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The paper investigates the well-posedness and longtime dynamics of the Kirchhoff wave model with structural nonlinear damping: u t t − ϕ (‖ ∇ u ‖ 2) Δ u + σ (‖ ∇ u ‖ 2) (− Δ) θ u t + f (u) = g (x) , with θ ∈ [ 1 / 2 , 1). We find a new critical exponent p ⁎ ≡ N + 2 N − 2 (> p θ ≡ N + 2 θ N − 2 , N ≥ 3) and show that when the growth exponent p of the nonlinearity f (u) is up to the range: 1 ≤ p < p ⁎ : (i) the IBVP of the equation is well-posed and its solution is of additionally global regularity when t > 0 ; (ii) for each θ ∈ [ 1 / 2 , 1) , the related solution semigroup has in natural energy space H an optimal global attractor A θ whose compactness and attractiveness are in the regularized space H 1 + θ where A θ lies, and an optimal exponential attractor E θ ⁎ whose compactness, boundedness of the fractional dimension and the exponential attractiveness are in H 1 + θ where E θ ⁎ lies, respectively; (iii) the family of global attractors { A θ } θ ∈ [ 1 / 2 , 1) is upper semi-continuous at each point θ 0 ∈ [ 1 / 2 , 1). The paper breaks though the longstanding existed growth restriction: 1 ≤ p ≤ p θ for p θ had been considered a uniqueness index, deepens and extends the results in literature [6,25,27]. [ABSTRACT FROM AUTHOR]

Abstract The paper investigates longtime dynamics of the Kirchhoff wave equation with strong damping and critical nonlinearities: u t t − (1 + ϵ ‖ ∇ u ‖ 2) Δ u − Δ u t + h (u t) + g (u) = f (x) , with ϵ ∈ [ 0 , 1 ]. The well-posedness and the existence of global and exponential attractors are established, and the stability of the attractors on the perturbation parameter ϵ is proved for the IBVP of the equation provided that both nonlinearities h (s) and g (s) are of critical growth. [ABSTRACT FROM AUTHOR]

The paper investigates the stability of exponential attractors for a family of semilinear wave equations with gentle dissipation: u t t − Δ u + γ ( − Δ ) α u t + f ( u ) = g ( x ) , with α ∈ ( 0 , 1 / 2 ) . (i) We propose a new criterion on the existence and stability of a family of exponential attractors depending on the perturbation parameters. (ii) By applying this criterion to the equations, we construct a family of exponential attractors A e x p α and show their stability on the dissipative exponent α . [ABSTRACT FROM AUTHOR]

The paper investigates the existence of global attractor of the quasi-linear wave equation with strong damping u t t − γ Δ u t − Δ u + f ( u ) = ∇ ⋅ ϕ ′ ( ∇ u ) + g . It proves that the energy solution of the equation is stable and the related dynamical system possesses a (strong) global attractor in natural energy space (rather than a weak one as known before). These results improve the recent ones in [13] . [ABSTRACT FROM AUTHOR]

The paper investigates the global well-posedness and the longtime dynamics of the Kirchhoff equations with fractional damping and supercritical nonlinearity: u t t − M ( ‖ ∇ u ‖ 2 ) Δ u + ( − Δ ) α u t + f ( u ) = g ( x ) , with α ∈ ( 1 2 , 1 ) . The main results are focussed on the relationships among the growth exponent p of the nonlinearity f ( u ) , the global well-posedness and the longtime dynamics of the equations. We show that (i) even if p is up to the supercritical range, that is, 1 ≤ p < N + 4 α ( N − 4 α ) + , the well-posedness and the longtime behavior of the solutions of the equation are of the characters of the parabolic equation; (ii) when N + 4 α ( N − 4 α ) + ≤ p < N + 4 ( N − 4 ) + , the corresponding subclass G of the limit solutions exists and possesses a weak global attractor. [ABSTRACT FROM AUTHOR]

The paper studies the longtime dynamics of the Kirchhoff equation with strong damping and critical nonlinearity on R N : u t t − Δ u t − M ( ‖ ∇ u ‖ 2 ) Δ u + u t + g ( x , u ) = f ( x ) . We establish the well-posedness, the existence of the global and exponential attractors in natural energy space H = H 1 ( R N ) × L 2 ( R N ) in critical nonlinearity case. These results improve not only the recent ones achieved by Yang (2007) [32] , but also ones achieved by Conti, Pata and Squassina (2005) [9] to some extent. [ABSTRACT FROM AUTHOR]

Abstract: The paper studies the global existence, stability and the longtime dynamics of solutions to the initial boundary value problem (IBVP) of an extensible beam equation with nonlinear damping and source terms: . It proves that (i) the IBVP is global well posed provided that either the growth exponent p of the source term is non-supercritical, that is, and if or p is supercritical but is dominated by the growth exponent q of the nonlinear damping , i.e. if ; (ii) the related solution semigroup has in phase space X a finite-dimensional global attractor , which has -regularity, and also an exponential attractor provided either or if ; (iii) especially, when the space dimension , all the above mentioned conclusions hold without any restriction on p and q, that is, . [Copyright &y& Elsevier]

Abstract: The paper studies the longtime dynamics of the damped Boussinesq equation . First, the existence of global solutions to the initial boundary value problem of the equation is obtained provided that the growth exponent of , say , is either non-supercritical (subcritical and critical) or supercritical, especially, the stability of solutions is established when is non-supercritical. Second, the existence of a global attractor and an exponential attractor for the related solution semigroup are respectively established in the non-supercritical case. [Copyright &y& Elsevier]

Abstract: The paper studies the existence of the finite-dimensional global attractors and exponential attractors for the dynamical system associated with the Kirchhoff type equation with a strong dissipation . It proves that the above mentioned dynamical system possesses a global attractor which has finite fractal dimension and an exponential attractor. For application, the fact shows that for the concerned viscoelastic flow the permanent regime (global attractor) can be observed when the excitation starts from any bounded set in phase space, and the dimension of the attractor, that is, the number of degree of freedom of the turbulent phenomenon and thus the level of complexity concerning the flow, is finite. [Copyright &y& Elsevier]

Abstract: The paper studies the existence and non-existence of global weak solutions to the Cauchy problem for the multi-dimensional Boussinesq type equation . It proves that the Cauchy problem admits a global weak solution under the assumptions that , is of polynomial growth order, say p (>1), either , , where is a constant, or the initial data belong to a potential well. And the weak solution is regularized and the strong solution is unique when the space dimension . In contrast, any weak solution of the Cauchy problem blows up in finite time under certain conditions. And two examples are shown. [Copyright &y& Elsevier]

Abstract: The paper studies the longtime behavior of the Kirchhoff type equation with strong damping on . It shows that the related continuous semigroup possesses a global attractor which is connected and has finite fractal and Hausdorff dimension. [Copyright &y& Elsevier]

Abstract: The paper studies the global existence and asymptotic behavior of weak solutions to the Cauchy problem for quasi-linear wave equations with viscous damping. It proves that when , where , and are, respectively, the growth orders of the nonlinear strain terms, the nonlinear damping term and the source term, the Cauchy problem admits a global weak solution, which decays to zero according to the rate of polynomial as , as long as the initial data are taken in a certain potential well and the initial energy satisfies a bounded condition. Especially in the case of space dimension , the solutions are regularized and so generalized and classical solution both prove to be unique. Comparison of the results with previous ones shows that there exist clear boundaries similar to thresholds among the growth orders of the nonlinear terms, the states of the initial energy and the existence, asymptotic behavior and nonexistence of global solutions of the Cauchy problem. [Copyright &y& Elsevier]

Abstract: The paper studies the existence and non-existence of global weak solutions to the Cauchy problem for a class of quasi-linear wave equations with nonlinear damping and source terms. It proves that when , where , and are, respectively, the growth orders of the nonlinear strain terms, the nonlinear damping term and the source term, under rather mild conditions on initial data, the Cauchy problem admits a global weak solution. Especially in the case of space dimension , the weak solutions are regularized and so generalized and classical solution both prove to be unique. On the other hand, if , and the initial energy is negative, then under certain opposite conditions, any weak solution of the Cauchy problem blows up in finite time. And an example is shown. [Copyright &y& Elsevier]

Chemical coupling of polyethylene glycol (PEG) to therapeutic proteins reduces their immunogenicity and prolongs their circulating half-life. The limitation of this approach is the number and distribution of sites on proteins available for PEGylation (the N terminus and the #x03B5;-amino group of lysines). To increase the extent of PEGylation, we have developed a method to increase the number of PEGylation sites in a model protein, recombinant methionine α,γ-lyase (recombinant methioninase; rMETase), an enzyme cancer therapeutic cloned from Pseudomonas putida. rMETase was first PEGylated with methoxypolyethylene glycol succinimidyl glutarate-5000 with a molar ratio of PEG:rMETase of 15:1. The carboxyl groups of the initially PEGylated protein were then conjugated with diaminobutane, resulting in carboxyl amidation. This reaction was catalyzed by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide, a water-soluble carbodiimide. The steric hindrance provided by the PEG chains already coupled to the protein prevented cross-linking between rMETase molecules during the carboxyl amidation reaction. The carboxyl-amidated PEGylated rMETase was hyper-PEGylated at a molar ratio of PEG to PEG-rMETase of 60:1. Biochemical analysis indicated that 13 PEG chains were coupled to each subunit of rMETase after hyper-PEGylation compared with 6–8 PEG chains attached to the non-carboxyl-amidated PEG-rMETase. Approximately 15–20% of the non-PEGylated rMETase activity was retained in the hyper-PEGylated molecule. Immunogenicity of the hyper-PEG-rMETase was significantly reduced relative to PEG-rMETase and rMETase. Initial results suggest that hyper-PEGylation may become a new strategy for PEGylation of protein biologics. [Copyright &y& Elsevier]

In this paper, the global existence of solutions to the initial boundary value problem for a class of quasi-linear wave equations with viscous damping and source terms is studied by using a combination of Galerkin approximations, compactness, and monotonicity methods. [Copyright &y& Elsevier]

The paper studies the blowup of solutions to the initial boundary value problem for the “bad” Boussinesq-type equation utt−uxx−buxxxx=σ(u)xx, where b>0 is a real number and σ(s) is a given nonlinear function. By virtue of the energy method and the Fourier transform method, respectively, it proves that under certain assumptions on σ(s) and initial data, the generalized solutions of the above-mentioned problem blow up in finite time. And a few examples are shown, especially for the “bad” Boussinesq equation, two examples of blowup of solutions are obtained numerically. [Copyright &y& Elsevier]

The paper studies the existence and uniqueness of local solutions and the blowup of solutions to the initial boundary value problem for improved Boussinesq type equation utt−uxx−uxxtt=σ(u)xx. By a Galerkin approximation scheme combined with the continuation of solutions step by step and the Fourier transform method, it proves that under rather mild conditions on initial data, the above-mentioned problem admits a unique generalized solution u∈W2,∞([0,T];H2(0,1)) as long as σ∈C2(R). In particular, when σ(s)=asp, where a≠0 is a real number and p>1 is an integer, specially a<0 if p is an odd number, the solution blows up in finite time. Moreover, two examples of blowup are obtained numerically. [Copyright &y& Elsevier]

