1,721,026 research outputs found
One Phase vs Two-Phase Modelling of Infiltration Processes
No full textBecause of global warming, the frequency and harmfulness of climate
extrememeteorological events have increased and are expected to increase. Events such as droughts, heatwaves, storms, floodings strongly impact the functioning of critical infrastructure, as well as the stability and degradation of man-made earthworks and natural slopes. The shallower portions of natural soils and earthworks are thus exposed to increasingly severe dry and hot seasons and to intense rainfalls, which affect the depth of the water table and the hydraulic circulation, triggering material degradation and instabilities. Robust modelling of the soil-atmosphere interaction, correctly accounting for unsaturated flow and boundary conditions, is a requirement of modern geotechnical engineering. The assumptions made when modelling infiltration, in terms of infiltration rate, pore and air pressure distribution and evolution, have in fact a relevant impact on model predictions. As a fraction of the pore space of unsaturated soils is occupied by the gas phase, composed of water vapour and dry air, a complete model of infiltration requires accounting for the inflow of the liquid phase and the outflow of the gas phase. Contrarily, infiltration is very often modelled accounting only for the inflow of liquid water. This work explores the consequences and limitations of such simplification by comparing the predictions obtained by adopting both a two-phase and a one-phase model for
the simulation of the infiltration processes
Kinetic study of the stereoselectivity reduction of acetophenone promoted by a strain of Geotrichum spp
Get PDFFil: Decarlini, M. F. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Vázquez, A. M. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Aimar, M. L. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Química. Cátedra de Química Aplicada; Argentina.Nowadays, biocatalytic stereoselective reduction of prochiral ketones is one of the
most important methodologies in organic synthesis for the preparation of chiral
alcohols. These enantiomerically pure alcohols are very important because they
are key precursors in the obtaining of pharmaceutical compounds. Recently, a
screening on fifty six strains of bacteria and fungi was made for our team toidentify
microorganisms capable of performing the stereoselective reduction of
acetophenone (AP) to 1-phenylethanol (1-PE). From this study a strain of
Geotrichum spp.has been isolated and characterized, and this yeast has presented
anexcellent conversion (>99%) and stereoselectivity (>99.9 e.e.%) in the
preparation of (R)-1-PE from AP.Fil: Decarlini, M. F. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Vázquez, A. M. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Aimar, M. L. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Química. Cátedra de Química Aplicada; Argentina.Otras Ciencias Química
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Yeasts as biocatalysts in the stereoselective reduction of acetophnone
Get PDFFil: Decarlini, M. F. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Manzoni, C. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Medici, E. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Vazquez, A. M. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Aimar, M. L. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Química. Cátedra de Química Aplicada; Argentina.The asymmetric reduction of prochiral ketones represents a pivotal transformation for the
production of chiral alcohols. Several of them are considered as key starting materials in obtaining
of pharmaceuticals. Nowadays, bio-reductions are an important component of organic synthesis for
the production of drugs. In this sense, microorganisms are considered an outstanding tool for the
obtaining of these chiral building blocksFil: Decarlini, M. F. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Manzoni, C. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Medici, E. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Vazquez, A. M. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Aimar, M. L. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Química. Cátedra de Química Aplicada; Argentina.Otras Ciencias Química
Bio-reduccion estereoselectiva de acetofenona a (+)-(R)-1-Feniletanol catalizada por especies del genero Candida
Get PDFFil: Decarlini, M. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Aimar, M. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Química. Cátedra de Química Aplicada; Argentina.Fil: Vázquez, A. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Rustán, M. Universidad Nacional de Córdoba; Argentina.Fil: Peralta, N. Universidad Nacional de Córdoba; Argentina.Fil: Mattos, M. Universidad Nacional de Córdoba; Argentina.La reducción estereoselectiva de cetonas proquirales es una de las
reacciones más importantes de la Química Orgánica. Mediante estas transformaciones es
posible la obtención de alcoholes enantioméricamente puros los cuales son precursores
claves en la síntesis de diferentes compuestos de interés farmacéutico. Una de las formas
preferidas de realizar esta transformación es a través de la utilización de procesos
biocatalíticos empleando para ello diversos microorganismos. Estos sistemas biocatalíticos
tienen la ventaja de ser ambientalmente amigables comparados a los métodos clásicos de
síntesis que en general utilizan metales pesados, auxiliares quirales y solventes orgánicos
bajo atmosfera de hidrogeno.http://microbiologia2014.com.ar/website/Fil: Decarlini, M. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Aimar, M. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Química. Cátedra de Química Aplicada; Argentina.Fil: Vázquez, A. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Rustán, M. Universidad Nacional de Córdoba; Argentina.Fil: Peralta, N. Universidad Nacional de Córdoba; Argentina.Fil: Mattos, M. Universidad Nacional de Córdoba; Argentina.Otras Ciencias Química
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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