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Search Results: 1 - 10 of 4578 matches for " Edisson; Delgado "
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Bioactividad del aceite esencial de Chenopodium ambrosioides colombiano
Jaramillo C,Beatriz E; Duarte R,Edisson; Delgado,Wilman;
Revista Cubana de Plantas Medicinales , 2012,
Abstract: introduction: plants have developed self-protecting chemical mechanisms to avoid being attacked by insects, fungi, bacteria, and viruses. the diseases caused by these pests are controlled with pesticides of high toxicity, therefore, it is necessary to use alternative compounds like essential oils. essential oils are potential botanical sources of compounds having the same function as the pesticides. however, they have some advantages over the latter such as low toxicity for mammal, high volatility and toxicity for pests and microorganisms which attack stored products. its volatile insecticidal property made it to be known as fumigant. chenopodium ambrosioides l. (chenopodiaceae) has been reported for its potential antiparasitic properties, including antiprotozoal activity. objective: this study determine the fumigant, antifungal, and antioxidant activities of essential oils isolated from chenopodium ambrosioides l. and their volatile chemical composition. methods: the essential oil (eo) was obtained from leaves of c. ambrosioides by hydrodistillation whereas the volatile chemical composition was determined by gas chromatography coupled with mass spectrometry detector (gc-ms). the fumigant activity assay of the essential oil was performed against sitophilus zeamais. the antifungal activity on plant pathogenic fungus (fusarium oxysporum f. sp. dianthi) and the antioxidant potential were determined through the discoloration test of dpph. radical. results: the major component found in the essential oil from c. ambrosioides was a-terpinene (60.29 %), followed by p-cymene (20.49 %), 4-carene (7.96 %) and trans-ascaridol (1.91 %). c. ambrosioides was active against fusarium oxysporum, with a mycelial inhibition of 97.3 % at 176.5 μl eo/l air after 72 h of exposure; and a mortality rate against sitophilus zeamais of 100% at 500 μl of essential oil per air liter after 24 h of exposure. the inhibition percentage of dpph? radical was 84.89 %. conclusions: this study demonstrat
Bioactividad del aceite esencial de Chenopodium ambrosioides colombiano Bioactivity of essential oil from Colombian Chenopodium ambrosioides
Beatriz E Jaramillo C,Edisson Duarte R,Wilman Delgado
Revista Cubana de Plantas Medicinales , 2012,
Abstract: Introducción: las plantas tienen mecanismos químicos de autoprotección para evitar ser atacadas por insectos, hongos, bacterias y virus. Las enfermedades producidas por estas plagas son controladas con plaguicidas, que presentan alta toxicidad; por esto, es necesario usar compuestos alternativos como aceites esenciales. Estas sustancias son fuentes botánicas potenciales que cumplen la misma función de los plaguicidas, con la ventaja de que presentan baja toxicidad para los mamíferos, alta volatilidad y toxicidad para los insectos y microorganismos que atacan los productos de cosecha almacenados, por ser volátiles su propiedad insecticida se conoce como fumigante. Chenopodium ambrosioides L. (Chenopodiaceae) ha sido reportada por sus potentes propiedades antiparasitarias, incluida la actividad antiprotozoaria. Objetivo: determinar la actividad fumigante, antifúngica y antioxidante del aceite esencial de Chenopodium ambrosioides y su composición química volátil. Métodos: el aceite esencial fue obtenido de hojas de C. ambrosioides por hidrodestilación, la composición química volátil se determinó mediante cromatografía de gases acoplada a espectrometría de masas. El ensayo de actividad fumigante del aceite esencial se realizó sobre Sitophilus zeamais. La actividad antifúngica sobre el hongo fitopatógeno Fusarium oxysporum f. sp. Dianthi, y la capacidad antioxidante se efectuómediante el ensayo de decoloración del radical DPPH. Resultados: el compuesto mayoritario encontrado en aceite esencial de C. ambrosioides fue a-terpineno (60,29 %), seguido de p-cimeno (20,49 %), 4-careno (7,96 %) y trans-ascaridol (1,91 %). C. ambrosioides