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This paper is concerned with the critical sharp traveling wave for doubly nonlinear diffusion equation with time delay, where the doubly nonlinear degenerate diffusion is defined by $\Big(\big|(u^m)_x\big|^{p-2}(u^m)_x\Big)_x$ with $m>0$ and $p>1$. The doubly nonlinear diffusion equation is proved to admit a unique sharp type traveling wave for the degenerate case $m(p-1)>1$, the so-called slow-diffusion case. This sharp traveling wave associated with the minimal wave speed $c^*(m,p,r)$ is monotonically increasing, where the minimal wave speed satisfies $c^*(m,p,r)0$. The sharp front is $C^1$-smooth for $\frac{1}{p-1}, Comment: arXiv admin note: text overlap with arXiv:1909.11751

ObjectivesCutaneous tuberculosis with various manifestations can be divided into several clinical types according to the host's immune status and infective route. However, the etiological factors of this disease remain unclear. The objective of this study is to investigate the pathogens associated with the occurrence and different types of cutaneous tuberculosis.Methods58 Mycobacterium tuberculosis strains isolated from cutaneous tuberculosis over the last 20 years were sequenced and analyzed for genomic characteristics including lineage distribution, drug-resistance mutations, and mutations potentially associated with different sites of infection.ResultsThe M. tuberculosis strains from four major types of cutaneous tuberculosis and pulmonary tuberculosis shared similar genotypes and genomic composition. The strains isolated from cutaneous tuberculosis had a lower rate of drug resistance. Phylogenic analysis showed cutaneous tuberculosis and pulmonary tuberculosis isolates scattered on the three. Several SNPs in metabolism related genes exhibited a strong correlation with different infection sites.ConclusionsThe different infection sites of TB may barely be affected by large genomic changes in M. tuberculosis isolates, but the significant difference in SNPs of drug resistance gene and metabolism-related genes still deserves more attention.

The compounds composed of transition meatal cations and pnictide anions provide a rich platform for novel physical phenomena. Here we report the observation of a phase transition at ~ 70 K and 145 K from both the transport and heat capacity in layered compound EuCu4As2 and SrCu4As2, respectively. The thermal expansion measurements present that the variations of the lattice parameters (ΔLab /Lab ) around TP , are significantly less than that for a typical crystalline phase transition. Our experimental results reveal that transition in EuCu4As2 and SrCu4As2 should be driven by subtle structural-distortion.

We present the synthesis of TaCoTe2 single crystals and systematical investigation of the physical properties of bulk crystals and thin flakes. The crystal shows a semiconducting behavior with temperature decreasing from room temperature and turn to a metallic behavior below 38 K. When magnetic field is applied, the temperature-dependent resistivity curves show an upturn below 10 K. Furthermore, we found that the TaCoTe2 single crystal can be easily exfoliated from the bulk crystal by micro-mechanical exfoliation method. Our measurements suggest that the nanoflakes have similar properties with the bulk crystal when the thickness is lowered to 18 nm.

Adding adipose cells to cell-cultured meat can provide a distinctive aroma and juicy texture similar to real meat. However, a significant challenge still exists in obtaining seed cells that can be propagated for long periods, maintain their adipogenic potential, and reduce production costs. In this study, we present a cell strain derived from immortalized porcine preadipocytes that can be subculture for over 40 passages without losing differentiation capacity. This cell strain can be differentiated within 3D bioscaffolds to generate cell-cultured fat using fewer chemicals and less serum. Additionally, it can be expanded and differentiated on microcarriers with upscaled culture to reduce costs and labor. Moreover, it can co-differentiate with muscle precursor cells, producing a marbling pattern. Therefore, our cell strain provides an exceptional model for studying and producing cell-cultured fat.

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.

