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Biomimetic robotic fish are a novel approach to studying quiet, highly agile, and efficient underwater propulsion systems, attracting significant interest from experts in robotics and engineering. These versatile robots showcase their ability to operate effectively in various water conditions. Nevertheless, the comprehension of the swimming mechanics and the evolution of the flow field of flexible robots in counterflow regions is still unknown. This paper presents a framework for the self-propulsion of robotic fish that imitates biological characteristics. The method utilizes computational fluid dynamics to analyze the hydrodynamic efficiency of the organisms at different frequencies of tail movement, under both still and opposing flow circumstances. Moreover, this study clarifies the mechanisms that explain how changes in the aquatic environment affect the speed and efficiency of propulsion. It also examines the most effective swimming tactics for places with counterflow. The results suggest that the propulsion effectiveness of robotic fish in counterflow locations does not consistently correspond to various tail-beat frequencies. By utilizing vorticity maps, a comparative analysis can identify situations when counterflow zones improve the efficiency of propulsion. [ABSTRACT FROM AUTHOR]

Precision control of multiple robotic fish visual navigation in complex underwater environments has long been a challenging issue in the field of underwater robotics. To address this problem, this paper proposes a multi-robot fish obstacle traversal technique based on the combination of cross-modal variational autoencoder (CM-VAE) and imitation learning. Firstly, the overall framework of the robotic fish control system is introduced, where the first-person view of the robotic fish is encoded into a low-dimensional latent space using CM-VAE, and then different latent features in the space are mapped to the velocity commands of the robotic fish through imitation learning. Finally, to validate the effectiveness of the proposed method, experiments are conducted on linear, S-shaped, and circular gate frame trajectories with both single and multiple robotic fish. Analysis reveals that the visual navigation method proposed in this paper can stably traverse various types of gate frame trajectories. Compared to end-to-end learning and purely unsupervised image reconstruction, the proposed control strategy demonstrates superior performance, offering a new solution for the intelligent navigation of robotic fish in complex environments. [ABSTRACT FROM AUTHOR]

To address the increasing hydrogen demand and carbon emissions of industrial parks, this paper proposes an integrated energy system dispatch strategy considering multi-hydrogen supply and comprehensive demand response. This model adopts power-to-gas technology to produce green hydrogen, replacing a portion of gray hydrogen and incorporates a carbon capture system to effectively reduce the overall carbon emissions of the industrial park. Meanwhile, incentive-based and price-based demand response strategies are implemented to optimize the load curve. A scheduling model is established targeting the minimization of procurement, operation, carbon emission, and wind curtailment costs. The case study of a northern industrial park in China demonstrates that the joint supply of green and gray hydrogen reduces carbon emissions by 40.98% and costs by 17.93% compared to solely using gray hydrogen. The proposed approach successfully coordinates the economic and environmental performance of the integrated energy system. This study provides an effective scheduling strategy for industrial parks to accommodate high shares of renewables while meeting hydrogen needs and carbon reduction targets. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC), being ranked as the top fifth most prevalent cancer globally, poses a significant health challenge, with a considerable mortality rate. Hepatitis B virus (HBV) infection stands as the primary factor contributing to HCC, presenting substantial challenges in its treatment. This study aimed to identify lactic acid bacteria (LAB) with anti-HBV properties and evaluate their impact on the intestinal flora in HBV-associated HCC. Initially, two LAB strains, Levilactobacillus brevis SR52-2 (L. brevis SR52-2) and LeviLactobacillus delbrueckii subsp. bulgaicus Q80 (L. delbrueckii Q80), exhibiting anti-HBV effects, were screened in vitro from a pool of 498 LAB strains through cell experiments, with extracellular expression levels of 0.58 ± 0.05 and 0.65 ± 0.03, respectively. These strains exhibited the capability of inhibiting the expression of HBeAg and HBsAg. Subsequent in vitro fermentation, conducted under simulated anaerobic conditions mimicking the colon environment, revealed a decrease in pH levels in both the health control (HC) and HCC groups influenced by LAB, with a more pronounced effect observed in the HC group. Additionally, the density of total short-chain fatty acids (SCFAs) significantly increased (p < 0.05) in the HCC group. Analysis of 16S rRNA highlighted differences in the gut microbiota (GM) community structure in cultures treated with L. brevis SR52-2 and L. delbrueckii Q80. Fecal microflora in normal samples exhibited greater diversity compared to HBV-HCC samples. The HCC group treated with LAB showed a significant increase in the abundance of the phyla Firmicutes, Bacteroidetes and Actinobacteria, while Proteobacteria significantly decreased compared to the untreated HCC group after 48 h. In conclusion, the findings indicate that LAB, specifically L. brevis SR52-2 and L. delbrueckii Q80, possessing antiviral properties, contribute to an improvement in gastrointestinal health. [ABSTRACT FROM AUTHOR]

