University of Alcal

Madrid, Spain

University of Alcal

Madrid, Spain

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Prez-Rico C.,University Hospital Principe Of Asturias | Pascual G.,University of Alcal | Pascual G.,CIBER ISCIII | Sotomayor S.,University of Alcal | And 8 more authors.
American Journal of Ophthalmology | Year: 2011

Purpose To evaluate possible changes in the collagen and elastic components of the subepithelial connective tissue of human pterygium. Design Immunohistochemical study. Methods Immunohistochemical staining using antitropoelastin, anti-fibulin-2, and anti-fibulin-3 antibodies was performed in 10 normal conjunctival and 20 pterygium specimens. Masson trichome staining also was performed to study subepithelial connective tissue. Sirius red staining was used to identify collagen type I and III components. Tropoelastin, fibulin-2, and fibulin-3 messenger ribonucleic acid (mRNA) expressions were analyzed in 9 conjunctival and 12 pterygium specimens by quantitative real-time polymerase chain reaction assay. Results The subepithelial connective tissue and vessels were more predominant in pterygium compared with the normal conjunctival tissue. Amorphous subepithelial zones were observed in the areas of the pterygium tissue, but not in normal conjunctiva. Increased tropoelastin staining was seen in the pterygium tissue with areas of degenerative changes or immature formation of elastic fibers, as well an increase in tropoelastin mRNA, in contrast with fibulin-2 and fibulin-3 messenger levels. Fibulin-2 and fibulin-3 expression was colocalized in the subepithelial connective tissue and was distributed along blood and lymphatic vessels. Collagen type III, an immature form of collagen, was increased in the pathologic samples in association with a tissue remodeling process. Conclusions Elastin metabolism is dysregulated in the pathogenesis of human pterygium with tropoelastin, fibulin-2, and fibulin-3 overexpression in the subepithelial connective tissue.


Buendia R.,University of Borås | Gil-Pita R.,University of Alcal | Seoane F.,University of Borås | Seoane F.,KTH Royal Institute of Technology
Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS | Year: 2011

Applications based on measurements of Electrical Bioimpedance Spectrocopy (EBIS) analysis are proliferating. The most spread and known application of EBIS is the non-invasive assessment of body composition. Fitting to the Cole function to obtain the Cole parameters, R 0 and R, is the core of the EBIS analysis to obtain the body fluid distribution. An accurate estimation of the Cole parameters is essential for the Body Composition Assessment (BCA) and the estimation process depends on several factors. One of them is the upper frequency limit used for the estimation and the other is the number of measured frequencies in the measurement frequency range. Both of them impose requirements on the measurement hardware, influencing largely in the complexity of the bioimpedance spectrometer. In this work an analysis of the error obtained when estimating the Cole parameters with several frequency ranges and different number of frequencies has been performed. The study has been done on synthetic EBIS data obtained from experimental Total Right Side (TRS) measurements. The results suggest that accurate estimations of R 0 and R for BCA measurements can be achieved using much narrower frequency ranges and quite fewer frequencies than electrical bioimpedance spectrometers commercially available nowadays do. © 2011 IEEE.


Del Hoyo A.,University of Alcal | Alvarez R.,University of Alcal | Del Campo E.M.,University of Alcal | Gasulla F.,University of Valencia | And 2 more authors.
Annals of Botany | Year: 2011

Background and Aims: Most lichens form associations with Trebouxia phycobionts and some of them simultaneously include genetically different algal lineages. In other symbiotic systems involving algae (e.g. reef corals), the relative abundances of different endosymbiotic algal clades may change over time. This process seems to provide a mechanism allowing the organism to respond to environmental stress. A similar mechanism may operate in lichens with more than one algal lineage, likewise protecting them against environmental stresses. Here, the physiological responses to oxidative stress of two distinct Trebouxia phycobionts (provisionally named TR1 and TR9) that coexist within the lichen Ramalina farinacea were analysed. •Methods Isolated phycobionts were exposed to oxidative stress through the reactive oxygen species propagator cumene hydroperoxide (CuHP). Photosynthetic pigments and proteins, photosynthesis (through modulated chlorophyll fluorescence), the antioxidant enzymes superoxide dismutase (SOD) and glutathione reductase (GR), and the stress-related protein HSP70 were analysed. Key ResultsPhotosynthetic performance was severely impaired by CuHP in phycobionts, as indicated by decreases in the maximal PSII photochemical efficiency (Fv/F m), the quantum efficiency of PSII (ΦPSII) and the non-photochemical dissipation of energy (NPQ). However, the CuHP-dependent decay in photosynthesis was significantly more severe in TR1, which also showed a lower NPQ and a reduced ability to preserve chlorophyll a, carotenoids and D1 protein. Additionally, differences were observed in the capacities of the two phycobionts to modulate antioxidant activities and HPS70 levels when exposed to oxidative stress. In TR1, CuHP significantly diminished HSP70 and GR but did not change SOD activities. In contrast, in TR9 the levels of both antioxidant enzymes and those of HSP70 increased in response to CuHP. •Conclusions The better physiological performance of TR9 under oxidative conditions may reflect its greater capacity to undertake key metabolic adjustments, including increased non-photochemical quenching, higher antioxidant protection and the induction of repair mechanisms. © The Author 2010. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved.


del Campo E.M.,University of Alcal | Catala S.,University of Valencia | Gimeno J.,University of Valencia | del Hoyo A.,University of Alcal | And 4 more authors.
FEMS Microbiology Ecology | Year: 2013

