1,274 research outputs found

    Solving multi-objective hub location problems by hybrid algorithms

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    In many logistic, telecommunications and computer networks, direct routing of commodities between any origin and destination is not viable due to economic and technolog- ical constraints. In that cases, a network with centralized units, known as hub facilities, and a small number of links is commonly used to connect any origin-destination pair. The purpose of these hub facilities is to consolidate, sort and transship e ciently any commodity in the network. Hub location problems (HLPs) consider the design of these networks by locating a set of hub facilities, establishing an interhub subnet, and routing the commodities through the network while optimizing some objective(s) based on the cost or service. Hub location has evolved into a rich research area, where a huge number of papers have been published since the seminal work of O'Kelly [1]. Early works were focused on analogue facility location problems, considering some assumptions to simplify network design. Recent works [2] have studied more complex models that relax some of these assumptions and in- corporate additional real-life features. In most HLPs considered in the literature, the input parameters are assumed to be known and deterministic. However, in practice, this assumption is unrealistic since there is a high uncertainty on relevant parameters, such as costs, demands or even distances. In this work, we will study the multi-objective hub location problems with uncertainty.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Anytime Algorithms for Multi-Objective Hub Location Problems

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    In many logistic, telecommunications and computer networks, direct routing of commodities between any origin and destination is not viable due to economic and technological constraints. Hub locations problems (HLPs) are considered in that cases, where the design of these networks are optimized based on some objective(s) related on the cost or service. A huge number of papers have been published since the seminal work of O’Kelly. Early works were focused on analogue facility location problems, considering some assumptions to simplify network design. Recent works have studied more complex models that relax some of these assumptions and incorporate additional real-life features. In most HLPs considered in the literature, the input parameters are assumed to be known and deterministic. However, in practice, this assumption is unrealistic since there is a high uncertainty on relevant parameters, such as costs, demands or even distances. As a result, a decision maker usually prefer several solutions with a low uncertainty in their objectives functions. In this work, anytime algorithms are proposed to solve the multi-objective hub location problems with uncertainty. The proposed algorithms can be stopped at any time, yielding a set of efficient solutions (belonging to the Pareto front) that are well spread in the objective space.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    RanBP2-Mediated SUMOylation Promotes Human DNA Polymerase Lambda Nuclear Localization and DNA Repair

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    Cellular DNA is under constant attack by a wide variety of agents, both endogenous and exogenous. To counteract DNA damage, human cells have a large collection of DNA repair factors. Among them, DNA polymerase lambda (Polλ) stands out for its versatility, as it participates in different DNA repair and damage tolerance pathways in which gap-filling DNA synthesis is required. In this work we show that human Polλ is conjugated with Small Ubiquitin-like MOdifier (SUMO) proteins both in vitro and in vivo, with Lys27 being the main target of this covalent modification. Polλ SUMOylation takes place in the nuclear pore complex and is mediated by the E3 ligase RanBP2. This post-translational modification promotes Polλ entry into the nucleus, which is required for its recruitment to DNA lesions and stimulated by DNA damage induction. Our work represents an advance in the knowledge of molecular pathways that regulate cellular localization of human Polλ, which are essential to be able to perform its functions during repair of nuclear DNA, and that might constitute an important point for the modulation of its activity in human cells

    Drag’N Drop

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    Drag & Drop es una aplicación web diseñada para la creación de problemas a partir de piezas, en la que al profesor se le plantea una nueva posibilidad de evaluar a sus alumnos. La aplicación web servirá como un entorno dedicado a la elaboración de preguntas y respuestas. Para responder a dichas preguntas, se proporcionan unos elementos llamados “piezas” al alumno que se encargará de utilizar para construir su respuesta. A su vez, el profesor al elaborar la pregunta establecerá la solución ideal del problema y el conjunto de “piezas” que los alumnos podrán utilizar para crear las suyas propias. El alumno al terminar la solución de un problema, la enviará al servidor. Este se encargará de evaluarla y comparar la solución del alumno con la solución ideal propuesta por el profesor.Finalmente el profesor será el encargado de examinar el ejercicio y ajustar la calificación, ya sea aceptando la que propone el sistema o indicando una propia

