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The interfacial friction performance of the liner system has an important influence on the overall stability of modern landfills, but the interface of the liner system using conventional geomembranes may have problems such as shear failure and slip along the liner system. Accordingly, the concept of a ribbed geomembrane was proposed. Based on the laboratory model tests, the variation laws of p–s curves and the additional stress of sand were studied under different values of shape, rib spacing, and rib height. A series of particle image velocimetry (PIV) analyses of sand particles were performed to provide insight into the reinforcement mechanism of the ribbed geomembrane liner system. The results indicated that the ribbed geomembrane could obviously improve the stability of the liner system compared with the smooth geomembrane. The ribbed geomembrane formed an indirect influence area with sand in a specific range. The ribbed geomembrane with optimal values of rib spacing and rib height was beneficial to reduce the settlement of the upper sand and the stress redistribution of the sand particles.

China is facing the dual challenges of fostering economic growth and mounting an effective response to climate change, so it is vital to continue promoting industrial carbon emission reduction. This paper uses panel data from 1998 to 2019 to measure the industrial carbon emissions of 30 provinces in China. The Tapio decoupling and IPAT (Impact = Population × Affluence × Technology)-based decoupling models are used to analyze each province’s velocity and quantity decoupling index for industrial carbon emissions. The fixed effect model analyzes the influencing factors for carbon decoupling. The results show that the industrial carbon emissions of various provinces in China are increasing yearly, but there are significant differences among provinces. The carbon decoupling of the industrial economy in most provinces is weak, and the quantitative decoupling index is better than the velocity decoupling index. The cleanliness of energy, balance, and labor productivity significantly affect the velocity decoupling index. The cleanliness of energy, the industry’s structure, and the population significantly affect the quantity decoupling index. Based on empirical results, the study puts forward some policies to promote the efficient carbon decoupling of the industrial economy.

Arginine-rich dipeptide repeat proteins (R-DPRs), abnormal translational products of a GGGGCC hexanucleotide repeat expansion in

In order to give guidance to improve tourism competitiveness and sustainable development, it is particularly important to identify and analyze the factors and mechanisms that affect efficiency. The SBM–DEA model including undesirable outputs was used to measure the tourism efficiency of 30 provinces in China from 2006 to 2019. Combined with the compound DEA model, the sensitivity of each province to the fluctuation of the input–output index was mined. The exploratory spatial analysis method and fixed effect model were used to analyze the spatial change and driving factors of tourism efficiency. The results show that: (1) the tourism efficiency of each province in China fluctuated from 2006 to 2019, and the average value was raised from 0.12 to 0.71, generally reaching the grade of medium and high efficiency; (2) the spatial difference of tourism efficiency is significant, but there is no obvious spatial correlation; (3) the most important input factors to tourism efficiency are environmental resources, tourism resource inputs and tourism infrastructure construction, and tourism fixed asset investment is redundant. (4) Optimizing the industrial structure, strengthening the introduction of core technology, and continuously promoting the process of urbanization and marketization are important ways to improve the efficiency of tourism.

Colorectal carcinoma (CRC) is one of the most frequently encountered neoplasms with high morbidity and mortality. Activation of the programmed death protein 1/programmed death ligand 1 (PD-1/PD-L1) signaling pathway results in tumor immune evasion by suppressing the activity of T cells. The correlation of PD-L1 with clinicopathological features, lymph node metastasis, diagnosis and prognosis is less clear in CRC. The aim of present work was to investigate the diagnostic and prognostic value of PD-L1, and the association of PD-L1 with clinicopathological features in CRC patients. Three hundred and eighty-six patients were included in this study. The soluble PD-L1 (sPD-L1) in Serum was measured by ELISA, and PD-L1 on tumor cells was evaluated by immunohistochemistry. Pretreatment levels of sPD-L1 were significantly elevated in CRC patient sera compared to healthy donors (P p p > 0.05). Meanwhile, univariate analysis indicated that the PD-L1 expression on tumor cells, tumor differentiation, and lymph node metastasis were statistically associated with the prognosis of CRC patient (all p

Following the emergence of new morphology geogrids, tensile tests on some of the new morphology geogrids were conducted in this paper for practical engineering options. The study focuses on the tensile testing of 3D printed geogrids to analyze the effects of morphology differences (material, planar structure, filling rate, rib width and rib height) on the tensile properties of geogrids. The test results show that the tensile properties of high density polyethylene geogrids are stronger than those of polylactic acid geogrids. Increasing the filling rate of geogrid can increase the tensile performance while decreasing the rate of tensile performance improvement. In contrast to the elongation at the break of the geogrid, the maximum tensile strength and the maximum tensile modulus increase in the order of bidirectional, triaxial and quadaxial geogrids. When the rib width and the rib height increase by the same amount, the rib height increases the maximum tensile strength of the geogrid more than that of the rib width.

