Ferroelectricity and structure of BaTiO3 grown on YBa2Cu3O7-d thin films

We have investigated the crystal structure and the ferroelectric properties of BaTiO3 thin films with YBa2Cu3O7-d as the bottom and Au as the top electrode. Epitaxial heterostructures of YBa2Cu3O7-d and BaTiO3 were prepared by dc and rf sputtering, respectively. The crystal structure of the films was characterised by x-ray diffraction. The ferroelectric behaviour of the BaTiO3 films was confirmed by hysteresis loop measurements using a Sawyer Tower circuit. We obtain a coercive field of 30 kV/cm and a remanent polarisation of 1.25 \muC/cm. At sub-switching fields the capacitance of the films obeys a relation analogous to the Rayleigh law. This behaviour indicates an interaction of domain walls with randomly distributed pinning centres. At a field of 5 MV/m we calculate 3% contribution of irreversible domain wall motion to the total dielectric constant.Comment: 12 pages and 9 figure

Detection of vortex tubes in solar granulation from observations with Sunrise

We have investigated a time series of continuum intensity maps and corresponding Dopplergrams of granulation in a very quiet solar region at the disk center, recorded with the Imaging Magnetograph eXperiment (IMaX) on board the balloon-borne solar observatory Sunrise. We find that granules frequently show substructure in the form of lanes composed of a leading bright rim and a trailing dark edge, which move together from the boundary of a granule into the granule itself. We find strikingly similar events in synthesized intensity maps from an ab initio numerical simulation of solar surface convection. From cross sections through the computational domain of the simulation, we conclude that these `granular lanes' are the visible signature of (horizontally oriented) vortex tubes. The characteristic optical appearance of vortex tubes at the solar surface is explained. We propose that the observed vortex tubes may represent only the large-scale end of a hierarchy of vortex tubes existing near the solar surface.Comment: Astrophysical Journal Letters: Sunrise Special Issue, reveived 2010 June 16; accepted 2010 August

Q value and half-life of double-electron capture in Os-184

Os-184 has been excluded as a promising candidate for the search of neutrinoless double-electron capture. High-precision mass measurements with the Penning-trap mass spectrometer TRIGA-TRAP resulted in a marginal resonant enhancement with = -8.89(58) keV excess energy to the 1322.152(22) keV 0+ excited state in W-184. State-of-the-art energy density functional calculations are applied for the evaluation of the nuclear matrix elements to the excited states predicting a strong suppression due to the large deformation of mother and daughter states. The half-life of the transition in Os-184 exceeds T_{1/2} > 1.3 10^{29} years for an effective neutrino mass of 1 eV.Comment: accepted in Phys. Rev.

Halo properties and secular evolution in barred galaxies

The halo plays a crucial role in the evolution of barred galaxies. Its near-resonant material absorbs angular momentum emitted from some of the disc particles and helps the bar become stronger. As a result, a bar (oval) forms in the inner parts of the halo of strongly barred disc galaxies. It is thinner in the inner parts (but still considerably fatter than the disc bar) and tends to spherical at larger radii. Its length increases with time, while always staying shorter than the disc bar. It is roughly aligned with the disc bar, which it trails only slightly, and it turns with roughly the same pattern speed. The bi-symmetric component of the halo density continues well outside the halo bar, where it clearly trails behind the disc bar. The length and strength of the disc and halo bars correlate; the former being always much stronger than the latter. If the halo is composed of weakly interacting massive particles, then the formation of the halo bar, by redistributing the matter in the halo and changing its shape, could influence the expected annihilation signal. This is indeed found to be the case if the halo has a core, but not if it has a steep cusp. The formation and evolution of the bar strongly affect the halo orbits. A fraction of them becomes near-resonant, similar to the disc near-resonant orbits at the same resonance, while another fraction becomes chaotic. Finally, a massive and responsive halo makes it harder for a central mass concentration to destroy the disc bar.Comment: 6 pages, 3 figures, to appear in "Island Universes - Structure and Evolution of Disk Galaxies" ed. R. S. de Jon

Regeneration performance of metal–organic frameworks

Notions about the reception of print fiction as well as new media texts have a strong tendency to fall back upon the dichotomy between naïve and critical reading. It is presupposed that reception will be characterized by either the one or the other. We will try to critique this dichotomy on the basis of the hypothesis that media cultural change brings with it new and hybrid textual forms, ways of reading, and patterns of reception which not lend themselves to description in simple terms of naïve or critical. We make a case for the necessity of transgressing the dominant assumptions of transactional reception theory within literary studies and instead move in the direction of what we call creative reading and media-reflexivity

Beneficial role of noise in Hf-based memristors

© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The beneficial role of noise in the performance of Hf-based memristors has been experimentally studied. The addition of an external gaussian noise to the bias circuitry positively impacts the memristors characteristics by increasing the OFF/ON resistances ratio. The known stochastic resonance effect has been observed, when changing the standard deviation of the noise. The influence of the additive noise on the memristor current-voltage characteristic and on the set and reset related parameters are also presented.This research was funded by Spanish MCIN/AEI/10.13039/501100011033, Project PID2019- 103869RB and TEC2017-90969-EXP.Peer ReviewedPostprint (author's final draft

