Evaluación del comportamiento de clones de teca en Costa Rica

Gramage Espí, C. (2010). Evaluación del comportamiento de clones de teca en Costa Rica. Universitat Politècnica de València. http://hdl.handle.net/10251/9095Archivo delegad

Simultaneous imaging of hard and soft biological tissues in a low-field dental MRI scanner

[EN] Magnetic Resonance Imaging (MRI) of hard biological tissues is challenging due to the fleeting lifetime and low strength of their response to resonant stimuli, especially at low magnetic fields. Consequently, the impact of MRI on some medical applications, such as dentistry, continues to be limited. Here, we present three-dimensional reconstructions of ex-vivo human teeth, as well as a rabbit head and part of a cow femur, all obtained at a field strength of 260 mT. These images are the first featuring soft and hard tissues simultaneously at sub-Tesla fields, and they have been acquired in a home-made, special-purpose, pre-medical MRI scanner designed with the goal of demonstrating dental imaging at low field settings. We encode spatial information with two pulse sequences: Pointwise-Encoding Time reduction with Radial Acquisition and a new sequence we have called Double Radial Non-Stop Spin Echo, which we find to perform better than the former. For image reconstruction we employ Algebraic Reconstruction Techniques (ART) as well as standard Fourier methods. An analysis of the resulting images shows that ART reconstructions exhibit a higher signal-to-noise ratio with a more homogeneous noise distribution.We thank anonymous donors for their tooth samples, Andrew Webb and Thomas O'Reilly (LUMC) for discussions on hardware and pulse sequences, and Antonio Tristan (UVa) for information on reconstruction techniques. This work was supported by the European Commission under Grants 737180 (FET-OPEN: HISTO-MRI) and 481 (ATTRACT: DentMRI). Action co-financed by the European Union through the Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of the Comunitat Valenciana 2014-2020 (IDIFEDER/2018/022). Santiago Aja-Fernandez acknowledges Ministerio de Ciencia e Innovacion of Spain for research grant RTI2018-094569-B-I00.Algarín-Guisado, JM.; Díaz-Caballero, E.; Borreguero-Morata, J.; Galve, F.; Grau-Ruiz, D.; Rigla, JP.; Bosch-Esteve, R.... (2020). Simultaneous imaging of hard and soft biological tissues in a low-field dental MRI scanner. Scientific Reports. 10(1):1-14. https://doi.org/10.1038/s41598-020-78456-2S114101Haacke, E. M. et al. Magnetic Resonance Imaging: Physical Principles and Sequence Design Vol. 82 (Wiley-liss, New York, 1999).Bercovich, E. & Javitt, M. C. Medical imaging: from roentgen to the digital revolution, and beyond. Rambam Maimonides Med. J. 9, e0034. https://doi.org/10.5041/rmmj.10355 (2018).Mastrogiacomo, S., Dou, W., Jansen, J. A. & Walboomers, X. F. Magnetic resonance imaging of hard tissues and hard tissue engineered bio-substitutes. Mol. Imag. Biol. 21, 1003–1019. https://doi.org/10.1007/s11307-019-01345-2 (2019).Duer, M. J. 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Instalación eléctrica en baja tensión y centro de transformación para industria dedicada a la fabricación de parachoques de automóvil por inyección de plástico

El objeto del presente Trabajo fin de Grado de Ingeniería Eléctrica es la realización de un proyecto que refleje el diseño de todos los componentes que constituyen la instalación eléctrica en baja tensión y su centro de transformación de energía eléctrica de una Industria dedicada a la fabricación de parachoques para vehículos por inyección de plástico. Por lo tanto se realizará un documento cumpliendo con el contenido mínimo de índice de proyecto para su posterior legalización ante los organismos competentes, tal como exigen los mismos, a fin de obtener la aprobación del Servicio Territorial de Industria y Energía de Valencia para su posterior conexión a las redes de la empresa suministradora de energía. Este diseño ha sido creado, contando con la base legal que exige la normativa teniendo en cuenta el Reglamento Electrotécnico para Baja Tensión y sus Instrucciones Técnicas Complementarias ITC-BT 01 a ITC-BT-51 aprobado por el Real Decreto 842/2002 de 2 de Agosto. También se ha tenido en cuenta las Normas Particulares de la Empresa Suministradora Iberdrola S.A., así como la Ordenanza General de Higiene y Seguridad en el Trabajo y las Condiciones impuestas por las entidades públicas afectadas.Más Gramage, JC. (2014). Instalación eléctrica en baja tensión y centro de transformación para industria dedicada a la fabricación de parachoques de automóvil por inyección de plástico. Universitat Politècnica de València. http://hdl.handle.net/10251/57463Archivo delegad

