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Abstract Background Cardiovascular complications of COVID-19 are important aspects of the disease’s pathogenesis and prognosis. Evidence on the prognostic role of troponin and myocardial injury in Latin American hospitalized COVID-19 patients is still scarce. Objectives To evaluate myocardial injury as independent predictor of in-hospital mortality and invasive mechanical ventilation support in hospitalized patients, from the Brazilian COVID-19 Registry. Methods This cohort study is a substudy of the Brazilian COVID-19 Registry, conducted in 31 Brazilian hospitals of 17 cities, March-September 2020. Primary outcomes included in-hospital mortality and invasive mechanical ventilation support. Models for the primary outcomes were estimated by Poisson regression with robust variance, with statistical significance of p<0.05. Results Of 2,925 patients (median age of 60 years [48-71], 57.1% men), 27.3% presented myocardial injury. The proportion of patients with comorbidities was higher among patients with cardiac injury (median 2 [1-2] vs. 1 [0-2]). Patients with myocardial injury had higher median levels of brain natriuretic peptide, lactate dehydrogenase, creatine phosphokinase, N-terminal pro-brain natriuretic peptide, and C-reactive protein than patients without myocardial injury. As independent predictors, C-reactive protein and platelet counts were related to the risk of death, and neutrophils and platelet counts were related to the risk of invasive mechanical ventilation support. Patients with high troponin levels presented a higher risk of death (RR 2.03, 95% CI 1.60-2.58) and invasive mechanical ventilation support (RR 1.87, 95% CI 1.57-2.23), when compared to those with normal troponin levels. Conclusion Cardiac injury was an independent predictor of in-hospital mortality and the need for invasive mechanical ventilation support in hospitalized COVID-19 patients. COVID19 COVID 19 COVID-1 diseases disease s prognosis scarce inhospital hospital Registry 3 cities MarchSeptember March September 2020 variance p005 p 0 05 p<0.05 2925 925 2,92 6 4871, 4871 48 71 , [48-71] 571 57 57.1 men, men men) 273 27 27.3 12 [1-2 vs 02. 02 . [0-2]) peptide dehydrogenase phosphokinase Nterminal N terminal probrain pro Creactive C reactive predictors RR 203 03 2.03 95 1.602.58 160258 1.60 2.58 58 1.60-2.58 187 87 1.87 1.572.23, 157223 1.57 2.23 23 1.57-2.23) COVID1 COVID- 202 p00 p<0.0 292 92 2,9 487 4 7 [48-71 5 57. 27. [1- [0-2] 20 2.0 9 602 1.602.5 16025 160 1.6 258 2.5 1.60-2.5 18 8 1.8 572 1.572.23 15722 157 1.5 223 2.2 1.57-2.23 p0 p<0. 29 2, [48-7 [1 [0-2 2. 1.602. 1602 16 1. 25 1.60-2. 1.572.2 1572 15 22 1.57-2.2 p<0 [48- [ [0- 1.602 1.60-2 1.572. 1.57-2. p< [48 [0 1.60- 1.572 1.57-2 [4 1.57-

