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Objective Damage associated molecular patterns (DAMPs) are pathological mediators linking local tissue damage to systemic inflammation in various diseases. Some DAMPs, such as mitochondrial DNA (mtDNA), can be recognized by the cytoplasmic cGAS protein to trigger the activation of the stimulator of interferon genes (STING)-dependent innate immune pathway responsible for infection or sterile inflammation. The objective of our study was to evaluate the association between circulating mtDNA and cGAS-STING pathway activation in mediating inflammation following burn injury. Methods 48 adult Sprague-Dawley male rats were divided into eight groups (Sham, 2, 4, 8, 12, 24, 48, 72 h after burn injury). The animals underwent 40% total body surface area scald injury to produce a full-thickness burn. Plasma samples were collected via cardiac puncture under deep anesthesia. Tissues were harvested and placed in formalin, followed by paraffin embedment. Total plasma DNA was isolated followed by measurement of mtDNA using quantitative polymerase chain reaction. Haemotoxylin-Eosin stain and Western blot was used for lung histology and protein assays, respectively. Statistical analyses were performed using ANOVA and student’s t-test and represented as mean ± s.d. Results Plasma mtDNA trended upward at early time-points following burn injury with peak levels at 8 h after burn when compared to the control group (345 ± 83.4 copies/μl vs. 239 ± 43.1 copies/μl, p = 0.07) and followed a bell-shaped distribution. Lung slices from burned rats showed acute injury marked by increased inflammatory infiltrate, with the maximum changes seen at 24 h, accompanied with significant upregulation of neutrophil elastase (p = 0.04). Compared with sham animals, cGAS and STING protein levels in lung tissue were up-regulated at 4 and 8 h after burn (p = 0.03 and p Conclusion Activation of the cGAS-STING pathway by increased plasma mtDNA is an important pathway driving neutrophil infiltration in burn-induced acute lung injury in rats. A further understanding of the STING-mediated immunopathology in lung and other susceptible organs may be important for the development of novel therapies for burn injury.

This paper is concerned with a class of nonlocal reaction-diffusion equations with time-delay and degenerate diffusion. Affected by the degeneracy of diffusion, it is proved that, the Cauchy problem of the equation possesses the Holder-continuous solution. Furthermore, the non-critical traveling waves are proved to be globally L 1 -stable, which is the first frame work on L 1 -wavefront-stability for the degenerate diffusion equations. The time-exponential convergence rate is also derived. The adopted approach for the proof is the technical L 1 -weighted energy estimates combining the compactness analysis, but with some new development.

The initial value problems of bipolar isentropic/non-isentropic compressible Navier-Stokes-Maxwell (CNS-M) systems arising from plasmas in R 3 are studied. The main difficulty of studying the bipolar isentropic/non-isentropic CNS-M systems lies in the appearance of the electromagnetic fields satisfying the hyperbolic Maxwell equations. The large time-decay rates of global smooth solutions with small amplitude in L q ( R 3 ) for 2 ≤ q ≤ ∞ are established. For the bipolar non-isentropic CNS-M system, the difference of velocities of two charged carriers decay at the rate ( 1 + t ) − 3 4 + 1 4 q which is faster than the rate ( 1 + t ) − 3 4 + 1 4 q ( ln ⁡ ( 3 + t ) ) 1 − 2 q of the bipolar isentropic CNS-M system, meanwhile, the magnetic field decay at the rate ( 1 + t ) − 3 4 + 3 4 q ( ln ⁡ ( 3 + t ) ) 1 − 2 q which is slower than the rate ( 1 + t ) − 3 4 + 3 4 q for the bipolar isentropic CNS-M system. The approach adopted is the classical energy method but with some new developments, where the techniques of choosing symmetrizers and the spectrum analysis on the linearized homogeneous system play the crucial roles.

The existence of stationary subsonic solutions and their stability for 3-D hydrodynamic model of unipolar semiconductors with the Ohmic contact boundary have been open for long time due to some technical reason, as we know. In this paper, we consider 3-D radial solutions to the system in a hollow ball, and prove that the 3-D radial subsonic stationary solutions uniquely exist and are asymptotically stable, when the initial perturbations around the subsonic steady-state are small enough. Different from the existing studies on the radial solutions for fluid dynamics where the inner boundary of the hollow ball must be far away from the singular origin, here we may allow the chosen inner boundary arbitrarily close to the singular origin and reveal the relationship between the inner boundary and the large time behavior of the radial solution. This partially answers the open question of the stability of stationary waves subjected to the Ohmic contact boundary conditions in the multiple dimensional space. We also prove the existence of non-flat stationary subsonic solution, which essentially improve and develop the previous studies in this subject. The proof is based on the technical energy estimates in certain weighted Sobolev spaces, where the weight functions are artfully selected to be the distance of the targeted spatial location and the singular point.

