575 research outputs found
Un programa de simulación como introducción a la geología aplicada, en primero de geológicas
Entre los meses de Abril y Junio de 1988, un grupo de clase de 70 alumnos de Geologia General (10 curso de licenciatura en Ciencias Geológicas) trabajó con un programa interactivo de ordenador que simula una situación de prospección petrolifera y otra de carbón, asi como la búsqueda de un emplazamiento para enterrar residuos radiactivos. Se presentan los resultados obtenidos y su control por contraste con otro grupo de clase de la misma asignatura que recibió iguales conceptos teóricos pero no participó en la experiencia. Estos resultados permiten apoyar la conclusión de que las mayores ventajas de este apoyo pedagógico concreto no puede constatarse en el ámbito académico, aunque si podrian serlo en el ejercicio inicial de la profesión. De todas formas, existen avances de tipo psicológico y afectivo que hacen la experiencia muy recomendable
Representaciones de la violencia en la poesía de la guerra civil española
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file (viewed on September 20, 2007)Vita.Includes bibliographical references.Thesis (Ph. D.) University of Missouri-Columbia 2007.Dissertations, Academic -- University of Missouri--Columbia -- Spanish.Este trabajo analiza las representaciones de la violencia en la poesía escrita en español durante la guerra civil española. Analizaremos diferentes aspectos temáticos de la violencia y compararemos el tratamiento retórico que tienen en poemas de autores nacionales y republicanos. El análisis detalla cómo diferentes aspectos de la violencia son representados de maneras diferentes por poetas de ambos bandos. Asimismo analizamos cómo los autores de cada bando mantienen una línea temática y retórica siempre cercana: el margen para la creacín fue muy estrecho. Los autores se sometían rigurosamente a una retórica que venía impuesta por el bando (la "comunidad") a la que pertenecían. Las ideas teóricas sobre la recepción de los textos de Stanley Fish y Wolfgang Iser proporcionan la base crítica para nuestro estudio
Air passenger demand forecast through the use of Artificial Neural Network algorithms
Airport planning depends to a large extent on the levels of activity that are anticipated. In order to plan facilities and infrastructures of an airport system and to be able to satisfy future needs, it is essential to predict the level and distribution of demand. This document presents a short- and medium-term forecast of the demand for air passengers carried out through a specific case study (Colombia), in which the impact of the pandemic period due to COVID-19 on air traffic was taken into account. To make the forecast, an algorithm that implements techniques based on Artificial Neural Networks (ANN) and Machine Learning (ML) was developed. In particular, for the analysis of the available time series, techniques of encoder-decoder networks of the type ConvLSTM2D have been applied. These architectures are a hybrid between Convolutional Neural Networks (CNN), very useful for the extraction of invariant patterns in their spatial position, and Recurrent Neural Networks (RNN), appropriate for the extraction of patterns within their temporal context (time series). The most relevant result of the present research is that the recovery in demand (volume and trend) to the levels reported before the pandemic is forecast for the period between the end of 2022 and the beginning of 2024 (depending on the type of traffic and scenario considered). Finally, the application of the forecasting model based on ML/Deep Learning (DL) presents, as a metric performance, a Mean Absolute Percentage Error (MAPE) values from 3% to 9% (depending on the scenario), which enables predictions of relative precision and introduces a new alternative technical approach to develop reliable air traffic forecasts, at least in the short and medium term
Air passenger demand forecast through the use of Artificial Neural Network algorithms
Airport planning depends to a large extent on the levels of activity that are anticipated. To plan the facilities and infrastructures of an airport system and to be able to satisfy future needs, it is essential to predict the level and distribution of demand. This document presents a short- and medium-term forecast of the demand for air passengers carried out through a specific case study (Colombia), in which the impact of the pandemic period due to COVID-19 on air traffic was taken into account. To make the forecast, an algorithm that implements techniques based on Artificial Neural Networks (ANN) (Machine Learning (ML)) was developed. In particular, for the analysis of the available time series, techniques of encoder-decoder networks of the type ConvLSTM2D have been applied. These architectures are a hybrid between Convolutional Neural Networks (CNN), very useful for the extraction of invariant patterns in their spatial position, and Recurrent Neural Networks (RNN), appropriate for the extraction of patterns within their temporal context (time series). The most relevant result of the present research is that the recovery in demand (volume and trend) to the levels reported before the pandemic is forecast for the period between the end of 2022 and the beginning of 2024 (depending on the type of traffic and scenario considered). Finally, the application of the forecasting model based on Machine Learning/Deep Learning (DL) presents, as a metric performance, a Mean Absolute Percentage Error (MAPE) value from 3% to 9% (depending on the scenario), which enables predictions of relative precision and introduces a new alternative technical approach to develop reliable air traffic forecasts, at least in the short and medium term
Multiserotype Protection Elicited by a Combinatorial Prime-Boost Vaccination Strategy against Bluetongue Virus
