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Search Results: 1 - 10 of 31729 matches for " Ronaldo do;Ferreira "
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Initial Growth and Gas Exchanges of Plants of Colored Cotton Submitted to Saline Stress  [PDF]
Hallyson Oliveira, Ronaldo do Nascimento, Samuel Silva, José Alberto Ferreira Cardoso, Rafaela Felix Basílio Guimar?es, Elka Costa Santos Nascimento
Agricultural Sciences (AS) , 2018, DOI: 10.4236/as.2018.912115
Abstract: The objective of the research was to evaluate the effects of saline stress on the initial growth and physiological parameters of three varieties of cotton plants, being two cultivars of colored fiber (BRS Topázio and BRS Verde) and one of white fiber (BRS 286). The experiment was conducted under greenhouse conditions. After chemical depletion with sulfuric acid, five seeds were seeded in polyethylene pots of 20 kg, leaving only one plant per pot after thinning. The experimental design was completely randomized, with a factorial scheme of 3 × 5, with five replications, totaling 75 plots, being three cotton varieties and five saline stress treatments—1.1; 3.1; 5.1; 7.1; 9.1 dS m1. The evaluations occurred at 15 and 30 days after the beginning of the treatments (DAT) for growth variables (plant height, stem diameter, number of leaves and leaf area) and gas exchange (stomatal conductance, net photosynthesis rate and transpiration. The variety that was most resistant to the salt stress levels studied was BRS 286, followed by BRS Topazio and BRS Verde.
Aduba??o foliar e via solo de nitrogênio em plantas de milho em fase inicial de desenvolvimento
Deuner, Sidnei;Nascimento, Ronaldo do;Ferreira, Ladislau Soares;Badinelli, Pablo Gerson;Kerber, Romel Silva;
Ciência e Agrotecnologia , 2008, DOI: 10.1590/S1413-70542008000500001
Abstract: consider the most important nutrient in the increment of grain gield and also the proteic level, nitrogen (n), in addition of this fact, this nutrient is the component that most increases the production cost of maize crop. this study aimed to verify whether the application of leaf nitrogen influences the accumulation of proteins and parameters of growth of young plants of maize compared to the application of urea via soil. for both, young plants of the hybrid maize br 206 received applications of urea as a source of n via leaf and soil at concentrations of zero, 0.5% and 1.0%. the plants were grown in a greenhouse being held three applications of n, the first for six days after the emergency (dae) in a volume of 10 ml per plant and the following two to 10 and 14 dae with 20 ml each. at 18 dae the plants were collected and analyses proceeded. for plant height, root volum, leaf area, dry weigth of leaf area and root, one verified a higher efficiency of leaf fertilization, mainly at 0,5% level of urea. the application of urea 1,0% via soil caused a significative increase in leaf protein levels. these results suggest that leaf fertilization may be an efficient mode to complement what is uptaken by the roots, although it should not be used as a unique source of inorganic n to the plants.
Luciana Borges e Silva,Jorge Luiz do Nascimento,Ronaldo Veloso Naves,Paulo Henrique Ferreira
Pesquisa Agropecuária Tropical , 2007, DOI: 10.5216/pat.v34i2.2331
Abstract: O objetivo deste estudo foi avaliar o comportamento vegetativo de cultivares de banana sob diferentes laminas de irriga o, nas condi es de cerrado goiano. As laminas de irriga o corresponderam a 30, 65, 100 e 135% da evapotranspira o potencial da cultura (ETpc) estimada a partir da evapora o do tanque Classe A. O experimento foi conduzido na área experimental da Escola de Agronomia e Engenharia de Alimentos, da Universidade Federal de Goiás, em Goiania-GO, no período de 24 de maio 2001 a 15 de outubro de 2002. A cultivar FHIA 18, diferentemente das demais, mostrou resposta significativa às laminas de irriga o, para as variáveis avaliadas. A irriga o influenciou no diametro dos pseudocaules, no diametro dos pseudocaules na inser o do cacho, no número de folhas vivas e nos ciclos produtivo e total das plantas. As cultivares Grande Naine (grupo gen mico AAA) e Prata comum (AAB), diferentemente da cultivar FHIA 18 (AAAB), n o foram influenciadas pelas laminas de irriga o. PALAVRAS-CHAVE: Musa sp.; irriga o; evapotranspira o. The objective of this study was to evaluate the vegetative behavior of three banana cultivars to different levels of irrigation, in the Goiás cerrado. The irrigation levels corresponded to 30, 65, 100 and 135% of the potential evapotranspiration of the crop (ETpc) based on evaporation in a classe-A tank. A field experiment was carried out in the experimental area of the “Escola de Agronomia e Engenharia de Alimentos, Universidade Federal de Goiás”, Goiania-GO, from May 24, 2001 to October 15, 2002. Cultivar FHIA 18, unlike of the others, showed a significant response to variation in irrigation levels for the observed variables. The irrigation affected the diameter of the pseudostems, the diameter of the pseudostems at point of insertion of the bunch, the number of live leaves and the productive and total cycles of the plants. Grande Naine and Prata cultivars, unlike of the FHIA 18, were not affected by irrigation levels. KEY-WORDS: Musa sp.; irrigation; evapotranspiration.
