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Existing infrared (IR) small target detection algorithms often lack adaptability in complex scenes and heavily rely on parameter configurations. To address this limitation, we propose a novel IR small target detection method based on adaptive region growing algorithm with iterative threshold analysis that leverages the homogenous compactness of the small target and discontinuity with its surroundings. Initially, the image undergoes adaptive splitting into multiple regions using an automatic seeded region growing (ASRG) algorithm, eliminating the need for preassigned seed points. Next, the segmentation results at each threshold are utilized to calculate the relative residual map (RRM) and local dissimilarity map (LDM), contributing to the selection of the optimal threshold. Finally, RRM and LDM corresponding to the optimal threshold are integrated to accurately characterize the small target signal while effectively removing background clutter. The experimental results show that the proposed method is effective in clutter removal and small target detection in diverse complex scenes and is robust to the shape and size of targets.

With the development of green tribology in the shipping industry, the application of water lubrication gradually replaces oil lubrication in stern bearings and thrust bearings. In terms of large-scale and high-speed ships, water-lubricated bearings with high performance are more strictly required. However, due to the lubricating medium, water-lubricated bearings have many problems such as friction, wear, vibration, noise, etc. This review focuses on the performance of marine water-lubricated bearings and their failure prevention mechanism. Furthermore, the research of marine water-lubricated bearings is reviewed by discussing its lubrication principle, test technology, friction and wear mechanism, and friction noise generation mechanism. The performance enhancement methods have been overviewed from structure optimization and material modification. Finally, the potential problems and the perspective of water-lubricated bearings are given in detail.

The passenger vehicle sector has been identified as a major contributor to carbon emissions in China. Accurately estimating carbon emissions is crucial, particularly in light of China's ambitious goal to reach its carbon emissions peak by 2030. Previous life cycle assessment (LCA) studies on single-passenger vehicles rarely consider technological advancements to accurately predict future carbon emissions in the entire fleet. As such, a fleet-based life cycle approach that integrates input-output-based hybrid LCA (IOH-LCA) and system dynamics is proposed to simulate the evolution of carbon emissions in the passenger vehicle sector from 2016 to 2035. This method captures the complex changes in the sets of vehicles produced for sale, in use, and disposed of over time, as well as the multiple time-dependent technological advancements. A scenario analysis is constructed to analyze carbon emissions in alignment with the commitment to achieving the carbon emissions peak by 2030. The results indicate that, in a positive scenario with the combined advancement of multiple technologies, the passenger vehicle sector will be able to peak carbon emissions before 2030. This study could provide support for policymaking regarding carbon reduction in China's electrification of passenger vehicles.

Urban sensing provides a fundamental computing environment for smart cities, in which ubiquitous vehicular networks are an important component. Due to the limitation of urban sensing resources, roadside units (RSU) are sparsely deployed in freeway-oriented vehicular networks. Thus, communication resources cannot cover all the vehicles everywhere and communication blind areas exist among RSUs. In urban sensing-based vehicular networks, the uncompleted content downloads of a vehicle within the current RSU range will be continued in the next RSU range. This will inevitably lead to some delay and influence user experience. To deal with such a challenge, this article proposes a novel vehicle–road urban sensing framework, to realize collaborative content delivery in freeway-oriented vehicular networks. It utilizes the collaboration of vehicle-tovehicle (V2V) communication and vehicle-to-infrastructure communication and sets up a corresponding content delivery mechanism oriented to the same direction and opposite direction of the object vehicle. Specifically, the proposed urban sensing framework develops a node clustering strategy for vehicles cruising in the same direction and a cooperative download strategy for vehicles cruising in the opposite direction. On this basis, theoretical analysis of the whole collaborative content delivery framework is carried out, to assess the performance of the proposal. The simulation results show that the proposal can have proper delivery ability under the guarantee of low latency.

Virtual reality (VR) is an important landing scenario for 5G and a key enabling technology for the digital economy, and the core challenge it faces is how to ensure real-time interaction and content distribution efficiency. Existing solutions rely on adaptive delivery, overall content edge caching, or asynchronous rendering in the cloud, with drawbacks such as high caching and computing costs and difficulty in ensuring real time. This article is oriented to content generation and synchronization of virtual reality, and aims at realizing intelligent transmission of VR content with high efficiency and low delay guarantee, and carries out research on cloud-edge-end collaborative mechanisms. First, for AI-aided VR content generation, a cloud-edge-end collaborative service architecture is constructed to support independent encoding and distribution of background and interactive content generation. Second, to address the issue that the MEC node with limited cache space cannot meet the dynamical demands of VR user, a cloud-edge collaborative caching strategy based on graph neural networks is proposed to achieve optimal caching and updating of background content, in which the background content is first cached MEC node according to the content request with node sharing scheme, then the content is updated according to a minimal cost update algorithm based on the graph neural networks (GNN)-aided request prediction. Finally, the proposed algorithm is simulated and tested, the simulation results show that the proposed caching and update algorithm achieve better quality of experiment (QoE) and higher cache hit ratio compared with comparison algorithms.

The rapid development of the Internet of Vehicles has substantially boosted the prevalence of vehicular social networks (VSN). However, content security has gradually been a latent threat to the stable operation of VSN. The VSN is a time-varying environment and mixed with various real or fake contents, which brings great challenges to the sustainability of VSN. To establish a sustainable VSN, it is of practical value to possess a strong ability for fake content detection. Related works can be divided into the global semantics-based approaches and the local semantics-based approaches, though both with limitations. Leveraging these two different approaches, this paper proposes a fake content detection model based on the mixed graph neural networks (GNN) for sustainable VSN. It takes GNN as the bottom architecture and integrates both convolution neural networks and recurrent neural networks to capture two aspects of semantics. Such a mixed detection framework is expected to possess a better detection effect. A number of experiments were conducted on two social network datasets for evaluation, and the results indicated that the detection effect can be improved by about 5%-15% compared with baseline methods.

