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Search Results: 1 - 10 of 260600 matches for " Hader I; MEJIA G "
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PRODUCCIóN DE ETANOL A PARTIR DE ALMIDóN DE YUCA UTILIZANDO LA ESTRATEGIA DE PROCESO SACARIFICACIóN- FERMENTACIóN SIMULTáNEAS (SSF)
CASTA?O P,Hader I; MEJIA G,Carlos E;
Vitae , 2008,
Abstract: the world trend on fuel management, in special biofuels like ethanol, have gone to explorer new methodologies of process to optimize its production by this reason in this research is about simultaneous sacarification fermentation process and evaluate initial concentration of reducing sugar, and enzyme dosing of spirizyme fuel? are evaluated on productivity and final concentration of ethanol, under ssf (simultaneous saccharification and fermentation) process, from the product of the licuefaction process of cassava starch as substrate. the ssf process is evaluated against shf (independent saccharification and fermentation) process as control. only the factor, initial concentration of substrate presents effect over ethanol productivity. the kinetic of ssf process, in opposite to the shf process, presents time diminution of the global process around 47 y 33% to substrate levels of 150 and 200 g/l respectively. the productivity values are most at a 33% to 150 g/l of reducing sugar, and they keep constant to 200 g/l reducing sugar. the glucose in ssf strategy, at the time it is producing, it is transformed to ethanol, does not allowing to reach superior concentration to 100 g/l of reducing sugar, this implicates there is not substrate inhibition. the ethanol concentration doesn't affect the enzymatic process of sacharification. the ssf process demonstrates his technical viability on the ethanol production, to reduce time an energy requirements on the ethanol production from cassava flour.
PRODUCCIóN DE ETANOL A PARTIR DE ALMIDóN DE YUCA UTILIZANDO LA ESTRATEGIA DE PROCESO SACARIFICACIóN- FERMENTACIóN SIMULTáNEAS (SSF) ETHANOL PRODUCTION FROM CASSAVA STARCH USING THE PROCESS STRATEGY SIMULTANEOUS SACCHARIFICATION-FERMENTATION
Hader I CASTA?O P,Carlos E MEJIA G
Vitae , 2008,
Abstract: La tendencia mundial en el manejo de los combustibles, en especial los biocombustibles como el etanol, ha llevado a explorar nuevas metodologías de proceso para optimizar su producción; por tal razón se aborda en esta investigación el proceso sacarificación fermentación simultáneas, se evalúa la influencia de la concentración de azúcares reductores y la dosificación de la enzima Spirizyme fuel sobre la productividad y concentración final de etanol, bajo el proceso SSF (sacarificación -fermentación simultáneas), partiendo del licuado de almidón de yuca como sustrato. El proceso SSF se compara con un control con características de sacarificación-fermentación independientes (SHF), proceso convencional. Sólo el factor concentración inicial de sustrato presenta efecto sobre la productividad de etanol. Las cinéticas de proceso, frente a las del control, presentan reducciones de tiempo de 47 y 33% para los niveles de sustrato evaluados. Los niveles de productividad son mayores en un 33% para el nivel de 150 g/l de AR (azúcares reductores) y se mantiene constante para 200 g/l. La glucosa en la estrategia SSF, conforme se produce se transforma en etanol, no permitiendo alcanzar concentraciones superiores a 100 g/l, lo que se traduce en que no se presentan inhibiciones por sustrato. La concentración de etanol no afecta la reacción de la enzima en el proceso de sacarificación. El proceso SSF demuestra su viabilidad técnica en la producción de alcohol, al reducir los tiempos y necesidades de energía en la producción de alcohol carburante a partir de almidón de yuca The world trend on fuel management, in special biofuels like ethanol, have gone to explorer new methodologies of process to optimize its production by this reason in this research is about simultaneous sacarification fermentation process and evaluate initial concentration of reducing sugar, and enzyme dosing of Spirizyme fuel are evaluated on productivity and final concentration of ethanol, under SSF (Simultaneous Saccharification and Fermentation) process, from the product of the licuefaction process of cassava starch as substrate. The SSF process is evaluated against SHF (Independent Saccharification and Fermentation) process as control. Only the factor, initial concentration of substrate presents effect over ethanol productivity. The kinetic of SSF process, in opposite to the SHF process, presents time diminution of the global process around 47 y 33% to substrate levels of 150 and 200 g/l respectively. The productivity values are most at a 33% to 150 g/l of reducing sugar, and they keep constant to
