Combined Myocardial Motion Estimation and Segmentation Using Variational Techniques

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Determinación de los valores de esfuerzos estructurales para vigas de madera perfil Tipo I (Documento II)

Informe final de proyecto de investigación. Código del proyecto: 5402-1401-1008El proyecto tiene como fin determinar los valores de esfuerzo estructural de vigas de madera con perfil tipo I construidas a escala real con tres especies forestales de rápido crecimiento, para ser utilizadas como entre-pisos y techos

Understanding the open circuit voltage in organic solar cells on the basis of a donor-acceptor abrupt (p-n++) heterojunction

By using electrical characterization and classical solid state semiconductor device theory, we demonstrate that the open circuit voltage (V oc ) in organic solar cells based on non-intentional doped semiconductors is fundamentally limited by the built-in potential (V bi ) originated at a donor-acceptor abrupt (p-n ++ ) heterojunction in case of selective contacts. Our analysis is validated using P3HT:PCBM devices fabricated in our research group. We also demonstrate that such a result can be generalized using data already reported in literature for fullerene-based solar cells. Finally, we show that the dependence of V oc on the device contacts can be understood in terms of the potential barriers formed by the Fermi level alignment of semiconductors at the heterojunction and at the Schottky junctions

Global environmental changes: setting priorities for Latin American coastal habitats.

The definitive version is available at www.blackwell-synergy.comThe Intergovernmental Panel for Climate Change (IPCC) reports that Global Environmental Changes (GEC) are occurring quicker than at any other time over the last 25 million years and impacting upon marine environments (Bellard et al., 2012). There is overwhelming evidence showing that GEC are affecting both the quality and quantity of the goods and services provided by a wide range of marine ecosystems. In order to discuss regional preparedness for global environmental changes, a workshop was held in Ilhabela, Brazil (22- 26 April 2012) entitled "Evaluating the Sensitivity of Central and South American Benthic Communities to Global Environmental Changes" that drew together scientists from ten Latin American and three European countries. © 2013 Blackwell Publishing Ltd

Construction of anti-de Sitter-like spacetimes using the metric conformal Einstein field equations: the vacuum case

We make use of the metric version of the conformal Einstein field equations to construct anti-de Sitter-like spacetimes by means of a suitably posed initial-boundary value problem. The evolution system associated to this initial-boundary value problem consists of a set of conformal wave equations for a number of conformal fields and the conformal metric. This formulation makes use of generalised wave coordinates and allows the free specification of the Ricci scalar of the conformal metric via a conformal gauge source function. We consider Dirichlet boundary conditions for the evolution equations at the conformal boundary and show that these boundary conditions can, in turn, be constructed from the 3-dimensional Lorentzian metric of the conformal boundary and a linear combination of the incoming and outgoing radiation as measured by certain components of the Weyl tensor. To show that a solution to the conformal evolution equations implies a solution to the Einstein field equations we also provide a discussion of the propagation of the constraints for this initial-boundary value problem. The existence of local solutions to the initial-boundary value problem in a neighbourhood of the corner where the initial hypersurface and the conformal boundary intersect is subject to compatibility conditions between the initial and boundary data. The construction described is amenable to numerical implementation and should allow the systematic exploration of boundary conditions.Comment: 29 pages, 1 figur

The structural basis of Cdc7-Dbf4 kinase dependent targeting and phosphorylation of the MCM2-7 double hexamer

The controlled assembly of replication forks is critical for genome stability. The Dbf4-dependent Cdc7 kinase (DDK) initiates replisome assembly by phosphorylating the MCM2-7 replicative helicase at the N-terminal tails of Mcm2, Mcm4 and Mcm6. At present, it remains poorly understood how DDK docks onto the helicase and how the kinase targets distal Mcm subunits for phosphorylation. Using cryo-electron microscopy and biochemical analysis we discovered that an interaction between the HBRCT domain of Dbf4 with Mcm2 serves as an anchoring point, which supports binding of DDK across the MCM2-7 double-hexamer interface and phosphorylation of Mcm4 on the opposite hexamer. Moreover, a rotation of DDK along its anchoring point allows phosphorylation of Mcm2 and Mcm6. In summary, our work provides fundamental insights into DDK structure, control and selective activation of the MCM2-7 helicase during DNA replication. Importantly, these insights can be exploited for development of novel DDK inhibitors

