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Isocyanate‐based monomers and polymers have found widespread industrial application; however, the realization of green water‐based products via the preparation of stable isocyanate aqueous emulsions remains challenging. Herein, a series of organosilicon and organofluorine synergistically modified amphiphilic branched polyurethanes (HBWPU), synthesized by grafting perfluorohexyl ethanol semi‐terminated isophorone diisocyanate (IPDI) onto a hydrophilic polyurethane prepolymer, is presented. Subsequently, using a physical mixing method, stable diisocyanate emulsions are fabricated by preparing diisocyanate latex particles with IPDI as the core and hyperbranched water‐based polyurethanes (HBWPU) as the shell. Structural investigations showed that the branching degree and fluorine content of the HBWPU significantly affects the stability of the diisocyanate emulsions. Increasing the degree of branching from 0.34 to 0.86 causes the amount of residual isocyanate (NCO) groups to decrease from 20.1% to 16.7%. In contrast, an increase in the fluorine content from 0% to 17.8% increases the amount of residual NCO groups from 11.5% to 24.6%. Thus, HBWPU can be used as an emulsifier to prepare waterborne diisocyanate cross‐linking agents. Such polyurethane‐coated isocyanate aqueous emulsions can increase the hardness and significantly improve the acetone resistance of hydroxyl polyacrylate resins. [ABSTRACT FROM AUTHOR]

The three‐point bending test was conducted and the digital image correlation (DIC) technique was used to observe the full‐field displacement and strain of the notched beam. The initial cracking load and the crack mouth opening displacement were determined based on the deformation field near the tip and mouth of the notch. The initial cracking toughness Kini and the unstable fracture toughness Kun calculated according to the double‐K fracture model, the fracture energy GF and the ductility index Du determined with a modified method, and the equivalent fracture toughness K at four different deformation stages, were analyzed under different temperatures and basalt fiber contents. The results showed that Kini exhibited a monotonic decrease trend with the increasing temperature, indicating that the notched beam was prone to initial cracking after high temperatures. However, Kini rose slowly with the increase of the fiber content, suggesting that the basalt fiber had little influence on Kini. At the temperatures below 400°C, the Kun, GF, Du, and K at each deformation stage increased with the rise of temperature. At the temperatures above 400°C, the Kun, GF, Du, and K at each deformation stage apparently decreased with the increase of temperature. Under the current test conditions, the basalt fiber content of 0.4% by volume had the greatest improvement on the fracture performances of concrete after high temperatures. [ABSTRACT FROM AUTHOR]

Digital Image Correlation (DIC) technique is used to collect the whole‐field strain of concrete subjected to bending loads under different temperature change cycles, cooling rates, and water‐binder ratio. The bending damage behavior of concrete under large‐difference temperature circulation is analyzed with the whole‐field strain cloud map and data. In addition, with the whole‐field strain obtained by 3D‐DIC technology, the strain‐based damage variable is defined. Furthermore, the damage degree of concrete specimen in the bending process is quantified, and the bending damage evolution process of concrete under the action of temperature circulation is discussed. The results show that the damage of concrete in areas with large temperature differences is related to the number of temperature change cycles as well as the cooling rate. Moreover, the increase in the number of temperature change cycles and the cooling rate will aggravate the bending damage of the concrete. Additionally, the higher the water‐binder ratio, the more serious the adverse effect of temperature circulation on the concrete. This paper provide certain reference for the evaluation of concrete bending deformation damage in areas with a large temperature difference. [ABSTRACT FROM AUTHOR]

To study the effect of pore structure changes on the fatigue life of concrete in areas with large temperature differences, a concrete fatigue test program was designed after a temperature cycle of −50 to 70°C. Results show that temperature differences considerably influence pores with a size ranging from 0.1 to 27.98 nm. Furthermore, the fatigue life of concrete gradually decreases with the increase in the pore structure parameters of 0.1 to 27.98 nm. This result indicates that the effect of temperature difference on the fatigue life of concrete in areas with large temperature differences must not be ignored. The combined effect of temperature differences and load increases the coarsening rate of the pore structure, and the load remarkably affects pores with a size ranging from 524.26 to 10,000 nm. To characterize the pore structure of concrete under temperature cycling and fatigue load, two pore structure characteristic parameters, namely, comprehensive change rate of pore size (Sz) and pore structure complexity coefficient (Cz), are proposed. These parameters, together with the total porosity (Ptotal), form a three‐dimensional pore structure characteristic parameter and establish the relationship expression between the three‐dimensional pore structure parameters and the fatigue life of concrete (N); thus, they provide basis for the prediction of the fatigue life of concrete on the basis of pore structure. [ABSTRACT FROM AUTHOR]