Water-lubricated bearings have great advantages in the application of ship tail bearings due to the characteristics of green, pollution-free, and sustainable. However, the poor wettability of water-lubricated materials, as well as the low viscosity and poor load-carrying capacity of water, resulting in poor lubricating film integrity and short material service life under low-speed, heavy-load, start-stop conditions, which limits its application. To study the relationship between wettability and lubrication state and improve the lubrication performance of Si3N4under water lubrication conditions, the characteristic parameters that determine the hydrophilicity of Sphagnum were detected and extracted, and the bionic Si3N4model was established using Material Studio. Then, the molecular dynamic behavior and tribological properties of different Si3N4models were simulated and analyzed. Pore structure affects the spreading and storage of water on the material surface and changes the wettability of the material. Under the condition of water lubrication, better wettability and water storage promote the formation of water film, effectively improve the lubrication state of the material, and improve its bearing performance.

Lakes play important roles in sustaining the ecosystem and economic development in Inner Mongolia Autonomous Region of China, but the spatial patterns and driving mechanisms of water quality in lakes so far remain unclear. This study aimed to identify the spatial changes in water quality and the driving factors of seven lakes (Juyanhai Lake, Ulansuhai Lake, Hongjiannao Lake, Daihai Lake, Chagannaoer Lake, Hulun Lake, and Wulannuoer Lake) across the longitudinal axis (from the west to the east) of Inner Mongolia. Large-scale research was conducted using the comprehensive trophic level index (TLI (Σ)), multivariate statistics, and spatial analysis methods. The results showed that most lakes in Inner Mongolia were weakly alkaline. Total dissolved solids and salinity of lake water showed obvious zonation characteristics. Nitrogen and phosphorus were identified as the main pollutants in lakes, with high average concentrations of total nitrogen and total phosphorus being of 4.05 and 0.21 mg/L, respectively. The values of TLI (Σ) ranged from 49.14 to 71.77, indicating varying degrees of lake eutrophication, and phosphorus was the main driver of lake eutrophication. The lakes of Inner Mongolia could be categorized into lakes to the west of Daihai Lake and lakes to the east of Daihai Lake in terms of salinity and TLI (Σ). The salinity levels of lakes to the west of Daihai Lake exceeded those of lakes to the east of Daihai Lake, whereas the opposite trend was observed for lake trophic level. The intensity and mode of anthropogenic activities were the driving factors of the spatial patterns of lake water quality. It is recommended to control the impact of anthropogenic activities on the water quality of lakes in Inner Mongolia to improve lake ecological environment. These findings provide a more thorough understanding of the driving mechanism of the spatial patterns of water quality in lakes of Inner Mongolia, which can be used to develop strategies for lake ecosystem protection and water resources management in this region.

Exristing algorithms may suffer from high false alarm rate and low detection probability when detecting dim small target under intricate background clutters and heavy noise. To address this problem, a target detection method based on local image block analysis and center-surround gray difference measure (CGDM) is proposed in this article. First, the infrared image is decomposed into a group of local blocks. The gray information of each block are sorted in ascending order and the last element is deleted, then the maximum gray jump point (MGJP) is extracted by using differential operation. Second, a protection zone is formed with MGJP as the center, and the maximal intensity of protection zone (MIPZ) is extracted. Next, by comparing the gray intensity of MGJP and MIPZ values, the potential target blocks can be reliably selected, while most background blocks and noise blocks will be discarded. After that, the CGDM is presented to enhance the target and suppress background clutters, and then, the center-surround local contrast measure (CLCM) is designed to further suppress the high-intensity clutter residues by searching the target center and revising the protection zone. Finally, the weighted center-surround gray difference measure (WCGDM) is defined by CLCM WCGDM map to recognize real targets. Extensive experiments show that the proposed method outperforms several existing algorithms in small target detection under complex background clutters, and it is robust to various target shapes, target sizes, and noise types.

Real-time digital twin technology can enhance traffic safety of intelligent vehicular system and provide scientific strategies for intelligent traffic management. At the same time, real-time digital twin depends on strong computation from vehicle side to cloud side. Aiming at the problem of delay caused by the dual dependency of timing and data between computation tasks, and the problem of unbalanced load of mobile edge computing servers, a parallel intelligence-driven resource scheduling scheme for computation tasks with dual dependencies of timing and data in the intelligent vehicular systems (IVS) is proposed. First, the delay and energy consumption models of each computing platform are formulated by considering the dual dependence of sub-tasks. Then, based on the bidding idea of the auction algorithm, the allocation model of computing resources and communication resources is defined, and the load balance model of the mobile edge computing (MEC) server cluster is formulated according to the load status of each MEC server. Secondly, joint optimization problem for offloading, resource allocation, and load balance is formulated. Finally, an adaptive particle swarm with genetic algorithm is proposed to solve the optimization problem. The simulation results show that the proposed scheme can reduce the total cost of the system while satisfying the maximum tolerable delay, and effectively improve the load balance of the edge server cluster.

In ear of smart cities, intelligent medical image recognition technique has become a promising way to solve remote patient diagnosis in IoMT. Although deep learning-based recognition approaches have received great development during the past decade, explainability always acts as a main obstacle to promote recognition approaches to higher levels. Because it is always hard to clearly grasp internal principles of deep learning models. In contrast, the conventional machine learning (CML)-based methods are well explainable, as they give relatively certain meanings to parameters. Motivated by the above view, this paper combines deep learning with the CML, and proposes a hybrid intelligence-driven medical image recognition framework in IoMT. On the one hand, the convolution neural network is utilized to extract deep and abstract features for initial images. On the other hand, the CML-based techniques are employed to reduce dimensions for extracted features and construct a strong classifier that output recognition results. A real dataset about pathologic myopia is selected to establish simulative scenario, in order to assess the proposed recognition framework. Results reveal that the proposal that improves recognition accuracy about two to three percent.

