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Search Results: 1 - 10 of 528011 matches for " Maria A. Eva;Cordeiro "
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Efeito do sombreamento no crescimento inicial de Lonchocarpus muehlbergianus Hassl
Cancian, Maria A. Eva;Cordeiro, Lázara;
Acta Botanica Brasilica , 1998, DOI: 10.1590/S0102-33061998000400005
Abstract: this experiment was carried out under greenhouse conditions to verifiy the influence of shading on the growth of lonchocarpus muehlbergianus plants. the following shading levels were used: 40% and 60% obtained using black plastic screening, and 0% under full light. the following results were obtained: the plants cultivated in 60% shading were higher and present larger leaf areas, wider collar and main root diameters, besides larger aerial and dry root weight were obtained in plants cultivated in 0% and 40% shading.
Structure and weak hydrogen bonds in liquid acetaldehyde
Cordeiro, Maria A. M.;Cordeiro, Jo?o M. M.;
Journal of the Brazilian Chemical Society , 2004, DOI: 10.1590/S0103-50532004000300003
Abstract: monte carlo simulations have been performed to investigate the structure and hydrogen bonds formation in liquid acetaldehyde. an all atom model for the acetaldehyde have been optimized in the present work. theoretical values obtained for heat of vaporisation and density of the liquid are in good agreement with experimental data. graphics of radial distribution function indicate a well structured liquid compared to other similar dipolar organic liquids. molecular mechanics minimization in gas phase leads to a trimer of very stable structure. the geometry of this complex is in very good agreement with the rdf. the shortest site-site correlation is between oxygen and the carbonyl hydrogen, suggesting that this correlation play a important role in the liquid structure and properties. the o×××h average distance and the c-h×××o angle obtained are characteristic of weak hydrogen bonds.
Structure and weak hydrogen bonds in liquid acetaldehyde
Cordeiro Maria A. M.,Cordeiro Jo?o M. M.
Journal of the Brazilian Chemical Society , 2004,
Abstract: Monte Carlo simulations have been performed to investigate the structure and hydrogen bonds formation in liquid acetaldehyde. An all atom model for the acetaldehyde have been optimized in the present work. Theoretical values obtained for heat of vaporisation and density of the liquid are in good agreement with experimental data. Graphics of radial distribution function indicate a well structured liquid compared to other similar dipolar organic liquids. Molecular mechanics minimization in gas phase leads to a trimer of very stable structure. The geometry of this complex is in very good agreement with the rdf. The shortest site-site correlation is between oxygen and the carbonyl hydrogen, suggesting that this correlation play a important role in the liquid structure and properties. The OxxxH average distance and the C-HxxxO angle obtained are characteristic of weak hydrogen bonds.
Short-Time Derivatization Method for Analysis of Abamectin in Water Using High-Performance Liquid Chromatography Coupled to Fluorescence Detector  [PDF]
Daniela Cordeiro, Luciana Teresa Dias Cappelini, Raphael Teixeira Verbinnen, Gustavo Henrique Louren?o Vicente, Andréa Novelli, Evaldo Luiz Gaeta Espíndola, Eny Maria Vieira
American Journal of Analytical Chemistry (AJAC) , 2014, DOI: 10.4236/ajac.2014.516117
Abstract: A method using a short-time derivatization step for the assessment of abamectin in water is presented. Abamectin derivative stable up to 7 days was obtained. Some regions where orange crops are present have received abamectin doses, aiming to increase the productivity and to combat pests and weeds, even when its residues reach the aquatic environment and interfere on water quality. Water samples from Jacaré-Pepira River (Brotas City, Brazil) nearby orange crops around urban zone, were evaluated for the presence of abamectin. The analytical method was validated resulting recovery around 108%, precision of 12%, accuracy of 104%, correlation coefficient of 0.9945, and detection and quantification limits of 0.1 μg·L﹣1 and 0.2 μg·L﹣1, respectively. Stable abamectin derivative was reached after 60 min of derivatization at room temperature (25°C). No abamectin residues were found into samples.