A rising incidence of clinical infections has been caused by Kluyvera, a significant opportunistic pathogen. Meanwhile, Kluyvera acts as an important reservoir of blaCTX-Ms, which are the dominant genes of class A extended-spectrum β-lactamases (ESBLs). In this work, 60 strains of Kluyvera were subjected to phylogenetic relationship reconstruction, antimicrobial susceptibility testing, and antibiotic resistance genes prediction. All mature blaCTX-Ms were gathered to perform subgroup reclassification. The findings demonstrate that Kluyvera has a large gene pool with significant genetic flexibility. Notably, 25% of strains showed simultaneous detection of ESBLs and carbapenem resistance genes. The genotypes of fourteen novel blaCTX-Ms were identified. A new subgroup classification approach for blaCTX-Ms was defined by using 20 amino acid site variants, which could split blaCTX-Ms into 10 subgroups. The results of the subgroup division were consistent with the phylogenetic clustering. More significantly, we proposed a novel blaCTX-M subgroup, KLUS, that is chromosomally encoded in K. sichuanensis and the new species put forward in this study, showing amino acid differences from the currently known sequences. Cloning and transformation tests demonstrated that the recipient bacteria had a robust phenotype of cefotaxime resistance. Closely related Kluyvera species had blaCTX-Ms in the same subgroup. Our research lays the groundwork for a deeper comprehension of Kluyvera and emphasizes how important a blaCTX-M reservoir it is. We provide an update on blaCTX-M subgroups reclassification from the aspects of phylogenetic relationship, amino acid differences, and the new subgroup KLUS, which needs to be strengthen monitored due to its strong resistance phenotype to cefotaxime. [ABSTRACT FROM AUTHOR]

The attainment of accurate motion control for robotic fish inside intricate underwater environments continues to be a substantial obstacle within the realm of underwater robotics. This paper presents a proposed algorithm for trajectory tracking and obstacle avoidance planning in robotic fish, utilizing nonlinear model predictive control (NMPC). This methodology facilitates the implementation of optimization-based control in real-time, utilizing the present state and environmental data to effectively regulate the movements of the robotic fish with a high degree of agility. To begin with, a dynamic model of the robotic fish, incorporating accelerations, is formulated inside the framework of the world coordinate system. The last step involves providing a detailed explanation of the NMPC algorithm and developing obstacle avoidance and objective functions for the fish in water. This will enable the design of an NMPC controller that incorporates control restrictions. In order to assess the efficacy of the proposed approach, a comparative analysis is conducted between the NMPC algorithm and the pure pursuit (PP) algorithm in terms of trajectory tracking. This comparison serves to affirm the accuracy of the NMPC algorithm in effectively tracking trajectories. Moreover, a comparative analysis between the NMPC algorithm and the dynamic window approach (DWA) method in the context of obstacle avoidance planning highlights the superior resilience of the NMPC algorithm in this domain. The proposed strategy, which utilizes NMPC, demonstrates a viable alternative for achieving precise trajectory tracking and efficient obstacle avoidance planning in the context of robotic fish motion control within intricate surroundings. This method exhibits considerable potential for practical implementation and future application. [ABSTRACT FROM AUTHOR]

Traditional transmission line fault diagnosis approaches ignore local structure feature information during feature extraction and cannot concentrate more attention on fault samples, which are difficult to diagnose. To figure out these issues, an enhanced feature extraction-based attention temporal convolutional network (EATCN) is developed to diagnose transmission line faults. The proposed EATCN suggests a new comprehensive feature-preserving (CFP) technique to maintain the global and local structure features of original process data during dimension reduction, where the local structure-preserving technique is incorporated into the principal component analysis model. Furthermore, to diagnose transmission line faults more effectively, a CFP-based attention TCN scheme is constructed to classify the global and local structure features of a fault snapshot dataset. To be specific, to cope with the gradient disappearance problem and improve learning capability, a skip connection attention (SCA) network is developed by incorporating a skip connection structure and two fully connected layers into the existing attention mechanism. By combining the developed SCA network with the conventional TCN's residual blocks, an EATCN-based diagnosis model is then constructed to dynamically pay attention to various imported global and local structure features. Detailed experiments on the datasets of the simulated power system are performed to test the effectiveness of the developed EATCN-based fault diagnosis scheme. [ABSTRACT FROM AUTHOR]

