Bòbila d’Ermedàs: Estudi del material arqueològic de la UE-115

Estudi del material trobat a l’interior d’una de les tres canals presents en el jaciment d’Ermedàs recuperat durant la 6a i 7a campanyes d’excavació, al 2004 i 2006, en què es va excavar l’estructura. El conjunt a analitzar correspon al moment de l’abandó de la canalització, indicatiu que ens trobem davant un conjunt tancat. L’objectiu és analitzar un grup de material ceràmic que serveix per datar i contextualitzar la canalització dins el funcionament global de la bòbila d’Ermedàs, per tal de poder conèixer una part més del seu funcionament

Càlcul, disseny i fabricació d'una carrosseria autoportant en material compòsit per al vehicle de baix consum Àliga

El projecte és l’inici de la creació d’un nou prototip per a poder competir la temporada 2008 a la cursa de vehicles de baix consum Shell Eco-Marathon. El principal objectiu és aconseguir un xassís que redueixi, en la mesura del possible, el pes del prototip a la vegada que asseguri una millor rigidesa i millori l’ergonomia de tot el conjunt. Es dissenyarà tota la part estructural de la carrosseria, que serà sotmesa a càlcul mitjançant la tècnica dels elements finits i posteriorment es realitzarà una guia de producció per tal de guiar els membres de l’equip que en realitzin la producció

Interoperabilitat entre repositoris de material docent i recol·lectors de metadades

L'objectiu principal d'aquest projecte és estudiar les mancances en la interoperabilitat entre els repositoris de material docent i els recol·lectors de metadades, així com incloure una proposta d'arquitectura per superar-ho, basada en ontologies per a cada tipus de material docent o mitjançant crosswalks.

Statistical similarity between the compression of a porous material and earthquakes

It has been long stated that there are profound analogies between fracture experiments and earthquakes; however, few works attempt a complete characterization of the parallelisms between these so separate phenomena. We study the Acoustic Emission events produced during the compression of Vycor (SiO&sub&2&/sub&). The Gutenberg-Richter law, the modified Omori's law, and the law of aftershock productivity hold for a minimum of 5 decades, are independent of the compression rate, and keep stationary for all the duration of the experiments. The waiting-time distribution fulfills a unified scaling law with a power-law exponent close to 2.45 for long times, which is explained in terms of the temporal variations of the activity rate.

Implantació d'un sistema ERP per a gestionar una empresa dedicada a la producció i distribució de material odontològic

Aquest projecte tracta sobre la implantació d'un sistema ERP per tal de gestionar una empresa dedicada a la producció i distribució de material odontològic. El que durem a terme en aquesta aplicació serà importar les dades de l'aplicació VolkSoft a la nova aplicació. La idea principal es buscar una aplicació que satisfaci les necessitats de l'aplicació VolkSoft i a continuació, importar les dades d'una aplicació a l'altra.

Guiding students through competence-based educational material

Student guidance is an always desired characteristic in any educational system, butit represents special difficulty if it has to be deployed in an automated way to fulfilsuch needs in a computer supported educational tool. In this paper we explorepossible avenues relying on machine learning techniques, to be included in a nearfuture -in the form of a tutoring navigational tool- in a teleeducation platform -InterMediActor- currently under development. Since no data from that platform isavailable yet, the preliminary experiments presented in this paper are builtinterpreting every subject in the Telecommunications Degree at Universidad CarlosIII de Madrid as an aggregated macro-competence (following the methodologicalconsiderations in InterMediActor), such that marks achieved by students can beused as data for the models, to be replaced in a near future by real data directlymeasured inside InterMediActor. We evaluate the predictability of students qualifications, and we deploy a preventive early detection system -failure alert-, toidentify those students more prone to fail a certain subject such that correctivemeans can be deployed with sufficient anticipation.

Plantillas para la creación de material docente accesible con herramientas ofimáticas y LaTex

Existen distintos tipos de dificultades de accesibilidad entre los alumnos que cursan sus estudios en nuestras facultades. Podemos encontrar por ejemplo algunos alumnos ciegos o con diferentes grados de baja visión, incluyendo los problemas debidos a la edad (presbicia o vista cansada), también alumnos con trastornos de aprendizaje como dislexia o TDAH o alumnos que sufren dificultades de acceso derivadas de los dispositivos que usan para la conexión (con pantallas muy pequeñas). La accesibilidad, como disciplina, pretende mejorar las condiciones de acceso a la información de todos ellos.El proyecto “Recursos docentes accesibles” (2010-2012), en el marco del Programa de Mejora e Innovación Docente de la Universidad de Barcelona, se centra en la baja visión y en la dislexia. El objetivo principal es crear y poner a disposición de todo el profesorado y de los responsables académicos de las titulaciones de la Universidad de Barcelona un conjunto de plantillas y modelos de documentos docentes accesibles en origen y fácilmente transformables a versiones ampliadas o mejoradas. El proyecto se desarrolla en la Facultad de Biblioteconomía y Documentación y la Facultad de Matemáticas y ha contado con la colaboración de numerosos docentes. La previsión es extender este proyecto a otras universidades con la esperanza que, entre todos, podamos mejorar los problemas de accesibilidad de los documentos docentes.

