University of Oviedo

About: University of Oviedo is a education organization based out in Oviedo, Spain. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 13423 authors who have published 31649 publications receiving 844799 citations. The organization is also known as: Universidá d'Uviéu & Universidad de Oviedo.

GOLLUM: a next-generation simulation tool for electron, thermal and spin transport

Abstract: We have developed an efficient simulation tool 'GOLLUM' for the computation of electrical, spin and thermal transport characteristics of complex nanostructures. The new multi-scale, multi-terminal tool addresses a number of new challenges and functionalities that have emerged in nanoscale-scale transport over the past few years. To illustrate the flexibility and functionality of GOLLUM, we present a range of demonstrator calculations encompassing charge, spin and thermal transport, corrections to density functional theory such as LDA+U and spectral adjustments, transport in the presence of non-collinear magnetism, the quantum-Hall effect, Kondo and Coulomb blockade effects, finite-voltage transport, multi-terminal transport, quantum pumps, superconducting nanostructures, environmental effects and pulling curves and conductance histograms for mechanically-controlled-break-junction experiments.

A Universal-Input Single-Stage High-Power-Factor Power Supply for HB-LEDs Based on Integrated Buck-Flyback Converter

Abstract: Due to the high rise in luminous efficiency that HB-LEDs have experienced in the last recent years, many new applications have been researched. In this paper, a streetlight LED application will be covered, using the Integrated Buck-Flyback Converter developed in previous works, which performs power factor correction (PFC) from a universal ac source, as well as a control loop using the LM3524 IC, which allows PWM dimming operation mode. Firstly, the LED load will be linearized and modeled in order to calculate the IBFC topology properly. Afterwards, the converter will be calculated, presenting the one built in the lab. Secondly, the converter will be modeled in order to build the closed loop system, modeling the current sensor as well in order to develop an adequate controller. Finally, experimental results obtained from the lab tests will be presented.

Search for Heavy Neutral Leptons in Events with Three Charged Leptons in Proton-Proton Collisions at √s = 13 TeV

Abstract: A search for a heavy neutral lepton N of Majorana nature decaying into a W boson and a charged lepton is performed using the CMS detector at the LHC. The targeted signature consists of three prompt charged leptons in any flavor combination of electrons and muons. The data were collected in proton-proton collisions at a center-of-mass energy of 13 TeV, with an integrated luminosity of 35.9 fb^(−1). The search is performed in the N mass range between 1 GeV and 1.2 TeV. The data are found to be consistent with the expected standard model background. Upper limits are set on the values of |V_(eN)|^2and |V_(μN)|^2, where V_(lN) is the matrix element describing the mixing of N with the standard model neutrino of flavor l. These are the first direct limits for N masses above 500 GeV and the first limits obtained at a hadron collider for N masses below 40 GeV.

Aging and chronic DNA damage response activate a regulatory pathway involving miR‐29 and p53

Abstract: Aging is a multifactorial process that affects most of the biological functions of the organism and increases susceptibility to disease and death. Recent studies with animal models of accelerated aging have unveiled some mechanisms that also operate in physiological aging. However, little is known about the role of microRNAs (miRNAs) in this process. To address this question, we have analysed miRNA levels in Zmpste24-deficient mice, a model of Hutchinson–Gilford progeria syndrome. We have found that expression of the miR-29 family of miRNAs is markedly upregulated in Zmpste24−/− progeroid mice as well as during normal aging in mouse. Functional analysis revealed that this transcriptional activation of miR-29 is triggered in response to DNA damage and occurs in a p53-dependent manner since p53−/− murine fibroblasts do not increase miR-29 expression upon doxorubicin treatment. We have also found that miR-29 represses Ppm1d phosphatase, which in turn enhances p53 activity. Based on these results, we propose the existence of a novel regulatory circuitry involving miR-29, Ppm1d and p53, which is activated in aging and in response to DNA damage.

Planck early results - XXIV. Dust in the diffuse interstellar medium and the galactic halo

Abstract: This paper presents the first results from a comparison of Planck dust maps at 353, 545 and 857GHz, along with IRAS data at 3000 (100 μm) and 5000GHz (60 μm), with Green Bank Telescope 21-cm observations of Hi in 14 fields covering more than 800deg(2) at high Galactic latitude. The main goal of this study is to estimate the far-infrared to sub-millimeter (submm) emissivity of dust in the diffuse local interstellar medium (ISM) and in the intermediate-velocity (IVC) and high-velocity clouds (HVC) of the Galactic halo. Galactic dust emission for fields with average Hi column density lower than 2 × 10(20) cm(-20) is well correlated with 21-cm emission because in such diffuse areas the hydrogen is predominantly in the neutral atomic phase. The residual emission in these fields, once the Hi-correlated emission is removed, is consistent with the expected statistical properties of the cosmic infrared background fluctuations. The brighter fields in our sample, with an average Hi column density greater than 2 × 10(20) cm(-2), show significant excess dust emission compared to the Hi column density. Regions of excess lie in organized structures that suggest the presence of hydrogen in molecular form, though they are not always correlated with CO emission. In the higher Hi column density fields the excess emission at 857 GHz is about 40% of that coming from the Hi, but over all the high latitude fields surveyed the molecular mass faction is about 10%. Dust emission from IVCs is detected with high significance by this correlation analysis. Its spectral properties are consistent with, compared to the local ISM values, significantly hotter dust (T ~ 20 K), lower submm dust opacity normalized per H-atom, and a relative abundance of very small grains to large grains about four times higher. These results are compatible with expectations for clouds that are part of the Galactic fountain in which there is dust shattering and fragmentation. Correlated dust emission in HVCs is not detected; the average of the 99.9% confidence upper limits to the emissivity is 0.15 times the local ISM value at 857 and 3000GHz, in accordance with gas phase evidence for lower metallicity and depletion in these clouds. Unexpected anti-correlated variations of the dust temperature and emission cross-section per H atom are identified in the local ISM and IVCs, a trend that continues into molecular environments. This suggests that dust growth through aggregation, seen in molecular clouds, is active much earlier in the cloud condensation and star formation processes.