Designing potential anodes for sodium-ion battery with both remarkable durability and high-rate capability has captured enormous attention so far. The engineering of size and morphology is deemed as an effective manner to boost the electrochemical properties. Owing to the anisotropic self-assembly of iron selenide, rod-like FeSe 2 coates with nitrogen-doped carbon is prepared through the thermal reaction of Prussian blue with selenium. Notably, the cyano groups are effectively transformed into N-doped carbon with FeNC bonds, which uniformly coats FeSe 2 , prompting Na + transportations. Interestingly, the particle size is tailored by heating rates, along with increased carbon content, leading to broadened energy levels for redox reaction. Bestowed by these advantages, the FeSe 2 /N-C as Na-storage anode delivers impressive electrochemical properties. Even at a rather high rate of 10.0 A g −1 , a considerable capacity of 308 mAh g −1 is yielded over 10 000 loops. Supported by the detailed analysis of kinetic features, reduced size of particles could bring about the enhanced contributions of pseudocapacitive and quickening rate of ions transferring. The phase evolutions are further investigated by in situ EIS and ex-situ technologies. The work is expected to provide a new strategy to prepare metal-selenide with controllable size and induce the faster kinetic of high-rate materials.

As a result of its high‐energy density, metal–selenides have demanded attention as a potential energy‐storage material. But they suffer from volume expansion, dissolved poly‐selenides and sluggish kinetics. Herein, utilizing' thermal selenization via the Kirkendall effect, microspheres of NiSe2 confined by carbon are successfully obtained from the self‐assembly of Ni‐precursor/PPy. The derived hierarchical hollow architecture increases the active defects for sodium storage, while the existing double N‐doped carbon layers significantly alleviate the volume swelling. As a result, it shows ultrafast rate capability, delivering a stable capacity of 374 mAh g−1, even after 3000 loops at 10.0 A g−1. These remarkable results may be ascribed to the NiOC bonds on the interface of NiSe2 and the carbon film, which leads to the faster transfer of ions, the effective trapping of poly‐selenide, and the highly reversible conversion reaction. The kinetic analysis of cyclic voltammetry (CV) demonstrates that the electrochemical process is mainly dominated by pseudocapacitive behaviors. Supported by the results of electrochemical impedance spectroscopy (EIS), it is confirmed that the solid–electrolyte interface films are reversibly formed/decomposed during cycling. Given this, this elaborate work might open up a potential avenue for the rational design of metal‐sulfur/selenide anodes for advanced battery systems.

Hydroxyapatite (HA) is an attractive bioceramic for hard tissue repair and regeneration due to its physicochemical similarities to natural apatite. However, its low fracture toughness, poor tensile strength and weak wear resistance become major obstacles for potential clinical applications. One promising method to tackle with these problems is exploiting graphene and its derivatives (graphene oxide and reduced graphene oxide) as nanoscale reinforcement fillers to fabricate graphene-based hydroxyapatite composites in the form of powders, coatings and scaffolds. The last few years witnessed increasing numbers of studies on the preparation, mechanical and biological evaluations of these novel materials. Herein, various preparation techniques, mechanical behaviors and toughen mechanism, the in vitro/in vivo biocompatible analysis, antibacterial properties of the graphene-based HA composites are presented in this review.

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Mostly reported MoSe2 suffered from easily stacking problem, volume expansion and relative low capacity. From the experience of Li/Na-Se batteries, the exfoliated and encapsulated MoSe2 inside carbon nanospheres with C-O-Mo bonds and large layer distance (0.89 nm) are successfully constructed. This unique effective structure has C-O-Mo bonding allowing high conductivity across the Se-O insulation layer and promoting its reversible conversion. The first-principles calculations demonstrated that the frontier molecular orbitals of C-O-Mo interface structure are mainly localized on the MoSe2 sheet fragment with an appropriate HOMO-LUMO gap (< 4eV),suggesting its good stability and conductivity. Utilized as anodes for LIBs allows a Li-storage capacity to be realized of 1208 mAh g -1 after 150 cycles at 1.0 A g -1 and 519 mAh g -1 after 200 cycles at 4.0 A g -1 . The Na-storage capacity is found to be 543, 491 mAh g -1 after 120 cycles at 0.1, 1.0 A g -1 . Focusing on the analysis of CV, the reducing particle may improve the capacitive behaviors, further resulting the high-rate performance. Ex-situ techniques demonstrated that the emerging Se was constrained uniformly. The controlling of by-product Se plays a key role in achieving a high rate 2 capacity and cycling stability, and opens up a potential avenue for these metal-selenide anodes designs for battery storage systems.

Sublethal hypoxic or ischemic events can improve the tolerance of tissues, organs, and even organisms from subsequent lethal injury caused by hypoxia or ischemia. This phenomenon has been termed hypoxic or ischemic preconditioning (HPC or IPC) and is well established in the heart and the brain. This review aims to discuss HPC and IPC with respect to their historical development and advancements in our understanding of the neurochemical basis for their neuroprotective role. Through decades of collaborative research and studies of HPC and IPC in other organ systems, our understanding of HPC and IPC-induced neuroprotection has expanded to include: early- (phosphorylation targets, transporter regulation, interfering RNA) and late- (regulation of genes like EPO, VEGF, and iNOS) phase changes, regulators of programmed cell death, members of metabolic pathways, receptor modulators, and many other novel targets. The rapid acceleration in our understanding of HPC and IPC will help facilitate transition into the clinical setting.

Sodium-ion batteries (SIBs), as the promising commercial energy system, are restricted by their sluggish kinetics and low sodium-ion storage. Metal selenide possesses good conductivity and capacity but still suffers from the stacked problem and volume expansion. Significantly, CoSe/C is successfully prepared with the assistance of citric acid as both a chelating agent and carbon precursor, displaying that cobblestone-like nanospheres with the radii (<25 nm) distribute uniformly in the carbon matrix. It is expected that the established Co-O-C bonds enhance the stability of the structure with faster ion shuttling. With the available electrolyte (NaCFSO/diethylene glycol dimethyl ether) in a potential window range from 0.5 to 3.0 V, the as-obtained sample shows the ultralong lifespan at 4.5 A g, retaining a capacity of 345 mA h g after 10 000 cycles. From the detailed kinetic analysis, it is clear that the surface-controlled electrochemical behavior mainly contributes to the excellent large-current cycling stability and Na storage capacity. The ex situ results support that the crystal and morphological structure remains stable. This work is anticipated to enhance the in-depth understanding of the CoSe/C anode and supply a facile manner to obtain electrode materials for SIBs.

Moyamoya disease is characterized by progressive stenosis or occlusion of the intracranial portion of the internal carotid artery and their proximal branches, resulting in ischemic or hemorrhagic stroke with high rate of disability and even death. So far, available treatment strategies are quite limited, and novel intervention method is being explored. This review encapsulates current advances of moyamoya disease on the aspects of epidemiology, etiology, clinical features, imaging diagnosis and treatment. In addition, we also bring forward our conjecture, which needs to be testified by future research.