fue activo contra Fusarium oxysporum con un porcentaje de inhibición micelar de 97,3 % a 176,5 μL de aceite esencial/litro de aire, leído a las 72 h; y un porcentaje de mortalidad contra Sitophilus zeamais de 100 % a 500 μL de aceite esencial/litro de aire, después de 24 h de exposición. El porcentaje de inhibición del radical DPPH fue de 84,89 %. Conclusiones: el aceite esencial de C. ambrosioides exhibió importante actividad fungicida contra F. oxysporum y fumigante contra S. zeamais, por lo cual podría reemplazar fungicidas e insecticidas sintéticos. Introduction: plants have developed self-protecting chemical mechanisms to avoid being attacked by insects, fungi, bacteria, and viruses. The diseases caused by these pests are controlled with pesticides of high toxicity, therefore, it is necessary to use alternative compounds like essential oils. Essential oils are potential botanical sources of compounds having the same function as
Comparison among structured first order algorithms in the solution of the euler equations in two-dimensions
Maciel, Edisson Sávio de Góes;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2007, DOI: 10.1590/S1678-58782007000400011
Abstract: the present work studies upwind schemes applied to the solution of aeronautical and aerospace problems. the harten, the frink, parikh and pirzadeh, the liou and steffen and the radespiel and kroll algorithms, all first order accurate in space, are studied. the euler equations in conservative form, employing a finite volume formulation and a structured spatial discretization, in the two-dimensional space, are solved. a time splitting method and a runge-kutta method of five stages are used to perform the time march of the numerical schemes. the steady state physical problems of the supersonic flow along a ramp and around a blunt body configuration are studied. all algorithms are accelerated to the steady state solution using a spatially variable time step. this technique has proved excellent gains in terms of convergence ratio as reported in maciel. the results have demonstrated that the liou and steffen scheme has presented the most critical solutions, in both example-cases, in relation to the others schemes and a more accurate solution, in terms of the determination of the stagnation pressure in the blunt body case, than the harten and the radespiel and kroll schemes. in the ramp problem, the harten scheme predicts the best pressure distribution along the ramp wall in comparison with theoretical results. in the blunt body problem, the liou and steffen scheme presents the highest value of cp at the configuration nose in relation to the other schemes. values of cl and cd have been accurately predicted by all schemes, except by the harten scheme.
Structured high resolution algorithms in the solution of the euler equations in the two-dimensional space
Maciel, Edisson Sávio de Góes;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2008, DOI: 10.1590/S1678-58782008000200001
Abstract: the present work compares the high resolution schemes of (1) yee, warming and harten, (2) harten, (3) yee and kutler and (4) hughson and beran applied to the solution of aeronautical and aerospace problems. all schemes are tvd flux difference splitting type and are second order accurate in space. the euler equations in conservative form, employing a finite volume formulation and a structured spatial discretization, are solved in two-dimensions. the time integration is performed by a dimensional splitting method and is first order accurate. the steady state physical problems of the supersonic flows along a ramp and around a blunt body configuration are studied. in the ramp problem, the hughson and beran scheme was the most critical because presented the most intense pressure field and the most intense mach number field. moreover, this scheme predicts the best value to the shock angle of the oblique shock wave. the shock and the expansion fan pressure distributions are better captured by the yee, warming and harten and the yee and kutler schemes. in the blunt body problem, the harten scheme presented the most intense pressure field. the harten scheme estimates the best value to the stagnation pressure on the configuration nose.
