Browsing by Title Facultad de Ciencias
Now showing items 1867-1886 of 8168
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(1985)The decomposition of the title compound (DIMBOA, 1) in aprotic solvents was analysed in terms of linear solvation energy relationships using donor numbers. The results indicate rate-limiting cyclic hemiacetal opening in ...
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(1982)During 4 months from 70 to 79% of the carbon of added glucose, cellulose, and Leuconostoc dextranicus polysaccharide had evolved as CO2 from normal agricultural soils of Chile and California. The presence or additions of ...
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(1982)During 1 yr, CO2-C losses from 7 agricultural soils containing 0.5-1.5% organic C ranged from 70 to 243 mg 100 g - 1 while losses from three allophanic soils containing 4.9-8.9% organic C varied from 92 to 191 mg. Losses ...
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(British Ecological Society, 2014)1. Phylogenetic conservatism of tolerance to freezing temperatures has been cited to explain the tendency of plant lineages to grow in similar climates. However, there is little information about whether or not freezing ...
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(2007)Habitat fragmentation reduces frugivorous bird abundance. Such a reduction may lead to a reduction in seed dispersal, thereby compromising seedling recruitment rate with far reaching consequences for plant population ...
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(Elsevier B.V., 2018)© 2018 Osteosarcoma is a malignant bone tumor that occurs mainly in children and adolescents. Because Wnt signaling has been implicated in the pathogenesis of osteosarcoma, we have investigated the circulating and local ...
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(Elsevier, 2017)A considerable improvement of time constants of tungsten bronze pH sensors was achieved by decreasing the crystal size of the tungsten bronze previously reported by the authors. Experiments have been performed on the basis ...
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(Universidad de Chile, 2008)La cacería de subsistencia y comercial practicada por los habitantes de los bosques Neotropicales disminuye la abundancia de los grandes mamíferos, incluyendo los dasipróctidos. Los dasipróctidos son importantes dispersores ...
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(SOC GENERAL MICROBIOLOGY, 2006-09-14)Altered starch accumulation is a characteristic biochemical symptom of virus infection in plants. To assess its biological importance, infection of Arabidopsis thaliana with Turnip vein-clearing virus, Cucumber mosaic ...
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(Springer-Verlag Berlin Heidelberg, 2013)We consider a simplified model of a nonlinear magnetic metamaterial, consisting of a weakly-coupled, periodic split-ring resonator (SRR) array capable of nonlinear capacitive response. We analyze three related problems: ...
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(Universidad de Chile, 2015)
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(Elsevier, 2020)Forestry plantations of Pinus radiata, managed through clearcutting method, would offer resistance to the movement of native fauna among remnants of native forest. In this study, we evaluate the possibilities of establishing ...
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(AMER CHEMICAL SOC, 2006-07-06)This work deals with exploring some empirical scales of nucleophilicity. We have started evaluating the experimental indices of nucleophilicity proposed by Legon and Millen on the basis of the measure of the force constants ...
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(Kluwer Academic/Plenum Publishers, 1999)The effect of defoliation and consecutive defoliation (condefoliation) of rye seedlings on the allocation patterns of biomass and hydroxamic acids (Hx) was evaluated five days after treatment. Growth of condefoliated ...
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(2006)Intentional cranial deformation is a long lasting and worldwide form of permanent modification of the main human head distinctive anatomical attributes. In northern Chile it was extensively done during five thousand years ...
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(Universidad de Chile, 2024-04)En este trabajo de tesis proponemos una metodología basada en la teoría de grafos y redes complejas para estudiar las propiedades mecánicas y la deformación plástica en vidrios metálicos. Nuestra estrategia se basa en ...
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(2004)Palynologic and stratigraphic data from Laguna Tahui (42°50′S, 73°30′W) indicate cool-temperate and humid conditions there between 14,000 and 10,000 14C yr B.P., followed by warmer and drier-than-present conditions between ...
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(2012)We report pollen, spore, and charcoal records from Lago Augusta (47°05'S, 72°23'W, 440m a.s.l.), a small closed-basin lake located near the modern forest-steppe ecotone east of the Andes in Central Patagonia, Chile. The ...
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(Elsevier, 2012)Much of the ongoing discussion regarding synchrony or bipolar asynchrony of paleoclimate events has centered on the timing and structure of the last glacial termination in the southern mid- latitudes, in particular the ...
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(Universisdad de Chile, 1997)Los compuestos organoclorados existen en la naturaleza principalmente como consecuencia de la actividad agrícola e industrial. Estos compuestos se caracterizan por ser tóxicos y bioacumulables. A pesar de lo anterior, ...