Inverse cascades sustained by the transfer rate of angular momentum in a 3D turbulent flow

The existence of energy cascades as signatures of conserved magnitudes is one of the universal characteristics of turbulent flows. In homogeneous 3D turbulence, the energy conservation produces a direct cascade from large to small scales, although in 2D, it produces an inverse cascade pointing towards small wave numbers. In this Letter, we present the first evidence of an inverse cascade in a fully developed 3D experimental turbulent flow where the conserved magnitude is the angular momentum. Two counterrotating flows collide in a central region where very large fluctuations are produced, generating a turbulent drag that transfers the external torque between different fluid layers

Role of the oxygen plasma during in situ growth of YBa2Cu3O6+x thin films by pulsed laser deposition

The incorporation of oxygen into YBa2Cu3O6+x (YBaCuO) thin films during in situ growth by pulsed laser deposition (PLD) has been investigated as a function of the ablation conditions. A quenching technique has been used immediately after termination of growth to avoid any oxygen in or out-diffusion during the cooling down step. It is shown that superconducting YBaCuO thin films can be formed without any post-oxygenation procedure, contrary to what is expected from the (Image, T) thermodynamic diagram. Moreover, it is found that there is an optimal target-substrate distance, D, for each O2 deposition pressure, Image, that leads to the higher critical temperature (i.e., higher oxygenation) as well as to the best structural and morphological properties of quenched films. The results are discussed considering the formation of reactive oxygen in the laser-induced plasma during film growth

Luminescent Optical Fiber Oxygen Sensor following Layer-by-layer Method

AbstractA sensor based on luminescence has been prepared depositing the luminescent complex platinum tetrakis pentrafluorophenyporphine (PtTFPP) onto a plastic-clad silica (PCS) optical fiber. The sensing film is constructed in terms of Layer-by-Layer method. A LED centered at 400nm was used to interrogate the sensor in a reflection configuration, registering a luminescent signal from the sensing material located at 648nm. The transduction principle is based on the quenching suffered by PtTFPP as the oxygen (O2) concentration increases. The sensor was characterized for O2 concentrations from 0% to 75%, showing a linear Stern–Volmer relationship (R2 = 0.9962)

Gravitational waveforms from a point particle orbiting a Schwarzschild black hole

We numerically solve the inhomogeneous Zerilli-Moncrief and Regge-Wheeler equations in the time domain. We obtain the gravitational waveforms produced by a point-particle of mass $\mu$ traveling around a Schwarzschild black hole of mass M on arbitrary bound and unbound orbits. Fluxes of energy and angular momentum at infinity and the event horizon are also calculated. Results for circular orbits, selected cases of eccentric orbits, and parabolic orbits are presented. The numerical results from the time-domain code indicate that, for all three types of orbital motion, black hole absorption contributes less than 1% of the total flux, so long as the orbital radius r_p(t) satisfies r_p(t)> 5M at all times.Comment: revtex4, 24 pages, 23 figures, 3 tables, submitted to PR

The effect of calcitriol, paricalcitol, and a calcimimetic on extraosseous calcifications in uremic rats

Vitamin D derivatives and calcimimetics are used to treat secondary hyperparathyroidism in patients with chronic renal failure. We investigated the effect of calcitriol, paricalcitol, and the calcimimetic AMG 641 on soft-tissue calcification in uremic rats with secondary hyperparathyroidism. Control and uremic rats were treated with vehicle, calcitriol, paricalcitol, AMG 641, or a combination of AMG 641 plus calcitriol or paricalcitol. Parathyroid hormone levels were reduced by all treatments but were better controlled by the combination of paricalcitol and AMG 641. The calcimimetic alone did not induce extraosseous calcification but co-administration of AMG 641 reduced soft-tissue calcification and aortic mineralization in both calcitriol- and paricalcitol-treated rats. Survival was significantly reduced in rats treated with calcitriol and this mortality was attenuated by co-treatment with AMG 641. Our study shows that extraskeletal calcification was present in animals treated with calcitriol and paricalcitol but not with AMG 641. When used in combination with paricalcitol, AMG 641 provided excellent control of secondary hyperparathyroidism and prevented mortality associated with the use of vitamin D derivatives without causing tissue calcification

Invariant Measures and Decay of Correlations for a Class of Ergodic Probabilistic Cellular Automata

We give new sufficient ergodicity conditions for two-state probabilistic cellular automata (PCA) of any dimension and any radius. The proof of this result is based on an extended version of the duality concept. Under these assumptions, in the one dimensional case, we study some properties of the unique invariant measure and show that it is shift-mixing. Also, the decay of correlation is studied in detail. In this sense, the extended concept of duality gives exponential decay of correlation and allows to compute explicitily all the constants involved

An analysis of existing production frameworks for statistical and geographic information: Synergies, gaps and integration

The production of official statistical and geospatial data is often in the hands of highly specialized public agencies that have traditionally followed their own paths and established their own production frameworks. In this article, we present the main frameworks of these two areas and focus on the possibility and need to achieve a better integration between them through the interoperability of systems, processes, and data. The statistical area is well led and has well-defined frameworks. The geospatial area does not have clear leadership and the large number of standards establish a framework that is not always obvious. On the other hand, the lack of a general and common legal framework is also highlighted. Additionally, three examples are offered: the first is the application of the spatial data quality model to the case of statistical data, the second of the application of the statistical process model to the geospatial case, and the third is the use of linked geospatial and statistical data. These examples demonstrate the possibility of transferring experiences/advances from one area to another. In this way, we emphasize the conceptual proximity of these two areas, highlighting synergies, gaps, and potential integration. © 2021 by the authors. Licensee MDPI, Basel, Switzerland