Avalia??o do potencial de contamina??o de águas superficiais e subterraneas por pesticidas aplicados na agricultura do Baixo Jaguaribe, CE
Milhome, Maria Aparecida Liberato;Sousa, Daniele de Oliveira Bezerra de;Lima, Francisco de Assis Ferreira;Nascimento, Ronaldo Ferreira do;
Engenharia Sanitaria e Ambiental , 2009, DOI: 10.1590/S1413-41522009000300010
Abstract: this study evaluated the potential of contamination of surface water and groundwater in the irrigated agriculture of baixo jaguaribe, in ceara state, brazil. the analysis was performed based on the criteria of the environmental protection agency (epa), the index of gus and method of goss. these indexes have been based on physical and chemical properties of the active ingredients of each pesticide. the present paper assessed the main products, which are applied on crops in the irrigated agriculture of baixo jaguaribe, through survey in the region. the comparison between the models showed some potential for pesticide contamination in surface water and groundwater, and requires the constant monitoring of levels waste.
Neutral Sterols of Cephalic Glands of Stingless Bees and Their Correlation with Sterols from Pollen
Maria Juliana Ferreira-Caliman,Cláudia Inês da Silva,Sidnei Mateus,Ronaldo Zucchi,Fabio Santos do Nascimento
Psyche , 2012, DOI: 10.1155/2012/982802
Abstract: Sterols are essential molecules in the membrane lipid composition and precursors of important sterol hormones that regulate many developmental processes. Insects are unable to synthesize sterols de novo and, thus, all phytophagous insects depend on an exogenous source of sterols for growth, development, and reproduction. The sterol requirements of social bees are not fully known due to the fact that there is no well-defined diet available throughout the year with regard to floral resources. Our study aimed to characterize the sterols present in pollen stored in Melipona marginata and Melipona scutellaris colonies, as well as evaluating their presence in the mandibular, hypopharyngeal, and cephalic salivary gland secretions. We analyzed the chemical composition of pollen stored in the colonies and the composition of the cephalic glands of workers in three adult functional phases (newly emerged, nurses, and foragers) by gas chromatography and mass spectrometry. The results showed that the pollen analyzed contained campesterol, stigmasterol, sitosterol, isofucosterol, lanosterol, and small amounts of cholesterol. The glands showed the same compounds found in the pollen analyzed, except lanosterol that was not found in M. scutellaris glands. Surprisingly, cholesterol was found in some glands with relative ratios greater than those found in pollen. 1. Introduction Sterols are essential molecules in cell membrane, they are precursors of sterol hormones and other important regulators of developmental processes. However, insects are unable to synthesize them and have to purchase sterols from their diet [1]. The dietary needs for sterols in insects were firstly reported by Hobson [2] in the blowfly Lucilia sericata. Moreover, in 1959, Clark and Bloch [3] showed the inability of insects to synthesize sterols de novo, so that they need to purchase these compounds for auxotrophy (from the Greek “to increase” and “nutrition”). Auxotrophic individuals are unable to synthesize organic compounds necessary for its growth. These authors showed the importance of sterols as structural (cholestanol) and metabolic (cholesterol) components in insects. Further studies showed that ecdysteroids derivatives from cholesterol participate in the control of insect growth and maturation [4]. Furthermore, the necessity of sterol ingestion by insects has been demonstrated in different orders including Orthoptera, Hemiptera, Diptera, Lepidoptera, and Hymenoptera [5]. Indeed, all phytophagous insects studied to date rely on exogenous sterol for growth, reproduction and development [6, 7].
Avalia??o do tratamento térmico na composi??o química e na qualidade da cajuína
Nascimento, Ronaldo Ferreira do;Aquino, Francisco Wendel Batista de;Amorim, Adriany G. Nascimento;Prata, Laércio Favila;
Ciência e Tecnologia de Alimentos , 2003, DOI: 10.1590/S0101-20612003000200020
Abstract: in this work the effect of the thermal process on the quality and chemical composition of the beverage cajuína was studied. cajuína is basically clarified cashew juice. samples of cajuína were submitted to thermal processes, of constant heating (100oc) for 1:00, 1:30, 2:00, 2:30, 3:00 and 4:00 hours. the samples were subsequently analyzed by hplc for glucose, fructose, citric acid, ascorbic acid, hydroxymethylfurfural (5-hmf) and furfural. the results showed that the commercial cajuína beverage of ceará state presented a great diversity in process standardization and vitamin c content, caused by inadequate thermal processing. the process is more efficient with a time period of 2:00hs. the work also indicates a combination of the analyses of 5-hmf, furfural and ascorbic acid and the ratio ascorbic acid/citric acid, as an alternative methodology for the evaluation of cajuína quality.