Resumo Fundamento As complicações cardiovasculares da COVID-19 são aspectos importantes da patogênese e do prognóstico da doença. Evidências do papel prognóstico da troponina e da lesão miocárdica em pacientes hospitalizados com COVID-19 na América Latina são ainda escassos. Objetivos Avaliar a lesão miocárdica como preditor independente de mortalidade hospitalar e suporte ventilatório mecânico em pacientes hospitalizados, do registro brasileiro de COVID-19. Métodos Este estudo coorte é um subestudo do registro brasileiro de COVID-19, conduzido em 31 hospitais brasileiros de 17 cidades, de março a setembro de 2020. Os desfechos primários incluíram mortalidade hospitalar e suporte ventilatório mecânico invasivo. Os modelos para os desfechos primários foram estimados por regressão de Poisson com variância robusta, com significância estatística de p<0,05. Resultados Dos 2925 pacientes [idade mediana de 60 anos (48-71), 57,1%], 27,3% apresentaram lesão miocárdica. A proporção de pacientes com comorbidades foi maior nos pacientes com lesão miocárdica [mediana 2 (1-2) vs. 1 (0-20)]. Os pacientes com lesão miocárdica apresentaram maiores valores medianos de peptídeo natriurético cerebral, lactato desidrogenase, creatina fosfoquinase, N-terminal do pró-peptídeo natriurético tipo B e proteína C reativa em comparação a pacientes sem lesão miocárdica. Como fatores independentes, proteína C reativa e contagem de plaquetas foram relacionados com o risco de morte, e neutrófilos e contagem de plaquetas foram relacionados ao risco de suporte ventilatório mecânico invasivo. Os pacientes com níveis elevados de troponina apresentaram um maior risco de morte (RR 2,03, IC95% 1,60-2,58) e suporte ventilatório mecânico (RR 1,87;IC95% 1,57-2,23), em comparação àqueles com níveis de troponina normais. Conclusão Lesão cardíaca foi um preditor independente de mortalidade hospitalar e necessidade de suporte ventilatório mecânico em pacientes hospitalizados com COVID-19. COVID19 COVID 19 COVID-1 doença escassos COVID19. 19. COVID19, 19, 3 cidades 2020 invasivo robusta p005 p 0 05 p<0,05 292 idade 6 4871, 4871 48 71 , (48-71) 57,1%, 571 57,1% 57 57,1%] 273 27 27,3 12 (1-2 vs 020. 020 20 . (0-20)] cerebral desidrogenase fosfoquinase Nterminal N terminal própeptídeo pró independentes RR 203 03 2,03 IC95 IC 1,602,58 160258 1,60 2,58 58 1,60-2,58 1,87IC95% 187IC95 1,87 87 1,87;IC95 1,572,23, 157223 1,57 2,23 23 1,57-2,23) normais COVID1 COVID- 202 p00 p<0,0 29 487 4 7 (48-71 57,1 5 27, (1- 02 (0-20) 2,0 IC9 602 1,602,5 16025 160 1,6 258 2,5 1,60-2,5 87IC95 1,87IC95 187IC9 187 1,8 8 1,87;IC9 572 1,572,23 15722 157 1,5 223 2,2 1,57-2,23 p0 p<0, (48-7 57, (1 (0-20 2, 1,602, 1602 16 1, 25 1,60-2, 87IC9 1,87IC9 187IC 18 1,87;IC 1,572,2 1572 15 22 1,57-2,2 p<0 (48- ( (0-2 1,602 1,60-2 87IC 1,87IC 1,572, 1,57-2, p< (48 (0- 1,60- 1,572 1,57-2 (4 (0 1,57-

https://doi.org/10.36660/abc.20220151

Carbon and Nitrogen Stocks and Microbiological Activity Under Forest-Pasture System and Traditional Pasture in Pernambuco
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Pessôa, Gabriel Carlos Moura

; Piscoya, Victor Casimiro

; Rolim Neto, Fernando Cartaxo

; Araújo Filho, Renisson Neponuceno de

; Melo, Robson Carlos Pereira de

; Pessôa, Uriel Calisto Moura

; Silva, Lucas José de Souza

; Cunha Filho, Moacyr

; Almeida, Rafael Costa Schaidhauer de

; Piscoya, Thaisa Oliveira Folha

; Moraes, Alex Souza

; Gomes Filho, Raimundo Rodrigues

; Medeiros, Raimundo Mainar de

; Saboya, Luciano Marcelo Fallé

; Pedrotti, Alceu

; Holanda, Francisco Sandro Rodrigues

; Fernandes, Milton Marques

; Santos, Luiz Diego Vidal

Floresta e Ambiente

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2022, Volume 29 Nº 2 elocation e20210068

Resumo: En | Texto: En | PDF: En

Abstract An adequate amount of soil organic matter is considered essential for long-term sustainable agriculture, ensuring good productivity. Therefore, the present study quantified carbon and nitrogen stocks and microbiological activity in soil of three different areas: Forest-pasture System, Pasture System and preserved Caatinga - used as a reference of the experiment - located in a semi-arid region, in Watershed of Pajeú River, state of Pernambuco, Brazil. Eight trenches were opened in each system to collect soil samples at depths of 0 - 10, 20 - 30 and 50 - 60 cm, for chemical and microbiological analysis. In general, attributes of soil showed better results of land use in the following order: preserved Caatinga - Forest-pasture System - Pasture System.

https://doi.org/10.1590/2179-8087-floram-2021-0068

Rastreamento visual, photoscreening e dispensação de óculos com a tecnologia ready to ClipTM
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Faria, Marco Antônio Rey de

