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Solid solutions of Sn-Si derivatives with an LGPS (Li10GeP2S12)-type structure are synthesized by a solid-state reaction in the Li3PS4-Li4SnS4-Li4SiS4 quasi-ternary system. The monophasic region of the LGPS-type structure deviates from the tie line between Li10SiP2S12 and Li10SnP2S12, and the composition of the solid solution is determined to be -0.1 ≤ δ ≤ 0.5 and 0 ≤ y ≤ 1.0 in Li10+δ[SnySi1-y]1+δP2-δS12 (0.50 ≤ x ≤ 0.7 and 0 ≤ y ≤ 1.0 in Li4-x[SnySi1-y]1-xPxS4). The solid solution is formed by a double substitution that changes the Sn/Si ratio and the M4+ (Sn4+ and Si4+)/P5+ ratio, which adjusts the sizes of the lithium conduction tunnels and the lithium concentration, and contributes to the optimal conductivity value. The highest ionic conductivity value of 1.1 × 10-2 S cm-1 is achieved for the composition of Li10.35[Sn0.27Si1.08]P1.65S12 (Li3.45[Sn0.09Si0.36]P0.55S4) at 298 K, which is close to the value for the original LGPS compound (1.2 × 10-2 S cm-1). The Ge-free solid electrolyte could be suitable for practical applications in all-solid-state batteries. [ABSTRACT FROM AUTHOR]

Carbon replica constructed of three-dimensional, ordered mesopores was employed as the conductive framework for the composite electrode in Li-sulfur all-solid-state batteries. Using a gas-phase mixing method under various conditions, elemental sulfur was introduced into the mesopores with an average diameter of 12 nm. The all-solid-state cells consisted of the sulfur-carbon replica composite cathode, thio-LISICON solid electrolyte, and Li-Al alloy anode. The cells produced discharge capacities of approximately 1500 mAh g-1 in the 1st cycle, which is comparable to the theoretical capacity of sulfur. Thermogravimetric and X-ray diffraction analyses revealed that sulfur deposited inside the mesopores is the main contributor to the excellent performance of the battery. However, sulfur strongly interacted with the carbon replica, reducing the thickness of the carbon wall from 7 to 4 nm. This structural change in the carbon matrix triggered the deterioration of battery performance, especially the cycling capability. Optimizing the sulfur deposition conditions could therefore enhance the performance of batteries using such composite electrodes. [ABSTRACT FROM AUTHOR]

The detailed molecular mechanisms of the pleiotropic effects of statins remain to be fully elucidated. Here, we hypothesized that cardioprotective effects of statins are mediated by small GTP-binding protein GDP dissociation stimulator (SmgGDS). SmgGDS(+/-) and wild-type (WT) mice were treated with continuous infusion of angiotensin II (Ang II) for 2 weeks with and without oral treatment with atorvastatin or pravastatin. At 2 weeks, the extents of Ang II-induced cardiac hypertrophy and fibrosis were comparable between the 2 genotypes. However, statins significantly attenuated cardiomyocyte hypertrophy and fibrosis in WT mice, but not in SmgGDS(+/-) mice. In SmgGDS(+/-) cardiac fibroblasts (CFs), Rac1 expression, extracellular signal-regulated kinases 1/2 activity, Rho-kinase activity, and inflammatory cytokines secretion in response to Ang II were significantly increased when compared with WT CFs. Atorvastatin significantly reduced Rac1 expression and oxidative stress in WT CFs, but not in SmgGDS(+/-) CFs. Furthermore, Bio-plex analysis revealed significant upregulations of inflammatory cytokines/chemokines and growth factors in SmgGDS(+/-) CFs when compared with WT CFs. Importantly, conditioned medium from SmgGDS(+/-) CFs increased B-type natriuretic peptide expression in rat cardiomyocytes to a greater extent than that from WT CFs. Furthermore, atorvastatin significantly increased SmgGDS secretion from mouse CFs. Finally, treatment with recombinant SmgGDS significantly reduced Rac1 expression in SmgGDS(+/-) CFs. These results indicate that both intracellular and extracellular SmgGDS play crucial roles in the inhibitory effects of statins on cardiac hypertrophy and fibrosis, partly through inhibition of Rac1, Rho kinase, and extracellular signal-regulated kinase 1/2 pathways, demonstrating the novel mechanism of the pleiotropic effects of statins. [ABSTRACT FROM AUTHOR]

The effects of surface coatings on LiMn2O4 were investigated using LiMn2O4 epitaxial thin films with a thickness of 30 nm. Bare and surface-coated LiMn2O4 epitaxial thin films were synthesized on SrTiO3 (111) substrates using a pulsed laser deposition method. The surface coating, which was formed using the solid electrolyte Li3PO4 and had a thickness of 3 nm, improved the reversibility of the electrochemical reactions undergone by the LiMn2O4 epitaxial thin films. The modified surface structure provided a stable field for reversible reactions at the electrode surface, resulting in superior battery performance. The changes induced in the surface structure were maintained during battery operation; in contrast, the bare LiMn2O4 thin film exhibited structural degradation and Mn dissolution. The structural changes induced in the coated electrode and the increase in its surface stability were intrinsic effects of the Li3PO4 coating and improved the electrochemical performance of the LiMn2O4 thin-film electrode. [ABSTRACT FROM AUTHOR]