ACTIVIDAD BACTERICIDA DEL EXTRACTO ETANóLICO Y DEL ACEITE ESENCIAL DE HOJAS DE Rosmarinus officinalis L. SOBRE ALGUNAS BACTERIAS DE INTERéS ALIMENTARIO
CASTA?O P,Hader I; CIRO G,Gelmy; ZAPATA M,José E; JIMéNEZ R,Silvia L;
Vitae , 2010,
Abstract: this work evaluated the bactericidal activity and determinated the minimum inhibitory concentration (mic) of ethanolic extract and essential oil from rosmarinus officinalis l. leaves on microorganisms of interest in food industry: escherichia coli, staphylococcus aureus, salmonella typhimurium, shigella sonnei, listeria monocytogenes, pseudomonas aeruginosa, bacillus cereus and lactobacillus plantarum. the essential oil showed a broad spectrum of antimicrobial action for both gram positive and gram negative bacteria with mics between 512 - 4096 ppm. the ethanolic extract showed antimicrobial activity against s. sonnei, s. typhimurium and l. monocytogenes with a mic of 1024 ppm. nisin was used as positive control and showed a strong growth inhibition of all bacteria tested with mics between 2 and 1024 ppm. our result shows that preservatives commonly used in the food industry have lower antimicrobial activity than those found in essential oil from r. officinalis l. leaves.
ESTABLECIMIENTO DE SUSPENSIONES CELULARES DE Bixa orellana L. PRODUCTORAS DE COMPUESTOS FENóLICOS POTENCIALMENTE ANTIOFíDICOS CELLULAR SUSPENSIONS ESTABLISHMENT OF Bixa orellana L., PHENOLIC COMPOUNDS PRODUCERS WITH POTENTIAL ANTIOPHIDIC ACTIVITY
Silvia L JIMéNEZ R,Hader I CASTA?O P,Juan Carlos QUINTANA,Gelmy L CIRO G
Vitae , 2008,
Abstract: Se ha desarrollado un protocolo para la producción y masificación de células de achiote en suspensión, a partir de callos friables obtenidos de tejidos de hojas, como estrategia para la obtención de metabolitos antiofídícos, especialmente compuestos fenólicos, y para ello se ha evaluado el efecto de las concentraciones de inóculo, glucosa, fósforo y nitrógeno sobre la cinética de crecimiento celular, en el medio MS+2,4-D (5 ppm)+BAP (1 ppm), almacenados a 25o C, en oscuridad y a 140 rpm, utilizando un dise o factorial completamente aleatorizado de cuatro factores y dos niveles, con evaluación a los 20 y 40 días de establecimiento. El tratamiento que presenta la mayor producción de biomasa de células de achiote en suspensión tiene una concentración inicial de biomasa de 4 g/l, 20 g/l de glucosa, 0.13 g/l de fósforo y 2.52 g/l de nitrógeno. La cinética de crecimiento de las células de achiote en suspensión, en las condiciones de cultivo de este tratamiento, presenta una fase exponencial bien definida de 25 días; a partir de allí se establece una fase estacionaria hasta el tiempo final de la evaluación (40 días). Se comparan los contenidos de fenoles totales entre el material obtenido in vitro y el material vegetal proveniente de plantas crecidas ex-vitro, como criterio válido para justificar posteriores trabajos de producción metabólica in-vitro en esta especie vegetal. A protocol for production and massification of achiote cells in suspension from friable calli of leaf tissues, has been developed as a strategy to obtain antiophidics metabolites, especially phenolics compounds. Concentration effects of, inoculum, glucose, phosphorus and nitrogen, on cellular growth kinetics were evaluated in MS+2,4-D (5 ppm)+BAP (1 ppm) medium, stored at 25o C, darkness and 140 rpm, using a randomized factorial design with 4 factors, two levels and evaluation at 20 and 40 days of establishment. Treatment with highest biomass production of achiote cells in suspension, had an initial biomass concentration of 4g/l, glucose 20g/l, phosphorus 0,13g/l and nitrogen 2,52 g/l. Kinetics growth of achiote cells in suspension in culture conditions, presented a well defined exponential phase of 25 days, since then a stationary phase until the end of the evaluation (40 days). Total phenols contents among material obtained in-vitro and vegetable material obtained ex vitro were compared as a valid criteria to justify later works of in-vitro metabolic production in this vegetable specie.
