25 research outputs found
Interfaz de usuario para saturación de lípidos en resonancia magnética espectroscópica del cerebro humano
El objetivo de este proyecto es ofrecer a un operador cualificado de escáneres
por resonancia magnética una herramienta para el cálculo de bandas de saturación de
lípidos para imágenes espectroscópicas. Esta herramienta intenta eliminar el tedioso
trabajo de calcular las bandas de forma manual, en lo que un operador altamente
cualificado puede tardar más de dos horas. Nuestra intención es reducir este tiempo y
facilitar el cálculoIngeniería de Telecomunicació
Reducing the Dimensionality of 6-D MoM Integrals Applying Twice the Divergence Theorem
In this paper we propose a scheme for evaluating the 6-D interaction integrals appearing in volume integral equation solved with the Method of Moments and tetrahedral elements. We treat as a whole the double volume integral, applying the divergence theorem first on the source domain and then on the test domain. With the proper variable transformation and reordering, the 6-D integrals are expressed as two radial integrals plus four linear integrals over the source and observation domain planes
Comparison of surface integral equations for left-handed materials
A wide analysis of left-handed material (LHM) spheres with di®erent constitutive parameters has been carried out employ- ing di®erent integral-equation formulations based on the Method of Moments. The study is focused on the accuracy assessment of for- mulations combining normal equations (combined normal formula- tion, CNF), tangential equations (combined tangential formulation, CTF, and Poggio-Miller-Chang-Harrington-Wu-Tsai formulation, PM- CHWT) and both of them (electric and magnetic current combined ¯eld integral equation, JMCFIE) when dealing with LHM's. Relevant and informative features as the condition number, the eigenvalues dis- tribution and the iterative response are analyzed. The obtained results show up the suitability of the JMCFIE for this kind of analysis in con- trast with the unreliable behavior of the other approaches.Ministerio de Ciencia e Innovación | Ref. TEC2008-06714-C02-01Ministerio de Ciencia e Innovación | Ref. TEC2008-06714-C02-02Ministerio de Ciencia e Innovación | Ref. CSD2008-00068Xunta de Galicia | Ref. INCITE08PXIB322250P
Solution of large-scale plasmonic problems with the multilevel fast multipole algorithm
A surface integral equation together with the multilevel fast multipole algorithm is successfully applied to fast and accurate resolution of plasmonic problems involving a large number of unknowns. The absorption, scattering, and extinction efficiencies of several plasmonic gold spheres of increasing size are efficiently obtained solving the elec- tric andmagnetic current combined-field integral equation. The numerical predictions are compared with reference analytic results to demonstrate the accuracy, suitability, and capabilities of this approach when dealing with large-scale plasmonic problems
Microwave imaging technology for in-line food contamination monitoring
Foreign body contamination in food is one of the major sources of complaints against food manufacturers, and it can lead to injury, loss of brand loyalty and large recall expenses. Different technologies, such as X-ray or infrared techniques, are currently applied to detection systems used for food inspection, but physical contamination, with e.g. wood, plastic, metal and glass fragments, is still present in food. For this reason, there is the interest to develop new technologies able to address the still unmet needs of food industry. In this paper, we report about preliminary investigations of the use of the microwave imaging technology for food contamination monitoring. Numerical results show the feasibility of the proposed approach. The realization of prototype measurement system is under development
Multilayer homogeneous dielectric filler for electromagnetic invisibility
En los últimos años, la invisibilidad se ha convertido en un área de investigación de creciente interés debido a los avances en la ingeniería de materiales. Puede ser posible lograr la invisibilidad a través de dispositivos de camuflaje, recubriendo el cuerpo con una o más capas de materiales con las propiedades electromagnéticas adecuadas. Mediante el uso de técnicas asociadas al camuflaje plasmónico es posible obtener también la invisibilidad de pequeños objetos con varias capas de materiales homogéneos que trabajan desde el interior del objeto. Demostramos numéricamente que es, por lo tanto, posible lograr la invisibilidad a través de un sistema interno basado en técnicas de cancelación de la dispersión.In recent years, invisibility has become a research area of increasing interest due to the advances in material engineering. It may be possible to achieve invisibility through cloaking devices by coating the body using one or more layers of materials with the proper electromagnetic properties. By using techniques associated to plasmonic cloaking it is maybe possible to obtain also invisibility for small objects with several layers of homogeneous materials working from inside the object. We demonstrate numerically that it is, therefore, possible to achieve invisibility through an inner system based on scattering cancellation techniques.• Gobierno de España y Fondos Europeos de Desarrollo Regional. Proyecto TEC2017-85376-C2-X-R (I+D+i)