Physics of the Muon Spectrometer of the ALICE Experiment

The main goal of the Muon spectrometer of the ALICE experiment at LHC is the measurement of heavy quark production in p+p, p+A and A+A collisions at LHC energies, via the muonic channel. Physics motivations and expected performances have been presented in this talk.Comment: 10 pages and 4 figures. Talk presented in the ICPAQGP Conference, February 8-12, 2005, Salt Lake City, Kolkata, India. Web page of the conference : http://www.veccal.ernet.in/~icpaqgp

Successful network inference from time-series data using Mutual Information Rate

This work uses an information-based methodology to infer the connectivity of complex systems from observed time-series data. We first derive analytically an expression for the Mutual Information Rate (MIR), namely, the amount of information exchanged per unit of time, that can be used to estimate the MIR between two finite-length low-resolution noisy time-series, and then apply it after a proper normalization for the identification of the connectivity structure of small networks of interacting dynamical systems. In particular, we show that our methodology successfully infers the connectivity for heterogeneous networks, different time-series lengths or coupling strengths, and even in the presence of additive noise. Finally, we show that our methodology based on MIR successfully infers the connectivity of networks composed of nodes with different time-scale dynamics, where inference based on Mutual Information fails

Comportamiento clínico epidemiológico del carcinoma escamocelular bucal de pacientes tratados en el hospital Universitario San Vicente de Paúl (HUSVP), Medellín, entre enero de 1990 y diciembre de 1996

ABSTRACT: Oral squamous cell carcinoma is a pathology that has a very low frequency in the Stomatology Service. The purpose of this article is to describe the clinical and epidemiological characteristics of the cases diagnosed in the HUSVP for the years of 1990 to 1996. Clinical records and files from the department of Pathology of the Hospital and of the School of Dentistry were analyzed. 228 cases were found, of them, the largest percentage corresponded to men of 60 years of age or older. The most affected site was the tongue (30%), followed by the floor of the mouth (20.7%) and the palate (17.7%).Smoking was reported by 67% of the patients, and alcohol consumption by 29.8%. A pre malignant lesion previous to the appearance of the cancer was detected in 56 cases, of these, leukoplakia was the most common. The most common stages of cancer detected were stage IV and III with 55.1% and 19.8% respectively; radio therapy in 46.1% of the cases and surgeries in the 39.6% of the cases were the most performed treatments. It is concluded that in the population studied, the oral squamous cell carcinoma is diagnosed mainly in older people and in advanced stages, this decreases the possibility of curative treatments and at the same time affects negatively the quality of life of patients; it is necessary to understand the clinical behavior, , the manifestations, the characteristics of the initial stages and the possible associated risk factors in order to make an early diagnosis and control of this neoplastic disease.RESUMEN: El carcinoma escamocelular bucal es una patología que se presenta con baja frecuencia en la consulta estomatológica. El propósito del estudio fue hacer la descripción de las características clínicas y epidemiológicas de los casos diagnosticados en el Hospital Universitario San Vicente de Paúl entre los años 1990 y 1996. Se analizaron las historias clínicas y los formatos de archivo del Departamento de Patología del Hospital y de la Facultad de Odontología de la Universidad de Antioquia. Se encontraron 228 casos, de los cuales el mayor porcentaje correspondía a hombres de sesenta años y más; la lengua fue el sitio más frecuentemente afectado (30%), seguida del suelo de boca (20,7%) y del paladar (17,7%). El tabaquismo fue un antecedente presente en el 67% de los casos y el consumo de alcohol en el 29,8%. Se detectó una lesión premaligna previa al desarrollo del cáncer en 56 casos, donde las leucoplasias fue la más común. Los estadios de cáncer que más se presentaron fueron el IV y el III con 55,1 y 19,8% respectivamente; la radioterapia en el 46,1% de los casos y la cirugía en el 39,6% fueron los tratamientos que más se realizaron. Se concluye que en la población estudiada el carcinoma escamocelular bucal se diagnostica principalmente en mayores de edad y en estadios avanzados, esto disminuye las probabilidades de éxito de los tratamientos curativos y a su vez desmejora la calidad de vida de los pacientes; es necesario conocer el comportamiento clínico, las manifestaciones, las características de los estadios iniciales y los posibles factores de riesgo asociados, con el fin de realizar el diagnóstico temprano y el control precoz de esta neoplasia

Mass hierarchy, 2-3 mixing and CP-phase with Huge Atmospheric Neutrino Detectors

We explore the physics potential of multi-megaton scale ice or water Cherenkov detectors with low ($\sim 1$ GeV) threshold. Using some proposed characteristics of the PINGU detector setup we compute the distributions of events versus neutrino energy $E_\nu$ and zenith angle $\theta_z$, and study their dependence on yet unknown neutrino parameters. The $(E_\nu - \theta_z)$ regions are identified where the distributions have the highest sensitivity to the neutrino mass hierarchy, to the deviation of the 2-3 mixing from the maximal one and to the CP-phase. We evaluate significance of the measurements of the neutrino parameters and explore dependence of this significance on the accuracy of reconstruction of the neutrino energy and direction. The effect of degeneracy of the parameters on the sensitivities is also discussed. We estimate the characteristics of future detectors (energy and angle resolution, volume, etc.) required for establishing the neutrino mass hierarchy with high confidence level. We find that the hierarchy can be identified at $3\sigma$ -- $10\sigma$ level (depending on the reconstruction accuracies) after 5 years of PINGU operation.Comment: 39 pages, 21 figures. Description of Fig.3 correcte