47 results on '"C. R. De Oliveira"'
Search Results
2. Context-Aware Routing in Delay and Disruption Tolerant Networks.
- Author
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Etienne C. R. de Oliveira, Edelberto F. Silva, Diego G. Passos 0001, Juliano Fischer Naves, Débora Christina Muchaluat-Saade, Igor M. Moraes, and Célio Albuquerque 0001
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- 2016
- Full Text
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3. Tilapia-waste flour as a natural nutritional replacer for bread: A consumer perspective.
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Maria Lúcia G Monteiro, Eliane T Mársico, Manoel S Soares Junior, Rosires Deliza, Denize C R de Oliveira, and Carlos A Conte-Junior
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Medicine ,Science - Abstract
Six bread formulations with different levels of tilapia-waste flour (BTF0%, BTF2.5%, BTF5%, BTF10%, BTF15%, and BTF20%) were analyzed for nutritional composition and sensory characterization. Tilapia-waste flour (TF) increased (P < 0.05) the lipid, protein and ash contents, and decreased (P < 0.05) the levels of carbohydrates and total dietary fiber. BTF0%, BTF2.5% and BTF5% received the highest (P < 0.05) scores for acceptance and preference. Despite this apparent consumer preference for low or no levels, TF can be added to bread at levels below 12.17% (P < 0.05) without triggering consumer rejection. TF changed (P < 0.05) the sensory characterization of bread because of a disagreeable flavor, aroma, and texture; however, airy appearance, sticky in the teeth and cream color did not influence the overall liking. TF at 5% enhanced the nutritional value while maintaining acceptable sensory scores for bread, constituting a potential strategy to satisfy consumer and industry requirements.
- Published
- 2018
- Full Text
- View/download PDF
4. Context adaptation in delay and disruption tolerant networks.
- Author
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Edelberto F. Silva, Etienne C. R. de Oliveira, Célio Vinicius N. de Albuquerque, and Débora C. Muchaluat-Saade
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- 2012
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5. NECTAR: a DTN routing protocol based on neighborhood contact history.
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Etienne C. R. de Oliveira and Célio Vinicius N. de Albuquerque
- Published
- 2009
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6. Management Issues on Wireless Mesh Networks.
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Jairo Leite Duarte, Diego G. Passos 0001, Rafael L. Valle, Etienne C. R. de Oliveira, Débora C. Muchaluat-Saade, and Célio Vinicius N. de Albuquerque
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- 2007
- Full Text
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7. Anticariogenic Properties of ent-Pimarane Diterpenes Obtained by Microbial Transformation
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Sergio R. Ambrosio, Luiz E. Gregorio, Wilson R. Cunha, Dioneia C. R. de Oliveira, Nilton S. Arakawa, Suraia Said, Niege A. J. C. Furtado, Rodrigo C. S. Veneziani, Marcela E. Severiano, Thiago S. Porto, Carlos H. G. Martins, and Marilia R. Simao
- Subjects
Ent-pimara-8(14),15-dien-19-oic acid ,microbial transformation ,diterpenes ,anticariogenic properties ,antimicrobial activity ,Organic chemistry ,QD241-441 - Abstract
In the present work, the anticariogenic activities of three pimarane-type diterpenes obtained by fungal biotransformation were investigated. Among these metabolites, ent-8(14),15-pimaradien-19-ol was the most active compound, displaying very promising MIC values (ranging from 1.5 to 4.0 μg mL-1) against the main microorganisms responsible for dental caries: Streptococcus salivarius, S. sobrinus, S. mutans, S. mitis, S. sanguinis, and Lactobacillus casei. Time kill assays performed with ent-8(14),15-pimaradien-19-ol against the primary causative agent S. mutans revealed that this compound only avoids growth of the inoculum in the first 12 h (bacteriostatic effect). However, its bactericidal effect is clearly noted thereafter (between 12 and 24 h). The curve profile obtained by combining ent-8(14),15-pimaradien-19-ol and chlorhexidine revealed a significant reduction in the time necessary for killing S. mutans compared with each of these two chemicals alone. However, no synergistic effect was observed using the same combination in the checkerboard assays against this microorganism. In conclusion, our results point out that ent-8(14),15-pimaradien-19-ol is an important metabolite in the search for new effective anticariogenic agents.
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- 2010
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8. PACKING SUBORDINACY WITH APPLICATION TO SPECTRAL CONTINUITY
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Silas L. Carvalho, C. R. De Oliveira, and Vanderlea R. Bazao
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General Mathematics ,010102 general mathematics ,0103 physical sciences ,Mathematical analysis ,010307 mathematical physics ,0101 mathematics ,01 natural sciences ,Mathematics - Abstract
By using methods of subordinacy theory, we study packing continuity properties of spectral measures of discrete one-dimensional Schrödinger operators acting on the whole line. Then we apply these methods to Sturmian operators with rotation numbers of quasibounded density to show that they have purely $\unicode[STIX]{x1D6FC}$-packing continuous spectrum. A dimensional stability result is also mentioned.