• Ministerio de Educación, Cultura y Deportes. Proyecto FPU 00022/15peerReviewe
Comparison of surface integral equation formulations for electromagnetic analysis of plasmonic nanoscatterers
The performance of most widespread surface integral equation (SIE) formulations with the method of moments (MoM) are studied in the context of plasmonic materials. Although not yet widespread in optics, SIE-MoM approaches bring important advantages for the rigorous analysis of penetrable plasmonic bodies. Criteria such as accuracy in near and far field calculations, iterative convergence and reliability are addressed to assess the suitability of these formulations in the field of plasmonics.Ministerio de Ciencia e Innovación | Ref. TEC2011-28784-C02-01Ministerio de Ciencia e Innovación | Ref. TEC2011-28784-C02-0
Pictogram Evaluation Process: Andalusian Accessible Signage Catalogue
Todas las personas necesitan apoyarse en elementos del contexto para desenvolverse por los entornos de manera autónoma. Esta necesidad se concreta en apoyos específicos cuando las personas tienen dificultades en comprensión permanentes o circunstanciales. Para que un contexto sea accesible universal y cognitivamente se emplean pictogramas para identificar los entornos. Estos pictogramas constituyen una señalética que debe ser validada por procesos estandarizados como describe la Normativa ISO-9186. El objetivo del estudio fue ampliar la base de pictogramas disponibles para la señalización de edificios y evaluar su diseño accesible. Los datos se recogieron por entrevista online y por formulario autocompletado online, en dos fases, la evaluación de la comprensibilidad y la translucidez, así como la calidad perceptual de los pictogramas. Un total de 1462 personas evaluaron la comprensión de los pictogramas y 270 su calidad perceptiva. Dicha muestra incluye participantes de diferentes colectivos y perfiles cognitivos. Se evaluaron 151 pictogramas y fueron 55 los seleccionados por cumplir criterios de comprensión, translucidez y calidad perceptiva. Este resultado supone una contribución relevante a las bases de pictogramas de uso público y privado existentes y aporta recursos señaléticos validados que pueden beneficiar a todas las personas facilitando la accesibilidad cognitiva en los espacios.Everyone needs to rely on elements in their context to move around their own environment with independence. People with permanent or temporary comprehension difficulties need specific support to be able to do so. Pictograms are some of the supports that can render a context cognitively and universally accessible. They are signs which need to be validated using standardized norms such as ISO 9186. This study aimed to increase the number of pictograms available for signposting buildings, and to evaluate their accessibility. Data were collected both via online interviews and self-administered questionnaires, in two phases: assessment of comprehensibility and translucency, and perceptual quality. A total of 1462 participants assessed the pictograms’ comprehension and 270 evaluated their perceptual quality. The sample included individuals of different groups and cognitive profiles. One hundred and fifty one pictograms were evaluated and 55 were selected after fulfilling comprehension, translucency, and perceptual quality criteria. The study is a relevant contribution to the database of pictograms available for use in private and public buildings and provides a group of validated signs that can benefit everyone by facilitating cognitive accessibility in spatial environments
A Proposed Approach to Chronic Airway Disease (CAD) Using Therapeutic Goals and Treatable Traits: A Look to the Future
© 2020 Pérez de Llano et al.Chronic airflow obstruction affects a wide range of airway diseases, the most frequent of which are asthma, COPD, and bronchiectasis; they are clearly identifiable in their extremes, but quite frequently overlap in some of their pathophysiological and clinical characteristics. This has generated the description of new mixed or overlapping disease phenotypes with no clear biological grounds. In this special article, a group of experts provides their perspective and proposes approaching the treatment of chronic airway disease (CAD) through the identification of a series of therapeutic goals (TG) linked to treatable traits (TT) – understood as clinical, physiological, or biological characteristics that are quantifiable using biomarkers. This therapeutic approach needs validating in a clinical trial with the strategy of identification of TG and treatment according to TT for each patient independently of their prior diagnosis
Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19
Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe