1,547 research outputs found

    Formulación del elemento finito serendipito de 20 nodos para la modelización y simulación dinámica de placas y láminas

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    El estudio de las vibraciones de elementos de las estructuras tipo placa y laminas, es un tema de elevado interés en el campo de la ingeniería civil y la aeronáutica. Debido a la dificultad que ofrece la resolución de las ecuaciones que gobiernan este tipo de modelos no lineales de comportamiento, se hace necesaria la utilización de métodos numéricos avanzados y complejos para la obtención de resultados válidos. El Método de los Elementos Finitos (MEF) es muy adecuado para resolver ecuaciones diferenciales o integrales de gran complejidad y cuyas soluciones analíticas no son posibles. Aunque en los últimos años se han publicado una gran número de trabajos que desarrollan y aplican este método de resolución de sistemas mecánicos no lineales, sin embargo a día de hoy sigue siendo un método novedoso en el estudio dinámico de placas y láminas; de hecho, se están investigando nuevos elementos finitos competitivos capaces de resolver este tipo de problemas y que además aprovechen las nuevas prestaciones de los ordenadores actuales

    Asymmetric synthesis of cyclic β-amino carbonyl derivatives by a formal [3 + 2] photocycloaddition

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    Herein, a visible-light mediated strategy unlocking a family of cyclic β-amino carbonyl derivatives bearing three contiguous stereogenic centres is introduced. The overall reactivity relies on the performance of the substrate-catalyst complex to assist both the enantiocontrol and the photoredox tasks. This transformation led to an enantioselective [3 + 2] photocycloaddition between coordinated α,β-unsaturated acyl imidazoles and cyclopropylamine derivative

    Current situation and characterization of the Eurasian wild grapevine in Asturias region (Northwest of the Iberian Peninsula)

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    This work shows the location and study of relic populations of the Eurasian wild grapevine Vitis vinifera ssp. sylvestris (Gmelin) Hegi in the Asturias region (NW of the Iberian Peninsula). The comprehensive study includes the description of their habitats, of the main botanical supporters of these lianas and of the parasitic species causing them biological stress, the ampelographic description of the populations, wine elaboration from bunches of female vines and a genetic study based on 240 nuclear SNP data. The results obtained have allowed to verify the abundance of this genetic resource in the eastern and central areas of the region. The species that support this liana were different depending on the position (alluvial, colluvial or coastal) of the populations. Several ampelographic differences have been confirmed between male and female individuals. The erineum strain of Colomerus vitis (Pagenstecher) (Acari, Eryophidae) and mildews were the most frequent parasitic species found in the populations. Berries presented a low sugar content, and wines a low alcoholic content and a high total polyphenol index and colour intensity. Feral Vitaceae were found accompanying some of the sylvestris populations mainly in riverbanks and colluvial positions. The genetic study showed a clear distinction of the sylvestris vines from the most common grape varieties in the region, even though one of the sylvestris has a compatible parent-offspring relationship with the variety ‘Camaraou Noir’. The progressive reduction of this subspecies as a consequence of the human activities, plagues and diseases highlights the importance of regulating its conservation in order to avoid its extinction

    Granular cell tumor : report of 8 intraoral cases

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    Granular cell tumor (GCT) is an uncommon neoplasm of controversial origin that can appear in any corporal localization, including the orofacial region. Although aggressive and malignant variants of this neoplasm have been described, most of GCTs are benign. In spite of the amount of research, the etiology of this neoplasm remains unclear and its histogenesis and its possible muscular, conective or neural origin has been broadly debated. In this paper 8 oral cases are presented, corresponding to 5 women and 3 men, with a mean age of 36.1 years old and a mean time of evolution of the lesions of 8.3 months. The most common localization was the tongue (75%). In all the cases a resection with safety margins of the lesions was carried out under local anesthesia. The samples were fixed and processed for histopathological study. The main clinicopathologic and diagnostic features of this neoplasm are reviewed and discussed

    Prospective associations between a priori dietary patterns adherence and kidney function in an elderly Mediterranean population at high cardiovascular risk

