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Human-robot-collaboration requires robot to proactively and intelligently recognize the intention of human operator. Despite deep learning approaches have achieved certain results in performing feature learning and long-term temporal dependencies modeling, the motion prediction is still not desirable enough, which unavoidably compromises the accomplishment of tasks. Therefore, a hybrid recurrent neural network architecture is proposed for intention recognition to conduct the assembly tasks cooperatively. Specifically, the improved LSTM (ILSTM) and improved Bi-LSTM (IBi-LSTM) networks are first explored with state activation function and gate activation function to improve the network performance. The employment of the IBi-LSTM unit in the first layers of the hybrid architecture helps to learn the features effectively and fully from complex sequential data, and the LSTM-based cell in the last layer contributes to capturing the forward dependency. This hybrid network architecture can improve the prediction performance of intention recognition effectively. One experimental platform with the UR5 collaborative robot and human motion capture device is set up to test the performance of the proposed method. One filter, that is, the quartile-based amplitude limiting algorithm in sliding window, is designed to deal with the abnormal data of the spatiotemporal data, and thus, to improve the accuracy of network training and testing. The experimental results show that the hybrid network can predict the motion of human operator more precisely in collaborative workspace, compared with some representative deep learning methods.

An alternative biosynthetic route to form the furan-fused chromene skeleton in xyloketals is proposed, which involves coupling of two moieties from a bifurcated polyketide pathway, instead of the previously proposed polyketide–terpenoid pathway.

This review presents the recent progress on the oxygen-generating biocatalytic nanomaterials for relieving tumor hypoxia in cancer radiotherapy.

Interactions and dynamics are critical mechanisms for multi-agent systems to achieve complex intelligence through the cooperation of simple agents. Yet, inferring interactions of the multi-agent system is still a common and open problem. A new method named K-similarity is designed to measure the global relative similarities for inferring the interactions among multiple agents in this paper. K-similarity is defined to be a synthetic measure of relative similarity on each observation snapshot where regular distances are nonlinearly mapped into a network. Therefore, K-similarity contains the global relative similarity information, and the interaction topology can be inferred from the similarity matrix. It has the potential to transform into distance strictly and detect multi-scale information with various K strategies. Therefore, K-similarity can be flexibly applied to various synchronized dynamical systems with fixed, switching, and time-varying topologies. In the experiments, K-similarity outperforms four benchmark methods in accuracy in most scenarios on both simulated and real datasets, and shows strong stability towards outliers. Furthermore, according to the property of K-similarity we develop a Gaussian Mixture Model (GMM)-based threshold to select probable interactions. Our method contributes to not only similarity measurement in multi-agent systems, but also other global similarity measurement problems.

Mesenchymal stem cells (MSCs) can treat myocardial injury–related diseases by differentiating into cardiomyocytes. Islet-1 plays an essential role in cardiac maturation. We have discovered that Islet-1 plays a crucial role in the histone acetylation regulation in this process. In addition, to increase GATA4/Nkx2.5 expression, Islet-1 may bind to Gcn5 and then guide Gcn5 to the GATA4/Nkx2.5 promoters, thereby facilitating the differentiation of MSCs into cardiomyocytes. Islet-1 is an important factor in the maturation of the heart. We have previously found that the pivotal factor in histone acetylation regulation in this process is Islet-1. Furthermore, Islet-1 and Gcn5 may boost GATA4/Nkx2.5 expression, which in turn promotes cardiomyocyte differentiation from MSCs. But the molecular mechanism of Islet-1 binding to GCN5 has not been elucidated. In this study, we found that the competitive binding relationship between Islet-1 and MLIP and GCN5 affected myocardial differentiation. The key enzymes of ubiquitination modification of MLIP and Islet-1 are UBE3C and WWP1, respectively. When short hairpin RNA (shRNA) was used to inhibit β-catenin expression, we found that the expression of UBE3C was upregulated, modifying MLIP ubiquitination and reducing its expression, and it upregulated Islet-1 by inhibiting the expression of WWP1. By using the chromatin immunoprecipitation (ChIP) and luciferase reporter system, we found that when MLIP binds to Islet-1, it significantly inhibits the transcriptional activity of Islet-1. In summary, our results show that decreasing β-catenin regulates the ubiquitination of Islet-1 and MLIP, affecting their expression, reducing the amount of Islet-1 binding to MLIP, and increasing the amount of binding to GCN5 in the nucleus. Therefore, the transcriptional activity of Islet-1 is significantly activated, inducing C3H10T1/2 cells to differentiate into myocytes. Further knowledge of biochemical pathways, including molecular signaling pathways, can provide more insights into the myocardial differentiation mechanism of MSCs.

The open-air burning of the massive generated crop straw in rural areas has been a troubling problem in China in recent decades, and the utilization and valorization of crop straw have provided promising solutions to it. However, due to the limitations in straw resources, economic, social, and technological conditions, different regions vary greatly with each other in the technological pathways and performance of straw utilization. By taking ten counties and districts of Xinyang City in Henan Province of China as examples, it analyzed the spatial distribution of straw yields and the adoption of five pathways of crop straw utilization in Xinyang City, and summarized three typical combination modes. In addition, it also provided the integrated model of FBWM-TOPSIS-PROMETHEE to evaluate the performance of crop straw utilization in the ten counties and districts, to provide local decision-makers with the pathways for promoting the utilization and valorization of crop straw. The results indicated that: (1) The endowment of straw resources and the straw utilization pathways in the ten counties and districts of Xinyang City vary greatly with each other; (2) Returning crop straw to the fields as fertilizer after being crushed is the mainstream mode of resource utilization of crop straw, although five technological modes have been adopted in Xinyang City; (3) Among the 10 counties, Huaibin and Xixian have the best performance of resource utilization of crop straw, and Shangcheng is the worst performer.

