4,450 research outputs found
Joint effect of ageing and multilayer structure prevents ordering in the voter model
The voter model rules are simple, with agents copying the state of a random
neighbor, but they lead to non-trivial dynamics. Besides opinion processes, the
model has also applications for catalysis and species competition. Inspired by
the temporal inhomogeneities found in human interactions, one can introduce
ageing in the agents: the probability to update decreases with the time elapsed
since the last change. This modified dynamics induces an approach to consensus
via coarsening in complex networks. Additionally, multilayer networks produce
profound changes in the dynamics of models. In this work, we investigate how a
multilayer structure affects the dynamics of an ageing voter model. The system
is studied as a function of the fraction of nodes sharing states across layers
(multiplexity parameter q ). We find that the dynamics of the system suffers a
notable change at an intermediate value q*. Above it, the voter model always
orders to an absorbing configuration. While, below, a fraction of the
realizations falls into dynamical traps associated to a spontaneous symmetry
breaking in which the majority opinion in the different layers takes opposite
signs and that due to the ageing indefinitely delay the arrival at the
absorbing state.Comment: 10 pages, 8 figure
Rentabilidad de los fondos de inversión de renta variable nacional en España (1991-2006)
La rentabilidad media de los fondos de inversión en renta variable nacional durante los tres, cinco, diez y quince últimos años fue inferior a la del ITBM (Indice Total de la Bolsa de Madrid) en más de un 6%. De los 43 fondos con diez años de historia, sólo uno (Bestinver Bolsa, que hizo honor a su nombre) consiguió una rentabilidad superior a la del ITBM. Veinticuatro de estos fondos tuvieron todos los años una rentabilidad inferior a la del ITBM. Sólo dos de los 99 fondos con tres años de historia consiguieron una rentabilidad superior al ITBM (Bestinver Bolsa y Metavalor). Si la rentabilidad de cada fondo de inversión en los últimos quince años no hubiera sido la realmente obtenida, sino la del ITBM, la apreciación de los fondos en el período 1991-2006 habría sido de 13.753 millones de euros en lugar de los 6.480 millones de euros que obtuvieron. El total de comisiones y gastos repercutidos en este período ascendió a unos 1.400 millones de euros. El resto se debe a comisiones ocultas y a decisiones de inversión mejorables.fondos de inversión; rentabilidad partícipes; benchmark; apreciación fondos;
Rentabilidad de los fondos de inversión en España. (1991-2006)
En los últimos cinco y diez años, la rentabilidad promedio de los fondos de inversión fue inferior a la inflación. A pesar de estos resultados, el 31 de diciembre de 2006, 8.819.809 partícipes tenían un patrimonio de 254.306 millones de euros en los 2.779 fondos de inversión existentes. En 2006 se lanzaron al mercado 246 nuevos fondos. Sólo 23 de los 649 fondos con diez años de historia han obtenido una rentabilidad superior al benchmark utilizado. Por ejemplo, de los 43 fondos de "renta variable nacional" con diez años de historia, sólo uno consiguió una rentabilidad superior a la del Indice Total de la Bolsa de Madrid. Si la rentabilidad de cada fondo de inversión en los últimos cinco años no hubiera sido la realmente obtenida, sino el benchmark de su categoría, la apreciación de los fondos en el período 2002-2006 habría sido 67.768 millones de euros en lugar de los 28.013 millones que obtuvieron. El total de comisiones y gastos repercutidos en este período ascendió a 12.805 millones de euros.fondos de inversión; rentabilidad partícipes; benchmark; apreciación fondos;
Drone configuration for seaside rescue missions
The project is based on creating a first aid tool to perform a coastline rescue with an unmanned. The System is formed by a ground segment, where the ground station will be placed and an air segment, where the unmanned vehicle, equipped with all the necessary extra devices to perform the mission will be found. For notices of possible drownings, the ground station will receive notifications that users will publish using a Mobile application. This app will allow users to capture images of the victim location and push them to the server, which will re-direct the information to the station covering that location. The operator will be responsible of starting the mission. This operation will follow a pre- established route, generated by the processor, according to the requests of the operator. To generate the mentioned routes, first, will be necessary to create an operating model suitable for the location of the mission, this model will be defined with an extended markup language file. The mission is made up of different stages, similarly to the civil operations. The scan and launch phase stand out among the all steps. In these both paths the vehicle will scan the are to find the victim and deploy the floater once the victim is found. The vehicle control is done via a visual interface and communication with the air segment will be established by radio. In case of failure, the system will have 4G coverage to continue the operation. The unmanned aircraft is in charge of performing the mission (controlled by the operator). To operate the mission autonomously, the unmanned vehicle is equipped with an autopilot system, which will perform the flight plans uploaded by the processor. In addition of the radio communication and the autopilot, the vehicle will be equipped with one floater, which will be deployed to give support to the victim. If during the mission, some kind of problem arises, the operator may request an emergency recovery sequence. Otherwise, in case that everything is working perfectly the platform will be recovered tracing back its previous steps or in a direct recover if the battery level starts to be critical
Implementación de los modelos gráficos probabilísticos bayesianos en la ayuda al manejo clínico de la bronquiolitis aguda del lactante
Fecha de Lectura de Tesis: 6 de Abril de 2018.La Bronquiolitis Aguda (BA) del lactante supone el mayor motivo de ingreso hospitalario de los Servicios de Pediatría en general y una de las causas de mayor ocupación, consumo de recursos y estancias hospitalarias. En torno al 3-5% de la BAs precisará ingreso en un hospital, el 6-16% de los ingresados acabará en cuidados intensivos y un 3-8% de los ingresos sufrirá episodios de apnea.
