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[Display omitted] • A phosphorylated bio-based chitosan functionalized MXene (PCS-MXene) was synthesized. • The TPU/PCS-MXene composites exhibited excellent thermal stability and mechanical performance. • The synergistic flame-retardant mechanism of MXene and phosphorylated chitosan in TPU were discussed and clarified. Recently, two-dimensional MXene demonstrated promising advantages to improve the flame-retardant performance of composites; however, its compatibility with polymer matrix is a great concern. In this study, MXene was first functionalized with phosphorylated chitosan (PCS) to obtain the PCS-MXene nanohybrid. The resulting nanohybrid was introduced into the thermoplastic polyurethane (TPU) matrix via solution mixing followed by the hot-pressing method, affording TPU/PCS-MXene nanocomposite. The resulting nanohybrid exhibited superior compatibility with the TPU matrix, enhancing mechanical performance of the TPU/PCS-MXene nanocomposite compared to the pristine TPU and TPU/MXene nanocomposite. Besides, the flame-retardant performance of TPU/PCS-MXene nanocomposite was greatly enhanced, while the smoke emission was effectively suppressed. As only 3 wt% PCS-MXene was introduced, peak heat release rate, total heat release, and total smoke production of the composite decreased by 66.7%, 21.0%, and 27.7%, respectively, compared to the pristine TPU. Systematical characterization was then carried out to investigate the enhancement mechanism of PCS-MXene, highlighting the crucial role of PCS combined with the catalytic effect of MXene. In brief, the compatibility issues of MXene were effectively addressed, and its flame-retardancy enhanced greatly via the PCS modification, the bio-based characteristic of which, in turn greatly benefits the further development of MXene-polymer composite. [ABSTRACT FROM AUTHOR]

This paper is devoted to studying in R n × (0 , T) (n ≥ 1) the Cauchy problem for a semilinear heat equation with source term f (x) non-rarefied at infinity, subjected to zero initial data. To such a problem, the novelty of this work lies in: (a) similar to no source case, non-rarefaction of f at infinity brings about its classical solution blowing up in a finite time T ⁎ > 0 ; (b) we derive the optimal upper and lower bound on the life span T ⁎. This may throw some light on studies of life span. [ABSTRACT FROM AUTHOR]

We consider L 2 -constraint minimizers of the mass critical Hartree energy functional with a trapping potential V ( x ) in a bounded domain Ω of R 4 . We prove that minimizers exist if and only if the parameter a > 0 satisfies a < a ⁎ = ‖ Q ‖ 2 2 , where Q > 0 is the unique positive solution of − Δ u + u − ( ∫ R 4 u 2 ( y ) | x − y | 2 d y ) u = 0 in R 4 . By investigating new analytic methods, the refined limit behavior of minimizers as a ↗ a ⁎ is analyzed for both cases where all the mass concentrates either at an inner point x 0 of Ω or near the boundary of Ω, depending on whether V ( x ) attains its flattest global minimum at an inner point x 0 of Ω or not. As a byproduct, we also establish two Gagliardo–Nirenberg type inequalities which are of independent interest. [ABSTRACT FROM AUTHOR]

Graphene hydrogel (GH) and aerogel (GA) have great application potential as highly effective adsorbents, but the accessibility of their adsorption sites have not yet been identified, restricting our understanding on the adsorption mechanisms and manufacturing. This study comparatively studied the adsorption characteristics of bisphenol A (BPA) and naphthalene (NAP) on GH and GA, focussing on the accessibility of the adsorption sites. The adsorption of BPA on GA was much lower but faster than that on GH. NAP adsorption on GA was very close to that on GH but faster than that on the latter. Considering that NAP is volatilisable, we speculate that some unwetted sites in the air-enclosed pores are available to it, but not to BPA. We applied ultrasonic and vacuum treatments to remove the air in GA pores, which was verified using a CO 2 replacement experiment. BPA adsorption was greatly enhanced but slowed, while that of NAP was not enhanced. This phenomenon suggested that some inner pores became accessible in the aqueous phase after air removal from pores. The enhanced accessibility of air-enclosed pores was verified by the increased relaxation rate of surface-bounded water on GA, based on a 1H NMR relaxation analysis. This study highlights that the accessibility of adsorption site plays a crucial role for the adsorption properties of carbon-based aerogel. The volatile chemicals may be quickly adsorbed in the air-enclosed pores, which be useful for immobilizing volatile contaminants. [Display omitted] • The adsorption of BPA on GA is lower but faster than that on GH. • NAP adsorption on GA is very close to that on GH but faster than that on the latter. • The higher adsorption on GH is depended on the higher adsorption site accessibility. • Ultrasonic or vacuum can enhance adsorption site accessibility of air-enclosed pores. • Increased relaxation rate of boundary water verifies the enhanced site accessibility. [ABSTRACT FROM AUTHOR]

