314 research outputs found

    Medición del ángulo Q mediante goniometría convencional y videofotogrametría en 3D. Correlación de los resultados

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    Este trabajo pretende demostrar la existencia de correlación entre la medición del ángulo Q estático mediante goniometría convencional y mediante videofotogrametría en 3D, para que en próximos estudios se pueda obviar la exploración previa por el método convencional

    Laparoscopic image analysis for automatic tracking of surgical tools

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    Laparoscopy is a surgical technique nowadays embedded in the clinical routine. Recent researches have been focused on analysing video information captured by the endoscope for extracting cues useful for surgeons, such as depth information. In particular, the 3D pose estimation of the surgical tools presents three important added values: (1) to extract objective parameters for the surgical training stage, (2) to develop an image-guided surgery based on the knowledge of the surgery tools localization, (3) to design new roboticsystems for an automatic laparoscope positioning, according to the visual feedback. Tool’s shape and orientation in the image is the key to get its 3D position. This work presents an image analysis for automatic laparoscopic tool’s detection along the recorded video without extra tool markers, using an edges detection strategy. Also, this analysis includes a previous stage of barrel distortion correction for videoendoscopic image

    Estudio de la abducción del hombro mediante videofotogrametría (VFG) y radiología seriada (RX) simultánea

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    El complejo articular del hombro posee la mayor movilidad de todas las articulaciones del cuerpo. Está formado por un conjunto de estructuras: articulación escapulohumeral, acromioclavicular, esternoclavicular, escapulotorácica (seudoarticulación de la escápula con la pared torácica) que actuan coordinadamente unas con otras para situar la extremidad superior y, en definitiva la mano, en cualquier sitio del espacio. El estudio del movimiento de este complejo articular del hombro ha sido motivo de muchas investigaciones que han generado temas de controversia durante los últimos cien años. Desde su origen, las articulaciones han ido evolucionando hasta especializarse para efectuar unos determinados movimientos más específicos y precisos, al mismo tiempo que han ido abandonando otros. La articulaciones multiaxiales, las más proximales de las extremidades como el muslo, son las que han persistido con un mayor grado de movilidad y las que, por tanto, requieren un control muscular más preciso. La evolución hacia la bipedestación, implica una serie de cambios: aparición de lordosis en la columna, aumento del diámetro transversal del tórax juntamente con un desplazamiento hacia atrás de la clavícula y la escápula permitiendo así mayor amplitud de movimientos, sobretodo en la rotación y en la función prensil de la extremidad superior. En el muslo, se sacrificó la estabilidad para adquirir más movilidad4

    Coulomb Dissociation of 27P^{27}P

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    Chemical Modification of a Dehydratase Enzyme Involved in Bacterial Virulence by an Ammonium Derivative: Evidence of its Active Site Covalent Adduct

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    The first example of an ammonium derivative that causes a specific modification of the active site of type I dehydroquinase (DHQ1), a dehydratase enzyme that is a promising target for antivirulence drug discovery, is described. The resolution at 1.35 Å of the crystal structure of DHQ1 from Salmonella typhi chemically modified by this ammonium derivative revealed that the ligand is covalently attached to the essential Lys170 through the formation of an amine. The detection by mass spectroscopy of the reaction intermediates, in conjunction with the results of molecular dynamics simulations, allowed us to explain the inhibition mechanism and the experimentally observed differences between S. typhi and Staphylococcus aureus enzymes. The results presented here reveal that the replacement of Phe225 in St-DHQ1 by Tyr214 in Sa-DHQ1 and its hydrogen bonding interaction with the conserved water molecule observed in several crystal structures protects the amino adduct against further dehydration/aromatization reactions. In contrast, for the St-DHQ1 enzyme, the carboxylate group of Asp114, with the assistance of this water molecule, would trigger the formation of a Schiff base that can undergo further dehydration reactions until full aromatization of the cyclohexane ring is achieved. Moreover, in vitro antivirulence studies showed that the reported compound is able to reduce the ability of Salmonella Enteritidis to kill A459 respiratory cells. These studies have identified a good scaffold for the design of irreversible inhibitors that can be used as drugs and has opened up new opportunities for the development of novel antivirulence agents by targeting the DHQ1 enzymeFinancial support from the Spanish Ministry of Science and Innovation (SAF2013-42899-R), Xunta de Galicia (GRC2013-041), and the European Regional Development Fund (ERDF) is gratefully acknowledged. E.L. thanks the Xunta de Galicia for his postdoctoral fellowship. A.B. thanks the Miguel Servet Programme ISCIII-FEDER (CP13/00226) and the ISCIIIGeneral Subdirection of Assesment and Promotion of the Research (PI14/00059) for financial supportS

    Coulomb dissociation of P 27 at 500 MeV/u

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    The proton-capture reaction Si26(p,γ)P27 was studied via Coulomb dissociation (CD) of P27 at an incident energy of about 500 MeV/u. The three lowest-lying resonances in P27 have been populated and their resonance strengths have been measured. In addition, a nonresonant direct-capture component was clearly identified and its astrophysical S factor measured. The experimental results are compared to Monte Carlo simulations of the CD process using a semiclassical model. Our thermonuclear reaction rates show good agreement with the rates from a recent compilation. With respect to the nuclear structure of P27 we have found evidence for a negative-parity intruder state at 2.88-MeV excitation energy. © 2016 American Physical Society

    Beyond the neutron drip line: The unbound oxygen isotopes (25)O and (26)O

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    This is the publisher's version, and is also available electronically from http://journals.aps.org/prc/abstract/10.1103/PhysRevC.88.034313.The very neutron-rich oxygen isotopes 25O and 26O are investigated experimentally and theoretically. The unbound states are populated in an experiment performed at the R3B-LAND setup at GSI via proton-knockout reactions from 26F and 27F at relativistic energies around 442 and 414 MeV/nucleon, respectively. From the kinematically complete measurement of the decay into 24O plus one or two neutrons, the 25O ground-state energy and width are determined, and upper limits for the 26O ground-state energy and lifetime are extracted. In addition, the results provide indications for an excited state in 26O at around 4 MeV. The experimental findings are compared to theoretical shell-model calculations based on chiral two- and three-nucleon (3N) forces, including for the first time residual 3N forces, which are shown to be amplified as valence neutrons are added
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