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Search Results: 1 - 10 of 80173 matches for " Carlos Roberto Alexandre "
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A educa o em tempos de neoliberalismo
Carlos Roberto Alexandre
Trabalho, Educa??o e Saúde , 2005, DOI: 10.1590/s1981-77462005000100014
Probabilistic Distributions for Acacia Mearnsii De Wild Total Height and the Influence of Environmental Factors  [PDF]
Carlos Roberto Sanquetta, Alexandre Behling, Allan Libano Pelissari, Ana Paula Dalla Corte, Sylvio Péllico Netto, Augusto Arlindo Simon
Journal of Applied Mathematics and Physics (JAMP) , 2014, DOI: 10.4236/jamp.2014.23001

This paper discusses the hypothesis of height distribution on a forest stand of Acacia mearnsii De Wild, known as black wattle. It remains constant at varied growing environments and, in addition, they are not influenced by age factor. The Wakeby equation was applied. The research was carried out in a black wattle stand at varied age levels and over two different agroecological regions where plantations are found: Serra do Sudeste and Encosta do Sudeste, Rio Grande do Sul State, Brazil. It was observed that as the age rises there is an increase in the stand total height; while the number of trees decreases for the lower classes, it increases for the upper ones. This resulted in lengthening of the curve tail to the left and mode shift to the right, generating negative asymmetrical curves. Two types of height distribution were found: the sharp increase of probability in a specific class and some similar probabilities in successive classes. The distribution curves between the cultivation areas were statistically different and therefore the height distribution was dependent of environment.

Numerical Simulation of Microstructural Evolution via Phase-Field Model Coupled to the Solutal Interaction Mechanism  [PDF]
Alexandre Furtado Ferreira, Ingrid Meirelles Salvino Tomaskewski, Késsia Gomes Paradela, Dimas Moraes da Silva, Roberto Carlos Sales
Materials Sciences and Applications (MSA) , 2015, DOI: 10.4236/msa.2015.610092
Abstract: A phase-field model coupled to the multiphase/multiscale model is used to simulate the microstructural morphology and predict the CET during solidification. The considered mechanism for the CET is based on interactions of solute between the equiaxed grains and the advancing columnar front. The results for the solute concentration in liquid region, dendrite tip velocity, volume fraction of the liquid and solid are presented and discussed. The phase-field model is used to simulate the dendritic morphology of an alloy directionally solidified, by imposing a constant temperature gradient. The simulation of the equiaxed grains growth requires a further important element, the growth of grains with different crystallographic orientations. The grain orientations are generated randomly for each nucleus introduced in computational domain. Finally, the coupling results between the multiphase/multiscale model and phase-field are presented and discussed. For higher nuclei density present in the melt, a shorter distance between mold wall and the equiaxed zone in the solidification process can be observed. A solute concentration boundary layer exists in the liquid along the columnar grain contour. The concentrations in the solid indicate the presence of a microsegregation pattern. The simulated results show that the solidification features are consistent with those observed based on the metallographic examinations of cast microstructures reported in the literature.
Methodology for automatic process of the fired ceramic tile's internal defect using IR images and artificial neural network
Andrade, Roberto Márcio de;Eduardo, Alexandre Carlos;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2011, DOI: 10.1590/S1678-58782011000100010
Abstract: in the ceramic industry, rarely testing systems were employed to on-line detect the presence of defects in ceramic tiles. this paper is concerned with the problem of automatic inspection of ceramic tiles using infrared images and artificial neural network (ann). the performance of the technique has been evaluated theoretically and experimentally from laboratory and on line tile samples. it has been performed system for ir image processing and, utilizing an artificial neural network (ann), detecting defected or no defected tile. the system has been applied to detect on-line measurement results achieved at the exit of the press. the above automatic inspection procedures have been implemented and tested on a number of tiles using synthetic and real defects. the results obtained confirmed the efficiency of the methodology defect detection in raw tile and its relevance as a promising approach on-line, as well as included in quality control and inspection programs.
Electrical performance and chemical composition studies on original and falsified Ni-MH batteries
Alexandre Urbano,Jair Scarminio,Carlos Roberto Appoloni,Ricardo Floriano
Semina : Ciências Exatas e Tecnológicas , 2010,
Abstract: We show in this paper that falsifications on technological products have hit even rechargeable nickel metal hydride batteries (Ni-MH). The electrical performance and the electrode chemical composition were investigated for authentic and falsified AAA Ni-MH batteries, purchased in the Londrina market, Paraná State. Battery charge capacities were measured at 0,2 C discharge rate and average electrical power was measured at 0.2 and 0.8 C discharge rate. To perform chemical composition analysis, the batteries were vacuum dismantled and their electrodes were characterized by Energy Dispersive X-Ray Fluorescence (EDXRF) and X-Ray Diffraction (XRD) techniques. It was observed that the charge capacities for the authentic and falsified batteries were 920 and 154 mAh, respectively. The average electrical powers were 210 mW for authentic and 41 mW for falsified batteries. The cathode chemical composition was nickel hydroxide, (Ni(OH)2), for both kinds of batteries. However, the anodes of these batteries were not composed by the same materials. The alloy LaNi5 was identified as the electroactive compound in the anode of the authentic battery, while cadmium hydroxide compound, (Cd (OH)2), was identified in the falsified battery anode. The authentic battery therefore presented six times more charge capacity, five times more power at 0.2 C discharge rate and 6 times at 0.8 C than the falsified battery, and are yet less dangerous to environment due cadmium absence.
Pesticide-Handling Practices in Agriculture in El Salvador: An Example from 42 Patient Farmers with Chronic Kidney Disease in the Bajo Lempa Region  [PDF]
Roberto Mejía, Edgar Quinteros, Alejandro López, Alexandre Ribó, Humberto Cedillos, Carlos M. Orantes, Eliette Valladares, Dina L. López
Occupational Diseases and Environmental Medicine (ODEM) , 2014, DOI: 10.4236/odem.2014.23007