As an important recreational water facility on cruise ships, swimming pool brings remarkable energy demand due to the requirement of comfort. In order to reduce the energy consumption during the operation of the swimming pool, this study proposes a hybrid heating system of air source heat pump water heater/chillers (ASHP) and exhaust gas boiler applicable to the cruise ship swimming pool by regarding the parameters of a Vista-class cruise ship resort pool. A simulation model is developed via TRNSYS for a dynamic simulation of energy demand under the predicted climate conditions of cruise line. According to the simulation results, a sizing method based on economy and comfort index is proposed for the capacity of the heat pump. The performance of heat pump partially replaced the existing method is also discussed, which proves the adoption of the ventilation system with variable air volume control can make the variation range of room temperature acceptable during the operation of the heat pump. Under the annual state of navigation and in-port, the proposed system (PS) shows significant economic, energy saving and emission advantages while ensuring comfort level when compared with the existing system (ES) of the same specification, while these advantages will be further expanded with the increase of in-port duration, pool area and service life.

In this paper, based on Lagrangian functions of the optimization problem we develop a sketch-and-project method for solving the linear matrix equation AXB=Cby introducing three parameters. A thorough convergence analysis on the proposed method is explored in details. A lower bound on the convergence rate and some convergence conditions are derived. By varying three parameters in the new method and convergence theorems, an array of well-known algorithms and their convergence results are recovered. Finally, numerical experiments are given to illustrate the effectiveness of recovered methods.

Two-dimensional ordered superstructures have been attracting considerable attention due to their interesting properties and potential applications. However, designing ideal functional superstructures with excellent electrochemical properties is still a major challenge, and an in-depth understanding of the structure–activity relationship of electrodes remains to be achieved. To elucidate this critical issue, herein, we rationally designed and synthesized for the first time superstructured TiO2/dual-doped mesoporous carbon anodes using confined space and surface coassembly strategies. Our method primarily relied on the larger interlayer space few-layered MXene and its negatively charged surface, allowing hexamethylenetetramine intercalation and surface electrostatic adsorption. The superstructured TiO2/dual-doped mesoporous carbon was successfully assembled by the thermal decomposition of a confined carbon precursor. Subsequently, the comparison of Na+-storage properties of various anodes was carried out based on the results of structural characterization techniques and electrochemical analysis methods. The results showed that the optimized anode (N/O-C@TiO2-20) can deliver a reversible capacity of 165 mA h g–1after 1000 cycles at a current density of 1 A g–1, indicating excellent electrochemical properties. The enhancement can be attributed to the synergistic effect of carbon domains, defective nanocrystals, and a covalently coupled interface between TiO2and mesoporous carbon. Our work not only offered a new strategy for the assembly and regulation of superstructures to promote the electrochemical performance but also enlightened the rational design of advanced anodes for sodium-ion battery application.

The running-in of cylinder liner-piston rings (CLPRs) is the most important process that must be performed before a marine diesel engine can be operated. The quality of running-in directly affects the reliability of a CLPR. The surface texture of a CLPR has been proven to significantly affect its lubrication performance. In this study, the tribological behavior of a CLPR during running-in is investigated. Three types of surface textures are generated on the CLPR via laser processing: dimple texture on piston rings, groove texture on cylinder liners, and co-texture on both sides. Subsequently, a series of tests are performed on a slice tester. A load of 300 N (1.64 MPa) is applied, and two speeds (50 and 100 rpm) are adopted. The CLPR running-in quality is characterized based on three parameters, i.e., the friction coefficient, contact resistance, and wear topography. Experimental results show that, compared with a non-textured surface, the three types of surface textures mentioned above improved the friction performance during running-in. The lubricant supply capacity of the dimple texture on the piston ring, as a mobile oil reservoir, is stronger than that of the groove texture on the cylinder liner serving as a static oil reservoir. By contrast, the wear resistance of the dimple texture, as a movable debris trap on the piston ring, is weaker than that of the groove texture on the cylinder liner, which serves as a static debris trap. It is demonstrated that the co-texture combines the advantages of dimples and groove textures. Compared with non-textured surfaces, the friction coefficient decreased the most at 100 rpm (44.5%), and the contact resistance improved the most at 50 rpm (352.9%). The coupling effect provides the surface with improved running-in quality by optimizing the tribological performance, particularly at the dead center. This study provides guidance for the tribological design and manufacturing of CLPR in marine diesel engines.

Background: Evidence has revealed a connection between cuproptosis and the inhibition of tumor angiogenesis. While the efficacy of a model based on cuproptosis-related genes (CRGs) in predicting the prognosis of peripheral organ tumors has been demonstrated, the impact of CRGs on the prognosis and the immunological landscape of gliomas remains unexplored. Methods: We screened CRGs to construct a novel scoring tool and developed a prognostic model for gliomas within the various cohorts. Afterward, a comprehensive exploration of the relationship between the CRG risk signature and the immunological landscape of gliomas was undertaken from multiple perspectives. Results: Five genes (NLRP3, ATP7B, SLC31A1, FDX1, and GCSH) were identified to build a CRG scoring system. The nomogram, based on CRG risk and other signatures, demonstrated a superior predictive performance (AUC of 0.89, 0.92, and 0.93 at 1, 2, and 3 years, respectively) in the training cohort. Furthermore, the CRG score was closely associated with various aspects of the immune landscape in gliomas, including immune cell infiltration, tumor mutations, tumor immune dysfunction and exclusion, immune checkpoints, cytotoxic T lymphocyte and immune exhaustion-related markers, as well as cancer signaling pathway biomarkers and cytokines. Conclusion: The CRG risk signature may serve as a robust biomarker for predicting the prognosis and the potential viability of immunotherapy responses. Moreover, the key candidate CRGs might be promising targets to explore the underlying biological background and novel therapeutic interventions in gliomas.

