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Determination of Residual Stresses Numerically Obtained in ASTM AH36 Steel Welded by TIG Process

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Materials Sciences and Applications 2013年第4期4卷 268-274页

作者： Pablo Batista Guimaraes Paulo Marcelo Almeida Pedrosa Yogendra Prasad Yadava José Maria Andrade Barbosa Aníbal Veras Siqueira Filho ricardo artur sanguinetti ferreira Universidade Federal de Pernambuco Departamento de Engenharia Mecanica Cidade UniversitáriaRecife-PEBrazil

Residual stresses have been numerically determined in welded joints. In this study, the numerical model is based on the coupling of different physical phenomena considering the thermal, mechanical and metallurgical nature of a welding process. The ABAQUS software program was used to perform the numerical simulations, based on the finite element method (FEM). The aspects related to the mathematical modeling of complex welding procedures were pondered with the FEM: variations in the physical and mechanical properties of the materials as a function of the temperature;the transience and the speed of the welding process, the material phase transformations;the different mechanisms of heat exchange with the environment (convection and radiation);all them associated with a high level of nonlinearity. The heat source used in this analytical model for heat supply was the double ellipsoid model proposed by Goldak, in which a 60 mm × 50 mm and 3 mm rectangular ASTM AH36 steel plate was used for the TIG process simulations. Throughout this work, the optimization of the welding procedures currently practiced in petrochemical and ship building industries can be applied to reduce the levels of residual stresses.

关键词： Finite Element Method TIG Welding Temperature Field Residual Stresses

Comprehensive Euler/Lagrange modelling including particle erosion for confined gas-solid flows

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Particuology 2024年第1期84卷 209-235页

作者： Guiherme A.Novelletto ricardo Martin Sommerfeld Multiphase Flow Systems Institute of Process EngineeringOtto-von-Guericke-University MagdeburgHoher Weg 7b06120Halle(Saale)Germany

The present research aims to assess the capability of a comprehensive Euler/Lagrange approach for predicting gas-solid flows and the associated solid particle *** open-source code OpenFOAM®4.1 was used to carry out the numerical simulations,where the standard Lagrangian libraries were substantially extended to account for all necessary *** are tracked considering both translational and rotational motion as well as all relevant forces,such as gravity/buoyancy,drag and transverse lift due to shear and particle *** tracking time step was dynamically adapted ac-cording to the locally relevant time scales,which drastically reduces computational *** approaches are adopted to model particle turbulent dispersion,particle collisions with rough walls and particle-particle *** solid particle erosion models,available in the literature,were considered to estimate pipe bend *** study cases are provided to validate the adopted nu-merical approach and erosion models *** first case intends to evaluate the ability of the extended CFD code to predict the behaviour of gas-solid flows in pneumatic conveying *** goal is achieved by comparing the numerical results with the experimental data obtained by Huber(1997)and Huber and Sommerfeld(1994,1998)in a pneumatic conveying ***,the importance of considering inter-particle collisions and surface roughness for predicting particle velocity,mass flux and mean diameter distributions in gas-solid flows is *** second and third case intend to evaluate the ability of the erosion models in estimating bend erosion in diluted gas-solid *** erosion data obtained experimentally by Mazumder et al.(2008)and Solnordal et al.(2015)in very dilut pneumatic conveying systems is used for validating the numerical results,neglecting now inter-particle collisions and two-way *** a comprehensive analysis of the different influential properti

关键词： Pneumatic conveying Pipe bend Numerical calculation(CFD) Euler/Lagrange approach Erosion models Wall roughness

Unsuccessful tuberculosis treatment outcomes across Brazil's geographical landscape before and during the COVID-19 pandemic:are we truly advancing toward the sustainable development/end TB goal?

