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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]

Summary: In this meta‐analysis, we aim to evaluate the risk of gallbladder and biliary disease of weight management strategies and investigate the association between weight reduction and risk of gallbladder or biliary disease. Randomized controlled trials (RCTs) with a duration of at least 12 weeks that compare antiobesity medications (AOMs) with placebo or bariatric surgery with less intensive weight management strategy were concluded. Weight management strategy was associated with a significant increased risk of gallbladder or biliary disease (OR 1.361, 95% CI 1.147 to 1.614, P < 0.001, I2 = 3.5%), cholelithiasis, cholecystitis, and cholecystectomy compared with placebo or controls. The increased risk of gallbladder or biliary disease was observed both in pharmacotherapies subgroup and bariatric surgery subgroup. With regards of specific pharmacotherapies, an increased risk of gallbladder or biliary disease was observed in trials with glucagon‐like peptide 1 receptor agonist (GLP‐1 RA) treatments. In addition, trials with indication of obesity and overweight treatment and trials with higher doses showed significant higher risk of gallbladder or biliary disease compared with placebo or controls. In conclusion, weight management strategy was associated with an increased risk of gallbladder or biliary disease when compared with placebo or control groups. [ABSTRACT FROM AUTHOR]

The fabrication of MnBi2Te4 family of materials has been demonstrated that intercalating magnetic MnTe layer into topological insulator Bi2Te3 is an efficient way to explore magnetic topological insulator. A natural question is that if multiple MnTe layers can be intercalated into Bi2Te3, meanwhile if the topological properties are well preserved. Based on first-principles calculations, we first confirm that multiple MnTe layers can be inserted into Bi2Te3 by forming antiferromagnetic MnnBi2Te3+n (n = 1–5) crystals, where each system is energetically stable and can be readily exfoliated down to a monolayer. Specifically, the structural phase transition from ABC to ABAC stacking happens when n ≥ 2. Further electronic band structure calculations and topological identification reveal that the magnetic MnnBi2Te3+n undergoes a topologically nontrivial to trivial phase transition when n > 2, which is attributed to that multiple MnTe layers destroy the topological property of Bi2Te3. In addition to applying compressed strain, the topological states can be restored by intercalating Bi2Te3 layers by forming (MnTe)n(Bi2Te3)m heterostructures. Most strikingly, it is found that the topological properties of (MnTe)n(Bi2Te3)m are universally determined by the ratio of n/m, once n/m ≤ 2.8, the desired topological states are recovered. Our notable findings enrich the family of magnetic topological insulator, providing opportunities to explore more intriguing topological phenomena. [ABSTRACT FROM AUTHOR]

The fabrication of MnBi2Te4 family of materials has been demonstrated that intercalating magnetic MnTe layer into topological insulator Bi2Te3 is an efficient way to explore magnetic topological insulator. A natural question is that if multiple MnTe layers can be intercalated into Bi2Te3, meanwhile if the topological properties are well preserved. Based on first-principles calculations, we first confirm that multiple MnTe layers can be inserted into Bi2Te3 by forming antiferromagnetic MnnBi2Te3+n (n = 1–5) crystals, where each system is energetically stable and can be readily exfoliated down to a monolayer. Specifically, the structural phase transition from ABC to ABAC stacking happens when n ≥ 2. Further electronic band structure calculations and topological identification reveal that the magnetic MnnBi2Te3+n undergoes a topologically nontrivial to trivial phase transition when n > 2, which is attributed to that multiple MnTe layers destroy the topological property of Bi2Te3. In addition to applying compressed strain, the topological states can be restored by intercalating Bi2Te3 layers by forming (MnTe)n(Bi2Te3)m heterostructures. Most strikingly, it is found that the topological properties of (MnTe)n(Bi2Te3)m are universally determined by the ratio of n/m, once n/m ≤ 2.8, the desired topological states are recovered. Our notable findings enrich the family of magnetic topological insulator, providing opportunities to explore more intriguing topological phenomena. [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]

