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Search Results: 1 - 10 of 199876 matches for " Luiz Ferreira de Souza "
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Dynamical Donwscaling for Railroad Areas in Eastern Amazon and Southeastern Brazil: Current Climate and Near-Future Projections  [PDF]
Everaldo B. De Souza, Bergson C. de Moraes, Douglas B. S. Ferreira, Luiz Gylvan Meira Filho
Atmospheric and Climate Sciences (ACS) , 2014, DOI: 10.4236/acs.2014.42018

We performed a dynamic downscaling using REGCM4 regional model driven by MPI global model for current (1990/2012) and near-future (2015/2039) climate in order to characterize the seasonal rainfall regimes throughout the railroad areas in eastern Amazon and southeastern Brazil. The analysis of observational data for the current climate indicated the existence of pronounced spatial variations in rainfall regime across railroad regions during both the rainy and dry seasons. Although models have presented generalized underestimation, the regional model showed improvements on spatial representation and intensity of the rainfall in comparison with global model results. We reported the future projections taking into account the correction of simulated rainfall by the values of the biases found in each respective seasonal regime, so that the results are expressed by percentage changes of the future (2015/2037) relative to the current climate patterns. For the railroad in eastern Amazon, projections indicate a weak decrease of rainfall of about -15% in the rainy season (January to May), however during the dry season (June to October) are expected drastic reductions between -70% and -90% in south (Carajás in Pará state) and north (Sao Luis in Maranhao state) portions. Conversely, for the railroad in southeast Brazil, model projections point out for an increased rainfall regime during the rainy season (October to February) around +30% to +40% in the east part of the region over the Espírito Santo state.

Organic Reserves in ropical Grasses under Grazing  [PDF]
Mariane Moreno Ferro, Anderson de Moura Zanine, Daniele de Jesus Ferreira, Alexandre Lima de Souza, Luiz Juliano Valério Geron
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.614236
Abstract: Inadequate management in recent times has been considered the main factor contributing to pasture degradation. A major reason for this is related to gross errors of grazing management as a consequence of the lack of knowledge of ecophysiological limits of forage. This review aimed to approach the importance of organic reserves for grasses under grazing. Therefore, the predominant effect of animal grazing is the reduction of leaf area which impacts on carbohydrate and nitrogen reserves and consequently the growth of tillers, leaves and roots. Grass growth after defoliation is related to organic reserves and rate of photosynthesis. The latter is affected by the level of canopy light interception of and by the reminiscent leaf area index. When grazing management is carried out with respect to the physiological limits of grass growth, the rate of dry matter accumulation will be quick and constant. In this aspect, grazing management consists of seeking an efficient balance between plant growth and consumption which will reflect on animal productivity. Therefore, a balance point among frequency and intensity of defoliation must be found to achieve greater animal production concerning the ecophysiological limits of the forage plants. So the challenge will be to find a balance between frequency and intensity of grazing to achieve greater production of animals respecting the eco-physiological limits of forage plants for each forage grass individually.
Structural and Production Characteristics of Piat? Grass Forage Submitted to Levels of Nitrogen  [PDF]
Ronaldo Liberato Dourado, Alexandre Lima de Souza, Anderson de Moura Zanine, Fabio Luiz Buranelo Toral, Daniele de Jesus Ferreira, Joadil Gon?alves de Abreu
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.65075
Abstract: Piatã grass (Brachiaria brizantha cv. Piatã) is a tropical grass cultivating in pasture production system. The aim of this study was to evaluate the effects of nitrogen levels (0, 125, 250, 375 and 500 kg·N·ha-1) on structural characteristics and forage production of Piatã grass. The experiment comprised of twenty grass parcels arranged in randomised completely casualties design. This study was carried out between November of 2007 and April of 2008, with 175 experimental days. A quadratic effect (P < 0.05) was verified for nitrogen dosage on canopy height, final leaf blade length and leaf area index. Nitrogen fertilisation altered the population density of tillers, with estimated maximum value of 955 tillers·m-2 at a nitrogen dose of 357 kg·ha-1. A quadratic effect (P < 0.05) was also verified for nitrogen levels on the production of total and green leaf blade dry matter, with estimated maximum values of 19,253 and 11,548 kg·ha-1·year-1?for nitrogen levels of 411 and 384 kg·ha-1, respectively. However, a considerable portion of forage production obtained by nitrogen addition occurred from stem production. The productions of green leaf blade dry matter, tiller density, leaf blade length and leaf blade index are all variables related to structural aspects and pasture quality, with all attaining their highest values at a mean nitrogen application level of 380 kg·ha-1.
