543 research outputs found

    Direct determination of the collective pinning radius in high temperature superconductors

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    We study finite-size effects at the onset of the irreversible magnetic behaviour of micron-sized Bi2_2Sr2_2CaCu2_2O8+δ_{8+\delta} single crystals by using silicon micro-oscillators. We find an irreversibility line appearing well below the thermodynamic Bragg-glass melting line at a magnetic field which increases both with increasing the sample radius and with decreasing the temperature. We show that this size-dependent irreversibility line can be identified with the crossover between the Larkin and the random manifold regimes of the vortex lattice transverse roughness. Our method allows to determine the three-dimensional weak collective pinning Larkin radius in a {\it direct way}.Comment: 4 pages, 3 fig

    Estudio de arcillas excavadas con caolinita y dickita como materiales puzolánicos

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    En el presente estudio, diferentes muestras de arcillas excavadas fueron activadas térmicamente a 550 °C y 650 °C, estas arcillas con bajo contenido de caolinita y presencia de dickita tienen una explotación industrial limitada, pero se encuentran ampliamente disponibles en países en desarrollo y tienen el potencial para su uso como material puzolánico. Los efectos sobre la fijación de hidróxido de calcio y la resistencia a la compresión fueron evaluados en pastas de cal y morteros mezclados con arcillas excavadas calcinadas. Los resultados experimentales y la modelación estadística usando un análisis de regresión múltiple mostraron que la resistencia a la compresión a los 28 días se incrementa un 5% cuando los contenidos de caolinita y dickita se incrementan hasta un 20% y un 40% respectivamente, en una arcilla con ASE de 4000 cm2 /g calcinada a 550 °C. Igualmente, cuando se incrementa el ASE hasta 6000 cm2/g y la temperatura de calcinación hasta 650 °C, la resistencia a la compresión se incrementa 10% and 15%, respectivamente.In the present study, samples of excavated waste clays were thermally activated at 550 °C and 650 °C, these clays with low kaolinite content and presence of dickite have a limited industrial exploitation but are widely availability in developing countries and have the potential to use as pozzolanic material. The effects on the calcium hydroxide fixation and the compressive strength were evaluated in lime pastes and mortars blended with calcined excavated clays. The experimental results and statistical modelling using multiple regression analysis showed that the compressive strength at 28 days increased 5%, when the kaolinite increased up to 20% and dickite up to 40%, for a clay with SSA of 4000 cm2 /g and calcined at 550 °C. Also, by increasing SSA up to 6000 cm2 /g and calcination temperature up to 650 °C, the compressive strength increased 10% and 15%, respectively.Fil: Yanguatin, Hernan. Universidad Nacional de Colombia; ColombiaFil: Tironi, Alejandra. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; ArgentinaFil: Tobón, Jorge I.. Universidad Nacional de Colombia; Colombi

    Infrared Constraints on AGN Tori Models

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    This work focuses on the properties of dusty tori in active galactic nuclei (AGN) derived from the comparison of SDSS type 1 quasars with mid-Infrared (MIR) counterparts and a new, detailed torus model. The infrared data were taken by the Spitzer Wide-area InfraRed Extragalactic (SWIRE) Survey. Basic model parameters are constraint, such as the density law of the graphite and silicate grains, the torus size and its opening angle. A whole variety of optical depths is supported. The favoured models are those with decreasing density with distance from the centre, while there is no clear tendency as to the covering factor, ie small, medium and large covering factors are almost equally distributed. Based on the models that better describe the observed SEDs, properties such as the accretion luminosity, the mass of dust, the inner to outer radius ratio and the hydrogen column density are computed.Comment: 4 pages, 4 figures, to appear in "Infrared Diagnostics of Galaxy Evolution", ASP Conference Series, Pasadena, 14-16 November 200

    Natural ester fluids applications in transformers as a sustainable dielectric and coolant

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    New requirements for a better sustainable energy policy around the world is easy to observe, many projects in sustainable energy are developed wherein the academia works together the authorities and commercial firms such as electrical grid utilities. In distribution transformers one of the suggested solutions is to replace mineral oils used as dielectric and coolant for natural ester fluids, they provide improved technical properties making them a safe substitute of mineral oil. Natural esters are based on clean technology in order to guarantee requirements from utilities. The main goal of the present paper is to present a technical-economic analysis obtained from five years of applications of oil-immersed transformers using natural ester fluids in Colombia. The methodology considers forty-four oil-immersed distribution Transformers, a half use mineral oil and the other side use natural ester, operating under the same load regime. Results evidenced the feasibility of implementing this technology because the costs are very similar and the reduction of risks and environmental impact is considerable. © 2019 Author(s)