; Dantas, Daniel Oliveira

; Alves, Milton Ruiz

; Medeiros, Bruno César Ferreira de

; Cabral, Ana Beatriz Florêncio

; Dantas, Breno Gustavo Rocha

; Demeda, Vanessa Favero

; Matos Neto, Carlos

; Azevedo, Luciana Arrais de

; Souza, Alessandra Cavalcante de

; Camilo, Leonardo Ferreira

; Silva, Rodolfo Lima e

; Fernandes, Lara Gonçalves

; Silva, Francisco Isaías da

; Carmo, Luizy Millene Silva do

Revista Brasileira de Oftalmologia

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Out 2020, Volume 79 Nº 5 Páginas 309 - 314

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo Introdução: Os rastreamentos visuais realizados nas escolas são, às vezes, a única oportunidade de deteção dos erros de refração não corrigidos (ERN) causadores de baixa visual, prejuízo na aquisição do conhecimento, evasão e repetência escolar, habilidades motoras pobres, dificuldade na interação social e baixa autoestima nos escolares. Objetivos: Comparar a detecção de ERN em escolares do ensino fundamental por meio de rastreamento visual (medida da AV com a tabela de Snellen) e por photoscreener; avaliar a acurácia do SpotTM Vision Screener (Welch Allyn) como autorefrator comparando suas medidas de refração com as do autorrefrator Topcon KR 8000 (Japão) e levantar a proporção de óculos com a tecnologia ready to Clip™ que foram dispensados no momento da avaliação dos escolares. Métodos: Duzentos e noventa e sete escolares foram submetidos à rastreamento visual (ponto de corte: AV monocular ≤ 0,7 e/ou diferença duas linhas de Snellen entre os olhos), photoscreening (ponto de corte: hipermetropia ≥3,00D, miopia ≥0,75D e astigmatismo > 1D) e à mensuração do erro de refração sob cicloplegia com o photoscreener e o autorrefrator. Somente os dados de refração do olho direito foram analisados. Os achados foram convertidos em vetores de magnitude para análise. Resultados: Os valores de sensibilidade e especificidade do método de rastreamento visual foram 67,2% e 63,5% e do photoscreening, foram 76,1% e 79,1%. A diferença da refração do SVS com o autorrefrator foi de +0,154 DE com -0,170 DC no eixo de 6 graus para o olho direito de cada paciente. Conclusões: Na população avaliada o método de rastreamento refrativo por photoscreener foi mais efetivo que o do rastreamento visual. A comparação dos resultados da refração sob cicloplegia com o autorrefrator validou o uso do photoscreener como um método de refração acurado para a mensuração de erros refrativos em escolares. A maioria dos escolares receberam os óculos com a tecnologia ready to Clip™ no momento da prescrição.

Abstract Background: The visual screening performed in schools is sometimes the only opportunity to detect uncorrected refraction errors (URE) causing low visual impairments, prejudice in the acquisition of knowledge, dropout and school repetition, poor motor skills, difficulty in social interaction and low self-esteem in schoolchildren. Objectives: To compare the detection of URE in elementary school children by visual screening (measurement of the AV with the Snellen table) and photoscreening; to evaluate the accuracy of the SpotTM Vision Screener (Welch Allyn) as an autorefractor by comparing its refraction measurements with those of the autorefractor Topcon KR 800 (Japan) and to verify the proportion of glasses with ready to ClipTM technology dispensed at the time of the students’ evaluation. Methods: Two hundred ninety-seven students were submitted to visual screening (cutoff point: AV monocular ≤ 0.7 and/or difference two Snellen lines between the eyes), photoscreening (cutoff point: hypermetropia ≥ 3, 00D, myopia ≥ 0, 75D and astigmatism > 1D) and the measurement of the refraction error under cycloplegia with the photoscreener and autorefractor. Only the refraction data of the right eye were analyzed. The findings were converted into vectors of magnitude for analysis. Results: The sensitivity and specificity values of the visual screening method were 67.2% and 63.5% and photo screening were 76.1% and 79.1%. The mean difference between refraction by SVS and autorefractor was of + 0.154 SD combined with -0.170 DC in the 6-degree axis for the right eye of each patient. Conclusions: In the population evaluated the method of refractive screening by photoscreener was more effective than the visual screening. The comparison of the results of refraction under cycloplegia with the autorefractor validated the use of photoscreener as an accurate refraction method for the measurement of refractive errors in schoolchildren. The majority of the students received their glasses with ready to Clip™ technology at the time of prescription.

https://doi.org/10.5935/0034-7280.20200066 717 downloads

What You Gain and What You Lose in COVID-19: Perception of Medical Students on their Education
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Chinelatto, Lucas Albuquerque

; Costa, Thamara Rodrigues da

; Medeiros, Vitor Macedo Brito

; Boog, Gustavo Henrique Pereira

; Hojaij, Flávio Carneiro

; Tempski, Patricia Zen

; Martins, Milton de Arruda

Clinics

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2020, Volume 75 elocation e2133

Resumo: En | Texto: En | PDF: En

https://doi.org/10.6061/clinics/2020/e2133 2944 downloads

Influence of Angiotensin-converting Enzyme Insertion/Deletion Gene Polymorphism in Progression of Chagas Heart Disease
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Alves, Silvia Marinho Martins

; Alvarado-Arnês, Lúcia Elena

; Cavalcanti, Maria da Glória Aureliano de Melo

; Carrazzone, Cristina de Fátima Velloso

; Pacheco, Antônio Guilherme Fonseca

; Sarteschi, Camila

; Moraes, Milton Ozorio

; Oliveira Junior, Wilson Alves de

; Medeiros, Carolina de Araújo

; Pessoa, Fernanda Gallinaro

; Mady, Charles

; Lannes-Vieira, Joseli

; Ramires, Felix José Alvarez

Revista da Sociedade Brasileira de Medicina Tropical

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2020, Volume 53 elocation e20190488

Resumo: En | Texto: En | PDF: En

Abstract INTRODUCTION: Chagas disease (CD) is a neglected disease caused by the parasite Trypanosoma cruzi. One-third of infected patients will develop the cardiac form, which may progress to heart failure (HF). However, the factors that determine disease progression remain unclear. Increased angiotensin II activity is a key player in the pathophysiology of HF. A functional polymorphism of the angiotensin-converting enzyme (ACE) gene is associated with plasma enzyme activity. In CD, ACE inhibitors have beneficial effects supporting the use of this treatment in chagasic cardiomyopathy. METHODS: We evaluated the association of ACE I/D polymorphism with HF, performing a case-control study encompassing 343 patients with positive serology for CD staged as non-cardiomyopathy (stage A; 100), mild (stage B1; 144), and severe (stage C; 99) forms of Chagas heart disease. For ACE I/D genotyping by PCR, groups were compared using unconditional logistic regression analysis and adjusted for nongenetic covariates: age, sex, and trypanocidal treatment. RESULTS: A marginal, but not significant (p=0.06) higher prevalence of ACE I/D polymorphism was observed in patients in stage C compared with patients in stage A. Patients in stage C (CD with HF), were compared with patients in stages A and B1 combined into one group (CD without HF); DD genotype/D carriers were prevalent in the HF patients (OR = 2; CI = 1.013.96; p = 0.04). CONCLUSIONS: Our results of this cohort study, comprising a population from the Northeast region of Brazil, suggest that ACE I/D polymorphism is more prevalent in the cardiac form of Chagas disease with HF.

https://doi.org/10.1590/0037-8682-0488-2019 738 downloads

A Comparative Study of Abbreviated Heat Treatments for SAE 4130 Steel After Laser Welding
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Mansur, Raquel Alvim de Figueiredo

; Ferreira, Caroline Cristine de Andrade

; Atílio, Isabela

; Carvalho, Sheila Medeiros de

; Braga, Vagner

; Siqueira, Rafael Humberto de Mota

; Lima, Milton Sergio Fernandes de

Materials Research

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2020, Volume 23 Nº 4 elocation e20200162

Resumo: En | Texto: En | PDF: En

Abstract It was verified that SAE 4130 steel plates crack when laser beam welded at room temperature (RT). To overcome this problem, this work proposes a high temperature (HT) laser welding in order to reduce the residual stresses and create a bainitic structure instead of a martensitic one. A conventional post-welding heat treatment (PWHT) had been used as a comparison for HT. The centerline crack disappeared after a heat treatment of both in-situ (HT) or after inserting in a furnace (PWHT) at 500 °C for 10 minutes. The finite element analyses indicated a residual stress reduction from 163.70 to 3.72 MPa in the fusion zone (FZ) of the welds from RT to HT. The hardness obtained in FZ depends on the thermal cycle induced microstructure of the welds as 400 HV, 340 HV and 250 HV, for martensite (RT), tempered martensite (PWHT) and bainite (HT) micro-constituents. The proposed in-situ high-temperature laser beam welding method proved its usefulness to solve the center crack issue in SAE 4130 joints.