MEDICIÓN DE LA FUERZA Y POTENCIA MUSCULAR DEL SALTO VERTICAL CON SENTADILLA HACIENDO USO DEL SOFTWARE ANALIZADOR DE VIDEOS TRACKER

En este trabajo se usó el programa analizador de videos Tracker para estudiar el salto vertical con sentadilla realizada por una persona. El salto fue filmado e importado a Tracker donde se construyó el modelo cinemático de salto. A partir del modelo determinamos la altura máxima que alcanza el centro de gravedad del saltador y los valores promedio de fuerza y potencia muscular desarrollados. La simplicidad del método, su bajo costo y la diversidad de variables físicas involucradas hacen que su aplicación sea apropiada no solo en cursos introductorios de física, sino también en pruebas de salto de diferentes disciplinas deportivas.PALABRAS CLAVE: Salto vertical con sentadilla, fuerza y potencia muscular, Tracker.

Meteorological-Based Predictions of Wheat Head Blight Epidemic in the Southern Argentinean Pampas Region

In Argentina, head blight is a highly risky disease (caused by Fusarium graminearum), although its occurrence is sporadic depending on prevalent environmental variables. These traits stimulated the development of predictive models of head blight occurrence which would help growers in the selection of control strategies. Empirical equations for predicting head blight incidence were developed at Pergamino (33° 56′ S, 60° 30′ W) associating temperature and moisture variables with mean disease data. Recently a new fundamental-empirical approach for estimating Fusarium index (incidence% x severity%/100) was developed using data of Pergamino and Marcos Juarez (32° 41′ S, 62°07′ W). In this study our objective was to validate both approaches at three more southern locations: La Dulce (38° 10′ S, 58° 00′ W), Miramar (38° 00′ S, 57° 33′ W) and Balcarce (37° 45′ S, 58° 18W), for the 2001 crop season. Examining partial and mean deviation values between observed and predicted incidence data, an underestimation especially at La Dulce was assessed. A clear improvement of incidence goodness of fit estimations was obtained decreasing the heat accumulation defining the length of the wheat critical period for infection. Employing this last critical period length for the fundamental-empirical approach led to satisfactory Fusarium index predictions. This study showed that both approaches developed at northern locations of the Pampas region can be portable and useful for predicting disease intensity at more southern locations, making only a few changes.Centro de Investigaciones en Fitopatologí

Frequency of Toxoplasma gondii in technologically advanced pig farms and sex as a risk factor

El objetivo del presente estudio fue estimar la frecuencia de cerdos provenientes de crianza tecnificada reactores a toxoplasmosis y la posible asociación del sexo con la positividad a la toxoplasmosis. Se tomaron 240 muestras de sangre de cerdos provenientes de granjas tecnificadas en un camal ubicado en la ciudad de Lima, Perú. Las muestras fueron analizadas mediante el método de inmunofluorescencia indirecta (IFI). La frecuencia de cerdos positivos a toxoplasmosis fue de 21.7%. La evaluación del sexo como posible factor de riesgo arrojó un Odds Ratio (OR) de 1.24 con intervalo de confianza de 0.88-3.06. Se concluye que hay una frecuencia importante de cerdos provenientes de granjas tecnificadas positivos a toxoplasmosis y que el sexo no influye en la presencia de esta enfermedad.The aim of the current study was to estimate the frequency of pigs from technologically advanced farms positive to toxoplasmosis and to evaluate the association between positive reaction and sex of the animal. Blood samples were collected in 240 animals in a slaughterhouse in Lima, Peru. Samples were analyzed by the indirect immunofluorescence assay (IFA). The frequency of pigs positive to toxoplasmosis was 21.7%. Sex as possible risk factor showed an Odds Ratio (OR) of 1.24 with confidence intervals of 0.88-3.06. It was concluded that there is an important frequency of positive pigs to toxoplasmosis and that sex has no influence in the presentation of this disease