940 resultados para Coastal and Estuarine Modeling II


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By reacting 4,4′-bipyridine (bpy) with selected trinuclear triangular CuII complexes, [Cu3(μ3-OH)(μ-pz)3(RCOO)2(LL′)] [pz = pyrazolate anion; R = CH3, CH3CH2, CH2═CH, CH2═C(CH3); L, L′ = Hpz, H2O, MeOH] in MeOH, the substitution of monotopic ligands by ditopic bpy was observed. Depending on the stoichiometric reaction ratios, different compounds were isolated and structurally characterized. One- and two-dimensional coordination polymers (CPs), as well as two hexanuclear CuII clusters were identified. One of the hexanuclear clusters self-assembles into a supramolecular three-dimensional structure, and its crystal packing shows the presence of two intersecting channels, one of which is almost completely occupied by guest bpy, while in the second one guest water molecules are present. This compound also shows a reversible, thermally induced, single-crystal-to-single-crystal transition.

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In this paper, we present a map describing the main geomorphological features of the coastal and marine area between the towns of Albenga and Savona (Ligurian Sea, NW Mediterranean) corresponding to a coastal stretch of ~40 km. To produce this map, we collated data from the literature, orthophotos, perspective photos, multibeam and side scan sonar data, and undertook direct surveys to ground truth data obtained using indirect techniques. We divided the information into nine thematic layers, including bathymetry, natural coastal types, geomorphological elements, seafloor coverage (both geological and biological), coastal and nearshore dynamics, human influence on coastal and marine environments, coastal occupation and protected areas.

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Reconstructing terrestrial water budgets is of prime importance for understanding past climate and environment. To shed more light on how plant-wax derived n-alkanes may be used for this purpose we investigated the distribution and stable isotopic compositions of hydrogen (dD) and carbon (d13C) of plant-wax derived n-C29 and -C31 alkanes in terrestrial, coastal and offshore surface sediments in relation to hydrology along a NW-SE transect east of the Italian Apennines from the Po River to the Eastern Gulf of Taranto. The plant wax average chain length increases southward and may relate to increasing temperature and/or aridity. The plant wax dD of the terrestrial and coastal samples also increases southward and mainly reflects changes in the dD of precipitation. The d13C of plant waxes is primarily interpreted in terms of C3 vegetation changes rather than varying contributions by C4 plants. The plant wax d13C-dD composition of the Po River and Apennine rivers differs considerably from that in southern Italy, and suggests a mainly southern source for plant waxes in marine sediments of the Gulf of Taranto. This calibration provides a basis for the reconstruction of past changes in the Italian water balance and n-alkane source areas.

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Variability in pH is a common occurrence in many aquatic environments, due to physical, chemical and biological processes. In coastal waters, lagoons, estuaries and inland waters, pH can change very rapidly (within seconds or hours) in addition to daily and seasonal changes. At the same time, progressive ocean acidification caused by anthropogenic CO2 emissions is superimposed on these spatial and temporal pH changes. Photosynthetic organisms are therefore unavoidably subject to significant pH variations at the cell surface. Whether this will affect their response to long-term ocean acidification is still unknown, nor is it known whether the short-term sensitivity to pH change is affected by the pCO2 to which the cells are acclimated. We posed the latter open question as our experimental hypothesis: Does acclimation to seawater acidification affect the response of phytoplankton to acute pH variations? The diatom Skeletonema costatum, commonly found in coastal and estuarine waters where short-term acute changes in pH frequently occur, was selected to test the hypothesis. Diatoms were grown at both 390 (pH 8.2, low CO2; LC) and 1000 (pH 7.9, high CO2; HC) µatm CO2 for at least 20 generations, and photosynthetic responses to short-term and acute changes in pH (between 8.2 and 7.6) were investigated. The effective quantum yield of LC-grown cells decreased by ca. 70% only when exposed to pH 7.6; this was not observed when exposed to pH 7.9 or 8.2. HC-grown cells did not show significant responses in any pH treatment. Non-photochemical quenching showed opposite trends. In general, our results indicate that while LC-grown cells are rather sensitive to acidification, HC-grown cells are relatively unresponsive in terms of photochemical performance.

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The present dataset is part of an interdisciplinary project carried out on board the RV Southern Surveyor off New South Wales (Australia) from the 15th to the 31st October 2010. The main objective of the research voyage was to evaluate how the East Australian Current (EAC) affects the optical, chemical, physical, and biological water properties of the continental shelf and slope off the NSW coast.

