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We demonstrate that a convex combination of the Nagumo and Perron growth conditions guarantees the existence of a unique solution to an ordinary differential equation, which can be obtained as the uniform limit of a sequence of successive approximations. Furthermore, we give a sufficient condition for the pathwise uniqueness of solutions to stochastic differential equations driven by Brownian motions. [ABSTRACT FROM AUTHOR]

Implantable biomedical patch used in treating abdominal wall defects requires antibacterial, anti‐adhesion, and pro‐healing activities to ensure surgical success and prevent postsurgical complications. However, it often encounters challenges in fulfilling these three critical properties simultaneously, as these processes can always be contradictory during treatment. Herein, to break the barriers between bactericidal activity and cytocompatibility, cell adhesion and anti‐adhesion, a bio‐inspired patch with an asymmetric Janus structure is developed. This bio‐inspired Janus patch features cicada wing‐inspired nanostructures on its top surface, enabling both mechano–bactericidal effects and promotion of fibroblast adhesion and proliferation, which stems from its inherent “selective biocidal activity” toward bacteria and mammalian cells. Subsequently, a poly‐zwitterion layer with robust nonfouling properties is grafted on the bottom surface, realizing cell adhesion and anti‐adhesion on two sides of the same patch. Compared to the commercially available polypropylene (PP) meshes, the top surface of the Janus patch, which faces the abdominal wall, demonstrates superior capabilities in preventing postoperative infection and promoting tissue repair. Simultaneously, the other side facing the viscera efficiently prevents any visceral tissue adhesion. With these prominent performances, the bio‐inspired Janus patch presents a pioneering strategy for designing next‐generation patches to treat abdominal wall defects. [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA) hydrogels have arisen as candidate materials to simulate the extracellular matrix and restore the functions of both cartilage and hard bones. However, integration of bone tissue adhesion and long-term osteogenic properties in one hydrogel is often ignored. Herein, a strategy to construct nanocomposite hydrogel with host tissue adhesive properties, enhanced mechanical strength, improved stability and osteogenic effects was developed. Simvastatin (SIM) was firstly incorporated into zeolitic imidazolate framework-8 (ZIF-8) and surface decoration with hydroxyapatite was realized to obtain SIM loaded and hydroxyapatite modified ZIF-8 particles (SP). As the inorganic strengthening component, SP could further cross-link the mixture of dopamine-hyaluronic acid (dHA) and tannic (TA) via coordination interaction to fabricate the hybrid adhesive hydrogel (dHA/TA/SP). Sufficient phenolic groups endowed dHA/TA/SP with excellent tissue adhesion and antibacterial properties, while incorporation of SP significantly improved the mechanical strength and stability of hydrogel. Further, due to the multiple protective effects of ZIF-8 and hydrogel, SIM was sustainably released from dHA/TA/SP. Together with the active Zn2+ and Ca2+, the expressions of ALP, OCN and RUNX2 were upregulated, and the mineralization was also promoted. With significant osteogenic effect in vitro and in vivo, this nanocomposite adhesive hydrogel holds great potential for bone defects repair. [Display omitted] [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA) hydrogels have arisen as candidate materials to simulate the extracellular matrix and restore the functions of both cartilage and hard bones. However, integration of bone tissue adhesion and long-term osteogenic properties in one hydrogel is often ignored. Herein, a strategy to construct nanocomposite hydrogel with host tissue adhesive properties, enhanced mechanical strength, improved stability and osteogenic effects was developed. Simvastatin (SIM) was firstly incorporated into zeolitic imidazolate framework-8 (ZIF-8) and surface decoration with hydroxyapatite was realized to obtain SIM loaded and hydroxyapatite modified ZIF-8 particles (SP). As the inorganic strengthening component, SP could further cross-link the mixture of dopamine-hyaluronic acid (dHA) and tannic (TA) via coordination interaction to fabricate the hybrid adhesive hydrogel (dHA/TA/SP). Sufficient phenolic groups endowed dHA/TA/SP with excellent tissue adhesion and antibacterial properties, while incorporation of SP significantly improved the mechanical strength and stability of hydrogel. Further, due to the multiple protective effects of ZIF-8 and hydrogel, SIM was sustainably released from dHA/TA/SP. Together with the active Zn2+ and Ca2+, the expressions of ALP, OCN and RUNX2 were upregulated, and the mineralization was also promoted. With significant osteogenic effect in vitro and in vivo, this nanocomposite adhesive hydrogel holds great potential for bone defects repair. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, a non‐standard finite difference scheme is developed to solve the space fractional advection–diffusion equation. By using Fourier–Von Neumann method, we prove that non‐standard finite difference scheme is unconditionally stable. We further discuss the convergence of numerical method and give the order of convergence. The numerical examples show that the non‐standard finite difference method can effectively reduce the maximum error and improve the accuracy of numerical solution in contrast to classical numerical methods. Moreover, we find that our numerical scheme is very flexible, when we optimize the denominator function of time and space simultaneously, the performance is the best. These studies show that the non‐standard finite difference scheme is feasible and efficient for solving fractional partial differential equations. [ABSTRACT FROM AUTHOR]

