Novetats

Ship-weather routing applied to short sea distances: study of the feasibility of SIMROUTEv2 algorithm

UPCommons - Lun, 12/11/2017 - 18:29
Ship-weather routing applied to short sea distances: study of the feasibility of SIMROUTEv2 algorithm Basiana Ribera, Lluís; Castells Sanabra, Marcel·la; Grifoll Colls, Manel; Martínez de Osés, Francesc Xavier; Borén Altés, Clara
Categorías: Novetats

El rol del confort térmico en la política de la eficiencia energética: la mejora de la calidad de vida como motor del cambio: caso de estudio: Calle Pirineus, Santa Coloma de Gramenet

UPCommons - Lun, 12/11/2017 - 18:26
El rol del confort térmico en la política de la eficiencia energética: la mejora de la calidad de vida como motor del cambio: caso de estudio: Calle Pirineus, Santa Coloma de Gramenet Barón Rodríguez, Alan Màster universitari en Estudis Avançats en Arquitectura: Gestió i Valoració Urbana i Arquitectònica
Categorías: Novetats

Centrality measure in social networks based on linear threshold model

UPCommons - Lun, 12/11/2017 - 17:58
Centrality measure in social networks based on linear threshold model Riquelme Csori, Fabián; Gonzalez Cantergiani, Pablo; Molinero Albareda, Xavier; Serna Iglesias, María José Centrality and influence spread are two of the most studied concepts in social network analysis. In recent years, centrality measures have attracted the attention of many researchers, generating a large and varied number of new studies about social network analysis and its applications. However, as far as we know, traditional models of influence spread have not yet been exhaustively used to define centrality measures according to the influence criteria. Most of the considered work in this topic is based on the independent cascade model. In this paper we explore the possibilities of the linear threshold model for the definition of centrality measures to be used on weighted and labeled social networks. We propose a new centrality measure to rank the users of the network, the Linear Threshold Rank (LTR), and a centralization measure to determine to what extent the entire network has a centralized structure, the Linear Threshold Centralization (LTC). We appraise the viability of the approach through several case studies. We consider four different social networks to compare our new measures with two centrality measures based on relevance criteria and another centrality measure based on the independent cascade model. Our results show that our measures are useful for ranking actors and networks in a distinguishable way.
Categorías: Novetats

Synaptic phosphorylated a-synuclein in dementia with Lewy bodies

UPCommons - Lun, 12/11/2017 - 17:49
Synaptic phosphorylated a-synuclein in dementia with Lewy bodies Colom-Cadena, Martí; Pegueroles, Jordi; Herrmann, Abigail G.; Henstridge, Christopher M.; Muñoz, Laia; Querol-Vilaseca, Marta; San Martin, Carla; Luque-Cabecerans, Joan; Clarimon, Jordi; Belbin, Olivia; Nuñez-Llaves, Raúl; Blesa, Rafael; Smith, Colin; McKenzie, Chris-Anne; Frosch, Matthew P.; Roe, Allyson; Fortea, Juan; Andilla, Jordi; Loza-Alvarez, Pablo; Gelpi, Ellen; Hyman, Bradley T.; Spires-Jone, Tara L.; Lleó, Alberto Dementia with Lewy bodies is characterized by the accumulation of Lewy bodies and Lewy neurites in the CNS, both of which are composed mainly of aggregated a-synuclein phosphorylated at Ser129. Although phosphorylated a-synuclein is believed to exert toxic effects at the synapse in dementia with Lewy bodies and other a-synucleinopathies, direct evidence for the precise synaptic localization has been difficult to achieve due to the lack of adequate optical microscopic resolution to study human synapses. In the present study we applied array tomography, a microscopy technique that combines ultrathin sectioning of tissue with immunofluorescence allowing precise identification of small structures, to quantitatively investigate the synaptic phosphorylated a-synuclein pathology in dementia with Lewy bodies. We performed array tomography on human brain samples from five patients with dementia with Lewy bodies, five patients with Alzheimer’s disease and five healthy control subjects to analyse the presence of phosphorylated a-synuclein immunoreactivity at the synapse and their relationship with synapse size. Main analyses were performed in blocks from cingulate cortex and confirmed in blocks from the striatum of cases with dementia with Lewy bodies. A total of 1 318 700 single pre- or post-synaptic terminals were analysed. We found that phosphorylated a-synuclein is present exclusively in dementia with Lewy bodies cases, where it can be identified in the form of Lewy bodies, Lewy neurites and small aggregates (50.16 mm3). Between 19% and 25% of phosphorylated a-synuclein deposits were found in presynaptic terminals mainly in the form of small aggregates. Synaptic terminals that co-localized with small aggregates of phosphorylated a-synuclein were significantly larger than those that did not. Finally, a gradient of phosphorylated a-synuclein aggregation in synapses (pre4pre + post4post-synaptic) was observed. These results indicate that phosphorylated a-synuclein is found at the presynaptic terminals of dementia with Lewy bodies cases mainly in the form of small phosphorylated a-synuclein aggregates that are associated with changes in synaptic morphology. Overall, our data support the notion that pathological phosphorylated a-synuclein may disrupt the structure and function of the synapse in dementia with Lewy bodies.
Categorías: Novetats