- Published
- 2019
9. Reliability and validity of six-minute step test in patients with heart failure
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Renata Gonçalves Mendes, R.S. Marinho, P.B. dos Santos, Juliano Ferreira Arcuri, Meliza Goi Roscani, C. R. de Oliveira, Audrey Borghi-Silva, Soraia Pilon Jürgensen, Flávia Cristina Rossi Caruso, and Cássia da Luz Goulart
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medicine.medical_specialty ,Medicine (General) ,Physiology ,QH301-705.5 ,Immunology ,Concurrent validity ,Biophysics ,Ocean Engineering ,Heart failure ,Walk Test ,Exercise intolerance ,Biochemistry ,R5-920 ,Oxygen Consumption ,Exercise tolerance ,Internal medicine ,Functional capacity ,Six-minute step test ,Medicine ,Humans ,General Pharmacology, Toxicology and Pharmaceutics ,Biology (General) ,Reliability (statistics) ,Aged ,Heart Failure ,Ejection fraction ,Exercise Tolerance ,business.industry ,General Neuroscience ,Rehabilitation ,VO2 max ,Reproducibility of Results ,Workload ,Stroke Volume ,Cell Biology ,General Medicine ,Stroke volume ,Middle Aged ,medicine.disease ,Cardiopulmonary exercise testing ,Cardiology ,Exercise Test ,medicine.symptom ,business ,Research Article - Abstract
Exercise intolerance is the hallmark consequence of advanced chronic heart failure (HF). The six-minute step test (6MST) has been considered an option for the six-minute walk test because it is safe, inexpensive, and can be applied in small places. However, its reliability and concurrent validity has still not been investigated in participants with HF with reduced ejection fraction (HFrEF). Clinically stable HFrEF participants were included. Reliability and error measurement were calculated by comparing the first with the second 6MST result. Forty-eight hours after participants underwent the 6MST, they were invited to perform a cardiopulmonary exercise test (CPET) on a cycle ergometer. Concurrent validity was assessed by correlation between number of steps and peak oxygen uptake (V̇O2 peak) at CPET. Twenty-seven participants with HFrEF (60±8 years old and left ventricle ejection fraction of 41±6%) undertook a mean of 94±30 steps in the 6MST. Intra-rater reliability was excellent for 6MST (ICC=0.9), with mean error of 4.85 steps and superior and inferior limits of agreement of 30.6 and -20.9 steps, respectively. In addition, strong correlations between number of steps and CPET workload (r=0.76, P
- Published
- 2020
10. Helminths Infecting the Cat-eyed Snake Leptodeira Annulata Linnaeus 1758 (Squamata: Dipsadidae) in a Semiarid Region of Brazil
- Author
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T. Gonçalves De Souza, Robson W. Ávila, A. Ferreira Da Silva-Neta, C. R. De Oliveira, J. Da Cunha Xavier Nunes, C. De Sousa Silva, and E. F. Fernandes De Carvalho
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0301 basic medicine ,Medicine (General) ,Squamata ,Fauna ,Agriculture (General) ,Zoology ,parasites ,Pentastomida ,S1-972 ,Dipsadidae ,03 medical and health sciences ,R5-920 ,Paratenic ,Physaloptera ,Leptodeira ,Helminths ,nematoda ,biology ,neotropical ,030108 mycology & parasitology ,biology.organism_classification ,snakes ,reptiles ,Animal Science and Zoology ,Parasitology ,Acanthocephala ,Research Article - Abstract
Snakes have diverse feeding and living habits, being exposed to a variety of endoparasite communities. However, more studies are still necessary to document these relationships. We examined 18 specimens of the cat-eyed snake Leptodeira annulata from a semi-arid region in Northeast Brazil. Eight taxa of parasites were found, with higher prevalence of cystacanths (Acanthocephala). Five nematode species (Hexametra boddaertii, Oswaldocruzia sp., Oxyascaris sp., Physaloptera sp. and Raillietnema spectans) and the pentastome Raillietiella furcocerca represent a new parasitism record for the host studied. Our results also showed that L. annulata could act as paratenic host for acanthocephalans. These results contribute to the knowledge of the helminth fauna of L. annulata.
- Published
- 2018
11. First Report of Athesmia Foxi Goldberger and Crane, 1911 (Digenea, Dicrocoeliidae) from Chrysocyon Brachyurus (Illiger, 1815) (Carnivora, Canidae) and Pathological Findings
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I. de Oliveira, Hassan Jerdy Leandro, F. C. R. de Oliveira, S. S. Mello Gallo, C. Demarque, L. S. da Silveira, and Nicole Brand Ederli
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0106 biological sciences ,Medicine (General) ,Agriculture (General) ,030231 tropical medicine ,Athesmia foxi ,010607 zoology ,Zoology ,Case Report ,Biology ,01 natural sciences ,Dicrocoeliidae ,Digenea ,S1-972 ,03 medical and health sciences ,0302 clinical medicine ,R5-920 ,Carnivora ,Helminths ,Parasite hosting ,Chrysosyon ,Canidae ,Morphometrics ,Host (biology) ,Biliary hyperplasia ,biology.organism_classification ,histopathology ,Animal Science and Zoology ,Parasitology ,Brazil - Abstract
Summary Chrysocyon brachyurus, the largest South American canid, is a native species of the Brazilian cerrado. The present study is aimed to report the occurrence of the trematode, Athesmia foxi, in the liver of a new host, C. brachyurus, and to describe its morphology and pathology. One C. brachyurus individual was necropsied and examined for the presence of parasites. Worms were collected from the bile ducts and based on morphological and morphometrical characteristics, such as a relatively large, slender, aspinose, elongated shape with vitellarium present on the upper left side of the body were identified as A. foxi. On the host, hepatic lesions limited to the bile ducts and periportal regions, were characterized as chronic-active cholangitis, biliary hyperplasia, and fibrosis. This is the first report of A. foxi parasitizing C. brachyurus, demonstrating that this parasite has no host specificity and can be widely distributed. A. foxi lesions noted in C. brachyurus are similar to those noted in various other mammalian hosts.
- Published
- 2018
12. Transferência de Aprendizado por Reforçoo em Problemas de Otimização Combinatória
- Author
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C. Ottoni, André Luiz, primary, S. de Oliveira, Marcos, additional, C. R. de Oliveira, Daniela, additional, and G. Nepomuceno, Erivelton, additional
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- 2020
- Full Text
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13. A hybrid path-planning strategy for mobile robots with limited sensor capabilities
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Kevin Braathen de Carvalho, Guilherme C. R. de Oliveira, and Alexandre Santos Brandao
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0209 industrial biotechnology ,Computer science ,Tangential escape ,Real-time computing ,02 engineering and technology ,global and local planner ,lcsh:Chemical technology ,Biochemistry ,Article ,Analytical Chemistry ,Task (project management) ,020901 industrial engineering & automation ,Obstacle avoidance ,0202 electrical engineering, electronic engineering, information engineering ,Hybrid strategy ,lcsh:TP1-1185 ,Motion planning ,Electrical and Electronic Engineering ,Instrumentation ,path planning ,Path planning ,tangential escape ,SIMPLE (military communications protocol) ,hybrid strategy ,Mobile robot ,Atomic and Molecular Physics, and Optics ,A* search ,Path (graph theory) ,020201 artificial intelligence & image processing ,Global and local planner - Abstract
This paper introduces a strategy for the path planning problem for platforms with limited sensor and processing capabilities. The proposed algorithm does not require any prior information but assumes that a mapping algorithm is used. If enough information is available, a global path planner finds sub-optimal collision-free paths within the known map. For the real time obstacle avoidance task, a simple and cost-efficient local planner is used, making the algorithm a hybrid global and local planning solution. The strategy was tested in a real, cluttered environment experiment using the Pioneer P3-DX and the Xbox 360 kinect sensor, to validate and evaluate the algorithm efficiency.
- Published
- 2019
14. Local Planning Using Obstacle Estimation and Tangential Escape
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Alexandre Santos Brandao, Guilherme C. R. de Oliveira, and Kevin Braathen de Carvalho
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0209 industrial biotechnology ,Robot kinematics ,Smoothness ,Computer science ,Reliability (computer networking) ,Work (physics) ,02 engineering and technology ,020901 industrial engineering & automation ,Control theory ,Obstacle ,Linear regression ,Path (graph theory) ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,MATLAB ,computer ,computer.programming_language - Abstract
This work proposes a obstacle estimation algorithm to improve the Tangential Escape Algorithm performance on low cost platforms that have spread sensors. This estimation is done using sensor measurements and linear regression to obtain a first order equation and with its inclination the deviation problem of the Tangential Escape is corrected. Filters are also implemented in order to increase the reliability of the obstacle estimation. Simulations were done to validate the this works proposal using ARIA library integrated with MatLab and MobileSim. Results showed a clear improvement on the path smoothness.