In this paper, a model of the composite foundation reinforced with geosynthetic encased stone columns was established using the discrete element method, and the characteristics of its action under cyclic loading were studied. The influence of the length and radius of the pile on the settlement of the composite foundation is analyzed. The deformation characteristics of the pile and the stress ratio of pile-soil are studied under different pile lengths and radius. Then, based on this, the analysis of the lateral deformation characteristics of the piles under cyclic loading, the calculation model of the geosynthetic encased pile composite foundation is established. The settlement calculation formula of the composite foundation is solved according to the deformation coordination relationship between the pile and soil, the equilibrium condition, and the boundary condition. The results show that the theoretical value is in good agreement with the simulation value, which verifies the rationality of the theoretical calculation formula.

Wood vinegar (WV) is a common agricultural additive used for treatment of soil and stimulation of plant growth. Phosphate rock powder (PR), coal fly ash (CFA), zeolite (ZE) and bentonite (BE) are the common adsorbents for heavy (loid) metals (HMLs)-contaminated soil treatment. The present study focused on the effect of desorption of Pb(II), Cd(II) and As(III) from adsorbents in the presence of WV. The experimental results revealed that the removal fractions of HMLs from adsorbents gradually decreased and then remained steady with the increase of dilution ratios of WV. Subsequently, the optimal additive concentration of WV on different adsorbents was obtained. The experiment results revealed that acetic acid was the dominating component in WV affecting adsorption capacities of adsorbents for HMLs. Moreover, the research took the first time to discover that the addition of WV effectively modified the structure of adsorbents to improve adsorption capacities for HMLs. Given the advantages of low cost and green products of WV, this study not only provided an effective guidance for rational management of agricultural and environmental safety, but paved a new path to modify the structure of adsorbents for better adsorption capacities for HMLs via addition of WV.

Based on the Sustainable Development Goals and competitiveness index, an evaluation index system for sustainable development of tourism cities was established. The sustainable development level of 221 outstanding tourism cities in 2018 was evaluated, and their sustainable development paths were designed accordingly. The results show the following: (1) There is a large gap in sustainable development scores. In general, no city has achieved a strong sustainable development model. Natural and cultural resources and protection systems are the shortcomings of the systems. (2) The weights of natural and cultural resources and protection systems are the largest, and the weights of natural and cultural resources endowment, degree of tourism infrastructure construction, and economic support for natural and cultural resources are larger. Nature reserve coverage index, network popularity, and other indicators have greater weight. (3) There is a gap in the sustainable development level of tourism cities in the eight comprehensive economic zones. The economic zones in the eastern and southern coastal areas are better than those in the northwest and the middle reaches of the Yellow River. (4) The driving factors of the eight types of tourism cities distinguished by their characteristics are basically the same, but the obstacles are different.

Manipulation in a densely cluttered environment creates complex challenges in perception to close the control loop, many of which are due to the sophisticated physical interaction between the environment and the manipulator. Drawing from biological sensory-motor control, to handle the task in such a scenario, tactile sensing can be used to provide an additional dimension of the rich contact information from the interaction for decision making and action selection to manoeuvre towards a target. In this paper, a new tactile-based motion planning and control framework based on bioinspiration is proposed and developed for a robot manipulator to manoeuvre in a cluttered environment. An iterative two-stage machine learning approach is used in this framework: an autoencoder is used to extract important cues from tactile sensory readings while a reinforcement learning technique is used to generate optimal motion sequence to efficiently reach the given target. The framework is implemented on a KUKA LBR iiwa robot mounted with a SynTouch BioTac tactile sensor and tested with real-life experiments. The results show that the system is able to move the end-effector through the cluttered environment to reach the target effectively.

