Inelastic lifetimes of hot electrons in real metals

We report a first-principles description of inelastic lifetimes of excited electrons in real Cu and Al, which we compute, within the GW approximation of many-body theory, from the knowledge of the self-energy of the excited quasiparticle. Our full band-structure calculations indicate that actual lifetimes are the result of a delicate balance between localization, density of states, screening, and Fermi-surface topology. A major contribution from $d$-electrons participating in the screening of electron-electron interactions yields lifetimes of excited electrons in copper that are larger than those of electrons in a free-electron gas with the electron density equal to that of valence ($4s^1$) electrons. In aluminum, a simple metal with no $d$-bands, splitting of the band structure over the Fermi level results in electron lifetimes that are smaller than those of electrons in a free-electron gas.Comment: 4 papes, 2 figures, to appear in Phys. Rev. Let

Risk genes in head and neck cancer: a systematic review and meta-analysis of last 5 years

Head and Neck Carcinoma (HNC), of which the majority are squamous cell carcinomas of the head and neck (SCCHN), is the sixth most prevalent cancers in mankind and, presents high morbidity and low rates of survival.1 It is known that the apoptotic and proliferation genes are involved in cancer development and these could be useful as a biomarker of this pathology. Systematic reviews and meta-analysis allow stronger and more generalized conclusions for identifying some models of risk markers. These models may help in screening, early diagnosis and/or therapy in the clinic.2-5 In recent decades, there has been increased interest in genetic predisposition studies in complex disease. This has led to the production of an enormous number of epidemiologic papers about the relationship between genetic polymorphism and disease. However, the magnitude of association between specific polymorphism and disease is still not established. The identification of a predictive model of risk polymorphisms could help in early diagnosis, and in understanding disease recurrence and/or progression in the subset of patientssubmittedVersio

Non-trace full-F gyro-fluid interchange impurity advection

A full-F isothermal gyro-fluid model and code (which is based on the full distribution function F compared to only small fluctuations) is extended to handle self-consistent coupling of multiple quasi-neutral ion species via the polarisation equation in the long wavelength approximation. The numerical model is used to determine two-dimensional interchange driven ‘blob’ transport in a plasma with intrinsic impurity content for a range of impurity parameters. With the same model, the self-consistent advective interaction of a main plasma species blob with a non-trace impurity cloud is studied. For homogeneous impurity distributions an increased effective mass reduces blob transport, whereas it is found that localised impurity clouds can lead either to acceleration or slowing down of blob propagation depending on the alignment of the impurity density gradient during the acceleration phase of the main ion species blob

Lattice Boltzmann - Langevin simulations of binary mixtures

We report a hybrid numerical method for the solution of the model H fluctuating hydrodynamic equations for binary mixtures. The momentum conservation equations with Landau-Lifshitz stresses are solved using the fluctuating lattice Boltzmann equation while the order parameter conservation equation with Langevin fluxes are solved using the stochastic method of lines. Two methods, based on finite difference and finite volume, are proposed for spatial discretisation of the order parameter equation. Special care is taken to ensure that the fluctuation-dissipation theorem is maintained at the lattice level in both cases. The methods are benchmarked by comparing static and dynamic correlations and excellent agreement is found between analytical and numerical results. The Galilean invariance of the model is tested and found to be satisfactory. Thermally induced capillary fluctuations of the interface are captured accurately, indicating that the model can be used to study nonlinear fluctuations

Resolución de problemas para el aprendizaje significativo de La Biología Celular en la Carrera De Odontología

