Evaluation of the inelastic behavior of steel columns and frames subjected to minor‐axis bending

Este trabalho tem como objetivo avaliar o comportamento inelástico de sistemas estruturais metálicos submetidos à flexão em torno do eixo de menor inércia. Consideram‐se seções transversais compactas do tipo I. Nessas seções, a flexão em torno do eixo mais fraco apresenta benefícios importantes como a capacidade de desenvolver toda resistência plástica sem ocorrência de flambagem lateral por torção. Adota‐se uma formulação de elementos finitos reticulados planos, na qual o processo de plastificação do aço é acompanhado através do método da rótula plástica refinado. Nesse método, os efeitos decorrentes do escoamento do material são capturados através de um parâmetro que reduz a rigidez do membro estrutural em função do desenvolvimento de regiões plásticas. Emprega‐se ainda nesse método o módulo tangente para considerar a degradação da rigidez em função das forças internas. Efeitos de segunda ordem, tensões residuais e imperfeições geométricas também são considerados nas análises. Como critério para definir o estado limite último de resistência da seção transversal adotam‐se superfícies de plastificação que descrevem a interação entre esforço normal e momento fletor. Para solução das equações não lineares de equilíbrio estrutural usa‐se o método de Newton‐Raphson acoplado a estratégias de continuação. Colunas isoladas e pórticos planos são analisados e os resultados obtidos são comparados aos encontrados por outros pesquisadores. Essas comparações permitem concluir que as técnicas usadas neste trabalho são eficazes e necessárias para uma melhor previsão do comportamento das estruturas com membros submetidos à flexão em torno do eixo de menor inércia.This work presents an evaluation of the inelastic behavior of steel structures subjected to minor‐axis bending. Profiles type I and compact cross‐sections are considered. In these sections, the bent about weak axis presents important benefits, such as the ability to develop all of their plastic resistance without the occurrence of lateral torsional buckling. A nonlinear beam‐column element formulation is adopted, in which the steel yielding process is accounted by the refined plastic‐hinge method. In this method the effects of material yielding are captured by a parameter that reduces the structural member stiffness with the development of cross‐section plastic regions. The tangent modulus approach is used to consider the stiffness degradation caused by the increase in internal forces. Second–order effects, residual stresses and geometric imperfections are also considered in analysis. To define the cross‐section strength ultimate limit state, the study adopts strength surfaces that describe the interaction between internal forces — axial force and bending moment. The nonlinear equations at the structural system level are solved using the Newton‐Raphson iterative strategy coupled with path‐following methods. Isolated steel columns and portal frames are analyzed, and the results obtained are compared to those of other investigators. The comparison shows that the numerical methodology presented in this work is effective and can be used for predicting the behavior of steel structures with members under minor‐axis bending.Peer Reviewe

A novel enzymatically-mediated drug delivery carrier for bone tissue engineering applications: combining biodegradable starch-based microparticles and differentiation agents

In many biomedical applications, the performance of biomaterials depends largely on their degradation behavior. For instance, in drug delivery applications, the polymeric carrier should degrade under physiological conditions slowly releasing the encapsulated drug. The aim of this work was, therefore, to develop an enzymaticmediated degradation carrier system for the delivery of differentiation agents to be used in bone tissue engineering applications. For that, a polymeric blend of starch with polycaprolactone (SPCL) was used to produce a microparticle carrier for the controlled release of dexamethasone (DEX). In order to investigate the effect of enzymes on the degradation behavior of the developed system and release profile of the encapsulated osteogenic agent (DEX), the microparticles were incubated in phosphate buffer solution in the presence of a-amylase and/or lipase enzymes (at physiological concentrations), at 37 C for different periods of time. The degradation was followed by gravimetric measurements, scanning electron microscopy (SEM) and Fourier transformed infrared (FTIR) spectroscopy and the release of DEX was monitored by high performance liquid chromatography (HPLC). The developed microparticles were shown to be susceptible to enzymatic degradation, as observed by an increase in weight loss and porosity with degradation time when compared with control samples (incubation in buffer only). For longer degradation times, the diameter of the microparticles decreased significantly and a highly porous matrix was obtained. The in vitro release studies showed a sustained release pattern with 48% of the encapsulated drug being released for a period of 30 days. As the degradation proceeds, it is expected that the remaining encapsulated drug will be completely released as a consequence of an increasingly permeable matrix and faster diffusion of the drug. Cytocompatibility results indicated the possibility of the developed microparticles to be used as biomaterial due to their reduced cytotoxic effects

