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Epithelial–mesenchymal transition (EMT)-related proteins (Slug, vimentin, and N-cadherin) are downregulated by Protein Z silencing, which significantly prohibits cellular proliferation and EMT activity (decrease of cellular migration and invasion) in non-small-cell lung cancer cells.

In this paper, we investigate a predator-prey system with fractional type cross-diffusion incorporating the Beddington-DeAngelis functional response subjected to the homogeneous Neumann boundary condition. First, by using the maximum principle and the Harnack inequality, we establish a priori estimate for the positive stationary solution. Second, we study the non-existence of non-constant positive solutions mainly by employing the energy integral method and the Poincaré inequality. Finally, we discuss the existence of non-constant positive steady states for suitable large self-diffusion $ d_2 $ or cross-diffusion $ d_4 $ by using the Leray-Schauder degree theory, and the results reveal that the diffusion $ d_2 $ and the fractional type cross-diffusion $ d_4 $ can create spatial patterns.

Abstract The safety problems encountered with lithium–sulfur batteries (LSBs) hinder their development for practical applications. Herein, a highly thermally conductive separator was constructed by cross‐weaving super‐aligned carbon nanotubes (SA‐C) on super‐aligned boron nitride@carbon nanotubes (SA‐BC) to create a composite film (SA‐BC/SA‐C). This separator was used to fabricate safe LSBs with improved electrochemical performance. The highly aligned separator structure created a uniform thermal field that could rapidly dissipate heat accumulated during continuous operation due to internal resistance, which prevented the development of extremely high temperatures. The array of boron nitride nanosheets endowed the composite separator with a large number of adsorption sites, while the highly graphitized carbon nanotube skeleton accelerated the catalytic conversion of high‐valence polysulfides into low‐valence polysulfides. The arrayed molecular brush design enabled the regulation of local current density and ion flux, and considerably alleviated the growth of lithium dendrites, thus promoting the smooth deposition of Li metal. Consequently, a battery constructed with the SA‐BC/SA‐C separator showed a good discharge capacity of 685.2 mAh g−1 over 300 cycles (a capacity decay of 0.026% per cycle) at 2 C and 60°C. This “three‐in‐one” multifunctional separator design strategy constitutes a new path forward for overcoming the safety problems of LSBs.

Abstract As a basic component in the field of computer vision, the pedestrian detection plays an essential role in several real‐world applications such as video surveillance. The promising performance has been achieved in pedestrian detection relying on deep learning, but large‐scale variance and small‐scale pedestrian detection remain inherently hard as before. In order to deal with the aforementioned problems, this paper proposes a multi‐scale pedestrian detection method with global–local attention and multi‐scale receptive field context (MRFC). To make the network focus on small‐scale pedestrians, we add a high‐resolution detection branch on the original detector. To better integrate the incongruous semantic feature, the global–local attention module is embedded to highlight the feature representation of pedestrians so as to implement the feature fusion effectively. In order to adapt the receptive field of the network to achieve scale‐variance detection, the MRFC is applied. Based on integrating the above structures, the proposed method achieves competitive results on Caltech and CityPersons datasets. The source code is released in https://github.com/xiaopan999/yolov5‐pedestrian_detection.

Highlights Design and fabrication of MXene-based soft actuators with angle-independent structural color. The nanostructured MXene can not only facilitate the formation of short-range ordered 3D amorphous photonic crystals, but also help significantly improve structural color saturation. The soft actuators exhibit brilliant angle-independent structural color, ultrafast actuation and recovery speeds in response to vapor.