Composición química volátil del aceite esencial de Eryngium foetidum L. colombiano y determinación de su actividad antioxidante
Jaramillo,Beatriz E; Duarte,Edisson; Martelo,Irina;
Revista Cubana de Plantas Medicinales , 2011,
Abstract: introduction: culantro (eryngium foetidum l., apiaceae) is a herb native to tropical america and the west indies. although widely used in dishes throughout the caribbean, latin america, and the far east. the herb is reportedly rich in calcium, iron, carotene, and riboflavin and its harvested leaves are widely used as a food flavoring and seasoning herb for meat and many other foods. their medicinal values include its use as a tea for flu, diabetes, constipation, and fevers. one of its most popular uses is in chutneys as an appetite stimulant. species of e. foetidum from several countries have shown a variable composition of its essential oil, particularly, in their leaves. objective: to establish the volatile chemical composition of the essential oil obtained from fresh leaves and stems of e. foetidum and to evaluate its antioxidant activity. methods: the essential oil was isolated by hydrodistillation. the volatile chemical composition was analyzed by gas chromatography coupled to flame ionization detector (gc-fid) and mass spectrometry (gc-ms). the antioxidant activity was determined using the test radical dpph decoloration. (2,2-diphenyl-1-picryl hidrazyl). results: the essential oil from e. foetidum showed a high percentage of aliphatic aldehydes (e-2-dodecenal, 5-dodecene, tetradecanal, tetradecenal) and aromatic (2,3,5-trimethylbenzaldehyde, trimethylphenol). the antioxidant activity was expressed as percentage inhibition of dpph. radical (89.39 %). conclusions: in the essential oil from colombian e. foetidum predominant aliphatic aldehydes and aromatic compounds. the dpph test showed that ae has antioxidant capacity, this makes it an important source of natural antioxidants.
Composición química volátil del aceite esencial de Eryngium foetidum L. colombiano y determinación de su actividad antioxidante Volatile chemical composition of the essential oil from colombian Eryngium foetidum L. and determination of its antioxidant activity
Beatriz E Jaramillo,Edisson Duarte,Irina Martelo
Revista Cubana de Plantas Medicinales , 2011,
Abstract: Introducción: el culantro (Eryngium foetidum L., Apiaceae) es una hierba nativa de América tropical y las Antillas. Es usada en diferentes recetas de comida típicas del Caribe, Latinoamérica y el lejano oriente. Estudios indican que esta planta es rica en calcio, hierro, caroteno, y riboflavina; sus hojas son utilizadas como saborizantes y condimentos de algunos alimentos. Su aplicación medicinal incluye su uso como té para la gripe, diabetes, el estre imiento y la fiebre. Se usa comúnmente en salsas como estimulante del apetito. Especies de E. foetidum de varios países han mostrado una composición variable de su aceite esencial, sobre todo, en sus hojas. Objetivo: establecer la composición química volátil del aceite esencial obtenido de hojas y tallos frescos de E. foetidum y evaluar su actividad antioxidante. Métodos: el aceite esencial fue aislado usando la técnica de hidrodestilación. La composición química volátil se determinó mediante cromatografía de gases acoplada a detectores de ionización en llama (GC-FID) y espectrometría de masas (GC-MS). La actividad antioxidante fue determinada mediante el ensayo de decoloración del radical DPPH. (2,2-difenil-1-picril hidracilo). Resultados: el aceite esencial de las hojas de E. foetidum presentó un alto porcentaje de aldehídos alifáticos (E-2-dodecenal, 5-dodeceno, tetradecanal, tetradecenal) y aromáticos (2,4,6-trimetilbenzaldehído, 3,4,5-trimetilfenol). La actividad antioxidante se expresó como porcentaje de inhibición del radical DPPH. (89,39 %). Conclusiones: en el aceite esencial de E. foetidum colombiano predominaron compuestos aldehídos alifáticos y aromáticos. El resultado del ensayo de DPPH. mostró que el aceite esencial posee una capacidad antioxidante alta, esto lo hace una fuente importante de antioxidantes naturales. Introduction: culantro (Eryngium foetidum L., Apiaceae) is a herb native to Tropical America and the West Indies. Although widely used in dishes throughout the Caribbean, Latin America, and the Far East. The herb is reportedly rich in calcium, iron, carotene, and riboflavin and its harvested leaves are widely used as a food flavoring and seasoning herb for meat and many other foods. Their medicinal values include its use as a tea for flu, diabetes, constipation, and fevers. One of its most popular uses is in chutneys as an appetite stimulant. Species of E. foetidum from several countries have shown a variable composition of its essential oil, particularly, in their leaves. Objective: to establish the volatile chemical composition of the essential oil obtained from fresh leaves and