- Published
- 2018
15. Porque nascem os espinhos
- Author
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Ronaldo C. R. de Oliveira and Ronaldo C. R. de Oliveira
- Abstract
Porque nascem os espinhos? Essa profunda pergunta está encravada no coração de muitas pessoas. Deus nos deu um presente maravilhoso que foi a nossa vida, mas ao trilhar a grande jornada nesse mundo, enfrentamos terríveis tempestades, frustrações, decepções, traumas, pecados e marcas que afetaram nossas vidas para sempre. Encontrar a resposta para essa pergunta é libertador. Milhões de pessoas nesse mundo estão andando de cabeça baixa, criando mecanismos de defesa para sufocar as feridas, que consciente ou inconscientemente, continuam sangrando, deixando um rastro de dor por onde passam. Mas porque ler um livro sobre espinhos? Porque é bem provável que nesse exato momento exista algum espinho em sua vida, ferindo e sendo ferido, direta ou indiretamente, te afastando do pleno potencial e da vida abundante que Deus tem para você. O autor desse livro, de uma forma inspiradora, te leva a uma viagem pela estrada das escrituras sagradas, com metáforas e ilustrações cativantes, em busca de respostas para sanar a ferida. Tive o privilégio de acompanhar o autor em seu caminhar de cura, libertação e perdão. Em meio a lágrimas, quebrantamento e dor, eu o vi trilhando o caminho de volta ao jardim. Tenho plena tranquilidade em recomendar esse leitura, pois não se trata de princípios teóricos, mas o caminhar real, prático e verdadeiro, de quem já passou por essa estrada e sabe do que está falando. Meu coração se encheu de emoção quando ouvi o Ronaldo dando o seu testemunho de vida e agora explode de alegria ao ler esse livro, ainda mais pela honra de escrever esse prefácio. Pronto para uma viagem de cura? Então abra o seu coração e deixe o Espírito Santo te guiar, página a página, nessa jornada que o levará de volta ao jardim. Boa leitura!!!
- Published
- 2019
16. Agreement between dietary intake of older adults and proxy respondents assessed by a food frequency questionnaire
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Ivone Gonçalves, D. M. Lobo Marchioni, Silvia Regina Dias Médici Saldiva, L. Bassani, C. R. de Oliveira Sales, and A. L. da Silva Castro
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Adult ,Male ,0301 basic medicine ,Gerontology ,Concordance ,Medicine (miscellaneous) ,Diet Surveys ,Diet Records ,Food group ,Eating ,03 medical and health sciences ,0302 clinical medicine ,Vegetables ,Humans ,Medicine ,Ingestion ,030212 general & internal medicine ,Bland–Altman plot ,Aged ,Aged, 80 and over ,030109 nutrition & dietetics ,Nutrition and Dietetics ,business.industry ,Fatty Acids ,food and beverages ,Food frequency questionnaire ,Middle Aged ,Dietary Fats ,Diet ,Fruit ,Respondent ,ADULTOS ,Female ,Dairy Products ,Geriatrics and Gerontology ,Energy Intake ,business ,Kappa ,Demography - Abstract
To evaluate the degree of agreement of dietary intake reported by the patient subject with the dietary intake reported by a respondent (a next-of-kin or a caregiver), collected by a validated Food Frequency Questionnaire (FFQ). 126 adults, both sexes, the average age was 65.9 years for patients and 54.4 years for respondents. They were recruited from the General Practice Clinic at the Clinical Hospital of Sao Paulo (AGD-FMUSP). The agreement between the responses given by patients and respondents was assessed using Spearman, weighted Kappa and Bland Altman tests. The analysis for accuracy between responses (Spearman test) showed a moderate degree of agreement (0.31-0.39) for Energy, Total fat, Total Saturated Fatty Acids (SFA), Total Monounsaturated Fatty Acids (MUFA). Regarding food groups a moderate agreement was found for the majority of the foods (fruits (0.30), dairy products (0.50), natural juices (0.45), beans (0.48), butter/margarine (0.55), coffee (0.41) and soda (0.45), with the exception of vegetables (0.12) and rice (0.63). The ingestion differences did not exceeded the limit of the two standard deviations for the majority of the pairs (Bland Altman). A respondent subsample composed only of husband/wives (N = 36) revealed a moderate agreement concordance for most macronutrients studied (0.30 - 0.58), except polyunsaturated fats (0.25). The results of this study show that, the FFQ may be used in cases where is impossible to get the answers directly from the patients.
- Published
- 2016
17. Context-Aware Routing in Delay and Disruption Tolerant Networks
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Edelberto Silva, Etienne C. R. de Oliveira, Débora C. Muchaluat-Saade, Célio Albuquerque, Igor M. Moraes, Juliano Fischer Naves, and Diego Passos
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Routing protocol ,Zone Routing Protocol ,Dynamic Source Routing ,Static routing ,Computer Networks and Communications ,business.industry ,Computer science ,Distributed computing ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Wireless Routing Protocol ,020206 networking & telecommunications ,020302 automobile design & engineering ,02 engineering and technology ,Routing Information Protocol ,Distance-vector routing protocol ,0203 mechanical engineering ,Link-state routing protocol ,Hardware and Architecture ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,business ,Computer network - Abstract
In this paper, we analyze the problem of context adaptation in delay and disruption tolerant networks (DTNs). Initially, we performed experiments with well-known routing protocols to evaluate how much distinct configurations impact their performance. The results show that the performance is highly configuration dependent and improper configuration can lead to a performance up to 506.6 % worse than the best configuration tested. This motivates us to propose CARTOON (context-aware routing protocol for opportunistic networks), a novel routing protocol for DTNs based on the concept of context-adaptation. We evaluate CARTOON through simulations and the results show that our propose outperformed other well-known protocols, exhibiting results that are, on average, at 95 % of the computed optimum delivery rate.