Background: Ventilator-associated pneumonia (VAP) is a significant and common health concern, and epidemiological landscape of VAP is poorly understood in neurosurgery. The current study aimed to explore the epidemiology of VAP in neurosurgery with the goal of devising better-targeted surveillance, treatment and control efforts. Methods: A ten-year retrospective study was performed in a large Chinese tertiary hospital, and we collected surveillance data on neurosurgical patients with VAP and used descriptive analysis to map the demographic and clinical characteristics of VAP as well as the distribution and antimicrobial resistance profile of leading pathogens. Risk factors associated with the presence of VAP were explored using boosted regression tree (BRT) models. Results: During 2011-2020, a total of 310 VAP patients were identified. The ten-year incidence of VAP was 16.21 per 1000 ventilation days with all-cause mortality rate of 6.1%. The proportions of gram-negative bacteria, fungi and gram-positive bacteria in 357 isolates from 310 VAP patients were 86.0%, 7.6% and 6.4%, and most of them were multidrug-resistant organisms. Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa were the most common pathogens causing VAP, and high detection rates of CRAB, CRPA and CRKP with an upward trend were observed. The BRT modes revealed that there were various associations of VAP presence with the days of ventilator use (relative contribution: 47.84 ± 7.25), GCS score (relative contribution: 24.72 ± 5.67), and tracheotomy (relative contribution: 21.50 ± 2.69), respectively. Conclusions: Our findings provide a better understanding of epidemiological characteristics and risk factors for VAP in neurosurgery.

This paper is concerned with the Cauchy problem for one-dimensional unipolar Euler-Poisson equations with time-dependent damping, where the time-asymptotically degenerate damping in the form of − μ/(1+t)λ ρu for λ > 0 with μ > 0 plays a crucial role for the structure of solutions. The main issue of the paper is to investigate the critical case with λ = 1. We first prove that, for all cases with λ > 0 and μ > 0 (including the critical case of λ = 1), once the initial data is steep at a point, then the solutions are locally bounded but their derivatives will blow up in finite time, by means of the method of Riemann invariants and the technical convex analysis. Secondly, for the critical case of λ = 1 with μ > 7/3, we prove that there exists a unique global solution, once the initial perturbation around the constant steady-state is sufficiently small. In particular, we derive the algebraic convergence rates of the solution to the constant steady-state, which are piecewise, related to the parameter μ for 7/3 < μ ≤ 3, 3 < μ ≤ 4 and μ > 4. The adopted method of proof in this critical case is the technical time-weighted energy method and the time-weight depends on the parameter μ. Finally, we carry out some numerical simulations in two cases for blow-up and global existence, respectively, which numerically confirm our theoretical results.

In this work, effective thermal conductivity (λEff) of fractured rock masses was numerically investigated. A two-dimensional Discrete Fracture Network (DFN) model of the fractured rock masses was established based on the statistic results of natural fracture development in a potential area for high level radioactive waste disposal in China. Steady state heat transfer processes in the fractured granite rock masses were numerically simulated using finite element method (FEM). The calculated λEff values of the fractured granite rock masses in dry and saturated conditions are 1.99 W/(m K) and 2.31 W/(m K), respectively. Compared with the thermal conductivity of intact granite [λIntact, 2.5 W/(m K)], the drop rates are 20.4% and 7.6%, respectively. Sensitivity analysis was conducted on the main model parameters including fracture density (FDensity), trace length (FLength), thermal contact resistance (FTCR), and λIntact. The results indicate the relation between λEff and three fracture parameters (FDensity, Flength and FTCR) can be fitted using power law or negative exponent functions with good consistency. When fracture network parameters remain unchanged, λEff is in linear positive correlation to λIntact. The slop of the fitted line is determined by the fracture network parameters. Due to the fact that distribution of generated fractures in different directions are quite uniform, λEff did not show significant difference in different directions. On the basis of the above-mentioned results, an estimation model was proposed for the determination of λEff of fractured rock masses using P21 (total length of fracture traces per unit area), FTCR, and λIntact. The proposed estimation model shows good consistency to the calculated results of FEM model.

