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In this work, Ni and NiFe LDH are coupled on a carbon cloth to synthesize flexible electrocatalysts with superhydrophilic interfaces. DFT calculations demonstrate that the formation of a unique heterostructure induce the redistribution of the surrounding electrons and increase the total density of states near the Fermi energy level, which optimized the Gibbs free energy for hydrogen adsorption. Under alkaline conditions, the HER overpotential is only 36 mv at a current density of 10 mA cm−2, which is fully comparable to noble metal catalysts. [Display omitted] The rational design of morphology and heterogeneous interfaces for non-precious metal electrocatalysts is crucial in electrochemical water decomposition. In this paper, a bifunctional electrocatalyst (Ni/NiFe LDH), which coupling nickel with nickel–iron layer double hydroxide (NiFe LDH), is synthesized on carbon cloth. At current density of 10 mA cm−2, the Ni/NiFe LDH exhibits a low hydrogen evolution reaction (HER) overpotential of only 36 mV due to the accelerated electrolyte penetration, which is caused by superhydrophilic interface. Moreover, an alkaline electrolyzer is formed and provide a current density of 10 mA cm−2 with a voltage of only 1.49 V. It is confirmed by the density functional theory (DFT) that electron from the Ni layer is transferred to NiFe LDH layer, redistributing the local electron density around the heterogeneous phase interface. Thus, the Gibbs free energy for hydrogen adsorption is optimized. This work provides a promising strategy for the rational regulation of electrons at heterogeneous interfaces and the synthesis of flexible electrocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] In this paper, we have developed a simple and efficient sulfur-amine chemistry strategy to prepare a three-dimensional (3D) porous Ti 3 C 2 T x composite with large amounts of N and S terminal groups. The well-designed 3D macroporous architecture presents enlarged interlayer spacing, large specific surface area, and unique porous structure, which successfully solves the re-stacking issue of MXene during storage and electrode fabrication. It is the amount of concentrated hydrochloric acid added to the S-EDA (ethylenediamine)/MXene colloidal suspension that is critical to the formation of 3D morphology. In addition, N and S terminals on MXene could improve the adsorption ability of K+. Owing to the synergistic effect of the structure design and terminal modification, the N, S codoped three-dimensional porous Ti 3 C 2 T x (3D-NSPM) material shows a high surface capacitive contribution and rapid diffusion kinetics for K+ and Na+. As a result, the as-prepared 3D-NSPM delivers high reversible capacity (237 and 273 mAh g−1 at 0.1 A g−1 for PIBs and SIBs, respectively), superb cycling stability (84.9% capacity retention after 10,000 cycles at 1 A g−1 in PIBs and 74.0% capacity retention after 2200 cycles at 1 A g−1 in SIBs), and excellent rate capability (111 and 196 mAh g−1 at 5 A g−1 for PIBs and SIBs, respectively), which are superior to other MXene-based anodes for PIBs and SIBs. Moreover, the described strategy provides a new insight for constructing the 3D porous structure from 2D building blocks beyond MXene. [ABSTRACT FROM AUTHOR]

Pb SA -Cu/PC with a three-dimensional structure was demonstrated as an efficient CO 2 reduction catalyst to formate. Pb inhibited the formation of COOH*, reduced the energy barrier of rate determining step in the formate formation process, and achieved 97% high formate selectivity. [Display omitted] • Pb SA100 -Cu/CP catalyst is developed by an economical and low-energy method. • The FE formate is 97 % with a partial current density of 27.9 mA cm−2 at − 0.9 V. • The catalyst exhibits ultra-long stability for more than 60 h. • The synergistic action of Pb SA and Cu atoms lowers the RDS for CO 2 RR to fromate. • Single-atom Pb induces Cu charge redistribution and inhibits the formation of COOH*. Exploring highly selective and stable electrocatalysts is of great significance for the electrochemical conversion of CO 2 into fuel. Herein, a three-dimensional (3D) nanostructure catalyst was developed by doping Pb single-atom (Pb SA) in-situ on carbon paper (Pb SA100 -Cu/CP) through a low-energy and economical method. The designed catalyst exhibited abundant active sites and was beneficial to CO 2 adsorption, activation, and subsequent conversion to fuel. Interestingly, Pb SA100 -Cu/CP showed a prominent Faraday efficiency (FE) of 97 % at –0.9 V versus reversible hydrogen electrode (vs. RHE) and a high partial current density of 27.9 mA·cm−2 for formate. Also, the catalyst remained significantly stable for 60 h during the durability test. The reaction mechanism was investigated by density functional theory (DFT), demonstrating that the doping Pb SA induced the electrons redistribution, promoted the formate generation, reduced the rate-determining step (RDS) energy barrier, and inhibited the hydrogen evolution reaction. The study aims to provide a new strategy for developing of single-atom catalysts with high selectivity and stability, which will help reduce environmental pressure and alleviate energy problems. [ABSTRACT FROM AUTHOR]