Recently, the traditional transmission line fault diagnosis approaches cannot handle the variables' dynamic coupling properties, and they also ignore the local structure feature information during the feature extraction. To figure out these issues, a novel enhanced feature extraction based convolutional LSTM (ECLSTM) approach is developed to diagnose the transmission line fault in this paper. Our work has three main contributions: (1) To tackle the dynamic coupling characteristics of the process variables, the statistics analysis (SA) method is first employed to calculate different statistical features of the transmission line's original data, where the original datasets are transformed into the subsequently used statistics datasets; (2) The statistics comprehensive feature preserving (SCFP) is then proposed to maintain both the global and local structure features of the constructed statistics datasets, where the locality structure preserving technique is incorporated into the principal component analysis (PCA) model to extract the features from the statistics datasets; (3) To effectively diagnose the transmission line's fault, the SCFP based convolutional LSTM fault diagnosis scheme is constructed to classify the global and local statistical structure features of fault snapshot dataset, because of its ability to exploit the temporal dependencies and spatial correlations of the extracted statistical features. Detailed experiments and comparisons on the datasets of the simulated power system are performed to prove the excellent performance of the ECLSTM based fault diagnosis scheme. [ABSTRACT FROM AUTHOR]

The path planning problem has gained more attention due to the gradual popularization of mobile robots. The utilization of reinforcement learning techniques facilitates the ability of mobile robots to successfully navigate through an environment containing obstacles and effectively plan their path. This is achieved by the robots' interaction with the environment, even in situations when the environment is unfamiliar. Consequently, we provide a refined deep reinforcement learning algorithm that builds upon the soft actor-critic (SAC) algorithm, incorporating the concept of maximum entropy for the purpose of path planning. The objective of this strategy is to mitigate the constraints inherent in conventional reinforcement learning, enhance the efficacy of the learning process, and accommodate intricate situations. In the context of reinforcement learning, two significant issues arise: inadequate incentives and inefficient sample use during the training phase. To address these challenges, the hindsight experience replay (HER) mechanism has been presented as a potential solution. The HER mechanism aims to enhance algorithm performance by effectively reusing past experiences. Through the utilization of simulation studies, it can be demonstrated that the enhanced algorithm exhibits superior performance in comparison with the pre-existing method. [ABSTRACT FROM AUTHOR]

Intestinal diseases caused by sleep deprivation (SD) are severe public health threats worldwide. However, whether or not probiotics attenuate the intestinal damage associated with SD remains unclear. In this study, we used antibiotic pretreatment and fecal microbiota transplantation to investigate the protective role of Lactiplantibacillus plantarum (L. plantarum) 124 against SD-related intestinal barrier damage in C57BL/6 mice. Compared with those of a normal sleeping mouse, we observed that intestinal antioxidant capacity and anti-inflammatory cytokine levels were decreased, while pro-inflammatory cytokines were increased in sleep deprivation mice with an increasing duration of sleep deprivation. This resulted in decreased tight junction protein expression and increased intestinal barrier permeability. In contrast, intragastric administration with L. plantarum 124 reversed SD-associated intestinal oxidative stress, inflammation, colonic barrier damage, and the dysbiosis of the microbiota in the colon. In addition, L. plantarum 124 restored gut microbiota homeostasis via restoring abundance, including that of Dubosiella, Faecalibaculum, Bacillus, Lachnoclostridium, and Bifidobacterium. Further studies showed that gut microbiota mediated SD-associated intestinal damage and the treatment L. plantarum 124 in SD-associated colonic barrier damage. L. plantarum 124 is a potential candidate for alleviating SD-associated intestinal barrier damage. Overall, L. plantarum 124 consumption attenuates intestinal oxidative stress, inflammation, and intestinal barrier damage in SD-associated mice via the modulation of gut microbes. [ABSTRACT FROM AUTHOR]

With the rapid development of human society, people's requirements for lighting are also increasing. The amount of energy consumed by lighting systems in buildings is increasing, but most current lighting systems are inefficient and provide insufficient light comfort. Therefore, this paper proposes an intelligent lighting control system based on a distributed architecture, incorporating a dynamic shading system for adjusting the interior lighting environment. The system comprises two subsystems: lighting and shading. The shading subsystem utilizes fuzzy control logic to control lighting based on the room's temperature and illumination, thereby achieving rapid control with fewer calculations. The lighting subsystem employs a Deep Deterministic Policy Gradient (DDPG) algorithm to optimize the luminaire dimming problem based on room illuminance in order to maximize user convenience while achieving uniform illumination. This paper also includes the construction of a prototype box on which the system is evaluated in two distinct circumstances. The results of the tests demonstrate that the system functions properly, has stability and real-time performance, and can adapt to complex and variable outdoor environments. The maximum relative error between actual and expected illuminance is less than 10%, and the average relative error is less than 5% when achieving uniform illuminance. [ABSTRACT FROM AUTHOR]

Analysis of Chinese real estate market shifted from eco nomic fundamentals to non-fundamentals, but consensus conclusions are still rarely reached. This is because institutional perspectives and national subjects are still lacking. Based on critical realistic approach, this paper integrates a state–society relationship and institution provision, constructing an analytical framework for the role of state capacity in the institutional construction of the real estate market. In terms of the intervention of the state on actors in the Chinese real estate market, the central government influences local governments, interest groups, and society at large through its administrative, extracting, and market service capacities, respectively, forming a chain of interests that serves the state–society relationship. [ABSTRACT FROM AUTHOR]