En la formación del odontólogo generalista, la Biología Celular comprende adquisición de conocimientos necesarios para abordar la problemática de la tríada salud-enfermedad-atención en todos sus aspectos (preventivo, terapéutico y epidemiológico). La enseñanza ?aprendizaje en la que se desarrollan los contenidos de la asignatura se basa en lograr un aprendizaje comprensivo, posibilitando un rol activo por parte del alumno frente a la generación de conocimientos. Para alcanzar el objetivo se propone una metodología de enseñanza ?aprendizaje basada en situaciones problemáticas, relacionadas a la clínica, cuya resolución se fundamenta en aplicar contenidos conceptuales de la Biología Celular, permitiendo la transferencia de los mismos a la Odontología. Para el desarrollo de los contenidos se establecieron tres instancias pedagógicas: clases teóricas, clases teórico-prácticas y clases prácticas con el fin de ir desde lo simple a lo más complejo. Como parte de la propuesta se elaboró además una guía de aprendizaje Desde la implementación de la misma se ha recabado la opinión de los alumnos mediante encuesta al finalizar la asignatura en cada año lectivo, observándose un apoyo positivo en un 80% de alumnadoIn the formation of the general dentist , Cell Biology comprises acquisition of knowledge needed to address the problem of triad health -disease-care (preventive , therapeutic and epidemiological ) at all aspects The teaching and learning in which the contents of the course are developed is based on achieving a comprehensive learning , enabling an active role by the student against the generation of knowledge. To achieve the objective methodology of teaching and learning based on problem situations related to the clinic, whose decision is based on applying conceptual contents of Cell Biology , allowing transfer of the same to Dentistry is proposed. Lectures, practical classes theoretical and practical lessons in order to go from the simple to the more complex: To develop pedagogical content three bodies were established. As part of the proposal also produced a tutorial.Since the implementation of the same has sought the opinion survey of students by the end of the course in each academic year, with positive support by 80 % of studentspublishedVersionFil: Zarate A. M. Universidad Nacional de Córdoba. Facultad de Odontología; Argentina.Fil: Brunotto, Mabel. Universidad Nacional de Córdoba. Facultad de Odontología; Argentina.Fil: Llanes, M. Universidad Nacional de Córdoba. Facultad de Odontología; Argentina.Otras Ciencias de la Educació

Manifestación de la asimetría contractual: el profano frente al experto en la obligación de saneamiento

Al regular la obligación de saneamiento, el Código Civil y Comercial –en adelante, CCC– proyecta una regulación a partir de la distinción experto-profano. Ello se observa, preliminarmente, en varias normas (arts. 1038 inc. b], 1040 útl. párrafo, 1053 inc. b]), las que analizadas en su conjunto permiten advertir una regla de control que impide que el profesional experto se libere de la obligación de saneamiento –y particularmente de la responsabilidad por defectos ocultos– en casos en que, normalmente, podría hacerlo. Resulta conveniente entonces repasar las normas que sostienen nuestra afirmación.Facultad de Ciencias Jurídicas y Sociale

Second messenger/signal transduction pathways in major mood disorders: Moving from membrane to mechanism of action, part II: bipolar disorder

The etiopathogenesis and treatment of major mood disorders have historically focused on modulation of monoaminergic (serotonin, norepinephrine, dopamine) and amino acid [γ-aminobutyric acid (GABA), glutamate] receptors at the plasma membrane. Although the activation and inhibition of these receptors acutely alter local neurotransmitter levels, their neuropsychiatric effects are not immediately observed. This time lag implicates intracellular neuroplasticity as primary in the mechanism of action of antidepressants and mood stabilizers. The modulation of intracellular second messenger/signal transduction cascades affects neurotrophic pathways that are both necessary and sufficient for monoaminergic and amino acid–based treatments. In this review, we will discuss the evidence in support of intracellular mediators in the pathophysiology and treatment of preclinical models of despair and major depressive disorder (MDD). More specifically, we will focus on the following pathways: cAMP/PKA/CREB, neurotrophin-mediated (MAPK and others), p11, Wnt/Fz/Dvl/GSK3β, and NFκB/ΔFosB. We will also discuss recent discoveries with rapidly acting antidepressants, which activate the mammalian target of rapamycin (mTOR) and release of inhibition on local translation via elongation factor stimulation. Throughout this discourse, we will highlight potential intracellular targets for therapeutic intervention. Finally, future clinical implications are discussed

Boltzmann equation and hydrodynamic fluctuations

We apply the method of invariant manifolds to derive equations of generalized hydrodynamics from the linearized Boltzmann equation and determine exact transport coefficients, obeying Green-Kubo formulas. Numerical calculations are performed in the special case of Maxwell molecules. We investigate, through the comparison with experimental data and former approaches, the spectrum of density fluctuations and address the regime of finite Knudsen numbers and finite frequencies hydrodynamics.Comment: This is a more detailed version of a related paper: I.V. Karlin, M. Colangeli, M. Kroger, PRL 100 (2008) 214503, arXiv:0801.2932. It contains comparison between predictions and experiment, in particular. 11 pages, 6 figures, 2 table

Adubação verde no crescimento e na produção de Schinus terebinthifolius, Hibiscus sabdariffa e Jacaranda decurrens.

bitstream/item/68608/1/005-moreira-adubacao.pdfPublicado também no Cadernos de Agroecologia, v. 7, n.2, 2012