oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 61 )

2018 ( 107 )

2017 ( 114 )

2016 ( 162 )

Custom range...

Search Results: 1 - 10 of 75091 matches for " Jorge Alberto;Amador Ramírez "
All listed articles are free for downloading (OA Articles)
Page 1 /75091
Display every page Item
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.
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
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.
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.
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.
Desarrollo larvario de algunas especies del género Bregmaceros (Pisces: Bregmacerotidae) del sureste del Golfo de México
Blas-Cabrera,Jorge; Sánchez-Ramírez,Marina; Oca?a-Luna,Alberto;
Revista de Biología Tropical , 2006,
Abstract: larval development of some bregmaceros species (pisces: bregmacerotidae) from the southeast gulf of mexico. we redescribe the larval development of bregmaceros cantori based on 925 specimens ranging from 1.1 to 20.2 mm in standard length (sl), and describe the larvae of b. atlanticus (27 larvae, 1.7-7.5 mm), b. houdei (six, 1.5-1.9 mm) and b. macclellandi (three, 2.4, 3.4 and 5.4 mm). all specimens were collected in the southern gulf of mexico from november 27 through december 6, 1998. larvae were identified to species, and descriptions were made based on pigmentation, and morphometric and meristic characteristics. we defined five development stages: preflexion, flexion, postflexion, transformation and juvenile. in the preflexion stage b. cantori displayed a greater growth in mouth size and head length relative to sl (positive allometry); there was negative allometry from the flexion to juvenile stage. b. cantori have the shortest body height and head length, thus being the thinnest; whereas b. macclellandi larvae are the most robust ones. from the four species reported from the southern gulf of mexico, b. atlanticus larvae are the most pigmented in both head and body, with an homogeneous pattern; b. macclellandi presents a different pigmentation pattern consisting in large melanophore groups with a body arrangement that changes from one stage to the next; additionally, from the preflexion stage it develops both the occipital radius and pelvic fins. b. houdei larvae measuring 1.5 to 1.9 mm have melanophores at the tip of the lower jaw and the head, as well as at the pectoral fin base. larval development was more pronounced in this b. cantori and b. atlanticus than in specimens from higher latitudes. rev. biol. trop. 54(2): 561-575. epub 2006 jun 01.
Polimialgia reumática: estudio descriptivo en Medellín, Colombia Polymyalgia rheumatica: a descriptive study in Medellin, Colombia
Adriana Lucía Vanegas,Luis Alberto Ramírez,Luis Alonso González,Jorge Luis Acosta
Revista Colombiana de Reumatología , 2011,
Abstract: Introducción: la polimialgia reumática (PMR) es una enfermedad inflamatoria que afecta a mayores de 50 a os, caracterizada por dolor y rigidez en región cervical, cinturas escapular y pélvica y por una rápida respuesta a los glucocorticoides. Hasta donde sabemos, no hay estudios clínicos sobre PMR en nuestra población. Algunas enfermedades reumatológicas de comienzo tardío como artritis reumatoide (AR), lupus eritematoso sistémico (LES), espondiloartropatías y arteritis de células gigantes (ACG) pueden manifestarse con hallazgos de PMR. Igualmente, neoplasias hematológicas y algunos tumores sólidos pueden presentarse con un síndrome polimiálgico. Objetivo: analizar las características clínicas, de laboratorio y terapéuticas de pacientes de Medellín con PMR entre 1998 y 2011. Métodos: estudio descriptivo transversal. Se revisaron historias clínicas de pacientes con PMR y al menos 1 visita de seguimiento. Se analizaron variables sociales, demográficas, clínicas, de laboratorio y terapéuticas. Resultados: se evaluaron sesenta y nueve pacientes (79,7% mujeres), 68 (98,6%) de los cuales tuvieron dolor y/o rigidez en cintura