https://doi.org/10.1590/1980-5373-mr-2020-0162 825 downloads

Vigor of maize seeds determined by a free image analysis system
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Medeiros, André Dantas de

; Pereira, Márcio Dias

; Silva, Íris Renata Freire

; Capobiango, Nayara Pereira

; Flores, Milton Edgar Pereira

Revista Ciência Agronômica

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Dez 2019, Volume 50 Nº 4 Páginas 616 - 624

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

RESUMO Novas e refinadas tecnologias, baseadas em procedimentos computadorizados, criam potencial para automatização de avaliações laboratoriais, alternativa para a redução de custos e aumento da capacidade de tomada de decisão quanto ao destino de lotes de sementes. O presente trabalho teve como objetivo avaliar a eficiência do software de processamento digital de imagens de plântulas, o SAPL®, na caraterização do potencial fisiológico de sementes de milho, em comparação com informações fornecidas por testes de vigor recomendados para essa espécie. Dez lotes de sementes de milho foram submetidos às avaliações de germinação, primeira contagem de germinação, índice de velocidade de germinação, emergência de plântulas, teste de frio e condutividade elétrica. Os resultados desses testes foram comparados com os dados obtidos com a análise de imagem, que avaliou o desenvolvimento de plântulas aos três e cinco dias, contados a partir do início do teste de germinação, mediante a obtenção de valores de comprimento de plântulas, índice de crescimento, uniformidade de desenvolvimento, índice de vigor e índice de vigor corrigido. O SAPL® é uma alternativa consistente e promissora para avaliação do potencial fisiológico de sementes de milho, tendo apresentado alta correlação de suas variáveis com os testes tradicionais utilizados. A avaliação pode ser realizada no terceiro e quinto dia após a instalação do teste de germinação.

ABSTRACT New and refined technologies based on computerized procedures create the potential for automating laboratory evaluations, constituting an alternative to reduce costs and increase the decision-making capacity regarding the destination of seed lots. The objective of this study was to evaluate the efficiency of the Sistema de Análise de Plântulas (SAPL ®) free digital image processing software of seedlings in characterizing the physiological potential of maize seeds in comparison with information provided by vigor tests recommended for this species. Ten lots of maize seeds were submitted to germination, first germination count, germination speed index, seedling emergence, cold test and electrical conductivity. The results of these tests were compared with the data obtained from the image analysis, which evaluated the development of seedlings at three and five days counted from the beginning of the germination test, by obtaining values of seedling length, growth, development uniformity, vigor index and corrected strength index. SAPL ® is a consistent and promising alternative for evaluating the physiological potential of maize seeds, presenting a high correlation of its variables with the traditional tests used. The evaluation can be performed on the third and fifth day after the germination test is installed.

https://doi.org/10.5935/1806-6690.20190073 630 downloads

Correlation of water-chlorohydrocarbon mutual solubilities using a modified non-quadratic mixing rule and the Cubic-Two-State equation of state
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Cortes-Sánchez, Benjamín

; Cruz-García, David

; Medeiros, Milton

Journal of the Mexican Chemical Society

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Jun 2019, Volume 63 Nº 2 Páginas 82 - 93

Resumo: En Es | Texto: En Es | PDF: En | PDF: Es

Abstract. The Cubic Two-State equation of state was employed to correlate the measured mutual solubilities of water and 23 chlorinated hydrocarbons (CHCs). Following the scheme framework laid out by Medeiros and Brindis-Flores, a nonquadratic Kabadi-Danner type mixing rule is used, where the water-water dispersive parameter is corrected due to the presence of a hydrophobic solute. The model’s three parameters were adjusted to correlate experimental binary liquid-liquid equilibrium data to relatively high accuracy. The observed minimum in CHC solubility in water near ambient conditions is reproduced reliably. Overall deviations from experimental data were 7.8% for CHC solubility in the aqueous phase and 13% for water solubility in the organic phase.

