Magnetic anisotropies and its optical manipulation in epitaxial bismuth ferrite/ferromagnet heterostructure

© 2018 Elsevier B.V. Exchange-coupled BiFeO3/ferromagnet thin film heterostructures are promising for a fast and power efficient control of magnetization of the ferromagnetic layer. In the paper, the results of the study of magnetic properties of the epitaxial Fe2B/BiFeO3heterostructure on (0 0 1)-SrTiO3substrate with ferromagnetic resonance (FMR) spectroscopy are presented. The hierarchy of magnetic anisotropies that determine the angular variation of the resonance field in-plane and in-/out-of the plane of the system include the tetragonal four-fold and uniaxial terms for the Fe2B layer, uniaxial term for antiferromagnetic BiFeO3layer and the exchange coupling at the interface. We find out that the exchange bias direction can be switched by a strong enough applied magnetic field. Both the exchange bias and an in-plane FMR resonance field of the heterostructure are strongly affected by the illumination with λ = 405 nm light. An optical tunability of the exchange bias and ferromagnetic resonance fields of the heterostructure has been demonstrated

The ER Stress/UPR axis in chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis

Cellular protein homeostasis in the lungs is constantly disrupted by recurrent exposure to various external and internal stressors, which may cause considerable protein secretion pressure on the endoplasmic reticulum (ER), resulting in the survival and differentiation of these cell types to meet the increased functional demands. Cells are able to induce a highly conserved adaptive mechanism, known as the unfolded protein response (UPR), to manage such stresses. UPR dysregulation and ER stress are involved in numerous human illnesses, such as metabolic syndrome, fibrotic diseases, and neurodegeneration, and cancer. Therefore, effective and specific compounds targeting the UPR pathway are being considered as potential therapies. This review focuses on the impact of both external and internal stressors on the ER in idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) and discusses the role of the UPR signaling pathway activation in the control of cellular damage and specifically highlights the potential involvement of non-coding RNAs in COPD. Summaries of pathogenic mechanisms associated with the ER stress/UPR axis contributing to IPF and COPD, and promising pharmacological intervention strategies, are also presented

The c.-190 C>A transversion in promoter region of protamine1 gene as a genetic risk factor for idiopathic oligozoospermia

The genome condensation in the sperm head is resulted with replacing of histones by protamines during spermatogenesis. It is reported that defects in the protamine 1 (PRM1) and/or 2 (PRM2) genes cause male infertility. Located on chromosome 16 (16p13.2) these genes contain numerous unstudied single nucleotide polymorphisms. This study aimed to investigate the association of c.�190 C>A and g.298 G>C transversions that respectively occur in PRM1 and PRM2 genes with idiopathic oligozoospermia. In a case�control study, we collected blood samples from 130 idiopathic oligozoospermia and 130 fertile men. Detection of c.�190 C>A and g.298 G>C polymorphisms performed by direct sequencing and PCR�RFLP methods respectively. An in silico analysis was performed by ASSP, NetGene 2, and PNImodeler online web servers. Our data revealed that g.298 G>C transversion in PRM2 was not associated with oligozoospermia (P > 0.05). Whereas, �190CA and �190AA genotypes in PRM1 gene were associated significantly with increased risk of oligozoospermia (P = 0.0017 and 0.0103, respectively). Also carriers of A allele (CA+AA) for PRM1 c.�190 C>A were at a high risk for oligozoospermia (OR 3.2440, 95 CI 1.8060�5.8270, P = 0.0001). Further, in silico analysis revealed that c.�190 C>A transversion may alter transcription factor interactions with the promoter region of PRM1. The results revealed that the c.�190 C>A transversion may involve in the susceptibility for oligozoospermia and could be represented as a noninvasive molecular marker for genetic diagnosis of idiopathic oligozoospermia. © 2016, Springer Science+Business Media Dordrecht

Magnetic anisotropies and its optical manipulation in epitaxial bismuth ferrite/ferromagnet heterostructure

© 2018 Elsevier B.V. Exchange-coupled BiFeO3/ferromagnet thin film heterostructures are promising for a fast and power efficient control of magnetization of the ferromagnetic layer. In the paper, the results of the study of magnetic properties of the epitaxial Fe2B/BiFeO3heterostructure on (0 0 1)-SrTiO3substrate with ferromagnetic resonance (FMR) spectroscopy are presented. The hierarchy of magnetic anisotropies that determine the angular variation of the resonance field in-plane and in-/out-of the plane of the system include the tetragonal four-fold and uniaxial terms for the Fe2B layer, uniaxial term for antiferromagnetic BiFeO3layer and the exchange coupling at the interface. We find out that the exchange bias direction can be switched by a strong enough applied magnetic field. Both the exchange bias and an in-plane FMR resonance field of the heterostructure are strongly affected by the illumination with λ = 405 nm light. An optical tunability of the exchange bias and ferromagnetic resonance fields of the heterostructure has been demonstrated