Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 62 )

2018 ( 107 )

2017 ( 114 )

2016 ( 162 )

Custom range...

Search Results: 1 - 10 of 75092 matches for " Jorge Alberto;Amador-Ramírez "
All listed articles are free for downloading (OA Articles)
Page 1 /75092
Display every page Item
Efecto del riego suplementario en la producción de biomasa y grano de frijol de temporal en Zacatecas, México
Acosta-Díaz, Efraín;Acosta-Gallegos, Jorge Alberto;Amador-Ramírez, Mario Domingo;Padilla-Ramírez, José Saúl;
Agricultura técnica en México , 2009,
Abstract: in the semiarid highlands of north-central mexico, the lack of water for agricultural production is an important problem, particularly since annually a depletion of two m in the water mirror of local wells is taking place and the water storage capacity in dams is limited. because of the above situation, the optimization of water resources through supplemental irrigation in critical stages of bean sown under rainfed conditions is important. the aim of the present research was to determine the effect of supplemental irrigation on shoot biomass accumulation and seed yield in two sets of improved cultivars with different seed type. two experiments were established at cezac experiment station in zacatecas, mexico in 2001; nine black-seeded cultivars were evaluated in one trial, and 14 seed colored cultivars in a second one. all cultivars are of the type iii indeterminate growth habit. two soil moisture levels were utilized: 1) rainfall plus supplemental irrigation and 2) natural rainfall conditions. the rainfall plus supplemental irrigation treatment consisted of maintaining the available soil moisture above 50% throughout the crop-growing season, which was achieved by rainfall plus two irrigations, one at pre- and the second at the flowering stages. the natural rainfall treatment depended only on the rainfall occurred during the growing season. in both experiments, average shoot biomass accumulation and seed yield of the rainfall plus supplemental irrigation were significantly higher (p<0.01) than those in the rainfall treatment. in general, black seeded cultivars, that were significantly later to mature (p<0.05), showed higher shoot dry weight and seed yield in response to the treatment rainfed+supplemental irrigation than the colored cultivars. there was a differential response of the cultivars to the moisture treatments; outstanding black seeded cultivars were negro zacatecas, negro ontiveros and negro z524 from the mesoamerican race, while among seed colored cultiva
Adaptation traits in dry bean cultivars grown under drought stress
Acosta-Díaz, Efraín;Acosta-Gallegos, Jorge Alberto;Trejo-López, Carlos;Padilla-Ramírez, José Saúl;Amador-Ramírez, Mario Domingo;
Agricultura técnica en México , 2009,
Abstract: drought is the major constraint to common bean (phaseolus vulgaris l.) production in mexico. the objective of this study was to identify physiological and phenological traits related to drought adaptation in common bean. a field experiment was conducted under a rainout shelter at the valley of mexico experimental station near texcoco, state of mexico. eight common bean cultivars from different genetic races and growth cycle and contrasted drought response were tested under drought stress and non-stress. irrigation was withheld 55 days after sowing at the initiation of flowering, to induce the stressed treatment. starting at this day, six consecutive nondestructive samplings were conducted at noon every other day. in each sampling, leaf water potential, stomata conductance and co2 assimilation rate were determined. data on phenology were also recorded. at physiological maturity, seed yield and shoot biomass were measured. harvest index was calculated. all cultivars exhibited a tendency to escape drought effects throughout accelerated reproductive development. this response was of small magnitude in mesoamerican cultivars negro cotaxtla 91 and bat 477 (type iii) and significant in cultivars from the durango race such as pinto zapata, bayo madero and bayo criollo del llano. significant difference among cultivars for stomata control was observed with high sensitivity in bat 477 and seq 12, cultivars from the mesoamerican race and in ica palmar from nueva granada race. bred and distinct cultivars ica palmar (type i) and pinto villa (type iii) from durango race, displayed high photosynthetic rate and harvest index, traits or mechanisms directly related to seed yield under stress and non-stress conditions.