The goal of relativistic heavy-ion collisions is to determine the phase boundary of quantum chromodynamics (QCD) phase transitions. Critically sensitive observables are suggested to be higher-order cumulants of conserved charges. The non-monotonous behavior of higher cumulants was observed at the relativistic heavy-ion collider (RHIC). However, it remains unclear whether these non-monotonous behaviors are critically related. We studied the influences of non-critical fluctuations, finite system size, and limited evolution time to determine if they cause non-monotonous behavior. First, we examined the minimum statistics required for measuring the fourth cumulant. The minimum statistic obtained using the centrality bin width correction (CBWC) method was 25 M. We suggest using a 0.1% centrality bin in the CBWC method instead of each Nch. With a 0.1 centrality bin width, 1 M statistics are sufficient. We then pointed out the statistical fluctuations from the limited number of final particles. By assuming the independent emission of each positive (or negative) charged particle, the statistical fluctuations of positive (or negative) charged particles were presented by a Poisson distribution, and the statistical fluctuations of net-charged particles were their evolution. The obtained statistical fluctuations for net protons, net electronic charges, and net baryons were consistent with those from the Hadron Resonance Gas model. In addition, the measured cumulants at RHIC/STAR are dominated by these Poisson-like statistical fluctuations. At the end of this section, we suggest the pooling method of mixed events and demonstrate that the sample of mixed events accurately presents the contributions of the background. Dynamic cumulants were defined as the cumulant of the original sample minus that of the mixed sample. Dynamical cumulants were shown to simultaneously reduce the influence of the statistical fluctuations, centrality bin width effects, and detector efficiency. Second, because the system is finite, the correlation length at the critical point is not developed to infinity in contrast to the system at thermal limits. Using a Monte Carlo simulation of the three-dimensional three-state Potts model, we demonstrated the fluctuations of the second- and fourth-order generalized susceptibilities near the temperatures of the external fields of the first-, second-, and crossover regions. Both the second- and fourth-order susceptibilities showed similar peak-like and oscillation-like fluctuations in the three regions. Therefore, non-monotonic fluctuations are associated with the second-order phase transition and the first-order phase and crossover in a finite-size system. The exponent of finite-size scaling (FSS) characterizes the order of transitions or crossover. To determine the parameters of the phase transition using the FSS, we studied the behavior of a fixed point in the FSS. To quantify the behavior of the fixed point, we define the width of the scaled observables of different sizes at a given temperature and scaling exponent ratio. The minimum width reveals the position of the fixed point in the plane of the temperature and scaling exponent ratio. The value of this ratio indicates the nature of the fixed point, which can be a critical, first-order phase transition line point, or crossover region point. To demonstrate the effectiveness of this method, we applied it to three typical samples produced by a three-dimensional three-state Potts model. The results show that the method is more precise and effective than conventional methods. Possible applications of the proposed method are also discussed. Finally, because of the limited evolution time, some processes in relativistic heavy-ion collisions may not reach thermal equilibrium. To estimate the influence of the nonequilibrium evolution, we used the three-dimensional Ising model with the Metropolis algorithm to study the evolution from nonequilibrium to equilibrium on the phase boundary. The order parameter exponentially approaches its equilibrium value, as suggested by the Langevin equation. The average relaxation time is defined. The relaxation time is well represented by the average relaxation time, which diverges as the zth power of the system size at a critical temperature, similar to the relaxation time in dynamical equations. During nonequilibrium evolution, the third and fourth cumulants of the order parameter could be positive or negative depending on the observation time, which is consistent with the calculations of dynamical models at the crossover side. The nonequilibrium evolution at the crossover side lasts briefly, and its influence is weaker than that at the first-order phase transition line. These qualitative features are instructive for experimentally determining the critical point and phase boundary in quantum chromodynamics.

The Lancang-Mekong Cooperation (LMC) is a new type of regional cooperation mechanism in the Greater Mekong Subregion (GMS). It was officially co-founded by six Lancang-Mekong countries in 2016. Water resources cooperation is the flagship field of the LMC. The goal of this article is to introduce comprehensively the LMC and to illustrate why it can be regarded as a new choice for regional water resources cooperation in the GMS. This paper first reviews the background to LMC's foundation, and then introduces the structural framework, operating mechanism and recent advances of the LMC. It will then analyze the deficiencies of the present water resources cooperation mechanisms in the GMS and the comparative advantages of water resources cooperation under LMC. Finally, some suggestions were given to improve and reinforce water resources cooperation under the LMC. This research concludes that the LMC is more suitable for the actual needs and objective reality of Lancang-Mekong countries owing to its high-level and all-round regional cooperation mechanism. It was established jointly by all riparian states, with a shared vision to enhance the well-being of six countries' people, and works to narrow the development gap among regional countries. Highlights Demonstrating the LMC is a new type of regional cooperation mechanism.; Discussing the advances and advantages of water cooperation under the LMC.; Summarizing the deficiency of existing organizations in water cooperation in the GMS.; Challenges and solutions of water cooperation under the LMC are analyzed.;

