Valence instability of cerium under pressure in the Kondo-like perovskite La0.1_{0.1}Ce0.4_{0.4}Sr0.5_{0.5}MnO3_3

Effect of hydrostatic pressure and magnetic field on electrical resistance of the Kondo-like perovskite manganese oxide, La$_{0.1}$Ce$_{0.4}$Sr$_{0.5}$MnO$_3$ with a ferrimagnetic ground state, have been investigated up to 2.1 GPa and 9 T. In this compound, the Mn-moments undergo double exchange mediated ferromagnetic ordering at $T_{\rm C}$ $\sim$ 280 K and there is a resistance maximum, $T_{\rm max}$ at about 130 K which is correlated with an antiferromagnetic ordering of {\it cerium} with respect to the Mn-sublattice moments. Under pressure, the $T_{\rm max}$ shifts to lower temperature at a rate of d$T_{max}$/d$P$ = -162 K/GPa and disappears at a critical pressure $P_{\rm c}$ $\sim$ 0.9 GPa. Further, the coefficient, $m$ of $-logT$ term due to Kondo scattering decreases linearly with increase of pressure showing an inflection point in the vicinity of $P_{\rm c}$. These results suggest that {\it cerium} undergoes a transition from Ce$^{3+}$ state to Ce$^{4+}$/Ce$^{3+}$ mixed valence state under pressure. In contrast to pressure effect, the applied magnetic field shifts $T_{\rm max}$ to higher temperature presumably due to enhanced ferromagnetic Mn moments.Comment: to be published in Phys. Rev. B (rapid commun

Remarks on Bootstrap Percolation in Metric Networks

We examine bootstrap percolation in d-dimensional, directed metric graphs in the context of recent measurements of firing dynamics in 2D neuronal cultures. There are two regimes, depending on the graph size N. Large metric graphs are ignited by the occurrence of critical nuclei, which initially occupy an infinitesimal fraction, f_* -> 0, of the graph and then explode throughout a finite fraction. Smaller metric graphs are effectively random in the sense that their ignition requires the initial ignition of a finite, unlocalized fraction of the graph, f_* >0. The crossover between the two regimes is at a size N_* which scales exponentially with the connectivity range \lambda like_* \sim \exp\lambda^d. The neuronal cultures are finite metric graphs of size N \simeq 10^5-10^6, which, for the parameters of the experiment, is effectively random since N<< N_*. This explains the seeming contradiction in the observed finite f_* in these cultures. Finally, we discuss the dynamics of the firing front

Inelastic Analysis of Mdof Systems Damaged by Earthquakes, Posteriorly Subjected to Wind Load

This paper deals with the analysis of the inelastic response of buildings originally damaged by earthquakes and subjected to earthquake aftershock and wind loading. The overall aim is to establish the effect of wind actions on structural stability. To that end, one four-story bare frame benchmarked by the European Laboratory for Structural Assessment, is subject to various levels of winds and earthquake joint load while monitoring changes on the ductility demand. In this paper is shown that the combined action of strong winds and earthquakes, however its low probability of occurrence, would cause a decrease of strength reduction factors and considerably increase the ductility demand of damaged infrastructure hence inducing additional risks that would otherwise remain unquantified. The paper examines the non-linear performance of Multi-degree of freedom systems subject to various levels of winds and earthquake load and deals with the estimation of strength reduction factors. This is a relatively unexplored area of research which builds on past developments whereby inelastic performance of buildings has been discussed. It also links to various other paths of development such as structural reliability, forensic and control systems engineering. Doi: 10.28991/cej-2021-03091675 Full Text: PD

Bose-Einstein Condensation of 88^{88}Sr Through Sympathetic Cooling with 87^{87}Sr

We report Bose-Einstein condensation of $^{88}$Sr, which has a small, negative s-wave scattering length ($a_{88}=-2$\,$a_0$). We overcome the poor evaporative cooling characteristics of this isotope by sympathetic cooling with $^{87}$Sr atoms. $^{87}$Sr is effective in this role in spite of the fact that it is a fermion because of the large ground state degeneracy arising from a nuclear spin of $I=9/2$, which reduces the impact of Pauli blocking of collisions. We observe a limited number of atoms in the condensate ($N_{max}\approx 10^4$) that is consistent with the value of $a_{88}$ and the optical dipole trap parameters.Comment: 4 pages, 4 figure

A Novel Low-Cost Sensor Prototype for Nocturia Monitoring in Older People

Indexación: Scopus.This work was supported in part by CORFO - CENS 16CTTS-66390 through the National Center on Health Information Systems, in part by the National Commission for Scientific and Technological Research (CONICYT) through the program STIC-AMSUD 17STIC-03: ‘‘e-MONITOR âĂŞ Chronic Disease: Ambient Assisted Living and vital teleMONOTORing for e-health,’’ FONDEF ID16I10449 ‘‘Sistema inteligente para la gestión y análisis de la dotación de camas en la red asistencial del sector público,’’ and MEC80170097 ‘‘Red de colaboración científica entre universidades nacionales e internacionales para la estructuración del doctorado y magister en informática médica en la Universidad de Valparaíso.’’ The work of V. H. C. de Albuquerque was supported by the Brazilian National Council for Research and Development (CNPq) under Grant #304315/2017-6.Nocturia is frequently defined as the necessity to get out of bed at least one time during the night to urinate, with each of these episodes being preceded and continued by sleep. Several studies suggest that an increase of nocturia is seen with the onset of age, occurring in around 70% of adults over the age of 70. Its appearance is associated with detrimental quality of life for those who present nocturia, since it leads to daytime sleepiness, cognitive dysfunction, among others. Currently, a voiding diary is necessary for nocturia assessment; these are prone to bias due to their inherent subjectivity. In this paper, we present the design of a low-cost device that automatically detects micturition events. The device obtained 73% in sensibility and 81% in specificity; these results show that systems such as the proposed one can be a valuable tool for the medical team when evaluating nocturia. © 2013 IEEE.https://ieeexplore.ieee.org/document/845445

A Comparison of Alcohol Use and Correlates of Drinking Patterns among Men and Women Aged 50 and Above in Ghana and South Africa

Alcohol use is an important part of the health profile of older adults, and little is known about the prevalence and correlates of drinking among this population in Ghana and South Africa. This study aimed to describe and compare the prevalence and correlates of drinking patterns among adults aged 50 and above in Ghana and South Africa, and to determine which correlates explain differences in drinking patterns between the two countries. We used data from the WHO Study on global AGEing and adult health (SAGE) conducted in Ghana and South Africa. The sample of participants aged 50+ was 4289 in Ghana and 3666 in South Africa. Alcohol measures included a self-report of the number of standard drinks consumed over the previous 7 days, from which we constructed the mutually exclusive drinking categories of lifetime abstainers, low risk and at risk drinkers by gender. We used multivariate analysis to identify independent correlates for the different drinking patterns and those contributing to drinking differences between countries. Lifetime abstainers comprised 41.9% and 74.6% of the Ghana and South Africa samples, respectively. Among current drinkers, there were significantly more at risk drinkers among both genders in South Africa compared to Ghana. Factors independently associated drinking patterns differed between countries and by gender, although similarities included religion and smoking. Smoking status contributed to the difference in drinking patterns between Ghana and South Africa more than socio-demographics. Different patterns of drinking and associated correlates exist among older adults between Ghana and South Africa, and differences in drinking patterns were more strongly associated with smoking than socio-demographics. Drinking may increase in Ghana as economic development continues, although other health behaviors such as smoking may also play an important role and should be monitored in future surveys