Design and Performance of Rechargeable Sodium Ion Batteries,and Symmetrical Li‐Ion Batteries with Supercapacitor‐Like Power Density Based upon Polyoxovanadates

The polyanion Li₇V₁₅O₃₆(CO₃) is a nanosized molecular cluster (≈1 nm in size), that has the potential to form an open host framework with a higher surface‐to‐bulk ratio than conventional transition metal oxide electrode materials. Herein, practical rechargeable Na‐ion batteries and symmetric Li‐ion batteries are demonstrated based on the polyoxovanadate Li₇V₁₅O₃₆(CO₃). The vanadium centers in {V₁₅O₃₆(CO₃)} do not all have the same V^IV/V redox potentials, which permits symmetric devices to be created from this material that exhibit battery‐like energy density and supercapacitor‐like power density. An ultrahigh specific power of 51.5 kW kg^?1 at 100 A g^?1 and a specific energy of 125 W h kg^?1 can be achieved, along with a long cycling life (>500 cycles). Moreover, electrochemical and theoretical studies reveal that {V₁₅O₃₆(CO₃)} also allows the transport of large cations, like Na⁺, and that it can serve as the cathode material for rechargeable Na‐ion batteries with a high specific capacity of 240 mA h g^?1 and a specific energy of 390 W h kg^?1 for the full Na‐ion battery. Finally, the polyoxometalate material from these electrochemical energy storage devices can be easily extracted from spent electrodes by simple treatment with water, providing a potential route to recycling of the redox active material.     

Data‐independent acquisition‐based SWATH‐MS for quantitative proteomics: a tutorial

Many research questions in fields such as personalized medicine, drug screens or systems biology depend on obtaining consistent and quantitatively accurate proteomics data from many samples. SWATH‐MS is a specific variant of data‐independent acquisition (DIA) methods and is emerging as a technology that combines deep proteome coverage capabilities with quantitative consistency and accuracy. In a SWATH‐MS measurement, all ionized peptides of a given sample that fall within a specified mass range are fragmented in a systematic and unbiased fashion using rather large precursor isolation windows. To analyse SWATH‐MS data, a strategy based on peptide‐centric scoring has been established, which typically requires prior knowledge about the chromatographic and mass spectrometric behaviour of peptides of interest in the form of spectral libraries and peptide query parameters. This tutorial provides guidelines on how to set up and plan a SWATH‐MS experiment, how to perform the mass spectrometric measurement and how to analyse SWATH‐MS data using peptide‐centric scoring. Furthermore, concepts on how to improve SWATH‐MS data acquisition, potential trade‐offs of parameter settings and alternative data analysis strategies are discussed.     

Tim‐2 is the receptor for H‐ferritin on oligodendrocytes

Oligodendrocytes stain more strongly for iron than any other cell in the CNS, and they require iron for the production of myelin. For most cell types transferrin is the major iron delivery protein, yet neither transferrin receptor protein nor mRNA are detectable in mature oligodendrocytes. Thus an alternative iron delivery mechanism must exist. Given the significant long term consequences of developmental iron deficiency and the iron requirements for normal myelination, identification of the iron delivery mechanism for oligodendrocytes is important. Previously we have reported that oligodendrocytes bind H‐ferritin and that H‐ferritin binds to white matter tracts in vivo. Recently, T cell immunoglobulin and mucin domain‐containing protein‐2 (Tim‐2) was shown to bind and internalize H‐ferritin. In the present study we show that Tim‐2 is expressed on oligodendrocytes both in vivo and in vitro. Further, the onset of saturable H‐ferritin binding in CG4 oligodendrocyte cell line is accompanied by Tim‐2 expression. Application of a blocking antibody to the extracellular domain of Tim‐2 significantly reduces H‐ferritin binding to the differentiated CG4 cells and primary oligodendrocytes. Tim‐2 expression on CG4 cells is responsive to iron; decreasing with iron loading and increasing with iron chelation. Taken together, these data provide compelling evidence that Tim‐2 is the H‐ferritin receptor on oligodendrocytes suggesting it is the primary mechanism for iron acquisition by these cells.