Presencia de Circulifer tenellus Baker y Beet mild curly top virus en maleza durante el invierno en el centro norte de México Circulifer tenellus Baker and Beet mild curly top virus presence in weeds during the winter in north-central Mexico
Rodolfo Velásquez-Valle,Luis Roberto Reveles-Torres,Mario Domingo Amador-Ramírez,María Mercedes Medina-Aguilar
Revista mexicana de ciencias agrícolas , 2012,
Abstract: Una de las enfermedades más importantes del chile para secado en el norte centro de México es la denominada amarillamientos del chile. Existe poca información acerca de la interacción entre el vector (Circulifer tenellus Baker), el Beet mild curly top virus y la maleza durante el invierno en esta región, consecuentemente el objetivo del trabajo fue identificar maleza de invierno que sirve como refugio para el vector y hospedero del virus en esta región. Entre enero y marzo de 2011 se muestrearon 26 manchones de maleza en los estados de Aguascalientes y Zacatecas. Se capturaron adultos de C. tenellus en 69.2% de los manchones de maleza muestreados; la mayoría (75.5%) de los especímenes eran hembras. El Beet mild curly top fue identificado sólo 15.4% de los sitios de muestreo infectando especies de maleza como Eruca sativa, Reseda sp., Chenopodium sp. y Solanum rostratum L. One of the most important diseases of chili pepper for drying in the north-central Mexico is called yellowing of chili. There is little information about the interaction between the vector (Circulifer tenellus Baker), the Beet mild curly top virus and weeds during the winter in this region; therefore, the objective was to identify winter weeds that serve as are fuge for the vector and host of the virus in this region. Between January and March, 2011, 26 patches of weed were sampled in Aguascalientes and Zacatecas. Adult C. tenellus were captured in 69.2% of the weed sampled patches; most of the specimens were females (75.5%). Beet mild curly top was identified in only 15.4% of the sampling sites, infecting weed species suchas Eruca sativa, Reseda sp., Chenopodium sp. and Solanum rostratum L.
Biomasa y rendimiento de frijol tipo flor de junio bajo riego y sequía
Acosta-Díaz, Efraín;Amador-Ramírez, Mario Domingo;Padilla-Ramírez, José Saúl;Gómez-Delgado, J. Patrocinio;Valadez-Montoya, Heladio;
Agricultura técnica en México , 2007,
Abstract: in the state of zacatecas, mexico 200 thousand ha of dry bean flor de junio class are annually sown, and its yield average is 315 kg ha-1. this low yield is due to intermittent drought during the growing season. the objective was to determine the effect of different soil moisture levels on plant maturity, shoot and root dry weight per plant, root-shoot ratio and yield of four bean genotypes. in 2002, two trials were conducted; one under greenhouse conditions and the other in the field at the unidad de agronomía of the universidad autónoma de zacatecas. in the greenhouse four soil moisture levels in 3 kg pots were evaluated; one without drought and three from moderate to severe stress: a) irrigated (r), 100% of the evapotranspired water was restituted every 12 h during the cycle, b) moderate drought (sm), 75% of the volume of r was restituted, c) severe drought (ss), 50% of the volume of r was restituted and d) moderate drought during the vegetative stage and severe drought during the reproductive stage (smv+ssr). in the field, two treatments were tested: rainfed (s), depending on rainfall and rainfed plus supplemental irrigation (s+r), with rainfall, contribution and three irrigations as needed. the stress treatments affected negatively all traits in the genotypes in comparison with r and s+r treatments in greenhouse and field, respectively. in the greenhouse; in comparison to the control (r) the average reductions observed with the smv+ssr treatment were: seven days to mature, 26% in shoot dry weight, 44% in root dry weight and 53% in yield. the negative effects increased accordingly to the drought level applied, except for root-shoot ratio, which increased with the stress. under field conditions, the average reductions under the rainfed treatment (s) as compared to (s+r) were: 13 days for maturity, 34% in shoot dry weight and 48% in yield. on the basis of yield reduction, drought susceptibility index and geometric mean of yield, lines uaz fj 2 and uaz fj 3 resulte
Efecto de la sequía en la producción de biomasa y grano de frijol
Acosta-Díaz, Efraín;Hernández-Torres, Ismael;Rodríguez-Guerra, Raúl;Pedroza-Flores, Jesús;Amador-Ramírez, Mario D.;Padilla-Ramírez, José Saúl;
Revista mexicana de ciencias agrícolas , 2011,