We consider a population dynamics model with degenerate diffusion and time delay. We discover sharp-oscillatory waves with sharp edges and non-decaying oscillations arising from density-dependent dispersal and reproduction with age structure. Degenerate diffusion and bad effect of time delay prevent the use of existing approaches. Here, we develop a new delayed iteration framework to show the existence of these peculiar waves. In particular, the estimate of the admissible wave speed is highly nontrivial. We employ a new phase transform method coupled with the detailed analysis of phase energy. Furthermore, we give a complete characterization of the dynamical behaviors of various kinds of waves. Our results indicate that simple invasion rules can generate complex wave patterns and provide some interesting insights into the ecological dynamics.

As shown in [17] , [18] , for the hydrodynamic model of semiconductors represented by Euler-Poisson equations with sonic boundary and subsonic/supersonic doping profile, the structure of stationary solutions are very complicated. It may possess various solutions like subsonic/supersonic/transonic flows. In this paper, we consider a more challenging case where the doping profile is transonic, which is categorized into two types: subsonic-dominated and supersonic-dominated. In the subsonic-dominated case, we show that the system has a unique interior subsonic solution, at least one interior supersonic solution and infinitely many transonic solutions under the suitable assumptions. However, the difference with the case of subsonic doping profile is that the interior subsonic solution and interior supersonic solution may not exist in special cases when the relaxation time is small. In the supersonic-dominated case, the non-existence and existence of all types of solutions are also obtained. The approach adopted is the technical compactness analysis combining the Green's function method. Here, the results obtained perfectly develop the existing studies.

The compaction behavior of the 3D stitched fabric, which significantly affects the mechanical performance of the 3D stitched composites, has not been explored yet. Herein, the systematical compaction experiments were originally conducted to explore the influence of the stitching pattern and space on the compaction behavior of 3D stitched carbon fabric. The results reveal that the reduction of stitching space enhances the compression resistance, as the stitching thread restricts the yarn flattening and slippage. The diagonal stitched fabric presents the high compression resistance due to its relative uniformly distributed constraining forces acted on both warp and weft yarns. It is originally identified that the internal stress in the diagonal stitched fabric is more difficult to dissipate, since the stitching thread restricts the fibers movement. Besides, the diagonal stitched fabric with dense stitching space presents high permanent recovery ratio, suggesting that the near net shape perform can be more flexibly obtained.

This paper deals with the Cauchy problem for the compressible Euler equations with time-dependent damping, where the time-vanishing damping in the form of μ ( 1 + t ) λ makes some fantastic variety of the dynamic system. For 0 λ 1 and μ > 0 , or λ = 1 but μ > 2 , the solutions are proved to exist globally in time, when the derivatives of the initial data are small, but the initial data themselves can be arbitrarily large. This is the so-called challenging case of global solutions with large initial data; while, when the initial Riemann invariants are monotonic and their derivatives with absolute value are large at least at one point, then the solutions are still bounded, but their derivatives will blow up at finite time, somewhat like the singularity formed by shock waves. For λ > 1 and μ > 0 , or λ = 1 but 0 μ ≤ 1 , the derivatives of solutions will blow up even for all initial data, including the interesting case of blow-up solutions with small initial data. Here the initial Riemann invariants are monotonic. In fact, such a blow-up phenomenon is determined by the mechanism of the dynamic system itself. In order to prove the global existence of solutions with large initial data, we introduce a new energy functional related to the Riemann invariants, which crucially enables us to build up the maximum principle for the corresponding Riemann invariants, and the uniform boundedness for the local solutions. Finally, numerical simulations in different cases are carried out, which further confirm our theoretical results.