A Metamodel for Agile Requirements Engineering  [PDF]
Eva-Maria Sch?n, Jorge Sede?o, Manuel Mejías, J?rg Thomaschewski, María José Escalona
Journal of Computer and Communications (JCC) , 2019, DOI: 10.4236/jcc.2019.72001
Abstract: Value delivery is becoming an important asset for an organization due to increasing competition in industry. Therefore, companies apply Agile Software Development (ASD) to be more competitive and reduce time to market. Using ASD for the development of systems implies that established approaches of Requirements Engineering (RE) undergo some changes in order to be more flexible to changing requirements. To this end, the field of agile RE is emergent and different process models for agile RE have arisen. The aim of this paper is to build an abstract layer about the variety of existing process models by means of a metamodel for agile RE. It has been created in several iterations and relies on the evaluation of related process models. Furthermore, we have derived process models for agile RE in industry by presenting instances of the metamodel in two different cases: one is based on Scrum whereas the other is based on Kanban. This paper contributes to the software development body of knowledge by delivering a metamodel for agile RE that supports researchers and practitioners modeling and improving their own process models. We can conclude that the agile RE metamodel is highly relevant for the industry as well as for the research community, since we have derived it following empirical research in the field of ASD.
Coopera??o internacional na área da Saúde Coletiva: propostas para um debate
Loyola,Maria Andréa; Corrêa,Marilena Cordeiro Dias Villela; Guimar?es,Eduardo Ribas De Biase;
Ciência & Saúde Coletiva , 2010, DOI: 10.1590/S1413-81232010000400015
Abstract: in the available literature, there is no study devoted to international cooperation in public health. this paper aims to partly fill this gap, raising and examining the state of art in this area as well as how it interferes in the evaluation of post-graduate programs. the study used secondary data available at capes "indicators journals", during the years of 1998 to 2006. it also analyzes foreign scholarships and special programs of cooperation of capes from 2005 to 2009 through a quantitative descriptive methodology. it shows that international cooperation in the area is relatively developed in a variety of themes and diverse partnerships, focusing in the united states. it is observed a positive correlation between the number of international cooperation and a high-concept program into the evaluation of capes, the last triennium of evaluation. the sub-areas where there is more cooperation are, in order: epidemiology; planning, and others. there is a variety of institutions, themes and subareas involved in international cooperation that could be a positive indicator in the evaluation, but as far as was possible to infer, no significant correlation in this direction was found.
Breakdown of adiabatic transfer of light in waveguides in the presence of absorption
Eva-Maria Graefe,Alexei A. Mailybaev,Nimrod Moiseyev
Physics , 2012, DOI: 10.1103/PhysRevA.88.033842
Abstract: In atomic physics, adiabatic evolution is often used to achieve a robust and efficient population transfer. Many adiabatic schemes have also been implemented in optical waveguide structures. Recently there has been increasing interests in the influence of decay and absorption, and their engineering applications. Here it is shown that even a small decay can significantly influence the dynamical behaviour of a system, above and beyond a mere change of the overall norm. In particular, a small decay can lead to a breakdown of adiabatic transfer schemes, even when both the spectrum and the eigenfunctions are only sightly modified. This is demonstrated for the generalization of a STIRAP scheme that has recently been implemented in optical waveguide structures. Here the question how an additional absorption in either the initial or the target waveguide influences the transfer property of the scheme is addressed. It is found that the scheme breaks down for small values of the absorption at a relatively sharp threshold, which can be estimated by simple analytical arguments.
