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In the present study, TiO2-montmorillonite (MMT) composites were synthesized hydrothermally under variable conditions, including the TiO2/MMT mass ratio, reaction pH, reaction temperature, and dwelling time. These samples were determined by X-ray photoelectron spectrometry (XPS), ultraviolet–visible spectroscopy% (UV-Vis DRS), electrochemical impedance spectroscopy (EIS), transient photocurrent responses, photoluminescence (PL) spectra, electron paramagnetic resonance (EPR), and N2 adsorption–desorption isotherms. The photocatalytic activity was evaluated as the ability to promote the visible-light-driven degradation of 30 mg/L of aqueous methylene blue, which was maximized for the composite with a TiO2 mass ratio of 30 wt% prepared at a pH of 6, a reaction temperature of 160 °C, and a dwelling time of 24 h (denoted as 30%-TM), which achieved a methylene blue removal efficiency of 95.6%, which was 4.9 times higher than that of pure TiO2. The unit cell volume and crystallite size of 30%-TM were 92.43 Å3 and 9.28 nm, respectively, with a relatively uniform distribution of TiO2 particles on the MMT's surface. In addition, 30%-TM had a large specific surface area, a strong light absorption capacity, and a high Ti3+ content among the studied catalysts. Thus, the present study provides a basis for the synthesis of composites with controlled structures. [ABSTRACT FROM AUTHOR]

Abstract von Willebrand factor (vWF) is a multimeric glycoprotein essential for hemostasis after vascular injury, which modulates platelet-surface and platelet–platelet interactions by linking platelet receptors to the extracellular matrix and to each other. The crucial role of vWF in platelet function is particularly apparent when hemodynamic conditions create blood flow with high shear stress. Through multiple functional domains, vWF mediates the attachment of platelets to exposed tissues, where immobilized vWF is able to support a homotypic and/or heterotypic self-association. The self-association of vWF is also supported by a rapidly expanding reservoir of novel evidences that the thiol/disulfide exchange regulates vWF multimer size in the blood circulation. Moreover, in addition to proteolysis and reduction of ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13), the regulation of vWF multimer size and self-association may depend on a disulfide bond reductase activity ascribed to thrombospondin-1 (TSP-1). Along with the classical signaling pathways in activated platelets, evidence is emerging that lipid rafts also play important roles in various phases of hemostasis and thrombosis and facilitate the interaction between the key signaling molecules. Developments in these areas will refine our understanding of the role played by vWF self-association in physiological hemostasis and pathological thrombosis.

There has been a dire need for the exploration of renewable clean hydrogen energy recourses in recent years. In this work, we investigated the photocatalytic hydrogen production of heterostructured Ti 3 C 2 /TiO 2 /rGO composites. Ti 3 C 2 /TiO 2 /rGO heterojunction nanocomposites were synthesized using two-step calcination and hydrothermal methods, and the optimum in situ growth ratio of TiO 2 of 71.8% ( n Ti-O / n Ti ) and rGO mass ratio ( m RGO / m TiO 2 /m Ti 3 C 2 ) of 12% were obtained. The target photocatalyst presented an outperforming photocatalytic hydrogen production performance of 1671.85 μmol·g -1 hydrogen production capacity in 4 h, with the maximum hydrogen production rate of 808.11 μmol·g -1 ·h -1 in the first hour being 3.08 times the maximum hydrogen production rate of bare TiO 2 (262.66 μmol·g -1 ·h -1 ). The excellent hydrogen production performance was due to the formed rutile TiO 2 and the constructed heterojunction of Ti 3 C 2 /TiO 2 /rGO, where rGO provided different electron transport channels, and made charge transfer easier, and restrained the recombination efficiency of electrons and holes.