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Development of a Methodology for Determination and Analysis of Thermal Displacements of Machine Tools Using Finite Elements Method and Artificial Neural Network

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Journal of Mechanics Engineering and Automation 2014年第6期4卷 488-498页

作者： Romualdo Figueiredo de Sousa Fracisco Augusto Vieira da Silva joao Bosco Aquino Silva jose Carlos de lima Junior Department of Mechanical Engineering Federal University of Paraiba Joao Pessoa 58051-900 Brazil

In the processes of manufacturing, MT （machine tools） plays an important role in the manufacture of work pieces with complex and high dimensional and geometric accuracy. Much of the errors of a machine tool are those which are thermally induced which are from internal and external heat sources acting on the machine. In this paper, a methodology for determining and analyzing the thermal deformation of machine tools using FEM （finite element method） and ANN （artificial neural networks） is presented. After modeling the machine using FEM is defined the location of the heat sources, it is possible to obtain the temperature gradient and the corresponding thermal deformation at predetermined periods. Results obtained with simulations using the software NX.7.5 showed that this methodology is an effective tool in determining the thermal deformation of the machine, correlating the temperature reading at strategic points with volumetric deformation at the tool tip. Therefore, the thermal analysis of the errors in the pair tool part can be established. After training and validation process, the network will be able to make the prediction of thermal errors just stating the temperature values of specific points of each heat source, providing a way for compensation of thermally induced errors.

关键词： Thermal displacement machine tool finite element method artificial neural network.

Tako-Tsubo Cardiomyopathy—The Role of Physical and Emotional Stressors:Two Case Report

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International Journal of Clinical Medicine 2012年第2期3卷 145-150页

作者： Patrícia Margarida Serra Carvalho Jandira Helena lima joao Bernardo Cunha Patricia Gloria Dinis Dias jose Goncalo Diniz Vieira jose Manuel Nascimento Costa Internal Medicine Ward Coimbra University HospitalCoimbraPortugal

Introduction: Tako-Tsubo cardiomyopathy describes a form of acute and reversible left ventricular dysfunction with a clinical presentation, ECG and cardiac biomarkers that makes it indistinguishable from acute coronary syndrome. Case Presentation: The authors present two cases of tako-tsubo cardiomyopathy in postmenopausal women, the first case following an emotional stressful event and a second case following a blood transfusion and probably associated with intravenous catecholamine perfusion. Both had unobstructed coronary arteries and regional wall-motion abnormalities typical of this syndrome. Conclusions: Tako-tsubo cardiomyopathy is a condition often misdiagnosed. A clinical presentation suggestive of acute coronary syndrome in a postmenopausal woman without history of coronary disease and in whom a precipitating stressful event can be found should lead the physician to suspect the diagnosis of tako-tsubo cardiomyopathy. This syndrome associated with blood transfusion has rarely been described.

关键词： Tako-Tsubo Left Ventricle Postmenopausal Stress

Assessment of disease activity in inflammatory bowel diseases:Non-invasive biomarkers and endoscopic scores

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World Journal of Gastrointestinal Endoscopy 2020年第12期12卷 504-520页

作者： Bruno lima Rodrigues Marcia Carolina Mazzaro Cristiane Kibune Nagasako Maria de Lourdes SetsukoAyrizono joao jose Fagundes Raquel Franco Leal Inflammatory Bowel Disease Research Laboratory GastrocenterColorectal Surgery UnitDepartment of SurgerySchool of Medical SciencesUniversity of Campinas(UNICAMP)Campinas 13083-878São PauloBrazil Department of Gastroenterology GastrocenterSchool of Medical SciencesUniversity of Campinas(UNICAMP)Campinas 13083-878Sao PauloBrazil

Inflammatory bowel diseases(IBD)comprise two major forms:Crohn’s disease and ulcerative *** diagnosis of IBD is based on clinical symptoms combined with results found in endoscopic and radiological *** addition,the discovery of biomarkers has significantly improved the diagnosis and management of *** potential genetic,serological,fecal,microbial,histological and immunological biomarkers have been proposed for IBD,and they have been evaluated for clinical routine and clinical ***,especially with biopsy collection,has been considered the standard method to diagnose IBD and to assess clinical activity of the disease,but it is limited to the colon and terminal ileum and is considered *** this reason,non-invasive biomarkers are necessary for this type of chronic inflammatory disease,which affects mostly young individuals,as they are expected to have a long follow-up.