The accelerated development of antibiotic resistance genes (ARGs) and antimicrobial resistance (AMR) in aquaculture environments due to the overuse of antibiotics is a global concern. To systematically understand the research trends in and key concepts of ARGs and AMR in aquaculture systems, this study employed the bibliometrix R-package to conduct a bibliometric analysis of the publication characteristics of ARGs and AMR in aquaculture systems from the Web of Science, published from 2000 to 2021. The results revealed that China has produced the most papers. China and the northern hemisphere countries work closely together. Collaboration and multidisciplinary research helped to better understand the impact of AMR in aquaculture on food security and human health. Antibiotic-resistant bacteria and ARGs in aquaculture, as well as the relationship between water environmental variables, antibiotic residuals, and ARGs, are the current research focus. One of the future directions is to establish a conclusive link among water environmental variables, antibiotics, and ARGs. Another future direction is the development of new economical and environmentally friendly technologies to treat AMR in aquaculture wastewater. Collectively, our findings investigate the development directions of AMR research in global aquaculture systems and provide future perspectives. [ABSTRACT FROM AUTHOR]

A realistic and visible dynamic simulation platform can significantly facilitate research on underwater robots. This paper uses the Unreal Engine to generate a scene that resembles real ocean environments, before building a visual dynamic simulation platform in conjunction with the Air-Sim system. On this basis, the trajectory tracking of a biomimetic robotic fish is simulated and assessed. More specifically, we propose a particle swarm optimization algorithm-based control strategy to optimize the discrete linear quadratic regulator controller for the trajectory tracking problem, as well as tracking and controlling discrete trajectories with misaligned time series through introducing a dynamic time warping algorithm. Simulation analyses of the biomimetic robotic fish following a straight line, a circular curve without mutation, and a four-leaf clover curve with mutation are carried out. The obtained results verify the feasibility and effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

CO2 adsorption is one of the promising CCS technologies, and activated coke is a solid adsorbent with excellent adsorption properties. In this study, activated coke was prepared by using bituminous coal and coconut shells activated with KOH or CaCl2 in a physically activated atmosphere and modified with ammonia. The effect of the active agent impregnation ratio on the physicochemical properties of activated coke was investigated by N2 adsorption isotherms, scanning electron microscopy (SEM) and Fourier transform infrared spectrometry (FTIR). The CO2 adsorption performance of activated coke was tested, and the effect of nitrogen-containing functional groups on CO2 adsorption was investigated by experiments and simulations. The results showed that the specific surface area of activated coke reached 629.81 m2/g at a KOH impregnation ratio of 0.5 and 610.66 m2/g at a CaCl2 impregnation ratio of 1. The maximum CO2 adsorption capacity of activated coke reached 71.70 mg/g and 90.99 mg/g for conventional power plant flue gas and oxy–fuel combustion flue gas, respectively. After ammonia modification, the CO2 adsorption capacity of activated coke was further increased. Simulations showed that pyrrole and pyrrole functional groups changed the polarity of graphene and established weak interactions with CO2. [ABSTRACT FROM AUTHOR]

Radix aconiti carmichaeli is a widely used traditional Chinese medicine that has been found to be effective in treating cardiovascular diseases and metabolic disorders. Patients with these diseases often experience a heat generation disorder, which is characterized by chilliness and can worsen the progression of the disease. This study established an in vitro screening model combining the examination of cellular mitochondrial membrane potential and mitochondrial temperature to screen drugs with thermogenic activity. After differentiation and determination of the content of characteristic metabolites of the drug-containing serum blood components, it was found that Fuziline (FZL) is the key thermogenic property in Radix aconiti carmichaeli, responsible for its thermogenic effects with a high relative importance of 33%. Experiments were conducted to evaluate the thermogenic activity of Radix aconiti carmichaeli and FZL in vivo by assessing temperature changes in various organs, including the rectum, liver, and brown adipose tissue. Moreover, the effects of intracellular β3-adrenergic receptor (β3-AR) agonistic effects were evaluated using transient β3-AR transfection and dual-luciferase assay systems. The molecular mechanism by which FZL promotes thermogenesis and improves mitochondrial function was investigated by verifying the β-adrenergic receptors (β-AR) downstream signaling pathway. The results suggest that FZL activates β-AR nonselectively, which in turn activates the downstream cAMP-PKA signaling pathway and leads to an increase in liver glycogenolysis and triglyceride hydrolysis, accompanied by enhancing mitochondrial energy metabolism. Consequently, the liver and brown adipose tissue receive energy to generate heat. In summary, these findings provide insight into the therapeutic application of Radix aconiti carmichaeli for metabolic disorders associated with heat generation disorders. [ABSTRACT FROM AUTHOR]

