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Search Results: 1 - 10 of 240375 matches for " Luiz Antonio d’Avila "
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Validation and Comparison of Calibration Techniques for Measurements of Carbon Dioxide in Atmospheric Air Standards  [PDF]
Andreia de Lima Fioravante, Cristiane Rodrigues Augusto, Valnei Smar?aro da Cunha, Luiz Antonio dAvila
Journal of Environmental Protection (JEP) , 2018, DOI: 10.4236/jep.2018.91004
Abstract: The increase in the concentration of carbon dioxide (CO2) in the atmosphere has led the scientific community to investigate the adverse effects on humanity and nature, including the greenhouse effect, which contributes to global warming and can lead to climate change, besides the risks associated with human health. Due to the importance of metrological issues in the current scenario, the Laboratory of Gas Analysis (Lanag) of the National Institute of Metrology, Quality and Technology (Inmetro) is developing the methodology of preparation of such primary standard gas mixtures through gravimetry. For the preparation of these standards, an analysis verification step is necessary, carried out by means of an analytical technique of comparison, at low levels of concentration, by cavity ringdown (CRDS) and by gas chromatography using a flame ionization detector coupled to a methaniser catalyst (GC-FIDmeth). This work presents the method validation of both methodologies developed to analyze a range of concentration of atmospheric standards of CO2 at a matrix of synthetic clean dry air (SCDA) by CRDS and GC-FIDmeth, of which the analysis results can compromise the measurements on atmospheric air quality. The objective is to compare results of method validation of both analytical methods for low CO2 concentration through the use of primary reference mixtures developed and also by certified reference material. The validation measurement results were analyzed according to the requirements of ISO 5725: 1994 parts 1 and 2, and the calculation of measurement uncertainty followed the methodology described in ISO 6143:2001, with results showing satisfactory consistent between both selected techniques. According to the work presented here, the obtained validation results for CRDS are better than the GC results, such as the relative uncertainty of samples evaluated for CRDS was 0.4% and 2.7% for GC_FID meth.
Pyrolysis Oil from the Fruit and Cake of Jatropha curcas Produced Using a Low Temperature Conversion (LTC) Process: Analysis of a Pyrolysis Oil-Diesel Blend  [PDF]
Monique Kort-Kamp Figueiredo, Gilberto Alves Romeiro, Raquel Vieira Santana Silva, Priscila Alvares Pinto, Raimundo Nonato Damasceno, Luiz Antonio d`Avila, Amanda P. Franco
Energy and Power Engineering (EPE) , 2011, DOI: 10.4236/epe.2011.33041
Abstract: Background: The LTC process is a technique that consists of heating solid residues at a temperature of 380oC - 420oC in an inert atmosphere and their products are evaluated individually: these products include pyrolysis oil, pyrolytic char, gas and water. The objective of this study was to compare the effects of the use of oils obtained by pyrolysis of Jatropha curcas as an additive for diesel in different proportions. Results: A Low Temperature Conversion (LTC) process carried out on samples of Jatropha curcas fruit and generated pyrolysis oil, pyrolyic char, gas and aqueous fractions in relative amounts of 23, 37, 16 and 14% [w/w] respectively for Jatropha curcas fruit and 19, 47, 12 and 22% [w/w] respectively for Jatropha curcas cake. The oil fractions were analyzed by FTIR, 1H NMR, 13C NMR, GCMS and physicochemical analysis. The pyrolysis oil was added to final concentrations of 2, 5, 10 and 20% [w/w] to commercial diesel fuel. The density, viscosity, sulfur content and flash point of the mixtures were determined. Conclusions: The results indicated that the addition of the pyrolysis oil maintained the mixtures within the standards of the diesel directive, National Petroleum Agency (ANP no 15, of 19. 7. 2006), with the exception of the viscosity of the mixtures containing 20% pyrolysis oil.
Alternative extraction of alkaloid anticarcinogens from Brazilian "vinca rosea" using Ion exchange chromatography
Carvalhaes, Sérgio Freire de;Costa, Daniela Lucena;Mazzei, José Luiz;Taddei, Luiz Eduardo Martins;d'Avila, Luiz Antonio;
Revista Brasileira de Farmacognosia , 2002, DOI: 10.1590/S0102-695X2002000300041
Abstract: extracts in ethanol and ethanol-ammonia of dried leaves from catharanthus roseus, gathered at rio de janeiro state, were adsorbed in a strongly acidic cation exchange resin with sulfonic acid group, using the finite bath method, resulting in an alkaloid retained fraction and an acidic and neutral unretained fraction. high performance liquid chromatography showed the isolation of the alkaloid fraction to be highly selective and with good performance, with an absence of alkaloids in the unretained fraction, while the retained fraction presented 1,54-6,35 mg/g of vindoline and 0,12-0,91 mg/g of vinblastine, common for an alkaloid-rich concentrate, usually obtained by classic extraction with several steps using solvents.