关键词： Inflammatory bowel diseases Biomarkers Endoscopic scores Crohn's disease Ulcerative colitis Inflammation

Analysis of Water Temperature Influenced by Arduino-Controlled on Solar Desalinator of Low Cost

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Journal of Mechanics Engineering and Automation 2019年第4期9卷 133-138页

作者： joao Dehon da Rocha Junior Rafael Leandro Fernandes Melo joao Felipe Vieira lima Isabel Cristina da Costa Souza jose josemar de Oliveira Junior Luiz Guilherme Meira de Souza Departamento de Mecanica Instituto Federal do CearaTabuleiro do NorteCeara62960-000Brazil Departamento de Engenharia Mecanica Universidade Federal do ParanaCuritiba 81530-000Brazil Departamento Bioquimica e Biologia Molecular Universidade Federal do CearaFortaleza 60020-181Brazil Departamento de Engenharia Mecanica Universidade Federal do Rio Grande do NorteNatal 59014-615Brazil

The solar desalinator is a low cost installation and operation equipment that can contribute to tackling the problem of water shortages in the *** of the importance of this equipment,the present work has the objective to quantify the relation of the temperature of the water with the production of the *** this,a compact desalinator with glass cover in square pyramidal form and a heating system controlled by a logic programmer was *** a result,it was verified the efficiency of the logic controller as an auxiliary tool for experimental work and the relationship between temperature ranges and desalination production.

关键词： Solar desalinator temperature of water influence logical programmer solar energy compact desalinator

Application of NURBS for Obtaining Free Form Curves and Surfaces in Spur and Helical Gears by Using CMM （Coordinate Measurement Machine）

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Journal of Mechanics Engineering and Automation 2014年第5期4卷 432-440页

作者： Luiz Henrique Melo Silva Nobrega Verilton Nunes da Silva jose Carlos de lima Junior joao Bosco de Aquino Silva Igor Lucena Peixoto Andrezza Rafael Franklin Alves Silva Department of Mechanical Engineering Federal University of Paraiba Jo6o Pessoa 58051-900 Brazil Department of Mechanical Engineering Federal Institute of Bahia SimOes Filho 43700-000 Brazil Informatics Center Federal University of Paraiba Jo6o Pessoa 58051-900 Brazil Department of Mechanical Engineering Federal Institute of Paraiba Jo6o Pessoa 58900-000 Brazil

Currently, engineering processes require reduced manufacturing time and low cost, in addition to the growing demand for workpieces with high accuracy. Workpieces with complex geometries and free forms has been a common practice in industries from different sectors such as： automotive, aeronautics, bioengineering among others. One way to satisfy the market requirements satisfactorily is making measurements more efficient to make the production process faster, in other words, it is necessary to make the inspection system more accurate and flexible. The coordinate measuring evolved over the past three decades and today it is the technology that best meets the requirements of modem manufacturing through CMMs （coordinate measurement machines）. The CMMs are important tool for design, fabrication and inspection of manufactured products, also used in the application of reverse engineering. These machines are also used by engineers in order to produce an accurate digital model in a virtual space for later use in CAD （computer-aided design）/CAM （computer-aided manufacturing）. It is worth mentioning that the accuracy of the modeling process of given piece depends on the number of control points that are captured on the workpiece surface. Consequently, the laser inspection systems are the best tools for use in reverse engineering, but more expensive when compared to contact measurement systems that use the TTP （touch trigger probe）, also used by CMMs. In this case, this paper aims to present an approach based on NURBS （non-uniform rational B-splines） to obtain free form curves and surfaces from a group of points obtained by using a contact sensor, the touch trigger probe. NURBS is an important mathematical tool and consists of generalizations of Bezier curves and surfaces and B-splines. The approach proposed in this paper can be applied for obtaining free form curves and surfaces in spur and helical gears. Experimental results obtained by measuring spur gears showed that the NU

关键词： Coordinate measurement machine touch trigger probe NURBS reverse engineering.

The Drought of Amazonia in 2023-2024

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American Journal of Climate Change 2024年第3期13卷 567-597页

作者： jose A. Marengo Ana P. Cunha Jhan-Carlo Espinoza Rong Fu Jochen Schöngart Juan C. Jimenez Mabel C. Costa joao M. Ribeiro Sly Wongchuig Siyu Zhao National Center for Monitoring and Early Warning of Natural Disasters/CEMADEN So Jos dos Campos Brazil UNESP/CEMADEN So Jos dos Campos Brazil Graduate School of International Studies Korea University Seoul South Korea Institut des Gosciences de lEnvironnement (IGE) Institut de Recherche pour le Dvelopement (IRD) Saint Martin dHeres France Instituto de Investigacin sobre la Enseanza de las Matemticas (IREM PUCP) Pontificia Universidad Catlica del Per Lima Peru Department of Atmospheric and Oceanic Sciences University of California Los Angeles Los Angeles CA USA Departament of Environmental Dynamics Instituto Nacional de Pesquisas da Amaznia (INPA) Manaus Brazil Global Change Unit (GCU) of the Image Processing Laboratory (IPL) Universitat de Valncia Estudi General (UVEG) Paterna Spain Laboratoire dEtudes en Gophysique et Ocanographie Spatiales (LEGOS) Universit de Toulouse CNES/CNRS/IRD/UT3 Toulouse France

