RESUMEN
Two-dimensional (2D) carbon materials integrated with planar tetracoordinate carbon (ptC) and negative Poisson's ratio (NPR) provide a cornerstone for constructing multifunctional energy-storage devices. As a typical 2D carbon material, the pristine graphene is chemically inert, hindering its application in metal-ion batteries. Introducing the ptC in graphene can break the extended conjugation of π-electrons and lead to an enhanced surface reactivity. Inspired by the unique geometry of [4.6.4.6] fenestrane skeleton with ptC, we theoretically design a ptC-containing 2D carbon allotrope, namely THFS-carbon. It is intrinsically metallic with excellent dynamical, thermal, and mechanical stabilities. The Young's modulus along the x direction (311.37 N m-1) is comparable to that of graphene. Intriguingly, THFS-carbon possesses an in-plane half-NPR distinct from most other 2D crystals. As a promising anode for sodium-ion batteries, THFS-carbon delivers an ultra-high theoretical storage capacity (2233 mA h g-1), a low diffusion energy barrier (0.03-0.05 eV), a low open-circuit voltage (0.14-0.40 V), and a good reversibility for Na insertion/extraction.
RESUMEN
Sodium-ion batteries (SIBs) have attracted great attention owing to their low cost and inherent safety. High-performance anode materials for SIBs should possess intrinsically metallic characteristic and be composed of non-toxic, earth abundant, and lightweight elements. We predict a two-dimensional Mg material (named magnesene) to be an excellent anode material, which can meet these design requirements. It is demonstrated to be stable in terms of the cohesive energy, phonon spectrum, ab initio molecular dynamics simulation, and elastic constants. The magnesene monolayer exhibits good SIB performances, including a high storage capacity of 551.3 mA h g-1, low diffusion energy barrier (0.16-0.19 eV), low open-circuit voltage (0.71-0.82 V), and small volume change (4.7%). Moreover, graphene or h-BN on top of magnesene could serve as a protective cover to preserve the performances of pristine magnesene, such as metallicity, strong Na adsorption capability, and fast ionic mobility. These intriguing theoretical findings make magnesene a promising anode material for SIBs.
RESUMEN
Atrial structural and electrical remodelling play important roles in atrial fibrillation (AF). Sacubitril/valsartan attenuates cardiac remodelling in heart failure. However, the effect of sacubitril/valsartan on AF is unclear. The aim of this study was to evaluate the effect of sacubitril/valsartan on atrial electrical and structural remodelling in AF and investigate the underlying mechanism of action. Thirty-three rabbits were randomized into sham, RAP, and sac/val groups. HL-1 cells were subjected to control treatment or rapid pacing with or without LBQ657 and valsartan. Echocardiography, atrial electrophysiology, and histological examination were performed. The concentration of Ca2+ and expression levels of calcineurin, NFAT, p-NFAT, Cav1.2, collagen â and â ¢, ANP, BNP, CNP, NT-proBNP, and ST2 in HL-1 cells, and IcaL in left atrial cells, were determined. We observed that compared to that in the sham group, the atrium and right ventricle were enlarged, myocardial fibrosis was markedly higher, AF inducibility was significantly elevated, and atrial effective refractory periods were shortened in the RAP group. These effects were significantly reversed by sacubitril/valsartan. Compared to that in the sham group, collagen â and â ¢, NT-proBNP, ST2, calcineurin, and NFAT were significantly up-regulated, while p-NFAT and Cav1.2 were down-regulated in the RAP group, and sacubitril/valsartan inhibited these changes. Ca2+ concentration increased and ICaL density decreased in in vivo and in vitro AF models, reversed by sacubitril/valsartan. Sacubitril/valsartan attenuates atrial electrical remodelling and ameliorates structure remodelling in AF. This study paves the way for the possibility of clinical use of sacubitril/valsartan in AF patients.