Existing studies on rehabilitation robots are generally devoted to robot-assisted active rehabilitation training, which is conducive to facilitating muscle and nerve regeneration. However, human–robot interaction (HRI) requires imposing a limit on the workspace within which the robot operates, so as to ensure patient safety. A safe admittance boundary algorithm for a rehabilitation robot is proposed based on the space classification model which works by constructing a virtual boundary for the HRI workspace in the control layer. First, point cloud isodensification is performed for the workspaces within which the human body and the robot operate. Next, the nearest neighbor density is determined for the point cloud, and the space classification model is built on this basis. Finally, the space classification model is integrated with admittance control to derive the safe admittance boundary algorithm, which can be used for safety control. This algorithm is then subjected to space verification experiments and out–of–bounds experiments using a dynamic arm simulator (DAS). As indicated by the experimental results, when the side length of the voxel grid for voxel center filtering is set to 0.06 m, the accuracy of space definition is 98.40%. The average maximum response time for out–of–bounds behaviors is 165.62 ms. The safe admittance boundary algorithm can impose reasonable virtual constraints on the robot workspace, thereby improving HRI safety. [ABSTRACT FROM AUTHOR]

This paper applies the von Bertalanffy growth equation to study the age structure and growth characteristics of 210 Ptychobarbus dipogon collected in September 2019 in the middle and upper reaches of the Yarlung Zangbo River and employs FISAT II software to estimate the population characteristics' parameters. Its aim is to provide a basis for the conservation of the population resources of the Ptychobarbus dipogon. In this study, the length of the catch ranged from 137 mm to 475 mm, the weight ranged from 44.04 g to 1142.80 g, the minimum age was 5 years, and the maximum age was 47 years. The body length–weight relationship was W(♀) = 4.1738 × 10−5L2.7687 (n = 86, R2 = 0.901); W(♂) = 2.7784 × 10−5L2.8434 (n = 100, R2 = 0.918). The growth equation was Lt(♀) = 505.000[1 − e−0.048(t−1.992)]; Lt(♂) = 452.254[1 − e−0.069(t−4.233)]; Wt(♀) = 1296.576[1 − e−0.048(t−1.992)]2.7687; Wt(♂) = 1001.872[1 − e−0.069(t−4.233)]2.8434. The inflection point ages of the female and male Ptychobarbus dipogon were 7.95 and 6.05, respectively. The exploitation rate of Ptychobarbus dipogon was 0.61, which exceeds the optimum exploitation rate of resources (0.57). The population resources are overfished. It is suggested to strengthen the conservation of Ptychobarbus dipogon population resources and the protection of native fish on the Qinghai–Tibet Plateau. [ABSTRACT FROM AUTHOR]

Land use change has significant impacts on the regional and global environment; thus, in-depth research on the associated ecological risks is necessary for promoting ecological restoration and sustainable development. Xinjiang, China, is characterized by a fragile ecological environment, and this study aimed to predict the land use change in the region in 2030 under different scenarios, including natural development, ecological conservation, and urban development, by using the PLUS model based on land use data from 2000, 2010, and 2020. Based on the landscape structure of regional ecosystems, we developed a comprehensive ecological risk assessment framework by utilizing a combination of landscape disturbance index, vulnerability index, and loss index. This framework allowed us to evaluate the spatiotemporal patterns and variations of landscape ecological risks under different scenarios in 2030. The study results indicate the following: (1) During the period from 2000 to 2020, the primary landscape type in Xinjiang was unused land. However, significant changes were observed in the area of cultivated land, mainly due to the conversion of grassland and construction land. The expansion of construction land during the urbanization process resulted in a decline in ecological landscapes, such as grassland, thereby weakening the ecosystem's stability. (2) Under different simulation scenarios, the urban development scenario primarily led to the conversion of unused land into construction land, which is beneficial for economic development. On the other hand, the ecological conservation scenario resulted in a modest increase in construction land and a transformation of unused land into forest and grassland, which aligns with the principles of sustainable development. (3) Different scenarios in 2030 result in varying degrees of changes in each landscape type in Xinjiang, with the spatial distribution characteristics of landscape ecological risks remaining similar to those observed in 2020. Notably, under the urban development scenario, the area of lowest and medium risk areas decreases significantly while the area of higher and highest risk areas increases substantially. Conversely, under the ecological conservation scenario, the area of the lowest risk areas experiences a more significant increase. (4) Overall, the spatial differences in the ecological risk of Xinjiang's landscape are significant, with HH and LL clustering types predominating and presenting a polarization pattern. The distribution pattern is low in the north and high in the central and southern parts of the study area. [ABSTRACT FROM AUTHOR]