- Published
- 2016
18. A hybrid strategy for robot navigation in semi-structured environments
- Author
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Kevin Braathen de Carvalho, Guilherme C. R. de Oliveira, and Alexandre Santos Brandao
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0209 industrial biotechnology ,Occupancy grid mapping ,Computer science ,Distributed computing ,Probabilistic logic ,Mobile robot ,02 engineering and technology ,Task (project management) ,020901 industrial engineering & automation ,Obstacle ,Obstacle avoidance ,0202 electrical engineering, electronic engineering, information engineering ,Robot ,020201 artificial intelligence & image processing ,Collision avoidance - Abstract
Autonomous mobile robots should be able to navigate on different types of environments. Some strategies deals with the navigation problem by taking into consideration only the obstacle avoidance task, adopting a reactive behavior. Others, at cost of increased hardware processing, look for optimal paths that must be replanned once an obstacle appears in the planned path. The proposal of this paper is to integrate the A∗ search and obstacle avoidance tangential escape algorithms, in order to overcome the A∗ limitations in non-static environments. Instead of calculating a new route to avoid collisions with unexpected obstacles, as in most popular solutions in the literature, the robot perform deviations while it tries to keep on the planned route. The strategy also uses the robots sensor data for mapping the environment in an Occupancy Grid, in order to navigate deliberatively. Numerical simulations validate the proposal.
- Published
- 2018
19. Exploratory Learning with Convolutional Autoencoder for Discrimination of Architectural Distortion in Digital Mammography.
- Author
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C. R. de Oliveira, Helder, Melo, Carlos F. E., Catani, Juliana H., de Barros, Nestor, and da Costa Vieira, Marcelo A.
- Published
- 2019
- Full Text
- View/download PDF
20. Morphological, chemical and mechanical characteristics of an anodic coating on stainless steel
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W A de Almeida Macedo, R M R Junqueira, A P de Andrade Manfridini, R de Mendonça, and C R de Oliveira Loureiro
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Materials science ,Anodizing ,Abrasion (mechanical) ,Metallurgy ,Oxide ,chemistry.chemical_element ,Surfaces and Interfaces ,engineering.material ,Nanoindentation ,Condensed Matter Physics ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Chromium ,chemistry ,X-ray photoelectron spectroscopy ,Coating ,Materials Chemistry ,engineering ,Layer (electronics) - Abstract
Anodic interference films were grown on stainless steel by an electrochemical process in a 70 g L−1 CrO3+500 g L−1 H2SO4 solution at temperatures of 25–75°C. The aim of this research was to assess the influence of temperature on characteristics of this coating. The morphology of the films was assessed through atomic force microscopy, the chemical composition was assessed by X-ray photoelectron spectroscopy, while the mechanical characteristics were assessed by resistance to abrasion wear and nanohardness. The roughness of the films grown at 25°C is less than that of the other temperatures. No significant difference regarding the porosity of the films was detected. A chromium hydroxide was observed on the top of the oxide layer grown on stainless steel. The steel coloured at 75°C presented a lesser hardness compared to the samples grown at 25, 35 and 55°C. The wear resistance increased as the temperature of the film’s growth rose, which was inversely proportional to the hardness.
- Published
- 2013
21. Method for simulating dose reduction in digital mammography using the Anscombe transformation
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Lucas R, Borges, Helder C R de, Oliveira, Polyana F, Nunes, Predrag R, Bakic, Andrew D A, Maidment, and Marcelo A C, Vieira
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Models, Anatomic ,Anscombe transformation ,Phantoms, Imaging ,quantum noise ,Radiation Dosage ,dose reduction ,DIAGNOSTIC IMAGING (IONIZING AND NON-IONIZING) ,digital mammography ,Linear Models ,Humans ,Computer Simulation ,Breast ,Artifacts ,Algorithms ,Research Articles ,Mammography - Abstract
Purpose: This work proposes an accurate method for simulating dose reduction in digital mammography starting from a clinical image acquired with a standard dose. Methods: The method developed in this work consists of scaling a mammogram acquired at the standard radiation dose and adding signal-dependent noise. The algorithm accounts for specific issues relevant in digital mammography images, such as anisotropic noise, spatial variations in pixel gain, and the effect of dose reduction on the detective quantum efficiency. The scaling process takes into account the linearity of the system and the offset of the detector elements. The inserted noise is obtained by acquiring images of a flat-field phantom at the standard radiation dose and at the simulated dose. Using the Anscombe transformation, a relationship is created between the calculated noise mask and the scaled image, resulting in a clinical mammogram with the same noise and gray level characteristics as an image acquired at the lower-radiation dose. Results: The performance of the proposed algorithm was validated using real images acquired with an anthropomorphic breast phantom at four different doses, with five exposures for each dose and 256 nonoverlapping ROIs extracted from each image and with uniform images. The authors simulated lower-dose images and compared these with the real images. The authors evaluated the similarity between the normalized noise power spectrum (NNPS) and power spectrum (PS) of simulated images and real images acquired with the same dose. The maximum relative error was less than 2.5% for every ROI. The added noise was also evaluated by measuring the local variance in the real and simulated images. The relative average error for the local variance was smaller than 1%. Conclusions: A new method is proposed for simulating dose reduction in clinical mammograms. In this method, the dependency between image noise and image signal is addressed using a novel application of the Anscombe transformation. NNPS, PS, and local noise metrics confirm that this method is capable of precisely simulating various dose reductions.
- Published
- 2016
22. Multi-locus DNA sequencing of Toxoplasma gondii isolated from Brazilian pigs identifies genetically divergent strains
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F. C. R. de Oliveira, E. Frazão-Teixeira, Natarajan Sundar, Michael E. Grigg, and Jitender P. Dubey
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Genotype ,Swine ,Highly pathogenic ,Locus (genetics) ,Polymerase Chain Reaction ,Article ,DNA sequencing ,law.invention ,Mice ,law ,parasitic diseases ,Genetic variation ,Animals ,Allele ,Polymerase chain reaction ,Genetics ,Base Sequence ,General Veterinary ,biology ,Genetic Variation ,Toxoplasma gondii ,General Medicine ,DNA, Protozoan ,biology.organism_classification ,Virology ,Toxoplasmosis, Animal ,Cats ,Parasitology ,Toxoplasma ,Brazil ,Polymorphism, Restriction Fragment Length - Abstract
Five Toxoplasma gondii isolates (TgPgBr1-5) were isolated from hearts and brains of pigs freshly purchased at the market of Campos dos Goytacazes, Northern Rio de Janeiro State, Brazil. Four of the five isolates were highly pathogenic in mice. Four genotypes were identified. Multi-locus PCR-DNA sequencing showed that each strain possessed a unique combination of archetypal and novel alleles not previously described in South America. The data suggest that different strains circulate in pigs destined for human consumption from those previously isolated from cats and chickens in Brazil. Further, multi-locus PCR-RFLP analyses failed to accurately genotype the Brazilian isolates due to the high presence of atypical alleles. This is the first report of multi-locus DNA sequencing of T. gondii isolates in pigs from Brazil.
