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As a common method for preparing micron powder in industrial operations, the mechanical extrusion method simply pursues the particle size without considering the microstructure characteristics of sepiolite, which leads to problems such as bundles of sepiolite not being effectively dispersed, and thus the disruption of fibers is inevitably caused. In this work, a new micronization method for disaggregating these bundles while preserving the original structural integrity of the fibers is proposed based on steam pressure changes. The effects of steam pressure changes on the particle size distribution, microstructure, and properties of treated sepiolite are studied using X-ray fluorescence spectrometer (XRF), X-ray diffractometer (XRD), Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), and a specific surface area and aperture analyzer (BET). The experimental results show that the particle size of sepiolite powder depends greatly on steam pressure, and sepiolite powder with mass ratio of 91.6% and a particle size D97 of 21.27 μm is obtained at a steam pressure of 0.6 MPa. Compared to the sepiolite after mechanical extrusion, the sepiolite treated with steam pressure changes can maintain the integrity of its crystalline structure. The specific surface area of sepiolite enhanced from 80.15 m2 g−1 to 141.63 m2 g−1 as the steam pressure increased from 0.1 to 0.6 MPa, which is about 1.6 times that of the sample treated with mechanical extrusion. [ABSTRACT FROM AUTHOR]

Aims: Whether sodium‐glucose co‐transporter 2 inhibitors are effective for heart failure caused by ATTR‐CA (transthyretin cardiac amyloidosis) remains uncertain. The aim of this study is to investigate the cardiovascular prognosis in ATTR‐CA mice model with dapagliflozin treatment. Methods and results: Humanized RBP4/TTRVal50Met and RBP4/TTR mice models were constructed with clustered regularly interspaced short palindromic repeats and associated Cas9 endonuclease (CRISPR‐Cas9) techniques and multiple generations breeding. A total of 6 RBP4/TTR mice received placebo treatment, when 12 RBP4/TTRVal50Met received dapagliflozin (1 mg/kg/day, 6 mice) and placebo (6 mice) treatment. Fasting glucose, intraperitoneal glucose tolerance test, and plasma brain natriuretic peptide (BNP) concentration were measured at Day 0, Week 2, and Week 4. BNP, transforming growth factor‐beta (TGF‐β), collagen type I alpha 1 (COL1A1) protein levels, and Cola1, TGFβ1, TNFα, IL‐1β, BNP relative quantities in cardiac, along with cardiac pathology examination including right ventricular collagen percentage, ventricular septum thickness, left ventricular wall thickness, and left ventricular internal diameter were measured at Week 4 after treatment procedure. All 18 mice completed the experiment. The baseline characteristics were balanced among three treatment groups. In placebo‐treated mice, the cardiac BNP relative quantity was significantly higher in RBP4/TTRVal50Met mice than RBP4/TTR mice (RBP4[KI/KI], TTR [KI/KI]: 0.72 ± 0.46, RBP4[KI/KI], TTRVal50Met[KI/KI]: 1.44 ± 0.60, P = 0.043), indicating more significant heart failure progression in ATTR‐CA mice than normal mice. In ATTR‐CA mice, the cardiovascular prognosis measurements including heart failure (plasma BNP concentration and relative quantities of BNP), cardiac inflammation (relative quantities of Cola1, TGFβ1, TNFα, and IL‐1β), and pathological changes (right ventricular collagen percentage, ventricular septum thickness, left ventricular wall thickness, and left ventricular internal diameter) were statistically comparable between those under dapagliflozin and placebo treatment. Conclusions: Dapagliflozin did not improve cardiovascular prognosis including the progression of heart failure, cardiac inflammation, and pathological changes in ATTR‐CA mice compared with placebo. The results of this study were not in support of dapagliflozin's therapeutic effects for ATTR‐CA. More pre‐clinical and clinical researches to validate these findings and demonstrate the underlying mechanisms are still required. [ABSTRACT FROM AUTHOR]

Photoinduced reactive oxygen species (ROS)‐based pollutant removal is one of the ideal solutions to achieve the conversion of solar energy into chemical energy and thus to address environmental pollution. Here, earth‐abundant CaCO3‐decorated g‐C3N4 (g‐C3N4 labeled as CN, CaCO3‐decorated g‐C3N4 sample labeled as CN‐CCO) has been constructed by a facile thermal polymerization method for safe and efficient photocatalytic NO removal. The decorated CaCO3 as "transit hub" extends the π bonds of CN to deviate from the planes and steers the random charge carriers, which thus provides extra active sites and expedites spatial charge separation to facilitate adsorption/activation of reactants and promote formation of ROS participating in the removal of pollutant. Furthermore, boosted generation of ROS regulates the photocatalytic NO oxidation pathway and thus increases the selectivity of products. NO prefers to be directly oxidized into final product (nitrate) rather than toxic intermediates (NO2), which is well demonstrated by theoretically simulated ROS‐based reaction pathways and experimental characterization. The present work promotes the degradation of pollutant and simultaneously suppresses the formation of toxic by‐product, which paves the way for ROS‐based pollutant removal. [ABSTRACT FROM AUTHOR]