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Infectious Diseases of Poverty 2024年第1期13卷 105-106页

作者： Reginaldo Bazon Vaz Tavares Thais Zamboni Berra Yan Mathias Alves Marcela Antunes Paschoal Popolin Antonio Carlos Vieira Ramos Ariela Fehr Tartaro Clara ferreira de Souza ricardo Alexandre Arcencic Department of Maternal-Infant and Public Health Nursing University of São Paulo at Ribeirão Preto College of Nursing (USP/RPCN) Ribeirão Preto São Paulo Brazil Federal University of Tocantins Palmas Campus (FUT) Palmas Brazil State University of Minas Gerais Passos Campus (SUMG) Passos Brazil

Background Tuberculosis is one of the most significant infectious diseases for global public *** reallocation of healthcare resources and the restrictions imposed by the COVID-19 pandemic have hindered access to TB diag-nosis and *** in unfavorable outcomes of the disease have been observed in *** objective of this study was to analyze the spatial distribution of unfavorable TB treatment outcomes in Brazil before and during the *** An ecological study with spatial analysis was conducted with all 5569 municipalities in *** reported cases of tuberculosis between January 2010 and December 2021,as well as reported cases of COVID-19 from Febru-ary 2020 to December 2021,were *** outcomes studied encompass loss to follow-up,drug-resistant tuber-culosis,and *** Getis Ord GI*technique was employed to assess spatial association,and the Kernel density estimator was used to identify areas with concentrated increases or decreases in *** Local Moran's/was used to examine the spatial association between outcomes and cOVID-19 *** study was approved by the Research Ethics Committee of Ribeirao Preto Nursing School,University of Sao *** There were 134,394 cases of loss to follow-up,10,270 cases of drug resistance,and 37,863 *** of high and low values were identified for all three outcomes,indicating significant changes in the spatial distribu-tion *** in concentrations were observed for lost to follow-up cases in the Southeast,while reductions occurred in the Northeast,South,and ***-resistant tuberculosis experienced an increase in the Southern and Southeastern regions and a decrease in the Northeast and ***-related deaths showed notable concentra-tions in the Midwest,Northeast,South,and *** was an increase in high occurrence clusters for deaths after 2020 and 2021 in the *** The pandemic has brought additional chal

关键词： Tuberculosis COVID-19 Spatial analysis Ecological studies

Testicular prostheses-impact on quality of life and sexual function

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Asian Journal of Andrology 2024年第2期26卷 160-164页

作者： Ana Sofia Araujo Sara Anacleto ricardo Rodrigues Catarina Tinoco Andreia Cardoso Carlos Oliveira ricardo Leao Department of Urology Braga's HospitalBraga 4710Portugal Faculty of Medicine Coimbra UniversityCoimbra 3000Portugal

Orchiectomy is the recommended treatment for many testicular ***,testicular prosthesis placement is not always performed for different *** this study,we aimed to evaluate patients'opinions and the impact on sexual function and quality of *** retrospective observational single-center study included patients who underwent orchiectomy between January 2014 and December 2020 at the Department of Urology,Braga's Hospital(Braga,Portugal),where testicular implants were always available and the decision to undergo the procedure was made fully independent of *** completed four questionnaires that assessed demographic data,satisfaction,self-esteem,and sexual *** the 96 patients who underwent orchidectomy,59 replied to the questionnaires,and of these patients,86.4%decided to undergo silicone-based testicular prostheses *** remaining 13.6%refused the implant based on concerns about complications(37.5%),because they felt that it was unnecessary(37.5%),or because it was not offered by the doctor(25.0%).Overall,96.1%of these patients were satisfied with the implant;however,25.5%classified it as"too firm".No statistically significant differences were found in sexual function(all P>0.05).However,it can be observed that there are more patients with prostheses presenting normal sexual activity compared to patients without prostheses(74.0%vs 50.0%),and none of them reported severe erectile dysfunction(0 vs 16.7%).Regarding self-esteem,both patients with and without prostheses present very similar average scores with no statistically significant *** present study highlights the highest level of satisfaction among patients who received testicular *** prostheses implantation is a safe procedure that does not hamper sexual function after orchiectomy.