The Lhasa River is one of the five tributaries of the Yarlung Zangbo River. It is the main industrial, agricultural and animal husbandry area in Tibet. It plays an important ecological security barrier role in regulating regional climate and maintaining biodiversity. In order to understand the resource utilization ability and relationship of fish in Lhasa River, and provide basic data for the protection and sustainable utilization of fish diversity in Lhasa River, the fishery resources in September 2019 (autumn), June 2020 (summer), November 2020 (winter) and March 2021 (spring) were investigated for the first time. The main fish in the catch were determined by the Index of Relative Importance (IRI). Shannon index and Pianka's index were used to analyze the niche breadth and overlap values of the main fish caught in Lhasa River Basin from three dimensions of time, space and space–time. The results show that a total of 1399 fish of 3 orders and 4 families were collected. Among them, there is one dominant species, Schizopygopsis younghusbandi, and five common species, Schizothorax waltoni, Schizothorax oconnori, Ptychobarbus dipogon, Triplophysa stenura and Carassius auratus. The spatial–temporal niche breadth ranges from 1.395 to 3.628. They are Schizopygopsis younghusbandi, Carassius auratus, Ptychobarbus dipogon, Schizothorax oconnori, Triplophysa stenura and Schizothorax waltoni in a declining order. The temporal niche breadth is generally small, indicating that the survival activities of the main fish are greatly affected by seasonal changes. The fluctuation range of spatial–temporal overlap value is 0–0.535, and only 20% of the total logarithm is meaningful. The species pairs with temporal niche overlap values exceeding 0.300 reached 80%, while the spatial niche overlap value is generally low. The results show that the spatial and temporal distributions of the main fish in Lhasa River were quite different, and the spatial and temporal niche overlap value of the relationship between species is obviously affected by the change in spatial distribution. This demonstrates that the competition relationship and intensity of the main fish are quite different in different spatial positions. [ABSTRACT FROM AUTHOR]

An experimental study was carried out on the ignition characteristics of the HAN/(Emim)(EtSO4) (hydroxylammonium nitrate and 1-ethyl-3-methyl-imidazolium ethyl sulfate) dual-mode ionic liquid monopropellant in chemical propulsion mode in model thrusters. Firstly, a model thruster with a detachable convergent nozzle was designed and fabricated. Secondly, catalytic ignition experiments at different flow rates were carried out in atmosphere and in high chamber pressure environment, respectively, using a model thruster, with and without the convergent nozzle. During the catalytic ignition process, measurement methods such as thermocouple, pressure sensor, and flue gas analyzer were employed to obtain the temperature at different depths of the catalytic bed, the pressure of the combustion chamber, and the concentration variations of gaseous products CO, CO2, CH4, SO2, NO, and NO2. Then the three characteristic stages of water evaporation, HAN decomposition, and (Emim)(EtSO4) combustion were analyzed at the initiation time, and the reaction characteristics in the process of the catalytic ignition were analyzed. In addition, the composition and concentration of the combustion products at equilibrium were theoretically calculated. The effects of temperature and pressure on the concentrations of five main gaseous products were studied. Finally, the exhaust gas of the three groups of catalytic ignition experiments under different pressure environments was separately collected and measured with gas chromatography (GC) when the experiments approached equilibrium, the result of which roughly agrees with the theoretical calculations. These results are of great significance for exploring the chemical propulsion of the dual-mode ionic liquid propellant and understanding its physical catalytic combustion mechanisms. [ABSTRACT FROM AUTHOR]

To understand the characteristics of Vibrio isolates in aquatic environments in China and their public health significance, this study investigated water samples in six cities in China in 2020. A total of 88 sampling locations were included and Vibrio isolates were identified in 81 of them. A total of 143 Vibrio isolates belonging to 16 species were selected for characterization. The population structure of Vibrio species showed great differences among the six cities, indicating regional specificity. The presence of virulence genes was examined for the isolates (n = 78) of five pathogenic Vibrio species. All isolates except one (n = 77) contained at least one virulence gene and isolates belonging to the same species showed very similar virulence gene profiles. Then, 26 isolates from 12 species were examined by multilocus sequence typing and were assigned to 25 STs, of which 24 STs were new. Also, the presence of antibiotic-resistant genes was investigated for all 143 isolates and only three isolates were found to contain genes from aminoglycosides, phenicols, beta-lactams or the tetracycline family. Our results provide valuable insights into the Vibrio community in Chinese aquatic environments and can be applied as guidance for the environmental surveillance of the risk of Vibrio isolates. [ABSTRACT FROM AUTHOR]

