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Engineering（科研） 2019年第9期11卷 576-591页

作者： Bruno Pizol Invernizzi Leandro Gusmã o Silva maurício david martins das neves Nuclear and Energy Research Institute (IPEN) S&#227 o Paulo University S&#227 o Paulo Brazil

Super Duplex Stainless Steel has been studied for oil and gas industry applications since the 90 s, but their welding always is a technical issue. Then different methods were developed to meet all requirements presents in ASME standards, where most of are applied for lower production, when compared to other materials such carbon steel. This study accomplished circumferential welding experiments in base material (BM)—UNS S32750 Super Duplex Stainless Steel with a thickness of 3.68 mm. Welding was performed using GMAW (Gas Metal Arc Welding) process with CMT (Cold Metal Transfer) control and the aid of a Motoman robot and a turntable device, which were used to ensure the accurate positioning of the torch and that the welding has been fully implemented in the 1 G position, respectively. This process achieves higher production in relation other welding process usually applied for this material class. The joints which presented adequate dimensional results were, then, subjected to tensile and hardness Vickers tests. To avoid the lack of penetration problem, the welding was performed using the CMT process combined with pulsed arc, thus, resulting in full penetration and improved surface finish. The results have shown that the CMT procedure, combined with pulsed arc, led to an adequate superficial finishing, mechanical properties and corrosion resistance in accomplishment with the requirements presented in applicable standards.

关键词： GMAW-Welding CMT Automated Welding Stainless Steel Super Duplex Mechanical Properties Vickershardness

Characteristics of Biometallic Alloy to Additive Manufacturing Using Selective Laser Melting Technology

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Journal of Biomaterials and Nanobiotechnology 2018年第1期9卷 89-99页

作者： Marcello Vertamatti Mergulhao mauricio david martins das neves Material Science and Technology Center Nuclear and Energy Research InstituteSao PauloBrazil

Biomaterial powders are in high development due to expansion of additive manufacturing (AM) processes. Selective laser melting (SLM) is a particular AM technology, which completely melts a powder bed layer by laser beam. Investigations of appropriated physical properties of feedstock (powder alloy) were the aim of this study. Cobalt-chromium-molybdenum (Co-Cr-Mo) alloy was used to overview of gas-atomized powder properties in different granulometric ranges (D1 12 - 19 μm, D2 20 - 46 μm and D3 76 - 106 μm), as their: physical, chemical properties and thermal analysis. SLM manufactured standard tensile specimens of usually granulometric range powder size provided mechanical, chemical and thermal properties of biocompatible Co-Cr-Mo alloy. The physical properties showed that powders in the range of 20 to 50 μm provide a better flow ability and packed density, which are relevant characteristics to SLM processing. Manufacturing by SLM process provided suitable mechanical properties in the health area, as well as, maintained the biocompatible properties of the Co-Cr-Mo alloy.

关键词： Biomaterial Co-Cr-Mo Alloy Powder Alloy Additive Manufacturing Selective Laser Melting

Dexamethasone intravitreal implant(Ozurdex) in diabetic macular edema: real-world data versus clinical trials outcomes

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International Journal of Ophthalmology(English edition) 2021年第10期14卷 1571-1580页

作者： Pedro neves Mário Ornelas Inês Matias João Rodrigues Margarida Santos Marco DutraMedeiros david martins Department of Ophthalmology Centro Hospitalar de SetúbalSetúbal 2910-549Portugal Department of Ophthalmology Hospital BeatrizÂngeloLoures 2674-514Portugal Department of Ophthalmology Hospital da Luz SetúbalSetúbal 2900-722Portugal Department of Ophthalmology Centro Hospitalar Lisboa CentralFaculdade de Ciências MédicasNOVA University of LisbonLisbon 1990-237Portugal

