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Archivos de espa oles en América (Argentina y México)
Carmen Sierra Bárcena
Anuario Americanista Europeo , 2005,
Abstract: El proyecto de recuperación de testimonios documentales de los espa oles republicanos exiliados en diversos países americanos, se comenzó en el a o 1986. Tomando el ejemplo de México y Argentina se describe el proceso de recuperación y localización de los testimonios que estaban en los países que habían acogido a los exiliados espa oles para posteriormente catalogarlos, depositarlos en archivos del estado y difundir On line la información sobre los mismos, para facilitar el acceso universal a la información.
Extranjeros Las dimensiones éticas y políticas de la exclusión.
Bárbara Sierra
Cultura-Hombre-Sociedad , 2006, DOI: 10.7770/cuhso-v12n2-art327
Abstract: .
Potassium and Phosphorus in Muscat Rosada Grape Yield in Elqui Valley Soil
Sierra B,Carlos; Alfaro P,Rubén;
Chilean journal of agricultural research , 2008, DOI: 10.4067/S0718-58392008000300010
Abstract: the effects of p and k on grapevines (vitis vinifera l.) var. muscat rosada were evaluated four years, considering the same levels of n. the experiment was conducted at the vicu?a experimental station (30° s; 70°44′ w) of the instituto de investigaciones agropecuarias (inia). the soil is alluvial antropic miscellaneous (entisols). three fertilization treatments were established: 1) n 160 + p2o5 200 + k2o 300; 2) n 160 + p2o5 0 + k2o 300; and 3) n 160 + p2o5 200 + k2o 0. at the beginning of the experiment, grape vines received all the phosphate fertilizers, 200 kg ha-1 of p2o5 as triple superphosphate in treatments 1 and 3. nitrogen was applied as urea for four years. the applications were initiated when the vine buds measured 20 cm. the k was applied to the soils of treatments 1 and 2, at a dosage of 200 kg ha-1 k2o, using potassium sulphate. between berry set and 30 d before harvest, 100 kg ha-1 k2o were applied as potassium sulphate by fertigation. significant effects of the p fertilization were observed by the second year, with increased cluster numbers per plant. k also increased grape fruit yield by the third year. this response was obtained with less than 5 mg kg-1 of p available in the soil and less than 145 mg kg-1 of exchangeable k in the soil. the initially low content of available k and p suggests a high probability of response to the application of both elements.
Influence of Rootstocks on Nitrogen, Phosphorus and Potassium Content in Petioles of Four Table Grape Varieties
Ibacache G,Antonio; Sierra B,Carlos;
Chilean journal of agricultural research , 2009, DOI: 10.4067/S0718-58392009000400004
Abstract: four field trials were conducted at vicu?a experimental center (30°02' s, 70°44' w) located in the coquimbo region, chile, over four seasons, 2002-2003 to 2005-2006, to determine the influence of 10 rootstocks (freedom, harmony, saint george, salt creek, so4, 1613c, 1103p, 99r, 110r, 140ru, as well as own roots vines) on nutrient content in petioles of vars. flame seedless, thompson seedless, superior seedless and red globe grapevines (vitis vinifera l.). the trials took place at a site that had previously planted to vineyard. the experimental design was randomized complete block with four replicates. petioles opposite to clusters were taken at bloom as samples and analyzed for total n, p and k content. significant differences in nutrient levels due to rootstocks were found in all varieties. rootstocks increased the levels of petiole nutrients (except p) over the values usually reported in literature for table grapes. vines grafted onto the rootstock ?salt creek? had significantly higher petiole n and p content than those on their own roots vines. total n level increased 67% in ?flame seedless?, 77% in ?red globe?, 33% in ?thompson seedless? and 8.5% in ?superior seedless?. on the other hand, the petiole p level doubled in all varieties by using ?salt creek? as rootstock. potassium status was also affected by rootstocks. ?harmony? and ?1613c? showed higher k levels by at least 60% in vars. flame seedless, red globe and thompson seedless as compared to plants grown on their own roots. the present investigation demonstrates that rootstocks may have a considerable effect on grapevine nutrition.