Análise comparativa da concentra??o industrial e de turnover da indústria farmacêutica no Brasil para os segmentos de medicamentos de marca e genéricos
Rosenberg, Gerson;Fonseca, Maria da Gra?a Derengowski;d' Avila, Luiz Antonio;
Economia e Sociedade , 2010, DOI: 10.1590/S0104-06182010000100005
Abstract: this paper analyzes the evolution of brand-name and generic drugs structure in brazil since 1997. after the introduction of generic drugs it was not verified a significant decrease in the concentration of brazilian pharmaceutical industry. the process of mergers and acquisitions in the 90's enhanced the process of concentration in the international market. however, a non-expressive turnover can be demonstrated in both pharmaceutical and generic markets. at the same time, the entrance of the generic industry in brazil explains the invigoration of the national industry. the mergers and acquisitions process in the pharmaceutical industry is quite intense in europe and in the usa, although in brazil it is still not significant.
Occurrence of Antimicrobials in River Water Samples from Rural Region of the State of Rio de Janeiro, Brazil  [PDF]
Mychelle Alves Monteiro, Bernardete Ferraz Spisso, Julia Rodrigues Martins Pastor dos Santos, Rafaela Pinto da Costa, Rosana Gomes Ferreira, Mararlene Ulberg Pereira, Talita da Silva Miranda, Bárbara Rodrigues Geraldino de Andrade, Luiz Antonio dAvila
Journal of Environmental Protection (JEP) , 2016, DOI: 10.4236/jep.2016.72020
Abstract: The occurrence of antimicrobials in the aquatic environment and drinking water has raised the question of their impact on the environment and public health. Animal production is one of the most expressive activities of Brazilian agribusiness. In order to ensure the productivity and competitiveness of the sector, the use of drugs for therapeutic and prophylactic purposes is a common practice. Due to the continuous release of antimicrobials into the environment, the aim of this study was to compare the frequency of detection of tetracyclines and sulfonamides in surface water collected from rural areas in Lidice District of Rio Claro, in the State of Rio de Janeiro, Brazil. An investigative study was conducted with 24 river water samples analyzed by high-performance liquid chromatography coupled to tandem mass spectrometry and the aim of this study was to determine residues of sulfonamides and tetracyclines based on the USEPA method 1694. The results indicated the presence of sulfamethoxazole and oxytetracycline concentrations at the ng·L-1 level. The applied method showed overall good performance with recoveries above 57%, method detection limits ≤ 7.17 ng·L-1, method quantification limits ≤ 23.90 ng·L-1 and good linearity.
A codifica??o moral da medicina: avan?os e desafios na forma??o dos médicos
Luiz d'Avila, Roberto;
Revista Brasileira de Saúde Materno Infantil , 2010, DOI: 10.1590/S1519-38292010000600019
Abstract: the aim of this article is to discuss how the moral code for medicine is produced and to demonstrate the need for technical training to be expanded to include humanitarian features. to this end, it first addresses medicine as a science and as an art founded on moral principles. then, it reviews the historical context of the production of the moral codes for medicine, with a specific focus on brazil. finally, it discusses the prevailing medical code, pointing out the importance of not regarding it as a strictly punitive tool, but as a set of guidelines for the promotion of the well-being of patients and the improvement of society in general. it concludes by indicating the need for medical schools to go beyond technical training and provide on-going preparation for dealing with humanitarian issues, thereby developing the sense of morality among the students and future doctors.
Desenvolvimento e aplica??o de metodologia por cromatografia em camada delgada para determina??o do perfil de alcalóides oxindólicos pentacíclicos nas espécies sul-americanas do gênero Uncaria
Valente, Ligia M.M.;Alves, Flaviane F.;Bezerra, Giselle M.;Almeida, Maria Beatriz S.;Rosario, Sandra L.;Mazzei, José L.;d'Avila, Luiz A.;Siani, Antonio C.;
Revista Brasileira de Farmacognosia , 2006, DOI: 10.1590/S0102-695X2006000200015
Abstract: the species uncaria tomentosa (willd.) dc. and u. guianensis gmel. (rubiaceae), known as cat's claw, are large woody vines occurring in the amazon rain forest and other tropical areas of south and central america. it has been used medicinally by indigenous peoples for at least 2,000 years for several diseases. tetra- and pentacyclic oxindole alkaloids, triterpenoid glycosides, sterols and flavonoids are found in these plants. among these metabolites, six pentacyclic oxindole alkaloids, speciophylline, mitraphylline, pteropodine, uncarine f, isopteropodine and isomitraphylline, are considered to be the biochemical markers and are used to standardize commercial herbal medicines. the present study describes the development of an analytical methodology to determine the profile of these alkaloid markers through thin layer chromatography (tlc). this development has also included a comparison among the use of the crude methanol extract and fractions obtained through the classical acid-base partition or by using the basic resin polyamide 6. silica gel was used as stationary phase with the variation of some parameters such as solvent systems, sample concentration, distance of development and detection method. the tlc method developed was shown to be reliable, reproducible and selective for the target alkaloids. it has been applied to the analysis of leaves and stems from both species as well as phytopharmaceutical derivatives based on u. tomentosa.
