Geometric thermodynamics: black holes and the meaning of the scalar curvature

In this paper we show that the vanishing of the scalar curvature of Ruppeiner-like metrics does not characterize the ideal gas. Furthermore, we claim through an example that flatness is not a sufficient condition to establish the absence of interactions in the underlying microscopic model of a thermodynamic system, which poses a limitation on the usefulness of Ruppeiner's metric and conjecture. Finally, we address the problem of the choice of coordinates in black hole thermodynamics. We propose an alternative energy representation for Kerr-Newman black holes that mimics fully Weinhold's approach. The corresponding Ruppeiner's metrics become degenerate only at absolute zero and have non-vanishing scalar curvatures.Comment: LaTeX file, no figure

Effects of the second virial coefficient on the adiabatic lapse rate of dry atmospheres

We study the effect of the second virial coefficient on the adiabatic lapse rate of a dry atmosphere. To this end, we compute the corresponding adiabatic curves, the internal energy, and the heat capacity, among other thermodynamic parameters. We apply these results to Earth, Mars, Venus, Titan, and the exoplanet G1 851d, considering three physically relevant virial coefficients in each case: the hard-sphere, van der Waals, and the square-well potential. These examples illustrate under which atmospheric conditions the effect of the second virial coefficient is relevant. Taking the latter into account yields corrections towards the experimental values of the lapse rates of Venus and Titan in some instances.Comment: 12 pages, 8 figures. Comments are welcom

Adiabatic lapse rate of real gases

We derive a formula for the dry adiabatic lapse rate of atmospheres composed of real gases. We restrict our study to those described by a family of two-parameter cubic equations of state and the recent Guevara-Rodríguez noncubic equation. Since our formula depends on the adiabatic curves, we compute them all at once, considering molecules that can move, rotate, and vibrate, for any equation of state. To illustrate our results, we estimate the lapse rate of the troposphere of Titan, obtaining a better approximation to the observed data in some instances, when compared to the estimation provided by the virial expansion up to the third order.B.D. acknowledges support from the CONEX-Plus programme funded by the Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation program under Marie Sklodowska-Curie Grant No. 801538. J.E.R. acknowledges financial support from the Consejo de Ciencia y Tecnología del Estado de Puebla. This work has been supported by the Spanish Ministerio de Ciencia Innovación y Universidades-Agencia Estatal de Investigación under Grant No. PID2020-116567GB-C22

Composición para suplemento alimenticio

Composición para suplemento alimenticio. Composición que comprende una combinación extrusionada de semilla de lino, salvado de trigo y harina de girasol. Además, la presente invención se refiere al uso de dicha composición como suplemento alimenticio para animales, y la obtención, mediante el uso de dicho suplemento, de leche enriquecida en ácidos -linolénico y ruménico.Peer reviewedConsejo Superior de Investigaciones Científicas (España), LODYN SL, Institut de Recerca i Tecnologia Agroalimentàries (IRTA), Institució Catalana de Recerca i Estudis Avançats (ICREA)B1 Patente con informe sobre el estado de la ténic

A combination of metallomics and metabolomics studies to evaluate the effects of metal interactions in mammals. Application to Mus musculus mice under arsenic/cadmium exposure

