Spin filtering induced by a magnetic insulator stripe on graphene

Proximity exchange interaction between graphene electrons and nearby magnetic insulators paves the way to create spin-polarised currents for spintronics applications. Different ferro- and ferrimagnetic insulators, such as europium chalcogenides, yttrium iron garnet and cobalt ferrite, have been proposed in the literature to induce magnetic correlations in graphene. We theoretically study electronic transport properties of graphene in close proximity to a strip of a magnetic insulator, when the system is connected to nonmagnetic source and drain leads. To this end, we describe graphene electrons by means of an effective Hamiltonian whose model parameters are extracted from first-principle calculations. We compare the spin-polarization of the electron current calculated for a number of different magnetic insulators, aiming at elucidating the effects of the various model parameters on the efficiency of the device. In particular, we demonstrate that the polarization of the electric current across the device can be tuned by the source-drain voltage. We conclude that the heterostructures based on europium chalcogenides are ideal candidates to achieve high polarisation at low temperature

Silencing hepatic MCJ attenuates non-alcoholic fatty liver disease (NAFLD) by increasing mitochondrial fatty acid oxidation

Nonalcoholic fatty liver disease (NAFLD) is considered the next major health epidemic with an estimated 25% worldwide prevalence. No drugs have yet been approved and NAFLD remains a major unmet need. Here, we identify MCJ (Methylation-Controlled J protein) as a target for non-alcoholic steatohepatitis (NASH), an advanced phase of NAFLD. MCJ is an endogenous negative regulator of the respiratory chain Complex I that acts to restrain mitochondrial respiration. We show that therapeutic targeting of MCJ in the liver with nanoparticle- and GalNAc-formulated siRNA efficiently reduces liver lipid accumulation and fibrosis in multiple NASH mouse models. Decreasing MCJ expression enhances the capacity of hepatocytes to mediate beta -oxidation of fatty acids and minimizes lipid accumulation, which results in reduced hepatocyte damage and fibrosis. Moreover, MCJ levels in the liver of NAFLD patients are elevated relative to healthy subjects. Thus, inhibition of MCJ emerges as an alternative approach to treat NAFLD. Non-alcoholic fatty liver (NAFLD) disease causes degeneration of the liver, affects about 25% of people globally, and has no approved treatment. Here, the authors show that the therapeutic siRNA-driven silencing of MCJ in the liver is an effective and safe treatment for NAFLD in multiple mouse models.We thank Douglas Taatjes and Nicole Bouffard for help with confocal microscopy analysis (Microscopy Imaging Center) at the University of Vermont. We also thank the University of Vermont Medical Center's Department of Pathology and Laboratory Medicine Histology and Clinical Laboratories for assistance with liver section staining and AST/ALT measurement, respectively. This work was supported by NIH STTR R41DK112429 (M.R.), NIH PO GM103496 (M.R.), Mitotherapeutix LLC (M.R., K.F, and M.L.M.-C.), MINECO/Feder SAF2015-65327-R and RTI2018-096494-B-100 (J.A.), MINECO/Feder SAF2017-87301-R (M.L.M-C.), BIOEF (M.L.M.-C.), EITB Maratoia BIO15/CA/014 (M.L.M-C), BBVA (M.L.M.-C.), La Caixa Foundation (M.L.M.-C.), Basque Country Health Department 2013111114 (M.L.M-C), MINECO/Feder SAF2015-64352-R (P.A.) and MINECO-Feder RTI2018-095134-B-100 (P.A.). ISCIII-Feder PI17/00535 (C.G.-M.), ISCIII-Feder CP14/00181, and PI16/00823 (A.G-R.), and Francisco Cobos Foundation (A.G.-R.). CIC bioGUNE is the recipient of a Severo Ochoa Excellence Accreditation (SEV-2016-0644) by the Ministry of Science, Innovation and Universities

The time-dependent canonical formalism: Generalized harmonic oscillator and the infinite square well with a moving boundary

In this paper a systematic formalism for dealing with non-relativistic time-dependent quantum Hamiltonians is presented. The starting point is the well-known Lewis and Riesenfeld idea which involves the construction of an invariant operator I(x,t) which defines both the dynamics of the physical system and the canonical formalism that has to be used in order to obtain a consistent theoretical framework. In order to exhibit the full power of the formalism we discuss two examples: the generalized harmonic oscillator and the infinite square well with a moving boundary. As the first example has already been analyzed by the present authors from other different points of view, we are able to compare the results of the canonical formalism with these other approaches and, as it was expected, we obtain identical descriptions of this physical system. After this, we turn to the case of the square well with a moving boundary. The main surprise is that in order to obtain consistency with the formalism an effective interaction appears which seems to be due to the time dependence of the boundary. Also consistency with the principle of minimal coupling and gauge invariance is obtained just by using this canonical operator formalism. Finally some interesting physical applications are suggested and discussed

Europhysics Letters

. -- In this paper a systematic formalism for dealing with non-relativistic timedependent quantum Hamiltonians is presented. The starting point is the well-known Lewis and Riesenfeld idea which involves the construction of an invariant operator I(x, t) which defines both the dynamics of the physical system and the canonical formalism that has to be used in order to obtain a consistent theoretical framework. In order to exhibit the full power of the formalism we discuss two examples: the generalized harmonic oscillator and the infinite square well with a moving boundary. As the first example has already been analyzed by the present authors from other di#erent points of view, we are able to compare the results of the canonical formalism with these other approaches and, as it was expected, we obtain identical descriptions of this physical system. After this, we turn to the case of the square well with a moving boundary. The main surprise is that in order to obtain consistency with the for..