2,993 research outputs found
Effect of pH and nanoclay content on the morphology and physicochemicalproperties of soy protein/montmorillonite nanocomposite obtained byextrusion
The present work attempts to clarify the influence of montmorillonite nanoclay content and pH on the me-chanical properties of extruded soy protein nanocomposites. The mechanical behaviour is dominated by theformation of positive synergies between protein and nanoclay above a nanoclay concentration threshold.Moreover, the presence of nanoclay can improve water uptake. The pH also exerts a strong influence on me-chanical and water absorption properties, although montmorillonite tend to reduce this effect.Eventually, this study put forward the feasibility of using a combination of soy protein and montmorillonite toobtain potentially attractive biodegradable nanocomposite materials, processed by means of a simple and easilyscalable twin-screw extruder.Junta de Andalucía (project TEP-6134)Ministerio de Economía y Competitividad (CTQ2015-71164-P
La construcción social de la imagen del científico de la UNAM en la revista de divulgación de la ciencia ¿Cómo ves?
Las revistas de divulgación científica y tecnológica siguen siendo el medio de comunicación más empleado por los divulgadores para realizar su trabajo. Contrario a lo que se pudiera pensar, la construcción del discurso de divulgación de la ciencia no es simple, ya que es una tarea que demanda el uso de una gran variedad de recursos lingüísticos para su elaboración por lo que es considerado en la actualidad un tipo de lenguaje especial. El presente estudio del discurso revela bajo un enfoque de problematización de tipo semiodiscursivo, la escena discursiva puesta en marcha por el autor en torno a la construcción social de la imagen del científico de la UNAM en la revista de divulgación de la ciencia ¿Cómo ves? Las estrategias discursivas encontradas en el texto de las entrevistas, de la sección fija ¿Quién es?, dan cuenta de las cogniciones sociales o características ideales del buen científico, que son fundamento del sistema ideológico de la ciencia y las cuales son transmitidas a través del discurso de divulgación de la ciencia hacia las personas dentro de un contexto sociocultural determinado
Recurrence relation for relativistic atomic matrix elements
Recurrence formulae for arbitrary hydrogenic radial matrix elements are
obtained in the Dirac form of relativistic quantum mechanics. Our approach is
inspired on the relativistic extension of the second hypervirial method that
has been succesfully employed to deduce an analogous relationship in non
relativistic quantum mechanics. We obtain first the relativistic extension of
the second hypervirial and then the relativistic recurrence relation.
Furthermore, we use such relation to deduce relativistic versions of the
Pasternack-Sternheimer rule and of the virial theorem.Comment: 10 pages, no figure
Development of MRM methods to quantify proteins isoforms of poliphenol oxidase
Comunicaciones a congreso
Una Nueva Política De Recursos Humanos En I+D: El Programa Ramón y Cajal
Publicado en: Economía Industrial, 343 (1): 149-160, 2000Peer reviewe
Relativistic quantum mechanics of a Dirac oscillator
The Dirac oscillator is an exactly soluble model recently introduced in the
context of many particle models in relativistic quantum mechanics. The model
has been also considered as an interaction term for modelling quark confinement
in quantum chromodynamics. These considerations should be enough for
demonstrating that the Dirac oscillator can be an excellent example in
relativistic quantum mechanics. In this paper we offer a solution to the
problem and discuss some of its properties. We also discuss a physical picture
for the Dirac oscillator's non-standard interaction, showing how it arises on
describing the behaviour of a neutral particle carrying an anomalous magnetic
moment and moving inside an uniformly charged sphere.Comment: 19 pages, 1 figur
Relativistically extended Blanchard recurrence relation for hydrogenic matrix elements
General recurrence relations for arbitrary non-diagonal, radial hydrogenic
matrix elements are derived in Dirac relativistic quantum mechanics. Our
approach is based on a generalization of the second hypervirial method
previously employed in the non-relativistic Schr\"odinger case. A relativistic
version of the Pasternack-Sternheimer relation is thence obtained in the
diagonal (i.e. total angular momentum and parity the same) case, from such
relation an expression for the relativistic virial theorem is deduced. To
contribute to the utility of the relations, explicit expressions for the radial
matrix elements of functions of the form and
---where is a Dirac matrix--- are presented.Comment: 21 pages, to be published in J. Phys. B: At. Mol. Opt. Phys. in Apri
Diabetes y su impacto en el territorio periodontal
ResumenDiabetes y enfermedad periodontal corresponden probablemente al mejor ejemplo de cómo una enfermedad sistémica puede tener un efecto en el territorio periodontal. Si bien esta asociación ha sido extensamente estudiada, muchas de las asociaciones propuestas presentan contradicciones. En la presente revisión de la literatura se analizan los siguientes tópicos relevantes para la práctica clínica en periodoncia e implantología: i) Identificación de enfermedad periodontal severa y su capacidad para diagnosticar casos de diabetes; ii) Efectos de la diabetes sobre la enfermedad periodontal; iii) Efectos de la diabetes sobre la reparación periodontal y periimplantaria; iv) Efecto del tratamiento periodontal sobre el control metabólico de la diabetes.AbstractDiabetes and periodontal disease correspond to conditions that probably exemplify how a systemic disease may have a strong impact in the periodontium. Although this association has been studied for several years, many of these studies still show contradictory results. The present review analyses the following questions relevant for the clinician in the fields of periodontology: i) Value of the diagnosis of severe periodontitis and its capacity to identify previously un-diagnosed cases of diabetes; ii) Effects of diabetes on periodontal disease; iii) Effects of diabetes on periodontal and periimplant tissue repair and regeneration and; iv) Effect of periodontal therapy on the metabolic control of diabetes
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