Similar to the magnetic topological insulator of MnBi2Te4, recent studies have demonstrated that VBi2Te4 is also an ideal candidate to explore many intriguing quantum states. Different from the strong interlayer antiferromagnetic (AFM) coupling in layered MnBi2Te4, based on first-principles calculations, we find that the energy difference between AFM and ferromagnetic (FM) orders in layered VBi2Te4 is much smaller than that of MnBi2Te4. Specifically, it is found that the interlayer FM coupling can be readily achieved by applying strain. Further electronic band structures reveal that the VBi2Te4 bilayer is a time-reversal symmetry broken quantum spin Hall insulator with a spin Chern number of CS = 1, which is essentially different from the QAH state with a Chern number of C = 1 in the MnBi2Te4 bilayer. Most strikingly, the topological states of the magnetic VBi2Te4 bilayer can be well tuned by strain, whose topological phase diagram is mapped out as a function of strain by employing continuum model analyses. All of these results indicate that the layered VBi2Te4 not only enriches the family of magnetic topological materials, but also provides a promising platform to explore more exotic quantum phenomena. [ABSTRACT FROM AUTHOR]

In this work, we use first-principles calculations to determine the interplay between spin–orbit coupling (SOC) and magnetism which can not only generate a quantum anomalous Hall state but can also result in topologically trivial states although some honeycomb systems host large band gaps. By employing tight-binding model analysis, we have summarized two types of topologically trivial states: one is due to the coexistence of quadratic non-Dirac and linear Dirac bands in the same spin channel that act together destructively in magnetic materials (such as, CrBr3, CrCl3, and VBr3 monolayers); the other one is caused by the destructive coupling effect between two different spin channels due to small magnetic spin splitting in heavy-metal-based materials, such as, BaTe(111)-supported plumbene. Further investigations reveal that topologically nontrivial states can be realized by removing the Dirac band dispersion of the magnetic monolayers for the former case (such as in alkali metal doped CrBr3), while separating the two different spin channels from each other by enhancing the magnetic spin splitting for the latter case (such as in half-iodinated silicene). Thus, our work provides a theoretical guideline to manipulate the topological states in a two-dimensional honeycomb lattice. [ABSTRACT FROM AUTHOR]

Understanding particle flow characteristics can help improve the efficiency of nonmetallic ore powder air classifiers. In this paper, dissipative particle dynamics (DPD) and the discrete element method (DEM) were adopted to study the interactions between the gas phase and solid particles. Gas and solid phases were coupled using the single-particle DPD model. Taking sepiolite particles as an example, at the optimal input air velocity in the pipeline, the gas particle velocity distribution, solid particle velocity distribution, solid particle concentration distribution, and solid particle position distribution were analyzed by numerical simulations. A comparison of numerical simulation and experimental results showed that when the input air velocity U a in the pipeline was 17 m/s, the velocity of particles and gas in the pipeline gradually increased from the wall to the center of the pipeline. The velocity near the pipeline wall changed rapidly, and the velocity in the main flow area remained basically unchanged. Particles left the pipeline in a uniform and dispersed state and were carried into the classification area. As the input air velocity increased, the pressure drop across the pipeline also increased. Therefore, the optimal input air velocity value could be reasonably selected to minimize energy consumption. [ABSTRACT FROM AUTHOR]

Glucokinase variant-induced maturity-onset diabetes of the young (GCK-MODY) exhibits the unique clinical features of mild fasting hyperglycemia. However, formal studies of its glucose excursion pattern in daily life in comparison with those with or without other types of diabetes are lacking. We conducted a case-control study including 25 patients with GCK-MODY, 25 A1C-matched, drug-naive patients with type 2 diabetes (T2DM), and 25 age-, BMI-, and sex-matched subjects with normal glucose tolerance (NGT). All the subjects wore flash glucose monitoring (FGM) sensors for 2 weeks, and glucose readings were masked. Glucose excursion was significantly lower in the GCK-MODY than that in A1C-matched T2DM during the daytime, but was similar during the nighttime. The daytime coefficient of variation (CV) driven by postprandial glucose could separate GCK-MODY from well-controlled T2DM, but the nighttime CV could not. In discriminating between GCK-MODY and T2DM, the area under the curve of the CV was 0.875. However, in GCK-MODY and NGT subjects, the CVs were similar at 24 h, whereas the other four excursion parameters were significantly higher in GCK-MODY than those in NGT subjects. FGM confirmed the stability and mildness of hyperglycemia in GCK-MODY patients. Postprandial regulation is a key driver of the difference in excursion between GCK-MODY and T2DM. [ABSTRACT FROM AUTHOR]