[Display omitted] Electrochemiluminescence (ECL) biosensors provide a convenient and high sensitivity method for early disease diagnosis. However, creating luminophore arrays relying on powerful ECL signals remains a daunting task. Porphyrin-centered metal organic frameworks (MOFs) exhibit remarkable potential in ECL sensing applications. In this paper, based on a simple one-pot synthesis method, PCN-222@Ag NPs doped with CeO 2 was synthesized to enhance the ECL performance. Due to the strong catalytic ability of CeO 2 , the ECL signal strength of the new material PCN-222@CeO 2 @Ag NPs is much higher than that of the PCN-222@Ag NPs and PCN-222. The luminous properties of PCN-222@CeO 2 @Ag NPs become more intense and stable due to the excellent electronic conductivity of Ag NPs. Based on the fact that CuS@PDA composite can quench the ECL signal of PCN-222@CeO 2 @Ag NPs, we constructed a novel sandwich ECL immune sensor for the detection of phosphorylated Tau 181 (p-Tau-181) protein. The ECL sensor has a great linear relationship with p-Tau-181 protein concentration, ranging from 1 pg/mL to 100 ng/mL. The detection limit is as low as 0.147 pg/mL. This work provides new ideas for developing sensitive ECL sensors for the p-Tau-181 protein, the marker of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

In this paper we study the asymptotic dynamics for a class of semilinear parabolic problems with Dirichlet boundary conditions in domains with a small hole of size proportional to a positive parameter ε. In other words, we prove that the family of attractors behaves continuously as ε → 0. We will also provide the convergence rates in terms of the parameter. [ABSTRACT FROM AUTHOR]

This paper studies the zero-viscosity limit for the Navier-Stokes equations with rotation, an additive white noise and nonslip boundary condition in dimension three. By establishing the well-posedness of the limit problems and constructing approximate solutions, we obtain the convergence in the mean square for the Oseen type equation with nonlinear source term, and the convergence in probability of the martingale solution of the stochastic Navier-Stokes equations with rotation. [ABSTRACT FROM AUTHOR]

A modified Poisson–Nernst–Planck system in a bounded domain with mixed Dirichlet–Neumann boundary conditions is analyzed. It describes the concentrations of ions immersed in a polar solvent and the correlated electric potential due to the ion–solvent interaction. The concentrations solve cross-diffusion equations, which are thermodynamically consistent. The considered mixture is saturated, meaning that the sum of the ion and solvent concentrations is constant. The correlated electric potential depends nonlocally on the electric potential and solves the fourth-order Poisson–Fermi equation. The existence of global bounded weak solutions is proved by using the boundedness-by-entropy method. The novelty of the paper is the proof of the weak–strong uniqueness property. In contrast to the existence proof, we include the solvent concentration in the cross-diffusion system, leading to a diffusion matrix with nontrivial kernel. Then the proof is based on the relative entropy method for the extended cross-diffusion system and the positive definiteness of a related diffusion matrix on a subspace. [ABSTRACT FROM AUTHOR]

This paper is concerned with the pathwise dynamics of stochastic p -Laplacian lattice systems driven by Wong-Zakai type approximation noises. The existence and uniqueness of pullback random attractor are established for the approximate system with a wide class of nonlinear diffusion term. When the stochastic system is driven by a linear multiplicative noise, we prove the convergence of solutions and the upper semicontinuity of random attractors for Wong-Zakai approximations as the step-length of the Wiener shift approaches zero. [ABSTRACT FROM AUTHOR]

This paper deals with the coupled fourth-order parabolic equations, subject to Dirichlet or Navier boundary conditions. We combine the generalized potential well method, the concave method, with the auxiliary methods to classify the initial energy about the existence of blow-up solutions and global solutions. Moreover, the decay estimate of global solutions and the bounds of blow-up time and rate are determined, respectively. [ABSTRACT FROM AUTHOR]

The maximum number of centers is an open problem proposed by Gasull for planar polynomial differential systems of degree n with n ≥ 4. In this paper we study the problem for planar polynomial Kolmogorov differential systems of degree n , prove that the maximum number of centers is exactly seven for planar quartic polynomial Kolmogorov differential systems, and give the upper and lower bound for the maximum number of centers that the Kolmogorov differential systems of degree n can have. [ABSTRACT FROM AUTHOR]

This paper concerns the structural stability of subsonic steady-states to the bipolar Euler-Poisson equations under small perturbation of doping profiles. Here, the electron density is imposed with degenerate sonic boundary and considered in interiorly subsonic case, while the hole density is considered in fully subsonic case. Unlike the unipolar model, we show that the structural stability in bipolar model holds regardless of the type of doping profile and propose a new version of comparison principle, which captures the intrinsic negative correlation between electrons and holes. To overcome the difficulty caused by the degenerate effect at the sonic boundary, we introduce two different weight functions to handle the singularity near both sides of endpoints separately. The approaches adopted to prove the structural stability include the local singularity analysis, the monotonicity method, the continuation argument and the squeezing skill. Several numerical simulations are performed which support our theoretical results. [ABSTRACT FROM AUTHOR]

This paper is concerned with the Cauchy problem of the quadratic nonlinear Schrödinger equation in R × R 2 with the nonlinearity η | u | 2 where η ∈ C ∖ { 0 } and low regularity initial data. If s < − 1 / 4 , the ill-posedness result in the Sobolev space H s (R 2) is known. We will prove the well-posedness in H s (R 2) for − 1 / 2 < s < − 1 / 4 by assuming some angular regularity on initial data. The key tools are the modified Fourier restriction norm and the convolution estimate on thickened hypersurfaces. [ABSTRACT FROM AUTHOR]