    La metodología de trabajo por proyectos aplicada a la elaboración del TFG por parte de futuros maestros de Educación Infantil en el EEES

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    Antecedentes: El Trabajo Fin de Grado en la Facultad de Ciencias de la Educación, Universidad de Sevilla, cumple en este curso 2014/2015 su segunda edición, cabe preguntarse a modo de problema de investigación: ¿cuál puede resultar la metodología más adecuada para construir un proceso de formación y capacitación profesional con futuros/as maestros/as de educación infantil? ¿qué relaciones establecen los/as maestros/as en formación inicial entre las prácticas universitarias, la docencia universitaria y su capacitación profesional? Método: Para este trabajo seleccionó una metodología de investigación acción sobre el estudio de caso centrado en un grupo de ocho estudiantes, Grado Educación Infantil. Las técnicas de investigación utilizadas son: análisis de contenido del diario de campo del docente, cuestionarios de evaluación, tutorías y revisión de los trabajos. Resultados: Existen relaciones entre el diseño de trabajo por proyectos elaborado por el profesor/investigador y el realizado por las estudiantes. Los/as estudiantes aprenden de modo coherente con una metodología de trabajo por proyectos, integrando y desarrollando las competencias profesionales de aprender a aprender, emprendimiento educativo, creatividad, innovación e investigación.Background: The Final Thesis in the Educational Science Faculty, University of Seville, accomplishes this year 2014/15 its second publication. It is possible to ask oneself by way of a research problem: Which methodology could be the most appropriate to develop a professional development programme with future pre-school teachers? What links do teachers, in initial teacher training, establish between school placements, university education and professional development? Methodology: For this project, participatory action research was chosen for a case study based on a group of eight students who are studying pre-school level education. The investigation techniques used are: an analysis of the content of the teacher‘s field diary, evaluation questionnaires, seminars and task inspections. Results: There is a link between project work design elaborated by the teacher or investigator, and that carried out by the students. Students learn in a coherent way, with project work methodology, integrating and developing the following professional skills; learning to learn, educational entrepreneurship, creativity, innovation and investigation

    The debate on Dissertations among the professors of Social and Legal Sciences in the University of Seville

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    Con la última ordenación académica de las enseñanzas universitarias oficiales (Real Decreto 1393/2007, de 29 de octubre) tiene su aparición la asignatura de Trabajo Fin de Grado (TFG); a través de ella se pretende que el alumno cierre su etapa de grado mediante un trabajo en el que se integren los conocimientos y las competencias adquiridas. El objetivo del trabajo es trasladar el resultado del debate que actualmente se está teniendo en los centros de economía y derecho de la Universidad de Sevilla sobre el desarrollo de la materia de Trabajo Fin de Grado, que abarca aspectos como el desarrollo normativo, reconocimiento de créditos, asignación de trabajos, metodología de trabajo y evaluación. El método de recogida de datos ha sido, mediante reuniones con profesores implicados en la asignatura y las diferentes comisiones de seguimiento de los TFG de los centros con los que se ha trabajado. El resultado obtenido muestra un alto grado de confusión e insatisfacción por parte del profesorado implicado en el estudio; se propone la necesidad de unificar la normativa, la mejora en el reconocimiento, se cuestiona la obligatoriedad de su realización y de su evaluación mediante defensa oral pública.The last official university teaching academic plan (Royal Decree 1393/2007, of 29th. October) has meant the emergence of a Final Year Project (FYP) as a subject. Its aim is for students to finish their degree period via work which brings together the knowledge and skills which they have acquired. This article’s goal is to shift the result of the debate that is currently taking place in the centres of economics and law of the University of Seville about working out the FYP. This subject encompasses aspects such as regulatory development, credit recognition, work allocations, work methodology and evaluation. The data collection method has been via meeting with the professors involved in the subject and the different follow-up commissions of the FYP in the centres concerned. The result shows the high degree of confusion and dissatisfaction of the teachers involved in the study. The need to unify the regulation and to improve the recognition is proposed. The subject’s mandatory nature and its evaluation via public presentation are also questioned