EVALUACIóN DE ALGUNAS COMBINACIONES DE REGULADORES DE CRECIMIENTO INDUCTORAS DE CALLOS EN ACHIOTE (Bixa orellana L.), PLANTA ACTIVA CONTRA LA MORDEDURA DE SERPIENTES EVALUATION OF SOME GROWTH REGULATORS COMBINATION FOR CALLUS INDUCTION IN ANNATTO (Bixa orellana L.) ACTIVE PLANT AGAINST SNAKE BITES
Juan C. ALARCóN P.,Hader I. CASTA?O P.,Ligia L. CORRALES G.,Silvia L. JIMéNEZ R.
Vitae , 2006,
Abstract: Recientes evidencias sugieren que el achiote puede constituirse en una alternativa terapéutica por sus efectos directos e indirectos contra el veneno de Bothrops asper, serpiente causante de la mayoría de mordeduras en nuestro país. Considerando que la producción metabólica ex vitro de esta planta no se obtiene de manera temprana y que eventualmente puede lograrse con ayuda de cultivos celulares, el trabajo evalúa algunas combinaciones inductoras de callos en segmentos de hojas, raíces y tallos de plantas de Bixa orellana L. con el fin de inducir y masificar tejidos precursores de suspensiones celulares potencialmente productores de los metabolitos activos. Estos explantes, dispuestos en medios nutritivos sin reguladores de crecimiento, o con suplementos de algunas combinaciones de ellos, se almacenan por ocho semanas a 25± 1o C y oscuridad, verificando los porcentajes de formación de callo en las semanas dos, cinco y ocho del cultivo. La generación de callo en explantes provenientes de raíces no resulta masiva, mientras que en tallos y hojas se favorece con el tratamiento empleado y con el tiempo de exposición a los reguladores de crecimiento. Sin importar el explante utilizado, la inducción de callo se aumenta con la exposición al tratamiento que involucra NAA (5 μM) y kinetina (4,64 μM), alcanzando valores de 17.0 % (raíces), 58.9 % (tallos) y 77.5 % (hojas) Recent evidences suggest annatto can be constituted in a therapeutic alternative by its direct and indirect influences against the poison of Bothrops asper, cause of most of snake bite in our country. The ex- vitro metabolic production of this plant is not obtained in early growth stages but it is possible to obtain it by means of cell cultures. This research evaluates some inductive calli combinations of plant segments of Bixa orellana L., like leaves, roots and stems grown in vitro, in order to get high induction rates and bigger amounts of tissue precursors of cellular suspensions, potentially producers of active metabolites. These explants, located in nutritious means without growth regulators, or with supplements of some combinations of them, are stored for eight weeks (25± 1o C and darkness) and the calli formation percentage tested in second, fifth and eighth week of growing. The calli generation in explants from roots is low, whereas in those from stems and leaves is favored with the treatment and with exposition time to the growth regulators. Regardless of the kind of explant used, the calli formation percentage is increased by the treatment that uses NAA (5 μM) and kinetine (4.64 μM), a
ACTIVIDAD BACTERICIDA DEL EXTRACTO ETANóLICO Y DEL ACEITE ESENCIAL DE HOJAS DE Rosmarinus officinalis L. SOBRE ALGUNAS BACTERIAS DE INTERéS ALIMENTARIO BACTERICIDAL ACTIVITY OF ETHANOLIC LEAF EXTRACT AND LEAF ESSENTIAL OIL OF Rosmarinus officinalis L. ON SOME FOODBORNE BACTERIA
Hader I CASTA?O P,Gelmy CIRO G,José E ZAPATA M,Silvia L JIMéNEZ R
Vitae , 2010,