Determination of phenobarbital in human plasma by a specific liquid chromatography method: application to a bioequivalence study
Dalmora, Sérgio Luiz;Sangoi, Maximiliano da Silva;Nogueira, Daniele Rubert;D'Avila, Felipe Bianchini;Moreno, Ronílson Agnaldo;Sverdloff, Carlos Eduardo;Oliveira, Rogério Antonio de;Borges, Ney Carter;
Química Nova , 2010, DOI: 10.1590/S0100-40422010000100023
Abstract: a liquid chromatography method was developed and validated for the determination of phenobarbital in human plasma using phenytoin as internal standard. the drugs were extracted from plasma by liquid-liquid extraction and separated isocratically on a c12 analytical column, maintained at 35 oc, with water:acetonitrile:methanol (58.8:15.2:26, v/v/v) as mobile phase, run at a flow rate of 1.2 ml/min with detection at 205 nm. the method was linear in the range of 0.1-4 μg/ml (r2=0.9999) and demonstrated acceptable results for the precision, accuracy and stability studies. the method was successfully applied for the bioequivalence study of two tablet formulations (test and reference) of phenobarbital 100 mg after single oral dose administration to healthy human volunteers.
Estudo comparativo da microvasculariza??o das pregas vocais humanas acometidas por cisto e rea??o nodular contra-lateral sob endoscopia rígida
D'Avila, Jeferson Sampaio;Sennes, Luiz Ubirajara;Tsuji, Domingos Hiroshi;
Revista Brasileira de Otorrinolaringologia , 2003, DOI: 10.1590/S0034-72992003000200004
Abstract: aim: the aim of this study was to analyze microvascular alterations that occur in the human vocal fold (vf), when damaged by cyst and contralateral nodule reaction. study design: clinical prospective. material and method: through laryngoscope of suspension the vfs were analyzed by rigid endoscopy in anterior, medium, posterior and subglotic regions. the microvascular alterations were classified in four major groups: parallel, transversal, branched and puntiform. theses were subdivided into twelve types. result: in vfs damaged by cyst, the microvascular alterations were more frequent (93,1%) rather than in contralateral vfs damaged by nodule reaction (6,9%). in the occurrence of cyst were also observed multiple microvascular alterations (10 subtypes), having prevalence of sinuous and ectasical microvessels, while in vfs damaged by contralateral nodule reaction these microvessels alterations were less varied (3 subtypes). when straight related to nodular lesion, those were exclusively puntiform. conclusion: our findings emphasize that the presence of cyst in the blade itself interferes in the arrangements of the microvessels of the vfs, while nodular reaction that compromises the epithelium, which is more superficial than the vessels, interferes in a minor degree in the vascular architecture. therefore in the occurrence of altered microvessels diagnosis of the cyst in more likely rather than the nodule reaction.
Estudo comparativo da microvasculariza o das pregas vocais humanas acometidas por cisto e rea o nodular contra-lateral sob endoscopia rígida
D'Avila Jeferson Sampaio,Sennes Luiz Ubirajara,Tsuji Domingos Hiroshi
Revista Brasileira de Otorrinolaringologia , 2003,
Abstract: OBJETIVO: O objetivo desse estudo foi analisar as altera es microvasculares que ocorrem na prega vocal (PV) humana, quando acometida por cisto e rea o nodular contra-lateral. FORMA DE ESTUDO: Clínico prospectivo. MATERIAL E MéTODO: Através de laringoscopia de suspens o as PVs foram analisadas sob endoscopia rígida em suas por es anterior, média, posterior e sub-glótica. As altera es da microvasculariza o foram classificadas em quatro grandes grupos: Paralelo, Transversal, Ramificado e Puntiforme. Estas foram subdivididas em doze subtipos. RESULTADOS: Nas PVs acometidas por cisto as altera es microvasculares foram mais freqüentes (93,1%) do que nas PVs contra-laterais acometidas por rea o nodular (6,9%). Na presen a de cisto também foram observadas múltiplas altera es microvasculares (10 subtipos), havendo predominancia de microvasos tortuosos e ectásicos, enquanto nas acometidas por rea o nodular contra-lateral essas altera es foram menos variadas (3 subtipos). Quando diretamente relacionadas à les o nodular, foram com exclusividade puntiformes. CONCLUS O: Nossos achados sugerem que a presen a do cisto na lamina própria interfere no arranjo dos microvasos das PVs, enquanto a rea o nodular, por acometer o epitélio, que é mais superficial aos vasos, interfere em menor grau em rela o à arquitetura vascular. Deste modo na presen a de microvasos alterados devemos suspeitar mais do diagnóstico de cisto do que de rea o nodular.
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