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The zip folder comprises a text file and a gzipped tar archive. 1) The text file contains individual genotype data for 90 SNPs, 9 microsatellites and the mitochondrial ND4 gene that were determined in deep-sea hydrothermal vent mussels from the Mid-Atlantic Ridge (genus Bathymodiolus). Mussel specimens are grouped according to the population (pop)/location from which they have been sampled (first column). The remaining columns contain the respective allele/haplotype codes for the different genetic loci (names in the header line). The data file is in CONVERT format and can be directly transformed into different input files for population genetic statistics. 2) The tar archive contains NetCDF files with larval dispersal probabilities for simulated annual larval releases between 1998 and 2007. For each simulated vent location (Menez Gwen, Lucky Strike, Rainbow, Vent 1-10) two NetCDF files are given, one for an assumed pelagic larval duration of 1 year and the other one for an assumed pelagic larval duration of 6 months (6m).

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The separation of the lower stage of the ARIANE 5 Vehicle Equipment Bay (VEB) Structure is to be done using a pyrotechnic device. The wave propagation effects produced by the explosion can affect the electronic equipment, so it was decided to analyze, using both physical and numerical modeling, a small piece of the structure to determine the distribution of the accelerations and the relative importance of damping, stiffness, connections, etc. on the response of the equipment.

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Wake effect represents one of the most important aspects to be analyzed at the engineering phase of every wind farm since it supposes an important power deficit and an increase of turbulence levels with the consequent decrease of the lifetime. It depends on the wind farm design, wind turbine type and the atmospheric conditions prevailing at the site. Traditionally industry has used analytical models, quick and robust, which allow carry out at the preliminary stages wind farm engineering in a flexible way. However, new models based on Computational Fluid Dynamics (CFD) are needed. These models must increase the accuracy of the output variables avoiding at the same time an increase in the computational time. Among them, the elliptic models based on the actuator disk technique have reached an extended use during the last years. These models present three important problems in case of being used by default for the solution of large wind farms: the estimation of the reference wind speed upstream of each rotor disk, turbulence modeling and computational time. In order to minimize the consequence of these problems, this PhD Thesis proposes solutions implemented under the open source CFD solver OpenFOAM and adapted for each type of site: a correction on the reference wind speed for the general elliptic models, the semi-parabollic model for large offshore wind farms and the hybrid model for wind farms in complex terrain. All the models are validated in terms of power ratios by means of experimental data derived from real operating wind farms.

