Polytechnic University of Valencia

About: Polytechnic University of Valencia is a education organization based out in Valencia, Spain. It is known for research contribution in the topics: Catalysis & Population. The organization has 16282 authors who have published 40162 publications receiving 850234 citations.

Nanostructured polymeric coatings based on chitosan and dopamine-modified hyaluronic acid for biomedical applications.

Abstract: In a marine environment, specific proteins are secreted by mussels and used as a bioglue to stick to a surface. These mussel proteins present an unusual amino acid 3,4-dihydroxyphenylalanine (known as DOPA). The outstanding adhesive properties of these materials in the sea harsh conditions have been attributed to the presence of the catechol groups present in DOPA. Inspired by the structure and composition of these adhesive proteins, dopamine-modified hyaluronic acid (HA-DN) prepared by carbodiimide chemistry is used to form thin and surface-adherent dopamine films. This conjugate was characterized by distinct techniques, such as nuclear magnetic resonance and ultraviolet spectrophotometry. Multilayer films are developed based on chitosan and HA-DN to form polymeric coatings using the layer-by-layer methodology. The nanostructured films formation is monitored by quartz crystal microbalance. The film surface is characterized by atomic force microscopy and scanning electron microscopy. Water contact angle measurements are also conducted. The adhesion properties are analyzed showing that the nanostructured films with dopamine promote an improved adhesion. In vitro tests show an enhanced cell adhesion, proliferation and viability for the biomimetic films with catechol groups, demonstrating their potential to be used in distinct biomedical applications.

Application of the phasor transform for automatic delineation of single-lead ECG fiducial points.

Abstract: This work introduces a new single-lead ECG delineator based on phasor transform. The method is characterized by its robustness, low computational cost and mathematical simplicity. It converts each instantaneous ECG sample into a phasor, and can precisely manage P and T waves, which are of notably lower amplitude than the QRS complex. The method has been validated making use of synthesized and real ECG sets, including the MIT-BIH arrhythmia, QT, European ST-T and TWA Challenge 2008 databases. Experiments with the synthesized recordings reported precise detection and delineation performances in a wide variety of ECGs, with signal-to-noise ratios of 10 dB and above. For real ECGs, the QRS detection was characterized by an average sensitivity of 99.81% and positive predictivity of 99.89%, for all the analyzed databases (more than one million beats). Regarding delineation, the maximum localization error between automatic and manual annotations was lower than 6 ms and its standard deviation was in agreement with the accepted tolerances for expert physicians in the onset and offset identification for QRS, P and T waves. Furthermore, after revising and reannotating some ECG recordings by expert cardiologists, the delineation error decreased notably, becoming lower than 3.5 ms, on average, and reducing by a half its standard deviation. This new proposed strategy outperforms the results provided by other well-known delineation algorithms and, moreover, presents a notably lower computational cost.

Efficient interconnects for clustered microarchitectures

Abstract: Clustering is an effective microarchitectural technique for reducing the impact of wire delays, the complexity, and the power requirements of microprocessors. In this work, we investigate the design of on-chip interconnection networks for clustered microarchitectures. This new class of interconnects has different demands and characteristics than traditional multiprocessor networks. In a clustered microarchitecture, a low inter-cluster communication latency is essential for high performance. We propose point-to-point interconnects together with an effective latency-aware instruction steering scheme and show that they achieve much better performance than bus-based interconnects. The results show that the connectivity of the network together with latency-aware steering schemes are key for high performance. We also show that these interconnects can be built with simple hardware and achieve a performance close to that of an idealized contention-free model.

Review of anti-islanding techniques in distributed generators

Abstract: This work was supported by the Spanish Ministry of Science and Innovation under Grants ENE2006-15521-C03-02 and ENE2009-13998-C02-02.