Bluetongue virus (BTV) belongs to the genus Orbivirus within the family Reoviridae. The development of vector-based vaccines expressing conserved protective antigens results in increased immune activation and could reduce the number of multiserotype vaccinations required, therefore providing a cost-effective product. Recent recombinant DNA technology has allowed the development of novel strategies to develop marker and safe vaccines against BTV. We have now engineered naked DNAs and recombinant modified vaccinia virus Ankara (rMVA) expressing VP2, VP7 and NS1 proteins from BTV-4. IFNAR(−/−) mice inoculated with DNA/rMVA-VP2,-VP7-NS1 in an heterologous prime boost vaccination strategy generated significant levels of antibodies specific of VP2, VP7, and NS1, including those with neutralizing activity against BTV-4. In addition, vaccination stimulated specific CD8+ T cell responses against these three BTV proteins. Importantly, the vaccine combination expressing NS1, VP2 and VP7 proteins of BTV-4, elicited sterile protection against a lethal dose of homologous BTV-4 infection. Remarkably, the vaccine induced cross-protection against lethal doses of heterologous BTV-8 and BTV-1 suggesting that the DNA/rMVA-VP2,-VP7,-NS1 marker vaccine is a promising multiserotype vaccine against BTV
Mechanistic Insights into the Cholesterol-dependent Binding of Perfringolysin O-based Probes and Cell Membranes
Cholesterol distribution in the cell is maintained by both vesicular and non-vesicular sterol transport. Non-vesicular transport is mediated by the interaction of membrane-embedded cholesterol and water-soluble proteins. Small changes to the lipid composition of the membrane that do not change the total cholesterol content, can significantly affect how cholesterol interacts with other molecules at the surface of the membrane. The cholesterol-dependent cytolysin Perfringolysin O (PFO) constitutes a powerful tool to detect cholesterol in membranes, and the use of PFO-based probes has flourished in recent years. By using a non-lytic PFO derivative, we showed that the sensitivity of the probes for cholesterol can be tuned by modifications introduced directly in the membrane-interacting loops and/or by modifying residues away from the membrane-interacting domain. Through the use of these biosensors on live RAW 264.7 cells, we found that changes in the overall cholesterol content have a limited effect on the average cholesterol accessibility at the surface of the membrane. We showed that these exquisite biosensors report on changes in cholesterol reactivity at the membrane surface independently of the overall cholesterol content in the membrane
Influence of Reynolds number on theoretical models for trailing vortices
We conduct direct numerical simulations for a NACA0012 airfoil at Reynolds numbers (Re) ranging from 300 to 7000 to determine the wake behavior behind this wing profile. We characterize the structure of the wing-tip vortex, finding a reasonable agreement with experimental results at Re=7000. In addition, we model the trailing vortex theoretically, thus obtaining the parameters for Batchelor’s and Moore and Saffman’s models. We compare the results of the best fitting for the axial vorticity and the azimuthal velocity, finding only small discrepancies. The main contribution of this research work is to study the evolution of these theoretical parameters as function of the Reynolds number. We observe that the wake becomes unstable at Re ≈1200, in agreement with previous results. These instabilities in the wake behind the wing produce a change in the trend of theoretical parameters (keywords: vortex dynamics, trailing vortices, theoretical models).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Preliminary Evaluation of Tick Protein Extracts and Recombinant Ferritin 2 as Anti-tick Vaccines Targeting Ixodes ricinus in Cattle
Anti-tick vaccines have the potential to be an environmentally friendly and cost-effective option for tick control. In vaccine development, the identification of efficacious antigens forms the major bottleneck. In this study, the efficacy of immunization with recombinant ferritin 2 and native tick protein extracts (TPEs) against Ixodes ricinus infestations in calves was assessed in two immunization experiments. In the first experiment, each calf (n = 3) was immunized twice with recombinant ferritin 2 from I. ricinus (IrFER2), TPE consisting of soluble proteins from the internal organs of partially fed I. ricinus females, or adjuvant, respectively. In the second experiment, each calf (n = 4) was immunized with protein extracts from the midgut (ME) of partially fed females, the salivary glands (SGE) of partially fed females, a combination of ME and SGE, or adjuvant, respectively. Two weeks after the booster immunization, calves were challenged with 100 females and 200 nymphs. Blood was collected from the calves before the first and after the second immunization and fed to I. ricinus females and nymphs using an in vitro artificial tick feeding system. The two calves vaccinated with whole TPE and midgut extract (ME) showed hyperemia on tick bite sites 2 days post tick infestation and exudative blisters were observed in the ME-vaccinated animal, signs that were suggestive of a delayed type hypersensitivity (DTH) reaction. Significantly fewer ticks successfully fed on the three animals vaccinated with TPE, SGE, or ME. Adults fed on the TPE and ME vaccinated animals weighed significantly less. Tick feeding on the IrFER2 vaccinated calf was not impaired. The in vitro feeding of serum or fresh whole blood collected from the vaccinated animals did not significantly affect tick feeding success. Immunization with native I. ricinus TPEs thus conferred a strong immune response in calves and significantly reduced the feeding success of both nymphs and adults. In vitro feeding of serum or blood collected from vaccinated animals to ticks did not affect tick feeding, indicating that antibodies alone were not responsible for the observed vaccine immunity
Península y Mediterráneo: relaciones en la cuenca occidental a finales del II Milenio a.C.
El inicio de esta investigación vendría marcado por una conversación con el Dr. José C. Martín de la Cruz ,que empezó con el estudio del material arqueológico de uno de los cortes del yacimiento de Llanete de los Moros y prosiguió con interminables coloquios sobre las comunidades prehistóricas que ocupaban el Valle Medio del Guadalquivir a finales de la Edad del Bronce, terminando con una pregunta ¿Cómo se producían los contactos entre estas comunidades? Desde tiempos prehistóricos han existido relaciones entre hombres y entre sociedades, es un hecho que se corrobora a través de: desplazamientos de pueblos, guerras de conquista, intercambios comerciales, etc. Lo que nos lleva a reflexionar sobre algunos interrogantes que nos asaltan, tales como motivaciones, formas de contactos, comunicacione, etc
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