Staphylococcus spp., especially Staphylococcus aureus (S. aureus), is an important pathogen in hospital-acquired infection and food poisoning. Here, we developed a multienzyme isothermal rapid amplification combined with duplex quantitative PCR (duplex MIRA-qPCR) method, which can simultaneously detect the S. aureus species-specific conserved gene FMN-bgsfp and the Staphylococcus genus-specific conserved gene tuf. This assay enabled the amplification of DNA within 20 min at a constant temperature of 39 °C. Specificity analysis indicated that all nine common Staphylococcus species were positive and non-Staphylococcus spp. were negative for tuf gene, whereas S. aureus was positive, non-aureus Staphylococci species and non-Staphylococcus spp. were negative for FMN-bgsfp gene, suggesting that duplex MIRA-qPCR exhibited high specificity. Meanwhile, the sensitivity was tested and the limit of detection (LoD) was 3 × 102 CFU/mL. The coefficient variation values ranged from 0.13% to 2.09%, indicating that the assay had good repeatability. Furthermore, all the nine common Staphylococcus species (including S. aureus) could be detected from four kinds of simulated samples and the LoD of S. aureus was 8.56 × 103 CFU/mL. In conclusion, the duplex MIRA-qPCR has advantages of stronger specificity, lower detection threshold, shorter detection time, and simpler operation, which is an effective tool to detect S. aureus and non-aureus Staphylococci spp. infections rapidly. [ABSTRACT FROM AUTHOR]

The efficient utilization of energy in rich fuel detonation processes and the effective control method of soot are important topics in combustion research. In this paper, we numerically study the detonation wave behavior of acetylene–air systems in rich fuel condition by using a reduced reaction mechanism. The non-stiff terms of the governing equations are solved explicitly using the gas kinetic scheme, and the stiff terms are solved implicitly. Our results show that the acetylene pyrolysis is the dominant reaction process. The oxidation reaction is exploited to initiate the reaction induction process, providing the required energy to overcome the potential energy barrier. The secondary detonation structure is due to the stable interaction of the transverse waves and the combined action of the vinyl reaction system, thus effectively improve the energy release rate and providing a powerful solution for the fuel-rich high-energy release of advanced heat engines. The area of the unreacted pocket increases with the acetylene concentration, resulting in an irregular wave-front and detonation cell. The reflected shock wave impacting on the wall induces the secondary reaction of the detonation products. The concentration of polycyclic aromatic hydrocarbons decreases significantly and regenerates near the wall. Our approach provides an effective tool for controlling detonation soot and the preparation of carbon particles. [ABSTRACT FROM AUTHOR]

A wall surface inspection robot mainly relies on the inertial measurement unit and global positioning system (GPS) signal during intelligent wall surface inspection. The robot may encounter incorrect positioning under a GPS-denied environment, easily triggering safety accidents. In order to obtain a path suitable for the safe work of the robot wall surface inspection robot in a GPS-denied environment, a global path-planning method for wall surface inspection robots was proposed based on the improved generic algorithm (GA). The influencing factor for GPS signal strength was introduced into the heuristic function in path planning for GA to address the aforementioned problem. Using the PSO algorithm, GA was initialized and the influencing term of GPS signal was introduced into the fitness degree function so as to achieve point-to-point path planning of vertical wall surface inspection robot. Path angle and probability of intersection and variation was taken into account for better path planning capability. Finally, the simulation experiments were performed. The generated path using the improved GA was found to avoid the blind area of the GPS signal. The algorithm proposed has a good performance with average convergence times of 35.9 times and an angle of 55.88° in simple environment. Contrary to the traditional GA and PSO algorithm, the method showed advantages in terms of the convergence rate, path quality, path angle change, and algorithm stability. The research presented in this article is meaningful and relatively sufficient. The simulation test is also quite convincing. The proposed method was proved to be effective in global path planning for a wall surface inspection robot. [ABSTRACT FROM AUTHOR]

Tracking and grasping a moving target is currently a challenging topic in the field of robotics. The current visual servo grasping method is still inadequate, as the real-time performance and robustness of target tracking both need to be improved. A target tracking method is proposed based on improved geometric particle filtering (IGPF). Following the geometric particle filtering (GPF) tracking framework, affine groups are proposed as state particles. Resampling is improved by incorporating an improved conventional Gaussian resampling algorithm. It addresses the problem of particle diversity loss and improves tracking performance. Additionally, the OTB2015 dataset and typical evaluation indicators in target tracking are adopted. Comparative experiments are performed using PF, GPF and the proposed IGPF algorithm. A dynamic target tracking and grasping method for the robot is proposed. It combines an improved Gaussian resampling particle filter algorithm based on affine groups and the positional visual servo control of the robot. Finally, the robot conducts simulation and experiments on capturing dynamic targets in the simulation environment and actual environment. It verifies the effectiveness of the method proposed in this paper. [ABSTRACT FROM AUTHOR]

A global path planning method is proposed based on improved ant colony optimization according to the slow convergence speed in mobile service robot path planning. The distribution of initial pheromone is determined by the critical obstacle influence factor. The influence factor is introduced into the heuristic information to improve the convergence speed of the algorithm at an early stage. A new pheromone update rule is presented using fuzzy control to change the value of pheromone heuristic factor and expectation heuristic factor, adjusting the evaporation rate in stages. The method achieves fast convergence and guarantees global search capability. Finally, the simulation results show that the improved algorithm not only shortens the running time of global path planning, but also has a higher probability of obtaining a global optimal solution. The convergence speed of the algorithm is better than the traditional ant colony algorithm. [ABSTRACT FROM AUTHOR]