The roof collapse of deep cavities has been investigated only under fully dry or saturated conditions. However, natural soils are largely unsaturated, and consequently, their mechanical behavior is significantly different owing to the presence of matric suction. In this study, a novel analytical solution for the roof collapse of deep cavities in unsaturated soils is developed based on the upper bound theorem and the nonlinear Mohr–Coulomb criterion, and the width of a cavity with an arbitrary shape at collapse is derived. Subsequently, a parametric study is conducted to investigate the effects of water retention properties, effective cohesion, friction angle, supporting pressure, and nonlinear coefficient on the safety factors of rectangular deep cavities. It is found that matric suction and soil type have significant influences on the stability of deep cavities. There is a peak for the safety factors of deep cavities as the matric suction increases when the water‐holding capacity of the soil is low. This novel analytical solution provides a new insight into the stability of deep cavities in unsaturated soils. [ABSTRACT FROM AUTHOR]

Cyclosporin A (CsA) is a well‐known and effective drug that is commonly used in autoimmune diseases and allotransplantation. However, kidney toxicity and cardiotoxicity limit its use. Circular RNAs (circRNAs) play a crucial role in disease, especially cardiovascular disease. We aimed to explore the circRNA expression profiles and potential mechanisms during CsA‐induced cardiotoxicity. Sixty male adult Wistar rats were randomly divided into two groups. The CsA group was injected with CsA (15 mg/kg/day body weight) intraperitoneally (ip) for 2 weeks, whereas the control group was injected ip with the same volume of olive oil. We assessed CsA‐induced cardiotoxicity by light microscopy, transferase‐mediated dUTP nick‐end labeling (TUNEL) staining, and electron microscopy. Microarray analysis was used to detect the expression profiles of circRNAs deregulated in the heart during CsA‐induced cardiotoxicity. We confirmed the changes in circRNAs by quantitative PCR. Moreover, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses of the microarray data were performed. A conventional dose of CsA induced cardiotoxicity in rats. We identified 67 upregulated and 37 downregulated circRNAs compared with those in the control group. Six of 12 circRNAs were successfully verified by quantitative real‐time polymerase chain reaction (qRT‐PCR). GO analyses of the differentially expressed circRNAs indicated that these molecules might play important roles in CsA‐induced cardiotoxicity. KEGG pathway analyses showed that the differentially expressed circRNAs in CsA‐induced cardiotoxicity may be related to autophagy or the Hippo signaling pathway. We identified differential circRNA expression patterns and provided more insight into the mechanism of CsA‐induced cardiotoxicity. CircRNAs may serve as potential biomarkers or therapeutic targets of CsA‐mediated cardiotoxicity in the future. Multiple circRNAs were deregulated during CsA‐induced cardiotoxicity. A conventional dose of CsA could induce cardiomyocyte toxicity in rats. Differentially expressed circRNAs were related to autophagy or the Hippo signaling pathway in CsA‐induced cardiotoxicity. Our study could help elucidate the molecular mechanisms of CsA‐mediated cardiotoxicity. CircRNAs may serve as potential biomarkers or therapeutic targets of CsA‐mediated cardiotoxicity in the future. [ABSTRACT FROM AUTHOR]

The soil water characteristic curve (SWCC) is an important tool in soil science and geotechnical applications. Most previous studies on SWCCs are limited to one to three drying‐wetting cycles, mainly because SWCC measurement is complex and time‐consuming. The numerous models that have been proposed to predict hysteresis in SWCCs. In this paper, a novel simplified equation is proposed based on the van Genuchten model, whereby SWCC hysteresis can be easily predicted from the initial drying SWCC. The theory for describing the main wetting curve and main drying curve considers the ink‐bottle effect and entrapped air. Laboratory experiments on silicon micro‐powder (SMP) and Guangxi Guiping clay (GGC) were conducted to determine SWCCs for five drying‐wetting cycles. The proposed equation was verified using the experimental SMP data and data from the literature. The predicted hysteretic SWCCs are in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

Epithelial-to-mesenchymal transition ( EMT) plays a significant role in tubulointerstitial fibrosis, which is a hallmark of diabetic nephropathy. Thus, identifying the mechanisms of EMT activation could be meaningful. In this study, loss of miR-30c accompanied with increased EMT was observed in renal tubules of db/db mice and cultured HK2 cells exposed to high glucose. To further explore the roles of miR-30c in EMT and tubulointerstitial fibrosis, recombinant adeno-associated viral vector was applied to manipulate the expression of miR-30c. In vivo study showed that overexpression of miR-30c suppressed EMT, attenuated renal tubulointerstitial fibrosis and reduced proteinuria, serum creatinine, and BUN levels. In addition, Snail1 was identified as a direct target of miR-30c by Ago2 co-immunoprecipitation, luciferase reporter, and Western blot assays. Downregulating Snail1 by si RNA reduced high glucose-induced EMT in HK2 cells, and miR-30c mimicked the effects. Moreover, miR-30c inhibited Snail1- TGF-β1 axis in tubular epithelial cells undergoing EMT and thereby impeded the release of TGF-β1; oppositely, knockdown of miR-30c enhanced the secretion of TGF-β1 from epitheliums and significantly promoted proliferation of fibroblasts and fibrogenesis of myofibroblasts, aggravated tubulointerstitial fibrosis, and dysfunction of diabetic nephropathy. These results suggest a protective role of miR-30c against diabetic nephropathy by suppressing EMT via inhibiting Snail1- TGF-β1 pathway. [ABSTRACT FROM AUTHOR]