We investigate the propagating profiles of a degenerate chemotaxis model describing the bacteria chemotaxis and consumption of oxygen by aerobic bacteria, in particular, the effect of the initial attractant distribution on bacterial clustering. We prove that the compact support of solutions may shrink if the signal concentration satisfies a special structure, and show the finite speed propagating property without assuming the special structure on attractant concentration, and obtain an explicit formula of the population spreading speed in terms of model parameters. The presented results suggest that bacterial cluster formation can be affected by chemotactic attractants and density-dependent dispersal.

Hybrid bonded-riveted joint was designed for connecting CFRP and aluminum lightweight materials used for automotive structures. The mechanical performance of hybrid joints under a wide range of temperatures from -30 to 100 °C was extensively investigated. Differential scanning calorimetry (DSC) analysis was firstly applied to determine the glass transition temperature (Tg) of polyurethane adhesive and CFRP materials, as Tg value is very important for further understanding the effect of testing temperature on mechanical behavior of hybrid joints. Digital image correlation (DIC) technique was employed to analyze progressive failure process and full-field strain distribution of hybrid joints under tensile loading. Results showed that load-displacement curve profiles, crack propagation process, mechanical properties and failure mechanisms were highly related to the type of substrate material and testing temperature. Hybrid joint exhibited maximum strength degradation of 26% and 43% under -30 and 100 °C respectively compared to the performance recorded at room temperature, while it increased up to 8% at 60 °C. Failure mechanisms including cohesive failure, adhesive failure, bearing failure of CFRP together with shear fracture of rivet were observed for hybrid joints, and they are also highly related to substrate material and testing temperature.

Current reported works of preforming behaviors mainly focus on the fabrics without binder and under constant process parameters. By contrast, in this work, preforming experiments and analysis were systematically conducted for typical carbon fiber fabrics to explore the influences of binder contents and process parameters on the preforming behaviors. We clearly reveal that the binder content has remarkable influence on the preforming behaviors. Specifically, the increasing binder content will significantly enlarge the initial thickness and the compression distance and time. Besides, it is demonstrated that the relaxation ability is also enhanced with the adding binder. The binder can also lower the elastic recovery, and oppositely increase the viscoelastic recovery, leading remarkable increment of permanent deformation. It is found that the binder should not be unlimitedly added, since over adding binder can not pronouncedly enhance the relaxation rate, and the content of 4 wt % is a relative optimal value for preforming process. We further reveal that the compression thickness can be reduced by lowering the compression speed. This approach will oppositely raise the preforming time. Thus, the compression speed should be carefully selected with the comprehensive consideration of both desired volume fraction and efficient. For the carbon fiber fabrics both with and without binder, the recovery thickness increases with the increasing maximum pressure. Besides, as the holding time increases, the permanent recovery ratio is also remarkably raised. The results obtained here provide systematical process reference to the preforming process of the fabrics with binder.

In this paper, we study the one-dimensional Euler–Poisson equations of bipolar hydrodynamic model for semiconductor device with time-dependent damping effect − J ( 1 + t ) λ for − 1 λ 1 , where the damping effect is time-gradually-degenerate for λ > 0 , and time-gradually-enhancing for λ 0 . Such a damping effect makes the hydrodynamic system possess the nonlinear diffusion phenomena time-asymptotic-weakly or strongly. Based on technical observation, and by using the time-weighted energy method, where the weights are artfully chosen, we prove that the system admits a unique global smooth solution, which time-asymptotically converges to the corresponding diffusion wave, when the initial perturbation around the diffusion wave is small enough. The convergence rates are specified in the algebraic forms O ( t − 3 4 ( 1 + λ ) ) and O ( t − ( 1 − λ ) ) according to different values of λ in ( − 1 , 1 7 ) and ( 1 7 , 1 ) , respectively, where λ = 1 7 is the critical point, and the convergence rate at the critical point is O ( t − 6 7 ln ⁡ t ) . All these convergence rates obtained in different cases are optimal in the sense when the initial perturbations are L 2 -integrable. Particularly, when λ = 1 7 , the convergence rate is the fastest, namely, the asymptotic profile of the original system at the critical point is the best.

