537 research outputs found

    Morphology evolution of thermally annealed polycrystalline thin films

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    Investigation of the morphology evolution of annealed polycrystalline Au(111) films by atomic force microscopy and x-ray diffraction leads to a continuous model that correlates such an evolution to local interactions between grains triggering different mechanisms of stress accommodation (grain zipping and shear strain) and relaxation (gap filling and grain rotation). The model takes into consideration findings concerning the in-plane reorientation of the grains during the coalescence to provide a comprehensive picture of the grain-size dependence of the interactions (underlying the origin of the growth stress in polycrystalline systems); and in particular it sheds light on the postcoalescence compressive stress as a consequence of the kinetic limitations for the reorientation of larger surface structuresThis paper was supported by the projects F1-54173 (bilateral program CSIC-Conacyt) 200960I182 (CSIC), and CCG10-UAM/MAT-5537 (DGUI-Comunidad de Madrid and Universidad Aut´onoma deMadrid). A.G.G. acknowledges the financial support of the MICINN Spanish Ministry under the project ESP2006-14282-C02-0

    Biota and geomorphic processes as key environmental factors controlling soil formation at Elephant Point, Maritime Antarctica

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    We examined the main soil forming factors affecting the soil composition, soil properties and the associated soilforming processes at Elephant Point, a small ice-free environment in the South Shetland Islands, Maritime Antarctica. For this purpose, we collected twenty soil samples from each of ten different sites distributed along a linear transect running from the coast to the front of the Rotch Dome glacier. The samples were obtained from surface layers (0–10 cm) and at depth (40–50 cm), although collection was limited in the moraine area by the permafrost table. We determined pH, electrical conductivity, size particle distribution, total organic carbon, total nitrogen and total concentrations of Al, Fe, Ca and P, for physical and chemical characterization of the samples. We also analysed the samples to determine the bioavailability of nutrients and Fe, Al and P partitioning and finally examined them by isotopic (δ15N) and X-ray diffraction (XRD) analysis. The results of the analyses revealed two clear geochemical environments corresponding to the two most extensive geomorphological units in this peninsula: moraine and marine terraces. Soils from the moraine were characterized by alkaline reaction and high quantity of minerals with a low degree of crystallinity, whereas soils from the marine terraces showed acid reaction, high concentration of organometallic complexes and a high diversity of phosphate minerals (taranakite, minyulite, struvite, hydroxylapatite and leucophosphite), which seem to be generated by phosphatization of faecal matter deposited by seabirds and seals. Consequently, biota activity is the most relevant soil differentiating factor in the marine terraces, which add organic matter and activate geochemical cycles. On the other hand, geomorphic processes strongly affected by physical weathering processes such as glacial abrasion (by grinding process), frost shattering, and wind abrasion are the main soil-forming factors in moraine. These forces break up the parent material, transform it and translocate the products formed.info:eu-repo/semantics/publishedVersio

    Pyrolytic characterization of humic acids in relation to carbon sequestration mechanisms in representative soils from the basque country (Northern Spain)

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    Comunicación y póster presentados al citado simposio, celebrado del 17-20 de septiembre, 2002, en Leoben (Austria).Curie-Point analytical pyrolysis was used for the assessment of soil organic matter accumulation processes in representative ecosystems from the Basque Country (Northem Spain). The aim of the study is to identify the main mechanisms of carbon sequestration by carrying out a semiquantitative appraisal of biogeochemical processes ranging from selective preservation of plant macromolecular material to complex processes involving extensive depolymerization of plant-inherited constituents followed by synthesis of humic-type substances.Peer reviewe

    Contribution of critical doses of iprovalicarb, mepanipyrim and tetraconazole to the generation of volatile compounds from Monastrell-based wines

