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Search Results: 1 - 10 of 19187 matches for " Davi do Socorro Barros Brasil "
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Surface Modification of Commercial Activated Carbon (CAG) for the Adsorption of Benzene and Toluene  [PDF]
Anna Sylmara da Costa Lopes, Samira Maria Le?o de Carvalho, Davi do Socorro Barros Brasil, Rosivaldo de Alcantara Mendes, Marcelo Oliveira Lima
American Journal of Analytical Chemistry (AJAC) , 2015, DOI: 10.4236/ajac.2015.66051
Abstract: In this work, we determined the surface characteristics of natural (CA-1) and HNO3 treated (CA-2) CAG. Equilibrium, kinetics and breakthrough for adsorption of benzene and toluene by CA-1 and CA-2 were studied. Concentrations of benzene and toluene (mg/L) were determined by gas chromatography with headspace extraction. The data of adsorption kinetic and equilibrium were best fitted by pseudo-second order model and Langmuir isotherm, respectively. The best results of benzene and toluene adsorption from fixed bed were obtained at volumetric flow rate (Q1 = 70 mL/min) using adsorbent CA-2. The study of inferential statistics revealed that CA-1 and CA-2 adsorbents are statistically different at a 5% significance level.
Essential oil composition of Croton palanostigma Klotzsch from north Brazil
Brasil, Davi do Socorro B.;Muller, Adolfo Henrique;Guilhon, Giselle Maria S. P.;Alves, Cláudio Nahum;Andrade, Eloísa Helena A.;Silva, Joyce Kelly R. da;Maia, José G. S.;
Journal of the Brazilian Chemical Society , 2009, DOI: 10.1590/S0103-50532009000600026
Abstract: the essential oils of leaves, twigs, branches, trunk bark and fruits of croton palanostigma were analyzed by gc and gc-ms. the main compounds found in the oil of the leaves were linalool (25.4%), (e)-caryophyllene (21.0%), methyleugenol (17.2%) and β-elemene (6.0%); in the oil of the twigs were α-pinene (41.4%), limonene (29.0%), sabinene (11.5%) and β-pinene (5.7%); in the oil of the branches were methyleugenol (24.1%), (e)-methylisoeugenol (15.3%), α-pinene (11.2%) and (e)-caryophyllene (8.5%); in the oil of the trunk bark were a-pinene (31.6%), methyleugenol (25.6%) and (e)-methylisoeugenol (23.7%); and in the oil of the fruits were linalool (42.7%), methyleugenol (16.3%) and β-elemene (6.4%). statistical analysis showed that the leaves and fruit, and the branches and trunk bark, have significant similarities between them. in addition, the trunk bark oil has high brine shrimp larvicidal activity (lc50, 3.71 ± 0.01 mg ml-1).
Evaluation of Quantum Chemical Methods and Basis Sets Applied in the Molecular Modeling of Artemisinin  [PDF]
Cleydson B. R. dos Santos, Cleison C. Lobato, Josinete B. Vieira, Davi S. B. Brasil, Alaan U. Brito, Williams J. C. Macêdo, José Carlos T. Carvalho, José C. Pinheiro
Computational Molecular Bioscience (CMB) , 2013, DOI: 10.4236/cmb.2013.33009
Abstract: In this paper, we evaluate semiempirical methods (AM1, PM3, and ZINDO), HF and DFT (B3LYP) in different basis sets to determine which method best describes the sign and magnitude of the geometrical parameters of artemisinin in the region of the endoperoxide ring compared to crystallographic data. We also classify these methods using statistical analysis. The results of PCA were based on three main components, explaining 98.0539% of the total variance, for the geometrical parameters C3O13, O1O2C3, O13C12C12a, and O2C3O13C12. The DFT method (B3LYP) corresponded well with the experimental data in the hierarchical cluster analysis (HCA). The experimental and theoretical angles were analyzed by simple linear regression, and statistical parameters (correlation coefficients, significance, and predictability) were evaluated to determine the accuracy of the calculations. The statistical analysis exhibited a good correlation and high predictive power for the DFT (B3LYP) method in the 6-31G** basis set.
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
Abstract:
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.
