Lithium insertion materials have attracted attention among electrochemists and battery researchers because of their potential use for both positive and negative electrodes for lithium-ion (shuttlecock) batteries. 1-3 The negative-electrode materials are usually carbon on which the side reactions of the decomposition of organic solvents due to a catalytic effect of carbon proceed during charge and discharge in addition to lithium-ion insertion and extraction reactions. 4-6 Some of them show anomalous expansion in the negativeelectrode thickness, especially during the first charge and discharge, so-called breaking-in process. These effects can be minimized by selecting appropriate carbon materials together with electrolyte and by optimizing the electrode composition and processing methods, and cycle life can be extended to a quite high level. However, we need to explore new insertion materials in order to advance beyond current lithium-ion batteries. A final goal of our basic research is to design so-called zero-strain insertion materials with which one can expect excellent cycle life and also to control cell chemistry to give ultimate reliability and safety for the next lithium-ion batteries. In order to approach such a final goal, we have planned systematic studies on the effect of partial metal substitution on the crystal structure, electrochemical reactivity, solid-state redox potential, and insertion scheme.In this paper we report the results on Li [CrTi]O 4 , which is isostructural with Li[Li 0.33 Ti 1.67 ]O 4 , 7 and discuss the differences and similarities between the solid-state electrochemistry of Li[Li 0.33 Ti 1.67 ]O 4 and that of Li[CrTi]O 4 . Experimental Li[CrTi]O 4 was prepared from LiOHиH 2 O (Kishida ChemicalCo., Ltd., Japan), Cr 2 O 3 (Wako Pure Chemical Co., Ltd., Japan), and TiO 2 (anatase; Kishida Chemical Co., Ltd.). The reaction mixture was ground in an alumina mortar with a pestle by hand and pressed into pellets (23 mm diam and ca. 5 mm thick.). The pellets were reacted at 800ЊC for 20 h in air. The reaction product was ground and stored in a desiccator over blue silica-gel. The prepared sample was characterized by X-ray diffraction (XRD) using an X-ray diffractometer (XD-3A, Shimadzu Corp., Japan) with Cu K␣ radiation (30 kV, 20 mA). The optical system was adjusted to be a line focus. The system was equipped with a diffracted graphite monochromator to select the copper K␣ line from the diffracted beam. The X-ray system was calibrated using Si (a ϭ 5.4308 Å). Prior to the XRD measurements, the electrode samples (15 ϫ 20 mm) were covered with polyethylene film and heat-sealed to prevent the reactions of the reduced or oxidized samples of Li[CrTi]O 4 with moist air.Details of the electrochemical cells and data acquisition system used in this study were described previously. 8,9 Acoustic events inside the cells were also measured by a method described previously. [10][11][12] The composition of the electrode mix was 85 wt % Li[CrTi]O 4 (or Li[Li 0.33 Ti 1.67 ]O 4 ), 10 wt % acetylene black, a...

No abstract

No abstract

Empagliflozin, a sodium-glucose co-transporter 2 inhibitor developed, has been shown to reduce cardiovascular events in patients with type 2 diabetes and established cardiovascular disease. Several studies have suggested that empagliflozin improves the cardiac energy state which is a partial cause of its potency. However, the detailed mechanism remains unclear. To address this issue, we used a mouse model that enabled direct measurement of cytosolic and mitochondrial ATP levels. Empagliflozin treatment significantly increased cytosolic and mitochondrial ATP levels in the hearts of db/db mice. Empagliflozin also enhanced cardiac robustness by maintaining intracellular ATP levels and the recovery capacity in the infarcted area during ischemic-reperfusion. Our findings suggest that empagliflozin enters cardiac mitochondria and directly causes these effects by increasing mitochondrial ATP via inhibition of NHE1 and Nav1.5 or their common downstream sites. These cardioprotective effects may be involved in the beneficial effects on heart failure seen in clinical trials.

No abstract