The prediction of carbon price is exceedingly essential for the regulators, investors, and participants of the carbon trading market. It is the basis for formulating market policies and improving risk management capabilities. China's carbon price series are nonlinear and nonstationary, so it is difficult to predict accurately with traditional models. This paper proposes a multiscale ensemble prediction model based on ensemble empirical mode decomposition (EEMD‐ADD) to improve the prediction accuracy of carbon price. Firstly, EEMD is used to decompose the carbon price sequence into several intrinsic mode functions (IMFs), and these IMFs are divided into high‐frequency component, low‐frequency component and the trend component. Then, LSSVM, PSO‐LSSVM, and BA‐LSSVM are used to predict the three components respectively after comparative analysis. Finally, the results are combined to obtain the final prediction value. In the empirical analysis of the Hubei Emissions Exchange, the proposed model outperforms other comparative models. The RMSE, MAE, and MAPE values of the EEMD‐ADD model are 0.6180, 0.4726, and 1.6342, and the DS, CP, and CD values are 94.36, 92.16, and 96.48. In addition, the model performed best in other time periods. The results suggest that the proposed model is effective and could predict carbon prices more accurately. [ABSTRACT FROM AUTHOR]

N-ethylcarbazole (NEC) is one of the most promising liquid organic hydrogen carriers (LOHCs) due to its low dehydrogenation enthalpy. The development of an efficient catalyst for the dehydrogenation of dodecahydro-N-ethylcarbazole (H 12 -NEC) is the key to the large-scale application of LOHCs. In this paper, Ni/MCM-41 was prepared by chemical reduction method using MCM-41 as the carrier, and then MCM-41 loaded Ni n @Pd 1 core-shell nanocatalysts (Ni n @Pd 1 /M41) were prepared by ultrasound-assisted galvanic replacement method using Ni as the templating agent and reducing agent. It was shown that there was electron transfer between Ni and Pd, and SMSI effect of Ni n @Pd 1 with MCM-41 by the characterization results of Ni n @Pd 1 /M41, which promoted the catalytic performance. H 12 -NEC dehydrogenation efficiency over Ni 6 @Pd 1 /M41 reached 100% at 180 °C for 4 h and at 170 °C for 6 h, and 97.58% for 6 h at 160 ℃, and TOF was 5080.6 h−1, which was better than that reported in the literature. The excellent catalytic dehydrogenation performance of Ni 6 @Pd 1 /M41 can mainly be attributed to the synergistic effect of coordination and strain effects between the bimetals. [Display omitted] • Ni n @Pd 1 /M41 core-shell catalysts for H 12 -NEC dehydrogenation were prepared by ultrasound-assisted galvanic replacement. • Coordination and strain effect between Ni and Pd, SMSI effect of Ni n @Pd 1 with MCM-41 improved the catalytic performance. • H 12 -NEC dehydrogenation efficiency over Ni 6 @Pd 1 /M41 reached 100% at 180 ℃ for 4 h and at 170 ℃ for 6 h. • TOF of H 12 -NEC dehydrogenation over Ni 6 @Pd 1 /M41 was 5080.6 h−1. [ABSTRACT FROM AUTHOR]

Interactive display is an important part of electronic devices. It is widely used in smartphones, laptops, and industrial equipment. To achieve 3-dimensional detection, the piezoelectric touch panel gains great popularity for its advantages of high sensitivity, low cost, and simple structure. In order to help readers understand the basic principles and the current technical status, this article introduces the work principles of the piezoelectric touch panel, widely-used piezoelectric materials and their characteristics, as well as the applications of the piezoelectric touch panel. The challenges and future trends are also discussed. [ABSTRACT FROM AUTHOR]

• A bactericidal shape memory polyurethanes (SMPU) composite film was prepared. • Biofilm can be detached from the surface of the film upon a thermal stimulation. • The SMPU composite film shows low cell cytotoxicity, without leaching of bactericidal species. Biofilms that are responsible for a variety of chronic infections and antibiotic resistance have drawn much attention worldwide. A new strategy for mechanically disrupting and removing biofilms by thermal-triggered shape memory polyurethanes (SMPU) film composited with zinc oxide nanoparticles (ZnO NPs) is reported here. Upon thermal triggered shape recovery, most of the adhered biofilm can be detached from the surface of the SMPU, while the incorporated ZnO NPs could efficiently eliminate the adhered initially and residual bacteria after detaching activity, without leaching of bactericidal species. Furthermore, the composite films exhibited low cytotoxicity to mammalian cells as revealed by cell viability tests. We envision that this antibacterial strategy may find unique applications in biomedical devices, especially for those biofilm-associated infections. [ABSTRACT FROM AUTHOR]

