Two-dimensional vanadium carbide (V 2 C) and titanium carbide (Ti 3 C 2 ) MXenes were first synthesized by exfoliating V 2 AlC or Ti 3 AlC 2 and then introduced jointly into magnesium hydride (MgH 2 ) to tailor the hydrogen desorption/absorption performances of MgH 2 . The as-prepared MgH 2 −V 2 C−Ti 3 C 2 composites show much better hydrogen storage performances than pure MgH 2 . MgH 2 with addition of 10 wt % of 2V 2 C/Ti 3 C 2 initiates hydrogen desorption at around 180 °C; 5.1 wt % of hydrogen was desorbed within 60 min at 225 °C, while 5.8 wt % was desorbed within 2 min at 300 °C. Under 6 MPa H 2 , the dehydrided MgH 2 −2V 2 C/Ti 3 C 2 can start to recover hydrogen at room temperature, and 5.1 wt % of H 2 is obtained within 20 s at a constant temperature of 40 °C. The reversible capacity (6.3 wt %) does not decline for up to 10 cycles, which shows excellent cycling stability. The addition of 2V 2 C/Ti 3 C 2 can remarkably lower the activation energy for the hydrogen desorption reaction of MgH 2 by 37% and slightly reduce the hydrogen desorption reaction enthalpy by 2 kJ mol −1 H 2 . It was demonstrated that the combination of V 2 C and Ti 3 C 2 promotes the hydrogen-releasing process of MgH 2 compared with addition of only V 2 C or Ti 3 C 2 , while Ti 3 C 2 impacts MgH 2 more significantly than V 2 C in the hydrogen absorption process of MgH 2 at ambient temperatures. A possible mechanism in the hydrogen release and uptake of the MgH 2 −V 2 C−Ti 3 C 2 system was proposed as follows: hydrogen atoms or molecules may preferentially transfer through the MgH 2 /V 2 C/Ti 3 C 2 triple-grain boundaries during the desorption process and through the Mg/ Ti 3 C 2 interfaces during the absorption process. Microstructure studies indicated that V 2 C and Ti 3 C 2 mainly act as efficient catalysts for MgH 2 . This work provides an insight into the hydrogen storage behaviors and mechanisms of MgH 2 boosted by a combination of two MXenes.

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Serine-arginine (SR) proteins are essential splicing factors containing a canonical RNA recognition motif (RRM), sometimes followed by a pseudo-RRM, and a C-terminal arginine/ serine-rich (RS) domain that undergoes multisite phosphorylation. Phosphorylation regulates the localization and activity of SR proteins, and thus may provide insight into their differential biological roles. The phosphorylation mechanism of the prototypic SRSF1 by serine-arginine protein kinase 1 (SRPK1) has been well-studied, but little is known about the phosphorylation of other SR protein members. In the present study, interaction and kinetic assays unveiled how SRSF1 and the single RRMcontaining SRSF3 are phosphorylated by SRPK2, another member of the SRPK family. We showed that a conserved SRPKspecific substrate-docking groove in SRPK2 impacts the binding and phosphorylation of both SR proteins, and the localization of SRSF3. We identified a nonconserved residue within the groove that affects the kinase processivity. We demonstrated that, in contrast to SRSF1, for which SRPK-mediated phosphorylation is confined to the N-terminal region of the RS domain, SRSF3 phosphorylation sites are spread throughout its entire RS domain in vitro. Despite this, SRSF3 appears to be hypophosphorylated in cells at steady state. Our results suggest that the absence of a pseudo-RRM renders the single RRM-containing SRSF3 more susceptible to dephosphorylation by phosphatase. These findings suggest that the single RRM-and two RRMcontaining SR proteins represent two subclasses of phosphoproteins in which phosphorylation statuses are maintained by unique mechanisms, and pose new directions to explore the distinct roles of SR proteins in vivo.

A RuO2/Co3O4heterojunction catalyst with a perfect OER and HER overpotential in 1 M KOH solution was synthesized. It contains only a small amount of precious metal oxides but demonstrates a better performance than most reported Co3O4-based electrocatalysts.

Simple fused-ring nonfullerene acceptor BDDEH with benzobithiophenedione as core unit is obtained through organostannane-free and ligand-free direct heteroarylation approach for the first time, which delivers a high efficiency of 12.59% in PSCs.

Polyglutamine (polyQ) diseases are a class of progressive neurodegenerative disorders characterized by the expression of both expanded RNA and misfolded polyQ protein. We previously reported that the direct interaction between expanded RNA and nucleolar protein nucleolin (NCL) impedes RNA () transcription, and eventually triggers nucleolar stress-induced apoptosis in polyQ diseases. Here, we report that a 21-amino acid peptide, named "beta-structured inhibitor for neurodegenerative diseases" (BIND), effectively suppresses toxicity induced by expanded RNA. When administered to a cell model, BIND potently inhibited cell death induced by expanded RNA with an IC value of ∼0.7 µM. We showed that the function of BIND is dependent on Glu2, Lys13, Gly14, Ile18, Glu19, and Phe20. BIND treatment restored the subcellular localization of nucleolar marker protein and the expression level of Through isothermal titration calorimetry analysis, we demonstrated that BIND suppresses nucleolar stress via a direct interaction with RNA in a length-dependent manner. The mean binding constants () of BIND to , , , and RNA are 17.28, 5.60, 4.83, and 0.66 µM, respectively. In vivo, BIND ameliorates retinal degeneration and climbing defects, and extends the lifespan of expressing expanded RNA. These effects suggested that BIND can suppress neurodegeneration in diverse polyQ disease models in vivo and in vitro without exerting observable cytotoxic effect. Our results collectively demonstrated that BIND is an effective inhibitor of expanded RNA-induced toxicity in polyQ diseases.

Cell growth and differentiation are controlled in many tissues by paracrine factors, which often require proteolytic processing for activation. Metalloproteases of the metzincin family, such as matrix metalloproteases and ADAMs, recently have been shown to be involved in the shedding of growth factors, cytokines, and receptors. In the present study, we show that hydroxamate-based inhibitors of metalloproteases (HIMPs), such as TAPI and BB-3103, increase the fusion of C(2)C(12) myoblasts and provoke myotube hypertrophy. HIMPs did not seem to effect hypertrophy via proteins that have previously been shown to regulate muscle growth in vitro, such as insulin-like growth factor-I, calcineurin, and tumor necrosis factor-alpha. Instead, the proteolytic maturation of myostatin (growth differentiation factor-8) seemed to be reduced in C(2)C(12) cells treated with HIMPs, as suggested by the presence of nonprocessed myostatin precursor only in hypertrophic myotubes. Myostatin is a known negative regulator of skeletal muscle growth, belonging to the transforming growth factor-beta/bone morphogenetic protein superfamily. These results indicate that metalloproteases are involved in the regulation of skeletal muscle growth and differentiation, that the proteolytic maturation of myostatin in C(2)C(12) cells may be directly or indirectly linked to the activity of some unidentified HIMP-sensitive metalloproteases, and that the lack of myostatin processing on HIMP treatment may be a mediator of myotube hypertrophy in this in vitro model.

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