço para inserção de conteúdo importado, o que corrobora para a maior inserção do Brasil nas CGVs. Além disso, apresentam maior valor adicionado em termos absolutos. Abstract: The aim of this paper is to analyze the evolution of Brazilian Domestic Value Added - DVA trade, as well as Brazil's participation in Global Value Chains - CGVs, considering the Brazilian main trading partners, through the Trade in value-added indicators - TiVA and the Inter-Country Input-Output Tables - ICIO, release 2018, made available by the Organization for Economic Co-operation and Development – OECD. The results show that products exported by Brazil to the European Union, China and South Korea have a higher proportion of DVA in relation to total exports. However, they are low value-added products in absolute terms, as they are mostly exported in natura or semi-processed. On the other hand, Products exported by Brazil to Argentina, Mexico, and the Andean region, have a lower proportion of DVA in relation to the total value of exports, however, they are high and medium technology products that use more elaborate processes in their production and make room for insertion of imported content, which corroborates for the greater insertion of Brazil in the GVCs. In addition, they have higher value added in absolute terms

Vocal and cervicoscapular evaluation in military wind instrumentalists

OBJETIVO: Este estudo transversal e prospectivo objetivou avaliar qualidade vocal, respiração e região cervicoescapular em instrumentistas de sopro integrantes da Banda Musical do Exército. MÉTODOS: Foram estudados 42 sujeitos do gênero masculino, militares, com idades entre 20 e 45 anos, divididos em: Grupo Experimental, com 30 instrumentistas de sopro, e Grupo Controle, com 12 instrumentistas de percussão. Todos passaram por entrevista; avaliação vocal - registro da voz e análise perceptivo-auditiva com uso da escala GRBASI; avaliação do tipo respiratório; avaliação fisioterapêutica da região cervicoescapular - inspeção visual dos perfis anterior, lateral e posterior, palpação dos músculos trapézio fibras-superiores, esternocleidomastoídeos, escalenos e base de occipital; e testes de mobilidade cervical e de encurtamentos musculares. RESULTADOS: Não houve diferença entre Grupo Experimental e Controle quanto à presença de queixas vocais; os sujeitos do Grupo Experimental apresentaram mais sintomas laríngeos e relataram mais dor em músculo trapézio e região cervical quando comparados aos sujeitos do Controle. Os sujeitos do Grupo Experimental apresentaram maior alteração nos parâmetros vocais tensão e instabilidade do que os sujeitos do Grupo Controle. Constatou-se maior incidência da respiração costodiafragmático-abdominal no Grupo Experimental. Não houve diferença entre os grupos estudados quanto à postura, encurtamentos musculares e mobilidade cervical; porém o Grupo Experimental apresentou mais dor à palpação em músculo trapézio - fibras superiores. CONCLUSÃO: Os militares instrumentistas de sopro apresentaram alterações vocais e da musculatura cervicoescapular e necessitam de ações de promoção à saúde vocal e postural.PURPOSE: This cross-sectional prospective study had the aim to evaluate vocal quality, breathing and the cervicoscapular region in wind instrumentalists of the Army Band. METHODS: Forty-two male military subjects with ages ranging from 20 to 45 years were divided into: Experimental Group, with 30 wind instrumentalists, and Control Group, with 12 percussionists. All subjects underwent an interview, vocal evaluation - voice record and auditory-perceptual analysis using the GRBASI scale, respiratory type evaluation, physical therapy evaluation of the cervicoscapular region - visual examination of anterior, lateral and posterior profiles, palpation of the trapezius, sternocleidomastoid, scalene and base of occipital muscles, and cervical mobility and muscle shortenings tests. RESULTS: No difference was found between Experimental and Control groups regarding the presence of vocal complaints; subjects from the Experimental Group had more laryngeal symptoms and reported more pain in the trapezius muscle and the cervical region, when compared to control subjects. They also had greater alterations in vocal tension and instability parameters than subjects from the Control Group. There was a higher incidence of costodiaphragmatic-abdominal breathing among the Experimental Group subjects. There was no difference between the groups regarding posture, muscle shortenings, and cervical mobility; however, the Experimental Group presented more pain during the palpation of the trapezius muscle. CONCLUSION: The military wind instrumentalists presented vocal and cervicoscapular alterations, and require actions to promote vocal and postural health

