2,105 research outputs found
Corrugated velocity patterns in the spiral galaxies: NGC 278, NGC 1058, NGC 2500 & UGC 3574
We address the study of the H α vertical velocity field in a sample of four nearly face-on galaxies using long-slit spectroscopy taken with the Intermediate dispersion Spectrograph and Imaging System (ISIS), attached to the William Herschel Telescope (WHT) at the Roque de los Muchachos Observatory (Spain). The spatial structure of the velocity vertical component shows a radial corrugated pattern with spatial scales higher or within the order of 1 kpc. The gas is mainly ionized by high-energy photons: only in some locations of NGC 278 and NGC 1058 is there some evidence of ionization by low-velocity shocks, which, in the case of NGC 278, could be due to minor mergers. The behaviour of the gas in the neighbourhood of the spiral arms fits, in the majority of the observed cases, with that predicted by the so-called hydraulic bore mechanism, where a thick magnetized disc encounters a spiral density perturbation. The results obtained show that it is difficult to explain the H α large-scale velocity field without the presence of a magnetized, thick galactic disc. Larger samples and spatial covering of the galaxy discs are needed to provide further insight into this problem.We acknowledge financial support from the Spanish Ministry of Economy and Competitiveness through grants AYA2010-17631 and AYA2013-40611-P, and from the Consejeria de Educacion y Ciencia (Junta de Andalucia) through TIC-101, TIC-4075 and TIC-114Peer Reviewe
Mariano Peset, historiador de las universidades, historiador de la Universidad de México
En este trabajo analizamos a partir de las obras de Mariano Peset sobre la Universidad de México, su aportación a la historia de las universidades hispánicas
Detector for monitoring potential bleeding during electron intraoperative radiotherapy
Purpose: The aim of this work is to develop a bleeding detector integrated into the acrylic circular applicators for specific mobile linacs. Thus, a bleeding detector has been developed based on a capacitive sensor to be used with plastic applicators, as in the case of LIAC HWL from Sordina IORT Technologies SpA. According to the clinical impact, we have selected 0.5 cm as the minimum depth of fluid that should be detected. Methods: An experiment was developed using water-simulating blood. Two setups were considered: non-beveled applicators with 7 cm and 10 cm diameter. Measurements were done for applicators 0° and 45° tilted, both with respect to the horizontal surface, in order to mimic the worst clinical scenario according to the irradiation gantry and applicator bevel angle. The behavior of the detector under irradiation was analyzed and the impact of the stray radiation on the detector was also evaluated. Results: The detector was able to distinguish the presence of liquid at a minimum height of 0.5 cm. A linear behavior was obtained for both setups. We have also verified that the LIAC HWL radiation does not affect the measurements nor does the detector interfere with the stray radiation. The bleeding detector is a quasi-digital capacitive sensor with low-cost, high linearity, and easy to install. Conclusions: With this detector it is possible to perform a continuous monitoring of the liquid measurements even during the irradiation phase. Thus, it can operate not only as a pre-treatment detector but also as a continuous one
Improving bleeding detector features for electron intraoperative radiotherapy
Purpose: The aim of this work is to improve the potential bleeding detection during intraoperative radiotherapy with linac polymethyl methacrylate applicators (PMMA), based on one previously developed. The improvements carried out have been focused on: i) minimizing the impact of the detector on the visual through the plastic applicators and ii) avoiding the asymmetry in the detection capability when the applicator is tilted. Methods: Simulations have been made to select the geometry that provides a reduced visual impact on the applicator as well as allowing an independent response with the tilting angle of the applicator. A low-noise circuit for signal conditioning has been developed. Measurements have been made on three setups: 10 cm, 7 cm and 4 cm applicator diameters, 0° and 45° tilted. Results: The detector has a visibility through the applicator greater than 50%. Due to the geometry, optimal detection is ensured regardless of its orientation when the applicator is tilted. It is possible to detect the presence of fluid well below the typical perturbing fluid depth established by the clinic (1-1.5 cm). Conclusions: The detector can distinguish the presence of around 0.5 cm of fluid depth while showing a high visual field through the PMMA applicators and providing a measure that does not depend on the detector orientation when the applicator is tilted. The prototype is ready for its industrialization by embedding it into the applicator for clinical use. The detector would have a significant impact on both the quality assurance and the outcome of the treatment
La concesión de honores públicos a magistrados y decuriones en las ciudades de la Bética
In this work, we study the concession of public honours to magistrales and decurions in the Betica. We analyse the origin of this practice in Hispania, its function, the different types ofhonours actually conceded, the motivations for honorific distinctions, and the social groups participating in homage events. Finally, we try to place the honoured in their social, familiar, politic and economic context and, thus, elucidate the reasons for their citizen public homage.En este trabajo estudiamos la concesión de honores públicos a magistrados y decuriones de la Bética. Analizamos el origen de esta práctica en Hispania, su función, los diferentes tipos de honores concedidos, las motivaciones que dieron lugar a distinciones honorfficas y los grupos sociales participantes en los homenajes. Finalmente, intentamos insertar a los honrados en su contexto social, familiar, polftico y económico, lo que nos ayuda a comprender los motivos por los que éstos recibieron homenajes públicos ciudadanos
Mechanical properties of pre-stressed fabric-reinforced cementitious matrix composite (PFRCM)
© 2018. This version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Fabric Reinforced Cementitious Matrix (FRCM) is a composite strengthening material used to strengthen masonry and concrete structures in a passive way due to the requirement of crack activation. Prestressing fabric is proposed to overcome this limitation, to increase the cracking strength and to obtain a stiffer response. With this aim, over 200 tensile tests on FRCM specimens were performed to analyse the influence of prestressing fabrics. Other variables, like fixation system, testing speed, matrix material and fabric material, were also discussed. Evidences lead to conclude that prestressing fabric of FRCM is an effective way to increase its tensile cracking strength (over 30%) and tensile stiffness.Peer ReviewedPostprint (author's final draft
Straightforward Synthesis of Novel Acene-Based Aryne Precursors
Large polycyclic o-(trimethylsilyl)aryl triflates are easily obtained by reaction of commercially available bisaryne precursors with cyclopentadienones. The transformation involves controlled generation of one of the aryne functionalities, trapping by Diels–Alder reaction with a dienone, and chelotropic extrusion of CO. The newly synthesized triflates are precursors of acene-based arynes, including a didehydropentaceneFinancial support from the Spanish Ministry of Science and Competitiveness (MINECO, CTQ2013-44142-P and MAT2013-46593-C6-6-P), the European Union (Project PAMS, contract no. 610446), Xunta de Galicia (GPC2014/25), and FEDER is gratefully acknowledged. D.R.-L. thanks the Spanish Ministry of Education for the award of an FPU fellowshipS
El proyecto ParemioRom. Refranes meteorológicos y geoparemiología romance
Presentación del proyecto ParemioRom, que dirijo como IP, y que cuenta con 11 colaboradores de distintos países de Europa. Muestra de los resultados del estudio de los refranes meteorológicos de la Romania desde un punto de vista geolingüístico
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