Resumen. La ecuación de estado Cubic Two-State fue empleada para correlacionar las solubilidades mutuas experimentales de sistemas binarios de agua y 23 hidrocarburos clorados (CHC’s). Siguiendo el precedente establecido por Medeiros y Brindis-Flores, se utilizó una regla de mezclado no cuadrática tipo Kabadi-Danner, donde el parámetro dispersivo de la interacción agua-agua es corregido debido a la presencia de solutos hidrofóbicos. Los tres parámetros del modelo se ajustaron de forma de correlacionar los datos experimentales con exactitud relativamente alta. El mínimo de solubilidad de CHC en agua observado en condiciones próximas al ambiente se reprodujo consistentemente. La desviación de los datos calculados respecto a los experimentales fue 7.8% para la solubilidad de CHC en la fase acuosa y 13% para la solubilidad de agua en la fase orgánica.

https://doi.org/10.29356/jmcs.v63i2.770 245 downloads

Phase Separation and Development of the Microstructure for Stainless Steel to Copper Alloy Weld Joints Using a Fiber Laser
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Carvalho, Sheila Medeiros de

; Siqueira, Rafael Humberto de Mota

; Lima, Milton Sergio Fernandes de

Journal of Aerospace Technology and Management

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2019, Volume 11 elocation e4319

Resumo: En | Texto: En | PDF: En

ABSTRACT Stainless steel and copper alloys joints are often applied in aerospace, marine and power industries where both high thermal and electrical conductivity (Cu) and corrosion resistance (steel) are required. In the aerospace industry, in particular for the combustion chamber of rocket engines, copper and steel combinations offer perfect materials selection due to their combined high thermal conductivity and good stiffness. In this work, laser welds were produced with intensity between 3.8 × 104 and 5.7 × 104 W/mm2 and a heat input between 72 and 108 J/mm, giving an aspect ratio of 1.8. The microstructure of the weld beads was marked by chemical heterogeneities due to the phase separation between Cu and Fe in the liquid state. The phase separation gave rise to globular precipitates which further transform due to a secondary precipitation at temperatures below 1000 °C. The steel side part of the weld presents around 20% Cu, leading to a liquation of the grain boundaries and cracking at high heat inputs. The hardness values situated between both base materials and the tensile shear behavior, when the weld is sufficiently tough, present strength up to 350 MPa and elongation up to 10%.

https://doi.org/10.5028/jatm.v11.1083 993 downloads

10.

A Comparative Study of the Heat Input During Laser Welding of Aeronautical Aluminum Alloy AA6013-T4
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Coelho, Bruno Nazário

; Lima, Milton Sergio Fernandes de

; Carvalho, Sheila Medeiros de

; Costa, Adilson Rodrigues da

Journal of Aerospace Technology and Management

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2018, Volume 10 elocation e2918

Resumo: En | Texto: En | PDF: En

ABSTRACT The heat input is the amount of energy supplied per unit length of the welded workpiece. In this study, the effect of two different heat inputs in laser beam welding of a high strength aluminum alloy AA6013-T4 was evaluated from macrostructural and microstructural points of view. The experiments were performed using a continuous wave 2 kW Yb-fiber laser with 100 µm spot size on the upper surface of the workpiece. Keeping the heat input at a given level, 13 or 30 J/mm, the laser power was changed from 650 W to 2 kW and the welding speed from 33 to 150 mm/s. In the condition of higher heat input 30 J/mm it was possible to obtain both cutting and welding processes. For 13 J/mm, welding processes were obtained in conduction and keyhole modes. The equiaxed grain fraction changed with changing speed for the same heat input. The laser processing induced a decrease in the hardness of the weld bead of about 25% due to the solubilization of the precipitates. The estimated absorptivities of the laser beam in the liquid aluminum changed largely with experimental conditions, from 4.6% to 10.5%, being the most significant source of error in measuring the real amount of energy absorbed in the process. For the same heat input the macrostructure of the welded surfaces, i.e., humps and dropouts, changed as well. All these facts indicate that the heat input is not a convenient method to parameterize the laser beam welding parameters aiming the same weld features.

https://doi.org/10.5028/jatm.v10.925 2166 downloads

11.