escapular y 62 (89,8%) en cintura pélvica. La velocidad de sedimentación globular (VSG) fue igual o mayor a 40 mm/h en 43 (62,3%) pacientes y la proteína C reactiva (PCR) igual o mayor a 0,8 mg/dl en 56 (81,2%). El 76.9% de los pacientes recibieron prednisolona en dosis = 15 mg/día; 95,7% respondieron en los 3 primeros meses de tratamiento, 94,2% presentaron remisión (84,6% en los 6 primeros meses) y 39,1% tuvieron recaída (77,8% en el primer a o de seguimiento). Los pacientes con VSG elevada tuvieron menor respuesta en el primer mes. Durante el seguimiento, 5 pacientes desarrollaron artritis reumatoide y 2 ACG. Conclusiones: los hallazgos encontrados aportan mayor información sobre las características de los pacientes con PMR en nuestra población y confirman la rápida respuesta al tratamiento con dosis bajas a moderadas de esteroides y menor respuesta inicial en pacientes con VSG elevada. Su dise o y tama o de muestra son insuficientes para definir asociaciones estadísticamente significativas. 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
Desarrollo larvario de algunas especies del género Bregmaceros (Pisces: Bregmacerotidae) del sureste del Golfo de México
Jorge Blas-Cabrera,Marina Sánchez-Ramírez,Alberto Oca?a-Luna
Revista de Biología Tropical , 2006,
Abstract: Se redescribe el desarrollo larvario de Bregmaceros cantori con 925 organismos en tallas de 1.1 a 20.2 mm de longitud patrón (LP) y se describen algunos ejemplares de B. atlanticus (27 larvas de 1.7 a 7.5 mm), de B. houdei (seis organismos de 1.5 a 1.9 mm) y de B. macclellandi (tres larvas de 2.4, 3.4 y 5.4 mm) del sur del Golfo de México (27 noviembre - 6 diciembre 1998). Las larvas se identificaron a nivel específico y se describieron con base en pigmentación, y características morfométricas y merísticas. En la etapa de preflexión B. cantori presentó un mayor crecimiento del tama o de la boca y de la longitud de la cabeza en relación con la longitud patrón (alometría positiva); en cambio de la etapa de flexión a la etapa de juvenil decrecen (alometría negativa). B. cantori es la especie con la menor altura del cuerpo y longitud de la cabeza, siendo así la más delgada. Las larvas de B. macclellandi son las más robustas. De las cuatro especies que se reportan en el sur del Golfo de México, las larvas de B. atlanticus son las que tienen la mayor pigmentación tanto en la cabeza como en el cuerpo, de manera uniforme; los ejemplares de B. macclellandi muestran un patrón de pigmentación diferente: grandes grupos de melanóforos cuya ubicación cambia con la etapa; además ya en la etapa de preflexión tiene desarrollo del radio occipital y las aletas pélvicas. Las larvas de B. houdei con tallas de 1.5 a 1.9 mm tienen melanóforos en la punta de la mandíbula inferior, en la cabez y en la base de las aletas pectorales. Se observó un mayor desarrollo larvario de B. cantori y B. atlanticus que en especímenes de latitudes mayores. Larval development of some Bregmaceros species (Pisces: Bregmacerotidae) from the southeast Gulf of Mexico. We redescribe the larval development of Bregmaceros cantori based on 925 specimens ranging from 1.1 to 20.2 mm in standard length (SL), and describe the larvae of B. atlanticus (27 larvae, 1.7-7.5 mm), B. houdei (six, 1.5-1.9 mm) and B. macclellandi (three, 2.4, 3.4 and 5.4 mm). All specimens were collected in the southern Gulf of Mexico from November 27 through December 6, 1998. Larvae were identified to species, and descriptions were made based on pigmentation, and morphometric and meristic characteristics. We defined five development stages: preflexion, flexion, postflexion, transformation and juvenile. In the preflexion stage B. cantori displayed a greater growth in mouth size and head length relative to SL (positive allometry); there was negative allometry from the flexion to juvenile stage. B. cantori have the shortest body heigh
Page 1 /75091
Display every page Item


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