In this paper we study the harmonic map heat flow on the euclidean space R d and we show an unconditional uniqueness result for maps with small initial data in the homogeneous Besov space B ˙ p , ∞ d p (R d) where d < p < ∞. As a consequence we obtain decay rates for solutions of the harmonic map flow of the form ‖ ∇ u (t) ‖ L ∞ (R d) ≤ C t − 1 2 . Additionally, under the assumption of a stronger spatial localization of the initial conditions, we show that the temporal decay happens in a self-similar way. We also explain that similar results hold for the biharmonic map heat flow and the semilinear heat equation with a power-type nonlinearity. [ABSTRACT FROM AUTHOR]

We are interested in the global dynamics of a massive scalar field evolving under its own gravitational field and, in this paper, we study spherically symmetric solutions to Einstein's field equations coupled with a Klein-Gordon equation with quadratic potential. For the initial value problem we establish a global existence theory when initial data are prescribed on a future light cone with vertex at the center of symmetry. A suitably generalized solution in Bondi coordinates is sought which has low regularity and possibly large but finite Bondi mass. A similar result was established first by Christodoulou for massless fields. In order to deal with massive fields, we must overcome several challenges and significantly modify Christodoulou's original method. First of all, we formulate the Einstein-Klein-Gordon system in spherical symmetry as a non-local and nonlinear hyperbolic equation and, by carefully investigating the global dynamical behavior of the massive field, we establish various estimates concerning the Einstein operator, the Hawking mass, and the Bondi mass, including novel positivity and monotonicity properties. Importantly, in addition to a regularization at the center of symmetry we find it necessary to also introduce a regularization at null infinity. We also establish new energy and decay estimates for, both, regularized and generalized solutions. [ABSTRACT FROM AUTHOR]

In this paper, we study the long time dynamical behavior of the solutions for d -dimensional nonlinear Schödinger equation with general nonlinearity by using Birkhoff normal form technique and the so-called tame property in Gevrey space and modified Sobolev space. [ABSTRACT FROM AUTHOR]

We study an imbibition problem for porous media. When a wetted layer is above a dry medium, gravity leads to the propagation of the water downwards into the medium. In experiments, the occurrence of fingers was observed, a phenomenon that can be described with models that include hysteresis. In the present paper we describe a single finger in a moving frame and set up a free boundary problem to describe the shape and the motion of one finger that propagates with a constant speed. We show the existence of solutions to the travelling wave problem and investigate the system numerically. [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]

In this paper, we study the existence and stability of concentrated traveling-rotating helical vortex for the 3D incompressible Euler equations in an infinite pipe. The solutions are obtained by maximization of the energy over the set of rearrangments of a fixed bounded function with compact support, and tends asymptotically to singular helical vortex filament evolving by the binormal curvature flow. We also show nonlinear stability of maximizers under L p perturbation for p ≥ 2. [ABSTRACT FROM AUTHOR]

[Display omitted] • Eco-design of a highly efficient Cr(VI) adsorbent with bimodal micro-/mesoporous structure. • Green synthesis approach utilizing Sorghum waste as a sustainable silica source for the adsorbent. • A one-pot synthesis method led to homogeneously distributed adsorption sites on the MI-Cl-FDU-12. • MI-Cl-FDU-12 demonstrated a high adsorption capacity of 416.9 mg g-1 at 313 K for Cr(VI) • MI-Cl-FDU-12 adsorbent revealed excellent regeneration performance by six consecutive cycles. This paper presents an eco-design approach to the synthesis of a highly efficient Cr(VI) adsorbent, utilizing a positively charged surface mesoporous FDU-12 material (designated as MI-Cl-FDU-12) for the first time. The MI-Cl-FDU-12 anion-exchange adsorbent was synthesized via a facile one-pot synthesis approach using sodium silicate extracted from sorghum waste as a green silica source, 1-methyl-3-(triethoxysilylpropyl) imidazolium chloride as a functionalization agent, triblock copolymer F127 as a templating or pore-directing agent, trimethyl benzene as a swelling agent, KCl as an additive, and water as a solvent. The synthesis method offers a sustainable and environmentally friendly approach to the production of a so-called "green" adsorbent with a bimodal micro-/mesoporous structure and a high surface area comparable with the previous reports regarding FDU-12 synthesis. MI-Cl-FDU-12 was applied as an anion exchanger for the adsorption of toxic Cr(VI) oxyanions from aqueous media and various kinetic and isotherm models were fitted to experimental data to propose the adsorption behavior of Cr(VI) on the adsorbent. Langmuir model revealed the best fit to the experimental data at four different temperatures, indicating a homogeneous surface site affinity. The theoretical maximum adsorption capacities of the adsorbent were found to be 363.5, 385.5, 409.0, and 416.9 mg g−1 at 298, 303, 308, and 313 K, respectively; at optimal conditions (pH=2, adsorbent dose=3.0 mg, and contact time of 30 min), surpassing that of most previously reported Cr(VI) adsorbents in the literature. A regeneration study revealed that this adsorbent possesses outstanding performance even after six consecutive recycling. [ABSTRACT FROM AUTHOR]