Si-Yu Long,1 Le Wang,1,2 Hai-Qin Jiang,1 Ying Shi,1 Wen-Yue Zhang,1 Jing-Shu Xiong,1 Pei-Wen Sun,1,2 Yan-Qing Chen,1 You-Ming Mei,1 Chun Pan,1 Gai Ge,1 Zhen-Zhen Wang,1 Zi-Wei Wu,1 Mei-Wen Yu,1,2 Hong-Sheng Wang1– 3 1Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, 210042, People’s Republic of China; 2National Centre for Leprosy Control, China CDC, Nanjing, People’s Republic of China; 3Centre for Global Health, School of Public Health, Nanjing Medical University, Nanjing, People’s Republic of ChinaCorrespondence: Hong-Sheng Wang; Mei-Wen YuJiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, St 12 Jiangwangmiao, Nanjing, Jiangsu, 210042, People’s Republic of ChinaEmail whs33@vip.sina.com; yumeiwen@163.comBackground: Genome-wide association studies (GWASs) have identified some immune-related single-nucleotide polymorphisms (SNPs) to be associated with leprosy.Methods: This study investigated the association of 17 SNPs based on previously published GWAS studies with susceptibility to leprosy, different polar forms and immune states of leprosy in a case–control study from southwestern China, including 1344 leprosy patients and 2732 household contacts (HHCs) (1908 relatives and 824 genetically unrelated contact individuals). The differences of allele distributions were analyzed using chi-squared analysis and logistic regression.Results: After adjusting covariate factors, rs780668 and rs3764147 polymorphisms influenced susceptibilities to genetically related or unrelated leprosy contact individuals. rs142179458 was associated with onset early cases, rs73058713 A allele and rs3764147 A allele increased the risk of reversal reaction, while rs3764147 G allele had higher risk to present lepromatous leprosy and erythema nodosum leprosum.Conclusion: Our results demonstrated that genetic variants in the LACC1, HIF1A, SLC29A3 and CDH18 genes were positively correlated with the occurrence of leprosy and leprosy clinical phenotypes, providing new insights into the immunogenetics of the disease.Keywords: leprosy, association study, susceptibility gene, polymorphisms

The autonomous vehicle has been developed widely, and attracted much attention of global automotive industry. Wherein, longitudinal dynamics control is one of the most crucial issues of autonomous vehicles. The throttle-by-wire (TBW) control could implement the acceleration command through adjusting the throttle opening, thus control the driving torque of the fuel autonomous vehicle. However, an automated vehicle controlled by traditional TBW in low-friction road conditions could reach large slip ratio region, which could adversely cause the loss of vehicle longitudinal dynamic stability. To tackle the mentioned issues, this paper proposes an adaptive sliding-mode control (SMC) algorithm to optimize tire slip speed of the automated vehicle. When the intervention conditions of active acceleration are satisfied, the TBW can take over the throttle opening control instead of the driver. Firstly, the SMC can calculate an intervention of the effective torque input based on tire torque balance dynamics. Moreover, a traction control system (TCS) and TBW coupling strategy based on the logic threshold method is put forward to response the optimum slip speed curve. Thus, during the vehicle starting process, a three-layer control strategy consisting of TBW, torque control, and pressure control of TCS is involved. Finally, real-car snow and ice road tests are carried out, and experimental results demonstrate great performance of the proposed strategy in complicated low-friction road.

Background:. It is currently unknown whether patients with a fever after controlled ovulation during egg retrieval could increase the risk of pelvic infection or not, and fever itself may affect endometrial receptivity or embryo quality with poor pregnancy outcomes. The aim of this study was to analyze the outcomes of patients with fever during oocyte retrieval after the first frozen-thawed embryo transfer (FET) cycle. Methods:. This was a 1:3 retrospective paired study matched for age. In this study, 58 infertility patients (Group 1) had a fever during the control ovulation, and the time of the oocyte retrieval was within 72 hours, they underwent ovum pick up and whole embryo freezing (“freeze-all” strategy). The control subjects (Group 2) are 174 patients matched for age who underwent whole embryo freezing for other reasons. The baseline characteristics, clinical data of ovarian stimulation, and outcomes, such as the clinical pregnancy rate, ongoing clinical pregnancy rate were compared between the two groups in the subsequent FET cycle. Results:. All patients had no pelvic inflammatory disease after oocyte retrieval. Anti-Mullerian hormone (AMH) levels (4.2 vs. 2.2, P

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 are concerned with a class of degenerate diffusion equations with time delay describing population dynamics with age structure. In our recent study [{\em Nonlinearity}, 33 (2020), 4013--4029], we established the existence and uniqueness of critical traveling wave for the time-delayed degenerate diffusion equations, and obtained the reducing mechanism of time delay on critical wave speed. In this paper, we now are able to show the asymptotic spreading speed and its coincidence with the critical wave speed $c^*(m,r)$ of sharp wave, and prove that the initial perturbation or the boundary of the compact support of the solution propagates at the critical wave speed $c^*(m,r)$ for the time-delayed degenerate diffusion equations. Remarkably, different from the existing studies related to spreading speeds, the time delay and the degenerate diffusion lead to some essential difficulties in the analysis of the spreading speed, because the time-delay makes the critical speed of traveling waves slow down, and the degenerate diffusion causes the loss of regularity for the solutions. By a phase transform technique combined with the monotone method, we can determine the asymptotic spreading speed. Furthermore, we propose a brand-new sharp-profile-based difference scheme to handle large variation of degenerate diffusion $(u^m)_{xx}$ near the sharp edge and carry out some numerical simulations which perfectly confirm our theoretical results.