Water-lubricated bearing has become the development trend in the future because of its economy and environmental friendliness. The poor friction performance under low speed and heavy load seriously limits the popularization and application of water-lubricated bearings. Learning from nature, the phenomenon of low friction and wear in nature has aroused great interest of scientists, and a lot of research has been carried out from mechanism analysis to bionic application. In this review, our purpose is to provide guiding methods and analysis basis for the bionic design and theoretical research of anti-friction and anti-wear of water-lubricated bearings. The development of water-lubricated bearing materials are described. Some typical examples of natural friction reduction and drag reduction are introduced in detail, and several representative preparation methods are listed. Finally, the application status of bionic tribology in water-lubricated bearings is summarized, and the future development direction of water-lubricated bearings is prospected.

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An essential consideration in cyber-physical systems (CPS) is the ability to support secure communication services, such as points of interest (POI) microservices. Existing approaches to support secure POI microservices generally rely on anonymity and/or differential privacy technologies. There are, however, a number of known limitations with such approaches. Hence, this work presents a deep-federated-learning-based framework for securing POI microservices in CPS. In order to enhance data security, the system architecture is designed to isolate the cloud center from accessing user data on edge nodes, and an interactive training mechanism is introduced between the cloud center and edge nodes. Specifically, edge nodes pre-train reliable deep-learning-based models for users, and the cloud server coordinates parameter updating via federated learning. The connected and isolated structure between cloud center and edges facilitates deep federated learning. Finally, we implement and evaluate the performance of our proposed approach using two real-world POI-related datasets. The results show that our proposed approach achieves optimal scheduling performance and demonstrates its practical utility.

Previous diffusion tensor imaging (DTI) studies have reported that both mild cognitive impairment (MCI) and Alzheimer’s disease (AD) revealed microstructural changes [fractional anisotropy (FA)]. However, these results were not conclusive. The purpose of this meta-analysis was to identify the consistent FA alterations and the differences between MCI and AD. Case–control studies investigating MCI and AD using FA were searched in the online databases. The quantitative FA value of cognition-related brain regions was extracted and the standardized mean difference (SMD) with 95% confidence interval (CI) was calculated using fixed or random effect models. Twenty six studies with a total of 1,021 patients were included in this meta-analysis. Significantly decreased FA in patients with AD were identified in the left frontal lobe, corpus callosum (CC), fornix, hippocampus (HP), cingulate gyrus (CG), cingulate bundle (CB), uncinate fasciculus (UF), superior longitudinal fasciculus(SLF), the inferior fronto-occipital fascicles (IFOF), and the inferior longitudinal fasciculus(ILF) relative to MCI in this meta-analysis. This study provides objective and quantitative evidence that AD is associated with FA alteration within left frontal lobe, CC, FX, HP, CG, CB, and UF may suggest the key regions of the process from MCI to AD.

The growth model of black hole is still a controversial topic. In the stationary metric, all in-falling matter must be accumulated outside the event horizon of the black hole, as clocked by a distant external observer. In the time-dependent metric, all in-falling matter can fall into the event horizon of the final black hole within very short time. We test these two growth models by joining LIGO and Insight-HXMT observations. We find the stationary model is inconsistent with LIGO and Insight-HXMT observations.

Previous studies have shown that placebo repetitive transcranial magnetic stimulation (rTMS) was effective on post-stroke motor rehabilitation. However, the placebo effect has not been systematically assessed. Therefore, this meta-analysis was conducted to resolve this issue and explore potential influencing factors further. PubMed, Embase, web of science and the Cochrane Library were searched for published randomised controlled trials (RCTs) with placebo rTMS treatment of stroke recovery until May 2019. The placebo effect size (Hedges’ g) was estimated using the motor outcome of pre- and post- placebo rTMS treatment. Meta-regression analysis was also performed to explore potential influencing factors for the placebo effect. Twenty-six placebo-controlled trials (including 381 patients in placebo group) were selected. Effect size results (Hedges’ g= 0.466, 95% CI 0.207–0.726; P< 0.05) showed a medium and significant placebo rTMS effect on improving post-stroke motor recovery. The mean ratio of the effect size of sham to real stimulation was 56%. Meta-regression analysis did not find significant result except for the treatment sessions, which was significantly correlated with the placebo effect size (r= 0.465, p= 0.031). In the follow-up observations (1, 2 and 3 months), the sham rTMS groups manifested gradually increased motor improvement, which was similar to the real group, but the amplitude was lower, which was sustained for at least 3 months. Placebo effect of rTMS on post-stroke motor recovery was medium but significant. Regarding different sham styles, the number of stimulation sessions had an impact on the effect.

When the particle size of energetic materials is reduced to the nanoscale, significant changes occur in their properties and behavior. In this work, compression processes of three RDX nanoparticles (A, B, and C) were simulated using ReaxFF-lg. The mechanical, structural, and energetic responses of RDX nanoparticles during compression were revealed and characterized. Simulations reveal that the compression process of the nanoparticles can be divided into three stages: elastic stage, primary damage stage, and sustained damage stage. The temperature increase rate in the elastic phase is much lower than in the primary damage phase. In addition, we found that the smaller nanoparticle Bpresents a smaller elastic modulus and compressive strength, and it has a slower rate of temperature increase during the primary damage phase. Compared to cuboidal nanoparticles (Aand B), the spherical nanoparticle Ctends to absorb less energy during the elastic stage and exhibits slower damage rate during the primary damage stage. This is a key factor contributing to the low sensitivity of spherical nanoparticles.

This work describes synthetic strategies to access diverse chemical matter in a series of inhibitors of the cap-dependent Flu endonuclease. Our approaches toward this goal encompass (i) the development of a modular, diastereoselective route to the tricyclic cores and (ii) the use of advanced intermediates for late-stage diversification. Key to realizing both strategies is the development of an efficient, functional group-tolerant, chemoselective hydroformylation step that can be executed in the presence of the metal binding motif common to this inhibitor family. The established synthetic route provides access to advanced intermediates on gram scale. Furthermore, late-stage diversification conditions that tolerate the presence of the pyridone-based binding motif are reported, allowing for rapid access to a broad range of chemical matter.