Determina??o de aditivos, aldeídos furanicos, a?úcares e cafeína em bebidas por cromatografia líquida de alta eficiência: valida??o de metodologias
Aquino, Francisco Wendel Batista de;Amorim, Adriany G. Nascimento;Prata, Laércio Favilla;Nascimento, Ronaldo Ferreira do;
Ciência e Tecnologia de Alimentos , 2004, DOI: 10.1590/S0101-20612004000100007
Abstract: in this work methodologies chromatographic have been evaluated and validated for the determination of caffeine, furfural, 5-hmf, saccharin, sodium benzoate glucose, fructose, acid citric and acid ascorbic in different food products of ceara state, brazil. the study has been evidenced that 66% of the cajuinas, present low quality because of the process of heating, and 12% of the soft drinks presented content of sodium benzoate above the limit tolerated by brazilian legislation and 29% of the soft drinks illegal saccharin addition. the methodologies were validated in function of the precision, experimental recovery, linearity of the analytical curves, limit of detection and quantification for each compound studied. the precision (r.s.d%) of the determination of each compound varied of 2.85 to 8.35 % and recovery was between 95,1 to 105,5 %. the linearity of the analytical curves were satisfactory with coefficients of correlation greater than 0.990. the limit of detection and quantification of each compound were obtained in level of μg/l.
Local distribution of blackfly (Diptera, Simuliidae) larvae in two adjacent streams: the role of water current velocity in the diversity of blackfly larvae
Figueiró, Ronaldo;Nascimento, érika Silva do;Gil-Azevedo, Leonardo Henrique;Maia-Herzog, Marilza;Monteiro, Ricardo Ferreira;
Revista Brasileira de Entomologia , 2008, DOI: 10.1590/S0085-56262008000300020
Abstract: this study aimed to evaluate the influence of water velocity speed on the local distribution and taxocenosis structure of blackfly larvae. the larvae were collected from two adjacent streams located in the municipality of angra dos reis (rj): caputera river and one of its tributaries. riffle litter patches were sampled randomly using a 30 x 30 cm quadrat. four blackfly species were found: simulium incrustatum s. l. lutz, 1910; simulium (inaequalium) sp. ; simulium pertinax s. l. kollar, 1832 and simulium subpallidum s. l. lutz, 1909. among these species, simulium pertinax s. l. was clearly associated with higher water current speeds, while simulium subpallidum s. l. showed association with lower water velocities, and simulium (inaequalium) sp. had a relatively constant distribution along the water current gradient.
Caracteriza??o de frutos e árvores de popula??es naturais de Hancornia speciosa Gomes do cerrado
Ganga, Rita Maria Devós;Ferreira, Gislene Auxiliadora;Chaves, Lázaro José;Naves, Ronaldo Veloso;Nascimento, Jorge Luiz do;
Revista Brasileira de Fruticultura , 2010, DOI: 10.1590/S0100-29452010005000019
Abstract: the research intends to characterize trees and fruits from natural populations of hancornia speciosa gomes, as well as evaluate the distribution of phenotypic variability among them. populations of mangaba trees were sampled in the cerrado, including the states of goiás, tocantins, mato grosso, mato grosso do sul, and bahia, covering 109 mother plants from 35 populations of the botanical varieties pubescens, gardneri, speciosa and cuyabensis. the results showed that the h. speciosa plants have high levels of phenotypic variation in terms of fruit characterization and, on the whole, most of this variation occurs among populations. there is also a large phenotypic variability within the botanical varieties. h. speciosa var. gardneri and h. speciosa var. pubescens fruits are larger and heavier. the botanic variety gardneri shows gait more high than the others varieties. in the varieties gardneri and pubescens predominate round shape and light green color, while in speciosa and cuyabensis predominate oblong shape and dark yellow and dark green colors, respectively. the varieties gardneri and pubescens stand out as the most potential for selection based on the characters of the fruit size and fruit mass.
Avalia o do tratamento térmico na composi o química e na qualidade da cajuína
Nascimento Ronaldo Ferreira do,Aquino Francisco Wendel Batista de,Amorim Adriany G. Nascimento,Prata Laércio Favila
Ciência e Tecnologia de Alimentos , 2003,
Abstract: Neste trabalho foi estudado o efeito do processo de tratamento térmico na qualidade e composi o química da bebida cajuína quando submetida ao cozimento sob temperatura constante de 100oC durante 1:00, 1:30, 2:00, 2:30, 3:00 e 4:00 horas. Alíquotas foram coletadas em cada tempo de aquecimento e analisadas por cromatografia líquida de alta eficiência (CLAE) em rela o aos ácidos (cítrico e ascórbico), aldeídos furanicos (5-hidroximetilfurfural e furfural) e a úcares (frutose, glicose e frutose). Os resultados foram reprodutíveis e indicaram que as cajuínas comerciais do estado do Ceará apresentam uma grande diversidade quanto ao processo de cozimento e ao teor de vitamina C, causados principalmente por processos térmicos inadequados. O tempo mais adequado sugerido para o "cozimento" da cajuína está em torno de 2:00h. O trabalho também aponta a combina o das análises de 5-HMF, furfural, ácido ascórbico e teor de ácido ascórbico/ácido cítrico como uma metodologia alternativa para a avalia o da qualidade da cajuína.
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