Kazan Federal University

About: Kazan Federal University is a education organization based out in Kazan’, Russia. It is known for research contribution in the topics: Population & Chemistry. The organization has 9868 authors who have published 14390 publications receiving 135726 citations. The organization is also known as: Kazan (Volga region) Federal University & Kazan State University.

Superconducting triplet spin valve

Abstract: We study the critical temperature T c of SFF trilayers (S is a singlet superconductor, F is a ferromagnetic metal), where the long-range triplet superconducting component is generated at noncollinear magnetizations of the F layers. We demonstrate that T c can be a nonmonotonic function of the angle α between the magnetizations of the two F layers. The minimum is achieved at an intermediate α, lying between the parallel (P, α = 0) and antiparallel (AP, α = π) cases. This implies a possibility of a “triplet” spin-valve effect: at temperatures above the minimum T Tr but below T P and T AP , the system is superconducting only in the vicinity of the collinear orientations. At certain parameters, we predict a reentrant T c (α) behavior. At the same time, considering only the P and AP orientations, we find that both the “standard” (T P < T AP ) and “inverse” (T P > T AP ) switching effects are possible depending on parameters of the system.

Equation of state constraints for the cold dense matter inside neutron stars using the cooling tail method

Abstract: The cooling phase of thermonuclear (type-I) X-ray bursts can be used to constrain neutron star (NS) compactness by comparing the observed cooling tracks of bursts to accurate theoretical atmosphere model calculations. By applying the so-called cooling tail method, where the information from the whole cooling track is used, we constrain the mass, radius, and distance for three different NSs in low-mass X-ray binaries 4U 1702−429, 4U 1724−307, and SAX J1810.8−260. Care is taken to use only the hard state bursts where it is thought that the NS surface alone is emitting. We then use a Markov chain Monte Carlo algorithm within a Bayesian framework to obtain a parameterized equation of state (EoS) of cold dense matter from our initial mass and radius constraints. This allows us to set limits on various nuclear parameters and to constrain an empirical pressure-density relationship for the dense matter. Our predicted EoS results in NS a radius between 10.5−12.8 km (95% confidence limits) for a mass of 1.4 M ⊙ , depending slightly on the assumed composition. Because of systematic errors and uncertainty in the composition, these results should be interpreted as lower limits for the radius.

Human Gut Symbiont Roseburia hominis Promotes and Regulates Innate Immunity

Abstract: Acknowledgments The authors would like to thank Andrew Gewirtz (Georgia State University, Atlanta, GA, USA) and Adam Cunningham (University of Birmingham, Edgbaston, Birmingham, UK) for generously providing the germ-free and conventional TLR5KO mice, respectively. The authors also wish to acknowledge a significant contribution to the inception of the work, experimental work, interpretation of results, and writing of the manuscript by Denise Kelly, as well as the support from RESAS (Rural and Environmental Science and Analytical Services) of the Scottish Government. EM and VF were supported by the Marie Curie Initial training network Fellowships funded by the EU (grant #215532). The authors acknowledge a generous support of Prof. Harry Flint and Dr. Sylvia Duncan in the microbiological part of this work. The skilled technical support of Gillian Campbell and Pauline Young at RINH Genomics is also gratefully acknowledged.

The effect of hydrostatic pressure up to 1.61 GPa on the Morin transition of hematite‐bearing rocks: Implications for planetary crustal magnetization

Abstract: We present new experimental data on the dependence of the Morin transition temperature (TM) on hydrostatic pressure up to 1.61 GPa, obtained on a well-characterized multidomain hematite-bearing sample from a banded iron formation. We used a nonmagnetic high-pressure cell for pressure application and a Superconducting Quantum Interference Device magnetometer to measure the isothermal remanent magnetization (IRM) under pressure on warming from 243 K to room temperature (T0). IRM imparted at T0 under pressure in 270 mT magnetic field (IRM270mT) is not recovered after a cooling-warming cycle. Memory effect under pressure was quantified as IRM recovery decrease of 10%/GPa. TM, determined on warming, reaches T0 under hydrostatic pressure 1.38–1.61 GPa. The pressure dependence of TM up to 1.61 GPa is positive and essentially linear with a slope dTM/dP = (25 ± 2) K/GPa. This estimate is more precise than previous ones and allows quantifying the effect of a pressure wave on the upper crust magnetization, with special emphasis on Mars.