Wireless power transfer (WPT) technology based on magnetic resonance (a basic physical phenomenon) can directly transfer energy from the source to the load without wires and other physical contacts, and has been successfully applied to implantable medical devices, electric vehicles, robotic arms and other fields. However, due to the frequency splitting of near-field coupling, the resonant WPT system has some unique limitations, such as poor transmission stability and low efficiency. Here, we propose anti-resonance with level pinning for high-performance WPT. By introducing the anti-resonance mode into the basic WPT platform, we uncover the competition between dissipative coupling and coherent coupling to achieve novel level pinning, and construct an effective anti-parity-time (anti-PT)-symmetric non-Hermitian system that is superior to previous PT-symmetric WPT schemes. On the one hand, the eigenvalue of the anti-PT-symmetric system at resonance frequency is always pure real in both strong and weak coupling regions, and can be used to overcome the transmission efficiency decrease caused by weak coupling, as brought about by, for example, a large size ratio of the transmitter to receiver, or a long transmission distance. On the other hand, due to the level pinning effect of the two kinds of coupling mechanisms, the working frequency of the system is guaranteed to be locked, so frequency tracking is not required when the position and size of the receiver change. Even if the system deviates from the matching condition, an efficient WPT can be realized, thereby demonstrating the robustness of the level pinning. The experimental results show that when the size ratio of the transmitter coil to the receiver coil is 4.29 (which is in the weak coupling region), the transfer efficiency of the anti-PT-symmetric system is nearly 4.3 (3.2) times higher than that of the PT-symmetric system when the matching conditions are satisfied (deviated). With the miniaturization and integration of devices in mind, a synthetic anti-PT-symmetric system is used to realize a robust WPT. Anti-PT-symmetric WPT technology based on the synthetic dimension not only provides a good research platform for the study of abundant non-Hermitian physics, but also provides a means of going beyond traditional near-field applications with resonance mechanisms, such as resonance imaging, wireless sensing and photonic routing.Using anti-resonance mode instead of resonance mode, a synthetic third-order non-Hermitian circuit with anti-PT symmetry is constructed, and wherein the novel level pinning effect enables efficient wireless power transfer.

The failures of mechanical structure featuring high nonlinearity, non-normal and non-independent are implicit function and small-probability events. This normally results in low computational efficient and accuracy for gradient algorithm scenario, which can hardly calculate models for large complex structure and flexible systems. To deal with the above constraints, an efficient and accurate reliability numerical method named adaptive reliability index importance sampling-based extended domain PSO (ARIIS-EDPSO) is proposed to combine the reliability numerical simulation and the particle swarm optimization (PSO) algorithm. The reliability index and limit state equation in ARIIS-EDPSO are regarded as the objective function and the constraint function. The Nataf transformation is adopted to complete the conversion process from an original variable space to an independent standard normal space, which only requires the marginal probability density function and the correlation coefficient among the random variables. To verify the effectiveness of the proposed ARIIS-EDPSO, experimental studies are conducted with five case studies. The results indicate that the constraint conflict function obtained via ARIIS-EDPSO is smaller than that is obtained via the other methods, and its convergence can be guaranteed. Also, the accuracy of the ARIIS-EDPSO is superior to the other methods for nonlinear reliability calculation. Furthermore, the ARIIS-EDPSO can accurately predict the failure probability. This approach exhibits advantageous global search ability, high efficiency and high accuracy in solving constrained reliability engineering problems. [ABSTRACT FROM AUTHOR]

Neoadjuvant chemotherapy (NAC) for rectal cancer (RC) shows promising clinical response. The modulation of the tumor microenvironment (TME) by NAC and its association with therapeutic response remain unclear. Here, we use single-cell RNA sequencing and spatial transcriptome sequencing to examine the cell dynamics in 29 patients with RC, who are sampled pairwise before and after treatment. We construct a high-resolution cellular dynamic landscape remodeled by NAC and their associations with therapeutic response. NAC markedly reshapes the populations of cancer-associated fibroblasts (CAFs), which is strongly associated with therapeutic response. The remodeled CAF subsets regulate the TME through spatial recruitment and crosstalk to activate immunity and suppress tumor progression through multiple cytokines, including CXCL12, SLIT2, and DCN. In contrast, the epithelial-mesenchymal transition of malignant cells is upregulated by CAF_FAP through MIR4435-2HGinduction, resulting in worse outcomes. Our study demonstrates that NAC inhibits tumor progression and modulates the TME by remodeling CAFs.

The effect of the inlet guide vanes on cavitation performance of an axial pump is investigated to assess the mechanism for cavitation in pumps and improve their cavitation performance. The effect of inlet guide vane angles on cavitation performance was assessed experimentally, and computational fluid dynamics was used to analyze the inner flow field of the axial pump and to probe the cavitation mechanism. The simulation results agree qualitatively with the experimental data, showing that cavitation performance is improved with positive inlet guide vane angles but hampered with negative ones. The cavitation performance itself is controlled by the cavitation volume, which first expands circumferentially when the net positive suction head decreases from a certain large value and then develops toward the axis radially after the net positive suction head reaches a certain value. This is when the cavitation performance deteriorates. Comparing cavitation volume for the critical net positive suction head as determined by two different methods, the method based on efficiency drop (NPSHeff.,1%) is found to be more suitable than that based on head drop (NPSHhead.,3%). Furthermore, the distribution of swirl is shown to be closely related to the distribution of cavitation, a feature that may be used to predict cavitation along the impeller.