El objetivo de la investigación es la confección y desarrollo de un modelo gráfico probabilístico Naïve Bayes (NB) selectivo, utilizado como herramienta de epidemiología clínica, para la predicción de la evolución grave y de la aparición de apneas en la BA del lactante.
La metodología se basa en el estudio de los factores de riesgo de evolución grave y de aparición de apneas durante el ingreso en la BA sobre la experiencia de un hospital de tercera referencia, la elaboración de una red probabilística NB mediante OpenMarkov (modelo gráfico probabilístico) y la implementación del modelo tras evaluación de la sensibilidad y especificidad de sus predicciones para conocer prospectivamente su validez y fiabilidad comparado con un modelo de regresión logística.
Por ello se plantearon unos objetivos específicos, como el análisis epidemiológico general de una amplia serie de casos de BA durante las epidemias desde octubre-2010 hasta marzo-2015, para conocer su realidad en un espacio-tiempo concreto. Además, para estimar la incidencia de apneas en pacientes hospitalizados por BA y estudiar los factores de riesgo relacionados con su aparición y también conocer la incidencia de ingresos en UCIP para VM y estudiar los factores asociados a mala evolución, centrado este aspecto sobre el agente etiológico primordial en casos graves de BA: el VRS. En cada caso se utilizó el procedimiento de regresión logística (RL) y se estimó su capacidad de predicción
Estudio de los endófitos presntes en las raíces de Posidonia oceánica y su capacidad antagonista frente a Pythium aphanidermatum
Melanoma expression analysis with Big Data technologies
Melanoma is a highly immunogenic tumor. Therefore, in recent years physicians have incorporated drugs that alter the immune system into their therapeutic arsenal against this disease, revolutionizing in the treatment of patients in an advanced stage of the disease. This has led us to explore and deepen our knowledge of the immunology surrounding melanoma, in order to optimize its approach. At present, immunotherapy for metastatic melanoma is based on stimulating an individual’s own immune system through the use of specific monoclonal antibodies. The use of immunotherapy has meant that many of patients with melanoma have survived and therefore it constitutes a present and future treatment in this field. At the same time, drugs have been developed targeting specific mutations, specifically BRAF, resulting in large responses in tumor regression (set up in this clinical study to 18 months), as well as a higher percentage of long-term survivors. The analysis of the gene expression changes and their correlation with clinical changes can be developed using the tools provided by those companies which currently provide gene expression platforms. The gene expression platform used in this clinical study is NanoString, which provides nCounter. However, nCounter has some limitations as the type of analysis is restricted to a predefined set, and the introduction of clinical features is a complex task. This paper presents an approach to collect the clinical information using a structured database and a Web user interface to introduce this information, including the results of the gene expression measurements, to go a step further than the nCounter tool. As part of this work, we present an initial analysis of changes in the gene expression of a set of patients before and after targeted therapy. This analysis has been carried out using Big Data technologies (Apache Spark) with the final goal being to scale up to large numbers of patients, even though this initial study has a limited number of enrolled patients (12 in the first analysis). This is not a Big Data problem, but the underlaying study aims at targeting 20 patients per year just in Málaga, and this could be extended to be used to analyze the 3.600 patients diagnosed with melanoma per year.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. This work was funded in part by Grants TIN2014-58304-R (Ministerio de Ciencia e Innovación) and P11-TIC-7529 and P12-TIC-1519 (Plan Andaluz de Investigación, Desarrollo e Innovación). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
In vitro regeneration and genetic fidelity of Tigridia pavonia (L.f.) DC.
Plants of Tigridia pavonia (L.f.) DC were regenerated from twin-scaling explants cultured on Murashige and Skoog and N6 basal medium. The highest formation of shoots per responding explant was obtained on N6 medium supplemented with 4.5 µM 2,4-dichlorophenoxy acetic acid in combination with 2.2 µM benzylaminopurine. Shoots rooted readily on N6 basal medium supplemented with 1 g l-1 activated charcoal and 2.6 µM naphtalenacetic acid. The rooted shoots achieved 100% survival. Inter Simple Sequence Repeat analysis was carried out to check for possible genetic alterations in plants obtained after two consecutive subcultures. The results revealed that the recovered plants did not exhibit any type of polymorphism
Variety discrimination of Tigridia pavonia (L.f.) DC. assesed by different length RAPD primers
Tigridia pavonia (L.f.) DC. is one of the important phytogenetic resources of México. This species is used as ornamental, food and medicinal purposes. Despite its ornamental and economic potential, there is little information about the genetic variability. In this study, randomly amplified polymorphic DNA (RAPD) primers of 10, 15 and 20 bases were used to assess the level of genetic variation among nine botanical varieties of Tigridia pavoniacollected in three localities within State of México. The total number fragments, polymorphic fragments, percentage of polymorphism and resolving power were greater for 15 base (55, 52, 94.5 and 5, respectively) and 20 base (47, 45, 95.7 and 3.8, respectively), in comparison with those obtained from 10 base primers (44, 41, 93.1 and 3.6, respectively).Resultsshowed the major effectiveness of 15 and 20 bases RAPD primers in the genetic differentiation of varieties as compared to 10 bases RAPD primers. The dendrograms based on un-weighted pair group method arithmetic average (UPGMA) analysis of the 10, 15, 20 and the pooled (10, 15 and 20) bases RAPD data were consistent in the clustering varieties, grouping them in two main clusters
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