Owing to the limited natural distributions and special medicine-industrial values of Viola philippica , it's urgently needed to explore its population-level differences for promoting the resource utilization efficiencies of this plant. The hypothesis of this study was that different populations of V. philippica plants would have broad-scale differences and interactions of leaf-accumulated metabolites and leaf-colonized bacteria. Hence, two populations (vi-p and vi-j) of this plant were typically collected in China for analyzing multiomics. At first, vi-p and vi-j leaf metabolomes (LMs) were presented with 1,003 metabolites; in contrast of vi-p-LMs, 445 differently accumulated metabolites (DAMs) were identified in vi-j-LMs, with the only up-regulated lipids, vitamin and ketone compounds, the only down-regulated aldehyde compounds, the most up-regulated flavonoids, and the most down-regulated phenylpropanoid compounds. In comparative of vi-p leaf transcriptomes (LTs), 4,645 differently expressed genes (DEGs) were identified in vi-j-LTs, which were typically involved in a series of extracellular defenses and secondary metabolic pathways; the DEGs were frequently co-enriched with DAMs in three biosynthesis pathways of phenylpropanoid, flavonoid, and α-linolenic acid. Furthermore, these DAMs were also found to have the significant correlations with some different types or/and abundances of leaf-assembled bacteria (DTAB) between vi-p and vi-j leaf-assembled bacterial communities (LABCs). Taken together, this study reveals the broad-scale patterns of regulating vi-p and vi-j leaf DAMs with DEGs and DTAB, suggesting that it's essential of keeping plant-population and -habitat diversities for harvesting population-level DAMs in V. philippica. • The plant-level functional metabolites were integrally uncovered in V. philippica. • Two plant populations were identified with differently accumulated metabolites (DAMs). • The typical DAMs were co-enriched with differently expressed genes (DEGs). • These DAMs were also correlated with different types or/and abundances bacteria (DTAB). [ABSTRACT FROM AUTHOR]

• A new nanoprobe (DTAAT) has been designed based on DNA tetrahedral supported hybridization chain reaction (HCR) for in situ analysis of bacteria. • DTAAT can recognize bacteria by dual binding of antibody and aptamer, which improves specificity and sensitivity for in situ analysis of bacteria. • DTAAT as a nanoprobe can be used for in situ imaging and quantitative analysis of bacteria. A new nanoprobe (DTAAT) has been well designed based on DNA tetrahedron supported hybridization chain reaction (HCR) and further applied for in situ analysis of bacteria. Antibody-aptamer conjugate (AA) has been coupled with DNA tetrahedron (DT) followed by the linkage of trigger strand (A). Bacteria can be preciously recognized by dual binding of both antibody and aptamer in DTAAT, to release trigger strand which is complementary with aptamer. By virtue of proximity effect, the released trigger strand can further efficiently induce the simultaneous occurrence of arrays of HCR at three vertices of DT, with rapid reaction rate of 359.29 min−1 in comparison with that of 212.60 min−1 for free HCR. DTAAT can be served for in situ imaging of bacteria by confocal laser scanning microscopy and single-cell characterization by flow cytometry. Moreover, using DTAAT as probe, the quantitative analysis of bacteria can be realized with high specificity and anti-interference capability. In a word, the developed DTAAT nanoprobe has a great potential for accurate and sensitive in situ analysis of bacteria. [ABSTRACT FROM AUTHOR]

Constructing safe and effective antibacterial surfaces has continuously received great attention, especially in healthcare-related fields. Bioinspired mechano-bactericidal nanostructure surfaces could serve as a promising strategy to reduce surface bacterial contamination while avoiding the development of antibiotic resistance. Although effective, these nanostructure surfaces are prone to be contaminated by the accumulation of dead bacteria, inevitably compromising their long-term antibacterial activity. Herein, a bioinspired nanopillar surface with both mechano-bactericidal and releasing actions is developed, via grafting zwitterionic polymer (poly(sulfobetaine methacrylate) (PSBMA)) on ZnO nanopillars. Under dry conditions, this nanopillar surface displays remarkable mechano-bactericidal activity, because the collapsed zwitterionic polymer layer makes no essential influence on nanopillar structure. Once being incubated with aqueous solution, the surface could readily detach the killed bacteria and debris, owing to the swelling of the zwitterionic layer. Consequentially, the surface antibacterial performances can be rapidly and controllably switched between mechano-bactericidal action and bacteria-releasing activity, guaranteeing a long-lasting antibacterial performance. Notably, these collaborative antibacterial behaviors are solely based on physical actions, avoiding the risk of triggering bacteria resistance. The resultant nanopillar surface also enjoys the advantages of substrate-independency and good biocompatibility, offering potential antibacterial applications for biomedical devices and hospital surfaces. [Display omitted] • A bioinspired nanopillar surface (ZnO-PSBMA) was designed. • ZnO-PSBMA played switchable mechano-bactericidal and releasing actions. • These antibacterial behaviors were solely based on physical actions, avoiding the risk of triggering bacteria resistance. • ZnO-PSBMA nanopillar showed substrate-independency and good biocompatibility. [ABSTRACT FROM AUTHOR]