Probing singularities in quantum cosmology with curvature scalars

We provide further evidence that the canonical quantization of cosmological models eliminates the classical Big Bang singularity, using the {\it DeBroglie-Bohm} interpretation of quantum mechanics. The usual criterion for absence of the Big Bang singularity in Friedmann-Robertson-Walker quantum cosmological models is the non-vanishing of the expectation value of the scale factor. We compute the `local expectation value' of the Ricci and Kretschmann scalars, for some quantum FRW models. We show that they are finite for all time. Since these scalars are elements of general scalar polynomials in the metric and the Riemann tensor, this result indicates that, for the quantum models treated here, the `local expectation value' of these general scalar polynomials should be finite everywhere. Therefore, we have further evidence that the quantization of the models treated here eliminates the classical Big Bang singularity. PACS: 04.40.Nr, 04.60.Ds, 98.80.Qc.Comment: 9 pages, 6 figure

Amplification of SOX4 promotes PI3K/Akt signaling in human breast cancer

Purpose: The PI3K/Akt signaling axis contributes to the dysregulation of many dominant features in breast cancer including cell proliferation, survival, metabolism, motility, and genomic instability. While multiple studies have demonstrated that basal-like or triple-negative breast tumors have uniformly high PI3K/Akt activity, genomic alterations that mediate dysregulation of this pathway in this subset of highly aggressive breast tumors remain to be determined. Methods: In this study, we present an integrated genomic analysis based on the use of a PI3K gene expression signature as a framework to analyze orthogonal genomic data from human breast tumors, including RNA expression, DNA copy number alterations, and protein expression. In combination with data from a genome-wide RNA-mediated interference screen in human breast cancer cell lines, we identified essential genetic drivers of PI3K/Akt signaling. Results: Our in silico analyses identified SOX4 amplification as a novel modulator of PI3K/Akt signaling in breast cancers and in vitro studies confirmed its role in regulating Akt phosphorylation. Conclusions: Taken together, these data establish a role for SOX4-mediated PI3K/Akt signaling in breast cancer and suggest that SOX4 may represent a novel therapeutic target and/or biomarker for current PI3K family therapies

Prediction of body fat in adolescents: validity of the methods relative fat mass, body adiposity index and body fat index

To verify the validity of anthropometric methods body adiposity index (BAI), relative fat mass (RFM) and body fat index (BFI) to estimate body fat percentage (%BF) in adolescents. Methods A cross-sectional study was carried out with 420 Brazilian adolescents aged 15–19 years, stratified by age (< 18 years, n = 356; ≥ 18 years, n = 64) and sex (boys, n = 216; girls, n = 204). The Anthropometric measurements height, body weight, hip circumference and waist circumference were collected to calculate the %BF by BAI, RFM, BFI methods. Subsequently, %BF was measured by dual emission X-ray absorptiometry (DXA), adopted as a reference method. In the statistical analysis of the data, the Pearson correlation test and the paired t test between %BF obtained by the equations and by the DXA were performed. The method validation criterion was that 68% of individuals should be within an acceptable error range of ± 3.5% of BF and Cohen's Kappa index ≥ 0.61. Additionally, the Bland–Altman graphical analysis was performed. Results All methods showed a high correlation with DXA. For the Kappa index, only the RFM reached the criterion in the total sample (0.67) and in the sample < 18 years (0.68). None of the methods reached the criterion of 68% of the sample within the error range of ± 3.5% of BF. Conclusion The BAI, RFM and BFI equations were not valid for predicting BF in the studied sample according to the criteria adopted regardless of sex or age.info:eu-repo/semantics/publishedVersio

