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Photoreception in Ambulacraria: A Comprehensive Approach
Non-directional photoreceptors are the evolutionary precursors of all animal eyes; they enable the monitoring of ambient light intensity and regulate feeding, movement and reproduction. While the first animals were most likely benthic, they evolved larval stages very early on, thus conquering a new ecological niche: the pelagic. In this realm, the evolutionary pressure to prey but not be preyed upon became stronger. This implied strong selection for better sensory systems, including photoreception. How were the photoreceptor systems of the earliest primary larvae arranged? Did this system mediate vertical migration, the largest movement of biomass on Earth? To try to answer these questions, I chose the pluteus larva of the sea urchin as a model. A comprehensive array of techniques was applied, covering levels of organization from genes to behaviour. The diversity of opsins in Ambulacraria (echinoderms plus hemichordates) has been surveyed to have the first phylogenetic context on this matter (Chapter 1). A nondirectional photoreceptor based on Go-opsins has been first described in an invertebrate larva of the deuterostome lineage (Chapter 2). A novel custom built behavioural set up was created to investigate the vertical migration of these pluteus larvae under different light conditions (Chapter 3). Based on these findings, a mechanistic model for understanding simple photodetection is proposed
Quasiperiodic graphs at the onset of chaos
We examine the connectivity fluctuations across networks obtained when the
horizontal visibility (HV) algorithm is used on trajectories generated by
nonlinear circle maps at the quasiperiodic transition to chaos. The resultant
HV graph is highly anomalous as the degrees fluctuate at all scales with
amplitude that increases with the size of the network. We determine families of
Pesin-like identities between entropy growth rates and generalized
graph-theoretical Lyapunov exponents. An irrational winding number with pure
periodic continued fraction characterizes each family. We illustrate our
results for the so-called golden, silver and bronze numbers.Comment: arXiv admin note: text overlap with arXiv:1205.190
El papel del MECI como instrumento de gestión en los municipios de Sabana Centro
Los mecanismos adoptados a nivel estatal con el objeto de regular las dinámicas de gestión de las entidades públicas no muchas veces cumplen con la tarea asignada. El MECI, propuesto como mecanismo oficial para lograr unificar el proceso de control interno de las entidades del estado no hace la excepción. El texto presenta un análisis sobre la aplicación del MECI en algunos municipios de la sabana, afirmando que su aplicación ha sido simplemente una cuestión accesoria de cumplimiento de requisitos más que una implementación estricta que cumpla con los planteamientos especificados por el model
WSM : metodología de web scraping para Android y ejemplificación mediante la aplicación UPMDroid
En la realización de este proyecto se ha tratado principalmente la temática del web scraping sobre documentos HTML en Android. Como resultado del mismo, se ha propuesto una metodología para poder realizar web scraping en aplicaciones implementadas para este sistema operativo y se desarrollará una aplicación basada en esta metodología que resulte útil a los alumnos de la escuela.
Web scraping se puede definir como una técnica basada en una serie de algoritmos de búsqueda de contenido con el fin de obtener una determinada información de páginas web, descartando aquella que no sea relevante. Como parte central, se ha dedicado bastante tiempo al estudio de los navegadores y servidores Web, y del lenguaje HTML presente en casi todas las páginas web en la actualidad así como de los mecanismos utilizados para la comunicación entre cliente y servidor ya que son los pilares en los que se basa esta técnica.
Se ha realizado un estudio de las técnicas y herramientas necesarias, aportándose todos los conceptos teóricos necesarios, así como la proposición de una posible metodología para su implementación.
Finalmente se ha codificado la aplicación UPMdroid, desarrollada con el fin de ejemplificar la implementación de la metodología propuesta anteriormente y a la vez desarrollar una aplicación cuya finalidad es brindar al estudiante de la ETSIST un soporte móvil en Android que le facilite el acceso y la visualización de aquellos datos más importantes del curso académico como son: el horario de clases y las calificaciones de las asignaturas en las que se matricule.