Prenatal alcohol exposure (PAE) could lead to developmental disorders of the central nervous system (CNS) and mental retardation. Toll-like receptor (TLR) 4 plays an important role in PAE-induced neurodevelopmental defects. However, how PAE affects TLR4 response in the brain remains controversial. Using a moderate PAE model by feeding pregnant rats with liquid ethanol diet, we investigated the TLR4-mediated response to intraventricular injection of lipopolysaccharide (LPS) in the hippocampus of PEA rats at postnatal day (PND) 30. The results showed that PAE significantly up-regulated the expression of Toll-Interleukin-1 Receptor (TIR)-domain-containing adaptor protein inducing interferon (IFN)-β (TRIF), TNF-α, and IL-1β in the rat hippocampus in the absence of LPS, indicated by western blot assay. LPS treatment dramatically up-regulated the expressions of TLR4 and its downstream molecules in the hippocampus of paired-food and control groups. But no such significant changes of those molecules were found in the hippocampus of PAE animals. Moreover, the LPS stimulation even down-regulated the levels of TLR4 and TRIF in the PAE group. These data suggest that the relatively moderate level of PAE may lead to a mild neuroinflammation and a suppression of TLR4-mediated response to LPS in the hippocampus of young rats. As innate immunity plays crucial roles in CNS development, moderate PAE-induced suppression of TLR4-mediated response may serve as a new candidate mechanism of CNS developmental defects.

The preforming process of fiber fabrics in liquid composite molding presents remarkable viscoelastic behaviors, and gives significant effect on the overall mechanical properties of composite components. Thus, here, a unified viscoelastic model to predict the compression and relaxation viscoelastic behaviors in preforming process for the carbon fiber fabrics with binder is originally proposed. The physical meaning of each model parameter is rationally defined. Experiments for typical carbon fiber fabrics are conducted to validate the proposed model. The theoretical curves match well with the experimental measurements, and the correlation factors for different contents of binder are larger than 0.9, demonstrating the proposed model can well capture the stress evolution. Besides, we clearly reveal that in compression, the elastic stress is the main stress, and the viscoelastic stress is very small. Elastic modulus increases non-linearly and rapidly with the loading time. As the content of the binder increases, the elastic modulus gradually decreases due to the binder layer. For the relaxation stage, the total stress relaxation ratio is enlarged, while the elastic stress relaxation ratio is reduced, indicating the addition of binder can significantly improve the relaxation ability of the fabrics. The relationship of delay time τ : τ 0 w t τ 4 w t τ 8 w t τ 12 w t is experimentally confirmed, and is consistent with the theoretical prediction, suggesting the increasing binder enlarges the relaxation time. The proposed theoretical model here provides an approach to understand the viscoelastic responses in preforming process.

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths worldwide. Current therapies present significant limitations. Triptolide (TP) is highly effective against multiple cancers including HCC. However, high toxicity, low water solubility, and unknown therapeutic targets limit its clinical application. Herein, we designed galactosylated-chitosan-TP-nanoparticles (GC-TP-NPs) with high drug loading capacities for targeted delivery to HCC. In addition to a sustained release pattern, an efficient asialoglycoprotein receptor mediated cellular uptake in vitro, and high liver tumor accumulation in vivo, GC-TP-NPs showed lower systemic and male reproductive toxicities than free TP. Importantly, GC-TP-NPs retained the anti-cancer activities of the free TP, exerting the same pro-apoptotic and anti-proliferative effects on HCC cells in vitro, and displayed higher efficacies in reducing tumor sizes in vivo. Further investigation revealed that GC-TP-NPs induced cancer cell apoptosis via blocking TNF/NF-κB/BCL2 signaling. Collectively, GC-TP-NP represents a promising candidate in halting liver cancer progression while minimizing systemic toxicity.

In this paper, we prove the existence, uniqueness and regularity of global solution to the bistable reaction–diffusion equation with degenerate diffusion and nonlocal time-delay. The adopted approach is the Holmgren’s approximation scheme combining the compactness analysis.

This paper is concerned with time-delayed reaction–diffusion equations with degenerate diffusion. When the term for birth rate is a nonlocal integral with a heat kernel, the family of minimum wave speeds corresponding to all the degenerate diffusion coefficients is proved to admit a uniform positive infimum. However, when the term for birth rate is local, there is no positive infimum of all the minimum wave speeds. This difference indicates that the nonlocal effect plays a role as Laplacian such that a positive lower bound independent of the degenerate diffusion exists for the minimum wave speeds. The approach adopted for the proof is the monotone technique with the viscosity vanishing method. The degeneracy of diffusion for the equation causes us essential difficulty in the proof. A number of numerical simulations are also carried out at the end of the paper, which further numerically confirm our theoretical results.

