8,759 research outputs found

    A new deep-sea pennatulacean (Anthozoa: Octocorallia: Chunellidae) from the Porcupine Abyssal Plain (NE Atlantic)

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    During the BENGAL cruises, an important collection of deep-sea benthic organisms was sampled. Among the pennatulacean colonies, a previously undescribed species of chunellid was collected. That material is here described as the type species of a new genus, Porcupinella gen. nov. The new genus and species are described based on material collected in the Porcupine Abyssal Plain (NE Atlantic), 4,839–4,847 m in depth. This is the first time that a chunellid is reported from the Atlantic Ocean. The new genus is compared with the other genera in the family, and some phylogenetic remarks about the families Chunellidae and Umbellulidae are also provided

    Biomechanical analysis of a cranial Patient Specific Implant on the interface with the bone using the Finite Element Method

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    - New advance technologies based on reverse engineering , design and additive manufacturing, have expanded design capabilities for biomedical applications to include Patient Specific Implants (PSI). This change in design paradigms needs advanced tools to assess the mechanical performance of the product, and simulate the impact on the patient. In this work, we perform a structural analysis on the interface of a cranial PSI under static loading conditions. Based on those simulations, we have identified the regions with high stress and strain and checked the failure criteria both in the implant and the skull. We evaluate the quality of the design of the implant and determine their response given different materials, in order to ensure optimality of the final product to be manufactured

    ¿Se pueden conseguir plásticos barrera a medida?

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    La Industria del Envase y Embalaje forma parte de uno de los sectores principales de aplicación de los materiales polímeros. De todos es conocido que el vidrio, papel y metales que durante muchos años se utilizaron en el embalaje y empaquetamiento de alimentos, bebidas y otros productos han sido parcialmente reemplazados en la actualidad, por sustancias de naturaleza polimérica que permiten la regularización del transporte de gases y vapores a su través. Se puede decir que uno de los principales problemas con los que se encuentran los profesionales del Sector es encontrar la mejor protección de los productos desde su empaquetamiento hasta su utilización final por el consumidor. La preservación de la calidad de los productos envasados involucra no solo la protección del sabor sino también la necesidad de evitar malos olores en el alimento envasado. De ahí la importancia que el análisis de las propiedades de transporte de masas en los filmes tiene en la industria del envasado. Sin embargo los estudios del transporte de gases y/o vapores son complejos ya que la permeabilidad del material es el resultado de diferentes etapas, por un lado la solubilidad del gas en una cara de la membrana y por otro su difusión en el interior del film hacia la otra cara y su desorción de la misma. Todas estas etapas están fuertemente influenciadas por una serie de factores, como la naturaleza del film polimérico, la temperatura de uso, los aditivos (cargas o plastificantes), etc…, que hay que tener en cuenta a la hora de diseñar un material apto para envasado. Por tanto, el objetivo de esta conferencia es revisar los factores que hay que considerar en el transporte de gases a través de membranas poliméricas densas, desde un punto de vista químico-físico, mostrando diversos ejemplos de cómo se pueden modificar estas propiedades barrera para adecuarlas a las necesidades del producto a envasar.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Genetic study in patients operated dentally and anesthetized with articaine-epinephrine

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    Aims: In this study we wanted to figure out if there was a correlation between OPRM1 N40D, TRPV1 I316M, TRPV1 I585V, NOS3 −786T>C and IL6 −174C>G polymorphisms and the response to locally applied articaine-epinephrine anesthetic. Methods: In this observational study, 114 oral cell samples of patients anesthetized with articaine-epinephrine (54 from men 60 from women), were collected from dental centers in Madrid (Spain). High molecular weight DNA was obtained from oral mucosa cells. The analysis of OPRM1 N40D (rs1799971), TRPV1 I316M (rs222747), TRPV1 I585V (rs8065080) and IL6 −174C>G polymorphism was performed through real-time PCR allelic discrimination using TaqMan probes. Polymorphism NOS3 −786T> C (rs2070744) was analyzed using RFLP-PCR. Results: The studied polymorphisms are involved neither in the response to the anesthetic, nor in the intensity of perceived dental pain. However, in a subset of female patients we found that TRPV1 I316M was associated with a delayed onset of anesthesia. Conclusions: There is no association among these polymorphisms and the time elapsed between the application of the anesthetic and the onset of its effect

    Quasi-exactly Solvable Lie Superalgebras of Differential Operators

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    In this paper, we study Lie superalgebras of 2×22\times 2 matrix-valued first-order differential operators on the complex line. We first completely classify all such superalgebras of finite dimension. Among the finite-dimensional superalgebras whose odd subspace is nontrivial, we find those admitting a finite-dimensional invariant module of smooth vector-valued functions, and classify all the resulting finite-dimensional modules. The latter Lie superalgebras and their modules are the building blocks in the construction of QES quantum mechanical models for spin 1/2 particles in one dimension.Comment: LaTeX2e using the amstex and amssymb packages, 24 page

    Nonlinear Pseudo-Supersymmetry in the Framework of N-fold Supersymmetry

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    We recall the importance of recognizing the different mathematical nature of various concepts relating to PT-symmetric quantum theories. After clarifying the relation between supersymmetry and pseudo-supersymmetry, we prove generically that nonlinear pseudo-supersymmetry, recently proposed by Sinha and Roy, is just a special case of N-fold supersymmetry. In particular, we show that all the models constructed by these authors have type A 2-fold supersymmetry. Furthermore, we prove that an arbitrary one-body quantum Hamiltonian which admits two (local) solutions in closed form belongs to type A 2-fold supersymmetry, irrespective of whether or not it is Hermitian, PT-symmetric, pseudo-Hermitian, and so on.Comment: 10 pages, no figures; typos correcte
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