In this paper, we study the Cauchy problem for the one-dimensional Euler-Poisson (or hydrodynamic) model for semiconductors, where the energy equation is replaced by a pressure-density relation. First, the existence of global entropy solutions is proved by using the vanishing artificial viscosity method, where, a special flux approximate is introduced to ensure the uniform boundedness of the electric field E and the a-priori L ∞ estimate, 0 < 2 δ ≤ ρ ε , δ ≤ M (t) , | u ε , δ | ≤ M (t) , where M (t) could tend to infinity as the time t tends to infinity, on the viscosity-flux approximate solutions (ρ ε , δ , u ε , δ) ; Second, the compensated compactness theory is applied to prove the pointwise convergence of (ρ ε , δ , u ε , δ) as ε , δ go to zero, and that the limit (ρ (x , t) , u (x , t)) is a global entropy solution; Third, a technique, to apply the maximum principle to the combination of the Riemann invariants and ∫ − ∞ x ρ ε , δ (x , t) − 2 δ d x , deduces the uniform L ∞ estimate, 0 < 2 δ ≤ ρ ε , δ ≤ M , | u ε , δ | ≤ M , independent of the time t and ε , δ ; Finally, as a by-product, the known compactness framework [14,29] is applied to show the relaxation limit, as the relation time τ and ε , δ go to zero, for general pressure P (ρ). [ABSTRACT FROM AUTHOR]

This paper presents the global stability and the large-time behavior of solutions to the compressible Oldroyd-B model in a periodic domain. Moreover, we show that the H 3 -norm of the solutions decays exponentially in time. It is worth pointing out that the coupling parameter ω is not necessary to be small enough in our result. [ABSTRACT FROM AUTHOR]

The paper is devoted to investigating the well-posedness, stability and large-time behavior near the hydrostatic balance for the 2D Boussinesq equations with partial dissipation. More precisely, the global well-posedness is obtained in the case of partial viscosity and without thermal diffusion for the initial data belonging to H δ (R 2) × H s (R 2) for δ ∈ [ s − 1 , s + 1 ] if s ∈ R , s > 2 , for δ ∈ (1 , s + 1 ] if s ∈ (0 , 2 ] and for δ ∈ [ 0 , 1 ] if s = 0. In addition, if one has either horizontal or vertical thermal diffusion then the stability and large-time behavior are provided in H m (R 2) , m ∈ N and in H ˙ m − 1 (R 2) with m ∈ N , m ≥ 2 , respectively. [ABSTRACT FROM AUTHOR]

This paper aims to study a semilinear transfer equation with a delay term defined over a non-cylindrical domain. We prove the existence and regularity of weak solutions as well as the existence, regularity and finiteness of the fractal dimension of pullback attractors on tempered universes that depend on a non-increasing function. We address the problem of estimating the fractal dimension of pullback attractors, under current techniques, which consists of readjusting the proof presented in [9, Lemma 1.3] and extending it to families of normed spaces parameterized in time, see Theorem 4.11. [ABSTRACT FROM AUTHOR]

To accurately predict and evaluate the performance of the crushing device of no-till planter, it is strongly necessary to establish an accurate interaction model of the straw-crushing device coupling system. The traditional model has low prediction accuracy and cannot simulate the fracture characteristics of the straw during the operation of the crushing device due to the straw being usually regarded as a rigid body or a combination of rigid ball joints. In this paper, a breakable and flexible hollow straw model is first proposed and a CFD-DEM coupling model of the straw group-crushing device considering the effect of gas-solid two phase is also established. Afterwards, the corresponding verification experiments are conducted and the effect of working and structural parameters on the straw-throwing weight and crushing length is also analysed. It is demonstrated that the relative error between the simulation results and the experimental results for the straw crushing length is 7.7%, and the relative error for the straw-throwing weight is 7.1%, thereby verifying the correctness of the CFD-DEM model. Finally, the response surface method is also used to determine the optimal working and structural parameters of the crushing device and corresponding field tests verification is also conducted. Results indicate that the optimal parameter combination is as: the rotational speed of the crushing spindle is 2400 rpm, the inlet clearance is 30 mm and the starting point angle is 45°. Moreover, the crushing length after optimisation is 6.6% smaller than before optimisation, and the straw-throwing weight is increased by 11.5%. [Display omitted] • A breakable and flexible hollow straw model is proposed. • A CFD-DEM coupling model of the straw group-crushing device is also established. • RSM is used to determine the optimal working and structural parameters. • Both the fracture characteristics of straw and airflow field are also considered. [ABSTRACT FROM AUTHOR]

In this paper, we study universal sums of triangular numbers and squares. Specifically, we prove that a sum of triangular numbers and squares is universal if and only if it represents 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 10 , 13 , 14 , 15 , 18 , 19 , 20 , 23 , 27 , 28 , 34 , 41 , 47 , and 48. [ABSTRACT FROM AUTHOR]

In this paper we classify all monic, quartic, polynomials d (x) ∈ Z [ x ] for which the Pell equation f (x) 2 − d (x) g (x) 2 = 1 has a non-trivial solution with f (x) , g (x) ∈ Z [ x ]. [ABSTRACT FROM AUTHOR]

It is known that any Galois representation ρ : G Q → GL (2 , F p) with determinant equal to the mod- p cyclotomic character, arises from the p -torsion of an elliptic curve over Q , if and only if p ≤ 5. In dimension g = 2 , when p ≤ 3 , it is again known that any Galois representation valued in GSp (4 , F p) with cyclotomic similitude character arises from an abelian surface. In this paper, we study this question for all primes p and dimensions g ≥ 2. When g ≥ 2 and (g , p) ≠ (2 , 2) , (2 , 3) , (3 , 2) , we prove the existence of a Galois representation over Q valued in GSp (2 g , F p) with cyclotomic similitude character, that cannot arise as the p -torsion representation of any g -dimensional abelian variety over Q. [ABSTRACT FROM AUTHOR]

In any dimension d ≥ 2 , there is no known example of a low-discrepancy sequence which possesses Poisssonian pair correlations. This is in some sense rather surprising, because low-discrepancy sequences always have β -Poissonian pair correlations for all 0 < β < 1 d and are therefore arbitrarily close to having Poissonian pair correlations (which corresponds to the case β = 1 d). In this paper, we further elaborate on the closeness of the two notions. We show that d -dimensional Kronecker sequences for badly approximable vectors α → with an arbitrary small uniformly distributed stochastic error term generically have β = 1 d -Poissonian pair correlations. [ABSTRACT FROM AUTHOR]

Let N k (m , n) denote the number of partitions of n with Garvan k -rank m. It is well-known that Andrews–Garvan–Dyson's crank and Dyson's rank are the k -rank for k = 1 and k = 2 , respectively. In this paper, we prove that the sequences (N k (m , n)) | m | ≤ n − k − 71 are log-concave for all sufficiently large integers n and each integer k. In particular, we partially solve the log-concavity conjecture for Andrews–Garvan–Dyson's crank and Dyson's rank, which was independently proposed by Bringmann–Jennings-Shaffer–Mahlburg and Ji–Zang recently. [ABSTRACT FROM AUTHOR]

Let U q (g) denote the rational form of the quantized enveloping algebra associated to a complex simple Lie algebra g. Let λ be a nonzero dominant integral weight of g , and let V be the corresponding type 1 finite-dimensional irreducible representation of U q (g). Starting from this data, the R -matrix formalism for quantum groups outputs a Hopf algebra U R λ (g) defined in terms of a pair of generating matrices satisfying well-known quadratic matrix relations. In this paper, we prove that this Hopf algebra admits a Chevalley–Serre type presentation which can be recovered from that of U q (g) by adding a single invertible quantum Cartan element. We simultaneously establish that U R λ (g) can be realized as a Hopf subalgebra of the tensor product of the space of Laurent polynomials in a single variable with the quantized enveloping algebra associated to the lattice generated by the weights of V. The proofs of these results are based on a detailed analysis of the homogeneous components of the matrix equations and generating matrices defining U R λ (g) , with respect to a natural grading by the root lattice of g compatible with the weight space decomposition of End (V). [ABSTRACT FROM AUTHOR]

Semi-standard graded rings are a generalized notion of standard graded rings. In this paper, we compare generalized notions of the Gorenstein property in semi-standard graded rings. We discuss the commonalities between standard graded rings and semi-standard graded rings, as well as elucidate distinctive phenomena present in semi-standard graded rings that are absent in standard graded rings. [ABSTRACT FROM AUTHOR]

In this paper, a symplectic structure on a Leibniz algebra is defined to be a symmetric nondegenerate bilinear form satisfying certain compatibility condition, and a phase space of a Leibniz algebra is defined to be a symplectic Leibniz algebra satisfying certain conditions. We show that a Leibniz algebra has a phase space if and only if there is a compatible Leibniz-dendriform algebra, and phase spaces of Leibniz algebras are one-to-one corresponds to Manin triples of Leibniz-dendriform algebras. Product (paracomplex) structures and complex structures on Leibniz algebras are studied in terms of decompositions of Leibniz algebras. A para-Kähler structure on a Leibniz algebra is defined to be a symplectic structure and a paracomplex structure satisfying a compatibility condition. We show that a symplectic Leibniz algebra admits a para-Kähler structure if and only if the Leibniz algebra is the direct sum of two Lagrangian subalgebras as vector spaces. A complex product structure on a Leibniz algebra consists of a complex structure and a product structure satisfying a compatibility condition. A pseudo-Kähler structure on a Leibniz algebra is defined to be a symplectic structure and a complex structure satisfying a compatibility condition. Various properties and relations of complex product structures and pseudo-Kähler structures are studied. In particular, Leibniz-dendriform algebras give rise to complex product structures and pseudo-Kähler structures naturally. [ABSTRACT FROM AUTHOR]

Let G be an infinite simple group of finite Morley rank and of Prüfer 2-rank 1 which admits a supertight automorphism α such that the fixed-point subgroup C G (α n) is pseudofinite for all integers n > 0. The main result of this paper is the identification of G with PGL 2 (K) for some algebraically closed field K of characteristic ≠2. [ABSTRACT FROM AUTHOR]

There are several classical characterisations of the valuative dimension of a commutative ring. Constructive versions of this dimension have been given and proven to be equivalent to the classical notion within classical mathematics, and they can be used for the usual examples of commutative rings. To the contrary of the classical versions, the constructive versions have a clear computational content. This paper investigates the computational relationship between three possible constructive definitions of the valuative dimension of a commutative ring. In doing so, it proves these constructive versions to be equivalent within constructive mathematics. [ABSTRACT FROM AUTHOR]

To prove that a modular variety is of general type, there are three types of obstructions: reflective, cusp and elliptic obstructions. In this paper, we give a quantitative estimate of the reflective obstructions for the unitary case. This shows in particular that the reflective obstructions are small enough in higher dimension, say greater than 138. Our result reduces the study of the Kodaira dimension of unitary modular varieties to the construction of a cusp form of small weight in a quantitative manner. As a byproduct, we formulate and partially prove the finiteness of Hermitian lattices admitting reflective modular forms, which is a unitary analog of the conjecture by Gritsenko-Nikulin in the orthogonal case. Our estimate of the reflective obstructions uses Prasad's volume formula. [ABSTRACT FROM AUTHOR]