- Published
- 2011
23. Packet Scheduling and Discard Policies for Diffusion Control in Delay and Disruption Tolerant Networks
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Diego Passos, Etienne C. R. de Oliveira, Henrique Bueno, and Célio Albuquerque
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Dynamic Source Routing ,Equal-cost multi-path routing ,Computer science ,business.industry ,Distributed computing ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,DSRFLOW ,Geographic routing ,Source routing ,Link-state routing protocol ,Optimized Link State Routing Protocol ,Destination-Sequenced Distance Vector routing ,business ,Computer network - Abstract
A Disruption Tolerant Network (DTN) is charac- terized by scenarios where end-to-end connectivity is rarely available. Hence, in such networks, the use of existing ad hoc routing protocols may result on poor performance, since they rely on the existence of an end-to-end path between the source and destination nodes. This paper proposes a DTN routing strategy called DRAIN. Differently from other proposals based on Epidemic routing, DRAIN considers realistic scenarios where nodes' buffer capacity and link bandwidth are limited. Our performance analysis demonstrates the inefficacy of the Epidemic approach in scenarios under such constraints. However, through a controlled packet diffusion and a quantitative packet deliver estimate, DRAIN is able to present good delivery rates in the same conditions, as well as a lower consumption of network resources.
- Published
- 2008
24. PRODUÇÃO DE BIODISEL POR CATÁLISE HETEROGÊNEA USANDO ÓXIDO MISTO CaO-CeO2 COMO CATALISADOR
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V. L. Cardoso, Roni de Carvalho Fernandes, M. H. M. Reis, Mariana Martins, and C. R. de Oliveira
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Chemistry - Published
- 2015
25. Protective effects of the angiotensin type 1 receptor antagonist losartan in infection-induced and arthritis-associated alveolar bone loss
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Danielle G. Souza, Adriana Pedrosa Moura, Sandra Y. Fukada, M.M. Teixeira, C. R. de Oliveira, Kátia D. Silveira, Celso Martins Queiroz-Junior, T.A. da Silva, Mila Fernandes Moreira Madeira, Frederico Marianetti Soriani, and Abilio Jose de Oliveira Ferreira
- Subjects
Male ,Serum ,musculoskeletal diseases ,medicine.medical_specialty ,Knee Joint ,medicine.drug_class ,Alveolar Bone Loss ,Anti-Inflammatory Agents ,Arthritis ,Aggregatibacter actinomycetemcomitans ,Losartan ,Receptor, Angiotensin, Type 1 ,OSTEOBLASTO ,Mice ,Osteoprotegerin ,Osteoclast ,Internal medicine ,Maxilla ,medicine ,Animals ,Dental alveolus ,Mice, Inbred BALB C ,Angiotensin II receptor type 1 ,biology ,Histocytochemistry ,business.industry ,medicine.disease ,Receptor antagonist ,Mice, Inbred C57BL ,RAW 264.7 Cells ,Endocrinology ,medicine.anatomical_structure ,RANKL ,biology.protein ,Periodontics ,Pasteurellaceae Infections ,business ,medicine.drug - Abstract
Background and Objective The angiotensin type 1 (AT1) receptor has been implicated in the pathogenesis of inflammatory bone disorders. This study aimed to investigate the effect of an AT1 receptor antagonist in infection-induced and arthritis-associated alveolar bone loss in mice. Material and Methods Mice were subjected to Aggregatibacter actinomycetemcomitans oral infection or antigen-induced arthritis and treated daily with 10 mg/kg of the prototype AT1 antagonist, losartan. Treatment was conducted for 30 d in the infectious condition and for 17 d and 11 d in the preventive or therapeutic regimens in the arthritic model, respectively. The mice were then killed, and the maxillae, serum and knee joints were collected for histomorphometric and immunoenzymatic assays. In vitro osteoclast assays were performed using RAW 264.7 cells stimulated with A. actinomycetemcomitans lipopolysacharide (LPS). Results Arthritis and A. actinomycetemcomitans infection triggered significant alveolar bone loss in mice and increased the levels of myeloperoxidase and of TRAP+ osteoclasts in periodontal tissues. Losartan abolished such a phenotype, as well as the arthritis joint inflammation. Both arthritis and A. actinomycetemcomitans conditions were associated with the release of tumor necrosis factor alpha (TNF-α), interferon-gamma, interleukin-17 and chemokine (C-X-C motif) ligand 1 and an increased RANKL/osteoprotegerin ratio in periodontal tissues, but such expression decreased after losartan treatment, except for TNF-α. The therapeutic approach was as beneficial as the preventive one. In vitro, losartan prevented LPS-induced osteoclast differentiation and activity. Conclusion The blockade of AT1 receptor exerts anti-inflammatory and anti-osteoclastic effects, thus protecting periodontal tissues in distinct pathophysiological conditions of alveolar bone loss.
- Published
- 2015
26. Classical electronic autoionization under molecular oscillations
- Author
-
C. R. de Oliveira and Alejandro López-Castillo
- Subjects
Physics ,General Mathematics ,Applied Mathematics ,General Physics and Astronomy ,Statistical and Nonlinear Physics ,Electron ,Reduced mass ,symbols.namesake ,Autoionization ,Quantum mechanics ,Molecular vibration ,Rydberg formula ,symbols ,Molecule ,Hamiltonian (quantum mechanics) ,Quantum - Abstract
We study the influence of the molecular oscillations over a classical Rydberg electron via an approximated periodic driven Hamiltonian with one degree of freedom. We consider several approximations in order to obtain estimates for the chaos border, the diffusion prevision and the appearance of quantum localization. The model is adapted to some classes of molecules and infers conditions for the autoionization of generic molecular systems as function of the vibrational frequency, the eccentricity of the trajectories and nuclear reduced mass.
- Published
- 2004
27. Macroscopic lesions of the ventriculus of Rhea americana , Linnaeus, 1758 (Aves: Rheidae) naturally infected by Sicarius uncinipenis (Molin, 1860) (Nematoda: Habronematidae)
- Author
-
F. C. R. de Oliveira and Nicole Brand Ederli
- Subjects
Male ,Gastrointestinal tract ,biology ,Ventriculus ,Bird Diseases ,Rheiformes ,Zoology ,Parasitism ,Spirurida Infections ,Sicarius ,Anatomy ,biology.organism_classification ,Parasite load ,Nematode ,Stomach, Avian ,Captive breeding ,Animals ,Parasitology ,Rheidae ,Female ,Proventriculus ,Ecology, Evolution, Behavior and Systematics ,Spirurida - Abstract
There are few studies concerning the parasites of rheas. However, parasitism is the major cause of the limited success in captive breeding of these birds. Deletrocephalus dimidiatus, Deletrocephalus cesarpintoi, Paradeletrocephalus minor, and Sicarius uncinipenis are the most prevalent nematode species affecting these birds, but the lesions caused by these parasites have not been previously reported. Four adult rheas were necropsied to determine the presence or absence of gross lesions within the gastrointestinal tract, associated with parasitic infection. Two rheas parasitized by S. uncinipenis had ulcers on the koilin layer or had parasites penetrating this layer, resulting in widespread necrosis and hemorrhagic areas, whereas the 2 nonparasitized birds did not present lesions. The degree of injury was proportional to the parasitic load found in the birds. Thus, high parasitic loads can result in necrosis of the ventriculus, which may contribute to the death of birds, resulting in economic losses in the rural production of these birds.