Abstract Background Emerging evidence suggests that microRNAs (miRs) are associated with the progression of osteoarthritis (OA). In this study, the role of exosomal miR-136-5p derived from mesenchymal stem cells (MSCs) in OA progression is investigated and the potential therapeutic mechanism explored. Methods Bone marrow mesenchymal stem cells (BMMSCs) and their exosomes were isolated from patients and identified. The endocytosis of chondrocytes and the effects of exosome miR-136-5p on cartilage degradation were observed and examined by immunofluorescence and cartilage staining. Then, the targeting relationship between miR-136-5p and E74-like factor 3 (ELF3) was analyzed by dual-luciferase report assay. Based on gain- or loss-of-function experiments, the effects of exosomes and exosomal miR-136-5p on chondrocyte migration were examined by EdU and Transwell assay. Finally, a mouse model of post-traumatic OA was developed to evaluate effects of miR-136-5p on chondrocyte degeneration in vivo. Results In the clinical samples of traumatic OA cartilage tissues, we detected increased ELF3 expression, and reduced miR-136-5p expression was determined. The BMMSC-derived exosomes showed an enriched level of miR-136-5p, which could be internalized by chondrocytes. The migration of chondrocyte was promoted by miR-136-5p, while collagen II, aggrecan, and SOX9 expression was increased and MMP-13 expression was reduced. miR-136-5p was verified to target ELF3 and could downregulate its expression. Moreover, the expression of ELF3 was reduced in chondrocytes after internalization of exosomes. In the mouse model of post-traumatic OA, exosomal miR-136-5p was found to reduce the degeneration of cartilage extracellular matrix. Conclusion These data provide evidence that BMMSC-derived exosomal miR-136-5p could promote chondrocyte migration in vitro and inhibit cartilage degeneration in vivo, thereby inhibiting OA pathology, which highlighted the transfer of exosomal miR-136-5p as a promising therapeutic strategy for patients with OA.

Background: Previous studies reported that melatonin exerts its effect on mesenchymal stem cell (MSC) survival and differentiation into osteogenic and adipogenic lineage. In the current study we aimed to explore the effect of melatonin on osteoporosis and relevant mechanisms. Methods: Real-time qualitative polymerase chain reaction (RT-qPCR) and Western blot analysis were conducted to determine expression of HGF, PTEN , and osteoblast differentiation-related genes in ovariectomy (OVX)-induced osteoporosis mice and the isolated bone marrow MSCs (BMSCs). Pre-conditioning with melatonin (1 μmol/l, 10 μmol/l and 100 μmol/l) was carried out in OVX mice BMSCs. Bone microstructure was analyzed using micro-computed tomography and the contents of alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase 5b (TRAP5b) were detected by enzyme-linked immunosorbent assay in serum. BMSC proliferation was measured by cell-counting kit (CCK)-8 assay. Alizarin red S (ARS) staining and ALP activity assay were performed to assess BMSC mineralization and calcification. The activity of the Wnt /β-catenin pathway was evaluated by dual-luciferase reporter assay. Results: Melatonin prevented bone loss in OVX mice. Melatonin increased ALP expression and reduced TRAP5b expression. HGF and β-catenin were downregulated, while PTEN was upregulated in the femur of OVX mice. Melatonin elevated HGF expression and then stimulated BMSC proliferation and osteogenic differentiation. Additionally, HGF diminished the expression of PTEN , resulting in activated Wnt /β-catenin pathway both in vitro and in vivo . Furthermore, melatonin was shown to ameliorate osteoporosis in OVX mice via the HGF / PTEN / Wnt /β-catenin axis. Conclusion: Melatonin could potentially enhance osteogenic differentiation of BMSCs and retard bone loss through the HGF / PTEN / Wnt /β-catenin axis.

Chitosan (CS) has been extensively studied as a natural polymer, in the field of wound repair, due to its useful properties, which include a lack of toxicity and stimulation, excellent biological affinity, degradability, and promotion of collagen deposition. However, inferior mechanical strength and moderate antibacterial properties are the drawbacks restricting its further clinical application. Many researchers have adopted the use of nanotechnology, in particular metallic nanoparticles (MNPs), in order to improve the mechanical strength and specific antibacterial properties of chitosan composites, with promising results. Furthermore, chitosan naturally functions as a reducing agent for MNPs, which can also reduce cytotoxicity. Thus, CS, in combination with MNPs, exhibits antibacterial activity, excellent mechanical strength, and anti-inflammatory properties, and it has great potential to accelerate the process of wound healing. This review discusses the current use of CS and MNPs in wound healing and emphasises the synergy and the advantages for various applications in wound healing.