Desarrollo reproductivo del “amancay” Ismene amancaes (Amaryllidaceae) en su ambiente natural Reproductive development of “amancay” Ismene amancaes (Amaryllidaceae) in its natural environment
Mery L. Suni,Edisson Pascual,Enoc Jara
Revista Peruana de Biología , 2012,
Abstract: Ismene amancaes “amancay” es una especie bulbosa característica de las formaciones vegetales denominadas “Lomas” de la costa central del Perú. Emerge al iniciar el periodo de neblina que ocurre en junio, durante el invierno. Presenta flores grandes amarillas y con agradable aroma, muy apreciadas y de valor ornamental. A fin de conocer el desarrollo reproductivo de Ismene amancaes en su ambiente natural se hicieron muestreos mensuales de sus bulbos durante todo un a o. Se realizaron observaciones del interior del bulbo para determinar el inicio de la formación y desarrollo de las yemas florales y se relacionó con la formación de sus hojas y la humedad edáfica. Se puede indicar que las primeras yemas florales se hacen evidentes el a o anterior a su emergencia, en el mes de diciembre, alcanzando el máximo número de yemas florales en febrero (periodo de verano). La diferenciación de las yemas florales se inicia luego de haberse formado las hojas que saldrán el siguiente a o y en el periodo de máximo descenso de la humedad edáfica y de incremento de la temperatura (noviembre). La inflorescencia es la única ramificación que se forma mientras que la yema apical continua formando hojitas. En junio, la peque a inflorescencia alcanza el cuello del bulbo y avanza seguido por las hojas formadas antes de la inflorescencia siendo envolventes a la inflorescencia misma y a la yema foliar apical. La yema foliar continuará su desarrollo y en julio dos de sus hojas salen del bulbo, las siguientes aun peque as quedan dentro y brotarán en el periodo de Lomas del siguiente a o. Se puede se alar que el éxito reproductivo de Ismene amancaes en su etapa inicial es dependiente de los fotoasimilados acumulados como biomasa del bulbo en el periodo de Lomas anterior. Ismene amancaes “amancay” is a bulbose species typical of the central coast vegetation of Peru called “lomas”. This species sprouts in June during the beginning of the winter-fog period. It has large yellow, aromatic flowers valued for their ornamental value. Our goal was to examine the reproductive development of Ismene amancaes in its natural environment, and we recorded monthly observations during a yearlong study. Observations of the interior of the bulbs allowed recording of the beginning of floral bud formation and development, relating them to leaf formation and edaphic humidity. We found that the first floral buds develop the year before their emergence in December, reaching a maximum number of floral buds in February, during the Summer. Floral bud differentiation starts after leaves that will emerge the follow
MONITOREO DE RESIDUOS DE PESTICIDAS ORGANOCLORADOS EN CAMARóN (Penaeus vannamei) DEL áREA COSTERA DE LA BAHíA CARTAGENA (COLOMBIA)
JARAMILLO,BEATRIZ E; MARRUGO,MARíA PATRICIA; DUARTE,EDISSON;
Biotecnología en el Sector Agropecuario y Agroindustrial , 2010,
Abstract: the utilization of organochlorine pesticides for pest control chemical has been of great interest on residue contamination from biológical organisms in the environment. shrimp (penaeus vannamei) samples were monitored as bioindicators for assessment of the water quality in coastal waters along the cartagena bay. twenty-seven samples were collected from 3 sample stations during january, june and november of 2008. the retention times of the extracts of shrimp were compared with standard mix of 20 organochlorine pesticides. gas chromatography equipped with an microelectron capture detector was used as instrumental technique. the aim of this paper was determinate the residual contamination for organochlorine pesticides in shrimp muscle obtained in cartagena's beaches. the limit of detection of all organochlorine pesticides compounds was at the range of o.1-13 ngg-1. the concentration of organochlorine pesticides residues in shrimp was lower than the maximum residue limit for aquatic animals as recommended by the fao.