The fabrication of mechanically robust polymeric materials capable of self-healing and recycling remains challenging because the mobility of polymer chains in such polymers is very limited. In this work, mechanically robust supramolecular thermosets capable of healing physical damages and recycling under mild conditions are fabricated by trimerization of bi-(ortho-aminomethyl-phenylboronic acid)- and tri-(ortho-aminomethyl-phenylboronic acid)-terminated poly(propylene glycol) oligomers (denoted as Bi-PBA-PPG and Tri-PBA-PPG, respectively). The resultant supramolecular thermosets are cross-linked by dynamic covalent bonds of nitrogen-coordinated boroxines. The mechanical properties of the supramolecular thermosets can be systematically tailored by varying the ratios between Tri-PBA-PPG and Bi-PBA-PPG, which changes the cross-linking density of nitrogen-coordinated boroxines and the topology of the supramolecular thermosets. The mechanically strongest supramolecular thermosets with a molar ratio of Tri-PBA-PPG to Bi-PBA-PPG being 1:2 have a glass transition temperature of ∼36 °C, a tensile strength of ∼31.96 MPa, and a Young’s modulus of ∼298.5 MPa. The high reversibility of nitrogen-coordinated boroxines and the flexibility of poly(propylene glycol) chains enable the supramolecular thermosets with the strongest mechanical strength to be highly efficiently healed at 55 °C and recycled under a pressure of 4 MPa at 60 °C to regain their original mechanical strength and integrity.

The interaction between cavity field and atoms plays an important role in exploring the abundant non-Hermitian physics and constructing powerful wave function devices. In this work, we propose theoretically and realize experimentally unidirectional perfect absorption in a non-Hermitian acoustic system with the help of the topological bound state in the continuum (BIC), which is established by the hybrid interaction between one trivial BIC and another conventional resonant state. In the 2D parameter space spanned by frequency and distance between the two resonators, the topological scattering singularities appear in pairs and are associated with topological distinguished charges. Meanwhile, we reveal the origin of topological charges and their continuous evolution with the loss factor. At a specific loss factor, two topological charges just annihilate together, and acoustic perfect absorption induced by topological BIC is realized at the left incidence, while there is no phase singularity and near-total reflection is observed at the right incidence, hence the system presents extreme asymmetry. Our work bridges the gap between scattering characteristics of non-Hermitian acoustic systems and topological scattering singularities, which may contribute to the research of novel non-Hermitian physics and the practical applications of advanced absorbers and sensors.

ABSTRACTSome people maintain Kautsky came up with a socialist premature birth theory and believe it has been somewhat verified. Actually, the premature birth theory conceived by Kautsky referred to the premature birth of socialism in Russia. Kautsky did not mean socialism was prematurely born. Socialism was not born insufficiently mature, but rather overdue. And even for the Russian socialism, the premature birth theory was of no eloquence. Actually, in Lenin’s theses, he absolutely ensured himself against skipping over the peasant movement, which had not outlived itself, or the petty-bourgeois movement in general, against any playing at “seizure of power” by a workers’ government, against any kind of Blanquist adventurism. He emphasized in the theses the need for patient and persistent “explanatory” work “adapted to the practical needs of the masses.” In July of 1917, the workers and the troops and sailors in Petrograd spontaneously held a mass demonstration, which showed a tendency to grow into a July Insurrection. Although the bourgeoisie provisional government could and should be overthrown, Lenin halted the mass demonstration because the revolution could only succeed when the working class attained the majority in the Soviets. In September of 1917, having attained a majority in the Soviets of Workers’ and Soldiers’ Deputies of both Petrograd and Moscow, Lenin stated the Bolsheviks “can and must take state power into their own hands.” Thus, with Lenin’s insistence, the masses of Russia overcame various interferences and won the victory of October Revolution.

Oleanolic acid derivative DKS26 has hypolipidemic, islet, and hepatoprotective effects. However, high lipophilicity and low water solubility led to DKS26 extremely low oral bioavailability. Herein, lipid‐based nanocarriers, including lipid nanodiscs (sND/DKS26) and liposomes (sLip/DKS26), are prepared to improve DKS26 oral absorption. In comparison to free DKS26 (5.81%), the absolute oral bioavailabilities are significantly increased to 29.47% (sND/DKS26) and 37.25% (sLip/DKS26) without detectable toxicity or immunogenicity even after repeated administrations. Both sND/DKS26 and sLip/DKS26 significantly reduce the feeding glucose level and the AUC of OGTT in db/db diabetic mice. Aiding by the newly developed scFv‐based nanocarrier separation methods, no intact nanocarriers are detected in blood circulation after oral administration, suggesting that both formulations are unable to penetrate the intestinal epithelium. They enhance DKS26 absorption mainly by improving intestinal cell uptake and rapid intracellular release of the payload. Since pre‐existing anti‐PEG is widely detected in humans, the present oral absorption pathway of both nanocarriers successfully avoids unfavorable immunological responses after interaction with anti‐PEG antibodies. The application of lipid‐based nanocarriers paves an efficient and safe avenue for the clinical translation and application of poorly soluble therapeutics derived from traditional Chinese medicine. Both lipid nanodiscs and liposomes dramatically enhance oral bioavailability of DKS26 and reduce the feeding glucose level and the AUC of OGTT in db/db diabetic mice. No intact nanocarriers are detected to penetrate the intestinal epithelium and enter blood circulation, providing a useful solution to avoid unfavorable immunological responses after interaction with widespread anti‐PEG antibodies in humans.

Enhancing the reliability of high-speed railway traction system is critical important to the safety of entire trains. Data-driven based FDD (Fault Detection and Diagnosis) schemes focused on electric locomotive traction system have received more and more attention. An improved Deep PCA (Principal Components Analysis) algorithm is presented in this paper, based on which, a KLD (Kullback–Leibler Divergence) based incipient FDD scheme is proposed at the same time. The main contributions are summarized as: (i) The improved Deep PCA algorithm by using the covariance matrix of the dataset (not the original dataset as references) can highlight more useful incipient fault information with much faster data decomposition; (ii) The diagnosis scheme based on KLD can improve the accuracy of non-Gaussian process; (iii) The study proposed in this paper can realize the update of fault database and the diagnosis of unknown type of incipient faults. The experiment results performed on TDCS-FIB (Traction Drive Control System-Fault Injection Benchmark) platform demonstrate the superiority of the proposed data-driven based incipient FDD scheme in comparison with the original Deep PCA algorithm.