• The vapor–liquid equilibrium of R1243zf in PEC7 and PEC9 were measured. • The NRTL model was utilized to model the experimental values. • Henry's law constants for the two mixtures were determined and analyzed. Vapor-liquid equilibrium measurements for 3, 3, 3‑trifluoropropene (R1243zf) with pentaerythritol tetraheptanoate (PEC7) and pentaerythritol tetranonanoate (PEC9) were performed using isochoric saturation method over temperatures from 278.15 K to 343.15 K and pressures up to 1.0 MPa. The experimental data were regressed by non-random two liquid (NRTL) activity coefficients model. In addition, the dissolving abilities of different refrigerants (R1243zf, R600a, RE170, R1234ze(E), R152a, R134a, R1234yf) in PEC7 and PEC9 were compared and analyzed. [ABSTRACT FROM AUTHOR]

Abstract: Aleutian mink disease virus (AMDV) is the only member in genus Amdovirus of the family Parvoviridae. During AMDV infection, six species of viral transcripts are generated from one precursor mRNA through alternative splicing and alternative polyadenylation. In addition to the large non-structural protein NS1, two small non-structural proteins, NS2 and NS3, are putatively encoded (Qiu J, et al., 2006. J. Virol. 80 654–662). However, these two proteins have not been experimentally demonstrated during virus infection, and nothing is known about their function. Here, we studied the nonstructural protein expression profile of AMDV, and for the first time, confirmed expression of NS2 and NS3 during infection, and identified their intracellular localization. More importantly, we provided evidence that both NS2 and NS3 are necessary for AMDV replication. [Copyright &y& Elsevier]

Abstract: Let and , and assume that f is a conformal map from into , with , then with , and is a moving frame on and it satisfies the following equation where ⋆ is the Hodge star operator on with respect to the standard metric. We will study the Dirichlet energy of this frame and give some applications. [Copyright &y& Elsevier]

Abstract: The controllable synthesis of novel dumbbell-like BiVO4 hierarchical nanostructures has been successfully obtained via a simple hydrothermal route. The as-synthesized products were studied by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and UV–vis absorption spectroscopy. The results showed that the nucleation and growth of the nanodumbbells were governed by an oriented aggregation growth mechanism. It is noteworthy that the concentration of poly(vinyl pyrrolidone) and the volume ratio of H2O to CH3COOH were crucial to the growth of the final nanoarchitectures. Control experiments were also carried out to investigate the factors which impact on the morphology of the products. Furthermore, the as-prepared BiVO4 hierarchical nanostructures demonstrated the superior visible-light-driven photocatalytic efficiency, which is helpful for the separation and recycle considering their promising applications in harmful pollutants disposal. [Copyright &y& Elsevier]

Abstract: We prove several basic properties for difference ascending chains, including a necessary and sufficient condition for an ascending chain to be the characteristic set of its saturation ideal and a necessary and sufficient condition for an ascending chain to be the characteristic set of a reflexive prime ideal. Based on these properties, we propose an algorithm to decompose the zero set of a finite set of difference polynomials into the union of zero sets of certain ascending chains. This decomposition algorithm is implemented and used to solve the perfect ideal membership problem, and to prove certain difference identities automatically. [Copyright &y& Elsevier]

Abstract: Coercive subtyping is a general approach to abbreviation and subtyping in dependent type theories with inductive types. Coherence and admissibility of transitivity are important both for understanding of the framework and for its correct implementation. In this paper, we study the issue of transitivity in the context of subtyping for parameterised inductive types. In particular, we propose and study the notion of weak transitivity and show that, for a large class of parameterised inductive types, the natural subtyping rules are coherent and weak transitivity is admissible in an intensional type theory. A possible extension of type theory with certain extensional computation rules is also discussed for achieving admissibility of transitivity in general. [Copyright &y& Elsevier]

To investigate the impact and mechanism of Cd-tolerant bacteria in soil on promoting Cd accumulation in Ageratum conyzoides L., we verified the impact of inoculating two strains, B-1 (Burkholderia contaminans HA09) and B-7 (Arthrobacter humicola), on Cd accumulation in A. conyzoides through a pot experiment. Additionally, we investigated the dissolution of CdCO 3 and nutrient elements, as well as the release of indoleacetic acid (IAA) by the two strains. The results showed that both strains can significantly improve the dissolution of CdCO 3. Strains B-1 and B-7 had obvious effect of dissolving phosphorus, which was 5.63 and 2.76 times higher than that of the control group, respectively. Strain B-7 had significant effect of dissolution potassium, which was 1.79 times higher than that of the control group. Strains B-1 and B-7 had significant nitrogen fixation effect, which was 29.53 and 44.39 times higher than that of the control group, respectively. In addition, inoculating with strain B-1 and B-7 significantly increased the Cd extraction efficiency of A. conyzoides (by 114% and 45% respectively) through enhancing Cd accumulation and the biomass of A. conyzoides. Furthermore, the inoculation of strain B-1 and B-7 led to a significant increase in the activities of CAT and SOD, as well as the content of chlorophyll a and total chlorophyll in the leaves of A. conyzoides. To sum up, strain B-1 and B-7 can promote the phytoremediation efficiency of A. conyzoides on Cd by promoting the biomass and Cd accumulation of A. conyzoides. [Display omitted] • Strain B-1 and B-7 raised Cd extraction by A. conyzoides by 114% and 45%. • Strains boosts Cd remediation by promoting biomass and Cd extraction of A. conyzoides. • Strain B-1 and B-7 can release a large amount of IAA. • Strain B-1 and B-7 can promote the release of nutrition (such as N, P and K). [ABSTRACT FROM AUTHOR]

Abstract: Among the six classes of Zeeman''s classification for three-dimensional Lotka–Volterra competitive systems with limit cycles, besides the classes 26, 27, 28 and 29, multiple limit cycles are found in classes 30 and 31 by an algorithmic method proposed by Hofbauer and So [J. Hofbauer, J.W. So, Multiple limit cycles for three-dimensional Lotka–Volterra equations, Appl. Math. Lett. 7 (1994) 65–70]. This also gives an answer to a problem proposed in [J. Hofbauer, J.W. So, Multiple limit cycles for three-dimensional Lotka–Volterra equations, Appl. Math. Lett. 7 (1994) 65–70]. [Copyright &y& Elsevier]

Mitochondrial metabolism plays a pivotal role in various cellular processes and fibrosis. However, the mechanism underlying mitochondrial metabolic function and liver fibrosis remains poorly understood. In this study, we determined whether mitochondrial metabolism mediates liver fibrosis using cells, animal models, and clinical samples to elucidate the potential effects and underlying mechanism of mitochondrial metabolism in liver fibrosis. We report that AlkB Homolog 5 (ALKBH5) decreases mitochondrial membrane potential (MMP) and oxygen consumption rate (OCR), suppresses mitochondrial fission and hepatic stellate cell (HSC) proliferation and migration and ameliorates liver fibrosis. Enhancement of mitochondrial fission, an essential event during HSC proliferation and migration, is dependent on decreased ALKBH5 expression. Furthermore, we reveal that low ALKBH5 expression is associated with elevated N6-methyladenosine (m6A) mRNA levels. Mechanistically, ALKBH5 mediates m6A demethylation in the 3'UTR of Drp1 mRNA and induces its translation in a YTH domain family proteins 1 (YTHDF1)-independent manner. Subsequently, in transforming growth factor-β1 (TGF-β1) induced HSC, Dynamin-related protein 1 (Drp1) mediates mitochondrial fission and increases cell proliferation and migration. Decreased Drp1 expression inhibits mitochondrial fission and suppresses HSC proliferation and migration. Notably, human fibrotic liver and heart tissue exhibited enhanced mitochondrial fission; increased YTHDF1, Drp1, alpha-smooth muscle actin (α-SMA) and collagen I expression; decreased ALKBH5 expression and increased liver fibrosis. Our results highlight a novel mechanism by which ALKBH5 suppresses mitochondrial fission and HSC proliferation and migration by reducing Drp1 methylation in an m6A-YTHDF1-dependent manner, which may indicate a demethylation-based approach for liver fibrosis diagnosis and therapy. [Display omitted] • Crucial roles of Drp1 in TGF-β1 induced HSC proliferation and migration and mitochondrial fission. • ALKBH5 mediated m6A demethylation in the 3'UTR of Drp1 mRNA and induced its translation. • ALKBH5 loss upregulated Drp1 levels in an m6A-YTHDF1-dependent manner. [ABSTRACT FROM AUTHOR]

Abstract: We have generated a quantitative transcription profile of human bocavirus type 1 (HBoV1) by transfecting a nearly full-length clone in human lung epithelial A549 cells as well as in a replication competent system in 293 cells. The overall transcription profile of HBoV1 is similar to that of two other members of genus Bocavirus, minute virus of canines and bovine parvovirus 1. In particular, a spliced NS1-transcript that was not recognized previously expressed the large non-structural protein NS1 at approximately 100kDa; and the NP1-encoding transcripts were expressed abundantly. In addition, the protein expression profile of human bocavirus type 2 (HBoV2) was examined in parallel by transfection of a nearly full-length clone in A549 cells, which is similar to that of HBoV1. Moreover, our results showed that, unlike human parvovirus B19 infection, expression of the HBoV1 proteins only does not induce cell cycle arrest and apoptosis of A549 cells. [Copyright &y& Elsevier]