- Published
- 2014
28. Autocorrelation Scaling and Fourier Transform of Non-Autonomous Systems
- Author
-
C. R. de Oliveira
- Subjects
Nuclear and High Energy Physics ,Autocorrelation ,Mathematical analysis ,Hilbert space ,Statistical and Nonlinear Physics ,Measure (mathematics) ,Fractional Fourier transform ,symbols.namesake ,Fourier transform ,Quantum harmonic oscillator ,symbols ,Quantum system ,Quantum Fourier transform ,Mathematical Physics ,Mathematics - Abstract
Upper bounds for the (strong) Fourier transform,of a rather general sequence of unitary operators, are related to the uniform α-Holder continuity of its autocorrelation measure. It is a natural generalization of the "Dynamical Bombieri-Taylor Conjecture". Immediate applications include driven quantum systems, classical and quantum harmonic oscillators, and non-autonomous twisted generalized random walks in Hilbert spaces.
- Published
- 2000
29. Context adaptation in delay and disruption tolerant networks
- Author
-
Etienne C. R. de Oliveira, C. V. N. de Albuquerque, Débora C. Muchaluat-Saade, and Edelberto Silva
- Subjects
Routing protocol ,Zone Routing Protocol ,Distance-vector routing protocol ,Link-state routing protocol ,Context adaptation ,Computer science ,business.industry ,Distributed computing ,Interior gateway protocol ,Context (language use) ,business ,Mobile device ,Computer network - Abstract
Delay and disruption tolerant network scenarios present contrasting traits that may cause significant variation in the performance of routing protocols. In this work, the evaluation of protocols RAPID, MaxProp, PRoPHET and Spray and Wait on three different scenarios with contrasting characteristics enabled the analysis of the impact of these fluctuations in performance and the verification that parameterizable protocols are able to boost substantially the performance. In addition, we add to PRoPHET the ability to adapt to the scenarios characteristics (context), depending on the network density and message load. Simulations with real traces of mobile devices have proven its effectiveness, increasing performance by up to 19.96% compared to the standard configuration.
- Published
- 2012
30. Numerical Study of the Long-Time Behaviour of Quantum Systems Driven by Thue-Morse Forces. Application to Two-Level Systems
- Author
-
C. R. de Oliveira
- Subjects
Physics ,Conjecture ,Computation ,Autocorrelation ,General Physics and Astronomy ,Polarization (waves) ,Morse code ,law.invention ,symbols.namesake ,Amplitude ,Fourier transform ,Classical mechanics ,law ,symbols ,Quantum - Abstract
We study quantum systems with Thue-Morse kicked Hamiltonians. Very simple and effective algorithms for the numerical computation of autocorrelation functions, polarization fluctuations and decaying properties of Fourier amplitude intensity are presented. We study in detail the case of a two-level system which has interest per se; on account of the numerical results we conjecture that generically this system has a singular continuous-like dynamical evolution.
- Published
- 1995
31. On kicked systems modulated along the Thue-Morse sequence
- Author
-
C R de Oliveira
- Subjects
Sequence ,Dirac (software) ,Mathematical analysis ,Time evolution ,Short-time Fourier transform ,General Physics and Astronomy ,Thue–Morse sequence ,Statistical and Nonlinear Physics ,Fractional Fourier transform ,symbols.namesake ,Fourier transform ,Fourier analysis ,symbols ,Mathematical Physics ,Mathematics - Abstract
We give necessary conditions for the Fourier transform of the time evolution operator of kicked systems, modulated along the Thue-Morse sequence, to present Dirac's delta functions. The case of two-level systems is analysed in detail and it is found-based on the trace map and numerical investigations-that generically its time evolution has no quasi-periodic component.
- Published
- 1994
32. From Power-Localized to Extended Quasi-Energy Eigenstates in a Quantum Periodically Driven System
- Author
-
C. R. de Oliveira, G. Casati, and I. Guarneri
- Subjects
Nonlinear Sciences::Chaotic Dynamics ,Physics ,Delocalized electron ,Quantum mechanics ,Chaotic ,General Physics and Astronomy ,Monochromatic color ,Quantum ,Energy (signal processing) ,Eigenvalues and eigenvectors ,Classical limit ,Power (physics) - Abstract
We study the dynamics of a quantum particle in a triangular potential well under a monochromatic driving. We provide a purely quantal theory that accounts for the transition from localization to delocalization, without making reference to the chaotic transition occurring in the classical limit.
- Published
- 1994
33. NECTAR
- Author
-
Etienne C. R. de Oliveira and Célio Albuquerque
- Subjects
Routing protocol ,Moment (mathematics) ,business.industry ,Computer science ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Wireless ,Nectar ,business ,Protocol (object-oriented programming) ,Computer network - Abstract
There are a number of scenarios where connectivity is intermittent, and a given destination may not be reachable at the moment a message is sent. Networks with these characteristics are known as Delay and Disruption Tolerant Networks (DTN). The NECTAR protocol proposed in this article is based on the contacts history in order to create a Neighborhood Index and then determine the most appropriated route for DTNs. Simulations performed with real data retrieved from mobile and wireless environments at Dartmouth College in scenarios where the occurrence of highly-partitioned networks is frequent, and with the presence of resource constrained nodes show that NECTAR is able to deliver more messages than Epidemic and PROPHET protocols with lower consumption of network resources.
- Published
- 2009
34. [Swine cryptosporidiosis related to production systems in the state of Rio de Janeiro]
- Author
-
Vagner R S, Fiuza, Rachel I J, Cosendey, and Francisco C R, De Oliveira
- Subjects
Swine Diseases ,Swine ,Oocysts ,Animals ,Cryptosporidiosis ,Brazil - Abstract
The purpose of this study was to verify the prevalence of cryptosporidiosis in swine farms of familiar and technical production systems, located in the North and Northwest Regions of the State of Rio de Janeiro. A total of 103 fecal samples of different swines were collected, proceeding from 10 farms, of which five were familiar and five technical. For the diagnosis, the modified concentration by sedimentation technique with posterior staining by modified Ziehl-Neelsen was used. Forty and 29.3% of prevalence were observed in the familiar and technical farms respectively, and they were not statistically different. The parasitism occurs in both production systems, probably due to an absence of previous diagnosis of the illness. After morfometric and morphological analysis and statistical study of correlation of the 87 oocysts found, it was suggested that exists more than one species of Cryptosporidium spread in the properties, and they are common to each of the production systems. This hypothesis needs to be confirmed through studies of molecular biology, to characterize the species.