AIM: To investigate the safety and efficacy of intravitreal dexamethasone implants(Ozurdex?/DEX) in patients with diabetic macular edema(DME) either na?ve or nonna?ve to anti-VEGF therapies who switched to DEX implant independent of response to anti-vascular endothelial growth factors(anti-VEGFs).METHODS: This was an audit retrospective review of medical records of patients with DME who switched to the DEX intravitreal implant. Patients were divided into 2 groups: patients na?ve to antiangiogenic therapy and patients who were previously treated with anti-VEGFs. Data regarding demographics, changes in mean best-corrected visual acuity(BCVA), central macular thickness(CMT), and intraocular pressure(IOP) was collected over 6 mo. The demographic data mean changes in BCVA, CMT, and IOP were compared. Six-month follow-up data of 47 patients(57 eyes), who either switched to DEX implant irrespective of response to previous treatments or were treatment na?ve before receiving DEX implant, was ***: Improvement in mean BCVA was observed from 1-4 mo after injection with a decreased effect at month 6 as expected, with better outcomes in na?ve compared to non-na?ve patients. A statistically relevant decrease in mean CMT was observed during the follow-up period. An increase in mean IOP was observed in the first 2 mo after DEX therapy. The mean number of injections of the overall population during the 6 mo was 1.3. A subgroup analysis showed no relevant difference between phakic versus pseudophakic patients relative to measured outcomes. There was no cataract progression during the follow-up period and no adverse events ***: This real-life setting study shows that intravitreal DEX implant is effective and safe. The timings of greater therapeutic impact are concordant with previous studies and suggest that earlier treatment with corticosteroids may have an additional benefit in na?ve patients.

关键词： anti-VEGF therapy diabetic macular edema dexamethasone intravitreal implant na?ve eyes steroids

Residual Stress and Fracture Toughness Study in A516 Gr70 Steel Joints Welded and Repaired by Arc Processes

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Engineering（科研） 2023年第11期15卷 749-758页

作者： Régis de Matos Curvelo de Barros mauricio david martins das neves Center for Materials Science and Technology-IPEN Energetyc and Nuclear Research Institute (IPEN) S&atildeo Paulo University S&atildeo Paulo Brazil

Structural components made of steel are used in several areas and require welding for assembly. In some situations, repair of the weld bead, also performed by electric arc welding, can be used to correct, and eliminate any discontinuities. However, electric arc welding causes the presence of residual stresses in the joint, which can impair its performance and not meet specific design requirements. In this paper, welded joints made of ASTM A 516 GR 70 steel plates, with a thickness of 30.5 mm, welded by the MAG—Metal Active Gas process (20% CO2) and using a “K” groove were analysed. The joints were manufactured with seven welding passes on each side of the groove. After welding, one batch underwent repair of the bead by TIG welding (Tungsten Insert Gas) and another batch underwent two repairs by TIG welding. Were presented results of the behaviour of the residual stress profile measured by X-ray diffraction and the Vickers microhardness profile in the joints as well the fracture toughness in the conditions only welded and submitted to repairs. The results indicated that the greater number of repair passes reduced the residual compressive stress values obtained in the material manufacturing process and caused a stabilization on the Vickers hardness values. It was concluded that compressive residual stresses did not play a major role in the R-curve results. The presence of discontinuities in the welded joint caused greater influence on the behaviour of the R curve.

关键词： Weld Repair Weld Fatigue Weld J Integral Residual Stress Microharness

Atlas of precipitation extremes for South America and Africa based on depth-duration-frequency relationships in a stochastic weather generator dataset

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International Soil and Water Conservation Research 2023年第4期11卷 726-742页

作者： Andrew Fullhart david C.Goodrich Menberu B.Meles Paulo Tarso S.Oliveira Cristiano das neves Almeida JoséC.de Araújo Shea Burns Southwest Watershed Research Center USDA-ARS 2000 E.Allen Rd.TucsonAZ85719United States Sustainable Agricultural Water Systems Unit USDA-ARS 239 Hopkins RoadDavisCA95616United States Faculty of Engineering Architecture and Urbanism and GeographyUniversidade Federal de Mato Grosso do SulCampo GrandeMS79070-900Brazil Water Resources and Environmental Engineering Laboratory Universidade Federal da ParaíbaJoao PessoaPB58051-900Brazil Department of Agricultural Engineering Campus do Pici Fortaleza Universidade Federal do CearáFortaleza60020-181Brazil