The paper investigates the well-posedness, regularity and longtime behavior of solutions for an extensible beam equation with fractional rotational inertia and structural nonlinear damping: (1 + (− Δ) θ) u t t + Δ 2 u − M (‖ ∇ u ‖ 2) Δ u + N (‖ ∇ u ‖ 2) (− Δ) α u t + f (u) = g , with dissipative index α ∈ (0 , 1 ] and rotational index θ ∈ [ 0 , α). We find a new critical exponent p θ α ≡ N + 2 (2 α − θ) (N − 4) + (> p ⁎ = N (N − 4) + ) depending on both θ and α and show that when the growth exponent p of the nonlinearity f (u) is up to the range: 1 ≤ p < p θ α , the well-posedness, regularity and longtime behavior of the solutions are like parabolic, in the concrete, (i) the IBVP of the equation admits a unique strong solution while its initial data is in weaker energy space; (ii) the related solution semigroup has a strong global attractor and a strong exponential attractor for each θ ∈ [ 0 , α) , where the "strong" means that the compactness, the attractiveness and the finiteness of the fractal dimension of the attractors are all in the topology of the strong solution space; (iii) the family of strong global attractors { A θ } θ ∈ [ 0 , α) is upper-semicontinuous on the perturbed index θ at any point θ 0 ∈ [ 0 , α). These results improve and extend those in recent literatures [17,24]. [ABSTRACT FROM AUTHOR]

• A review of the adoption of generative adversarial networks in clinical neuroimaging. • We focus on GAN's applications in modeling disease effects of neurologic diseases. • We discuss the pitfalls of current studies and provide future perspectives. Generative adversarial networks (GANs) are one powerful type of deep learning models that have been successfully utilized in numerous fields. They belong to the broader family of generative methods, which learn to generate realistic data with a probabilistic model by learning distributions from real samples. In the clinical context, GANs have shown enhanced capabilities in capturing spatially complex, nonlinear, and potentially subtle disease effects compared to traditional generative methods. This review critically appraises the existing literature on the applications of GANs in imaging studies of various neurological conditions, including Alzheimer's disease, brain tumors, brain aging, and multiple sclerosis. We provide an intuitive explanation of various GAN methods for each application and further discuss the main challenges, open questions, and promising future directions of leveraging GANs in neuroimaging. We aim to bridge the gap between advanced deep learning methods and neurology research by highlighting how GANs can be leveraged to support clinical decision making and contribute to a better understanding of the structural and functional patterns of brain diseases. [Display omitted] [ABSTRACT FROM AUTHOR]

MicroRNA (miRNA) is one of the most potent therapeutic targets for osteoarthritis (OA). We identified that miR-654-3p protected the phenotype of chondrocytes. We demonstrated that TNF receptor superfamily member 9 (TNFRSF9) was the target of miR-654-3p by binding to its 3′UTR regions, based on a dual-luciferase reporter assay and an RNA binding protein immunoprecipitation (RIP) assay. In addition, further experiments proved that TNFRSF9, as a trigger of the NF-κB pathway, correlated with the inflammation in chondrocytes. MiR-654-3p overexpressed in the knee of mice alleviated the OA in vivo. Moreover, we examined the m6A enzyme level in OA, proving that the abnormal expression of α-ketoglutarate-dependent dioxygenase alkB homolog 5 (ALKBH5) contributed to the miR-654-3p decrease. Our research illustrated the significant role of miR-654-3p in OA, including its maturation and the mechanism in protecting the phenotype of chondrocytes, which could be a new treatment target for OA. • miR-654-3p decreased the inflammation in OA by targeting TNFRSF9 directly. • TNFRSF9 activated the NF-κB Pathway in OA which could be suppressed by CD137 protein. • Excessive ALKBH5 limited the maturation of miR-654-3p. [ABSTRACT FROM AUTHOR]