A first estimate for a pressure-retarded osmosis-driven thermosyphon

UPCommons - Jue, 12/07/2017 - 16:29
A first estimate for a pressure-retarded osmosis-driven thermosyphon Arias Montenegro, Francisco Javier Pressure retarded osmosis (PRO) process and its significance for thermosyphon technology is discussed. In previous work the possibility to drive a thermosyphon by difference of densities from induced salinity gradients from evaporation at solar collectors with downward heat transfer was assessed. Nevertheless it was concluded that large evaporative areas or dilution with volatile compounds was mandatory. In this work it is shown that by taking advantage of the energy released during the spontaneous mixing of the low-concentration evaporative fraction and the high-salinity of the no-evaporated fraction which is generally referred as pressure-retarded osmosis (PRO) process, then the thermosyphon can runs with downward heat transfer (hot fluid flows down and cold fluid rises up) and using an evaporative surface area much more smaller and then eliminating the need for dilution with high volatile compounds. © 2017. This version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
Categorías: Novetats

La reacción anti-tecnológica

UPCommons - Jue, 12/07/2017 - 11:54
La reacción anti-tecnológica Barceló García, Miquel
Categorías: Novetats

Los informáticos que hacen falta

UPCommons - Jue, 12/07/2017 - 11:39
Los informáticos que hacen falta Barceló García, Miquel
Categorías: Novetats

Monitoring of an external prestressing used as a strengthening technique in a historical masonry steeple

UPCommons - Jue, 12/07/2017 - 11:27
Monitoring of an external prestressing used as a strengthening technique in a historical masonry steeple Llorens, Miquel; Señís López, Roger; Moreno, Benjamí; Pavón García, Susana The Sacred Heart Church of Vistabella (La Secuita, Spain) was designed by Josep Maria Jujol and built in the early twenties of the XX century. The slenderness of its steeple makes it extremely exposed to wind action, to the extent that its stability has been threatened since the construction started. At the end of 1934, the upper spire crumbled away, being rebuilt and reinforced with steel passive bars. After some numerical approaches, it became clear that the lightness of such a masonry construction along with the feebleness of the connections between the structural members were at the basis of the problem. In order to provide additional vertical load without substantively modifying the structural scheme, a solution based on external prestressed bars, was implemented. The bars replace the existing passive bars, which have proven to be totally useless. The active system proposed allows to eliminate the masonry’s tensile stresses under the action of the wind. The additional loading to be applied varies depending on the level (three levels in total), according to the gradual post-tensioning system proposed as a strengthening technique of the steeple. Therefore, it has been necessary to design a procedure able to introduce independent tensions at the different levels throughout the same tie and the corresponding monitoring system to control the tensioning process during the implementation. The procedure, the theory that supports it, and the results of the follow-up are described in detail, these being the objective of the paper.
Categorías: Novetats

ERP, ¿El mal inevitable?

UPCommons - Jue, 12/07/2017 - 11:24
ERP, ¿El mal inevitable? Barceló García, Miquel
Categorías: Novetats

Perplejidad ante la nueva economía

UPCommons - Jue, 12/07/2017 - 11:07
Perplejidad ante la nueva economía Barceló García, Miquel
Categorías: Novetats

Bioinformática

UPCommons - Jue, 12/07/2017 - 10:44
Bioinformática Barceló García, Miquel
Categorías: Novetats

El ordenador que desaparece

UPCommons - Jue, 12/07/2017 - 10:36
El ordenador que desaparece Barceló García, Miquel
Categorías: Novetats

Ordenadores de ADN

UPCommons - Jue, 12/07/2017 - 10:27
Ordenadores de ADN Barceló García, Miquel
Categorías: Novetats

Structural analysis and damage assessment of the Vistabella Church’s Tower to establish the masonry’s active reinforcement for its restoration

UPCommons - Jue, 12/07/2017 - 10:20
Structural analysis and damage assessment of the Vistabella Church’s Tower to establish the masonry’s active reinforcement for its restoration Señís López, Roger; Pavón García, Susana This paper presents the reinforcement system for the restoration of the Vistabella Church’s Tower (La Secuita, Tarragona). The intervention was carried out due to evident chronic pathologies that affected the resistant behaviour and stability of the steeple. After some numerical approaches (structural analysis and damage assessment) it became clear that, in relation the wind action, the lightness of such a masonry construction along with the feebleness of the connections between the structural members were at the basis of the problem. In order to provide additional vertical load without substantively modifying the structural scheme, a solution based on external prestressed bars, was implemented. The procedure, the theory that supports it and the results of the follow-up are described in detail, these being the objective of the paper.
Categorías: Novetats

COST TU1406: an overview of European standardization on quality control of road bridges