Influence of Rootstocks on Nitrogen, Phosphorus and Potassium Content in Petioles of Four Table Grape Varieties Influencia de Portainjertos sobre el Contenido Peciolar de Nitrógeno, Fósforo y Potasio en Cuatro Variedades de Uva de Mesa
Antonio Ibacache G,Carlos Sierra B
Chilean Journal of Agricultural Research , 2009,
Abstract: Four field trials were conducted at Vicu a Experimental Center (30°02' S, 70°44' W) located in the Coquimbo Region, Chile, over four seasons, 2002-2003 to 2005-2006, to determine the influence of 10 rootstocks (Freedom, Harmony, Saint George, Salt Creek, SO4, 1613C, 1103P, 99R, 110R, 140Ru, as well as own roots vines) on nutrient content in petioles of vars. Flame Seedless, Thompson Seedless, Superior Seedless and Red Globe grapevines (Vitis vinifera L.). The trials took place at a site that had previously planted to vineyard. The experimental design was randomized complete block with four replicates. Petioles opposite to clusters were taken at bloom as samples and analyzed for total N, P and K content. Significant differences in nutrient levels due to rootstocks were found in all varieties. Rootstocks increased the levels of petiole nutrients (except P) over the values usually reported in literature for table grapes. Vines grafted onto the rootstock ‘Salt Creek’ had significantly higher petiole N and P content than those on their own roots vines. Total N level increased 67% in ‘Flame Seedless’, 77% in ‘Red Globe’, 33% in ‘Thompson Seedless’ and 8.5% in ‘Superior Seedless’. On the other hand, the petiole P level doubled in all varieties by using ‘Salt Creek’ as rootstock. Potassium status was also affected by rootstocks. ‘Harmony’ and ‘1613C’ showed higher K levels by at least 60% in vars. Flame Seedless, Red Globe and Thompson Seedless as compared to plants grown on their own roots. The present investigation demonstrates that rootstocks may have a considerable effect on grapevine nutrition. Se realizaron cuatro ensayos en Vicu a (30°02' S, 70°44' O), Región de Coquimbo, Chile, durante cuatro temporadas, 2002-2003 a 2005-2006 para determinar la influencia de 10 portainjertos de vid (Vitis vinifera L.) (Freedom, Harmony, Saint George, Salt Creek, SO4, 1613C, 1103P, 99R, 110R, 140Ru, además de plantas sobre sus propias raíces) sobre el contenido de nutrientes en pecíolos de las vars. Flame Seedless, Thompson Seedless, Superior Seedless y Red Globe. Los ensayos se establecieron en un terreno previamente plantado con vides y el dise o experimental fue de bloques completos al azar con cuatro repeticiones. Se colectaron muestras de pecíolos opuestos al racimo en el estado fenológico de floración, para determinar los contenidos de N total, P y K. En las cuatro variedades se encontraron diferencias significativas en los niveles de nutrientes debido al uso de portainjertos. Los portainjertos incrementaron los niveles de nutrientes en pecíolos (excepto P) por sob
Potassium and Phosphorus in Muscat Rosada Grape Yield in Elqui Valley Soil Fósforo y Potasio en la Producción de Vid Moscatel Rosada, en Suelo del Valle de Elqui
Carlos Sierra B,Rubén Alfaro P
Chilean Journal of Agricultural Research , 2008,
Abstract: The effects of P and K on grapevines (Vitis vinifera L.) var. Muscat Rosada were evaluated four years, considering the same levels of N. The experiment was conducted at the Vicu a Experimental Station (30° S; 70°44′ W) of the Instituto de Investigaciones Agropecuarias (INIA). The soil is alluvial antropic miscellaneous (Entisols). Three fertilization treatments were established: 1) N 160 + P2O5 200 + K2O 300; 2) N 160 + P2O5 0 + K2O 300; and 3) N 160 + P2O5 200 + K2O 0. At the beginning of the experiment, grape vines received all the phosphate fertilizers, 200 kg ha-1 of P2O5 as triple superphosphate in Treatments 1 and 3. Nitrogen was applied as urea for four years. The applications were initiated when the vine buds measured 20 cm. The K was applied to the soils of Treatments 1 and 2, at a dosage of 200 kg ha-1 K2O, using potassium sulphate. Between berry set and 30 d before harvest, 100 kg ha-1 K2O were applied as potassium sulphate by fertigation. Significant effects of the P fertilization were observed by the second year, with increased cluster numbers per plant. K also increased grape fruit yield by the third year. This response was obtained with less than 5 mg kg-1 of P available in the soil and less than 145 mg kg-1 of exchangeable K in the soil. The initially low content of available K and P