Sema4D, a member of the immune semaphorin family, plays crucial roles in the immune regulation, bone resorption and nervous system. It is also involved in angiogenesis and tumour progression. However, systemic studies on the correlation between Sema4D expression and the immune infiltration or clinical outcomes in tumours are still limited. Here, we analysed the landscape of Sema4D expression and its prognostic value in the cancer genome atlas pan-cancer as well as the correlation between Sema4D and immune cell infiltration by Tumour Immune Estimation Resource and Gene Expression Profiling interactive analysis online tools. Results showed that a higher Sema4D expression was significantly correlated with a favourable overall survival in diverse solid tumours including bladder cancer (Hazards Ratio (HR)=0.68, p =.0095), kidney renal clear cell carcinoma (HR = 0.61, p =.0016), melanoma (HR = 0.58, p = 6.6e-05) and thymoma (HR = 0.1, p =.011). Interestingly, Sema4D expression has positive correlation with various tumour infiltrating immune cells and immune cell biomarkers in these tumours. These results suggest that Sema4D could be a prospective biomarker for calculating hazard ratio of tumour patients and their tumour immune infiltration levels. [ABSTRACT FROM AUTHOR]

Developing highly active nonprecious electrocatalysts with superior durability for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is crucial to improve the efficiency of overall water splitting but remains challenging. Here, a novel superhydrophilic Co4N‐CeO2 hybrid nanosheet array is synthesized on a graphite plate (Co4N‐CeO2/GP) by an anion intercalation enhanced electrodeposition method, followed by high‐temperature nitridation. Doping CeO2 into Co4N can favor dissociation of H2O and adsorption of hydrogen, reduce the energy barrier of intermediate reactions of OER, and improve the compositional stability, thereby dramatically boosting the HER performance while simultaneously inducing enhanced OER activity. Furthermore, the superhydrophilic self‐supported electrode with Co4N‐CeO2 in situ grown on the conductive substrate expedites electron conduction between substrate and catalyst, promotes the bubble release from electrode timely and impedes catalyst shedding, ensuring a high efficiency and stable working state. Consequently, the Co4N‐CeO2/GP electrode shows exceptionally low overpotentials of 24 and 239 mV at 10 mA cm−2 for HER and OER, respectively. An alkaline electrolyzer by using Co4N‐CeO2/GP as both the cathode and anode requires a cell voltage of 1.507 V to drive 10 mA cm−2, outperforming the Pt/C||RuO2 electrolyzer (1.540 V@10 mA cm−2). More significantly, the electrolyzer has extraordinary long‐term durability at a large current density of 500 mA cm−2 for 50 h, revealing its potential in large‐scale applications. [ABSTRACT FROM AUTHOR]

The Kubuqi Desert is the only active sand sea in the semiarid regions of northern China and occurs along the southern margin of the Yellow River. Little is known about the age and origin of this large (17,000 km 2 ) sand sea with a present annual precipitation of 200‐480 mm. Sand drift potentials indicated net capable winds for aeolian transport are from the northwest, though winds are stronger to north beyond the dune field than within the sand sea. Geomorphic and stratigraphic observations indicate that Holocene aeolian sand often drapes over bedrock and river terraces as a palimpsest landscape. Field investigations identified four stratigraphic sections with multiple aeolian sand units and palaeosols, with age control by optically stimulated luminescence (OSL) dating of quartz grains. Palaeosols are weakly developed, mostly accumulative A horizon with organic carbon content < 1% and reflect sand sheet deposition possibly in a steppe environment. Although sediments near river channels or former lakes might give old ages, the initial formation and age of the Kubuqi sand sea should be judged from the occurrence of the sandy palimpsest of the landscape that is OSL dated to the Holocene in general. The latest period of aeolian reactivation may be related to human activity associated with grazing and farming from lost cities in the Kubuqi Desert during the Han (206 B.C. – A.D. 220) and the Tang (A.D. 608 – 907) Dynasties. Also, variable discharge of the Yellow River with local diversions for irrigation and throughout the catchment resulted in possibly an increased supply of aeolian particles for dune field expansion in the past 2 ka. [ABSTRACT FROM AUTHOR]