The Amazon basin has experienced an extreme drought that started in the austral summer of 2022-23 and extends into 2024. This drought started earlier than other previous droughts. Although some rain fell during the austral summer, totals remained below average. Higher temperatures during austral winter and spring 2023, which affected most of Central South America, then aggravated drought conditions. This coincided with an intense El Niño and abnormally warm tropical North Atlantic Ocean temperatures since mid-2023. Decreased rainfall across the Amazon basin, negative anomalies in evapotranspiration (derived from latent heat) and soil moisture indicators, as well as increased temperatures during the dry-to-wet transition season, September-October-November (SON) 2023, combined to delay the onset of the wet season in the hydrological year 2023-24 by nearly two months and caused it to be uncharacteristically weak. SON 2023 registered a precipitation deficit of the order of 50 to 100 mm/month, and temperatures +3˚C higher than usual in Amazonia, leading to reduced evapotranspiration and soil moisture indicators. These processes, in turn, determined an exceptionally late onset and a lengthening of the dry season, affecting the 2023-2024 hydrological year. These changes were aggravated by a heat wave from June to December 2023. Drought-heat compound events and their consequences are the most critical natural threats to society. River levels reached record lows, or dried up completely, affecting Amazonian ecosystems. Increased risk of wildfires is another concern exacerbated by these conditions.

关键词： El Niño SST in the Tropical Atlantic Amazon Drought River Levels Heatwave Dry Season Length

Epidemiology and Clinical Features of Mycobacterium avium Complex Pulmonary Disease in a Brazilian Amazon Cohort

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Advances in Microbiology 2024年第6期14卷 287-302页

作者： jose Tadeu Colares Monteiro Adriana Rodrigues Barretto Ruan Seguin Azevedo Quaresma Bianca Miranda Gouveia Ismari Perini Furlaneto Victória Menezes da Costa Yan Corrêa Rodrigues Layana Rufino Ribeiro Ricardo J. de Paula Souza e Guimarães Alex Brito Souza Ana Roberta Fusco da Costa Karla Valéria Batista lima joao de Barros Barreto University Hospital Federal University of Par Belm Brazil Center for Biological and Health Sciences Ph.D. Program in Parasitic Biology in the Amazon Region (PPGBPA) State University of Par (UEPA) Belm Brazil Department of Medicine Centro Universitrio do Par CESUPA Belm Brazil Bacteriology and Mycology Section Evandro Chagas Institute (SABMI/IEC) Ministry of Health Ananindeua Brazil Geoprocessing Laboratory Evandro Chagas Institute/SVSA/MS Ananineua Brazil

The incidence of Mycobacterium avium complex pulmonary disease (MACPD) has been globally increasing. The present study aims to provide a comprehensive analysis of clinical characteristics and treatment response among patients in the Amazon region of Brazil and conduct a retrospective cohort study at a prominent referral hospital in the State of Par, Brazil, from 2012 to 2020. The M. avium group represented 58.9% of cases, followed by M. intracellulare (35.7%), M. colombiense (3.6%), and M. chimaera (1.8%). The majority of patients (73.2%) were female and with an average age of 63 years. Primary clinical manifestations included persistent cough and sputum production. The Charlson comorbidity index (CCI) averaged 2.47, with 36.3% of patients having a CCI score equal to higher than 3. Notably, over 70% of patients had received treatment for pulmonary tuberculosis before initiating treatment for MAC infection. The fibrocavitary radiologic form was the most prevalent (55.4%), frequently exhibiting a bilateral distribution (53.6%). Antimicrobial susceptibility revealed a significant prevalence of MAC resistance to drugs in the therapeutic regimen. Despite this, most of the patients experienced clinical improvement (50%). In conclusion, this study highlights a higher prevalence of MAC infections among middle-aged women, with a history of pulmonary tuberculosis treatment and presenting the fibrocavitary radiological form was predominant.

关键词： MACDP Nontuberculous Mycobacteria Mycobacterium avium Lung Disease