Most reported wearable electronic devices lack self-healing chemistry and flexible function to maintain stable energy output while irreversible damages and complex deformations. In this work, we report a dual-dynamic network electrolyte synthesized by micellar elastomers introduced into strong hydrogel matrix. The gel electrolyte is fabricated by physically cross-linking the borax-polyvinyl alcohol (B-PVA) network as tough matrix and poly (ethylene oxide) (PEO)-poly (propylene oxide) (PPO)-poly (ethylene oxide) (Pluronic) to frame elastic network, followed by immersion in potassium chloride solution. Under the action of dynamic borate ester bond and multi-network hydrogen bond, the as-prepared electrolyte exhibits high stretchability (1535%) and good self-healing efficiency. Based on the electrolyte, we assemble the interfacial compatible micro-supercapacitor (MSC) by multi-walled carbon nanotubes (MWCNT) interdigital electrode printed on cellulosic paper by direct ink writing (DIW) technique. Thanks to the large specific area and compressive deformation resistance of cellulosic paper, the MSC with tightly interfacial contact achieves high volumetric capacitance of 801.9 mF cm−3 at the current density of 20 μA cm−2. In the absence of stimulation of the external environment, the self-healing MSC demonstrates an ideal capacity retention (90.43%) after five physical damaged/healing cycles. Our research provides a clean and effective strategy to construct wearable MSC.

Abstract Lithium (Li) metal anodes have garnered increasing interest in recent years as its high theoretical capacity and low electrochemical potential promises a myriad of opportunities for various applications. However, one critical issue to overcome is the inhomogeneous deposition of Li+ during the plating and stripping process. This inhomogeneous deposition could result in uncontrollable dendrite growth, further leading to poor coulombic efficiency, shorter lifecycles, and safety concerns due to internal short circuit and thermal runaways. To address these issues, a 3D porous core–shell fiber scaffold is presented, comprising of well‐dispersed SiO2, TiO2, and carbon, as superlithiophilic host materials for lithium anodes. The amorphous SiO2 and TiO2 allow for controllable nucleation and deposition of metal Li inside the porous core–shell fiber even at ultrahigh current densities of 10 mA cm−2. In addition, the interconnected conductive fiber with high porosity enables good electrical conductivity with fast ion transport and excellent mechanical strength to withstand massive Li loading during repeated cycles of stripping and plating. As a result, excellent cycling performance and high rate capability are observed in both symmetric cells and full cells, highlighting the feasibility of the proposed Li anode composite.

Narrow genetic background is a key limiting factor in breeding stable high-yielding rice. The introduction and utilization of international rice core germplasm is an important way to increase the genetic diversity of domestic rice varieties. We conducted a genome-wide association study on 5 panicle traits of 315 rice accessions introduced from the international rice micro-core germplasm bank. Based on the tests from Yangzhou of China and Arkansas of American, environment exhibited a significant impacts on panicle length and primary branch number, while grain length, grain width and grain length/width ratio were insensitive to environment changes. We discovered a total of 7, 5, 10, 8 and 6 chromosomal regions or single nucleotide polymorphism marker loci that were significantly associated with primary branch number, panicle length, grain length, grain width and grain length/width ratio, respectively. Among them, eleven regions were associated with grain shape and one region associated with primary branch number, showing the good consistence in two different environments. Significant linear correlation was discovered between the average trait value and the number of favorable alleles carried by the varieties in all associated loci. Among the associated loci, varieties in aromatic and tropical japonica sub-groups possessed most favorable alleles, while those in temperate japonica sub-group contained the least. The domestic varieties mainly harbored unfavorable alleles in six of the associated loci being detected. On the contrary, 15 varieties from 11 different countries harbored more favorable alleles (as many as 30 or more) than the others. Remarkably, all these 15 varieties belonged to the tropical japonica sub-group. In conclusion, our study demonstrates that varieties in the tropical japonica sub-group had high potentials for breeding stable high-yielding rice. Based on this discovery, we proposed a new approach for improving the panicle traits of domestic rice by using tropical japonica varieties.