Establecimiento de un sistema diagnóstico para la detección de Ralstonia solanacearum y diferenciación genética utilizando marcadores moleculares RAPD Establishing a diagnostic system for detecting Ralstonia solanacearum and genetic differentiation using RAPD molecular markers
Chavarro Mesa Edisson,ángel Díaz Jorge Evelio
Revista Colombiana de Biotecnología , 2006,
Abstract: Con el propósito de identificar de manera rápida y precisa el agente causal de la marchitez bacteriana de la papa (Ralstonia solanacearum) en tubérculos asintomáticos, se ha desarrollado una prueba diagnóstica basada en la reacción en cadena de la polimerasa (PCR) utilizando iniciadores específicos para amplificar una región 16S rDNA de 292 pb. Para ello se aisló la bacteria a partir de tubérculos de papa y frutos de plátano, empleando técnicas de cultivo, prueba inmunológica y molecular ELISA-NCM y PCR, respectivamente. En tubérculos asintomáticos la PCR detectó la presencia de R. solanacearum en contraste con la ELISA-NCM que no detectó al patógeno. El análisis de polimorfismos de amplificación al azar de ADN (RAPD) permitió diferenciar y agrupar las procedencias de R. solanacearum por regiones geográficas y razas bacterianas, sugiriendo que existen diferencias entre las colectas de acuerdo con su lugar de origen, indicando alta variabilidad genética. Los resultados mostraron que la PCR es una prueba sensible y específica para la detección de R. solanacearum y por lo tanto puede ser implementada como un método de control del patógeno en programas de producción de semilla y certificación de áreas libres de la enfermedad. Según el origen geográfico de las muestras, el patógeno mostró ser genéticamente heterogéneo, dificultando su control en regiones colombianas con problemas fitosanitarios con R. solanacearum en cultivo de papa. Palabras clave: marchitez bacteriana, moko, PCR-16S ADNr, ELISA-NCM, PCR-RAPD. A polymerase chain reaction-based diagnostic test (PCR) has been developed for amplifying a región and obtaining a 292 bp product by using specific 16S rDNA primers for the rapid and precise identification of the causative agent (Ralstonia solanacearum) of bacterial withering of potato in asymptomatic tubers. The bacteria was isolated from potato tubers and banana fruit using culturing techniques and immunological and molecular ELISA-NCM and PCR tests, respectively. PCR detected the presence of R. solanacearum on asymptomatic tubers by contrast with ELISA-NCM which did not detect this pathogen. Analysing random amplified polymorphic DNA (RAPD) led to differentiating and grouping R. solanacearum by geographical región and bacterial strain, suggesting that differences exist amongst existing collections according to their place of origin, presenting high genetic variability. The results showed that PCR is a sensitive and specific test for detecting R. solanacearum and can therefore be implemented as a method for controlling this pathogen in seed producti
Estudio del efecto de las máscaras de convolución en imágenes mediante el uso de la transformada de Fourier
Forero Vargas Manuel Guillermo,Arias Cruz Edisson Antonio
Ingeniería e Investigación , 2001,
Abstract: Las máscaras de convolución son útiles para extractar información relevante de una imagen. Este artículo presenta una técnica para la evaluación del efecto de estas máscaras a través de la transformada de Fourier, haciendo uso de su propiedad de convolución y su aplicación en la encriptación de imágenes.
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