Control over the fractions of layered rock salt and spinel-type phases in Li-(Mn,Co,Ni)-O electrodes was demonstrated using a pulsed laser deposition method. Li-(Mn,Co,Ni)-O epitaxial thin films were deposited on a SrTiO3 (110) substrate and laser energy density (or fluence) was varied to obtain phase fraction control. X-ray diffraction measurements confirmed that the thin films had layered rock salt and spinel-type phases with (1-18) and (110) orientations, respectively. Systematic changes of the phase fraction with fluence variation were clearly confirmed. Relatively low fluence (<900 mJ cm−2) favors the formation of a layered phase while the spinel phase is obtained with higher fluence values (>1000 mJ cm−2). The lithium content in the film determines the fraction of each phase, and higher fluence values lead to lower lithium contents in the spinel phase. These two-phase films show lithium (de)intercalation activities with blended electrode characteristics in their cyclic voltammograms. These films could serve as model electrodes allowing analysis of the reactions of blended Li(Mn,Co,Ni)O2 systems under battery operation conditions. [ABSTRACT FROM AUTHOR]

Epitaxial thin films of the lithium ionic conductor Li0.17La0.61TiO3 have been successfully synthesized on Al2O3(0001) and Nb:SrTiO3(001) substrates at working temperatures below 750°C using pulsed laser deposition. The application of high laser fluence in conjunction with low oxygen pressure was identified as the key to obtaining highly crystalline Li0.17La0.61TiO3 films. The use of low temperatures prevents the loss of lithium during the deposition process and generates films with no compositional deviation from the target, as confirmed by chemical analyses. The Li0.17La0.61TiO3 film deposited on Al2O3(0001) exhibits a high total ionic conductivity of 3.76 × 10-4 S cm-1 at room temperature, which is comparable to the bulk ionic conductivity of polycrystalline Li0.18La0.16TiO3. The low temperature synthetic process described herein should allow the use of new configurations to fabricate electrode-electrolyte interfaces for use in high power all solid-state batteries incorporating Li0.17La0.16TiO3 as the solid electrolyte. [ABSTRACT FROM AUTHOR]

Background: Birth Defects are a series of diseases that seriously affect children's health. Birth defects are generally caused by several interrelated factors. The aims of the article is to estimate the prevalence rate and types of birth defects in Inner Mongolia, China, to compare socio-demographic characteristics among the children with birth defects and to analyze the association between risk factors and birth defects. Methods: Data used in this study were obtained through baseline survey of Inner Mongolia Birth Defects Program, a population-based survey conducted from 2005 to 2008. The survey used cluster sampling method in all 12 administrative districts of Inner Mongolia. Sampling size is calculated according to local population size at a certain percentage. All live births, stillbirths and abortions born from October 2005 to September 2008, whose families lived in Inner Mongolia at least one year, were included. The cases of birth defects were diagnosed by the clinical doctors according to their experiences with further laboratory tests if needed. The inclusion criteria of the cases that had already dead were decided according to death records available at local cites. We calculated prevalence rate and 95% confidence intervals of different groups. Outcome variable was the occurrence of birth defects and associations between risk factors and birth defects were analyzed by using Poisson regression analysis. Results: 976 children with birth defects were diagnosed. The prevalence rate of birth defects was 156.1 per 10000 births (95%CI: 146.3-165.8). The prevalence rate of neural tube defect (20.1 per 10000 births) including anencephaly (6.9 per 10000), spina bifida (10.6 per 10000), and encephalocele (2.7 per 10000) was the highest, followed by congenital heart disease (17.1 per 10000). The relative risk (RR) for maternal age less than 25 was 2.22 (95%CI: 2.05,2.41). The RR of the ethnic Mongols was lower than Han Chinese (RR: 0.84; 95%CI: 0.80-0.89). The RR of the third and second pregnancy was significantly higher than the first pregnancy while a slight difference between the second and the first pregnancy was also found. Alcohol drinking of mothers, familial inheritance and living area were also found to be related to the occurrence of the birth defects.Conclusions: Relatively higher birth defect rates were found in Inner Mongolia. This study found that maternal age less than 25, alcohol drinking, familiar inheritance, lower education level of mothers, times of pregnancies and living in rural areas may increase the risk of birth defects. Ethnic Mongols were less likely to have birth defects than Han Chinese. [ABSTRACT FROM AUTHOR]

Nanoscale analysis of the local lithium-ion concentration in lithium-ion battery cathode materials is essential for achieving high-performance batteries. We developed a near-field optical technique to visualize the lithium-ion distribution in a lithium-ion battery cathode on a nanometer scale. A plasmonic metallic tip was employed to locally enhance and probe the electric field in close proximity to the LiCoO2 thin film, since it is correlated with the lithium-ion concentration at the surface. We also utilized this technique to map the electrochemically induced ion diffusion at the grain boundaries under the application of a DC voltage to the surface through the plasmonic metallic tip. [ABSTRACT FROM AUTHOR]

No design rules have yet been established for producing solid electrolytes with a lithium-ion conductivity high enough to replace liquid electrolytes and expand the performance and battery configuration limits of current lithium ion batteries. Taking advantage of the properties of high-entropy materials, we have designed a highly ion-conductive solid electrolyte by increasing the compositional complexity of a known lithium superionic conductor to eliminate ion migration barriers while maintaining the structural framework for superionic conduction. The synthesized phase with a compositional complexity showed an improved ion conductivity. We showed that the highly conductive solid electrolyte enables charge and discharge of a thick lithium-ion battery cathode at room temperature and thus has potential to change conventional battery configurations. [ABSTRACT FROM AUTHOR]