Introduction: The occupational toxic risks from agricultural activities in El Salvador affect human and environmental health. The objective of this paper is to describe the management of pesticide by farmers confirmed with a chronic kidney disease of uncertain etiology (CKDu) not associated to diabetes mellitus or hypertension. Methods: The study involved 42 male patients older than 18 years old with confirmed CKDu that have participated in different stages of pesticides management. This is a cross-sectional study; it was conducted from January to June 2011, in three communities of Bajo Lempa region, El Salvador. An interview was especially designed to investigate which pesticides were used and the farmer practices at different stages of pesticide use. Statistical descriptive analysis was carried out for the several studied variables. Results: All interviewed people had a direct relationship with agricultural activities. The majority of patients had poor education, 19% were illiterate and 55% only have primary education. Most farmers with CKDu had been exposed more than 10 years to hazardous pesticides. The most used pesticide was Hedonal/2, 4 D (100%). 95% interviewed patients mixed different pesticides and 63% dumped empty pesticide containers in the fields. Interviewees did not use appropriate personal protective equipment (100%). Conclusions: There is high use of hazardous pesticides by patients and some of these are banned and some are legal in El Salvador, but prohibited by other countries. Interviewed CKDu patients had high exposure to toxic pesticides due to the misuse in almost all stages. There is inadequate legislation and a poor law enforcement to prevent the misuse of pesticides in El Salvador.

Express?o imuno-histoquímica das metaloproteinases 2 e 9 n?o está associada à progress?o do carcinoma de células escamosas de es?fago
Felin, Izabella Paz Danezi;Grivicich, Ivana;Felin, Carlos Roberto;Fedrigo, Carlos Alexandre;Rocha, Adriana Brondani da;
Jornal Brasileiro de Patologia e Medicina Laboratorial , 2009, DOI: 10.1590/S1676-24442009000400009
Abstract: introduction: esophageal squamous cell carcinoma is an aggressive malignant neoplasia with poor prognosis. the expression of matrix metalloproteinases (mmps), mainly 2 and 9, has been used for the prognostic evaluation of cancer in association with tumor invasion, size and tumoral growth analysis. objective: the aim of the present study was to investigate the immunohistochemical expression of mmp-2 and mmp-9 and evaluate if there is an association between their expression and tumor staging, vascular invasion, local invasion (pt) and tumoral differentiation in esophageal squamous cell carcinoma. material and methods: we conducted a retrospective study using 31 paraffin-embedded specimens of esophageal squamous cell carcinoma obtained by esophagectomies performed at santa maria university hospital, rio grande do sul state, brazil between 1998 and 2003. the histological sections were immunohistochemically studied using a non-biotinylated novolink system for mmp-2 and mmp-9 detection. results: mmp-2 immunohistochemical expression was detected only in 5 cases and did not demonstrate correlation with the variables analyzed. furthermore, mmp-9 immunohistochemical expression was not significantly associated with the other variables. conclusion: mmp-2 and mmp-9 immunohistochemical expression does not seem to be influenced by the variables reported in this study. thus further investigations are required to a better understanding of their association with the prognostic factors of esophageal squamous cell carcinoma.
Influência de adi??es de prata na cinética de recristaliza??o da liga CU-5%Al
ADORNO, Antonio Tallarico;BEATRICE, Carlos Roberto Sobreira;CILENSE, Mário;PETRONI, Ivan Alexandre;HARA, Aroldo Hiroiuqui;
Eclética Química , 2000, DOI: 10.1590/S0100-46702000000100005
Abstract: the influence of additions of 2, 4, 6 and 8 wt.% ag on the recrystallization kinetics of the cu-5wt.%al alloy cold-rolled to reductions up to 40, 70 and 90% was studied using the intercept method for measurements of mean grain size changes with time and temperature. the results indicated a decrease in the grain growth rate and in the activation energy with the increase of silver concentration.
Associa??o de aciclovir oral e imiquimode no tratamento de herpes simples genital hipertrófico em paciente com sida: relato de dois casos
Barbosa, Lívia do Nascimento;Souto, Roberto;Furtado, Ana Luisa;Gripp, Alexandre Carlos;Daxbacher, Egon;
Anais Brasileiros de Dermatologia , 2011, DOI: 10.1590/S0365-05962011000500035
Abstract: chronic herpes simplex can present as exuberant clinical lesions, especially in hiv patients. the most probable mechanism of formation of these lesions is the invasion of the epidermal cd4 t cells by the herpes simplex virus. due to the therapeutic difficulties and the high rates of treatment failure amongst these patients, new drugs are currently being discussed on the literature. studies based on the immunophatology of these lesions have suggested that imiquimod might work as an adjuvant therapy to the antiviral drugs. here we present two cases of excellent response to treatment with topical imiquimod as an adjuvant drug to acyclovir.
Imunossupressores na Dermatologia
Bressan, Aline Lopes;Silva, Roberto Souto da;Fontenelle, Elisa;Gripp, Alexandre Carlos;
Anais Brasileiros de Dermatologia , 2010, DOI: 10.1590/S0365-05962010000100002
Abstract: immunosupressants are drugs that act in cell division and have anti-inflammatory effects. therefore, they are essentially prescribed in the prevention of transplant rejection and in the treatment of autoimmune disorders and chronic inflammatory diseases, whose main example in dermatology is psoriasis. in this work the most important immunosuppressive drugs and orientation to properly administer them are going to be described.
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