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In recent years, aqueous zinc-ion batteries (AZIBs) have been rapidly developed and are favored by the public as a future large-scale energy storage system. Manganese-based compounds with multiple valence states and high electrochemical activity have been extensively investigated as cathodes for AZIBs due to their abundant reserves and high theoretical capacity. However, some problems hinder their application in AZIBs, such as low conductivity and sluggish kinetics. Defect engineering has been verified as an effective method to alleviate the above limitations. In this work, manganese oxide with oxygen defects (Od-MnO2) was successfully constructed and characterized by XRD, SEM, XPS, and TEM. Surface oxygen defects increase ion active transfer sites and improve electronic conductivity. Compared with MnO2, Od-MnO2 produced more localized electrons which could improve the electrochemical performance as cathodes for AZIBs. The discharge specific capacity of Od-MnO2 reaches 307.9 mAh g−1 in the first cycle at a current density of 0.1 A g−1 and maintains at 100.5 mAh g−1 at a current density of 10.0 A g−1. After 1000 cycles, the discharge specific capacity can still reach 82.5 mAh g−1 and the capacity retention rate is 82.1%. [ABSTRACT FROM AUTHOR]

In this paper, NaSn0.02Ti1.98(PO4)3/C composite material was prepared by spray drying method combined with high-temperature calcination, which can improve the electrochemical performance of NaTi2(PO4)3. The doping of Sn4+ increases the lattice spacing of NaTi2(PO4)3, thereby accelerating the diffusion coefficient of Na+. The carbon doped on NaTi2(PO4)3 reduces the charge transfer impedance and enhances the ion diffusion coefficient. As a result, NaSn0.02Ti1.98(PO4)3/C exhibits improved electrochemical performance. The specific capacity for the initial discharge of NaSn0.02Ti1.98(PO4)3/C at 1C, 5C, 10C and 20C rates are 108 mAh/g, 86 mAh/g, 76.3 mAh/g, and 71.4 mAh/g, respectively. After 1400 cycles at 10C, the capacity of the material decreases to 64.3 mAh/g, with a capacity retention rate of 84.2%. Therefore, NaSn0.02Ti1.98(PO4)3/C exhibits fast charge/discharge performance as well as cycling stability. [ABSTRACT FROM AUTHOR]

Background: In recent years, the mechanistic interaction between the brain and heart has been explored in detail, which explains the effects of brain injuries on the heart and those of cardiac dysfunction on the brain. Brain injuries are the predominant cause of post-stroke deaths, and cardiac dysfunction is the second leading cause of mortality after stroke onset. Summary: Several studies have reported the association between brain injuries and cardiac dysfunction. Therefore, it is necessary to study the influence on the heart post-stroke to understand the underlying mechanisms of stroke and cardiac dysfunction. This review focuses on the mechanisms and the effects of cardiac dysfunction after the onset of stroke (ischemic or hemorrhagic stroke). Key Messages: The role of the site of stroke and the underlying mechanisms of the brain-heart axis after stroke onset, including the hypothalamic-pituitary-adrenal axis, inflammatory and immune responses, brain-multi-organ axis, are discussed. [ABSTRACT FROM AUTHOR]

The laminate is essentially bonded together to form the individual laminate by the matrix, any delamination of the laminate must be initiated from a matrix failure. Based on this viewpoint, the initiation of laminate delamination was predicted through analyzing the stresses of the matrix. A three-dimensional finite element method is used to calculate the stress field of a symmetrically laminated plate under an axial load. A convergence study was performed and an average stress method was proposed to solve the singularity problem. Then the internal stresses in the fiber and matrix were determined in terms of the bridging micromechanics model. Finally, a Mohr criterion was used to detect the failure of matrix. T800/914 angle-plied laminates were considered. The results show that this approach is able to correlate reasonably with the available experimental data.

In this work, the Sn-doped titanium niobate Snx-TiNb2O7 (Snx-TNO, x = 0.005, 0.01, 0.02, 004, 0.06, 0.08) samples have been fabricated through a solid-state reaction method with the aim of investigating the effect of Sn4+ doping on the electrochemical performance enhancement of TiNb2O7 (TNO). Elemental mapping image indicates that Sn is successfully doped and evenly distributed in the TNO sample. XRD patterns show that the doping of Sn4+ can slightly increase the lattice spacing of TNO materials, which can increase the diffusion coefficient of Li+ ions due to the ion-size effect. The specific capacity, capacity retention, long cycle performance, and rate performance of Snx-TNO materials are all superior to those of TNO, and Sn0.01-TNO has the best performance. Compared with TNO, Sn0.01-TNO exhibited a smaller polarization potential, indicating that the doping of tin elements resulted in a more efficient kinetic reaction process and a higher redox reversibility. The EIS results further verify that the Sn0.01-TNO material has a lower charge transfer impedance and a higher ion diffusion coefficient compared to the TNO material, resulting in better electrochemical performance of the Sn0.01-TNO material. The strategy of appropriate metal doping can improve the intrinsic electronic/ionic conductivity and structural stability of the material, providing new insights for the development of advanced high-power electrode materials. [ABSTRACT FROM AUTHOR]

Congenital insensitivity to pain with anhidrosis (CIPA) is a rare disease which mainly affects infants, children and adolescents. As an autosomal recessive disorder, CIPA is also known as familial autonomic dysfunction type 2. The diagnosis of CIPA mainly relies on clinical observation and genetic testing. Currently there is lack of effective treatment, and it is mainly treated by cooling, anti-inflammatory and strengthened guardianization. This article has reviewed the literature and summarized the research on CIPA and progress made in its diagnosis and treatment, with an aim to improve the understanding of this disorder.