A produ??o do conhecimento nas Ciências Sociais e a provisoriedade da realidade material e simbólica
Osterne, Maria do Socorro F.;Brasil, Glaucíria Mota;Almeida, Rosemary de Oliveira;
Servi?o Social & Sociedade , 2013, DOI: 10.1590/S0101-66282013000100007
Abstract: this article deals with the controversies and contradictions that have followed the discussions about the scientific character in the field of social sciences and its paradigmatic controversies in order to think about the social reality. it supports the idea of the becoming, the historicity and the ideological nature of the process of knowledge, as well as the absence of a single scientific method. it emphasizes the relationship between subject and object in the process of objectification of knowledge and the link with the empirical, having in mind that objectivity is the utopia of science. finally, it stresses the requirements of the scientific method in relation to the constitution of flexible and rigorous methods that consider the dynamics and the temporary character of the material and symbolic reality.
A produ o do conhecimento nas Ciências Sociais e a provisoriedade da realidade material e simbólica The production of knowledge in Social Sciences and the temporary aspect of the material and symbolic reality
Maria do Socorro F. Osterne,Glaucíria Mota Brasil,Rosemary de Oliveira Almeida
Servi?o Social & Sociedade , 2013,
Abstract: O presente artigo aborda as polêmicas e contradi es que têm acompanhado as discuss es acerca da cientificidade no campo das Ciências Sociais e suas controvérsias paradigmáticas no intuito de pensar a realidade social. Advoga a ideia do devir, a historicidade e o caráter ideológico do processo de conhecimento, além da inexistência de um único método científico. Destaca a rela o sujeito e objeto no processo de objetiva o do conhecimento e do vínculo com o empírico, sem esquecer que a objetividade é a utopia da ciência. Por fim, enfatiza as exigências do método científico, na condi o de constitui o de métodos rigorosos e flexíveis que consideram a dinamica e a provisoriedade da realidade material e simbólica. This article deals with the controversies and contradictions that have followed the discussions about the scientific character in the field of Social Sciences and its paradigmatic controversies in order to think about the social reality. It supports the idea of the becoming, the historicity and the ideological nature of the process of knowledge, as well as the absence of a single scientific method. It emphasizes the relationship between subject and object in the process of objectification of knowledge and the link with the empirical, having in mind that objectivity is the utopia of Science. Finally, it stresses the requirements of the scientific method in relation to the constitution of flexible and rigorous methods that consider the dynamics and the temporary character of the material and symbolic reality.
Mental Health Care Given to Children and Adolescents in the Center for Children and Your Psychosocial: From the Perspective of Health Professionals  [PDF]
Máguida Gomes da Silva, Ana Ruth Macêdo Monteiro, Katyuscia Morais Barros, Sarah Maria de Sousa Feitoza, Violante Augusta Batista Braga, Cristiana Brasil de Almeida Rebou?as
Health (Health) , 2015, DOI: 10.4236/health.2015.76083
Abstract: This study was carried out in order to investigate the professionals’ feelings concerning the care in the Center for Children and Youth Psychosocial Care, as well as to evidence the advantages and difficulties of this work. This was a qualitative research guided by the social phenomenology of Al-fred Schütz. 13 health professionals from CAPSi between November 2008 and January 2009 were interviewed. We identified three categories: First feelings, difficulties of care and motivation for the care. The first category, awakened feelings, relates to the beginning of work with children and adolescents in CAPSi. The second motivation for the care, relates to the points highlighted as conducive to work. The third, difficulties in Caring for expressing the difficulties encountered in mental health of children and adolescents in CAPSi. We concluded that the care depends of knowledge, experience and service conditions in order to attend the needs of children and adolescents in CAPSi.
índices de sele??o no aprimoramento simultaneo dos componentes da produ??o de frutos em a?aizeiro
Teixeira, Davi Henrique Lima;Oliveira, Maria do Socorro Padilha de;Gon?alves, Flávia Maria Avelar;Nunes, José Airton Rodrigues;
Pesquisa Agropecuária Brasileira , 2012, DOI: 10.1590/S0100-204X2012000200012
Abstract: the objective of this work was to determine the most appropriate strategy to simultaneously increase fruit production components of assai palm (euterpe oleracea). an experiment with 25 half-sib progenies was carried out in the county of santa isabel, pa, brazil, using a randomized complete block design with four replicates and five plants per plot. the smith & hazel, williams, and mulamba & mock's selection indexes were applied in three selective strategies. the coefficients of genetic variation, heritability, the ratio between the genetic correlation of the trait under selection and fruit yield, and the sum of all genetic correlations between the traits that comprise the index and fruit yield were used as economic weights. weighting of the correlation ratio allowed the selection indexes to discriminate the best progenies in the different selection strategies evaluated. simultaneous selection by the mulamba & mock index, as to the number of fruiting months, number of bunches harvested, fruit yield, and number of rachilles per bunch, robustly estimates genetic gains.