Information about extreme rainfall is lacking in regions of South America and *** study attempts to fill this scientific gap by use of a gridded parameterization for the stochastic weather generator,CLIGEN,to map depth-duration-frequency(DDF)*** of 500-year point-scale precipitation time series generated at each grid point allowed maps of return period precipitation to be produced for a se-lection of sixteen durations ranging from 10-min to 1-year and for nine return periods from 2 to 500 *** generalized extreme value(GEV)probability distribution was fitted for all durations,and given GEV quantiles,an interpolation method was applied to produce maps at 0.1° resolution that better resolve small-scale spatial climate *** addition to uncertainties related to GEV fitting,this study quantifies prediction intervals based on ground *** validation was important for identifying biases in CLIGEN,although uncertainties were not always satisfactorily defined due to sampling design and other *** daily/multi-day durations,100 stations with daily observations and ≥50-year records were selected for validation against the 0.1° CLIGEN map series,resulting in a median and average absolute error of 13%and 16%,*** sub-daily durations,prediction errors were larger *** analogy using available *** established the degree of bias in CUGEN for sub-daily durations,and three records in Brazil with high temporal resolutions were used to confirm that applied bias adjustments resulted in error ranges similar to the daily/multi-day *** atlas is freely available for study of extreme precipitation.

关键词： Africa Depth-duration-frequency Extreme precipitation South America

Gridded 20-year climate parameterization of Africa and South America for a stochastic weather generator (CLIGEN)

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Big Earth Data 2023年第2期7卷 349-374页

作者： Andrew Fullhart Guillermo E.Ponce-Campos Menberu B.Meles Ryan P.McGehee Gerardo Armendariz Paulo Tarso S.Oliveira Cristiano das neves Almeida José C.de Araújo Werner Nel david C.Goodrich Southwest Watershed Research Center USDA-ARS TucsonAZUSA School of Natural Resources and the Environment University of ArizonaTucsonAZUSA Sustainable Agricultural Water Systems Unit USDA-ARS DavisCAUSA Agricultural and Biological Engineering Purdue UniversityWest LafayetteINUSA Faculty of Engineering Architecture and Urbanism and GeographyFederal University of Mato Grosso do Sul(UFMS)Campo GrandeMSBrazil Water Resources and Environmental Engineering Laboratory Federal University of ParaíbaJoao PessoaPBBrazil Federal University of Fortaleza Department of Agricultural EngineeringFortalezaBrazil Department of Geography and Environmental Science University of Fort HareAliceSouth Africa

CLIGEN is a stochastic weather generator that creates statistically representative timeseries of daily and sub-daily point-scale weather variables from observed monthly statistics and other parameters. CLIGEN precipitation timeseries are used as climate input for various risk-assessment modelling applications as an alternative to observe long-term, high temporal resolution records. Here, we queried gridded global climate datasets (TerraClimate, ERA5, GPM-IMERG, and GLdas) to estimate various 20-year climate statistics and obtain complete CLIGEN input parameter sets with coverage of the African and South American continents at 0.25 arc degree resolution. The estimation of CLIGEN precipitation parameters was informed by a ground-based dataset of >10,000 locations worldwide. The ground observations provided target values to fit regression models that downscale CLIGEN precipitation input parameters. Aside from precipitation parameters, CLIGEN’s parameters for temperature, solar radiation, etc. were in most cases directly calculated according to the original global datasets. Cross-validation for estimated precipitation parameters quantified errors that resulted from applying the estimation approach in a predictive fashion. Based on all training data, the RMSE was 2.23 mm for the estimated monthly average single-event accumulation and 4.70 mm/hr for monthly maximum 30-min intensity. This dataset facilitates exploration of hydrological and soil erosional hypotheses across Africa and South America.

关键词： Climate CLIGEN Africa South America

Carbon Burial in Young Tropical Reservoirs Is Higher at Lower Latitudes*

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Journal of Geoscience and Environment Protection 2021年第12期9卷 84-99页

作者： Elizabeth Sikar Marco Aurelio dos Santos Ana Carolina Moterani Isabella Matvienko Ana Carla martins Veras Juliana Pinto Pereira Dias Orleno Marques da Silva Junior Claudio Pavani Marcelo Amorim Teodosio das neves Milisse Nzualo Ayr Manoel Portilho Bentes Junior Rogerio Duarte Construmaq Sã o Carlos S&#227 o Carlos SP Brazil Programa de Planejamento Energético da Universidade Federal do Rio de Janeiro Brazil Laboratório de Energias Renováveis e Estudos Ambientais da Universidade Federal do Rio de Janeiro Brazil Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá Brazil Programa de Pós-Graduaç ã o em Geografia da Universidade Federal do Amapá Brazil