Defective TNF-alpha-mediated hepatocellular apoptosis and liver damage in acidic sphingomyelinase knockout mice

This study addressed the contribution of acidic sphingomyelinase (ASMase) in TNF-alpha-mediated hepatocellular apoptosis. Cultured hepatocytes depleted of mitochondrial glutathione (mGSH) became sensitive to TNF-alpha, undergoing a time-dependent apoptotic cell death preceded by mitochondrial membrane depolarization, cytochrome c release, and caspase activation. Cyclosporin A treatment rescued mGSH-depleted hepatocytes from TNF-alpha-induced cell death. In contrast, mGSH-depleted hepatocytes deficient in ASMase were resistant to TNF-alpha-mediated cell death but sensitive to exogenous ASMase. Furthermore, although in vivo administration of TNF-alpha or LPS to galactosamine-pretreated ASMase(+/+) mice caused liver damage, ASMase(-/-) mice exhibited minimal hepatocellular injury. To analyze the requirement of ASMase, we assessed the effect of glucosylceramide synthetase inhibition on TNF-alpha-mediated apoptosis. This approach, which blunted glycosphingolipid generation by TNF-alpha, protected mGSH-depleted ASMase(+/+) hepatocytes from TNF-alpha despite enhancement of TNF-alpha-stimulated ceramide formation. To further test the involvement of glycosphingolipids, we focused on ganglioside GD3 (GD3) because of its emerging role in apoptosis through interaction with mitochondria. Analysis of the cellular redistribution of GD3 by laser scanning confocal microscopy revealed the targeting of GD3 to mitochondria in ASMase(+/+) but not in ASMase(-/-) hepatocytes. However, treatment of ASMase(-/-) hepatocytes with exogenous ASMase induced the colocalization of GD3 and mitochondria. Thus, ASMase contributes to TNF-alpha-induced hepatocellular apoptosis by promoting the mitochondrial targeting of glycosphingolipids.

Silicon nanocrystals as an enabling material for silicon Ppotonics

Silicon nanocrystals (Si-nc) is an enabling material for silicon photonics, which is no longer an emerging field of research but an available technology with the first commercial products available on the market. In this paper, properties and applications of Si-nc in silicon photonics are reviewed. After a brief history of silicon photonics, the limitations of silicon as a light emitter are discussed and the strategies to overcome them are briefly treated, with particular attention to the recent achievements. Emphasis is given to the visible optical gain properties of Si-nc and to its sensitization effect on Er ions to achieve infrared light amplification. The state of the art of Si-nc applied in a few photonic components is reviewed and discussed. The possibility to exploit Si-nc for solar cells is also presented. in addition, nonlinear optical effects, which enable fast all-optical switches, are described.

Magnetic hardening mechanisms in Nd-Fe-B nanocrystalline material

Microstructural and magnetic measurements of the evolution by heat treatment of initially amorphous Nd16Fe76B8 alloys prepared by melt spinning are presented. Evidence of magnetic hardening above a threshold temperature induced by magnetic isolation of the Nd2Fe14B grains is provided. A thermodynamic and kinetic explanation of local melting of the intergranular nanostructured Nd¿rich eutectic phase at temperatures below 900 K based on capillary effects is presented. A subsequent Ostwald ripening process moves Nd to wet intimately the hard magnetic grains, becoming, on cooling, a real paramagnetic isolating thin film (~2.5 nm). By using a simple analogy, it is shown that the switching magnetization field in a single¿domain crystal can be drastically affected through the exchange coupling to neighboring grains with different orientation of the easy axis. This effect should be important enough to reinforce the coercive field of polycrystalline hard magnetic materials and explains the observed enhancement from 0.9 to 1.9 T.

Damage spreading transition in glasses: A probe for the ruggedness of the configurational landscape

We consider damage spreading transitions in the framework of mode-coupling theory. This theory describes relaxation processes in glasses in the mean-field approximation which are known to be characterized by the presence of an exponentially large number of metastable states. For systems evolving under identical but arbitrarily correlated noises, we demonstrate that there exists a critical temperature T0 which separates two different dynamical regimes depending on whether damage spreads or not in the asymptotic long-time limit. This transition exists for generic noise correlations such that the zero damage solution is stable at high temperatures, being minimal for maximal noise correlations. Although this dynamical transition depends on the type of noise correlations, we show that the asymptotic damage has the good properties of a dynamical order parameter, such as (i) independence of the initial damage; (ii) independence of the class of initial condition; and (iii) stability of the transition in the presence of asymmetric interactions which violate detailed balance. For maximally correlated noises we suggest that damage spreading occurs due to the presence of a divergent number of saddle points (as well as metastable states) in the thermodynamic limit consequence of the ruggedness of the free-energy landscape which characterizes the glassy state. These results are then compared to extensive numerical simulations of a mean-field glass model (the Bernasconi model) with Monte Carlo heat-bath dynamics. The freedom of choosing arbitrary noise correlations for Langevin dynamics makes damage spreading an interesting tool to probe the ruggedness of the configurational landscape.

Reflexiones en torno a la cultura material. nuevas aproximaciones

Para cualquier arqueólogo, la cultura material representa la base de toda investigación ya que es la documentación prioritaria sobre la cual construye sus teorías e interpretaciones. En los últimos años, algunos antropólogos como Appadurai o Kopitoff han propuesto una nueva lectura de cómo analizar la cultura material en el ámbito de la etnografía. Algunas de sus propuestas, debidamente adaptadas, permiten una reflexión más amplia sobre el estudio de la cultura material, que proponemos aquí.