This work reveals a novel mechanism by which pulmonary vascular endothelial cells, via regulating the transdifferentiation of microvascular pericytes into myofibroblasts, contribute to the pathogenesis of pulmonary fibrosis. Since targeting the formation of myofibroblasts may prevent the development and benefit the treatment of pulmonary fibrosis, this study provides not only mechanistic understanding but also promising therapeutic targets for pulmonary fibrosis.

This qualitative study explored the facilitators and barriers influencing professional mental health help-seeking among Malaysian LGBT young adults (n = 28). The main barriers identified were inter...

The Miocene aged Shanwang Formation from the Shanwang National Geopark in China represents a succession of lacustrine diatomaceous shales containing an abundant and diverse biota with lagerstatte fossilization of soft tissues. To date, the Shanwang Formation has not been investigated for cyclostratigraphy nor has it been dated with high precision methods. Now we use thorium data as a paleoenvironmental and paleoclimatic proxy to conduct a detailed cyclostratigraphic analysis. A new and simple cyclostratigraphic method, Wavelet Scale Series Analysis (WSSA) is developed to recognize Milankovitch cycles. A total of three short eccentricity and fifteen precession cycles are identified; obliquity cycles are not apparent. In the sedimentary succession, the corresponding precession and short eccentricity cycles are 1.17 m and 4.98 m thick respectively, with this verified by Correlation Coefficient (COCO) analysis and Multitaper-Method (MTM) spectral analysis. We estimate the studied interval was deposited over a duration of 0.3 Myr with a depositional rate of c. 5.7 cm/kyr. Paleomagnetic and radio isotope dating data shows that the diatomaceous shale was deposited during Chron C5En, which places it at approximately 18.5 Ma during the Burdigalian stage of the Early Miocene, rather than in the Middle Miocene as previously thought. The Shanwang lagerstatte biota therefore predates the Middle Miocene Climate Optimum (MMCO) and did not form within it. The geological time scale with a high resolution of 20 kyr was set accordingly.

In this paper, we investigate the existence and regularity of the smooth transonic steady solutions of Euler--Poisson equations representing for the hydrodynamic model of semiconductors. Different ...

Luminescent inorganic perovskite nanocrystals (PeNCs) are promising in various optical applications, particularly in advanced lighting and displays. The instability of PeNCs and PeNC composites from different aspects hinder their practical applications. Many previous methods indicate that an intact and facile wrapping strategy could effectively address this challenge. In this work, we introduce an in situ ligand polymerization (ILP) method for the fabrication of PeNC composites. By introducing (3-aminopropyl)triethoxysilane (APTES) as the initial ligand of the PeNCs directly and polymethylhydrosiloxane (PMHS) as the monomer to form the polymerized matrix, a polymerized and hydrophobic SiO2 matrix structure is formed, which intrinsically protects the PeNCs against moisture-induced deterioration. The stability test indicates that the ILP composite powders demonstrate an improved stability against various solvent conditions and light exposure compared to the conventional PeNCs–SiO2 composite. More importantly, the ILP composite exhibits an excellent compatibility with the acrylate solvent which is widely used for light-solidification in light converting film fabrication. The ILP composite film demonstrates an ultrastable operational performance in our standard test outperforming the conventional PeNCs–SiO2 composite configuration. Thus, the ILP composite demonstrates great potential for use in advanced lighting and displays.