Resolvent degree is an invariant measuring the complexity of algebraic and geometric phenomena, including the complexity of finite groups. To date, the resolvent degree of a finite simple group G has only been investigated when G is a cyclic group; an alternating group; a simple factor of a Weyl group of type E 6 , E 7 , or E 8 ; or PSL (2 , F 7). In this paper, we establish upper bounds on the resolvent degrees of the sporadic groups by using the invariant theory of their projective representations. To do so, we introduce the notion of (weak) RD k ≤ d -versality, which we connect to the existence of "special points" on varieties. [ABSTRACT FROM AUTHOR]

The solubilizer of an element x of a profinite group G is the set of the elements y of G such that the subgroup of G generated by x and y is prosoluble. We propose the following conjecture: the solubilizer of x in G has positive Haar measure if and only if x centralizes 'almost all' the non-abelian chief factors of G. We reduce the proof of this conjecture to another conjecture concerning finite almost simple groups: there exists a positive c such that, for every finite simple group S and every (a , b) ∈ (Aut (S) ∖ { 1 }) × Aut (S) , the number of s is S such that 〈 a , b s 〉 is insoluble is at least c | S |. Work in progress by Fulman, Garzoni and Guralnick is leading to prove the conjecture when S is a simple group of Lie type. In this paper we prove the conjecture for alternating groups. [ABSTRACT FROM AUTHOR]

In [16] , a theory of universal extensions in abelian categories is developed; in particular, the notion of Ext 1 -universal object is presented. In the present paper, we show that an Ab3 abelian category which is Ext 1 -small satisfies the Ab4 condition if, and only if, each one of its objects is Ext 1 -universal. We use the dual of this result to construct projective effacements in Grothendieck categories. In particular, we complete the classical result of Roos on Grothendieck categories which are Ab4*, with a new proof, independent of [20]. We also give a characterization of the co- Ext 1 -universal objects of the category of torsion abelian groups. In particular, we show that such groups are the ones admitting a decomposition Q ⊕ R , in which Q is injective and R is a reduced group in which each p -component is bounded. [ABSTRACT FROM AUTHOR]

In this paper we study the classifying spaces of graph products of simplicial groups and connected Hopf algebras over a field, and show that they can be uniformly treated under the framework of polyhedral products. It turns out that these graph products are models of the loop spaces of polyhedral products over a flag complex and their homology, respectively. Certain morphisms between graph products are also considered. In the end we prove the structure theorems of such graph products in the form we need. [ABSTRACT FROM AUTHOR]

In this paper we mainly consider the notion of Drinfeld double for two weak multiplier Hopf (⁎-)algebras which are paired with each other. Then we show that the Drinfeld double is again a weak multiplier Hopf (⁎-)algebra. Furthermore, we study integrals on the Drinfeld double. Finally, we establish the correspondence between modules over a Drinfeld double D (A) and Yetter-Drinfeld modules over a weak algebraic quantum group A. [ABSTRACT FROM AUTHOR]

Ovarian cancer (OC) is a global health problem, and the mortality-to-incidence ratio is expected to increase, especially in low- and middle-income countries. These regions face disparities in access to OC care, including lack of awareness, limited access to genetic and tumor testing, paucity of surgical expertise, time to approval of novel therapeutics, and treatment costs. By addressing these inequities, the core aim of this paper is to promote action through collaboration in order to overcome these barriers and promote health equity in OC management and treatment. • Rising mortality to incidence ratio in ovarian cancer is expected, related to limited access in low and middle income areas. • Data reflecting population heterogeneity, genetic testing, drug access, and clinical trial diversity need to be prioritized. • Unite international team of health care providers in order to promote global equity in ovarian cancer care. [ABSTRACT FROM AUTHOR]

There is very little research on German colonial geography in general, and the boom in this subdiscipline during the National Socialist period has not received any scholarly attention so far. Against that backdrop, this paper aims to contribute: a) to a finer-grained picture of colonial, racial-Völkish thinking – and its application – in German geography during the National Socialist period and b) to our understanding of the continuities and ruptures in German geographical scholarship after WWII. To that end, I focus on the biography of Oskar Schmieder (1891–1980). Two interrelated aspects of Schmieder's writings will guide the analysis: first, his conceptualization of race, Volk , and soil regarding (Germans in) South America and, secondly, the political colonial project that he pursued for Nazi Germany. Studying Oskar Schmieder shows that German geographers not only stood up for the re-establishment of a German colonial empire during the National Socialist period, but also fought for its Fascist orientation – which, at least for Schmieder, was to differ from the German colonial pre-1914 empire. Being primarily known as a representative of Länderkunde , Schmieder's institutionally and conceptually influential career after 1945 can be seen as a prime example of the continuities within the discipline in Germany. • Investigates the biography of German colonial geographer Oskar Schmieder. • Shows how Schmieder interpreted (German) settler colonialism in Latin America. • Analyzes the ascent of German colonial geography during National Socialism. • Contributes to our knowledge of geographer's contribution to colonialization efforts. • Analyzes continuities in German geography before and after WWII. [ABSTRACT FROM AUTHOR]

