1,515 research outputs found

    The signal of ill-defined CPT weakening entanglement in the BdB_d system

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    In the presence of quantum gravity fluctuations (space-time foam), the CPT operator may be ill-defined. Its perturbative treatment leads to a modification of the Einstein-Podolsky-Rosen correlation of the neutral meson system by adding an Entanglement-weakening term of the wrong exchange symmetry, the ω\omega-effect. In the current paper we identify how to probe the complex ω\omega in the entangled BdB_d-system using Flavour(f)-CP(g) eigenstate decay channels: the connection between the Intensities for the two time-ordered decays (f, g) and (g, f) is lost. Appropriate observables are constructed allowing independent experimental determinations of Re(ω\omega) and Im(ω\omega), disentangled from CPT violation in the evolution Hamiltonian Re(θ\theta) and Im(θ\theta). 2-σ\sigma tensions for both Re(θ\theta) and Im(ω\omega) are shown to be uncorrelated.Comment: 18 pages, 4 figures, 1 tabl

    Study of a hot asphalt mixture response based on energy concepts

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    The main objective of the research reported in this paper is to determine the response of a hot mix asphalt (HMA) in terms of both the tensile strength and energy parameters (based on the assessment of the force-displacement curve) as potential tools for improving the HMA mixture design. The HMAs analyzed were fabricated using a 60-70 penetration asphalt binder, dense-graded aggregate, mineral filler, and different types and contents of mineral filler replacements (i.e., lime, cement, and fly ash). The indirect tensile test was conducted to determine both the HMA tensile strength and force-displacement curve, which allowed for the computation of the HMA toughness as well as the energies involved in the process before and after reaching the tensile strength. Corresponding results suggest that the replacement of mineral filler by cement, lime, and fly ash modified the HMA response in terms of both the tensile strength and energy parameters. In addition, analysis of the energy parameters discussed proved to be useful for determining the optimum mineral filler content of HMA. Consequently, analysis of these energy parameters can benefit the HMA mixture design process. // El objetivo principal de la investigación fue determinar el comportamiento de una mezcla asfáltica en función de la resistencia a la tracción indirecta y parámetros de energía (calculados en función de la curva fuerza-desplazamiento) como herramientas potenciales para mejorar el diseño de mezclas asfálticas. Las mezclas asfálticas analizadas fueron fabricadas con asfalto de penetración 60/70, granulometría cerrada md10 y relleno mineral en diferentes porcentajes y materiales (cal, cemento y ceniza volante). El ensayo de tracción indirecta se utilizó para determinar la resistencia máxima a la tracción y la curva fuerza-desplazamiento, a partir de la cual se calcularon la tenacidad de la mezcla y las energías involucradas en el proceso antes y después de alcanzar la resistencia máxima. Los resultados obtenidos sugieren que reemplazar el relleno mineral por cemento, cal o ceniza volante modifica el comportamiento de la mezcla asfáltica en términos de la resistencia a la tracción y los parámetros de energía. Adicionalmente, el análisis de los parámetros de energía discutidos es útil para establecer el contenido óptimo del relleno mineral. En consecuencia, el análisis de estos parámetros de energía puede beneficiar el proceso de diseño de mezclas asfálticas.Peer ReviewedPostprint (published version

    Effect of filler nature and content on the bituminous mastic behaviour under cyclic loads

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    The role of the filler in asphalt mixtures is particularly important because of its influence on mastic behaviour. The filler improves the resistance properties of bitumen against the action of traffic loads and temperature. However, the filler can also adversely affect bitumen in mastics excessively brittle and stiff due to inappropriate design. For these reasons, it is interesting to investigate the effect of filler type and content on mastic composition. This paper presents results from a strain sweep test applied to bituminous mastics prepared with different filler types and contents at several temperatures. The obtained stiffness modulus and failure strain results provide information to assess the fatigue behaviour of the analysed mastics.Peer ReviewedPostprint (author's final draft

    Gut health in veterinary medicine: A bibliometric analysis of the literature

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    SIMPLE SUMMARY: Gut health has been a main topic in veterinary medicine research after the ban on the use of antimicrobial growth promoters. Gut health has been defined as absence/prevention/avoidance of gastrointestinal disease so that the animal is able to perform its physiological functions. A bibliometric analysis is a set of statistical methods used to explore trends in the scientific literature such as number of publications, most prolific countries and main research areas to highlight publication dynamics and gaps of knowledge. In this case, a bibliometric analysis was performed on veterinary gut health using the database Web of Science and the R package Bibliometrix. A total of 1696 documents were retrieved between 2000 and 2020, showing an increase of 22.4% in the number of annual publications. Pigs (34.8%), poultry (chicken, duck, turkey and quail—33.9%) and aquaculture (fishes, crustaceans and frog—15.0%) were the most studied species while a scarce number of publications was found on felines, cows, horses, rodents, goats and sheep. China (24.7%), USA (17.2%) and Canada (5.7%) were the most productive countries. Three main research lines aimed to explore animal nutrition, prevention of inflammatory diseases and microbiota composition were identified. This study will help drive future research on the topic. ABSTRACT: Gut health is a recent relevant research topic in veterinary medicine and it has been shown to be associated with better zootechnical performances and animal welfare. A bibliometric analysis was performed to explore publication trends, dynamics and possible knowledge gaps in this field in the last twenty years (2000–2020). The database Web of Science was searched and the results were analyzed by the R package Bibliometrix. A total of 1696 documents were retrieved in the evaluated period, showing a constant annual growth in the number of publications of 22.4%. These articles focused mainly on pigs (34.8%), poultry (chicken, duck, turkey and quail—33.9%) and aquaculture (fishes, crustaceans and frog—15.0%) while a scarce number was found on felines, cows, horses, rodents, goats and sheep. China was the most productive country (24.7%) followed by the USA (17.2%) and Canada (5.7%). Keyword’s analysis showed that the main research lines aimed to explore animal nutrition, prevention of inflammatory diseases and microbiota composition. This study shows a comprehensive bibliometric analysis of the evolution of veterinary gut health research that will help to drive future investigations on this topic