A qualitative detection method for EGFRmutations is not sufficient to guide precise targeted therapy in clinical practice. The aim of this study was to explore the relationship between the abundance of EGFRmutations and efficacy of EGFR tyrosine kinase inhibitors (TKIs).

Magnetic resonance coupling plays an important role in the non-radiative wireless power transfer without cables. However, the basic near-field coupling also has some key limitations on the resonance wireless power transfer (WPT). On the one hand, when the transfer distance is short, the eigenfrequencies of the WPT system will split because of the strong near-field coupling between the resonance transmitter and receiver. On the other hand, although the working frequency is fixed for the long-distance case, the transfer efficiency will be significantly dropped for the weak coupling strength. Therefore, a long-captivated problem of the resonance WPT systems is that it is difficult to balance the fixed working frequency and high efficiency of the devices. In this work, we put forward the composite transmitter with a pair of resonance coils of different size. By assisting the rotational degrees of freedom in the composite transmitter, a high-order parity-time-symmetric non-Hermitian system can be established. Especially, in contrast to the conventional resonance WPT scheme, the robust WPT can maintain fixed working frequency and efficiency over a varying transfer distance in the optimized WPT system with composite transmitter, since this eigenfrequency is insensitive to the operational conditions. Our findings demonstrate that the composite transmitter possesses better performance for WPT than its single counterpart, offering the opportunities for engineering novel designer electromagnetic transfer states with unique robustness.

This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition (CVD) that has tungsten as its inner liner. The feasibility of this design was evaluated through penetration tests. Double-layer charge liners were fabricated by using CVD to deposit tungsten layers on the inner surfaces of pure T2 copper liners. The microstructures of the tungsten layers were analyzed using a scanning electron microscope (SEM). The feasibility analysis was carried out by pulsed X-rays, slug-retrieval test and static penetration tests. The shaped charge jet forming and penetration law of inner tungsten-coated double-layer liner were studied by numerical simulation method. The results showed that the double-layer liners could form well-shaped jets. The errors between the X-ray test results and the numerical results were within 11.07%. A slug-retrieval test was found that the retrieved slug was similar to a numerically simulated slug. Compared with the traditional pure copper shaped charge jet, the penetration depth of the double-layer shaped charge liner increased by 11.4% and >10.8% respectively. In summary, the test results are good, and the numerical simulation is in good agreement with the test, which verified the feasibility of using the CVD method to fabricate double-layer charge liners with a high-density and high-strength refractory metal as the inner liner.

The dynamics of air entrainment and suppression schemes in a pump sump are investigated. Four different turbulence models (standard k-εmodel, realizable k-εmodel, renormalization group (RNG) k-εmodel and shear-stress transport (SST) k-εmodel) and the volume of fluid (VOF) multiphase model are employed to simulate the three-dimensional unsteady turbulent flow in a pump sump. The dynamic processes of air entrainment are simulated under conditions of relatively high discharge and low submergence; the mechanism of air entrainment is discussed in detail. Then suppression means for air entrainment is adopted by placing a circular plate on the intake pipe at three different heights. The results show: the position and structure of the free-surface vortices, sidewall-attached vortices, back wall-attached vortices, and floor-attached vortices calculated by SST k-εturbulence model agree well with the experimental data. The two main contributors for air entrainment are pressure difference and vortex strength. By placing a circular plate in the middle of the intake pipe under water, air entrainment is suppressed because vortex strength is reduced.

17β-estradiol (E2) is one of the endocrine disrupting chemicals (EDCs) ubiquitously with significant impacts on ecosystem and organisms even at extremely low concentrations. Photocatalytic membranes, with the combination of photocatalysis and membrane filtration, have great potential to enhance E2 removal. In this work, a photocatalytic membrane was fabricated from the polyamide (PA) microfiltration membrane and visible light responsive Bi2WO6/protonated g-C3N4(BPG) photocatalyst. The BPG photocatalyst was embedded into calcium alginate hydrogel followed by immobilizing onto PA membrane through vacuum filtration and crosslinking. The transparent calcium alginate hydrogel guaranteed 100% light transmittance which contributed to visible light induced photodegradation. Under static and dynamic conditions, the removal efficiency of E2 reached 99.5% and remained 95.1%, which was mainly owing to the synergistic effects of the adsorption of PA and photodegradation of the BPG nanocomposites. The synergistic interaction was fitted by modified Elovich model, and a strong positive correlation (r = 0.834, rs= 0.965) was confirmed by Pearson’s and Spearman’s correlation coefficient, indicating that adsorption could enhance photocatalysis by concentrating contaminants around the photocatalyst and photocatalysis could promote the adsorption by regenerating adsorption sites. The photocatalytic membrane can be reused, and the removal efficiency of E2 was 96.6% after 5 cycles. This work provided not only a facile fabrication of photocatalytic membrane, but also a deep understanding of the synergistic adsorption-photocatalysis for effective removal of E2.

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive treatment tool for the recovery of cerebral palsy (CP). This report describes the modulation effect of rTMS to functional connectivity, functional network connectivity, motor, and cognitive ability following treatment in a child with mild ataxia CP. After receiving 8 months of 0.5 Hz rTMS treatment over the right dorsolateral prefrontal cortex, the child showed a gradual improvement in motor and cognitive-related functional connectivity and functional network connectivity following treatment as well as improved motor, cognitive functions. These pilot results provide the first evidence of the efficiency of 0.5 Hz of rTMS on a child with CP. Further large sample studies are needed to verify and expand the present findings.