Objective To investigate the feasibility and efficacy of deep brain stimulation (DBS) in the treatment of Parkinson's disease (PD) after pallidum or thalamus lesion, and to analyze its therapeutic strategy. Methods From December 2013 to December 2019, nine patients with PD whose symptoms recurred after nuclear lesion and underwent DBS were selected. MRI combined with microelectrode recording (MER) technology was used to locate the target, and patients were treated with DBS. The adverse events during and after awake anesthesia and postoperative follow⁃up were observed to evaluate the safety of operation, Unified Parkinson's Disease Rating Scale (UPDRS) and Activities of Daily Living Scale (ADL) were used to evaluate the improvement of postoperative symptoms and the efficacy of DBS. Results In this group of 9 patients, 2 patients were treated with unilateral subthalamic nucleus (STN) ⁃ DBS, the remaining 7 cases were treated with bilateral STN ⁃ DBS; the cell discharge frequency recorded on the ipsilateral and contralateral sides of the lesion was 400-500 Hz, without significant difference. There were no intraoperative and postoperative complications, and the symptoms of all patients were improved in varying degrees. After 3 months of stimulation, the UPDRS score of PD patients decreased from (115.56 ± 26.17) score to (32.56 ± 9.08) score, the difference was statistically significant (t = 10.853, P = 0.000); and the ADL score increased from (38.56 ± 6.09) score to (73.68 ± 19.07) score, the difference was statistically significant (t = 10.850, P = 0.000). There was no postoperative complication. Conclusions For PD patients who had undergone unilateral pallidotomy or thalamus lesion, if limb stiffness/tremor symptoms exist, as long as the STN nuclei have complete anatomical structure, selective STN⁃DBS assisted by MER is safe and feasible, and bilateral STN⁃DBS would be better. DOI：10.3969/j.issn.1672⁃6731.2020.12.004

AIM:To investigate the influence of myopia on peripapillary retinal nerve fiber layer thickness(RNFLT)using Cirrus optical coherence tomography(OCT)in myopic juveniles aged 12-18 years.METHODS: Cross-sectional observational study. High-definition(HD), spectral-domain Cirrus OCT(Cirrus HD-OCT; Carl Zeiss, Dublin, CA)was used to analyze RNFLT in 145 healthy juveniles(145 eyes). The data for left eye were selected for analysis. The magnification effect was adjusted by the modified axial length method. The subjects were divided into four groups by spherical equivalent(SE): normal group(52 eyes, -0.25-+0.25D), low myopia group(60 eyes, -0.5--3.0D), moderate myopia group(25 eyes, -3.25--6.0D)and high myopia group(8 eyes,-6.25--12.0D). The correlations between RNFLT and axial length(AL)or SE was tested with linear regression analysis.RESULTS: The older the age, the longer the eye axis length, the higher the degree of myopia. Comparison of adjusted RNFLT among the four groups: after adjustment, the average RNFLT of the low myopia group and the moderate myopia group were thicker than those of the normal control group(PPPr=0.220, 0.259, 0.356, 0.237, 0.335, all Pr=-0.386, -0.276,-0.307, -0.254, -0.260, all Pr=-0.296,-0.327, all Pr=0.245,0.295, all PCONCLUSION: Teenagers' eyeballs are still in the shaping stage. When judging RNFLT in myopic juveniles, effects of ocular magnification effect, AL and SE should be considered. When adjusted temporal RNFLT at 1-4 o'clock are thinner than normal, glaucoma should be considered.

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 aim of this paper is to give existence results for a class of coupled systems of fractional integrodifferential equations with Hilfer fractional derivative in Banach spaces. We first give some definitions, namely the Hilfer fractional derivative and the Hausdorff’s measure of noncompactness and the Sadovskii’s fixed point theorem.

A new triazine charring agent, melamine formaldehyde resin modified with pentaerythritol (named as MF-MPOL), was synthesized through hydroxymethylation, condensation and etherification by using melamine, paraformaldehyde and pentaerythritol as raw materials, and characterized by solid-state 13C NMR and FT-IR. The intumescent flame retardant (IFR) consisting of MF-MPOL with ammonium polyphosphate has good flame retardancy in polypropylene (PP). The analysis of the residues obtained in cone calorimetry test showed that the IFR played a role of flame retardancy mainly in condensed phase. In other words, the porous and dense - continuous intumescent char layer formed during the burning process results in flame retardant effect by insulation of heat, oxygen and preventing the underlying PP from degradation and volatilization of pyrolytic products.