Abstract: En este trabajo se evaluó la actividad bactericida y se determinó la Concentración Inhibitoria Mínima (CIM) del extracto etanólico y del aceite esencial de hojas de Rosmarinus officinalis L. sobre microorganismos de interés alimentario: Escherichia coli, Staphylococcus aureus, Salmonella typhimurium, Shigella sonnei, Listeria monocytogenes, Pseudomonas aeruginosa, Bacillus cereus y Lactobacillus plantarum. El aceite esencial exhibió un amplio espectro de acción antimicrobiana tanto para bacterias Gram positivas como Gram negativas con CIM entre 512 - 4096 ppm. El extracto etanólico mostró actividad antimicrobiana contra las bacterias S. sonnei, S. typhimurium y L. monocytogenes con CIM de 1024 ppm. La nisina, utilizada como control positivo, ocasionó una inhibición del crecimiento de todas las bacterias evaluadas con CIMs entre 2 y 1024 ppm, mientras que los conservantes usados comúnmente en la industria de alimentos presentaron una actividad antimicrobiana menor que la encontrada con el aceite esencial de R. officinalis. This work evaluated the bactericidal activity and determinated the Minimum Inhibitory Concentration (MIC) of ethanolic extract and essential oil from Rosmarinus officinalis L. leaves on microorganisms of interest in food industry: Escherichia coli, Staphylococcus aureus, Salmonella typhimurium, Shigella sonnei, Listeria monocytogenes, Pseudomonas aeruginosa, Bacillus cereus and Lactobacillus plantarum. The essential oil showed a broad spectrum of antimicrobial action for both Gram positive and Gram negative bacteria with MICs between 512 - 4096 ppm. The ethanolic extract showed antimicrobial activity against S. sonnei, S. typhimurium and L. monocytogenes with a MIC of 1024 ppm. Nisin was used as positive control and showed a strong growth inhibition of all bacteria tested with MICs between 2 and 1024 ppm. Our result shows that preservatives commonly used in the food industry have lower antimicrobial activity than those found in essential oil from R. officinalis L. leaves.
ESTABLECIMIENTO DE SUSPENSIONES CELULARES DE Bixa orellana L. PRODUCTORAS DE COMPUESTOS FENóLICOS POTENCIALMENTE ANTIOFíDICOS
JIMéNEZ R,Silvia L; CASTA?O P,Hader I; QUINTANA,Juan Carlos; CIRO G,Gelmy L; QUINCHíA,Lida; ESTRADA,Sebastián;
Vitae , 2008,
Abstract: a protocol for production and massification of achiote cells in suspension from friable calli of leaf tissues, has been developed as a strategy to obtain antiophidics metabolites, especially phenolics compounds. concentration effects of, inoculum, glucose, phosphorus and nitrogen, on cellular growth kinetics were evaluated in ? ms+2,4-d (5 ppm)+bap (1 ppm) medium, stored at 25o c, darkness and 140 rpm, using a randomized factorial design with 4 factors, two levels and evaluation at 20 and 40 days of establishment. treatment with highest biomass production of achiote cells in suspension, had an initial biomass concentration of 4g/l, glucose 20g/l, phosphorus 0,13g/l and nitrogen 2,52 g/l. kinetics growth of achiote cells in suspension in culture conditions, presented a well defined exponential phase of 25 days, since then a stationary phase until the end of the evaluation (40 days). total phenols contents among material obtained in-vitro and vegetable material obtained ex vitro were compared as a valid criteria to justify later works of in-vitro metabolic production in this vegetable specie.
