1,698 research outputs found

    Field dependent transition to the non-linear regime in magnetic hyperthermia experiments : comparison between maghemite, copper, zinc, nickel and cobalt ferrite nanoparticles of similar sizes

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    Further advances inmagnetic hyperthermiamight be limited by biological constraints, such as using sufÔ¨Āciently low frequencies and low Ô¨Āeld amplitudes to inhibit harmfuleddy currents inside the patient‚Äôs body. These incite the need to optimize the heatingefÔ¨Āciency of the nano particles, referred to as the speciÔ¨Āc absorption rate (SAR).Among the several properties currently under research, one of particular importance is the transition from the linear to the non-linear regime that takes place as the Ô¨Āeld amplitude is increased, an aspect where the magnetic anisotropy is expected to play a fundamental role. In this paper we investigate the heating properties of cobalt ferrite and maghemite nano particles under the inÔ¨āuence of a 500 kHz sinusoidal magneticÔ¨Āeld with varying amplitude, up to 134 Oe. The particles were characterized byTEM, XRD, FMR and VSM, from which most relevant morphological, structural and magnetic properties were inferred. Both materials have similar size distributions and saturation magnetization, but strikingly different magnetic anisotropies. Frommagnetic hyperthermia experiments we found that, while at low Ô¨Āelds maghemiteis the best nanomaterial for hyperthermia applications, above a critical Ô¨Āeld, close to the transition from the linear to the non-linear regime, cobalt ferrite becomesmore efÔ¨Ācient. The results were also analyzed with respect to the energy conversionefÔ¨Āciency and compared with dynamic hysteresis simulations. Additional analysiswith nickel, zinc and copper-ferrite nanoparticles of similar sizes conÔ¨Ārmed the importance of the magnetic anisotropy and the damping factor. Further, the analysis of the characterization parameters suggested core-shell nanostructures, probably due to a surface passivation process during the nanoparticle synthesis. Finally, we discussed the effect of particle-particle interactions and its consequences, in particular regarding discrepancies between estimated parameters and expected theoretical predictions

    Recomendaciones para gestantes con diabetes: conclusiones del Consenso reunido por convocatoria del Comité de Diabetes y Embarazo de la SAD

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    La diabetes gestacional es una alteraci√≥n de la tolerancia a la glucosa con severidad variable que comienza o es reconocida por primera vez durante el embarazo en curso. Esta definici√≥n es v√°lida independientemente del tratamiento que requiera, de si se trata de una diabetes previa al embarazo que no fue diagnosticada, o si la alteraci√≥n del metabolismo hidrocabonado persiste al concluir la gestaci√≥n. El presente trabajo, realizado¬†por Consenso en el Comit√© de Diabetes y Embarazo de la Sociedad Argentina de Diabetes,¬†actualiza los criterios diagn√≥sticos de la diabetes gestacional, as√≠ como tambi√©n el tratamiento, seguimiento y control de la patolog√≠a tanto durante la gestaci√≥n, como en el parto y el puerperio.Fil: Faingold, Mar√≠a Cristina.Fil: Lamela, C..Fil: Gheggi, Mar√≠a Soledad. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas; ArgentinaFil: Lapertosa, Silvia.Fil: Di Marco, Ingrid.Fil: Basualdo, Mar√≠a Natalia.Fil: Rovira, Marta Graciela. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Oficina de Coordinaci√≥n Administrativa Houssay. Centro de Estudios Farmacol√≥gicos y Bot√°nicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacol√≥gicos y Bot√°nicos; ArgentinaFil: Jawerbaum, Alicia Sandra. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Oficina de Coordinaci√≥n Administrativa Houssay. Centro de Estudios Farmacol√≥gicos y Bot√°nicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacol√≥gicos y Bot√°nicos; ArgentinaFil: Glatstein, Lucia. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Oficina de Coordinaci√≥n Administrativa Houssay. Centro de Estudios Farmacol√≥gicos y Bot√°nicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacol√≥gicos y Bot√°nicos; ArgentinaFil: L√≥pez, C..Fil: Caama√Īo, A..Fil: Salcedo, L..Fil: Rodr√≠guez, Mar√≠a Elena.Fil: Alvari√Īas J.

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

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    This paper presents measurements of the W+‚Üíőľ+őĹW^+ \rightarrow \mu^+\nu and W‚ąí‚Üíőľ‚ąíőĹW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

    Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in ‚ąös=13‚ÄČTeV pp collisions with the ATLAS detector