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Search Results: 1 - 10 of 327475 matches for " Francinaldo S. Braga "
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Application of Hartree-Fock Method for Modeling of Bioactive Molecules Using SAR and QSPR  [PDF]
Cleydson B. R. Santos, Cleison C. Lobato, Francinaldo S. Braga, Sílvia S. S. Morais, Cesar F. Santos, Caio P. Fernandes, Davi S. B. Brasil, Lorane I. S. Hage-Melim, Williams J. C. Macêdo, José C. T. Carvalho
Computational Molecular Bioscience (CMB) , 2014, DOI: 10.4236/cmb.2014.41001
The central importance of quantum chemistry is to obtain solutions of the Schr?dinger equation for the accurate determination of the properties of atomic and molecular systems that occurred from the calculation of wave functions accurate for many diatomic and polyatomic molecules, using Self Consistent Field method (SCF). The application of quantum chemical methods in the study and planning of bioactive compounds has become a common practice nowadays. From the point of view of planning it is important to note, when it comes to the use of molecular modeling, a collective term that refers to methods and theoretical modeling and computational techniques to mimic the behavior of molecules, not intend to reach a bioactive molecule simply through the use of computer programs. The choice of method for energy minimization depends on factors related to the size of the molecule, parameters of availability, stored data and computational resources. Molecular models generated by the computer are the result of mathematical equations that estimate the positions and properties of the electrons and nuclei, the calculations exploit experimentally, the characteristics of a structure, providing a new perspective on the molecule. In this work we show that studies of Highest Occupied Molecular Orbital Energy (HOMO), Low Unoccupied Molecular Orbital Energy (LUMO) and Map of molecular electrostatic potential (MEP) using Hatree-Fock method with different basis sets (HF/3-21G*, HF/3-21G**, HF/6-31G, HF/6-31G*, HF/6-31G** and HF/6-311G), that are of great importance in modern chemistry, biochemistry, molecular biology, and other fields of knowledge of health sciences. In order to obtain a significant correlation, it is essential that the descriptors are used appropriately. Thus, the quantum chemical calculations are an attractive source of new molecular descriptors that can, in principle, express all the geometrical and electronic properties of molecules and their interactions with biological receptor.
Computational Analysis of Physicochemical, Pharmacokinetic and Toxicological Properties of Deoxyhypusine Synthase Inhibitors with Antimalarial Activity  [PDF]
Nayara S. R. Silva, Luana K. S. Gon?alves, Jonatas L. Duarte, Juliane S. Silva, César F. Santos, Francinaldo S. Braga, Raí C. Silva, Josivan S. Costa, Lorane I. S. Hage-Melim, Cleydson B. R. dos Santos
Computational Molecular Bioscience (CMB) , 2014, DOI: 10.4236/cmb.2014.44006
Abstract: Malaria is a parasitic disease which has as etiological agents protozoa of the genus Plasmodium prevalent in tropical countries. The appearance of Plasmodium strains resistant to artemisinin has become necessary the development of new drugs using computational tools to combat this epidemic. Diverse transporter proteins can act as antimalarials targets, thereby being the enzyme deoxyhypusine synthase a promising antimalarial target. The present study aimed to investigate 15 most active inhibitors of deoxyhypusine synthase target, deposited in databases Binding DB, in order to trace a pattern of physicochemical, pharmacokinetic and toxicological properties of the inhibitors for this enzyme and propose new inhibitors of deoxyhypusine synthase target. The physicochemical properties were obtained according to the Lipinski parameters to evaluate oral absorption. Based on the certain properties were proposed three new inhibitors (A, B and C). The ADME/Tox properties were calculated for new inhibitors compared with results of the selected compounds. The fifteen inhibitors for oral administration showed satisfactory results, because they have adapted to the Lipinski parameters. In relation to the penetration of the blood-brain barrier the inhibitors analyzed showed penetration values less than 1, and ranged from 0.0411815 to 0.481764, being that the compound 1 showed value of CBrain/CBlood = 0.135467. Compound B showed a higher strength in plasma protein binding in relation to the compound 1, having a variation be-tween them of ±1.489344. Therefore, the compound B would present a longer halflife compared with compound 1. The proposed compounds showed positive and satisfactory results, being able to reach less adverse effects related to the central nervous system depending of administered dose.