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En este proyecto miraremos como los campos de Diseño Participativo de las tecnologías de la información (DP, Participatory IT Design) y el diseño empresarial de modelos de negocio interactúan entre sí. Exploraremos el hueco que existe en los asuntos que aborda un proyecto de DP señalado por Kyng (2010). DP es una forma de enfocar el diseño para diseñar sistemas informáticos que tiene su propia ideología, haciendo mucho hincapié en la participación de los usuarios en el proceso. Esta ideología propia de DP da paso a un conjunto de métodos y herramientas para diseñar. DP tiene sus orígenes en Escandinavia en la década de los setenta cuando cambios de progreso social de la sociedad se introdujeron en el lugar de trabajo. Ya hay algunos investigadores del campo de DP que empiezan a estudiar este hueco señalado por Kyng. Un modelo de negocios es la forma en que un negocio crea, entrega y captura valor. En las últimas décadas las empresas informáticas han cambiado su modelo de negocios, transformándose en una oferta de servicios informáticos mayoritariamente. El mundo empresarial ya conoce los beneficios de las metodologías de diseño orientadas al usuario, sin embargo no acaban de ser adoptadas por las empresas informáticas. En el proyecto buscamos responder a las preguntas que surgen al juntar estas dos áreas de estudio. ¿Cómo interpreta la comunidad de DP el mundo empresarial? ¿La teoría empresarial como trata la metodología de diseño orientado al usuario? ¿Cómo afecta en una compañía real su política de usuario a su modelo de negocio y que técnicas utilizan para involucrar al usuario? ¿Qué intereses comunes y opuestos existen entre DP y el mundo empresarial? ¿Cuál es el futuro de DP en el mundo empresarial? En cuanto a la metodología del proyecto realice un estudio de la literatura de los campos de DP y el mundo empresarial usando fuentes recomendadas por expertos de cada área así como trabajos encontrados por mi propia cuenta que eran relevantes al tema tratado. Además realice un estudio de compañías desarrolladoras de software locales a Copenhague. Mediante una serie de visitas y entrevistas con esas compañías obtuve información del modelo de negocio y proceso de desarrollo de software de las mismas. También dialogamos en cuanto a su visión de DP y metodologías de diseño orientado al usuario y como se podrían beneficiar de ellas. Durante el desarrollo del proyecto he encontrado que DP y el mundo empresarial tienen dos visiones muy diferentes. Mientras uno busca obtener el máximo beneficio el otro busca apoderar a los usuarios en su área de trabajo. Aunque al igual que DP las empresas necesitan obtener información acerca de los usuario como sus necesidades, gustos, etc. Está claro que el software producido para el mundo empresarial tiene mucho espacio para mejorar ya que suele venir con manuales de instrucciones extensos y es necesario un entrenamiento previo para su utilización. Un problema importante de la introducción de DP en las empresas es la falta de predisposición de los usuarios en colaborar en el proceso de desarrollo ya que no hay demasiada tendencia a usuarios a dar feedback. El trabajo de investigacion de Timpka y Vimarlund (1998) Participatory Design In Economic Terms: A Theoretical Discussion llega a la conclusión de que DP es económicamente favorable para los desarrolladores. Pero omite muchos factores críticos de la economía de una empresa. En cuanto al futuro de DP en el mundo empresarial, DP tiene que adaptarse a las compañías desarrolladoras de software. A sus necesidades y teniendo en cuenta sus límites de recursos. Pero hay ciertos aspectos que deben ser abordados. El primer aspecto es el uso de recursos en las técnicas de DP, ya que utilizan demasiados. Otro aspecto que debería abordar es el uso de las nuevas tecnologías de comunicación y redes sociales, ya que apenas se han utilizado en DP. Mientras que otras áreas de estudio han hecho uso de estas nuevas tecnologías y se han revolucionado DP no ha sido capaz de integrarlas en sus técnicas. Por último en el proyecto realizo una comparativa del actual modelo de negocios y proceso de desarrollo de software de la compañía Forecast.it. En esta comparativa miro como cambiaria el negocio en el caso de que se produjeran cambios en ella al introducir la ideología de DP. Donde más se notan los cambios seria en su esquema de desarrollo de software ya que habría que hacer hueco para nuevos factores y pasos.

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Copolymer 1 [poly(Y,E,A,K)] is a random synthetic amino acid copolymer of l-tyrosine, l-glutamic acid, l-alanine, and l-lysine that is effective both in suppression of experimental allergic encephalomyelitis and in the treatment of relapsing forms of multiple sclerosis. Copolymer 1 binds promiscuously and very efficiently to purified HLA-DR molecules within the peptide-binding groove. In the present study, YEAK and YEAK-related copolymers and type II collagen (CII) peptide 261–273, a candidate autoantigen in rheumatoid arthritis (RA), competed for binding to RA-associated HLA-DR molecules encoded by DRB1*0101 and DRB1*0401. Moreover, these copolymers (particularly YEAK, YAK, and YEK) inhibited the response of DR1- and DR4-restricted T cell clones to the CII epitope 261–273 by >50%. This direct evidence both for competitive interactions of these copolymers and CII peptide with RA-associated HLA-DR molecules and for inhibition of CII-specific T cell responses suggests that these compounds should be evaluated in animal models for rheumatoid arthritis.

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Graves disease is an autoimmune thyroid disease characterized by the presence of antibodies against the thyrotropin receptor (TSHR), which stimulate the thyroid to cause hyperthyroidism and/or goiter. By immunizing mice with fibroblasts transfected with both the human TSHR and a major histocompatibility complex class II molecule, but not by either alone, we have induced immune hyperthyroidism that has the major humoral and histological features of Graves disease: stimulating TSHR antibodies, thyrotropin binding inhibiting immunoglobulins, which are different from the stimulating TSHR antibodies, increased thyroid hormone levels, thyroid enlargement, thyrocyte hypercellularity, and thyrocyte intrusion into the follicular lumen. The results suggest that the aberrant expression of major histocompatibility complex class II molecules on cells that express a native form of the TSHR can result in the induction of functional anti-TSHR antibodies that stimulate the thyroid. They additionally suggest that the acquisition of antigen-presenting ability on a target cell containing the TSHR can activate T and B cells normally present in an animal and induce a disease with the major features of autoimmune Graves.