UPCommons - Mar, 12/05/2017 - 20:16
COST TU1406: an overview of European standardization on quality control of road bridges Matos, Jose C.; Casas Rius, Joan Ramon Road asset management is a task of great responsibility, since it involves vital assets to the community. An efficient transportation network is essential for the modern society from the economic, societal and environmental point of view. Today, it is a challenge for operators to manage road infrastructures under their responsibility in an efficient way, meeting the present and future needs of the community they serve. For this purpose, authorities need to produce an asset management plan which should not only define the goals to be achieved by exploiting the roadway bridge network, but that should also identify the investment needs and priorities based on a life cycle cost criteria. In addition, a proper condition assessment of these assets must be conducted to support the decision-making process regarding their preservation.
Categorías: Novetats

Performance assessment of embedded distributed optical fiber sensors in reinforced concrete structures

UPCommons - Mar, 12/05/2017 - 20:10
Performance assessment of embedded distributed optical fiber sensors in reinforced concrete structures Barrias, Antonio Jose de Sousa; Casas Rius, Joan Ramon; Villalba Herrero, Sergi In this paper, an experiment where distributed optical fiber sensors (DOFS) were implemented in two small concrete beams subjected to a three-point load test is outlined. Here, an optical backscatter reflectometry based DOFS is implemented simultaneously embedded in the concrete (glued to the steel rebar) and attached to the outer surface of the concrete after its hardening. For comparison purposes, three electrical strain gauges are also used in the rebar. The main objectives with this experiment, is to analyze the feasibility of installation of DOFS directly on the rebar element of a reinforced concrete beam and compare the measured strain at rebar and surface of the concrete.
Categorías: Novetats

A new model to analyze corrugated steel web bridges

UPCommons - Mar, 12/05/2017 - 19:15
A new model to analyze corrugated steel web bridges Lei, Jun; Xu, Dong; Turmo Coderque, José The wide application of corrugated steel web bridges has led to a rising demand on accurate tools to analyze this type of structures. Current computational models for these analyses are mainly related to those models using 2D (or 3D) beam elements, solid (shell) elements. Despite the modelling simplicity, beam models can predict the overall structural behavior but failed to provide a refined response on local areas. On the other hand, the elaborated models are better at capturing the local response. However, they are faced with computation and convergence difficulties. To fill this gap, this paper investigates a new model to analyze the structural behavior of corrugated steel web bridges. In this model, the concrete slabs and corrugated steel webs are simulated by the grid composed of 3D beam elements. Specially, the folding effects of the webs are simulated by modifying the mechanical parameters of the longitudinal elements in the grids of beams. The performance of the model is studied by comparing the results from it and those from solid models. These comparisons include the vertical deflections in the longitudinal direction and the vertical deflections in the transverse direction at midspan and one-fourth point of the span. In addition, the normal stresses and the shear stresses due to different loadings are investigated. The results indicate the accuracy and the applicability of this new model to analyze the corrugated steel web bridge.
Categorías: Novetats

Condition assessment using structural system identification

UPCommons - Mar, 12/05/2017 - 19:02
Condition assessment using structural system identification Lei, Jun; Lozano-Galant, José Antonio; Nogal Macho, María; Xu, Dong; Turmo Coderque, José The accumulation of progressive deterioration of structures might lead to the failure of structures. In order to avoid potential accidents, it is important to carry out condition assessment using structural system identification. This is based on the assumption that damage of structures can be reflected in the change of parameters. In every SSI method, measurement errors are introduced in the process of data collection and simulation errors also exist due to the inherent property of the algorithm used. The observability method has been proposed to deal with structural system identification under static loadings. Up to now, error analysis for this method has not been addressed yet. To fill this gap, this paper evaluate the effects of measurement errors and simulation errors on the observability method. The effects of measurement errors in a specific measurement and in all measurements are considered. The result indicate that the loading case and the location of the measrement is of primary importance. Also, rotations are less sensitive to errors than vertical deflections. On the other hand, the error propogation during the identification regarding the recursive steps and the curvature of structure is also illustrated.
Categorías: Novetats

Optical label-free nanoplasmonic biosensing using a vertical-cavity surface-emitting laser and charge-coupled device

UPCommons - Mar, 12/05/2017 - 18:49
Optical label-free nanoplasmonic biosensing using a vertical-cavity surface-emitting laser and charge-coupled device Hedsten, Karin; Fonollosa Magrinyà, Jordi; Enoksson, Peter; Modh, Peter; Bengtsson, Jörgen; Sutherland, Duncan; Dmitriev, Alexander
Categorías: Novetats

Quality coding by neural populations in the early olfactory pathway: analysis using information theory and lessons for artificial olfactory systems

UPCommons - Mar, 12/05/2017 - 18:44
Quality coding by neural populations in the early olfactory pathway: analysis using information theory and lessons for artificial olfactory systems Fonollosa Magrinyà, Jordi; Gutiérrez-Gálvez, Agustín; Marco, Santiago
Categorías: Novetats

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