For the classical reaction diffusion equation, the a priori speed of fronts is determined exactly in the pioneering paper (Benguria and Depassier 1996 Commun. Math. Phys. 175 221–227) by variational characterization method. In this paper, we study the age-structured population dynamics using a degenerate diffusion equation with time delay. We show the existence and uniqueness of sharp critical fronts, where the sharp critical front is C 1-smooth when the diffusion degeneracy is weaker with 1 < m < 2, and the sharp critical front is non-C 1-smooth (piecewise smooth) when the diffusion degeneracy is stronger with m ≥ 2, and the non-critical waves are C 2-smooth. We give a new variational approach for the critical wave speed and investigate how the time delay affects the propagation mechanism of fronts. It is shown that the time delay slows down the critical wave speed.

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.

The key process of sexual reproduction is the successful fusion of the sperm and egg cell. Distinct from dynamic and flagellated animal sperm cells, higher flowering plant sperm cells are immotile. Therefore, plants have evolved a novel reproductive system to achieve fertilization and generate progenies. Plant sexual reproduction consists of multiple steps, mainly including gametophyte development, pollen-pistil recognition, pollen germination, double fertilization and postfertilization. During reproduction, active production, consumption and recycling of cellular components and energy are critically required to achieve fertilization. However, the underlying machinery of cellular degradation and turnover remains largely unexplored. Autophagy, the major catabolic pathway in eukaryotic cells, participates in regulating multiple aspects of plant activities, including abiotic and biotic stress resistance, pathogen response, senescence, nutrient remobilization and plant development. Nevertheless, a key unanswered question is how autophagy regulates plant fertilization and reproduction. Here, we focus on comparing and contrasting autophagy in several key reproductive processes of plant and animal systems to feature important distinctions and highlight future research directions of autophagy in angiosperm reproduction. We further discuss the potential crosstalk between autophagy and programmed cell death, which are often considered as two disconnected events in plant sexual reproduction.

Neonatal vascular ophthalmopathy is a refractory ophthalmologic disease, and is a major cause of blindness. Occurrence of neonatal vascular ophthalmopathy may be associated with Paxillin, a cellular adhesion molecule which promotes the migration of endothelial cells and angiogenesis. To explore the role of PXN in corneal angiogenesis, human umbilical vein endothelial cells were divided into five groups: i) Control group; ii) Empty vector-transfected control group; iii) PXN knockdown group (shPXN group); iv) PXN-negative control (NC) group; and v) PXN over-expressed group (overExp group). PXN protein levels, migration and tube formation were assessed in the different experimental groups. Mice were divided into four groups: i) Control; ii) Model; iii) shPXN; and iv) overExp groups. Tube formation was significantly increased in the overExp group compared with the empty vector-transfected control group (P

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.

Southern blot analysis is an important molecular biology technique for identifying a specific sequence in DNA samples. Although it is no longer used extensively in recent years, the steps and underlying principles of Southern blot are applicable to modern biology. High sensitivity and limited background are keys to successful Southern blots, whereas obtaining good quality and quantity of genomic DNA as starting materials and detecting a single/low copy target sequence in the genome can be challenging. To ensure student success in performing the technique for the first time, a modified "plasmid-to-plasmid" Southern blot was implemented to confirm the presence of grape nucleotide-binding site (nbs) sequences in cloned plasmids like those described previously. The plasmid DNA and a control plasmid, pSCA7 (T1-T3-W6) containing a known grape nbs sequence, were digested with restriction enzymes, followed by agarose gel electrophoresis. The DNA band corresponding to the nbs sequence of the pSCA7 (T1-T3-W6) was extracted from the gel for PCR digoxigenin (DIG) probe synthesis. At the same time, the cloned plasmid DNA and its digested DNA fragments were blotted from the gel onto nylon membranes to be hybridized with the DIG probe followed by the detection for nbs sequences. Students successfully performed Southern blots to confirm the presence of nbs sequences in their cloned plasmids and wrote up the results following the format of scientific research papers. They learned the principles and applications of Southern blot and gained hands-on experience with associated techniques.

To compare the clinical effect between head acupuncture combined with exercise therapy and conventional acupuncture for nonspecific low back pain.A total of 64 patients with nonspecific low back pain were randomized into an observation group (32 cases, 2 cases dropped off) and a control group (32 cases, 2 cases dropped off). In the control group, conventional acupuncture was applied at Jiaji (EX-B 2) of LCompared before treatment, the VAS and ODI scores after treatment were decreased in the two groups (Head acupuncture combined with exercise therapy could relieve pain, improve dysfunction and increase the local temperature of pain area in patients with nonspecific low back pain, and its curative effect is better than conventional acupuncture.