Esta aplicación, además de implementar la metodología propuesta, es una herramienta muy interesante para el alumno, ya que le permite utilizar de una forma sencilla e intuitiva gran número de funcionalidades de la escuela solucionando así los problemas de visualización de contenido web en los dispositivos.
ABSTRACT.
The main topic of this project is about the web scraping over HTML documents on Android OS. As a result thereof, it is proposed a methodology to perform web scraping in deployed applications for this operating system and based on this methodology that is useful to the ETSIST school students.
Web scraping can be defined as a technique based on a number of content search algorithms in order to obtain certain information from web pages, discarding those that are not relevant. As a main part, has spent considerable time studying browsers and Web servers, and the HTML language that is present today in almost all websites as well as the mechanisms used for communication between client and server because they are the pillars which this technique is based.
We performed a study of the techniques and tools needed, providing all the necessary theoretical concepts, as well as the proposal of a possible methodology for implementation.
Finally it has codified UPMdroid application, developed in order to illustrate the implementation of the previously proposed methodology and also to give the student a mobile ETSIST Android support to facilitate access and display those most important data of the current academic year such as: class schedules and scores for the subjects in which you are enrolled.
This application, in addition to implement the proposed methodology is also a very interesting tool for the student, as it allows a simple and intuitive way of use these school functionalities thus fixing the viewing web content on devices
Restoration Project of vernacular architecture affected for ground subsidence. A case study in Juslibol Church (Zaragoza, Spain)
[EN] At the request of the Archbishopric of Zaragoza, an exhaustive study of the situation of the parish church
dedicated to the Assumption of Our Lady (18th century) in Juslibol (Zaragoza) has been carried out since
2011. It was built between 1758 and 1784. The church was built on a hillside with a medium-low slope,
excavating in a loose colluvial soil formed by silt-clay materials with fragments of marl-gypsum rock. and
pebbles of gravel and sand from the terrace deposits located in the highest part of the slope. Once the plot
was leveled, the ground would be prepared and the foundation elements would be excavated (apparently
continuous trenches) according to the design of the projected building floor plan. This church has suffered
for many years from deformation and settling problems caused by the combination of several especially
unfavorable factors, such as: the poor quality of the support ground, its sloped location halfway up the
hillside, and leaks-filtrations from a supply network, and especially sanitation, which have favored processes of dissolution-undermining of the land below the foundations. The part facing south, including the
tower, registered differential settlements with respect to the part further into the hillside. Once this situation
was assessed, it was underpinned by means of jet-grouting columns and, apparently, the measure was
effective. However, the cracks now observed are not explained within a differential settlement process.Gracia, A.; Torrijo, FJ.; Pérez, M. (2022). Restoration Project of vernacular architecture affected for ground subsidence. A case study in Juslibol Church (Zaragoza, Spain). Editorial Universitat Politècnica de València. 855-862. https://doi.org/10.4995/HERITAGE2022.2022.1513385586
Correlación de constantes críticas a partir de la ecuación de Van der Waals
The cubic van der Waals equation of state at the critical condition is reduced to a linear function (Vc vs. Tc /Pc coordinates) with one adjustable parameter. It is shown that at the critical point the relation Vc = 3Vo must not hold as van der Waals suggested, but the attractive constant α = Pc Vc2 remains. Selected values of Tc, Pc, Vc compiled by Ihmels where focused on testing the quality of several empirical equations relating critical conditions. It is shown that the obtained critical constants correlation is a general form of the empirical expressions proposed by Young, Meissner, Bird, Grigoras and Ihmels. From the resulting correlation function, a function for the critical compressibility is proposed. The critical volume Vc and the ratio Tc /Pc have been expressed in group contributions.La ecuación de estado cúbica de van der Waals en la condición crítica se reduce a una función lineal (en coordenadas Vc frente a Tc /Pc) con un parámetro de ajuste. Se muestra que en el punto crítico, la constante Vc = 3Vo debe efectivamente descartarse como hizo van der Waals, no así con la constante atractiva α = Pc Vc2. Los valores seleccionados de Tc, Pc, Vc compilados por Ihmels se enfocaron en probar la calidad de varias ecuaciones empíricas renombradas que relacionan condiciones críticas. En este artículo se muestra que la correlación de constantes crítica obtenida es una forma general de estas expresiones empíricas propuestas por Young, Meissner, Bird, Grigoras e Ihmels. Se propone una función para la compresibilidad crítica, única por familia homóloga. El volumen crítico Vc y la relación Tc /Pc se expresa en función de contribución de grupos