Visualizing composite knowledge in emergency responses using spatial hypertext

[EN] Having the right information at the right time is crucial to make decisions during emergency response. To fulfill this requirement, emergency management systems must provide emergency managers with knowledge management and visualization tools. The goal is twofold: on one hand, to organize knowledge coming from different sources, mainly the emergency response plans (the formal knowledge) and the information extracted from the emergency development (the contextual knowledge), and on the other hand, to enable effective access to information. Formal and contextual knowledge sets are mostly disjoint; however, there are cases in which a formal knowledge piece may be updated with some contextual information, constituting composite knowledge. In this paper, the authors extend a knowledge framework with the notion of composite knowledge, and use spatial hypertext to visualize this type of knowledge. The authors illustrate the proposal with a case study on accessing to information during an emergency response in an underground transportation system.A preliminary version of this paper was presented at the 7th Intemational Conference on Information Systems for Crisis Response and Management (ISCRAM 201 O), held from May 2 to 5, 2010 in Seattle, WA (USA). The work of J. H. Canós, M. C. Penadés and M. Llavador is partially funded by the Spanish Ministerio de Ciencia y Tecnología (MICINN) underprojects DEEPEN (TIN2009-08084) and TlPEx (TIN2010-19859-C03-03). The work of C. Solis is funded by Science Foundation Ireland, grant 03/CE2/1303_1, to LERO. The workofM. R S. Bruges is partially supported by grantsNo. 304252/2008-5 and480461/2009-0, respectively, from CNPq (Brazil). The work of A. S.Vivacquais partially supportedby FAPERJ (Brazil).M. Llavadorwas theholderoftheMECFPU grant no. AP2005-3356. The cooperation between the Brazilian and the Spanish research groups was partially sponsored by the CAPES/MECD Cooperation Program, Project #169/PHB2007-0064-PC.Canos Cerda, JH.; Penadés Gramage, MC.; Solís Pineda, C.; Borges, MRS.; Vivacqua, AS.; Llavador Campos, M. (2011). Visualizing composite knowledge in emergency responses using spatial hypertext. International Journal of Information Systems for Crisis Response and Management. 3(3):52-65. https://doi.org/10.4018/jiscrm.2011070104S52653

Magneto-stimulation limits in medical imaging applications with rapid field dynamics

[EN] Objective. The goal of this work is to extend previous peripheral nerve stimulation (PNS) studies to scenarios relevant to magnetic particle imaging (MPI) and low-field magnetic resonance imaging (MRI), where field dynamics can evolve at kilo-hertz frequencies. Approach. We have constructed an apparatus for PNS threshold determination on a subject's limb, capable of narrow and broad-band magnetic stimulation with pulse characteristic times down to 40 mu s. Main result. From a first set of measurements on 51 volunteers, we conclude that the PNS dependence on pulse frequency/rise-time is compatible with traditional stimulation models where nervous responses are characterized by a rheobase and a chronaxie. Additionally, we have extended pulse length studies to these fast timescales and confirm thresholds increase significantly as trains transition from tens to a few pulses. We also look at the influence of field spatial distribution on PNS effects, and find that thresholds are higher in an approximately linearly inhomogeneous field (relevant to MRI) than in a rather homogeneous distribution (as in MPI). Significance. PNS constrains the clinical performance of MRI and MPI systems. Extensive magneto-stimulation studies have been carried out recently in the field of MPI, where typical operation frequencies range from single to tens of kilo-hertz. However, PNS literature is scarce for MRI in this fast regime, relevant to small (low inductance) dedicated MRI setups, and where the resonant character of MPI coils prevents studies of broad-band stimulation pulses. This work advances in this direction.We thank all 51 anonymous volunteers for their participation in these studies, and Manuel Murbach for discussions. This work was supported by the European Commission under grant 737 180 (FET-Open: HistoMRI) and Ministerio de Ciencia e Innovacion of Spain for research grant PID2019-111436RB-C21. Action co-financed by the European Union through the Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of the Comunitat Valenciana 2014-2020 (IDIFEDER/2018/022)Grau-Ruiz, D.; Rigla, JP.; Pallás Lodeiro, E.; Algarín-Guisado, JM.; Borreguero-Morata, J.; Bosch-Esteve, R.; López-Comazzi, G.... (2022). Magneto-stimulation limits in medical imaging applications with rapid field dynamics. Physics in Medicine and Biology. 67(4):1-14. https://doi.org/10.1088/1361-6560/ac515c11467