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    Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGThe individual effects of iprovalicarb, mepanipyrim, and tetraconazole on the volatile composition and aromatic profile of Monastrell-based wines were evaluated. To date, no studies about the effect of these fungicides on Monastrell-based wines are available, and the effect on other grape varieties is also unknown. Fungicides were added separately in the cellar to the grape must at two concentration levels (4 and 10 mg/kg for iprovalicarb and mepanipyrim and 1 and 2.5 mg/kg for tetraconazole). The aromatic composition of the final wines was analysed by gas chromatography using flame ionisation and ion trap mass selective detectors. In the presence of fungicides, the most significant variations were observed for isoamyl acetate and 2-phenylethyl acetate (increasing between 20 and 43% compared with the control wine) and ethyl caprate and caprylate (increasing between 12 and 68%). Consequently, treated wines showed a higher global odourant intensity, with increased fresh fruit notes.Ministerio de Economía y Competitividad | Ref. AGL2015-66491-C2-1-RAgencia Estatal de Investigación | Ref. PID2019-105061RB-C2

    Self-determination in teaching formative basketball players and its influence on respect to rules and opponents

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    The aim of this study was to examine adaptive behaviors in teaching formative basketball players with regard to their motivations to play. Hence, 284 federative basketball players, ranging in age from 11 to 16 years old from the Region of Extremadura took part in the study. Descriptive analysis, correlation analysis and lineal regression analysis were conducted with SPSS 19.0 statistical program. Results showed that more self-determined players had greater adaptive conducts, such as respect to rules and opponents. Finally, it is noteworthy to provide intrinsic regulations in youth basketball players to create a good learning and promotes social values

    A rapid and sensitive diagnosis of bovine leukaemia virus infection using the nested shuttle polymerase chain reaction

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    Bovine leukaemia virus (BLV) is the causative agent of enzootic bovine leukosis (EBL). In Argentina, where a program to eradicate EBL has been introduced, sensitive and reliable diagnosis has attained high priority. Although the importance of the agar gel immunodiffusion test remains unchanged for routine work, an additional diagnostic technique is necessary to confirm cases of sera with equivocal results or of calves carrying maternal antibodies. Utilizing a nested shuttle polymerase chain reaction, the proviral DNA was detected from cows experimentally infected with as little as 5 ml of whole blood from BLV seropositive cows that were nonetheless normal in haematological terms. It proved to be a very sensitive technique, since it rapidly revealed the presence of the provirus, frequently at 2 weeks postinoculation and using a two-round procedure of nested PCR taking only 3 hours. Additionally, the primers used flanked a portion of the viral genome often employed to differentiate BLV type applying BamHI digestion. It is concluded that this method might offer a highly promising diagnostic tool for BLV infection.Facultad de Ciencias Veterinaria