Abstract: intermittent drought is most limiting factor for bean production (phaseolus vulgaris l.) under seasonal conditions in mexico. aim of this work was to determine drought effect on biomass accumulation of sprout and grain yield in creole and introduced seasonal bean varieties. two experiments were set, one with 21 native varieties and another with 15 introduced varieties, from different uncertain type growth habit, at academic unit la asención from agronomy school of universidad autónoma de nuevo león, mexico in 2009. experiments were done under two treatments of soil humidity: irrigation during whole cycle and drought. in irrigation treatment soil was kept above 60% of serviceable humidity during cultivation cycle, by precipitation and four irrigation aids (two before and other two after flowering), while in treatment of drought irrigation was suspended when flowering started. in both experiments, under drought condition biomass accumulation of sprout and grain yield was significantly lower (p≤ 0.01) than in irrigation treatment. in general, effect of drought treatment on sprout's dry weight was greater in native varieties, while effect on grain yield was greater in introduced varieties. in drought, varieties with higher yield were: native, pinto-2, pinto-1, amarillo mantequilla, boleado, bayo blanco, canelo and quipincillo rojo-1; and introduced, peruano, flor de mayo media oreja, pinto-5 and ojo de cabra. in accordance with drought susceptibility index and geometric average, most efficient varieties for production of grain yield under both humidity conditions were: pinto-2, amarillo mantequilla, pinto-1, boleado, peruano, flor de mayo media oreja, pinto-5 and ojo de cabra; without exception, all these varieties were collected in test region, which demonstrates importance of local adaptation under drought conditions.
Relación entre índice de área foliar y rendimiento en frijol bajo condiciones de secano
Acosta Díaz, Efraín;Acosta Gallegos, Jorge Alberto;Amador Ramírez, Mario Domingo;Padilla Ramírez, José Saúl;
Agricultura técnica en México , 2008,
Abstract: the leaves of the bean plant are one of the organs more affected by intermittent drought stress. the objective of this research was to determine the relationship between the leaf area index and seed yield at four phenological stages in dry bean cultivars of different grain type grown under rainfed conditions. the study was conducted in the main three producing areas in the state of zacatecas, mexico, during the summer of 2002 at six locations: four in the northwestern area, sown with a cv. negro san luis type; one in the central region, with a cv. of the flor de junio type and one in the southeastern region, with a cv. of the flor de mayo type. in each location, eight fields were chosen and in each two rows of 5 m longitude with four replications. four leaf area index samplings were made at four phenological stages: at the beginning of flowering, beginning of pod formation, beginning seed filling, and intermediate seed filling. seed yield was determined at physiological maturity. the relationship between the leaf area index at different stages and seed yield was determined by simple correlations. in general, average leaf area index increased with the development of the phenological stages, the highest values were observed at the beginning of the seed filling stage. average seed yield varied among locations: 130 g m-2 at the northwestern region with cv. negro san luis type, 139 g m-2 at central with cv. flor de junio type and 95 g m-2 at southwestern with cv. flor de mayo type.
Low Dose Total Body Irradiation (600 cGy) as a Conditioning Regimen in Allogenic Hematopoietic Stem Cell Transplant in Children with Acute Lymphoblastic Leukemia  [PDF]
Alberto Olaya-Vargas, Martín Pérez-García, Nideshda Ramírez-Uribe, M. Angeles Del Campo-Martinez, Gerardo Lopez-Hernández, Montserrat Hernández-García, Jorge Amador-Zarco, Guadalupe Garcia-Vega, Yadira Melchor-Vidal, Marta Zapata-Tarres, Rocío Cárdenas-Cardos, Roberto Rivera-Luna
Journal of Cancer Therapy (JCT) , 2016, DOI: 10.4236/jct.2016.78061
Abstract: Total body irradiation (TBI) is conditioning regimen in children with acute lymphoblastic leukemia (ALL) with a very high risk of relapse or in those who have not achieved remission and have relapsed and subsequently received allogenic hematopoietic stem cell transplantation (HSCT). A retrospective evaluation of 33 ALL patients in full remission with an indication of HSCT was performed to evaluate overall survival (OS) and event-free survival (EFS). The inclusion criteria included a myeloablative conditioning regimen of TBI at a dose of 600 cGy. The observed OS at 5 years was 50%, and the EFS of 32% we observed difference in the EFS stem cell origin; the peripheral blood (PB) 60%, and the umbilical cord blood (UC) accounted for 40%. Overall, 45% had a documented chimerism. The OS at 5 years from patients with chimeras was 75%, while those without chimeras had an OS at 5 years of 25%. The mortality in the first 100 days was 24%. A total of 24.2% of children presented with acute graft versus-host disease (GVHD), while 33% had chronic GVHD. Currently, there is no general agreement among all international centers regarding the optimum TBI dose. Our study reports an acceptable range of adverse events with a relatively low dose of 600 cGy.