    The Arabidopsis Synaptotagmin1 is enriched in endoplasmic reticulum-plasma membrane contact sites and confers cellular resistance to mechanical stresses

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    Eukaryotic endoplasmic reticulum (ER)-plasma membrane (PM) contact sites are evolutionarily conserved microdomains that have important roles in specialized metabolic functions such as ER-PM communication, lipid homeostasis, and Ca2+ influx. Despite recent advances in knowledge about ER-PM contact site components and functions in yeast (Saccharomyces cerevisiae) and mammals, relatively little is known about the functional significance of these structures in plants. In this report, we characterize the Arabidopsis (Arabidopsis thaliana) phospholipid binding Synaptotagmin1 (SYT1) as a plant ortholog of the mammal extended synaptotagmins and yeast tricalbins families of ER-PM anchors. We propose that SYT1 functions at ER-PM contact sites because it displays a dual ER-PM localization, it is enriched in microtubule-depleted regions at the cell cortex, and it colocalizes with Vesicle-Associated Protein27-1, a known ER-PM marker. Furthermore, biochemical and physiological analyses indicate that SYT1 might function as an electrostatic phospholipid anchor conferring mechanical stability in plant cells. Together, the subcellular localization and functional characterization of SYT1 highlights a putative role of plant ER-PM contact site components in the cellular adaptation to environmental stresses

    A Geometric Approach Towards Momentum Conservation

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    In this work, a geometric discretization of the Navier-Stokes equations is sought by treating momentum as a covector-valued volume-form. The novelty of this approach is that we treat conservation of momentum as a tensor equation and describe a higher order approximation to this tensor equation. The resulting scheme satisfies mass and momentum conservation laws exactly, and resembles a staggered-mesh finite-volume method. Numerical test-cases to which the discretization scheme is applied are the Kovasznay flow, and lid-driven cavity flow

    Fine Grid Numerical Solutions of Triangular Cavity Flow

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    Numerical solutions of 2-D steady incompressible flow inside a triangular cavity are presented. For the purpose of comparing our results with several different triangular cavity studies with different triangle geometries, a general triangle mapped onto a computational domain is considered. The Navier-Stokes equations in general curvilinear coordinates in streamfunction and vorticity formulation are numerically solved. Using a very fine grid mesh, the triangular cavity flow is solved for high Reynolds numbers. The results are compared with the numerical solutions found in the literature and also with analytical solutions as well. Detailed results are presented

    Titanato de circonio: estabilidad termodinámica y expansión térmica

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    El titanato de circonio es un compuesto muy usado en aplicaciones electrocerámicas, aunque también se han descrito aplicaciones en el campo de la catálisis y de los sensores. Dada la anisotropía en la expansión térmica cristalográfica de este compuesto, podría ser planteado como constituyente de componentes estructurales. En general, para asegurar la integridad estructural y la homogeneidad microestructural de una pieza cerámica, es preciso utilizar velocidades de enfriamiento desde la temperatura de fabricación relativamente bajas. Este requerimiento tiene una importancia fundamental en el titanato de circonio, ya que pequeñas variaciones en la composición y en la velocidad de enfriamiento, producen variaciones significativas tanto en la distribución de fases como en la expansión térmica. En este trabajo se revisan los trabajos existentes sobre la estabilidad del titanato de circonio dentro de los sistemas ZrO2-TiO2 y ZrO2-TiO2-Y2O3. Se describen las principales discrepancias acerca de las fases compatibles existentes en la bibliografía actual y se discute el posible origen de estas discrepancias. Asimismo, se revisan los datos existentes sobre la expansión térmica cristalográfica de este compuesto.Peer reviewe

    Exploration of Possible Quantum Gravity Effects with Neutrinos II: Lorentz Violation in Neutrino Propagation

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    It has been suggested that the interactions of energetic particles with the foamy structure of space-time thought to be generated by quantum-gravitational (QG) effects might violate Lorentz invariance, so that they do not propagate at a universal speed of light. We consider the limits that may be set on a linear or quadratic violation of Lorentz invariance in the propagation of energetic neutrinos, v/c=[1 +- (E/M_\nuQG1)] or [1 +- (E/M_\nu QG2}^2], using data from supernova explosions and the OPERA long-baseline neutrino experiment.Comment: 8 pages, 6 figures, proceedings for invited talk by A.Sakharov at DISCRETE'08, Valencia, Spain; December 200
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