    The Autodepalmitoylating activity of APT maintains the spatial organization of Palmitoylated membrane proteins

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    The localization and signaling of S-palmitoylated peripheral membrane proteins is sustained by an acylation cycle in which acyl protein thioesterases (APTs) depalmitoylate mislocalized palmitoylated proteins on endomembranes. However, the APTs are themselves reversibly S-palmitoylated, which localizes thioesterase activity to the site of the antagonistc palmitoylation activity on the Golgi. Here, we resolve this conundrum by showing that palmitoylation of APTs is labile due to autodepalmitoylation, creating two interconverting thioesterase pools: palmitoylated APT on the Golgi and depalmitoylated APT in the cytoplasm, with distinct functionality. By imaging APT-substrate catalytic intermediates, we show that it is the depalmitoylated soluble APT pool that depalmitoylates substrates on all membranes in the cell, thereby establishing its function as release factor of mislocalized palmitoylated proteins in the acylation cycle. The autodepalmitoylating activity on the Golgi constitutes a homeostatic regulation mechanism of APT levels at the Golgi that ensures robust partitioning of APT substrates between the plasma membrane and the Golgi.Fil: Vartak, Nachiket. Institut Max Planck Fur Molekulare Physiologie; AlemaniaFil: Papke, Bjoern. Institut Max Planck Fur Molekulare Physiologie; AlemaniaFil: Grecco, Hernan Edgardo. Institut Max Planck Fur Molekulare Physiologie; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rossmannek, Lisaweta. Institut Max Planck Fur Molekulare Physiologie; AlemaniaFil: Waldmann, Herbert. Institut Max Planck Fur Molekulare Physiologie; AlemaniaFil: Hedberg, Christian. Institut Max Planck Fur Molekulare Physiologie; AlemaniaFil: Bastiaens, Philippe I. H.. Institut Max Planck Fur Molekulare Physiologie; Alemani

    Potential Energy savings in compressed air systems in industrialized cities. A case study in Barranquilla and Cartagena

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    The increase of energy consumption, global warming, resource depletion and the rise of policies focused on climate change and greenhouse gas emissions reductions, have promoted to countries and industries the implementation of strategies focused on increase energy efficiency and reduce GHG emissions. Compressed Air Systems (CASs) are one of the most widespread systems used in industry. In countries such as China, USA, Australia, France and Italy, CASs accounts around 10% of the overall electricity costs. In Colombia the energy used in the industrial sector, rise the 33 % of the total energy consumption, equal to 481.429 TJ/year; the electricity consumption is a 13 % of this value, equivalent to 13,3 TWh/year. This paper determine the potentials energy saving of CASs for two industrial cities of the Colombian Caribbean Coast region, showing that there is a high energy saving potential, around 50 GWh/year and a reduction of CO2 emissions of 10,702 tons of CO2/year, which can be taken in consideration by the government and organizations to develop projects focused on reduce energy consumption and mitigate CO2 emissions

    Potential energy savings and co2 emissions reduction in colombia compressed air systems

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    Compressed air (CA) is one of the most common systems used in industry. In countries such as Australia, Italia, France, China and USA, energy consumption of CA systems (CASs) contributes about to 10% of the total electricity consumption in industry. In Colombia, this value reaches 8%, highlighting the textile industry, with a 24% of consumption. Despite of all its advantages, CA is expensive, between 10 and 30% of consumed energy reaches the end-use point. Improvements to CASs can achieve between 20 and 60% of energy savings, with pay-back periods lower than two years. These are the reasons that they can be considered as one of the main targetsystems while planning energy efficiency actions in industry. Colombia through different strategies has proposed to implement a group of measures to improve energy efficiency and reduce electricity consumption to 2021 around 7%. Implementation of good practices in CASs is one of them. This paper is showed the share cost, electricity consumption and the savings potential of the CASs in the different divisions of the Colombian manufacturing sector, the main sectors to be involved as well as the potential savings and reduction of dioxide carbon emissions

    Feasibility study of combined dynamic imaging and lymphaticovenous anastomosis surgery for breast cancer-related lymphoedema.