Modelo Hidrodinámico para la Velocidad de un Par de Burbujas Ascendiendo en Línea
Ramírez-Mu?oz,Jorge; Soria,Alberto; Salinas-Rodríguez,Elizabeth;
Información tecnológica , 2007, DOI: 10.4067/S0718-07642007000400010
Abstract: a hydrodynamic analysis on the interaction of two equal-size spherical bubbles aligned on the direction of a uniform, laminar, newtonian and incompressible flow, is presented. the leading bubble is considered as an isolated bubble and the trailing bubble (second bubble) is subjected to four forces: buoyancy, quasisteady drag, fluid impulse and added mass. by applying a force balance on each bubble, an expression for the rising velocity of the trailing bubble was obtained. comparison of this expression with existing experimental data for 3.06, 21.5 and 35.4 reynolds number was performed, obtaining a relative average error between 1.2% and 2.1%. two possible approaches on the trailing bubble drag reduction effect are discussed. it was found that a quasisteady drag is, by itself, unable to incorporate the whole wake effect on the trailing bubble.
20 a?os de Análisis político
Leal Buitrago,Francisco; Restrepo Torres,Jorge Alberto; Ramírez Tobón,William;
Análisis Político , 2008,
Abstract: "análisis político" presents to its readers the reports and articles formulated during the twentieth anniversary of the journal and iepri. the first two texts portray the type of articles published in the journal "análisis político", its contexts and methodologies. the last text present reactions to the perception of the political studies and those of violence in colombia, defending the role carried out by iepri and its publications in that field.
Polimialgia reumática: estudio descriptivo en Medellín, Colombia
Vanegas,Adriana Lucía; Ramírez,Luis Alberto; González,Luis Alonso; Acosta,Jorge Luis;
Revista Colombiana de Reumatología , 2011,
Abstract: background: polymyalgia rheumatic is a syndrome that affects people over 50 years, characterized by pain and stiffness of shoulder and pelvic girdle. its behavior in our population is unknown. it may be a manifestation of rheumatoid arthritis, systemic lupus erythematous, and neoplasm or could be associated with giant cells arteritis and it is a common indication for steroid usage. objective: to analyze clinical, laboratory and treatment features of patients with pmr in medellín between 1998-2011. methodology: descriptive cross-sectional study. we reviewed medical records of patients with pmr with at least 1 follow-up visit. we analyzed social, demographic, clinical, laboratory and therapeutic variables. results: the records of 68 patients were assessed, 79.7% women. pain and stiffness in shoulder and pelvic girdle were major symptoms. 62.3% had erythrocyte sedimentation rate equal to or greater than 40 mm/h and 81.2% had c reactive protein equal to or greater than 0.8 mg/dl. 76.9% received doses of prednisolone of 15 mg/day or below. 95.7% responded within the first 3 months of treatment, 94.2% showed remission (84.6% within the first 6 months), 39.1% relapsed (most within the first year of monitoring). those with elevated esr had a lower response in the first month. five patients developed rheumatoid arthritis and two patients giant cells arteritis. conclusions: these findings add more information about the clinical characteristics of patients with pmr. they allow suggesting early responses to treatment with low to moderate doses of steroids and a lower initial response in patients with elevated esr. design and sample size are insufficient to identify statistically significant associations.
Page 1 /75092
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.