- Published
- 2008
35. Sarcocystis lindsayi-like (Apicomplexa: Sarcocystinae) of the opossum (Didelphis aurita) from Southeastern Brazil
- Author
-
Cristiane S, Stabenow, Francisco C R, De Oliveira, George R, Albuquerque, and Carlos Wilson G, Lopes
- Subjects
Animals ,Sarcocystis ,Opossums ,Melopsittacus ,Brazil - Abstract
Sporocysts of Sarcocystis were obtained from intestinal scrapings of three out of five opossums (Didelphis aurita) trapped in the southeastern region, of the State of Rio de Janeiro, Brazil. Fifteen caged budgerigars (Melopsittacus undulatus) received, orally, twenty-six sporocysts in 500 mL PBS, but only five belonging to one of the groups developed clinical signs, that consisted of anorexia, lethargy, ruffled feathers and dyspnoea, and parasitism in tissues. Two of the five budgerigars died on the 25th and 29th days after infection (DAI). The other three budgerigars were posted on the 30th DAI. In all the five infected birds were observed meronts in the capillaries of the lungs and cysts in muscles, mainly in the tongue and legs.
- Published
- 2008
36. Cantor singular continuous spectrum for operators along interval exchange transformations
- Author
-
M. Cobo, C. Gutierrez, and C. R. de Oliveira
- Subjects
37B10 ,Mathematics::Dynamical Systems ,Applied Mathematics ,General Mathematics ,Continuous spectrum ,Mathematical analysis ,Spectrum (functional analysis) ,FOS: Physical sciences ,Cantor function ,Mathematical Physics (math-ph) ,Lebesgue integration ,37B05 ,Cantor set ,Null set ,symbols.namesake ,DINÂMICA TOPOLÓGICA ,symbols ,Embedding ,Interval (graph theory) ,47B36 ,Mathematical Physics ,47B37 ,Mathematics - Abstract
It is shown that Schrödinger operators, with potentials along the shift embedding of Lebesgue almost every interval exchange transformations, have Cantor spectrum of measure zero and pure singular continuous for Lebesgue almost all points of the interval.
- Published
- 2008
37. Management Issues on Wireless Mesh Networks
- Author
-
R.L. Valle, Diego Passos, Etienne C. R. de Oliveira, Célio Albuquerque, Jairo Leite Duarte, and Débora C. Muchaluat-Saade
- Subjects
Wireless mesh network ,business.industry ,Computer science ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Access control ,Topology (electrical circuits) ,The Internet ,Performance measurement ,business ,Network topology ,Search and rescue ,Municipal wireless network ,Computer network - Abstract
Wireless mesh networks (WMN) are emerging as a flexible and low-cost alternative to provide digital inclusion through multi-hop communications, supporting applications from last-mile Internet delivery, search and rescue, home networking to distributed gaming. Managing increasingly large and unplanned WMNs has many challenges. This paper has the primary goal of raising management issues in wireless mesh networks. Furthermore this work documents the management solutions deployed by the ReMesh project 1 in terms of network configuration, topology view, access control, performance measurement and statistics.
- Published
- 2007
38. Utilização de fenbendazole e da associação febantel, pamoato de pirantel e praziquantel no controle de oxiurídeos em gerbis
- Author
-
Francimar Fernandes Gomes, Vagner Ricardo da Silva Fiuza, R.S. Toledo, Helaíne Haddad Simões Machado, F. C. R. de Oliveira, Laboratoire Interdisciplinaire de Recherche en Didactique, Éducation et Formation (LIRDEF), Université Paul-Valéry - Montpellier 3 (UPVM)-Université de Montpellier (UM), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), and Université de Montpellier (UM)-Université Paul-Valéry - Montpellier 3 (UPVM)
- Subjects
0303 health sciences ,[SDV.BA.MVSA]Life Sciences [q-bio]/Animal biology/Veterinary medicine and animal Health ,General Veterinary ,Traditional medicine ,anthelmintic ,business.industry ,[SDV]Life Sciences [q-bio] ,030231 tropical medicine ,Pharmacology ,jirds ,3. Good health ,Praziquantel ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Fenbendazole ,business ,ComputingMilieux_MISCELLANEOUS ,gerbis ,anti-helmíntico ,030304 developmental biology ,medicine.drug - Abstract
Eighteen jirds were equally distributed in two treated and one control groups. The commercial products to the fenbendazole base (10mg) and the association of febantel (1.5mg), pirantel (1.44mg) and praziquantel (0.5mg) were orally administred in the concentration of 0.1ml in each group. The effectiveness of febendazole against oxiurids was 81.8%, 65.0 and 38.7% and for the association of febantel, pirantel and praziquantel was 72.7%, 73.8% and 51.0% on days 7, 14 and 21, respectively. Three applications of that dose of the tested medications, within intervals of 10 days, associated to hygiene, are recommended.
- Published
- 2007
39. [Species from genus Eimeria observed in domestic rabbit (Oryctolagus cuniculus) feces raised at the Municipality of Campos dos Goytacazes in the State of Rio de Janeiro, Brazil]
- Author
-
Adriana J, de Almeida, Friederike L, Mayen, and Francisco C R, de Oliveira
- Subjects
Feces ,Animals ,Eimeria ,Rabbits ,Animal Husbandry ,Brazil - Abstract
This study was designed to identify species of the genus Eimeria from eleven rabbit meat breeders from Campos dos Goytacazes. Fecal samples were collected from rabbits with different health conditions and consintence of feces. The following species of Eimeria were identified: E. perforans; E. magna; E. coecicola; E. irresidua; E. media; E. flavescens; E. nagpurensis; E. intestinalis, E. exigua and E. stiedae. Parasites from this genus were detected in 81.82% (9) of the rabbit meat production sites, regardless of the management and hygiene conditions. In all cases the infection was always caused from more than one species of Eimeria.
- Published
- 2006
40. Antiprotozoal effect of crude extracts and flavonoids isolated from Chromolaena hirsuta (asteraceae)
- Author
-
S H, Taleb-Contini, M J, Salvador, J M F, Balanco, S, Albuquerque, and D C R, de Oliveira
- Subjects
Flavonoids ,Leishmania ,Plant Leaves ,Parasitic Sensitivity Tests ,Plant Extracts ,Chromolaena ,Trypanosoma cruzi ,Antiprotozoal Agents ,Animals ,Flowers ,Phytotherapy - Abstract
Phytochemical study of Chromolaena hirsuta (Hook.Arn.) R. KingH. Robinson crude extract (collected in Furnas, MG-Brasil) produced fifteen flavonoids, two triterpenes and five steroids. IR, UV,(1)H and (13)C NMR spectroscopy and GC analysis were used for the identification of these compounds. The dichloromethanic and ethanolic crude extracts (flowers and leaves) and six flavonoids isolated from this specie have been assayed for antiprotozoal activity against tripomastigote forms of Trypanosoma cruzi and promastigote forms of Leishmania amazonensis. The crude extracts significantly reduced the viability of T. cruzi and Leishmania amazonensis, and the six flavonoids showed considerable antiproliferative effect of development of two parasites evaluated. This is the fi rst report of antiprotozoal activity of extracts of C. hirsuta.