Relationship between the biomechanical properties of the cornea and anterior segment measurements
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Souza, Murilo Barreto

; de Medeiros, Fabricio Witzel

; Villela, Flavio Fernandes

; Alves, Milton Ruiz

Clinics

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2018, Volume 73 elocation e491

Resumo: En | Texto: En | PDF: En

OBJECTIVE: To evaluate the relationship of biomechanical properties, corneal hysteresis and corneal resistance factor with age, sex and various corneal parameters measured with a Pentacam in normal subjects. METHODS: A total of 226 eyes from 113 patients were enrolled in this study. The subjects underwent Ocular Response Analyzer and Pentacam evaluations. A varying-intercept multilevel regression was implemented using Bayesian inference. The predictor variables were age, sex, central corneal thickness, corneal volume at a 7-mm diameter, anterior chamber angle and volume, anterior chamber depth, mean radius of the corneal curvature and corneal astigmatism. RESULTS: Corneal hysteresis ranged from 5.5 to 14.8 mmHg (mean 10.42±1.74 mmHg), and the corneal resistance factor ranged from 5.7 to 15.5 mmHg (mean 10.23±1.88 mmHg). No predictor variable other than gender and central corneal thickness had a significant correlation with either corneal hysteresis or corneal resistance factor. Corneal hysteresis was positively associated with female sex and with central corneal thickness, and corneal resistance factor was positively associated with central corneal thickness. CONCLUSION: Despite the associations found, only a small fraction of the variance in biomechanical measurements could be explained by the descriptors that were evaluated, indicating the influence of other corneal aspects on the biomechanical characteristics.

https://doi.org/10.6061/clinics/2018/e491 277 downloads

12.

Prospective evaluation of vesicourethral anastomosis outcomes in robotic radical prostatectomy during early experience in a university hospital
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Burttet, Lucas Medeiros

; Varaschin, Gabrielle Aguiar

; Berger, Andre Kives

; Cavazzola, Leandro Totti

; Berger, Milton

; Silva Neto, Brasil

International braz j urol

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Dez 2017, Volume 43 Nº 6 Páginas 1176 - 1184

Resumo: En | Texto: En | PDF: En

ABSTRACT Purpose: Robotic assisted radical prostatectomy (RARP) presents challenges for the surgeon, especially during the initial learning curve. We aimed to evaluate early and mid-term functional outcomes and complications related to vesicourethral anastomosis (VUA), in patients who underwent RARP, during the initial experience in an academic hospital. We also assessed possible predictors of postoperative incontinence and compared these results with the literature. Materials and Methods: We prospectively collected data from consecutive patients that underwent RARP. Patients with at least 6 months of follow-up were included in the analysis for the following outcomes: time to complete VUA, continence and complications related to anastomosis. Nerve-sparing status, age, BMI, EBL, pathological tumor staging, and prostate size were evaluated as possible factors predicting early and midterm continence. Results were compared with current literature. Results: Data from 60 patients was assessed. Mean time to complete VUA was 34 minutes, and console time was 247 minutes. Continence in 6 months was 90%. Incidence of urinary leakage was 3.3%, no patients developed bladder neck contracture or postoperative urinary retention. On multivariate analysis, age and pathological staging was associated to 3-month continence status. Conclusion: Our data show that, during early experience with RARP in a public university hospital, it is possible to achieve good results regarding continence and other outcomes related to VUA. We also found that age and pathological staging was associated to early continence status.

https://doi.org/10.1590/s1677-5538.ibju.2016.0466 790 downloads

13.

Robotic assisted laparoscopic excision of a retroperitoneal Ganglioneuroma
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Burttet, Lucas Medeiros

; Abreu, Fernando Jahn da Silva

; Varaschin, Gabrielle Aguiar

; Silva Neto, Brasil

; Berger, Milton

International braz j urol

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Out 2017, Volume 43 Nº 5 Páginas 997 - 997

Resumo: En | Texto: En | PDF: En

ABSTRACT Introduction: Ganglioneuromas are rare benign neoplasms of the sympathetic nervous system. We describe the case of an incidentally found ganglioneuroma in a woman. To our knowledge this is the first described case of robotic excision of a retroperitoneal ganglioneuroma. Case: A 41-year-old female had an incidental retroperitoneal mass found during a routine US. CT scan and MRI showed an 8.3cm homogeneous mass, adjacent to left kidney upper pole, with peripheral contrast enhancement. Metabolic tests were normal. Patient was positioned in a left flank position and five ports were introduced transperitoneally. A 4-arm Da Vinci SI was docked at a 45° angle to the table. Lesion was dissected along with left adrenal gland, beginning at the left renal hilum and proceeding cephalad. Results: Operating time was 325min and blood loss was 50ml. Patient was discharged after 72hours. There were no postoperative complications. Pathology showed ganglionic cells with neural tissue, and normal adrenal. Discussion: Ganglioneuromas rare benign tumors originating from neural crest and typically affect young adults. Most frequent locations are posterior mediastinum, retroperitoneum and adrenal gland. As in this case, ganglioneuromas are usually silent, slow growing tumors discovered incidentally or by mass effect. US and CT imaging may suggest the diagnosis while MRI findings can be specific for ganglioneuroma. Percutaneous biopsy is an option. Although benign, usually requires surgical excision for treatment. Conclusions: Our case shows that a robotic approach is feasible and allows for meticulous and safe dissection of vascular structures, facilitating adequate hemostasis while maintaining oncological principles.

https://doi.org/10.1590/s1677-5538.ibju.2016.0465 577 downloads

14.