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    Purpose To assess the association between three diferent a priori dietary patterns adherence (17-item energy reduced Mediterranean Diet (MedDiet), Trichopoulou-MedDiet and Dietary Approach to Stop Hypertension (DASH)), as well as the Protein Diet Score and kidney function decline after one year of follow-up in elderly individuals with overweight/obesity and metabolic syndrome (MetS). Methods We prospectively analyzed 5675 participants (55–75 years) from the PREDIMED-Plus study. At baseline and at one year, we evaluated the creatinine-based estimated glomerular fltration rate (eGFR) and food-frequency questionnaires derived dietary scores. Associations between four categories (decrease/maintenance and tertiles of increase) of each dietary pattern and changes in eGFR (ml/min/1.73m2 ) or≥10% eGFR decline were assessed by ftting multivariable linear or logistic regression models, as appropriate. Results Participants in the highest tertile of increase in 17-item erMedDiet Score showed higher upward changes in eGFR (β: 1.87 ml/min/1.73m2 ; 95% CI: 1.00–2.73) and had lower odds of≥10% eGFR decline (OR: 0.62; 95% CI: 0.47–0.82) compared to individuals in the decrease/maintenance category, while Trichopoulou-MedDiet and DASH Scores were not associated with any renal outcomes. Those in the highest tertile of increase in Protein Diet Score had greater downward changes in eGFR (β: − 0.87 ml/min/1.73m2 ; 95% CI: − 1.73 to − 0.01) and 32% higher odds of eGFR decline (OR: 1.32; 95% CI: 1.00–1.75). Conclusions Among elderly individuals with overweight/obesity and MetS, only higher upward change in the 17-item erMedDiet score adherence was associated with better kidney function after one year. However, increasing Protein Diet Score appeared to have an adverse impact on kidney health. Trial Registration Number: ISRCTN89898870 (Data of registration: 2014)

    Identificación de poblaciones de vid silvestre y parras guiadas sobre las fachadas de los caseríos de la Cuadrilla de Ayala (Álava, España).

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    El presente trabajo se ha centrado sobre la Cuadrilla de Ayala (Álava), donde se han localizado ocho poblaciones relictas de vid silvestre en diversos hábitats. Se ha comprobado su carácter dioico durante el periodo de floración. Se han identificado las principales especies parásitas existentes sobre estas parras y las principales componentes de su vegetación acompañante. Por otro lado, se han estudiado quince vides cultivadas, con una edad superior a cincuenta años, situadas en la fachada principal de los caseríos. El análisis del ADN de ambos tipos de parras se ha realizado con 48 marcadores SNPs. Los resultados obtenidos han sido comparados con la base de datos disponible en el Instituto de Ciencias de la Vid y del Vino (Logroño), a fin de proceder a la caracterización genética de las muestras

    Identifying populations of wild vines and grapevines trained on the facades of old farmhouses.

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    El presente trabajo se ha centrado sobre la Cuadrilla de Ayala (Álava), donde se han localizado ocho poblaciones relictas de vid silvestre en diversos hábitats. Se ha comprobado su carácter dioico durante el periodo de floración. Se han identificado las principales especies parásitas existentes sobre estas parras y las principales componentes de su vegetación acompañante. Por otro lado, se han estudiado quince vides cultivadas, con una edad superior a cincuenta años, situadas en la fachada principal de los caseríos. El análisis del ADN de ambos tipos de parras se ha realizado con 48 marcadores SNPs. Los resultados obtenidos han sido comparados con la base de datos disponible en el Instituto de Ciencias de la Vid y del Vino (Logroño), a fin de proceder a la caracterización genética de las muestras.This paper focuses on the Cuadrilla de Ayala (Álava province, Spain), where eight relic wild grapevine populations were located in different habitats. The dioecious nature of these lianas was determined at flowering time. The main parasitic species on these vines and also the most frequent taxa of their accompanying vegetation were identified. On the other hand, fifteen vines, aged in excess of fifty, and located in the main entrances of traditional farmhouses (caseríos), were also studied. The analysis of the DNA from both kinds of sampled vines was based on 48 SNPs markers. Results were compared with the available data base at the Instituto de Ciencias de la Vid y del Vino (Logroño, Spain) for the sample genetic characterization

    Development of an activity disease score in patients with uveitis (UVEDAI)

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    To develop a disease activity index for patients with uveitis (UVEDAI) encompassing the relevant domains of disease activity considered important among experts in this field. The steps for designing UVEDAI were: (a) Defining the construct and establishing the domains through a formal judgment of experts, (b) A two-round Delphi study with a panel of 15 experts to determine the relevant items, (c) Selection of items: A logistic regression model was developed that set ocular inflammatory activity as the dependent variable. The construct "uveitis inflammatory activity" was defined as any intraocular inflammation that included external structures (cornea) in addition to uvea. Seven domains and 15 items were identified: best-corrected visual acuity, inflammation of the anterior chamber (anterior chamber cells, hypopyon, the presence of fibrin, active posterior keratic precipitates and iris nodules), intraocular pressure, inflammation of the vitreous cavity (vitreous haze, snowballs and snowbanks), central macular edema, inflammation of the posterior pole (the presence and number of choroidal/retinal lesions, vascular inflammation and papillitis), and global assessment from both (patient and physician). From all the variables studied in the multivariate model, anterior chamber cell grade, vitreous haze, central macular edema, inflammatory vessel sheathing, papillitis, choroidal/retinal lesions and patient evaluation were included in UVEDAI. UVEDAI is an index designed to assess the global ocular inflammatory activity in patients with uveitis. It might prove worthwhile to motorize the activity of this extraarticular manifestation of some rheumatic diseases
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