In order to improve the adsorption efficiency of biochar in water treatment, biochar–graphene (BG) composites were prepared by the one-step dip coating method and applied to remove phthalates from water. Firstly, the materials and equipment needed for the experiment are introduced. The steps of preparing graphene oxide (GO) by the improved Hummers method and BG composites by one-step dip coating are discussed. Then, the morphology characterization, adsorption performance measurement, and isothermal model of BG composites are introduced. Finally, the structure characterization, adsorption kinetics, and adsorption isotherms of BG composites are analyzed. The results show that the properties of biochar could be changed by one-step dip coating, and the biochar could form composites with graphene. Compared with biochar, biochar–graphene composites have greater surface area and porosity. When the pyrolysis temperature was 600 °C, the specific surface area of biochar was 8.4 m2g−1, and the specific surface area of the biochar–graphene composite was 221.3 m2g−1. When the temperature was 300 °C, the specific surface area of biochar was 11.01 m2g−1, and the specific surface area of biochar–graphene composite was 251.82 m2g−1. The formation of graphene on the surface of biochar can increase the stability of the composite and acts as a very high potential active site. The porous structure and surface properties of biochar–graphene composites regulate the adsorption rate of pollutant molecules, thereby improving the adsorption performance. When the adsorption equilibrium was reached, the adsorption effect of phthalate esters on the biochar/graphene composite at the pyrolysis temperature of 600 °C was the best, and the adsorption capacity of Dimethyl phthalate (DMP)was 35.2 mg/g, that of Diethyl phthalate (DEP) was 26.4 mg/g, and that of Dibutyl phthalate (DBP) was 25.1 mg/g. The adsorption effect of DMP was the best. The results of the isotherm study indicate that the adsorption of phthalates by BG composites has great potential, which provides a good theoretical basis for the application of BG composites in environmental protection in China. [ABSTRACT FROM AUTHOR]

As Nb films are widely used as superconducting electrodes of Josephson junctions, it is important to investigate the properties of Nb films in order to fabricate high-quality Josephson junctions. In this work, we conducted a comprehensive analysis of the relationships among the properties of DC magnetron sputtered Nb films with a constant power fabricated at the National Institute of Metrology (China). The film properties, including superconductivity, stress, lattice constant, and surface roughness, were investigated. It was found that in the case of constant power and Ar pressure, the stress and other parameters of the Nb films can maintain a relatively stable state during the continuous consumption of the target material. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the associations between intakes of fibre from the main food sources of fibre in the UK diet with body mass index (BMI), percentage body fat (%BF), waist circumference (WC) and C-reactive protein (CRP). Participants enrolled in the Airwave Health Monitoring Study (2007–2012) with 7-day food records (n = 6898; 61% men) were included for cross-sectional analyses. General linear models evaluated associations across fifths of fibre intakes (total, vegetable, fruit, potato, whole grain and non-whole grain cereal) with BMI, %BF, WC and CRP. Fully adjusted analyses showed inverse linear trends across fifths of total fibre and fibre from fruit with all outcome measures (ptrend < 0.0001). Vegetable fibre intake showed an inverse association with WC (ptrend 0.0156) and CRP (ptrend 0.0005). Fibre from whole grain sources showed an inverse association with BMI (ptrend 0.0002), %BF (ptrend 0.0007) and WC (ptrend 0.0004). Non-whole grain cereal fibre showed an inverse association with BMI (Ptrend 0.0095). Direct associations observed between potato fibre intake and measures of body composition and inflammation were attenuated in fully adjusted analyses controlling for fried potato intake. Higher fibre intake has a beneficial association on body composition, however, there are differential associations based on the food source. [ABSTRACT FROM AUTHOR]

This study designed (Ti0.55Cu0.20Zr0.15Ni0.10)1−xSix amorphous alloys based on binary deep eutectics and examined the effect of silicon (Si) on the amorphous forming ability of the filler alloys. The results show that a certain amount of Si added to the filler metals could improve the amorphous forming ability of the alloys. Under the same experimental conditions, the Ti0.55Cu0.20Zr0.15Ni0.10 filler metal with 0.5 wt % Si had the strongest amorphous forming ability compared to the other filler alloys containing different amounts of Si; its reduced glass transition temperature (Trg) was 0.5554, and its supercooled liquid phase region width (∆Tx) reached 60 °C. The (Ti0.55Cu0.20Zr0.15Ni0.10)99.5%Si0.5% filler metal designed in these experiments presented good amorphous forming ability and wettability. The brazed joint of SiC and TC4 obtained with this amorphous filler metal showed a shear strength of 102 MPa, indicating an increase of 122% compared to the brazed joint obtained with the filler metal without Si. [ABSTRACT FROM AUTHOR]