Man-made environments such as tropical hydroelectric reservoirs alter the preexisting carbon (C) cycle and remove C from circulation through burial in sediments. Carbon burial (CB) was measured using the silica-tracer method during four field surveys in the less than six-year-old Belo Monte tropical reservoir. Fresh C sedimentation was also measured. Belo Monte’s CB median rate 276 (n = 84;min 0;max 352,625 mg C·m-2·d-1) is within the range (230 to 436 mg C·m-2·d-1) of CB rates measured further downstream at the Xingu Ria and higher than the averaged over 50 years oceanic rate 244 mg C·m-2·d

关键词： Carbon Burial Sediments Hydroelectric Reservoirs

Parathyroid ultrasonography and bone metabolic profile of patients on dialysis with hyperparathyroidism

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World Journal of Nephrology 2016年第5期5卷 437-447页

作者： Cláudia Ribeiro Maria Goretti Moreira Guimaraes Penido Milena Maria Moreira Guimaraes Marcelo de Sousa Tavares Bruno das neves Souza Anderson Ferreira Leite Leonardo martins Caldeira de Deus Lucas Joséde Campos Machado Center of Nephrology Santa Casa de Belo Horizonte HospitalBelo Horizonte CEP 30150320Minas GeraisBrazil Pediatric Nephrology Unit School of MedicineFederal University of Minas GeraisBelo Horizonte CEP 30130100Minas GeraisBrazil Pediatric Nephrology Unit Center of NephrologySanta Casa de Belo Horizonte HospitalBelo Horizonte CEP 30150320Minas GeraisBrazil Department of Internal Medicine School of Medic Federal University of Minas GeraisBelo Horizonte C30130100Minas GeraisBrazil School of Medicine Federal University of Minas GeraisBelo Horizonte CEP 30130100Minas GeraisBrazil Department of Cardiology Clinic HospitalFederal University of Minas GeraisBelo Horizonte CEP 30130100Minas GeraisBrazil

AIM To evaluate the parathyroid ultrasonography and define parameters that can predict poor response to treatment in patients with secondary hyperparathyroidism due to renal *** This cohort study evaluated 85 patients with chronic kidney disease stage V with parathyroid hormone levels above 800 pg/mL. All patients underwent ultrasonography of the parathyroids and the following parameters were analyzed: Demographic characteristics(etiology of chronic kidney disease, gender, age, dialysis vintage, vascular access, use of vitamin D), laboratory(calcium, phosphorus, parathyroid hormone, alkaline phosphatase, bone alkaline phosphatase), and the occurrence of bone changes, cardiovascular events and death. The χ~2 test were used to compare proportions or the Fisher exact test for small sample frequencies. Student t-test was used to detect differences between the two groups regarding continuous *** Fifty-three patients(66.4%) had parathyroid nodules with higher levels of parathyroid hormone, calcium and phosphorus. Sixteen patients underwent parathyroidectomy and had higher levels of phosphorus and calcium × phosphorus product(P = 0.03 and P = 0.006, respectively). They also had lower mortality(32% vs 68%, P = 0.01) and lower incidence of cardiovascular or cerebrovascular events(27% vs 73%, P = 0.02). Calcium × phosphorus product above 55 mg^2/dL^2 [RR 1.48(1.06, 2.08), P = 0.03], presence of vascular calcification [1.33(1.01, 1.76), P = 0.015] and previous occurrence of vascular events [RR 2.25(1.27, 3.98), P < 0.001] were risk factors for mortality in this population. There was no association between the occurrence of nodules and *** The identification of nodules at ultrasonography strengthens the indication for parathyroidectomy in patients with secondary hyperparathyroidism due to renal failure.

关键词： Secondary hyperparathyroidism Parathyroid ultrasonography Calcium Phosphorus Parathyroid hormone Alkaline phosphatase Chronic kidney disease Bone alkaline phosphatase

Prevalence of congenital cytomegalovirus infection in preterm,small for gestational age and low birth weight newborns:characteristics and cytokines profile

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World Journal of Pediatrics 2022年第7期18卷 498-504页