The antimetastatic activity of a novel camptothecan conjugate, MEN4901/T-0128, in which 7-ethyl-10-aminopropyloxy-camptothecin (T-2513) is bound to a biodegradable carboxymethyldextran via a Gly-Gly-Gly linker, was observed in this study. High antimetastatic activity of MEN4901/T-0128 was demonstrated in a clinically-relevant orthotopic mouse model of human colon cancer. MEN4901/T-0128 and irinotecan were compared for anti-metastatic activity as well as efficacy against the primary tumor. An imageable, metastatic model was made by surgical orthotopic implantation (SOI) of the green fluorescent protein (GFP)-expressing HT-29 tumor in nude mice. MEN4901/T-0128 and irinotecan were administered intravenously at various doses and schedules. MEN4901/T-0128, with treatment beginning on d 49 after SOI, was highly effective on lymph node metastasis as well as against the primary tumor. Both GFP imaging and histology demonstrated a markedly lower metastatic incidence of lymph nodes in all MEN4901/T-0128 treated mice compared with irinotecan-treated and untreated mice. At the most efficacious dose of MEN4901/T-0128, only 1 of 12 animals had lymph node metastasis compared with 19 of 20 in the control group. The present study demonstrates the principle that when a camptothecan is conjugated to an appropriate polymer, the drug can become extremely effective with important clinical potential for antimetastatic therapy, a most urgent need. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases. However, the AD mechanism has not yet been fully elucidated to date, hindering the development of effective therapies. In our work, we perform a brain imaging genomics study to link genetics, single-cell gene expression data, tissue-specific gene expression data, brain imaging-derived volumetric endophenotypes, and disease diagnosis to discover potential underlying neurobiological pathways for AD. To do so, we perform brain-wide genome-wide colocalization analyses to integrate multidimensional imaging genomic biobank data. Specifically, we use (1) the individual-level imputed genotyping data and magnetic resonance imaging (MRI) data from the UK Biobank, (2) the summary statistics of the genome-wide association study (GWAS) from multiple European ancestry cohorts, and (3) the tissue-specific cis-expression quantitative trait loci (cis-eQTL) summary statistics from the GTEx project. We apply a Bayes factor colocalization framework and mediation analysis to these multi-modal imaging genomic data. As a result, we derive the brain regional level GWAS summary statistics for 145 brain regions with 482,831 single nucleotide polymorphisms (SNPs) followed by posthoc functional annotations. Our analysis yields the discovery of a potential AD causal pathway from a systems biology perspective: the SNP chr10:124165615:G>A (rs6585827) mutation upregulates the expression of BTBD16 gene in oligodendrocytes, a specialized glial cells, in the brain cortex, leading to a reduced risk of volumetric loss in the entorhinal cortex, resulting in the protective effect on AD. We substantiate our findings with multiple evidence from existing imaging, genetic and genomic studies in AD literature. Our study connects genetics, molecular and cellular signatures, regional brain morphologic endophenotypes, and AD diagnosis, providing new insights into the mechanistic understanding of the disease. Our findings can provide valuable guidance for subsequent therapeutic target identification and drug discovery in AD. [ABSTRACT FROM AUTHOR]

Abstract The impact of electron injection on vertical leakage current of GaN-on-Si epitaxial layers with an AlN interlayer has been investigated. At high electric field, the AlN interlayer as an energy barrier can suppress the injection of electrons from the silicon substrate into the top buffer layers, and eventually a vertical leakage was reduced by two orders of magnitude at 600 V. At low electric field, the holes flow via dislocations, and prevent the formation of a negative depletion region at the top GaN layer increasing the leakage. The correlation between the vertical leakage and the buffer-related trapping has also been clarified by ramped back-gating characterizations. Highlights • The vertical leakage was reduced by two orders of magnitude at 600 V with an AlN interlayer. • At high electric field, the results indicate that the electron injection plays a key role on vertical leakage. • At low field, the hole flowing via dislocations could increase the leakage for sample with an AlN interlayer. • The buffer related trapping effect is suppressed by inserting an AlN interlayer. [ABSTRACT FROM AUTHOR]

In recent years a class of vibrating plates with nonlinear strain of p -Laplacian type was studied by several authors. The present paper contains a first thermoelastic model of that class of problems including both Fourier and non-Fourier heat laws. Our main result establishes the existence of global and exponential attractors for the strongly damped problem through a stabilizability inequality. In addition, for the weakly damped problem, we establish the exponential stability of its Galerkin semiflows. [ABSTRACT FROM AUTHOR]