    Coupled-oscillator model to analyze the interaction between a quartz resonator and trapped ions

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    The novel application of a piezoelectric quartz resonator for the detection of trapped ions has enabled the observation of the quartz-ions interaction under nonequilibrium conditions, opening new perspectives for high-sensitive motional frequency measurements of radioactive particles. Energized quartz crystals have (long) decay-time constants in the order of milliseconds, permitting the coherent detection of charged particles within short time scales. In this paper we develop a detailed model governing the interaction between trapped 40Ca+ ions and a quartz resonator connected to a low-noise amplifier. We apply this model to experimental data and extract the ions’ reduced-cyclotron frequency in our 7-T Penning trap setup. We also obtain an upper limit for the coupling constant g with the present quartz-amplifier-trap (QAT) configuration. The study of the reduced-cyclotron frequency is especially important for the use of this resonator in precision Penning-trap mass spectrometry. The improvement in sensitivity can be accomplished by increasing the quality factor of the QAT configuration, which in turn will improve the performance of the system towards the strong-coupling regim

    Una espectadora ilustre en el patio de comedias de Logroño: la "Corregidora" de Burgos. A propósito de las relaciones de teatro y gobernante

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    p. 121-132En mi estudio sabre la vida teatral en La Rioja durante las siglos XVII y XVIII advertí que la situación qeoqráfica de esta región, fronteriza con el reino de Navarra, favorecía que en Logroño se dieran cita compañías de comedias de diversa procedencia, itinerarios y destinos par el norte de España. Me atreví entonces a establecer dos itinerarios en las movimientos de estas cornpanlas, que denorniné "eje araqonés" y "eje castellano". La ruta aragonesa tenia coma puntos principales Zaragoza,Tarazona, Tudela, Calahorra y Logrono, y la seguían las compañías procedentes de Valencia o Barcelona

    La excavación arqueológica del solar de la plaza de las Tenerías, nº 3-5 (Zaragoza)

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    Se presenta un avance de los resultados de las excavaciones realizadas en el solar de la plaza de Las Tenerías, no 3-5 (Zaragoza) que nos documenta, de forma excepcional, el sistema de drenaje utilizado por los romanos en un sector de la ciudad próximo a los ríos Ebro y Huerva. Entre lo más notable está el hallazgo de un áureo de Augusto y un conjunto compuesto por 814 ánforas romanas de tipologías diversas. El áureo fue descubierto entre los materiales arqueológicos que formaban parte del primer aterrazamiento asentado sobre el lecho natural de la terraza del río Ebro. Sobre él, más tarde, se realizó un segundo aterrazamiento. Esta nueva nivelación incluyó muros de mampostería, como elementos de contención, y las ánforas dispuestas vacías e invertidas con el fin de elevar y drenar el terreno a fin de evitar que las humedades ascendieran al suelo edificable

    Tandem Repeat DNA provides many cytological markers for hybrid zone analysis in two subspecies of the grasshopper chorthippus parallelus

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    Recent advances in next generation sequencing (NGS) have greatly increased our understanding of non-coding tandem repeat (TR) DNA. Here we show how TR DNA can be useful for the study of hybrid zones (HZ), as it serves as a marker to identify introgression in areas where two biological entities come in contact. We used Illumina libraries to analyse two subspecies of the grasshopper Chorthippus parallelus, which currently form a HZ in the Pyrenees. We retrieved a total of 152 TR sequences, and used fluorescent in situ hybridization (FISH) to map 77 families in purebred individuals from both subspecies. Our analysis revealed 50 TR families that could serve as markers for analysis of this HZ, using FISH. Differential TR bands were unevenly distributed between chromosomes and subspecies. Some of these TR families yielded FISH bands in only one of the subspecies, suggesting the amplification of these TR families after the geographic separation of the subspecies in the Pleistocene. Our cytological analysis of two TR markers along a transect of the Pyrenean hybrid zone showed asymmetrical introgression of one subspecies into the other, consistent with previous findings using other markers. These results demonstrate the reliability of TR-band markers for hybrid zone studie
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