Reliable Classifier to Differentiate Primary and Secondary Acute Dengue Infection Based on IgG ELISA
Marli Tenório Cordeiro, Ulisses Braga-Neto, Rita Maria Ribeiro Nogueira, Ernesto T. A. Marques
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0004945
Abstract: Background Dengue virus infection causes a wide spectrum of illness, ranging from sub-clinical to severe disease. Severe dengue is associated with sequential viral infections. A strict definition of primary versus secondary dengue infections requires a combination of several tests performed at different stages of the disease, which is not practical. Methods and Findings We developed a simple method to classify dengue infections as primary or secondary based on the levels of dengue-specific IgG. A group of 109 dengue infection patients were classified as having primary or secondary dengue infection on the basis of a strict combination of results from assays of antigen-specific IgM and IgG, isolation of virus and detection of the viral genome by PCR tests performed on multiple samples, collected from each patient over a period of 30 days. The dengue-specific IgG levels of all samples from 59 of the patients were analyzed by linear discriminant analysis (LDA), and one- and two-dimensional classifiers were designed. The one-dimensional classifier was estimated by bolstered resubstitution error estimation to have 75.1% sensitivity and 92.5% specificity. The two-dimensional classifier was designed by taking also into consideration the number of days after the onset of symptoms, with an estimated sensitivity and specificity of 91.64% and 92.46%. The performance of the two-dimensional classifier was validated using an independent test set of standard samples from the remaining 50 patients. The classifications of the independent set of samples determined by the two-dimensional classifiers were further validated by comparing with two other dengue classification methods: hemagglutination inhibition (HI) assay and an in-house anti-dengue IgG-capture ELISA method. The decisions made with the two-dimensional classifier were in 100% accordance with the HI assay and 96% with the in-house ELISA. Conclusions Once acute dengue infection has been determined, a 2-D classifier based on common dengue virus IgG kits can reliably distinguish primary and secondary dengue infections. Software for calculation and validation of the 2-D classifier is made available for download.
Ruptura traumática de via aérea em crian?a: um desafio diagnóstico
Ventura, Andréa Maria Cordeiro;Góes, Patrícia Freitas;Otoch, José Pinhata;Fernandes, José Carlos;
Jornal de Pediatria , 2005, DOI: 10.1590/S0021-75572005000300016
Abstract: objective: to report a case of airway disruption in a child victim of blunt thoracic trauma due to falling off a sink. description: descriptive case report. a 34-month old boy victim of thoracic trauma was seen at the pediatric intensive care unit of a university hospital. plain chest radiograph, thoracic computed tomography, bronchoscopy, thoracotomy, antibiotics, hemodynamic and respiratory support were performed. plain chest radiograph, thoracic computed tomography and bronchoscopy were performed in order to arrive at a precise diagnosis of traumatic airway disruption associated with pulmonary contusion, pneumothorax, mediastinal and subcutaneous emphysema. the patient underwent thoracotomy for surgical repair of an almost complete disruption of the left main bronchus. antibiotics and ventilatory support contributed to a favorable outcome without medium-term sequelae. comments: children presenting with thoracic trauma must be investigated for uncommon, but potentially lethal injuries, such as tracheobronchial disruption, particularly in cases where there is strong clinical evidence. diagnostic workup should be optimized with plain chest radiograph and thoracic computed tomography, while bronchoscopy will confirm the definitive diagnosis.
Bee community of a beach dune ecosystem on Maranh?o Island, Brazil
Albuquerque, Patricia Maia Correia de;Camargo, Jo?o Maria Franco de;Mendon?a, José ?ngelo Cordeiro;
Brazilian Archives of Biology and Technology , 2007, DOI: 10.1590/S1516-89132007000700012
Abstract: the bee-plant community in a beach dune ecosystem in north-eastern of brazil was studied concerning phenology and floral preference. the bees visited thirty-three species of 20 families of plants. the most visited species were vernonia arenaria (asteraceae), chamaecrista hispidula (caesalpiniaceae), passiflora foetida (passifloraceae) and turnera melochioides (turneraceae). fifty-five percent of plants presented an annual or long flowering period (from 5 to 7 months). the largest number of species blooming was observed from march to august (dry season), corresponding to the period of greatest abundance and diversity of bees. based on the range of floral sources used by the dominant bees, three guilds of bees were noted: bees with a restricted range of floral sources: melitoma segmentaria, centris tarsata, centris flavifrons, ceratinula sp.; moderate generalists: megachile (leptorachis) sp., euglossa cordata, augochlorella sp., eulaema nigrita and xylocopa frontalis; and generalists: xylocopa cearensis, apis mellifera, exomalopsis analis and pseudaugochloropsis pandora.
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