A multidisciplinary weight-loss program: the importance of psychological group therapy
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Ferrari, Gustavo Duarte

; Azevedo, Milton

; Medeiros, Leonardo

; Neufeld, Carmem Beatiz

; Ribeiro, Rosane Pilot Pena

; Rangé, Bernard Pimentel

; Bueno Júnior, Carlos Roberto

Motriz: Revista de Educação Física

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Mar 2017, Volume 23 Nº 1 Páginas 47 - 52

Resumo: En | Texto: En | PDF: En

Abstract In addition to dietary factors and sedentary habits, there is a relationship between obesity and psychological variables, even without a clear distinction between cause, effect, and correlation. Despite this relationship, weight-loss programs are limited to a combination of nutrition and physical education, leaving psychological intervention out of the treatment plan. Self-esteem issues, depression, and anxiety are just some of the emotional conditions related to obesity. However, there is no information in the literature about the importance of psychological counseling in a multidisciplinary program for weight-loss in adults. In this context, the main objective of this study was to analyze the effect of cognitive-behavioral therapy in groups (CBTG) combined with nutrition and physical education within a multidisciplinary approach to treat obesity. 46 individuals (7 men and 39 women) were divided into two groups: control (GC) and psychology (GP). Baseline and intervention measures were obtained prior to intervention and before the final meeting, including physical capacity tests and the administering the International Physical Activities Questionnaire (IPAQ). Both groups attended weekly lectures given by a nutritionist and two physical education professionals for 12 weeks. In addition, the GP participated in weekly sessions of CBTG for the same period. After the program, there were significant changes in body mass index, waist circumference, body fat percentage, and strength of the lower limbs in both groups. In addition to these changes, the GP also showed improvements in diastolic blood pressure and IPAQ scores, being the only one that increased its time of weekly physical activity. Thus, it was concluded that the psychological treatment might play an important role in a multidisciplinary weight-loss program.

https://doi.org/10.1590/s1980-6574201700010007 2852 downloads

15.

Hydrate Equilibrium Modelling with the Cubic two-state Equation of State
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Galicia-Andrés, Edgar

; Medeiros, Milton

Journal of the Mexican Chemical Society

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Dez 2016, Volume 60 Nº 4 Páginas 226 - 237

Resumo: En Es | Texto: En Es | PDF: En | PDF: Es

Abstract: A combination of the cubic two-state equation of state and the van der Waals-Platteeuw model was employed for the description of the hydrate formation thermodynamics, with and without inhibitors. The model parameters were determined from the properties of pure compounds and from phase equilibrium data of binary gas-water and water-inhibitor mixtures. With these parameters, predictions were performed for multicomponent gas-water-inhibitor systems. For single-gas hydrates, the average absolute deviations found for equilibrium pressure did not exceed 8%, whereas for multi-gas hydrates, these deviations were 23% maximum. The proposed model produced good predictions in the presence of inhibitors (methanol, ethanol, ethylene glycol and triethylene glycol), with increasing deviations at higher concentrations of inhibitors.

Resumen: Se empleó la combinación de la ecuación de estado "cubic two-state" con el modelo de van der Waals-Platteeuw para la descripción de la termodinámica de la formación de hidratos, en la presencia y ausencia de inhibidores. Los parámetros del modelo se determinaron a partir de las propiedades de los compuestos puros y de datos de equilibrio de fases de mezclas binarias gas-agua y agua-inhibidores. Para la presión de formación de hidratos de gases sencillos, se encontró un error promedio máximo de 8%, mientras que para mezclas multicomponente la desviación máxima fue de 23%. El modelo propuesto produjo buenas predicciones en la presencia de inhibidores (metanol, etanol, etilenglicol y trietilenglicol), con desviaciones crecientes a medida que se aumenta la concentración del inhibidor.

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