Zeolite has traditionally been used to remediate wastewater and soil. The present study shows a new method for natural zeolite (NZ) modification with wood vinegar (WV). The optimal conditions for NZ modification with WV were determined, and the adsorption capacities towards lead (Pb), cadmium (Cd) and arsenic (As), antimicrobial activities against Escherichia coli, heavy metal(loid) fraction and characterizations of selected modified zeolites (MZs) were also investigated. The results indicate that 50-fold dilution of WV, 5 g of NZ dosage, 105 °C of drying temperature, 4 h and 95 °C of water bath are preferred for NZ modification with WV. The WV+NaOH-MZ exhibited the best performance in heavy metal removal and the most powerful antimicrobial activity among all the zeolites. The sequence of WV+NaOH-MZ for the maximum single metal(loid) adsorption capacities was Pb (48.67 mg/g) >Cd (23.67 mg/g) > As (0.024 mg/g). The WV+NaOH and WV modifications also can increase the stabilities of heavy metals in the MZs. The residual fractions of single Pb and Cd in WV+NaOH-MZ and WV-MZ were 50%, 55%, 34% and 30%, respectively. The pore size of WV+NaOH-MZ (11.73 nm) was bigger than that of NZ or WV-MZ. Additionally, the proportion of clinoptilolite in WV+NaOH-MZ was also higher than other zeolites. The surfaces of WV+alkali-MZs were rougher than that of NZ. Considering the low cost and environmental risk of WV, this work provides some useful information for management of agricultural and industrial residues, environment and food safety.

This paper presents the disturbance observers-based distributed formation control for multiple quadrotor aircrafts with external disturbances and uncertain parameters using multi-agent theory and finite-time control method. Firstly, the finite-time disturbance observers are proposed to handle the external disturbances on the position-loop. Similarly, when there are both the uncertain parameters and external disturbances on the attitude-loop, the finite-time disturbance observers are designed to estimate the total lump disturbances. By skillfully using homogeneous system theory, Lyapunov theory, and multi-agent theory, the distributed formation control algorithms are developed. Finally, through simulations, the efficiency of the proposed method (including the convergence rate and disturbance rejection) is verified.

Three sustainable development sub-indicators were established along with 49 indicators of sustainable development at the provincial level. We collected data for the key years of 2010, 2015, and 2018 and evaluated the sustainable development level of 31 provinces in China by using the best and worst value improved equal-weight TOPSIS method. With spatial autocorrelation and hotspot analysis, the spatial characteristics of the sustainable development level were studied. Grey correlation analysis and the offset degree index were also used to find out which indicators should be of most concern to improve the level of sustainable development. The results showed the following. (1) The level of sustainable development of China’s provinces is increasing, but there is a decrease from east to west. (2) In terms of sustainable development, the gap between the four major economic regions is narrowing. (3) The overall sustainable development level is highly consistent with the mainstream green development and the human development index, indicating that exploiting the driving force behind developing and improving the quality of development is the key to China’s sustainable development strategy. (4) Different measures should be taken to promote the realization of Sustainable Development Goals in different areas.

Microexpression is usually characterized by short duration and small action range, and the existing general expression recognition algorithms do not work well for microexpression. As a feature extraction method, non-negative matrix factorization can decompose the original data into different components, which has been successfully applied to facial recognition. In this paper, local non-negative matrix factorization is explored to decompose microexpression into some facial muscle actions, and extract features for recognition based on apex frame. However, the existing microexpression datasets fall short of samples to train a classifier with good generalization. The macro-to-micro algorithm based on singular value decomposition can augment the number of microexpressions, but it cannot meet non-negative properties of feature vectors. To address these problems, we propose an improved macro-to-micro algorithm to augment microexpression samples by manipulating the macroexpression data based on local non-negative matrix factorization. Finally, several experiments are conducted to verify the effectiveness of the proposed scheme, which results show that it has a higher recognition accuracy for microexpression compared with the related algorithms based on CK+/CASME2/SAMM datasets.

Robotic systems are increasingly required not only to generate precise motions to complete their tasks but also to handle the interactions with the environment or human. Significantly, soft interaction brings great challenges on the force control due to the nonlinear, viscoelastic and inhomogeneous properties of the soft environment. In this paper, a robust impedance control scheme utilizing integral backstepping technology and integral terminal sliding mode control is proposed to achieve force tracking for an ultrasonic motor-actuated end-effector in a soft environment. In particular, the steady-state performance of the target impedance while in contact with soft environment is derived and analyzed with the nonlinear Hunt-Crossley model. Finally, the dynamic force tracking performance of the proposed control scheme is verified via several experiments.