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    Background Breast cancer-related lymphoedema (BCRL) presents a significant healthcare burden and adversely affects quality of life of breast cancer survivors. A prospective feasibility study was performed on lymphaticovenous anastomosis (LVA) for the treatment of BCRL.Methods Patients with BCRL underwent near-infrared spectroscopy with indocyanine green lymphatic mapping to identify suitable lymphatic channels for LVA. End-to-end anastomoses to subdermal venules were performed and patients recommenced compression garment therapy (CGT) after surgery. Volumetric assessment of the affected limb was performed at regular intervals using infrared perometry to calculate the excess volume reduction.Results Over a 24-month interval, 27 patients with BCRL underwent LVA. The mean duration of lymphoedema was 3·5 (range 0·5-18) years, and the mean number of LVAs performed was 3 (range 2-5). Twenty-four of the 27 patients completed 12-month follow-up. Patients exhibited three patterns of volumetric response following LVA: sustained response (16 patients), transient response (5) or no response (6). Sustained responders showed an excess volume reduction of -33·2 per cent at 12 months, and this correlated positively with the number of LVAs performed (r = -0·56, P = 0·034). Overall, ten patients were able to downgrade CGT after surgery, and two patients were CGT-free at 12 months.Conclusion LVA resulted in a sustained volume reduction in selected patients and may offset the burden of CGT. Further work is required to identify biomarkers that predict a favourable response to LVA surgery

    Z boson production in p+Pb collisions at sNN√=5.02 TeV measured with the ATLAS detector

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    The ATLAS Collaboration has measured the inclusive production of Z bosons via their decays into electron and muon pairs in p+Pb collisions at √ sNN = 5.02 TeV at the Large Hadron Collider. The measurements are made using data corresponding to integrated luminosities of 29.4 nb−1 and 28.1 nb−1 for Z → ee and Z → µµ, respectively. The results from the two channels are consistent and combined to obtain a cross section times the Z → `` branching ratio, integrated over the rapidity region |y ∗ Z | < 3.5, of 139.8 ± 4.8 (stat.) ± 6.2 (syst.) ± 3.8 (lumi.) nb. Differential cross sections are presented as functions of the Z boson rapidity and transverse momentum, and compared with models based on parton distributions both with and without nuclear corrections. The centrality dependence of Z boson production in p+Pb collisions is measured and analyzed within the framework of a standard Glauber model and the model’s extension for fluctuations of the underlying nucleon-nucleon scattering cross sectionFil: Aad, G.. Aix-Marseille Université; FranciaFil: Abbott, B.. Oklahoma State University; Estados UnidosFil: Abdallah, J.. Academia Sinica; ChinaFil: Abdinov, O.. Azerbaijan Academy of Sciences; AzerbaiyánFil: Aben, R.. University of Amsterdam; Países BajosFil: Alconada Verzini, María Josefina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Alonso, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Arduh, Francisco Anuar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Dova, Maria Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Monticelli, Fernando Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Wahlberg, Hernan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Otero y Garzon, Gustavo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Piegaia, Ricardo Nestor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Reisin, Hernan Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Sacerdoti, Sabrina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Zieminska, D.. Indiana University; Estados UnidosFil: Zimine, N. I.. Joint Institute for Nuclear Research ; RusiaFil: Zimmermann, C.. Universität Mainz; AlemaniaFil: Zimmermann, S.. Albert-Ludwigs-Universität; AlemaniaFil: Zinonos, Z.. Georg-August-Universität; AlemaniaFil: Zinser, M.. Universität Mainz; AlemaniaFil: Ziolkowski, M.. Universität Siegen ; AlemaniaFil: Živković, L.. University of Belgrade; SerbiaFil: Zobernig, G.. University of Wisconsin; Estados UnidosFil: Zoccoli, A.. Università di Bologna; ItaliaFil: Nedden, M. zur. Humboldt University; AlemaniaFil: Zurzolo, G.. Università di Napoli; ItaliaFil: Zwalinski, L.. Cern - European Organization For Nuclear Research; SuizaFil: The ATLAS Collaboration. No especifica
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