Gripe aviária no Brasil: uma análise econ?mica de equilíbrio geral
Fachinello, Arlei Luiz;Ferreira Filho, Joaquim Bento de Souza;
Revista de Economia e Sociologia Rural , 2010, DOI: 10.1590/S0103-20032010000300003
Abstract: the h5n1 avian influenza virus has been spreading fast over countries and continents in the last years, with a real possibility of reaching brazil. the scope of this paper is to analyze the impacts of three different scenarios of a possible bird flu outbreak in commercial poultry production in brazil, with the aid of a brazilian inter-regional general equilibrium model. results point to a greater negative impact over the production in the southern region, with the correspondent negative impact in the broad regional economies. regions producing substitute goods, on the other hand, would be benefited, due to consumer's substitution towards other meats. actually, the substitution effect caused by the change in consumer's preferences, both domestically and abroad, is found to be the key driver of the regional income and employment changes.
Production of reactive oxygen species during the aerobic and anaerobic exercise
Carine Ferreira de Souza,Luiz Fernandes,Edilson Serpeloni Cyrino
Revista Brasileira de Cineantropometria e Desempenho Humano , 2006,
Abstract: The protective effect of physical exercise against diseases is well established in literature, although it is known that exercising generates free radicals. Despite the mitochondria being the main source of free radicals, the processes of ischemia, inflammation, and reperfusion can also form free radicals. The purpose of this literature review was to investigate the impact of both aerobic and anaerobic physical exercise on the generation of reactive oxygen species (ROS). We verified that cellular and tissue damage by free radicals, caused by lipid peroxidation and inflammation, occurs in both types of physical exercises, especially in high intensity efforts. There are indications that ROS generation during physical exercise cannot be modulated by regular training, however, the cellular environment can increase antioxidant endogenous concentration to compensate for that stress. Moreover, ROS regulation can differently occur in aerobic and anaerobic exercises. Therefore, the control of oxidative stress may be very important, particularly, in anaerobic exercises. RESUMOO efeito protetor do exercício físico contra doen as está bem estabelecido na literatura, embora haja conhecimento de que sua prática gera radicais livres. Apesar de a mitoc ndria ser a principal fonte de radicais livres, os processos de isquemia, inflama o e reperfus o também podem causar forma o de radicais livres. Apartir de uma ampla revis o da literatura, o objetivo deste estudo foi investigar o impacto do exercício físico sob condi es de aerobiose e anaerobiose sobre a gera o de espécies reativas de oxigênio (ERO). Verificou-se que o dano celular e tecidual por radicais livres, causado por peroxida o lipídica e inflama o, ocorre em ambos os tipos de exercícios físicos, sobretudo em esfor os de alta intensidade. Existem indica es de que a gera o de ERO durante o exercício físico n o pode ser modulada pelo treinamento regular, contudo, o ambiente celular pode aumentar a concentra o endógena de antioxidantes para compensar o estresse provocado. Além disso, a regula o de ERO pode acontecer de forma diferenciada em exercícios aeróbios e anaeróbios. Portanto, o monitoramento do estresse oxidativo pode ser bastante importante, particularmente, em exercícios anaeróbios.
Mutagenic activation of CL64,855, an anti-Trypanosoma cruzi nitroderivant, by bacterial nitroreductases
Morais Jr., Marcos Antonio de;Ferreira, Rita de Cássia Café;Ferreira, Luiz Carlos de Souza;
Genetics and Molecular Biology , 1998, DOI: 10.1590/S1415-47571998000400026
Abstract: cl64,855 is a nitroimidazole-thiodiazole derivate with high anti-trypanosoma cruzi activity. cl64,855-induced mutagenesis in the salmonella/microsome test was detected by ta98 and ta98dnp6 strains, but not by the nitroreductase i-deficient ta98nr strain. the lack of mutagenic response of ta98nr was connected with its extreme resistance to the killing effect of the drug. presence of s9 mix did not restore mutagenic activity of cl64,855 to the ta98nr strain. additionally, cl64,855 was reduced in vitro by the nitroreductase i-proficient ta98 strain, mainly in the presence of oxygen, but not by the ta98nr strain. mutagenic activity was detected in serum samples of treated guinea pigs by nitroreductase-proficient strains ta98 and ta98dnp6, but not by nitroductase-deficient strain ta98nr. in the case of urine, mutagenic activity was observed with all three tested strains, suggesting an in vivo metabolic activation of the drug by a distinct metabolic pathway.