Análisis comparativo entre las especificaciones técnicas de mezclas densas para pavimentos de carreteras colombianas y brasileras
Artículo de investigaciónEl presente trabajo tiene como finalidad identificar las principales características de las mezclas asfálticas utilizadas en Colombia frente a las adoptadas en la normativa brasilera, las fuentes de información principal son los documentos del Instituto Nacional de Vías INVIAS para Colombia y el Departamento Nacional de Infraestructura de Transportes DNIT de Brasil. Esto con el fin de evaluar la mejor condición frente a normatividad vigente en cuanto a calidad y exigencia de especificaciones de materiales, procedimientos de diseño y ensayos.RESUMEN
INTRODUCCIÓN
METODOLOGÍA
RESULTADOS
ANÁLISIS DE RESULTADOS
ANEXOSEspecializaciónEspecialista en Ingeniería de Pavimento
Two Frequenins in Drosophila: unveiling the evolutionary history of an unusual Neuronal Calcium Sensor (NCS) duplication
13 pages, 4 figures, 1 table, 5 additional files.[Background] Drosophila Frequenin (Frq), the homolog of the mammalian Neuronal Calcium Sensor-1 (NCS-1), is a high affinity calcium-binding protein with ubiquitous expression in the nervous system. This protein has an important role in the regulation of neurotransmitter release per synapse, axonal growth and bouton formation. In D. melanogaster, Frequenin is encoded by two genes (frq1 and frq2), a very unexpected feature in the Frq/NCS-1 subfamily. These genes are located in tandem in the same genomic region, and their products are 95% identical in their amino acid sequence, clearly indicating their recent origin by gene duplication. Here, we have investigated the factors involved in this unusual feature by examining the molecular evolution of the two frq genes in Drosophila and the evolutionary dynamics of NCS family in a large set of bilaterian species.[Results] Surprisingly, we have found no amino acid replacements fixed across the twelve Drosophila species surveyed. In contrast, synonymous substitutions have been prevalent in the evolution of the coding region of frq1 and frq2, indicating the presence of strong functional constraints following gene duplication. Despite that, we have detected that significant evolutionary rate acceleration had occurred in Frq1 in early times from the duplication, in which positive selection (likely promoting functional diversification) had probably an important role. The analysis of sequence conservation and DNA topology at the non-coding regions of both genes has allowed the identification of DNA regions candidates to be cis-regulatory elements. The results reveal a possible mechanism of regulatory diversification between frq1 and frq2.[Conclusions] The presence of two Frequenins in Drosophila and the rapid accumulation of amino acid substitutions after gene duplication are very unusual features in the evolution of the Frq/NCS-1 subfamily. Here we show that the action of positive selection in concordance with some extent of regulatory diversification might explain these findings. Selected amino acid substitutions in Frq1 likely contributed to the functional divergence between the two duplicates, which, in turn, should have diverged in their regulation by Ecdysone-induced early genes.Research
was funded by grants BFU 2006-10180 and the European Research Network
of Excellence MYORES ref.: CE-511978.Peer reviewe
Towards Data-driven Software-defined Infrastructures
Abstract The abundance of computing technologies and devices imply that we will live in a data-driven society in the next years. But this data-driven society requires radically new technologies in the data center to deal with data manipulation, transformation, access control, sharing and placement, among others. We advocate in this paper for a new generation of Software Defined Data Management Infrastructures covering the entire life- cycle of data. On the one hand, this will require new extensible programming abstractions and services for data-management in the data center. On the other hand, this also implies opening up the control plane to data owners outside the data center to manage the data life cycle. We present in this article the open challenges existing in data-driven software defined infrastructures and a use case based on Software Defined Protection of data
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