Rheumatic Myocarditis: A Poorly Recognized Etiology of Left Ventricular Dysfunction in Valvular Heart Disease Patients

Background: Heart failure occurs in ~10% of patients with acute rheumatic fever (RF), and several studies have shown that cardiac decompensation in RF results primarily from valvular disease and is not due to primary myocarditis. However, the literature on this topic is scarce, and a recent case series has shown that recurrent RF can cause ventricular dysfunction even in the absence of valvular heart disease.Methods: The present study evaluated the clinical, laboratory and imaging characteristics of 25 consecutive patients with a clinical diagnosis of myocarditis confirmed by 18F-FDG PET/CT or gallium-67 cardiac scintigraphy and RF reactivation according to the revised Jones Criteria. Patients underwent three sequential echocardiograms at (1) baseline, (2) during myocarditis and (3) post corticosteroid treatment. Patients were divided according to the presence (Group 1) or absence (Group 2) of reduced left ventricular ejection fraction (LVEF) during myocarditis episodes.Results: The median age was 42 (17–51) years, 64% of patients were older than 40 years, and 64% were women. Between Group 1 (n = 16) and in Group 2 (n = 9), there were no demographic, echocardiographic or laboratory differences except for NYHA III/IV heart failure (Group 1: 100.0% vs. Group 2: 50.0%; p = 0.012) and LVEF (30 [25–37] vs. 56 [49–62]%, respectively; p < 0.001), as expected. Group 1 patients showed a significant reduction in LVEF during carditis with further improvement after treatment. There was no correlation between LVEF and valvular dysfunction during myocarditis. Among all patients, 19 (76%) underwent 18F-FDG PET/CT, with a positive scan in 68.4%, and 21 (84%) underwent gallium-67 cardiac scintigraphy, with positive uptake in 95.2%, there was no difference between these groups.Conclusion: Myocarditis due to rheumatic fever reactivation can cause left ventricular dysfunction despite valvular disease, and it is reversible after corticosteroid treatment

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Leucemia Linfoblástica Aguda (LLA) na população pediátrica: marcadores moleculares e implicações terapêuticas

A Leucemia Linfoblástica Aguda (LLA) é uma forma comum de câncer pediátrico, representando cerca de 80% dos casos de leucemia em crianças. A patologia é caracterizada pela proliferação descontrolada de células-tronco hematopoéticas na medula óssea, e avanços recentes na pesquisa genômica têm proporcionado uma compreensão mais profunda da complexidade molecular subjacente à doença. O presente estudo tem como objetivo oferecer uma visão abrangente dos principais marcadores moleculares e implicações terapêuticas associadas à LLA na população pediátrica. Este estudo, baseado em uma revisão sistemática da literatura científica, abrange o período de 2013 a 2023, utilizando as bases de dados PubMed (Medline), Cochrane Library e Scientific Electronic Library Online (SciELO). Marcadores moleculares preponderantes, como rearranjos cromossômicos específicos (t(12;21), t(1;19), t(9;22)), mutações genéticas distintivas (ETV6-RUNX1, E2A-PBX1, TP53) e amplificação do gene BCR-ABL1, têm sido objeto de estudo aprofundado. Esses marcadores desempenham um papel crucial na estratificação de risco e prognóstico, permitindo uma abordagem mais personalizada no tratamento da LLA em crianças. As implicações terapêuticas derivadas desses marcadores são vastas, destacando a promissora era das terapias direcionadas. Terapias específicas para mutações, como aquelas direcionadas à mutação BCR-ABL1, e inovações em imunoterapia estão moldando o cenário do tratamento da LLA, proporcionando resultados mais eficazes e menos tóxicos. Os resultados destacam a eficácia das terapias direcionadas e a necessidade contínua de pesquisa para otimizar a intervenção terapêutica, melhorar a qualidade de vida dos pacientes pediátricos afetados pela LLA e explorar novas facetas do tratamento. Em conclusão, este artigo fornece uma análise aprofundada dos marcadores moleculares e terapias associadas à LLA na população pediátrica, destacando avanços significativos e delineando áreas para investigação futura