Mutagenic activation of CL64,855, an anti-Trypanosoma cruzi nitroderivant, by bacterial nitroreductases
Morais Jr. Marcos Antonio de,Ferreira Rita de Cássia Café,Ferreira Luiz Carlos de Souza
Genetics and Molecular Biology , 1998,
Abstract: CL64,855 is a nitroimidazole-thiodiazole derivate with high anti-Trypanosoma cruzi activity. CL64,855-induced mutagenesis in the Salmonella/microsome test was detected by TA98 and TA98dnp6 strains, but not by the nitroreductase I-deficient TA98nr strain. The lack of mutagenic response of TA98nr was connected with its extreme resistance to the killing effect of the drug. Presence of S9 mix did not restore mutagenic activity of CL64,855 to the TA98nr strain. Additionally, CL64,855 was reduced in vitro by the nitroreductase I-proficient TA98 strain, mainly in the presence of oxygen, but not by the TA98nr strain. Mutagenic activity was detected in serum samples of treated guinea pigs by nitroreductase-proficient strains TA98 and TA98dnp6, but not by nitroductase-deficient strain TA98nr. In the case of urine, mutagenic activity was observed with all three tested strains, suggesting an in vivo metabolic activation of the drug by a distinct metabolic pathway.
Teor de proteína e de óleo nos gr?os de soja em fun??o do tratamento de sementes e aplica??o de micronutrientes
Souza, Luiz Carlos Ferreira de;Zanon, Graciela Decian;Pedroso, Fernanda Ferreira;Andrade, Lucio Henrique Leite de;
Ciência e Agrotecnologia , 2009, DOI: 10.1590/S1413-70542009000600018
Abstract: the objective of this work was to verify the effect of the use of inoculant, fungicide, and micronutrients on yield, and on the chemical composition of soybean grains. in the 2005/2006 crop, a study with different seed treatments and leaf applications of micronutrients was done. agronomic characteristics and yield were evaluated, as well as, oil, protein, and nutritional contents of soybean leaves and grains. plant height was influenced significantly by the applied treatments, with the smallest average of plant height being observed in control ( 89.75 cm). stem diameter, number of beans per plant, and bio mass of 100 seeds were not influenced by treatments. under the conditions in which the experiments were carried out, in soil with good fertility, the adopted treatments did not significantly influence yield, nor protein and oil content of grains, nor chemical composition of soybean leaves and grains.
Comparative Skill of Numerical Weather Forecasts in Eastern Amazonia  [PDF]
Bergson Cavalcanti de Moraes, Douglas Batista da Silva Ferreira, Luiz Gylvan Meira Filho, Juarez Ventura de Oliveira, Everaldo Barreiros de Souza, Pedro Pereira Ferreira Júnior, Renata Kelen Cardoso Camara, Edson José P. da Rocha, Jo?o Batista M. Ribeiro
Atmospheric and Climate Sciences (ACS) , 2013, DOI: 10.4236/acs.2013.33037

The present study evaluates the performance of three numerical weather forecasting models: Global Forecast System (GFS), Brazilian Regional Atmospheric Modelling System (BRAMS) and ETA Regional Model (ETA), by means of the Mean Error (ME) and the Root Mean Square Error (RMSE), during the most rainy four months period (January to April 2012) on Eastern Amazonia. The models displayed errors of superestimation and underestimation with respect to the observed precipitation, mainly over center-north of Pará and all of Amapá, where the precipitation is higher. Among the analyzed models, GFS shows the best performance, except during January and March, when the model to underestimated precipitation, possibly due to the anomalously high values recorded.

Prevalence of dyslipidemia and risk factors in Campos dos Goytacazes, in the Brazilian State of Rio de Janeiro
Souza Luiz José de,Souto Filho Jo?o Tadeu Damian,Souza Thiago Ferreira de,Reis Aldo Franklin Ferreira
Arquivos Brasileiros de Cardiologia , 2003,
Abstract: OBJECTIVE: To determine the prevalence of dyslipidemias in adults in the city of Campos dos Goytacazes, in the Brazilian state of Rio de Janeiro, and to identify its relation to risk factors. METHODS: Cross-sectional, population-based, observational study with sampling through conglomerates and stratified according to socioeconomic levels, sex, and age, with 1,039 individuals. Risk factors, familial history, blood pressure, anthropometric measurements, glucose, triglycerides and cholesterol were determined. RESULTS: The following prevalences were observed: of dyslipidemias 24.2%; of hypercholesterolemia, 4.2%; of elevated LDL-C, 3.5%; of low HDL-C, 18.3%; and of hypertriglyceridemia, 17.1%. The following mean levels were observed: cholesterol, 187.6± 33.7 mg/dL; LDL-C, 108.7±26.8 mg/dL; HDL-C, 48.5±7.7 mg/dL; and triglycerides, 150.1±109.8 mg/dL. The following variables showed a positive correlation with dyslipidemia: increased age (P<0.001), male sex (P<0.001), low familial income (P<0.001), familial history (P<0.01), overweight/obesity (P<0.001), waist measure (P<0.001), high blood pressure (P<0.001), and diabetes mellitus (P<0.001). The following variables had no influence on dyslipidemias: ethnicity, educational level, smoking habits, and sedentary lifestyle. CONCLUSION: The frequency of lipid changes in the population studied was high, suggesting that measures for the early diagnosis should be taken, in association with implementation of programs for primary and secondary prevention of atherosclerosis.
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