Ever since a GGGGCC hexanucleotide repeat expansion mutation in C9ORF72 was identified as the most common cause of familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), three competing but nonexclusive hypotheses to explain how this mutation causes diseases have been proposed and are still under debate. Recent studies in the field have tried to understand how the repeat expansion disrupts cellular physiology, which has suggested interesting convergence of these hypotheses on downstream, functional defects in cells, such as nucleocytoplasmic transport disruption, membrane-less organelle defects, and DNA damage. These studies have not only provided an integrated view of the disease mechanism but also revealed novel cell biology implicated in neurodegeneration. Furthermore, some of the discoveries have given rise to new ideas for therapeutic development. Here, we review the research progress on cellular pathophysiology of C9ORF72-mediated ALS and FTD and its therapeutic implication. We suggest that the repeat expansion drives pathogenesis through a combination of downstream defects, of which some can be therapeutic targets.

Ever since a GGGGCC hexanucleotide repeat expansion mutation in C9ORF72 was identified as the most common cause of familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), three competing but nonexclusive hypotheses to explain how this mutation causes diseases have been proposed and are still under debate. Recent studies in the field have tried to understand how the repeat expansion disrupts cellular physiology, which has suggested interesting convergence of these hypotheses on downstream, functional defects in cells, such as nucleocytoplasmic transport disruption, membrane-less organelle defects, and DNA damage. These studies have not only provided an integrated view of the disease mechanism but also revealed novel cell biology implicated in neurodegeneration. Furthermore, some of the discoveries have given rise to new ideas for therapeutic development. Here, we review the research progress on cellular pathophysiology of C9ORF72-mediated ALS and FTD and its therapeutic implication. We suggest that the repeat expansion drives pathogenesis through a combination of downstream defects, of which some can be therapeutic targets.

As a new type of soft ground treatment technology, the geosynthetic-encased stone column (GESC) has been extensively used in engineering of roads and highways. In order to investigate the bearing mechanism of GESCs under cyclic loading, a series of experiments and numerical simulations were carried out using the proportional model. This paper described these changes in settlement and pile-soil stress ratio with emphasis on the ratio of length to diameter and the strength of wrapping material. Under the background of model test, a GESC reinforced composite foundation was simulated by the particle flow method. The reliability of the numerical simulation results was verified by the test results. The results demonstrate that GESC can effectively reduce the settlement of composite foundation. As the ratio of length to diameter and the strength of the wrapping material increase, this reduction is more significant. The GESC can effectively decrease the soil stress in composite foundation. The simulation results show the behavior of load transfer and expansion in GESC reinforced composite foundation. The displacement vector of soil particles in composite foundation shows that the failure mode of soil is shear failure. As the number of cycles increases, the range of failure surface expands.

In order to enable the interaction between human and mobile robot, a control platform of mobile robot is designed using speech recognition and robot operation system (ROS). The PC installed with ROS performs as server to communicate with the mobile robot which acts as client through WIFI. The server sends commands generated from the speech recognition to the client to control the motion of mobile robot. Simultaneously, the mobile robot transfers information to the sever, and the visualization tool called RVIZ is used to display the motion trajectory and tilt angle of the robot in real-time. The simulation and experimental results demonstrate that the platform can play an important role on human-robot interaction research field and provides potential engineering application and promotion significance.

To reduce the high mortality rate from cardiovascular disease (CVD), the electrocardiogram (ECG) beat plays a significant role in computer-aided arrhythmia diagnosis systems. However, the complex variations and imbalance of ECG beats make this a challenging issue. Since ECG beat data exist in heavily imbalanced category, an effective long short-term memory (LSTM) recurrence network model with focal loss (FL) is proposed. For this purpose, the LSTM network can disentangle the timing features in complex ECG signals, while the FL is used to resolve the category imbalance by downweighting easily identified normal ECG examples. The advantages of the proposed network have been verified in the MIT-BIH arrhythmia database. Experimental results show that the LSTM network with FL achieved a reliable solution to the problem of imbalanced datasets in ECG beat classification and was not sensitive to quality of ECG signals. The proposed method can be deployed in telemedicine scenarios to assist cardiologists into more accurately and objectively diagnosing ECG signals.

This paper mainly studies the formation control problem of multiple quadrotor aircraft via fixed-time control theory. First, based on the bilimit homogeneous theory and the framework of multiagent theory, for multiaircraft, a fixed-time formation control strategy is proposed. Considering the external disturbance existing on the attitude loop of the aircraft, the corresponding fixed-time disturbance observer is designed with the observer technology. Then, a fixed-time attitude controller is designed based on the accurate observation and fast compensation from the disturbance observer. Finally, some simulations are performed to verify the effectiveness of the proposed theoretical method.