The synthesis of aryl iodides from commercially available raw chemicals by simple, cheap and green strategies is of fundamental significance. Aryl iodides can undergo a series of homo-/cross-coupling reactions for the synthesis of important industrial chemicals and materials. Traditional methods require the electrophilic substitution on aromatic compounds by iodine or hypervalent iodine compounds, which suffers from the use of erosive halogens or hazardous oxidants. With the development of green chemistry in the field of electrochemical synthesis, anodic oxidation-derived I+ cations have been used for substitution reactions. However, the selectivity of the iodination by these electrochemical methods remains unsatisfactory. We believed that the anolyte is contaminated by trace platinum species from the working electrode. Herein, we report the generation of active I+ species from the anodic oxidation of I2 in acetonitrile using a glassy carbon electrode. With the presence of H+, electrolyte prepared with a glassy carbon anode can react with anisole to selectively form 4-iodoanisole with a yield as high as 97%. On contrast, the electrolytes prepared from Pt and graphite anodes finished the reaction with yields of 16% and 60% for 4-iodoanisole, respectively. This electrochemical method also applies to the iodination of toluene, benzonitrile and bromobenzene, delivering the target para-iodination products with 92%, 84%, and 73% yields, respectively. Thus, an atom-efficient and highly selective aryl iodination method was developed without the use of excessive oxidants.

The Beijing genotype is the most common type of tuberculosis in Jiangxi Province, China. The association of population characteristics and their prevalence in the development of recent transmission is still unclear. 1,433 isolates were subjected to drug-resistant tests and MIRU-VNTR analysis. We compared differences in demographic characteristics and drug resistance patterns between the Beijing and non-Beijing family strains. We also explored the association of the clustering rate with the Beijing genotype of Mycobacterium tuberculosis. The Beijing genotype was dominant (78.16%). The results of MIRU-VNTR showed that 775 of 1,433 strains have unique patterns, and the remaining gather into 103 clusters. A recent transmission rate was 31.54% (452/1,433). The Beijing genotype strains were more likely to spread among the recurrent population (p = 0.004), people less than 50 years of age (p = 0.02 or 0.003), and the personnel in the northern regions (p = 0.03). Drug resistance patterns did not show significant differences between Beijing and non-Beijing genotype isolates. Furthermore, we found that HIV-positive cases had a lower clustering rate (p = 0.001). Our results indicated that the recurrent population and people under 50 years of age were more likely to be infected with the Beijing genotype of M. tuberculosis. The strains from the Beijing family were easier to cluster compared to strains isolated from the non-Beijing family. Social activity and AIDS substantially impacted the clustering rate of the Beijing genotype of M. tuberculosis. Multidrug resistant M. tuberculosis affected Beijing genotype transmission.

We examine the relationship between high-performance work system (HPWS) and job satisfaction, drawing on the ‘too much of a good thing’ theory, to establish whether a non-linear relationship can explain conflicts in previous findings. Moreover, we extend the study by exploring the mediating role of work overload and the moderating role of person–organization fit (P–O fit). Based on a cross-sectional data set of 220 employees and a longitudinal data set of 373 employees from organizations in China, the empirical findings show an invertedU-shaped relationship between HPWS and job satisfaction. Results also indicate that the relationship between HPWS and job satisfaction is fully mediated by work overload, and that P–O fit negatively moderates HPWS-work overload and HPWS-job satisfaction relationships. These results shed new light on how HPWS impacts employee outcomes and practical implications for managers are discussed.

Different from the traditional noise control approaches based on sound energy reduction, this study focuses on the annoyance suppression of motor vehicle noise based on audio injection. Firstly, eight motor vehicle noises were selected as the target sounds and three different controllable sounds were used to overlap with different signal-to-noise ratios. Then absolute threshold and combined sound annoyance subjective evaluation experiment were carried out to obtain absolute threshold range and the existence zone of "destructive effect" for combined noise annoyance. Next the influencing factors of the destructive effect are analyzed. The results of the study found that the identifiability of the target sound and the controllable sound is important to the selection of the controllable sound. For most target sounds with high identifiability, the controllable sound with high identifiability and high SNR should be selected. For most target sounds with low identifiability, the controllable sound with low identifiability and low SNR should be selected. Moreover, after the addition of optimal controllable sound, the descend value of the annoyance degree of the target sound with high identifiability is lower than that of the target sound with low identifiability. The results will also provide guidance for the research on audio injection effects, physical mechanisms, the controllable sound selection and optimization design.

High-frequency electromagnetic linear machine is one major component for linear eletro-hydraulic actuator that in turn is extrimely important for the flight control of more-electrical or all-electrical aircrafts. The employment of high-frequency linear machine helps to achieve high reliability and dynamic performance of the actuators. However, the capability of heat dissipation of the linear machine unavoidably constrains the input current, which in turn depresses its output performance. Therefore, this paper proposes a novel electromagnetic linear machine based on the self-powered direct oil-cooling windings. Specifically, the windings are immersed into the oil directly, which helps to decrease the temperature of the linear machine significantly and thus increase its output performance. In addition, the oil is pushed by the motion of the mover itself. No additional pump is required. The design concept of high-frequency electromagnetic linear machine along with its operating principle is presented. A high-precision three-dimensional (3D) piecewise modeling method is proposed to simultaneously consider axial, radial and circumferential equivalent thermal circuits. Numerical simulation is conduced to validated the analytical model. A research prototype of the machine based on direct oil-cooling windings is developed and empolyed for experimental study, and the experimental result verifies the mathematical model of the thermal field well.