    Cystic Fibrosis: actual treatment and future perspectives with nanotechnology

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    Introducción: Actualmente, los tratamientos existentes para tratar la fibrosis quística (FQ) están diseñados para controlar sus síntomas, consistentes principalmente en retención de moco e infección crónica. Se propone la vía pulmonar como alternativa para la administración de los fármacos, principalmente antimicrobianos. Sin embargo, su rápido aclaramiento, que conduce a niveles bajos de fármaco e incremento de los regímenes posológicos, así como la aparición de efectos adversos, hacen de la nanotecnología una estrategia interesante para esta enfermedad. Objetivo: estudiar y analizar los diferentes sistemas nanoparticulares existentes para su uso por vía pulmonar, concretando en el uso de sistemas lipídicos para el tratamiento de la FQ. Método: se realizó una búsqueda no sistemática de artículos en diferentes bases de datos, en los últimos 10 años principalmente, siguiendo pautas establecidas de palabras clave. Resultados: Los progresos que se han conseguido en los últimos años hacen que la FQ pase a ser una enfermedad de adultos. Los tratamientos que se están usando en la actualidad están siendo cada vez más desplazados por otras alternativas, como los sistemas nanoparticulares, siendo idóneos para la administración pulmonar debido a su pequeño tamaño, su liberación sostenida y su elevada biocompatibilidad. Entre éstos, destacan los liposomas por su similitud estructural con el surfactante pulmonar, así como por su capacidad de destruir las biopelículas bacterianas. La mayoría de las formulaciones encontradas contenían un solo fármaco. Conclusión: Existen evidencias científicas que indican que la investigación debe dirigirse hacia el desarrollo de formulaciones que sean capaces de destruir la biopelícula.Introduction: Currently, the management of treatments in cystic fibrosis (CF) is mainly focused to control symptoms, which consist of mucus retention and chronic infection. The pulmonary route is proposed as an interesting alternative for administering drugs, especially antimicrobials. However, the rapid clearance of these, which leads to low drug levels and increased dosage regimens, as well as the appearance of adverse effects, make nanotechnology an interesting strategy for this disease. Objective: to study and analyze the different nanoparticulate systems available for use via the lung, specifying the use of lipid systems for the treatment of CF. Method: a non-systematic search of articles in different databases was carried out, mainly in the last 10 years, following established guidelines for selecting keywords. Results: The progress in recent years makes CF become an adult disease. Current treatments are increasingly being displaced by other alternatives, such as nanoparticular systems, being suitable for pulmonary administration due to their small size, sustained release and high biocompatibility. Among these, liposomes stand out for their structural similarity to lung surfactant, as well as for their ability to destroy bacterial biofilms. Most of the formulations contained a single drug. Conclusion: Scientific literature evidenced that research studies should be directed towards the development of formulations that are intended to destroy the biofilm

    Evaluación del uso apropiado de medicamentos en atención primaria. ¿Cómo se puede mejorar?

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    IntroducciónEl proceso de medicación de un paciente abarca la identificación de su problema de salud, la prescripción para esa indicación por parte del médico, la dispensación farmacéutica y el consumo del fármaco. Los estudios de utilización de medicamentos analizan dicho proceso con el de detectar los factores que alteran el uso correcto de los fármacos.ObjetivoEvaluar la calidad de la prescripción de ciertos medicamentos en atención primaria en función de la indicación para la que fueron prescritos, detectando aquellas características de los pacientes, médicos prescriptores, centros de atención primaria y áreas de salud que influyen en su uso inapropiado.MétodoEstudio prescripción-indicación basado en la estimación de modelos multinivel con bases de datos individualizadas de las prescripciones, que contienen características de las prescripciones, pacientes, médicos, centros de salud y áreas de salud de pertenencia. Estos modelos suponen un avance en este tipo de estudios ya que permiten analizar de forma conjunta la información de distintos niveles y estimar sus respectivas «cuotas de responsabilidad» en la inadecuación de la prescripción.DiscusiónAdemás de su interés metodológico, que puede guiar estudios posteriores, el principal interés del trabajo estriba en su carácter pionero en la utilización masiva de microdatos poblacionales para evaluar la calidad de la prescripción, que proceden de las historias clínicas informatizadas de atención primaria.IntroductionThe process of medicating a patient embraces the identification of the health problem, the doctor’ s prescription to treat this indication, the dispensing of the medicine and its consumption. The studies of use of medicine analyse this process in order to detect those factors that impinge on the correct use of medicines.ObjectiveTo evaluate the quality of the prescription of certain primary care medicines as a function of the indication for which they were prescribed, detecting those features of the patients, prescribing doctors, primary care centre and health district that affect their inappropriate use.MethodPrescription-indication study based on the calculation of multiple-level models with individualised data bases for the prescriptions. These include characteristics of the prescriptions, patients, doctors, health centres and the health district involved. These models are a step forward in this kind of study, in that they enable analysis of the information from different levels at the same time as calculation of the respective «degrees of responsibility» for inadequacies of prescription.DiscussionApart from its methodological originality, which may serve for subsequent studies, the main interest of this study lies in the pioneering nature of its massive use of population micro-data to evaluate prescription quality. These data are taken from the computerised clinical records in primary care
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