suggests a high probability of response to the application of both elements. En el Campo Experimental del Instituto de Investigaciones Agropecuarias (INIA), ubicado en la localidad de Vicu a (30° S; 70°44′ O), se evaluó durante cuatro a os el efecto de la aplicación de P y K, considerando un mismo nivel de aplicación de N en vid (Vitis vinifera L.) var. Moscatel Rosada. El suelo corresponde al tipo misceláneo antrópico coluvial (Entisols). Se establecieron tres tratamientos de fertilización: 1) N 160 + P2O5 200 + K2O 300; 2) N 160 + P2O5 0 + K2O 300; y 3) N 160 + P2O5 200 + K(2)0 0. El parrón recibió toda la fertilización fosfatada aplicada al suelo al inicio del experimento, 200 kg ha-1 P2O5, como superfosfato triple en los Tratamientos 1 y 3. La fertilización nitrogenada se aplicó como urea, durante las cuatro temporadas, y se inició cuando las plantas alcanzaron un largo de brote de 20 cm. El K se aplicó a los Tratamientos 1 y 2 en dosis de 200 unidades de K2O al suelo, usando como fuente sulfato de K, y durante el crecimiento del parrón, desde cuaja y hasta 30 días antes de cosecha, se aplicaron 100 kg ha-1 adicionales de K2O, como sulfato de K vía fertirrigación. Al segundo a o de evaluación se observó un efecto significativo de la fertilización con P,
Bosonic fractional quantum Hall states on the torus from conformal field theory
Anne E. B. Nielsen,Germán Sierra
Statistics , 2013, DOI: 10.1088/1742-5468/2014/04/P04007
Abstract: The Kalmeyer-Laughlin state, which is a lattice version of the bosonic Laughlin state at filling factor one half, has attracted much attention due to its topological and chiral spin liquid properties. Here we show that the Kalmeyer-Laughlin state on the torus can be expressed in terms of a correlator of conformal fields from the $SU(2)_1$ Wess-Zumino-Witten model. This reveals an interesting underlying mathematical structure and provides a natural way to generalize the Kalmeyer-Laughlin state to arbitrary lattices on the torus. We find that the many-body Chern number of the states is unity for more different lattices, which suggests that the topological properties of the states are preserved when the lattice is changed. Finally, we analyze the symmetry properties of the states on square lattices.
Hypoxia mediated isolation and expansion enhances the chondrogenic capacity of bone marrow mesenchymal stromal cells
Adetola B Adesida, Aillette Mulet-Sierra, Nadr M Jomha
Stem Cell Research & Therapy , 2012, DOI: 10.1186/scrt100
Abstract: Freshly harvested human BMSCs were isolated and expanded from the aspirates of six donors, under either hypoxic conditions (3% O2) or normoxic conditions (21% O2). A colony-forming unit fibroblastic (Cfu-f) assay was used to determine the number of cell colonies developed from each donor. BMSCs at passage 2 (P2) were characterized by flow cytometry for the phenotypic expression of cell surface markers on mesenchymal stem cells. BMSCs at P2 were subsequently cultured in vitro as three-dimensional cell pellets in a defined serum-free chondrogenic medium under normoxic and hypoxic conditions. Chondrogenic differentiation of the BMSCs was characterized by biochemical and histological methods and by quantitative gene-expression analysis.After 14 days of culture, the number of BMSC colonies developed under hypoxia was generally higher (8% to 38% depending on donor) than under normoxia. BMSCs were positive for the cell surface markers CD13, CD29, CD44, CD73, CD90, CD105 and CD151, and negative for CD34. Regardless of the oxygen tension during pellet culture, hypoxia-expanded BMSC pellets underwent a more robust chondrogenesis than normoxia-expanded BMSC pellets after three weeks of culture, as judged by increased glycosaminoglycan synthesis and Safranin O staining, along with increased mRNA expression of aggrecan, collagen II and Sox9. Hypoxic conditions enhanced the mRNA expression of hypoxia inducible factor-2 alpha (HIF-2α) but suppressed the mRNA expression of collagen X in BMSC pellet cultures regardless of the oxygen tension during BMSC isolation and propagation.Taken together, our data demonstrate that isolation and expansion of BMSCs under hypoxic conditions augments the chondrogenic potential of BMSCs. This suggests that hypoxia-mediated isolation and expansion of BMSCs may improve clinical applications of BMSCs for cartilage repair.Articular cartilage covers the end of long bones in articulating joints where it provides near frictionless movement. Unfortunately,