Orchid bee (Hymenoptera: Apidae) community from a gallery forest in the Brazilian Cerrado
Francinaldo S Silva
Revista de Biología Tropical , 2012,
Abstract: The orchid bees are a very important group of pollinators distributed in the Neotropics. Although a lot of studies concerning male euglossine bees have been done in this region, few works have so far been carried out in the Cerrado biome. This manuscript has the main objective to present the orchid bee community from a Gallery Forest in the Northeastern Brazilian Cerrado landscape, taking account the species composition, abundance, seasonality and hourly distribution. Male euglossine bees were collected monthly from October 2007 to May 2009, in the Reserva Florestal da Itamacaoca belonging to the Companhia de água e Esgoto do Maranh o, in Chapadinha municipality, Maranh o State. The scents eucalyptol, eugenol and vanillin were utilized, between 07:00 and 17:00hr, to attract the euglossine males. Cotton balls were dampened with the scents and suspended by a string on tree branches 1.5m above soil level, set 8m from one another. The specimens were captured with entomological nets, killed with ethyl acetate and transported to the laboratory to be identified. A total of 158 individuals and 14 species of bees were recorded. The genus Eulaema was the most representative group of euglossine bees in relation to the total number of the sampled individuals, accounting for 50.6% of bees followed by Euglossa (26.6%), Eufriesea (15.2%) and Exaerete (7.6%). The most frequent species were Eulaema nigrita (27.8%), Eulaema cingulata (19%) and Euglossa cordata (18.3%). Many species typical of forested environments were found in samples, like Euglossa avicula, Euglossa violaceifrons and Eulaema meriana, emphasizing the role played by the Gallery Forests as bridge sites to connect the two great biomes of Amazonia and Atlantic Forest. The occurrence of Exaerete guaykuru represents the second record of this species for the Neotropical region, and both records coming from the Gallery Forest zones. The male euglossine bees were sampled mainly in the dry season, where 62.5% of the individuals were collected in that period. Eufriesea species appeared at the baits only in the wet season. The hourly frequency of bees at scent baits showed a clear preference for the morning period, where 87.9% visited the baits from 07:00 to 12:00hr. The euglossine bee fauna found in the Northeastern Maranh o Cerrado is represented chiefly by species of large geographic distribution and by some forest bee species, where their occurrence is maybe related to to the environmental conditions supported by the Gallery Forest ecosystem. Rev. Biol. Trop. 60 (2): 625-633. Epub 2012 June 01. Las abejas de las
Distribui??o das abelhas Euglossini (Hymenoptera: Apidae) no estado do Maranh?o, Brasil
Rebêlo, José Manuel M.;Silva, Francinaldo S.;
Anais da Sociedade Entomológica do Brasil , 1999, DOI: 10.1590/S0301-80591999000300003
Abstract: this work presents a check-list and comment on the distribution of the species of euglossini found in the state of maranh?o, based on works conducted in several areas with odoriferous baits. the sampling of the bees followed a standardized methodology during one year, once a month, in the municipalities of barreirinhas, buriticupu, s?o luís and vitória do mearim, with captures from six and 12 hours. in the other localities were made aleatory collects. the chemical baits used in the attraction of males were cineole, eugenol, vanillin, methyl salicylate and benzyl benzoate. a total of 44 species were found belonging to the following genera: euglossa (25 species), eufriesea (11), eulaema (5) and exaerete (3). about 81,8% are present in the amazonian areas and 65,9% in the areas with more open vegetation with influence of the "cerrados" and "baba?uais" which occupy great part of the state.
Central neurocytomas of uncommon locations: report of two cases
Gomes, Francinaldo Lobato;Fran?a, Luciano Ricardo;Zymberg, Samuel Tau;Cavalheiro, Sérgio;
Arquivos de Neuro-Psiquiatria , 2006, DOI: 10.1590/S0004-282X2006000600025
Abstract: we report two patients with central neurocytomas at an uncommon location in the brain. the first, a 58-year-old man presenting with signs and symptoms of increased intracranial pressure, had a tumor located at the pineal region. the second, a 21-year-old woman with tumor in the aqueductal region had worsening migraine-like headaches and diplopia. both patients had obstructive hydrocephalus treated by neuroendoscopic third ventriculostomy and biopsy of the tumors. no additional treatment was done. we conclude that neurocytomas should be considered in the differential diagnosis of tumors located in the pineal and aqueductal regions.
Sand flies (Diptera: Psychodidae) in a cerrado area of the Maranh?o state, Brazil
Silva, Francinaldo S;Carvalho, Luis P C de;Cardozo, Francisco P;Moraes, Jorge L P;Rebêlo, José M M;
Neotropical Entomology , 2010, DOI: 10.1590/S1519-566X2010000600028
Abstract: the present paper aims to increase the knowledge on the sand fly fauna in the cerrado areas of maranh?o state in urban, rural and forest environments. the research was carried out from october 2007 to september 2008, between 18:00h and 06:00h, in the municipality of chapadinha, northeast maranh?o. for insect sampling, cdc light traps were set up in peridomicile and domicile areas of urban and rural zones as well as in cerrado and gallery forests. the total of 1,401 specimens belonging to 17 species were sampled, all within the genus lutzomyia. lutzomyia longipalpis (lutz & neiva) (52.5%), lu. evandroi (costa lima & antunes) (18.3%), lu. whitmani (antunes & coutinho) (12.1%), lu. lenti (mangabeira) (4.7%) and lu. termitophila (martins, falc?o & silva) (4.0%) were the most frequently collected. from an epidemiological viewpoint, five from all of the collected species are vectors of leishmaniasis: lu. longipalpis, lu. whitmani, lu. flaviscutellata (mangabeira), lu. gomezi (nitzulescu) and lu. chagasi (costa lima). lutzomyia chagasi was registered for the first time in maranh?o state and lu. saulensis (floch & abonnenc), lu. monstruosa (floch & abonnenc) and lu. gomezi were found for the first time in the eastern part of the state, since they had been reported only in the amazonian region of maranh?o. regarding to the studied environments, the urban chicken house had the highest number of specimens collected (801), while the gallery forest was the most diverse (15 species). this study demonstrates that the northeast cerrado exhibits a mixed sand fly fauna characterized by an extremely important species vectors assortment involved in the epidemiological cycle of leishmaniasis in maranh?o state.