关键词： orchiectomy patient satisfaction quality of life sexual dysfunction sexual health testicular prostheses

New pharmacological tools:the use of diterpenes to promote adult hippocampal neurogenesis

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Neural Regeneration Research 2024年第8期19卷 1629-1630页

作者： ricardo Gomez-Oliva Pedro Nunez-Abades Carmen Castro Department of Biomedicine Biotechnology and Public HealthDivision of PhysiologyUniversity of CadizCadizSpain Biomedical Research and Innovation Institute of Cadiz(INiBICA) CadizSpain Department of Physiology University of SevilleSevilleSpain

Tissue regeneration maintains homeostasis and preserves the functional features of each ***,not all tissues show a strong repairing *** is the case of the central nervous *** is now well established that the generation of new functional neurons from stem cells in the adult brain occurs in specific regions of the brain of different species such as rodents,birds,primates,and humans(Eriksson et al.,1998).

关键词： capacity maintain preserve

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Targeting epidermal growth factor receptor signaling to facilitate cortical injury repair?

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Neural Regeneration Research 2024年第5期19卷 935-936页

作者： ricardo Gómez-Oliva Pedro Nunez-Abades Carmen Castro Área de Fisiología Facultad de Medicina Universidad de CádizCadizSpain Instituto de Investigación e Innovación en Biomedicina de Cádiz CadizSpain Departamento de Fisiología Facultad de FarmaciaUniversidad de SevillaSevilleSpain

The existence of neural stem cells(NSC)in specific areas of the adult mammalian brain leads to the generation of new neurons involved in homeostatic *** is the case of the NSC of the subventricular zone(SVZ)that produces olfactory bulb(OB)*** neurons integrate into circuits to modulate sensory information and participate in olfactory processing(Bragado Alonso et al.,2019).A series of hierarchical events need to take place to produce OB neurons from NSC of the ***,the activation of quiescent NSC is necessary to produce intermediate transit amplifying progenitors(TAP),which will generate *** latter are cells that maintain a proliferative phenotype while in an immature ***,once they initiate migration toward the OB,they progressively undergo their differentiation into neurons(Kjell et al.,2020).

关键词： ventricular maintain

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Spatial and temporal patterns of forest fires in the Central Monte:relationships with regional climate

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Ecological Processes 2024年第01期13卷 66-79页

作者： Pablo Eugenio Villagra Erica Cesca Leandro Manuel Alvarez Silvia Delgado ricardo Villalba Instituto Argentino de Nivología Glaciología y Ciencias Ambientales–CONICET-CCT Mendoza Facultad de Ciencias Agrarias Universidad Nacional de Cuyo

Background Natural and anthropogenic wildfires burn large areas of arid and semi-arid forests with significant socio-economic and environmental impacts. Fire regimes are controlled by climate, vegetation type, and anthropogenic factors such as ignition sources and human-induced disturbances. Projections of climate and land-use change suggest that these controlling factors will change, altering fire regimes in the near future. In the southern Central Monte, Mendoza, Argentina, the factors that modulate the fire temporal and spatial variability are poorly understood. We reconstructed the fire history of southeast of Mendoza from 1984 to 2023 and investigated the relationships between fire extent and climate variability at seasonal and interannual scales. Burned areas were determined using Google Earth Engine by processing Landsat 5-TM, Landsat 7-ETM+, and Landsat 8-OLI-TIRS sensor *** The region exhibited high spatial and temporal variability in fire occurrence, being a mosaic of areas with different fire histories and recovery times. Between 1985 and 2023, fire recurrence ranged from sites unburned to sites with up to 14 fires. The occurrence of large fires was strongly favored by a combination of a year with abundant spring–early summer precipitation, which favors fuel accumulation, followed by a year of low spring–early summer precipitation. Precipitation and burnt area showed a very pronounced 6–7 year cycle, suggesting a dominant climatic control on fire *** Fire distribution in southeastern Mendoza forests is not homogeneous, resulting in a mosaic of patches with different fire histories. This heterogeneity may be related to vegetation patterns and land use. The temporal variability of fires is strongly influenced by climate variability, which would promote fuel production and subsequent drying. Large fires are concentrated in periods of high interannual precipitation variability. Climate change scenarios predict an increase in tem

关键词： Fire recurrence Fire mapping Recovery time Climate Dry forest Wildfire

Litter production and leaf nutrient concentration and remobilization in response to climate seasonality in the central Amazon

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Journal of Forestry Research 2024年第3期35卷 131-141页