- Published
- 2004
41. [Osteoblastoma: analysis of the treatment of 24 cases]
- Author
-
A T, Croci, O P, de Camargo, R J, de Freitas, N R, de Oliveira, M, Etchebehere, and C R, de Oliveira
- Subjects
Adult ,Male ,Radiography ,Adolescent ,Child, Preschool ,Cervical Vertebrae ,Humans ,Bone Neoplasms ,Female ,Osteoblastoma ,Humerus ,Child - Abstract
The authors study 24 patients with the histologic diagnosis of osteoblastoma treated from 1953 to 1996, with a mean follow-up of 33.4 months. Two were considered as a malignant osteoblastoma. Twenty-two cases were operated, and in 2 of these was performed only a selective embolization to pelvic and spine localization. It was discussed clinical and radiographic aspects and the response to treatment. It was obtained 20 good and 4 poor results.
- Published
- 1997
42. Apoptosis as a mechanism of cell death induced by different chemotherapeutic drugs in human leukemic T-lymphocytes
- Author
-
C P, da Silva, C R, de Oliveira, M, da Conceição, and P, de Lima
- Subjects
Programmed cell death ,Time Factors ,Daunorubicin ,T-Lymphocytes ,Antineoplastic Agents ,Apoptosis ,Cell Count ,Pharmacology ,Biology ,Biochemistry ,Jurkat cells ,medicine ,Cytotoxic T cell ,Humans ,Viability assay ,Cell Death ,Dose-Response Relationship, Drug ,Methotrexate ,Doxorubicin ,Cancer research ,DNA fragmentation ,Intracellular ,medicine.drug - Abstract
The involvement of apoptosis in the mechanism of cell death induced by six clinically relevant anticancer drugs [methotrexate (MTX), doxorubicin (ADR), daunorubicin (DNR), vincristine (VCR), 6-mercaptopurine (6MP), and prednisolone (PRD)] in human leukemic T-lymphocytes (CCRF-CEM and Jurkat) was investigated by analysing changes in cell size and morphology, changes in membrane integrity, alterations in [Ca2+]i and induction of DNA fragmentation. MTX, ADR, and DNR showed pronounced dose- and time-dependent cytotoxic effects on both cell lines, whereas cell viability was not considerably reduced by 6MP or PRD. On the other hand, the cytotoxic activity of VCR was much higher on Jurkat cells than on CEM cells. With the exception of 6MP and PRD, all the other compounds induced extensive chromatin condensation, nuclear fragmentation, plasma membrane blebbing, and formation of apoptotic bodies and fragmentation of DNA in both cell lines. Occurrence of DNA fragmentation always preceded loss of membrane integrity. These observation are consistent with cell death being mediated by apoptosis. Significant increases in [Ca2+]i were only observed in CEM cells preincubated with MTX or DNR (10 microM). In contrast, MTX as well as VCR induced a reduction in the basal intracellular Ca2+ concentration in Jurkat T-cells. Although the ability to induce changes in [Ca2+]i correlated with higher cytotoxic potency of the anticancer drugs, a causal relationship between increased [Ca2+] and induction of apoptosis could not be clearly established. These results, therefore, suggest no determinant role for Ca2+ in triggering the process of endonucleolytic cleavage of genomic DNA in these leukemic T-lymphocytes.
- Published
- 1996
43. [Frequency of intestinal helminth eggs in public restrooms in Sorocaba, SP]
- Author
-
T, Aidar Sobrinho, L M, Coelho, S M, de Oliveira, J de T, Martins, J A, Rabello Júnior, C R, de Oliveira, M A, de Puala, M W, Perroud Júnior, and S M, Miyazaki
- Subjects
Male ,Helminths ,Animals ,Humans ,Female ,Toilet Facilities ,Parasite Egg Count ,Brazil - Abstract
Four hundred and five water closets were investigated: 11 located at public squares, 2 at the railroad station, 4 at the bus station, 55 at bars and restaurants, 146 at state schools, 116 at municipal schools, 8 at private schools, 36 at public health centers, 16 at sports centers, 8 at orphanages and 3 at shopping malls. Microscopy slides with adhesive tape were used. The material was obtained by sticking the tape onto the following elements: 4 spots on the toilet seat, internal and external door knobs, latch, faucet handle and discharge valve (push button or pulling string). Out of the 405 water closets studied, 22 (5.43%) were contaminated. Eggs of Ascaris lumbricoides, Ancylostomatidae, Enterobius vermiculares, Taenia sp and Hymenolepis nana were found. In 2 water closets eggs of 2 parasites were found simultaneously.
- Published
- 1995
44. Sparse one-dimensional discrete Dirac operators II: Spectral properties
- Author
-
C. R. de Oliveira, Roberto A. Prado, and S. L. Carvalho
- Subjects
Mathematical analysis ,Dirac (software) ,Statistical and Nonlinear Physics ,Spectral theorem ,Relativistic quantum mechanics ,Operator theory ,Mathematical Operators ,Schrödinger equation ,symbols.namesake ,Spectral asymmetry ,Hausdorff dimension ,symbols ,Mathematical Physics ,Mathematics - Abstract
We study spectral properties of some discrete Dirac operators with nonzero potential only at some sparse and suitably randomly distributed positions. As observed in the corresponding Schrodinger operators, we determine the Hausdorff dimension of its spectral measure and identify a sharp spectral transition from point to singular continuous.
- Published
- 2011
45. Cantor singular continuous spectrum for operators along interval exchange transformations.
- Author
-
M. Cobo, C. Gutierrez, and C. R. de Oliveira
- Published
- 2007
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46. Pharmacological comparison of the vasorelaxant action displayed by kaurenoic acid and pimaradienoic acid.
- Author
-
Carlos R. Tirapelli, Sergio R. Ambrosio, Silvia T. Coutinho, Dionéia C. R. de Oliveira, Fernando B. da Costa, and Ana M. De Oliveira
- Published
- 2005
47. Trypanocidal and antifungal activities of p-hydroxyacetophenone derivatives from Calea uniflora (Heliantheae, Asteraceae).
- Author
-
Andréa Mendes do Nascimento, Marcos José Salvador, Regina Celia Candido, Sérgio de Albuquerque, and Dionéia C. R. de Oliveira
- Published
- 2004
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