Wetland reclamation was an intrinsic part of nineteenth-century global agricultural transformations. In Swedish research, reclamation has mainly been situated in larger general processes of population rise, commercialization and societal/technological development. The intersection of reclamation, physical environments and local economies has seldom been studied in detail. This paper conducts a local analysis of nineteenth-century wetland reclamation in two parishes in Sweden, Knätte and Mörlunda, through combining a study of specific reclamation processes with an analysis of local agrarian-economic development. The results show that these processes varied depending on specific historical-geographical circumstances. In Knätte, reclamation was not primarily related to population rise, but to increasing commercialization during the period. The case in Mörlunda instead shows how reclamation was first a response to increasing population but later developed into a project of agricultural market adaptation. In both cases, the physical environment led to varying degrees of geographic constraint in the process. In combination, these results point to the importance of detailed case studies in nuancing our understanding of nineteenth-century wetland reclamation both in Sweden and internationally. • Local factors are important for nuancing general trends in wetland reclamation. • In Sweden, population rise and commercialization are considered primary drivers. • The active drivers vary between the compared cases, depending on context. • Reclamation was primarily a part of local agrarian developments. • Wider relations of the local economy, for example through trade, also impacted. [ABSTRACT FROM AUTHOR]

Despite human geography's sophisticated analyses and overwhelming focus on space, time in its various guises has certainly not been absent in the literature. The same cannot be said for historical geography, which is particularly interesting as its main concern is purportedly with space and place in and across other times. In response, this paper examines the ontology and epistemology of time in "modern" historical geography since the early 2000s and does so in discussion with recent developments in theory and philosophy of history, specifically the notion of 'new presentism'. An idea which broadly posits that the past and the future do not exist as separate categories but are always projections of specific presents, they exist as the present's own immanent modes. This is achieved by adopting Robert Dodgshon's concept of the 'specious present' in order to (1) affirm, albeit on different epistemological grounds, the partiality, situatedness and contingency of historical geographies as well as the embodied and performative nature of archival labour; (2) offer an accessible conceptual tool in thinking about the role of time in the practice of future historical geography research; and finally (3) suggest that thinking historical geography as a practice in and through the 'specious present' makes questions of ethics, accountability, and politics of knowledge production both central and inevitable, as opposed to just being examples of "good practice" or worse still, being completely sidestepped by virtue of an imagined spatio-temporal distance between the bygone past and the present moment of research. • Examines the ontology and epistemology of time in the subdiscipline of human geography. • Provides an explanation for the field's lack of engagement with time in its investigations. • Offers a onto-epistemic framework for incorporating the specious present in historical-geographical practice. [ABSTRACT FROM AUTHOR]

Rabies is one of the oldest viral diseases and it has been present on every continent except Antarctica. Within the U.S. human rabies cases are quite rare. In the eastern USA, raccoons are the main reservoir hosts and pet vaccination serves as an important barrier against human rabies exposure. In this paper, we develop a compartmental model for rabies transmission amongst raccoons and domestic pets. We find the disease-free equilibria, reproduction numbers for the raccoons and domestic pets. We also determine the vaccination coverage/rates, both for raccoons and pets, needed to achieve the elimination of rabies. [ABSTRACT FROM AUTHOR]

[Display omitted] The key feature of living cells is multicompartmentalization for enzymatic reactions. Artificial cell-like multicompartments with micro domains are appealing to mimic the biological counterparts. In addition, establishing a sustainable, efficient, and controllable reaction system for enzymatic hydrolysis is imperative for the production of natural fatty acids from animal and plant-based fats. Reverse Janus emulsion microreactors, i.e. (W 1 + W 2)/O, is constructed through directly using natural fats as continuous phase and aqueous two-phase solutions (ATPS) as inner phases. Enzyme is confined in the compartmented aqueous droplets dominated by the salt of Na 2 SO 4 and polyethylene glycol (PEG). Enzyme catalyzed ester hydrolysis employed as a model reaction is performed under the conditions of agitation-free and mild temperature. Regulation of reaction kinetics is investigated by diverse droplet topology, composition of inner ATPS, and on-demand emulsification. Excellent enzymatic activity toward hydrolysis of plant and animal oils achieves 88.5 % conversion after 3 h. Compartmented micro domains contribute to condense and organize the enzymes spatially. Timely removal of the products away from reaction sites of oil/water interface "pushed" the reaction forward. Distribution and transfer of enzyme in two aqueous lobes provide extra freedom in the regulation of hydrolysis kinetics, with equilibrium conversion controlled freely from 14.5 % to 88.5 %. Reversible "open" and "shut" of hydrolysis is acheived by on-demand emulsification and spontaneous demulsification. This paper paves the way to advancing progress in compartmentalized emulsion as a sustainable and high-efficiency platform for biocatalytic applications. [ABSTRACT FROM AUTHOR]