The generation and control of valley pseudospin currents are the core of valleytronics. Here, the photonic analogy for generation and control of valley pseudospin currents using the pseudomagnetic fields induced in strained graphene is investigated in a microwave regime. In photonic graphene with uniaxial distortion, photons in two different valleys experience pseudomagnetic fields with opposite signs, and valley-dependent propagations in bended paths are observed. The external-field-free photonic transportation behavior may be very useful in controlling the flow of light in future valley-polarized devices.

In this study, the three-dimensional steady-state non-transferred plasma arc was investigated using computational fluid dynamics (CFD) with user defined functions (UDFs). A two-equation current density profile was developed to simulate the complex plasma flow inside the torch. The effect of the deviation distance (distance between the cathode tip center and the current density profile center) on the plasma flow features was systematically investigated for the first time. It is found that the temperature and velocity inside the plasma column reduce as the deviation distance increases, but the temperature near the arc-root attachment shows an increasing trend. Besides, it is also found that the arc length decreases with increasing the deviation distance. [ABSTRACT FROM AUTHOR]

By careful analyses to the available data to date, this paper discusses the issues on the custom of burying dogs in the burials in the prehistoric times, including the temporal and spatial distribution of dog burials, the different characteristics of the dog burials in different times and regions, the intentions of burying dogs in the human burials and the changes and evolutions of them, and so on, by which this paper suggests the origins of this custom and the cultural inheritance of the cultures in the historic period reflected by the appearances of this custom, and finally puts forward new clues of searching for the place of origin of the Shang civilization.

Oily wastewater poses a significant impact on both environments and human societies. Especially, the treatment of oil/water emulsions for separating oil from water is challenging due to the high stability of oil/water emulsions. Smart membranes, known as stimuli-responsive membranes, are one of the emerging technologies that have been paid wide attention for separating oil/water emulsions in recent years. Smart membranes possess the unique features of switchable wettability between hydrophilicity and hydrophobicity after being triggered by external stimuli and have desired anti-fouling properties. This review summarizes the development of smart membranes for oil/water emulsions separation during the past five years (2018 – present). It was found that solvent stimuli-responsive membranes are the most popular type of smart membranes for oil/water emulsions separation. For multi-stimuli-responsive membranes that can respond to more than one stimulus, future research should focus on developing appropriate fabrication strategies to increase the separation and anti-fouling performances of the membranes. Additionally, surface coating, surface grafting, and copolymer blending are the most popular methods for smart membranes fabrication. However, these methods might not be universally applicable to the different types of stimuli-responsive membranes.

Photocatalytic hydrogen peroxide (H2O2) production will become a burgeoning strategy for solar energy utilization by selective oxygen reduction reaction (ORR). Polymeric carbon nitride (PCN) shows relatively high two-electron ORR selectivity for H2O2production but still limited low H2O2production efficiency due to slow exciton dissociation. Herein, we constructed a heptazine/triazine layer stacked carbon nitride heterojunction with fluorine/potassium (F/K) dual sites (FKHTCN). The introduction of F/K not only can regulate layer components to enhance the charge separation efficiency but, more importantly, also optimize the adsorption of surface oxygen molecules and intermediate *OOH during H2O2production. Consequently, FKHTCN efficiently improves the photocatalytic H2O2production rate up to 3380.9 μmol h–1g–1, nearly 15 times higher than that of traditional PCN. Moreover, a production–utilization cascade system was designed to explore their practical application in environmental remediation. This work lays out the importance of engineering a layer-stacked configuration and active sites for enhancing photocatalysis.

The convection in an annular container with heated bottom, cooled top and insulated side walls are studied by both linear instability analysis and direct numerical simulation. The onset of convection is investigated by linear stability analysis and corresponding pattern selection mechanisms are discussed. The nonlinear evolution of different flow patterns and the convective heat transfer are simulated. The transition to oscillatory flow is also given by stability analysis where the base flow is a steady three dimensional flow. The stability predictions are in good agreement with the numerical simulations, including both the growth rate and the dimensionless frequency.

Cells obtained from growth of Achromobacter eurydice, Pseudomonas aromaticaand Pseudomonas putidaon l-phenylalanine containing medium catalyzed the enzymatic acyloin condensation of phenylpyruvic acid 1and acetaldehyde 2by phenylpyruvate decarboxylase to produce 3-hydroxy-1-phenyl-2-butanone 3. The acyloin condensation by Achromobacter eurydiceand P. aromaticawas stereoselective, providing the 3Renantiomer 3awith enantiomeric excess (ee) of 95% and 84%, respectively. A partially purified enzyme was prepared from the cell free extract of Achromobacter eurydice.The acyloin product 3awas obtained in 45% yield with an ee of 91% by using this partially purified preparation of phenylpyruvate decarboxylase.

Despite the great progress in OER catalyst research, obtaining desired coordination environment and optimized electronic structure of active center remains challenging. Here we propose a feasible strategy of changing the local coordination chemical environment of the active cations via introducing hetero-polyatomic anions based on the crystal field theory. A new type of two-dimensional Co-NO3-OAC[x:y]-HMT catalyst is first prepared in a water bath. It is discovered that adding OAC-into nanosheets containing NO3-can regulate both the morphologies and the electronic structure of as-prepared Co-based catalysts. As a result, the optimized Co-NO3-OAC[6:4]-HMT nanosheet aggregates exhibits an overpotential as low as 307 mV at the current density of 10 mA cm−2, and a small Tafel slop (62 mV dec−1). Moreover, the voltage attenuation of electrolysis in 1 M KOH alkaline medium for 10 h is only 8 mV. This superior electrochemical performance can be attributed to the induction effect of hetero-polyatomic anions. Our discovery provides a new insight into understanding the design of electrocatalysis based on anionic coordination chemistry.