First record of epicadus trituberculatus (Taczanowski, 1872) (araneae, thomisidae, stephanopinae) in the Brazilian Northeast

We present the first record of Epicadus trituberculatus (Taczanowski, 1872) from the Northeast Region of Brazil. The new record is based on six specimens observed in two areas of montane semi-deciduous tropical forest located in two municipalities: Guaramiranga and Pacatuba, Ceará state, Brazil. Of the six specimens observed we collected manually only three to preserve as voucher material. In Brazil, E. trituberculatus has a wide distribution range, which extends from the Atlantic Forest, Amazon, and Cerrado biomes and the Pampa ecoregion. With the new record there are currently six known species of Epicadus in northeastern Brazil155937940CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPnão temnão temnão temThis study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil(CAPES), Finance Code 001 (G.A. Villanueva-Bonilla). We were also financially supported by the Instituto Nacional de Ciência e Tecnologia dos Hymenoptera Para-sitoides (HYMPAR/Sudeste – CNPq/FAPESP/CAPES), and FUNCAP– BPI proc. BP3- 00139-00186.01.00/18 (research grants to J.F. Sobczak

OPTIMIZACIÓN DE INDICADORES DE RENTABILIDAD MEDIANTE EL MODELO DE DEPRECIACIÓN ÁURICA EN NICARAGUA

The implementation of fiscal measures tends to diminish the impact of the tax burden on business economic activities. For years has been used depreciation as a tax shield, so a new model called auric depreciation raised. This approach of the model consisted in weighing higher values in the early years of an asset with regard to the Fibonacci sequence, so serve the improvement of profitability indicators: internal rate of return (IRR) and profitability index (IR). This new model with the straight line and accelerated depreciation (by sum of digits), was compared by the setting of a stage for the enterprise with a minimum annuity to carry the premise of profitability; this annuity with the 30% tax burden was reduced but not before applying three depreciation methods. At the end, average IRR and IR corrected for taxes, proved to be greater with the application of the Auric to planned growth rates higher than 16%, as lower rates is not allowed an appreciable return by any method. This model has, therefore the purpose serve as an incentive for the creation and formalization of new companies, it allows capitalization and survival, and warrants to the tax administration revenue in the long run.La implementación de medidas fiscales tiende a disminuir el impacto de la carga tributaria sobre las actividades económicas empresariales. Por años se ha utilizado la depreciación como escudo fiscal, así que se planteó un nuevo modelo denominado Depreciación Áurica. Este planteamiento del modelo consistió en ponderar valores más altos en los primeros años de un activo con respecto a la sucesión de Fibonacci, para que sirviera a la mejora de los indicadores de rentabilidad: tasa interna de retorno (TIR) e índice de rentabilidad (IR). Se comparó este nuevo modelo con el de línea recta y depreciación acelerada (por suma de dígitos), a través del planteamiento de un escenario para la empresa con una anualidad mínima requerida para cumplir la premisa de rentabilidad; se disminuyó esta anualidad con la carga impositiva del 30% no sin antes aplicar tres métodos de depreciación. Al final, la TIR promedio y el IR corregido por impuestos, resultaron ser mayores con la aplicación del modelo áurico a tasas planificadas superiores al 16%, pues a menores tasas no se permitió una rentabilidad apreciable por ningún método. Este modelo tiene, pues, la finalidad de servir como incentivo para la creación y formalización de nuevas empresas, le permite capitalización y supervivencia, y garantiza a la administración tributaria la recaudación de impuestos a largo plazo