It is well recognized that the incidence of heart failure and the risk of death is high in diabetic patients after myocardial infarction (MI). Accumulating evidence showed that puerarin (PUE) has protecting function on both cardiovascular disease and diabetes. The aim of this study is to explore whether puerarin could improve cardiac function in diabetic mice after MI and the underlying mechanism. The left anterior of Streptozotocin (STZ)-Nicotinamide (NA) induced diabetic mice were ligated permanently except for the Shame group. Then the operated mice were randomly treated with PUE or saline. Cardiac function was evaluated by echocardiograph before and at 1, 2, 4 weeks after MI. GLUT4/CD36/p-Akt/PPAR α of the heart was examined after treatment for 4 weeks. The results indicated that PUE significantly increased survival rate, improved cardiac function compared with MI group. Moreover, PUE increased expression and translocation of GLUT4 while attenuated expression and translocation of CD36. Western blot analysis showed that PUE enhanced phosphorylation of Akt and decreased PPAR α. This study demonstrated that PUE improved cardiac function after MI in diabetic mice through regulation of energy metabolism, the possible mechanism responsible for the effect of PUE was increasing the expression and translocation of GLUT4 while attenuating the expression and translocation of CD36. [ABSTRACT FROM AUTHOR]

Paleolithic rock paintings are known from many parts of the world, including Africa, Australia, Europe and Island Southeast Asia. However, no Paleolithic rock paintings have yet been confirmed in the East Asia mainland, partly due to the lack of suitable dating materials. The rock paintings distributed at more than 70 sites in the Jinsha River valley, Yunnan Province, southwestern China, include the naturalistic outlines of large mammals, which superficially resemble the Magdalenian rock art in Europe. Wanrendong Cave in Tiger Leaping Gorge, has preserved typical Jinsha River rock paintings, associated with some precipitates of secondary carbonates (i.e., speleothem). High precision U-series dating of 13 small speleothems, with a total of 36 subsamples overlying or underlying the pigment layers, revealed that these red paintings were created during the Pleistocene – Holocene transition, representing the oldest absolutely dated rock paintings from China so far. Our results show that at least three painting phases in Wanrendong Cave can be precisely constrained: ∼13,000–13,580 yr B.P., ∼10,540–10,830 yr B.P., and ∼8370–8700 yr B.P. These intervals are substantially earlier than the timing of agriculture in Yunnan Province (∼4600 yr BP), indicating that these paintings were created by Paleolithic hunter-gatherers. Additionally, these intervals coincide with the Bølling-Allerød and early Holocene warming periods, suggesting a possible link between the rock painting activity and climate changes. • High-precision U-series dating was applied to the speleothems associated with the rock paintings in Wanrendong Cave. • Wanrendong rock paintings were dated to three phases: 1) ∼13,000–13,580 yr B.P., 2) ∼10,540–10,830 yr B.P., and 3) ∼8370–8700 yr B.P. • The ages of Wanrendong rock paintings indicate that these paintings were created by Paleolithic hunter-gatherers. [ABSTRACT FROM AUTHOR]

Spontaneously self-organized growth of core-shell GaN/GaN:Mn micro-wires were obtained by metalorganic chemical vapor deposition (MOCVD) without catalyst. The structure and magnetic properties of single core-shell GaN/GaN:Mn micro-wire were investigated. Mn atoms substituted for the Ga atoms without microprecipitates or clusters in the GaN:Mn shell layer. The magnetic hysteresis curve showed that the core-shell GaN/GaN:Mn micro-wires were ferromagnetic above room temperature. In addition, a single ferromagnetic domain was confirmed by magnetic force microscope (MFM) in the as-grown GaN:Mn shell layer without external magnetic field applied before, excluding secondary phases in GaN:Mn. • Spontaneously self-organized growth of core-shell GaN/GaN:Mn micro-wires were obtained by metalorganic chemical vapor deposition (MOCVD) without catalyst. • Mn atoms substituted for the Ga atoms without microprecipitates or clusters in the GaN:Mn shell layer. • The magnetic hysteresis curve showed that the core-shell GaN/GaN:Mn micro-wires were ferromagnetic above room temperature. • A single ferromagnetic domain was confirmed by magnetic force microscope (MFM) in the as-grown GaN:Mn shell layer without external magnetic field applied before, excluding secondary phases in GaN:Mn. [ABSTRACT FROM AUTHOR]