Métodos de compila??o e computa??o de dados estatísticos de desembarque de pescado no p?rto de Santos
Braga, A. S.;
Boletim do Instituto Oceanográfico , 1962, DOI: 10.1590/S0373-55241962000200002
Abstract: the development of programs of research on marine fisheries begun in 1958 by the santos group have drawn attention to the necessity of improvement of methods of collecting fishery statistics; although the collections were originally started in 1950, the early years' work were not a high standard, partially due to the high cost of personnel and means. now, the research is becoming more exacting in its statistical requirements. it may be seen, from the analysis of data presented in this paper, that the s?o paulo fishery has been evolving slowly, depending mostly on its own resources. beginning in 1958, there was a "revolution", the result of adding to the fleet larger vessels, both brazilian and foreign, which have raised the fishing activities to a level never before achieved. the general tendencies are for fishing in more distant and more productive waters both to the north with long-lines and along the coast to the south with trawls, and the effects of these tendencies have been increases in both the volume and quality of the fishery products landed.
Podem as novas tecnologias de informa??o e comunica??o auxiliar na consolida??o das democracias? Um estudo sobre a informatiza??o dos órg?os legislativos na América do Sul
Braga, Sérgio Soares;
Opini?o Pública , 2007, DOI: 10.1590/S0104-62762007000100001
Abstract: the objective of this article is to present the results of our research about the informatization of the legislative bodies in the south america. this general objective is divided in two specific objectives: a) to present a proposal of mensurement of the degree of informatization of these parliamentary agencies, evaluating how much the parliaments of these countries had advanced in this process; b) to elaborate and to apply metodological instruments for the analysis of data, as well as for the evaluation of the analytical meaning of that informations, and on its impact in the functioning of the democratic institutions of latin america in general, and the south america in particular, especially in the control of the representatives for the citizens.
Poder, formas de domina??o e Estado no diálogo entre Nicos Poulantzas e a sociologia política norte-americana
Braga, Sérgio;
Revista Brasileira de Ciência Política , 2011, DOI: 10.1590/S0103-33522011000100005
Abstract: the article aims at recovering the terms of the critical dialogue about more general concepts of political theory (such as power, domination, state) sustained by nicos poulantzas with some representatives of the "american political sociology". our basic hypothesis is that the originality of some of poulantzas' contributions in his early works is strongly related, among other things, to the dialogue with such authors who formed the mainstream of the academic political science at the time. as an additional proposition, we argue for the need of resuming that critical dialogue and of systematically incorporating into the theoretical universe of the structural-marxist political sociology some of the major categories developed by pluralist and systemic political scientists (such as those of power, influence, authority, political system and political elites). in this sense, we argue against the arguments put forward by some analysts about the existence of a radical incompatibility or a "zero-sum" relationship between notions employed by political scientists of these two theoretical traditions.
Uso do campo potencial na explora??o dos recursos minerais marinhos
Dias, Marcelo S.;Braga, Luiz F. S.;
Revista Brasileira de Geofísica , 2000, DOI: 10.1590/S0102-261X2000000300005
Abstract: the potential field methods have been widely used for exploration geophysics since the beginning of the last century. in general, their applications were for preliminary regional mapping of large geological structures related to mineral resources such as: basin boundary faults, grabens and horsts, salt diapirs, basement geometry and heat flow estimates. however, during the last decade, a new branch of equipment (satellite altimeter, gravity and magnetic gradiometers, cesium magnetometers, dgps and powerful computers) made available an enormous volume of high-resolution data for marine mineral resources exploration. nowadays, these data are being used for calibrating small density and magnetic susceptibility contrasts that are fundamental for investigating a number of exploration issues: i) velocity correction for 3d and 4d seismic reflection; ii) micro-gravity and micro-magnetic for core geophysics, iii) high resolution density and porosity for pore fluids; iv) potential hazards structures and v) sulfides and polimetallic nodules in oceanic crust. a new vision of these applications is already in use by the mineral exploration industry. the main goal of this paper is to make a brief review and also give some background on those applications.
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