Growth performance of Nile tilapia, Oreochromis niloticus, fingerlings reared in Na2CO3 limed waters = Desempenho produtivo de alevinos de tilápia nilótica, Oreochromis niloticus, em aquários submetidos à calagem com Na2CO3
Davi de Holanda Cavalcante,Renan Loiola Barros,Marcelo Vinícius do Carmo e Sá
Acta Scientiarum : Animal Sciences , 2010,
Abstract: Current experiment was undertaken during 6 weeks with Nile tilapia,Oreochomis niloticus, fingerlings (1.28 . 0.03 g) to assess the effects of moderate Na2CO3 liming on water quality and fish growth performance. Twenty-four 25 L-aquaria, with 15 fish per aquarium, were used, of which twelve aquaria were placed in the lab’s indoor room and twelve in the outdoor area. Two types of water (clear or green) and three different water-quality managements (none, HCl acidification and Na2CO3 liming) were simultaneously evaluated in a 3 x 2 factorial design. Total ammonia, calcium hardness, pH and total alkalinity in the green water aquaria were significantly higher than rates in the clear water aquaria. Slight liming acid water with Na2CO3 did not produce any significant effect on its water calcium hardness. No significant differences between controls and theexperimental group were observed for any growth variables. Lime rearing water with Na2CO3 has no significant effect on tilapia growth performance if the initial total alkalinity of water is higher than 20 mg CaCO3 L-1. O presente estudo foi realizado por seis semanas com alevinos de tilápia do Nilo, Oreochromis niloticus (1,28 . 0,03 g), para avaliar os efeitos da calagem moderada da água de cultivo com Na2CO3 naqualidade da água e no desempenho produtivo dos peixes cultivados. Vinte e quatro aquários de polietileno de 25 L foram utilizados para manter os peixes experimentais (15 peixes por aquário). Doze aquários foram instalados na sala interna do laboratório e 12 aquários na área externa. Dois tipos de águas (claras, sem fitoplancton ou verdes,ricas em fitoplancton) e três diferentes manejos de qualidade de água (nenhum, acidifica o com HCl ou calagem com Na2CO3) foram avaliados simultaneamente em delineamento fatorial 3 x 2. A concentra o de am nia total, dureza cálcica, pH e alcalinidade total das águas verdes foram significativamente maiores que para as águas claras. A calagem das águas fracamente ácidas com Na2CO3 n o produziu nenhumefeito significativo na dureza cálcica da água. N o se observaram diferen as significativas entre os grupos-controle e o grupo experimental para nenhuma das variáveis de desempenho produtivo observadas. Concluiu-se que fazer a calagem da água de cultivo de tilápias com Na2CO3 n o trará nenhum benefício ao desempenho zootécnico dos peixes se a alcalinidade inicial da água exceder 20 mg L-1 de CaCO3.
Os aportes sócio-políticos da educa??o nutricional na perspectiva de um envelhecimento saudável
Alencar, Maria do Socorro Silva;Barros Júnior, Francisco de Oliveira;Carvalho, Cecília Maria Resende Gon?alves de;
Revista de Nutri??o , 2008, DOI: 10.1590/S1415-52732008000400001
Abstract: objective: this article analyzes the socio-political contribution of nutrition education in promoting health. methods: this is a ludo-educational workshop on nutrition, health and aging with elderly who attend a weekly university course for seniors. the study was of the exploratory and descriptive type, inserted in the qualitative modality, based on participant observation and semi-structured interview. the objective was to grasp the concepts, attitudes and reflections of the subjects regarding eating practices, lifestyle and aging process. results: the elderly stated that what motivated them to participate in the program and attend the workshop was the opportunity to learn, socialize and look after their health. their concepts on how nutrition education contributes to promote health were categorized in the following themes: functional capacity and self-care. conclusion: the results lead us to reflect on education for the elderly, emphasizing the socio-political dimensions of nutrition education as it affects eating habits and lifestyle throughout life. the interdisciplinary actions that aim to preserve, maintain or promote functional capacity of the elderly are likely to improve the quality of life of the aging population.
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