作者： Janaina Fortes Lino Llian martins Oliveira Diniz Debora Marques de Miranda Daniela Valadao Freitas Rosa Nathalia Gualberto Souza e Silva Eduardo de Souza Nicolau Larissa Goncalves Rezende Lais Silva Carvalho Marianna Fischer de Paula Lopes Luisa Petri Correa Gabriela Mafra de Oliveira Flavia Miranda da Silva Alves Lorena Batista Pascoal Erika Lima Dolabella Teixeira da Costal Leni Marcia Anchieta Roberta Maia de Castro Romaneli Odete Valadares Maternity Hospital Belo HorizonteBrazil Pediatrics Department.Faculy of Medice of Federal University of Minas Gerais Belo Horizonte.Brazil Molecular Laboratory of the INCT-MM.Faculy of Medicine.Federal University of Minas Gerais-UFMG.Belo Horizonte Brazil Faculty of Medicine.Federal University of Minas Gerais-UFMG Belo Horizonte.Brazil Risoleta Tolentino.neves University Hospital's Maternity Belo HorizonteBrazil Sofia Feldman Maternity Hospital Belo HorizonteBrazil Hospital das Clinicas Maternity-Federal University of Minas Gerais.Belo Horizonte Brazil Pediatrics Department of Federal University of Minas Gerais School Medicine.Minas Gerais.Av Professor Alfredo Balena 190.Belo Horizonte 30130-100Brazil

Cytomegalovirus is the most frequent agent of congenital viral infections,affecting approximately 0.2%-2.4%of live births in different countries[1-7].Universal screening for congenital cytomegalovirus infection in newborns is not a standard practice considering cost-benefit issues and viabil-ity of diagnostic ***,most newborns are asympto-matic and there is no effective treatment for this population[2-5].

关键词： weight birth characteristics

Temporomandibular Disorder in University Students of the Parque das Rosas Campus, Universidade Estácio de SáThat Practice Sports

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Health 2016年第1期8卷 18-23页

作者： Rosineli Paz Cabral Manuel Eduardo Moiolli-Rodrigues Flávia Lima Kleinsorgen Motta Francisco Carlos Kleinsorgen de Souza Motta Juliana Rocha da Silva Larissa Malheiros Neide martins Leonardo Trepte André Luiz G. Abrão Adalgisa Maiworm Luiz Carlos Oliveira Raphael Lemgruber Cardoso Adriano Arnóbio Giuseppe Antonio Presta Danúbia da Cunha de Sá Caputo Sebastião david Santos Filho Éric Heleno F. F. Frederico Mario Bernardo-Filho Severo de Paoli Universidade Estácio de Sá—Campus R9—GEPS R9 Rio de Janeiro Brasil Universidade Estácio de Sá—Campus Parque das Rosas Rio de Janeiro Brasil Departamento de Biofísica e Biometria Instituto de Biologia Roberto Alcantara Gomes Universidade do Estado de Rio de Janeiro Rio de Janeiro Brasil Programa de Pós-Graduacao em Fisiopatologia Clínica e Experimental Faculdade de Ciências Médicas Universidade do Estado do Rio de Janeiro Rio de Janeiro Brasil UniFacex—Centro Universitário do Facex Natal Brasil Programa de Pós-Graduacao em Biociências Instituto de Biologia Roberto Alcantara Gomes Universidade do Estado do Rio de Janeiro Rio de Janeiro Brasil

The stomatognathic system (SS) is a functional unit of the body that depends on the balance of several tissues. It consists of various structures, including the temporomandibular joint. Temporomandibular disorder (TMD) can occur due to alterations in the SS. The Fonseca Anamnestic Index (FAI) is a scale used to evaluate and to characterize the TMD Type: no DTM, mild, moderate and severe. The aim is to evaluate the prevalence of signs and symptoms related to TMD in university students of the Parque das Rosas Campus, Universidade Estácio de Sá that practice sports. This investigation was approved (CAAE number 325678413.9.0000.5284). Two hundred eighth students (110 male and 98 female, aged 19 - 35 years) accepted to be in this investigation. All the participants answered a General Questionnaire (GQ) and the FAI. The GQ had questions about the age, sex and the presence of TMD. The FAI was used. A statistical difference (p > 0.05) was not found about the presence of TMD. Among the female, an elevated number of the students with signal or symptoms related to the temporomandibular with statistic significance (p < 0.05) was observed. In the population without TMD, the prevalence of this disorder is higher between male than female. Considering the FAI, among the female students, there is a prevalence of the Mild Type. Considering the evaluation of the type of TMD among the male and female students no difference was found between male and female to the types mild and moderate, however, the prevalence of the severe Type is higher in female than in male with statistical significance. In conclusion, TMD is a relevant clinical condition with an important prevalence among the university students. Moreover, the type of the TMD could be considered due to prevalence of the Type Severe among the women.

关键词： Temporomandibular Disorder University Student Fonseca Anamnestic Index Prevalence