Electrochemically Inert Li2MnO3: The Key to Improving the Cycling Stability of Li-Rich Manganese Oxide Used in Lithium-Ion Batteries.

Lithium-rich manganese oxide is a promising candidate for the next-generation cathode material of lithium-ion batteries because of its low cost and high specific capacity. Herein, a series of xLi2MnO3·(1 - x)LiMnO2 nanocomposites were designed via an ingenious one-step dynamic hydrothermal route. A high concentration of alkaline solution, intense hydrothermal conditions, and stirring were used to obtain nanoparticles with a large surface area and uniform dispersity. The experimental results demonstrate that 0.072Li2MnO3·0.928LiMnO2 nanoparticles exhibit a desirable electrochemical performance and deliver a high capacity of 196.4 mAh g-1 at 0.1 C. This capacity was maintained at 190.5 mAh g-1 with a retention rate of 97.0% by the 50th cycle, which demonstrates the excellent cycling stability. Furthermore, XRD characterization of the cycled electrode indicates that the Li2MnO3 phase of the composite is inert, even under a high potential (4.8 V), which is in contrast with most previous reports of lithium-rich materials. The inertness of Li2MnO3 is attributed to its high crystallinity and few structural defects, which make it difficult to activate. Hence, the final products demonstrate a favorable electrochemical performance with appropriate proportions of two phases in the composite, as high contents of inert Li2MnO3 lower the capacity, while a sufficient structural stability cannot be achieved with low contents. The findings indicate that controlling the composition through a dynamic hydrothermal route is an effective strategy for developing a Mn-based cathode material for lithium-ion batteries.

Temporal and spatial expression of AIF in the mouse uterus during early pregnancy.

Apoptosis-inducing factor (AIF) is a phylogenetically old, bifunctional protein with a pro-apoptotic function and redox activity. AIF regulates apoptosis and also plays a role in the defense against stress depending on its subcellular localization. Embryo implantation is a complicated process, in which an activated blastocyst interacts with a receptive uterus. The expression and regulation of AIF were investigated in this study in the mouse uterus during early pregnancy, pseudopregnancy, delayed implantation, artificial decidualization and under hormonal treatment using in situ hybridization, immunohistochemistry and real-time PCR. During early pregnancy, temporally and spatially regulated patterns of AIF expression were found in the mouse uterus; AIF expression in the luminal epithelium and glandular epithelium is regulated by steroid hormones; AIF mRNA expression in the stroma is influenced by the active blastocyst; and AIF protein was found to be located in the cytoplasm rather than the nucleus through confocal microscope. Our data suggest that AIF might play an important role during mouse embryo implantation and that the role of AIF might be implemented through its physiological activity rather than through its pro-apoptotic function in the mouse uterus during this period.

[A new form of cell death: Parthanatos].

Parthanatos is a form of cell death, which often occurs in many diseases such as stroke, Parkinson's disease, heart attack, diabetes, and ischemia reperfusion injury. In a cell, the activation of PARP-1 caused by excitotoxicity leads to Parthanatos, which is also known as PARP-1-dependent cell death. There are multiple cell signaling pathways involved in the process of Parthanatos, which have not been fully understood. The main focus of this article is underlying molecular mechanisms of Parthanatos.