Thermal behaviour of natural ester based oil used in distribution transformers

This work compares the thermal behavior of a distribution transformer when using as dielectric liquid a mineral oil or natural esters. These cases have been analyzed using Finite Elements Method (FEM) at the software COMSOL Multiphysics® with a 3D-symmetrical model through the Heat Transfer in Solid module. The results of simulations show a higher values of maximum temperature in mineral oil submerged transformer than in natural ester, for the same operational conditions

The supersymmetric modified Poschl-Teller and delta-well potentials

New supersymmetric partners of the modified Poschl-Teller and the Dirac's delta well potentials are constructed in closed form. The resulting one-parametric potentials are shown to be interrelated by a limiting process. The range of values of the parameters for which these potentials are free of singularities is exactly determined. The construction of higher order supersymmetric partner potentials is also investigated.Comment: 20 pages, LaTeX file, 4 eps figure

Synergistic information supports modality integration and flexible learning in neural networks solving multiple tasks

Striking progress has been made in understanding cognition by analyzing how the brain is engaged in different modes of information processing. For instance, so-called synergistic information (information encoded by a set of neurons but not by any subset) plays a key role in areas of the human brain linked with complex cognition. However, two questions remain unanswered: (a) how and why a cognitive system can become highly synergistic; and (b) how informational states map onto artificial neural networks in various learning modes. Here we employ an information-decomposition framework to investigate neural networks performing cognitive tasks. Our results show that synergy increases as networks learn multiple diverse tasks, and that in tasks requiring integration of multiple sources, performance critically relies on synergistic neurons. Overall, our results suggest that synergy is used to combine information from multiple modalities—and more generally for flexible and efficient learning. These findings reveal new ways of investigating how and why learning systems employ specific information-processing strategies, and support the principle that the capacity for general-purpose learning critically relies on the system’s information dynamics

Extended WKB method, resonances and supersymmetric radial barriers

Semiclassical approximations are implemented in the calculation of position and width of low energy resonances for radial barriers. The numerical integrations are delimited by t/T<<8, with t the period of a classical particle in the barrier trap and T the resonance lifetime. These energies are used in the construction of `haired' short range potentials as the supersymmetric partners of a given radial barrier. The new potentials could be useful in the study of the transient phenomena which give rise to the Moshinsky's diffraction in time.Comment: 12 pages, 4 figures, 3 table

Optical potentials using resonance states in Supersymmetric Quantum Mechanics

Complex potentials are constructed as Darboux-deformations of short range, radial nonsingular potentials. They behave as optical devices which both refracts and absorbs light waves. The deformation preserves the initial spectrum of energies and it is implemented by means of a Gamow-Siegert function (resonance state). As straightforward example, the method is applied to the radial square well. Analytical derivations of the involved resonances show that they are `quantized' while the corresponding wave-functions are shown to behave as bounded states under the broken of parity symmetry of the related one-dimensional problem.Comment: 16 pages, 6 figures, 1 tabl

Calculation of Band Edge Eigenfunctions and Eigenvalues of Periodic Potentials through the Quantum Hamilton - Jacobi Formalism

We obtain the band edge eigenfunctions and the eigenvalues of solvable periodic potentials using the quantum Hamilton - Jacobi formalism. The potentials studied here are the Lam{\'e} and the associated Lam{\'e} which belong to the class of elliptic potentials. The formalism requires an assumption about the singularity structure of the quantum momentum function $p$, which satisfies the Riccati type quantum Hamilton - Jacobi equation, $p^{2} -i \hbar \frac{d}{dx}p = 2m(E- V(x))$ in the complex $x$ plane. Essential use is made of suitable conformal transformations, which leads to the eigenvalues and the eigenfunctions corresponding to the band edges in a simple and straightforward manner. Our study reveals interesting features about the singularity structure of $p$, responsible in yielding the band edge eigenfunctions and eigenvalues.Comment: 21 pages, 5 table

Coherent states for Hamiltonians generated by supersymmetry

Coherent states are derived for one-dimensional systems generated by supersymmetry from an initial Hamiltonian with a purely discrete spectrum for which the levels depend analytically on their subindex. It is shown that the algebra of the initial system is inherited by its SUSY partners in the subspace associated to the isospectral part or the spectrum. The technique is applied to the harmonic oscillator, infinite well and trigonometric Poeschl-Teller potentials.Comment: LaTeX file, 26 pages, 3 eps figure

Effect of confinement by SARS-CoV-2 on the degree of steatohepatitis in university students from Reynosa, Tamaulipas

Introduction: Healthy lifestyles are relevant for several diseases, steatohepatitis, although little known, is common in young people. There are reasons to be concerned about homebound college youth who are at risk for steatohepatitis. By restricting the mobility of the population, the risk factors for weight gain and the intake of calorie-dense foods increase, which are elements associated with steatohepatitis. Objective: To determine the effect of confinement during the COVID-19 pandemic on the degree of steatohepatitis by comparing transient elastography results taken before and after confinement. Method: Longitudinal study. A sample of 114 young university students of random sex was included. The transient elastography technique (FibroScan) was implemented, determining the degrees of steatosis and hepatic fibrosis by performing the test before and after the confinement of the participants. Student´s t-test was used to analyse the differences in the degrees of steatohepatitis before and after confinement. Results: the degrees of steatosis during the first sampling were S0 (52.6%), S1 (14.9%), S2 (5.3%) and S3 (27.2%) (m = 250.89, DE= ± 56.91), in the second sampling were presented S0 (56.1%), S1 (13.2%), S2 (5.3%) and S3 (5.4%) (m = 243.81, DE = ± 52.330), the relation of both samples was (p = 0.131). The results in the degrees of fibrosis in the first sampling were F0 (91.4%), F1 (6.1%). F2 (2.6%) (m= 4.80, DE = ±1.11), in the second F1 (95.6%), F2 (3.5) and F2 (0.9%) (m = 4.33, DE = ±1.16) and the relation of the two sampling was (p= 0.000). Conclusions: The degrees of hepatic fibrosis presented significant changes, on the other hand, steatosis tends to decrease, but the change is not significant, however, it is necessary to investigate with third variables to detect other factors involved in the changes

Quantifying synergy and redundancy in multiplex networks

Understanding how different networks relate to each other is key for obtaining a greater insight into complex systems. Here, we introduce an intuitive yet powerful framework to characterise the relationship between two networks, comprising the same nodes. We showcase our framework by decomposing the shortest paths between nodes as being contributed uniquely by one or the other source network, or redundantly by either, or synergistically by the two together. Our approach takes into account the networks' full topology, but it also provides insights at multiple levels of resolution: from global statistics, to individual paths of different length. We show that this approach is widely applicable, from brains to the London transport system. In humans and across $123$ other species, we demonstrate that reliance on unique contributions by long-range white matter fibers is a conserved feature of mammalian structural connectomes. Across species, we also find that efficient communication relies on significantly greater synergy between long-range and short-range fibers than expected by chance, and significantly less redundancy. Our framework may find applications to help decide how to trade-off different desiderata when designing network systems, or to evaluate their relative presence in existing systems, whether biological or artificial