作者： ricardo Antonio Marenco Saul Alfredo Antezana-Vera Daniela Pereira Dias Luiz Antonio Candido Instituto Nacional de Pesquisas da Amazonia Coordenagao de Uso da Terra e Mudanca ClimaticaAv.Andre Araujo 2936ManausAM69067-375Brazil Programa de pos-Graduagao em Agricultura no Tropico Umido Instituto Nacional de Pesquisas da Amazonia-INPAManausAMBrazil Unidade Academica de Ciencias Agrarias Universidade Federal de JataiBR 364km 195JataiGO 75801-615Brazil

Litterfall is the largest source of nutrients to for-est soils of tropical ***,variability in lit-terfall production,nutrient remobilization,and changes in leaf nutrient concentration with climate seasonality remain largely unknown for the central *** study meas-ured litterfall production,leaf nutrient remobilization,and leaf area index on a forest plateau in the central *** was measured at monthly intervals during 2014,while nitrogen,phosphorus,potassium,calcium and mag-nesium concentrations of leaf litter and canopy leaves were measured in the dry and rainy seasons,and remobilization rates *** area index was also recorded in the dry and rainy *** litterfall varied from 33.2(in the rainy season)to 87.6 g m^(-2) in the dry season,while leaf area index increased slightly in the rainy *** seasonality had no effect on concentrations of nitrogen,calcium,and magnesium,whereas phosphorous and potassium responded to rainfall seasonality *** phosphorous increased,potassium decreased during the dry *** seasons,nitrogen,potassium,and phosphorous decreased in leaf litter;calcium increased in leaf litter,while magnesium remained unaffected with leaf ***,the five nutrients had similar remobilization rates over the *** absence of climate seasonality on nutrient remobilization suggests that the current length of the dry season does not alter nutrient remobilization rates but this may change as dry periods become more prolonged in the future due to climate change.

关键词： Throughfall Nutrient cycling Climatic seasonality Leaf mass per area

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Assessing the energy saving potential of using adaptive setpoint temperatures:The case study of a regional adaptive comfort model for Brazil in both the present and the future

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Building Simulation 2024年第3期17卷 459-482页

作者： Daniel Sánchez-García David Bienvenido-Huertas Carlos Rubio-Bellido ricardo Forgiarini Rupp Department of Electrical Engineering University Carlos III of MadridMadridSpain Department of Building Simulation ZEROCEM SLSevilleSpain Department of Building Constructions University of GranadaGranadaSpain Department of Building Constructions II University of SevilleSevilleSpain Section of Design for Sustainability Department of Civil and Mechanical EngineeringTechnical University of DenmarkKgs.LyngbyDenmark

It has been found in recent years that using setpoint temperatures based on adaptive thermal comfort models is a successful method of energy *** studies using adaptive setpoint temperatures incorporate international models from ASHRAE Standard 55 and *** study,however,has instead considered a regional Brazilian adaptive comfort *** study investigates the energy demand arising from the use of a local Brazilian comfort model in order to assess the energy implications from the use of the worldwide ASHRAE Standard 55 adaptive model and various fixed setpoint *** of Brazil’s climate zones,full air-conditioning,mixed-mode building operating modes,present-day climate change scenarios,and future scenarios—specifically Representative Concentration Pathways(RCP)2.6,4.5,and 8.5 for the years 2050 and 2100—have all been taken into account in building energy *** use of adaptive setpoint temperatures based on the Brazilian local model considering mixed-mode has been found to significantly reduce energy consumption when compared to static setpoint temperatures(average energy-saving values ranging from 52%to 58%)and the ASHRAE 55 adaptive model(average values ranging from 15%to 21%).Considering climate change and the mixed-mode Brazilian model,the overall energy demand for the three groups of climatic zones(annual average outdoor temperatures≤21℃,>21 and≤25℃and>25℃)ranged between 2%decrease and 5%increase,4%and 27%increase,and 13%and 45%increase,*** is concluded as a consequence that setting setpoint temperatures based on the Brazilian local adaptive comfort model is a very efficient energy-saving method.

关键词： adaptive thermal comfort building energy simulation energy efficiency climate change adaptive setpoint temperatures local comfort mode