OPTIMIZACIÓN DE INDICADORES DE RENTABILIDAD MEDIANTE EL MODELO DE DEPRECIACIÓN ÁURICA EN NICARAGUA

The implementation of fiscal measures tends to diminish the impact of the tax burden on business economic activities. For years has been used depreciation as a tax shield, so a new model called auric depreciation raised. This approach of the model consisted in weighing higher values in the early years of an asset with regard to the Fibonacci sequence, so serve the improvement of profitability indicators: internal rate of return (IRR) and profitability index (IR). This new model with the straight line and accelerated depreciation (by sum of digits), was compared by the setting of a stage for the enterprise with a minimum annuity to carry the premise of profitability; this annuity with the 30% tax burden was reduced but not before applying three depreciation methods. At the end, average IRR and IR corrected for taxes, proved to be greater with the application of the Auric to planned growth rates higher than 16%, as lower rates is not allowed an appreciable return by any method. This model has, therefore the purpose serve as an incentive for the creation and formalization of new companies, it allows capitalization and survival, and warrants to the tax administration revenue in the long run.La implementación de medidas fiscales tiende a disminuir el impacto de la carga tributaria sobre las actividades económicas empresariales. Por años se ha utilizado la depreciación como escudo fiscal, así que se planteó un nuevo modelo denominado Depreciación Áurica. Este planteamiento del modelo consistió en ponderar valores más altos en los primeros años de un activo con respecto a la sucesión de Fibonacci, para que sirviera a la mejora de los indicadores de rentabilidad: tasa interna de retorno (TIR) e índice de rentabilidad (IR). Se comparó este nuevo modelo con el de línea recta y depreciación acelerada (por suma de dígitos), a través del planteamiento de un escenario para la empresa con una anualidad mínima requerida para cumplir la premisa de rentabilidad; se disminuyó esta anualidad con la carga impositiva del 30% no sin antes aplicar tres métodos de depreciación. Al final, la TIR promedio y el IR corregido por impuestos, resultaron ser mayores con la aplicación del modelo áurico a tasas planificadas superiores al 16%, pues a menores tasas no se permitió una rentabilidad apreciable por ningún método. Este modelo tiene, pues, la finalidad de servir como incentivo para la creación y formalización de nuevas empresas, le permite capitalización y supervivencia, y garantiza a la administración tributaria la recaudación de impuestos a largo plazo

Aquisição Domiciliar De Refrigerantes E De Biscoitos Reduz O Efeito De Uma Intervenção De Promoção De Frutas E Hortaliças

This study examines the influence of increasing household availability of sodas and cookies on the effects of an intervention to promote the consumption of fruits and vegetables. The study analyzed data from 70 families living in low-income communities in the city of Rio de Janeiro, Brazil, selected in a stratified probabilistic sample, and who completed a 30-day food record before and after the intervention. The intervention contributed to a significant increase in the household availability of fruit and vegetables (+2.7 p.p.; 95%CI: 1.5; 4.0), contrary to the trend towards stagnation of such availability in the general population in Brazil. Meanwhile, the purchase of sodas and cookies, which was not the intervention’s target, mirrored the upward trend in the consumption of these products (+5.8 p.p.; 95%CI: 3.3; 8.4). Families that increased their purchase of sodas and cookies showed lower increases, or even decreases, in the purchase of fruits and vegetables (p < 0.05), and had nearly fourfold lower odds of experiencing any increase in the household availability of fruits and vegetables. © 2017, Fundacao Oswaldo Cruz. All rights reserved.333FAPERJ, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de JaneiroMinistério da Saúd

Filtering spin with tunnel-coupled electron wave guides

We show how momentum-resolved tunneling between parallel electron wave guides can be used to observe and exploit lifting of spin degeneracy due to Rashba spin-orbit coupling. A device is proposed that achieves spin filtering without using ferromagnets or the Zeeman effect.Comment: 4 pages, 4 figures, RevTex