The NIR-activated bacteria-killing efficiencies of chiral CuS NPs depended on the excitation light polarization and the chiral configuration enhanced photothermal efficiency. Chiral CuS NPs which adsorb on or aggregate outside the bacteria or even enter the bacteria would increase the ambient temperature quickly under NIR illumination through the photothermal effect, which leads to the inactivation of proteins of bacteria. [Display omitted] • Chiral CuS nanoparticles showed enhanced NIR-activated bacteria-killing effect compared with achiral CuS nanoparticles under the same conditions. • These chiral CuS nanoparticles showed obvious chirality-related antibacterial effect. • Photothermal bacteria-killing tests of chiral CuS NPs "sealed" in PDMS demonstrated the individual influence of photothermal effect. As the drawbacks of antibiotics in treating bacterial infections emerged, physical methods such as near-infrared-activated (NIR-activated) bacterial killing, have attracted great interests for their advantages of no resistance, short action time and few side effects. In this manuscript, NIR-activated bacteria-killing performance of chiral copper sulphide nanoparticles (L-/ d -CuS NPs) was investigated using linearly polarized light (LPL) and circularly polarized light (CPL) as illumination sources, respectively. Chiral CuS NPs showed enhanced NIR-activated bacteria-killing effect compared with achiral CuS NPs under the same conditions. Moreover, these chiral CuS NPs showed obvious chirality-related antibacterial effect: the bacterial killing was more efficient under CPL activation, and L- and d -CuS NPs had higher antibacterial efficiency under left circularly polarized light (LCPL) and right circularly polarized light (RCPL), respectively. The possible mechanism of bacteria-killing performance for chiral CuS NPs was discussed in detailed. Photothermal bacteria-killing tests of chiral CuS NPs "sealed" in polydimethylsiloxane (PDMS) demonstrated the individual influence of photothermal effect. These observations in this paper could provide ideas for the potential applications of chiral nanostructures with enhanced photothermal effect in efficient bacterial killing. [ABSTRACT FROM AUTHOR]

• This paper proposed an enet-regularization negative binomial regression model (called m6Aexpress-enet) to predict which m6A site could potentially regulate its gene expression. • m6Aexpress-enet could achieve higher prediction performance by reducing the influence of the multicollinearity problem caused by the correlation of methylation level of multiple m6A sites in each gene. • Applying m6Aexpress-enet on MeRIP-seq data from human lymphoblastoid cell lines, we have uncovered the complex regulatory pattern of predicted m6A sites and their unique enrichment pathway of the constructed co-methylation modules. As the most abundant mRNA modification, m6A controls and influences many aspects of mRNA metabolism including the mRNA stability and degradation. However, the role of specific m6A sites in regulating gene expression still remains unclear. In additional, the multicollinearity problem caused by the correlation of methylation level of multiple m6A sites in each gene could influence the prediction performance. To address the above challenges, we propose an elastic-net regularized negative binomial regression model (called m6Aexpress-enet) to predict which m6A site could potentially regulate its gene expression. Comprehensive evaluations on simulated datasets demonstrate that m6Aexpress-enet could achieve the top prediction performance. Applying m6Aexpress-enet on real MeRIP-seq data from human lymphoblastoid cell lines, we have uncovered the complex regulatory pattern of predicted m6A sites and their unique enrichment pathway of the constructed co-methylation modules. m6Aexpress-enet proves itself as a powerful tool to enable biologists to discover the mechanism of m6A regulatory gene expression. Furthermore, the source code and the step-by-step implementation of m6Aexpress-enet is freely accessed at https://github.com/tengzhangs/m6Aexpress-enet. [ABSTRACT FROM AUTHOR]

• A deep learning model for drug-target interaction prediction based on a knowledge graph and an intent graph is proposed, • Drug-target interactions be modeled from a more granular perspective, • Using relation path-aware aggregation under the GNN-base paradigm to integrate more information through a larger neighborhood region. Knowledge graph intent graph attention mechanism Predicting drug-target interactions (DTIs) plays a crucial role in drug discovery and drug development. Considering the high cost and risk of biological experiments, developing computational approaches to explore the interactions between drugs and targets can effectively reduce the time and cost of drug development. Recently, many methods have made significant progress in predicting DTIs. However, existing approaches still suffer from the high sparsity of DTI datasets and the cold start problem. In this paper, we develop a new model to predict drug-target interactions via a knowledge graph and intent graph named DTKGIN. Our method can effectively capture biological environment information for targets and drugs by mining their associated relations in the knowledge graph and considering drug-target interactions at a fine-grained level in the intent graph. DTKGIN learns the representation of drugs and targets from the knowledge graph and the intent graph. Then the probabilities of interactions between drugs and targets are obtained through the inner product of the representation of drugs and targets. Experimental results show that our proposed method outperforms other state-of-the-art methods in 10-fold cross-validation, especially in cold-start experimental settings. Furthermore, the case studies demonstrate the effectiveness of DTKGIN in predicting potential drug-target interactions. The code is available on GitHub: https://github.com/Royluoyi123/DTKGIN. [ABSTRACT FROM AUTHOR]

• An approach for pipelined event extraction consists of trigger identification, argument role recognition, and event construction. • BERT-based models are applied to three sub-tasks in biomedical event extraction. • N-ary relation extraction can effectively determine the validity of a candidate Binding event. • A pipelined biomedical event extraction rivaling joint learning. Biomedical event extraction is an information extraction task to obtain events from biomedical text, whose targets include the type, the trigger, and the respective arguments involved in an event. Traditional biomedical event extraction usually adopts a pipelined approach, which contains trigger identification, argument role recognition, and finally event construction either using specific rules or by machine learning. In this paper, we propose an n-ary relation extraction method based on the BERT pre-training model to construct Binding events, in order to capture the semantic information about an event's context and its participants. The experimental results show that our method achieves promising results on the GE11 and GE13 corpora of the BioNLP shared task with F1 scores of 63.14% and 59.40%, respectively. It demonstrates that by significantly improving the performance of Binding events, the overall performance of the pipelined event extraction approach or even exceeds those of current joint learning methods. [ABSTRACT FROM AUTHOR]