EVALUACIóN DE ALGUNAS COMBINACIONES DE REGULADORES DE CRECIMIENTO INDUCTORAS DE CALLOS EN ACHIOTE (Bixa orellana L.), PLANTA ACTIVA CONTRA LA MORDEDURA DE SERPIENTES
ALARCóN P.,Juan C.; CASTA?O P.,Hader I.; CORRALES G.,Ligia L.; JIMéNEZ R.,Silvia L.; DíAZ C.,Abel;
Vitae , 2006,
Abstract: recent evidences suggest annatto can be constituted in a therapeutic alternative by its direct and indirect influences against the poison of bothrops asper, cause of most of snake bite in our country. the ex- vitro metabolic production of this plant is not obtained in early growth stages but it is possible to obtain it by means of cell cultures. this research evaluates some inductive calli combinations of plant segments of bixa orellana l., like leaves, roots and stems grown in vitro, in order to get high induction rates and bigger amounts of tissue precursors of cellular suspensions, potentially producers of active metabolites. these explants, located in nutritious means without growth regulators, or with supplements of some combinations of them, are stored for eight weeks (25± 1o c and darkness) and the calli formation percentage tested in second, fifth and eighth week of growing. the calli generation in explants from roots is low, whereas in those from stems and leaves is favored with the treatment and with exposition time to the growth regulators. regardless of the kind of explant used, the calli formation percentage is increased by the treatment that uses naa (5 μm) and kinetine (4.64 μm), and showing values of 17,0 %, 58,9 % and 77,5 % for roots, stems and leaves respectively.
Secondary tics and tourettism
Mejia, Nicte I;Jankovic, Joseph;
Revista Brasileira de Psiquiatria , 2005, DOI: 10.1590/S1516-44462005000100006
Abstract: motor and phonic tics are most frequently due to tourette syndrome, but there are many other causes of tics. we analyzed data on 155 patients with tics and co-existent disorders (101m/54f; mean age 40.5 ± 20.2 years). fourteen (9.0%) patients had tics associated with an insult to the basal ganglia, such as head trauma (n = 4, 2.5%), stroke (n = 2, 1.2%), encephalitis (n = 3, 1.9%) and other causes. in addition, certain drugs, toxins, and post-infectious causes were associated with tics. rarely, peripheral injury can cause movement disorders, including tics (n = 1, 0.6%). pervasive developmental disorders, including asperger's syndrome (n = 13, 8.3%), mental retardation (n = 4, 2.5%), autism (n = 3, 1.9%), and savant's syndrome (n = 1, 0.6%), also may be associated with tics, as noted in 21 of the 155 patients (13.5%). genetic and chromosomal disorders, such as down's syndrome 5 (3.2%), neuroacanthocytosis (n = 2, 1.2%), and huntington's disease (n = 1, 0.6%), were associated with tics in 16 patients (10.3%). we have also examined the co-existence of tics and other movement disorders such as dystonia (n = 31, 20.0%) and essential tremor (n = 17, 10.9%). sixteen (10.3%) patients presented psychogenic tics, and one (0.6%) psychogenic tics and dystonia; conversely, tourette syndrome preceded the onset of psychogenic dystonia (n = 1, 0.6%), and psychogenic tremor (n = 1, 0.6%) in two patients. finally, 12 (7.7%) patients had tics in association with non-movement related neurological disorders, such as static encephalopathy (n = 2, 1.2%) and seizures (n = 3, 1.9%). to understand the physiopathology of tics and tourette syndrome, it is important to recognize that these may be caused or associated with other disorders.
Quadrature formulas for the Laplace and Mellin transforms
Rafael G. Campos,Francisco Mejia
Mathematics , 2007,
Abstract: A discrete Laplace transform and its inversion formula are obtained by using a quadrature of the continuous Fourier transform which is given in terms of Hermite polynomials and its zeros. This approach yields a convergent discrete formula for the two-sided Laplace transform if the function to be transformed falls off rapidly to zero and satisfy certain conditions of integrability, achieving convergence also for singular functions. The inversion formula becomes a quadrature formula for the Bromwich integral. This procedure also yields a quadrature formula for the Mellin transform and its corresponding inversion formula that can be generalized straightforwardly for functions of several variables.
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