Concentration-gradient LiMn0.8Fe0.2PO4 cathode material for high performance lithium ion battery

It is a great challenge to combine good cycling performance with high rate capability for LiMn1-xMxPO4 cathode materials owing to the Mn dissolution upon cycling and its low electronic/ionic conductivity. Here, we report a novel concentration-gradient structure of LiMn0.8Fe0.2PO4 material constructed by solvothermal treatment. This material shows a linear increase of Mn concentration from the edge to the particle centre, but the inverse trend for Fe concentration, which leads to the formation of Mn-rich phase in bulk and Fe-rich phase at surface. The Fe-rich phase effectively suppresses the corrosion from the electrolyte that minimizes the Mn dissolution and also improves the electronic/ionic conductivity of the surface that decreases the cathode/electrolyte interface resistance. Consequently, this concentration-gradient material achieves superior capacity retention with 98% after 50 cycles at 1 degrees C even at elevated temperature, and also exhibits an excellent rate capability with the reversible capacity of 130 mA h g(-1) at 5 degrees C rate. These results suggest that the concentration-gradient LiMn0.8Fe0.2PO4 is an ideal type of cathode material for high performance Lithium ion batteries. (C) 2015 Elsevier B.V. All rights reserved

Hsp70/Bmi1-FoxO1-SOD Signaling Pathway Contributes to the Protective Effect of Sound Conditioning against Acute Acoustic Trauma in a Rat Model

Sound conditioning (SC) is defined as “toughening” to lower levels of sound over time, which reduces a subsequent noise-induced threshold shift. Although the protective effect of SC in mammals is generally understood, the exact mechanisms involved have not yet been elucidated. To confirm the protective effect of SC against noise exposure (NE) and the stress-related signaling pathway of its rescue, we observed target molecule changes caused by SC of low frequency prior to NE as well as histology analysis in vivo and verified the suggested mechanisms in SGNs in vitro. Further, we investigated the potential role of Hsp70 and Bmi1 in SC by targeting SOD1 and SOD2 which are regulated by the FoxO1 signaling pathway based on mitochondrial function and reactive oxygen species (ROS) levels. Finally, we sought to identify the possible molecular mechanisms associated with the beneficial effects of SC against noise-induced trauma. Data from the rat model were evaluated by western blot, immunofluorescence, and RT-PCR. The results revealed that SC upregulated Hsp70, Bmi1, FoxO1, SOD1, and SOD2 expression in spiral ganglion neurons (SGNs). Moreover, the auditory brainstem responses (ABRs) and electron microscopy revealed that SC could protect against acute acoustic trauma (AAT) based on a significant reduction of hearing impairment and visible reduction in outer hair cell loss as well as ultrastructural changes in OHCs and SGNs. Collectively, these results suggested that the contribution of Bmi1 toward decreased sensitivity to noise-induced trauma following SC was triggered by Hsp70 induction and associated with enhancement of the antioxidant system and decreased mitochondrial superoxide accumulation. This contribution of Bmi1 was achieved by direct targeting of SOD1 and SOD2, which was regulated by FoxO1. Therefore, the Hsp70/Bmi1-FoxO1-SOD signaling pathway might contribute to the protective effect of SC against AAT in a rat model

The structure, morphology, and electrochemical properties of Li1+xNi1/6Co1/6Mn4/6O2.25+x/2 (0.1 ≤ x ≤ 0.7) cathode materials

Li1+xNi1/6Co1/6Mn4/6O2.25+x/2 (0.1≤x≤0.7) cathode materials have been synthesized by a simple carbonate co-precipitation method. The effects of the lithium content on the structure, physical property, and electrochemical performance of the samples have been investigated. As the increase of lithium content, the Li1+xNi1/6Co1/6Mn4/6O2.25+x/2 evolves from a mixture of hexagonal R？3m, monoclinic C2/m, and spinel Fd？3m structure to a mixture of hexagonal and monoclinic structure, accompanied with less cation mixing between Li+ and Ni2+. The increase of x value also affects the size of the primary particles and the roughness of the secondary particles. The i1+xNi1/6Co1/6Mn4/6O2.25+x/2 with appropriate lithium content, e.g., x = 0.3, thereby small particle size, high pellet density, and low cation mixing, brings on the largest discharge capacity, which is more than 288 mAh g？1 in the voltage range of 2.0–4.8 V at 25 mA g？1, and the lowest irreversible capacity loss of 47 mAh g？1 among these cathode materials

Comparative genomic analyses reveal the genetic basis of the yellow-seed trait in Brassica napus

Abstract Yellow-seed trait is a desirable breeding characteristic of rapeseed (Brassica napus) that could greatly improve seed oil yield and quality. However, the underlying mechanisms controlling this phenotype in B. napus plants are difficult to discern because of their complexity. Here, we assemble high-quality genomes of yellow-seeded (GH06) and black-seeded (ZY821). Combining in-depth fine mapping of a quantitative trait locus (QTL) for seed color with other omics data reveal BnA09MYB47a, encoding an R2R3-MYB-type transcription factor, as the causal gene of a major QTL controlling the yellow-seed trait. Functional studies show that sequence variation of BnA09MYB47a underlies the functional divergence between the yellow- and black-seeded B. napus. The black-seed allele BnA09MYB47aZY821, but not the yellow-seed allele BnA09MYB47aGH06, promotes flavonoid biosynthesis by directly activating the expression of BnTT18. Our discovery suggests a possible approach to breeding B. napus for improved commercial value and facilitates flavonoid biosynthesis studies in Brassica crops