Azufre Elemental como Corrector del pH y la Fertilidad de Alfunos Suelos de la III y IV Región de Chile
Sierra B,Carlos; Lancelloti M,Angelus; Vidal P,Iván;
Agricultura Técnica , 2007, DOI: 10.4067/S0365-28072007000200007
Abstract: soils containing calcite are common in northern chile, and this condition decreases the availability of nutrients for plants. the effect of the application of elemental sulphur (s°) was evaluated on soil ph, electrical conductivity and the available micronutrients content in six soils of the iii and iv regions of chile. this was applied in doses of 500 and 1000 mg s° kg-1 and the soils were incubated for periods of 60 and 120 days at 80% of field capacity and 26°c. the experimental design was completely randomized with a factorial design and the treatments included soil, doses of elemental sulphur and times of incubation. the soil characteristics having the greatest influence on acidification by sulphur addition were the caco3, organic matter and sand contents. a highly significant reduction of soil ph occured in those soils with a smaller buffering capacity, as a consequence of lower caco3 and organic matter contents. electrical conductivity increased by the application of elemental sulphur as a result of the rise of soluble salts in the soil. when the ph diminished significantly, the levels of fe, mn and cu micronutrients increased in the soils; mn was the most strongly influenced by the acidification. this information is useful for the application of amendment programs for the calcareous soils of northern chile
Azufre Elemental como Corrector del pH y la Fertilidad de Alfunos Suelos de la III y IV Región de Chile Elemental Sulphur as pH and Soil Fertility Amendment for Some Chileans Soils of Regions III and IV
Carlos Sierra B,Angelus Lancelloti M,Iván Vidal P
Agricultura Técnica , 2007,
Abstract: En los suelos de la zona norte de Chile existen suelos con carbonatos, situación que influye sobre la disponibilidad de nutrientes para los cultivos. En el presente experimento se evaluó en condiciones de laboratorio, el efecto de la aplicación de azufre elemental sobre el pH, conductividad eléctrica y micronutrientes en seis suelos de la III y IV Región, Chile. El azufre se aplicó en dosis de 500 y 1000 mg S° kg-1, y el suelo se incubó por períodos de 60 y 120 días a 80% de su capacidad de campo a 25°C. El experimento se estableció con un dise o de tratamientos completamente al azar con arreglo factorial, donde los factores fueron: suelo, dosis de azufre elemental y tiempo de incubación. Los recipientes en incubación se distribuyeron de acuerdo a un dise o completamente al azar. Las características de los suelos que más influyeron sobre la magnitud del efecto acidificante del azufre elemental fueron los contenidos de CaCO3, materia orgánica y arena. Las reducciones de pH significativas se presentaron en los suelos con una menor capacidad tampón, como consecuencia del menor contenido de CaCO3 y materia orgánica. La conductividad eléctrica se incrementó por la aplicación del azufre elemental, debido al aumento de sales solubles en el suelo. Los niveles de los micronutrientes Fe, Mn y Cu se incrementaron en los suelos cuyos pH disminuyeron significativamente, siendo el Mn el más influenciado por la acidificación. Esta información es de utilidad para establecer programas de aplicación de enmiendas en suelos calcáreos de la zona norte de Chile Soils containing calcite are common in Northern Chile, and this condition decreases the availability of nutrients for plants. The effect of the application of elemental sulphur (S°) was evaluated on soil pH, electrical conductivity and the available micronutrients content in six soils of the III and IV Regions of Chile. This was applied in doses of 500 and 1000 mg S° kg-1 and the soils were incubated for periods of 60 and 120 days at 80% of field capacity and 26°C. The experimental design was completely randomized with a factorial design and the treatments included soil, doses of elemental sulphur and times of incubation. The soil characteristics having the greatest influence on acidification by sulphur addition were the CaCO3, organic matter and sand contents. A highly significant reduction of soil pH occured in those soils with a smaller buffering capacity, as a consequence of lower CaCO3 and organic matter contents. Electrical conductivity increased by the application of elemental sulphur as a result of the rise of
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