Metals interactionsArsenicCadmiumMetallomicsMetabolomicsMus musculusMass spectrometryArsenic and cadmium are toxic metals of environmental significance with harmful effects on man. To study the toxicological and biochemical effects of arsenic/cadmium in mammals a combined metallomic and metabolomic approach has been developed, complemented with the measurement of biochemical parameters in blood and histopathological evaluation of liver injury in mice Mus musculus under exposure to both xenobiotics. Size-exclusion chromatography (SEC) was combined with affinity chromatography (AF) and ICP-MS detection using species unspecific isotopic dilution analysis (SUID) to characterize the biological effects of As/Cd on selenium containing proteins in the bloodstream of exposed mice. On the other hand, both direct infusion mass spectrometry (DIMS) and gas chromatography–mass spectrometry (GC–MS) provided information about changes in metabolites caused by metals. The results show that As/Cd exposure produces interactions in the distribution of both toxics between organs and plasma of mice and antagonistic interactions with selenium containing proteins in the bloodstream. Interplay with essential metabolic pathways, such as energy metabolism and breakdown of membrane phospholipids were observed, which are more pronounced under As/Cd exposure. In addition, heavy metal and metalloid causes differential liver injury, manifested by steatosis (non-alcoholic fatty liver disease, NAFLD) and infiltration of blood cells into the space of Disse. Biological significance This work presents new contributions in the study of arsenic/cadmium interactions in mice Mus musculus under controlled exposure. With the combination of metallomic and metabolomic approaches the traffic of As and Cd from liver to kidney by means of blood was observed and excretion of As (as arsenic metabolites) or Cd (as MTCd) is inhibited with the simultaneous administration of As/Cd, and these toxic elements have important influence in the levels of seleno-proteins in the plasma. In addition, the metabolomic approach reveals inhibition of different metabolic cycles such as tricarboxylic acid and phospholipid degradation that causes membrane damage and apoptosis that is histopathologically confirmed. This article is part of a Special Issue entitled: Environmental and structural proteomics.The authors thank the projects CTM2012-38720-G03-01 (Ministerio de Economia y Competitividad-Spain), P08-FQM-03554 and P09-FQM-04659 (Consejeria de Innovacion, Andalusian government). Miguel Angel Garcia Sevillano thanks the Ministerio de Educacion for a predoctoral scholarship

Effects of the second virial coefficient on the adiabatic lapse rate of dry atmospheres

We study the effect of the second virial coefficient on the adiabatic lapse rate of a dry atmosphere. To this end, we compute the corresponding adiabatic curves, the internal energy, and the heat capacity, among other thermodynamic parameters. We apply these results to Earth, Mars, Venus, Titan, and the exoplanet G1 851d, considering three physically relevant virial coefficients in each case: the hard-sphere, van der Waals, and the square-well potential. These examples illustrate under which atmospheric conditions the effect of the second virial coefficient is relevant. Taking the latter into account yields corrections towards the experimental values of the lapse rates of Venus and Titan in some instances

Analysis of Engine Thermal Effect on Electronic Control units for “Robot Fleets for Highly effective Agriculture and Forestry Management” (RHEA)

The procedures carried out in order to perform the analysis by engine thermal effect on the electronic control units installed on a ground robot fleet were studied in this work. The objective is to characterize the temperatures on the engine tractor environment for different tasks. In this way, it could be possible to estimate the environmental conditions that the cabinets will be exposed to. Those cabinets, in which the electronic controls of sensors, actuators and power supplies will be stored, will be located aboard the ground robot unit

Composición para suplemento alimenticio

Composición para suplemento alimenticio. Composición que comprende una combinación extrusionada de semilla de lino, salvado de trigo y harina de girasol. Además, la presente invención se refiere al uso de dicha composición como suplemento alimenticio para animales, y la obtención, mediante el uso de dicho suplemento, de leche enriquecida en ácidos -linolénico y ruménico.Peer reviewedConsejo Superior de Investigaciones Científicas (España), LODYN SL, Institut de Recerca i Tecnologia Agroalimentàries (IRTA), Institució Catalana de Recerca i Estudis Avançats (ICREA)B1 Patente con informe sobre el estado de la ténic

Composición para suplemento alimenticio

Composición para suplemento alimenticio. Composición que comprende una combinación extrusionada de semilla de lino, salvado de trigo y harina de girasol. Además la presente invención se refiere al uso de dicha composición como suplemento alimenticio para animales, y la obtención, mediante el uso de dicho suplemento, de leche enriquecida en ácidos -linolénico y ruménico.Peer reviewedConsejo Superior de Investigaciones Científicas (CSIC), Lodyn SL, Institut de Recerca I Tecnologia Agroalimentàries (IRTA), Institució Catalana de Recerca i Estudis Avancats (ICREA)A1 Solicitud de patentes con informe sobre el estado de la técnic