The epiphytic lichen Ramalina farinacea is distributed throughout the northern hemisphere in which the same two algal Trebouxia species (provisionally named TR1 and TR9) coexist in every thallus. Ramalina farinacea symbionts were characterized based on the two fungal nuclear loci (nrITS and rpb2) along with the primary and secondary structures of nrITS from each Trebouxia species in the Iberian Peninsula and Canary Islands. The results indicated a noticeable genetic differentiation between mycobionts from these two geographic areas and also suggested concerted changes in the three partners of a lichen symbiosis toward two clearly distinguishable 'holobiont' lineages. Modeling of ITS2 RNA secondary structures suggested their temperature sensitivity in TR1 but not in TR9, which was consistent with the observed superior physiological performance of TR9 phycobionts under relatively high temperatures. Both TR1 and TR9 phycobionts have been also found in a variety of taxonomically distinct lichens with a preferably Mediterranean distribution, being TR1 much more widespread than TR9. Our observations support a model in which ecological diversification and speciation of lichen symbionts in different habitats could include a transient phase consisting of associations with more than one photobiont in individual thalli. Such diversification is likely to be promoted by different physiological backgrounds. © 2012 Federation of European Microbiological Societies.


Psychogiou D.,Purdue University | Gomez-Garcia R.,University of Alcal | Peroulis D.,Purdue University
IEEE Transactions on Circuits and Systems II: Express Briefs | Year: 2016

This brief focuses on the radio frequency (RF) design of novel high-quality-factor (Q) reflective-type bandstop filters (BSFs) with narrow bandwidth (BW), small physical size, and large stopband attenuation levels. They are realized by merging acoustic-wave-lumped-element resonators (AWLRs) and lumped-element impedance inverters in a single filter architecture. In this manner, deep stopband notches that correspond to resonators with effective quality factors (Qeff) on the order of 1000 are created. Furthermore, the obtained rejection bands exhibit fractional BWs that are no longer restricted by the electromechanical coupling coefficient kt2 of the constituent acoustic wave (AW) resonators as opposed to the traditional all-AW filters. Experimental prototypes of first- and third-order frequency-static BSFs were built and tested at 418 MHz to validate the proposed concept. Measured stopbands with 3-dB BWs from 0.2 to 0.5 MHz, maximum stopband attenuation in the range of 15-43 dB, and passband insertion loss between 0.37 and 1.6 dB are reported. Moreover, an electronically switchable BSF with dynamic notch allocation is presented as a practical demonstrator device for switchable RF-interference suppression. A design methodology that relates to coupled-resonator filter formalism is also addressed to facilitate the systematic theoretical synthesis of the engineered AWLR-based reflective-type BSFs. © 2004-2012 IEEE.


Boquete L.,University of Alcal | Boquete L.,HIGH-TECH | Cambralla R.,University of Alcal | Rodrguez-Ascariz J.M.,University of Alcal | And 4 more authors.
ISA Transactions | Year: 2010

This paper presents a low-cost and highly versatile temperature-monitoring system applicable to all phases of wine production, from grape cultivation through to delivery of bottled wine to the end customer. Monitoring is performed by a purpose-built electronic system comprising a digital memory that stores temperature data and a ZigBee communication system that transmits it to a Control Centre for processing and display. The system has been tested under laboratory conditions and in real-world operational applications. One of the system's advantages is that it can be applied to every phase of wine production. Moreover, with minimum modification, other variables of interest (pH, humidity, etc.) could also be monitored and the system could be applied to other similar sectors, such as olive-oil production. © 2010 ISA. Published by Elsevier Ltd. All rights reserved.


Gomez-Garcia R.,University of Alcal | Sanchez-Renedo M.,University of Alcal
IEEE Transactions on Microwave Theory and Techniques | Year: 2010

A new class of microwave dual-band bandpass planar filter is reported. It uses an original generalized branch-line hybrid topology devised here, operating as dual-passband transversal filtering section. This type of filter network, under feedforward signal-interaction concepts, enables dual-band bandpass filtering actions with transmission zeros to be generated. Some design formulas and guidelines helping to synthesize the proposed dual-passband transversal filtering section are given. Furthermore, to prove its practical viability, theoretical, simulated and experimental results of two manufactured sharp-rejection dual-band bandpass microstrip filter prototypes are shown. © 2010 IEEE.


Algar M.J.,University of Alcal | Lozano L.,University of Alcal | Diego I.G.,University of Alcal | Catedra F.,University of Alcal
Proceedings of the 5th European Conference on Antennas and Propagation, EUCAP 2011 | Year: 2011

This paper presents an extended study of the analysis of the Doppler shift by wind turbines. Two different situations have been considered. The first one is a simple case in which the geomety is compoused by five cubes. The second one analyzes the Doppler shift generated by the rotating blades of a wind turbine. These studies have been performed applying asymptotic and rigorous methods that are implemented into the new computer tool, named NEWFASANT. The results obtained by FASANT module, implements asymptotic method, and by MONURBS module, implements rigorous method, have been compared. © 2011 EurAAP.


Tayebi A.,University of Alcal | Gomez Perez J.,University of Alcal | Gonzalez Diego I.,University of Alcal | Catedra F.,University of Alcal
Proceedings of the 5th European Conference on Antennas and Propagation, EUCAP 2011 | Year: 2011

This work presents the implementation of Boolean operations such as the intersection and subtraction of closed or open of bodies defined by NURBS. The developed code is able to process any arbitrary structure with small geometrical details. Normally, commercial solvers provide resulting objects composed by flat facets (rectangles or triangles) as a result of the Boolean operation. Thus, the result of the Boolean operation does not fit accurately the shape of the original objects. Our implementation is able to give accurate trimmed surfaces that perfectly fit the real shape of the original objects since the Boolean function provides a structure formed by several curved surfaces. The proposed approach is explained and some examples are shown to validate the performance of the code. © 2011 EurAAP.

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