The stitching pattern and space play important roles in the mechanical behaviour of stitched composites, while their effects on interlaminar shear behaviour and corresponding damage suppression mechanism have not been studied. Here, the short beam shear (SBS) test and X-ray computed tomography (XCT) were systematically performed to explore the influences of different stitching patterns and spaces on the interlaminar shear behaviour and damage suppression mechanism of stitched composites. The SBS test results reveal that a reduction in the stitching space improves the interlaminar shear performance. Especially, when the stitching patterns enable the stitch thread to bind the load-bearing yarns, the final SBS load is increased after reaching the elastic limit. Furthermore, the XCT results identify the suppression mechanism. That is, the enclosed loops formed by the stitch thread separate the fabrics into several cells. Damage propagation is interrupted within the cells in the cross-sections containing the stitch thread. Damage propagation is also suppressed in the cross-sections parallel or perpendicular to the stitch thread. Stitched composites exhibit a lower damage extension and damaged volume than unstitched composites. In particular, when the stitching pattern is perpendicular to the damage propagation direction, the damage extension is significantly reduced and depends on the stitching space. The results obtained in this study can contribute to the mechanical performance design of stitched composites in future engineering applications through purposeful modulation of the stitching pattern and space.

The purpose of this paper is to study the multi-dimensional steady hydrodynamic model of semiconductors represented by Euler-Poisson equations with sonic boundary. We prove that, the steady Euler-Poisson equations with sonic boundary possess a unique subsonic solution and at least one supersonic solution in the radial form. The adopted approach for proof is the energy method combining the compactness analysis. For the n-D radial supersonic solutions, since it is more challenging to get the crucial energy estimates due to the effect by the multiple dimensions and the restriction by the sonic boundary, we propose a brand new two-steps iteration scheme to build up the key energy estimates. This is the first attempt to study the n-D steady-states with the sonic boundary, and the results obtained essentially improve and develop the previous studies in the one-dimensional case.

In this paper, we study the Cauchy problem for the hyperbolic p-system with time-gradually-degenerate damping term − 1 ( 1 + t ) λ u for 0 ⩽ λ 1 , and show that the damped p-system has a couple of global solutions uniquely, and such solutions tend time-asymptotically to the shifted nonlinear diffusion waves, which are the solutions of the corresponding nonlinear parabolic equation governed by the Darcy's law. We further derive the convergence rates when the initial perturbations are in L 2 . The approach adopted is the technical time-weighted energy method.

In this paper we study the hybrid quantum hydrodynamic model for nano-sized bipolar semiconductor devices in thermal equilibrium. By introducing a hybrid version of the Bhom potential, we derive a bipolar hybrid quantum hydrodynamic model, which is able to account for quantum effects in a localized region of the device for both electrons and holes. Coupled with Poisson equation for the electric potential, the steady-state system is regionally degenerate in its ellipticity, due to the quantum effect only in part of the device. This regional degeneracy of ellipticity makes the study more challenging. The main purpose of the paper is to investigate the existence and uniqueness of the weak solutions to this new type of equations. We first establish the uniform boundedness of the smooth solutions to the modified bipolar quantum hydrodynamic model by the variational method, then we use the compactness technique to prove the existence of weak solutions to the original hybrid system by taking hybrid limit. In particular, we account for two different kinds of hybrid behaviour. We perform the first hybrid limit when both electrons and holes behave quantum in a given region of the device, and the second one when only one carrier exhibits hybrid behaviour, whereas the other one is presented classically in the whole domain. The semi-classical limit results are also obtained. Finally, the theoretical results are tested numerically on a simple toy model.

The relaxation limit from bipolar semiconductor hydrodynamic (HD) model to drift–diffusion (DD) model is shown under the non-constant doping profile assumption for both stationary solutions and global-in-time solutions, which satisfy the general form of the Ohmic contact boundary condition. The initial layer phenomenon will be analyzed because the initial data is not necessarily in the momentum equilibrium. Due to the bipolar coupling structure, the analysis is hard and different from the previous literature on unipolar model or bipolar model with zero doping profile restriction. We first construct the non-constant uniform stationary solutions by the operator method for both HD and DD models in a unified procedure. Then we prove the global existence of DD model and uniform global existence of HD model by the elementary energy method but with some new developments. Based on the above existence results, we further calculate the convergence rates in relaxation limits.