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Robotic manipulators usually exhibit time‐varying, nonlinear, and coupled dynamics due to the parameter perturbations, disturbances, and other uncertainties. Traditional control algorithms typically do not possess parameters' self‐adaptive learning ability, limiting the tracking performance of the robot. In order to address these issues, an adaptive sliding mode control method based on reinforcement learning (ASMRL) is proposed in this paper, where a proportional–integral sliding mode (PISM) controller is used to address the nonlinear problem in the system, and deep deterministic policy gradient (DDPG) agent is adopted to conduct the parameters' learning of the PISM controller using its adaptive characteristics and the autonomous learning ability. The simulation results illustrate that the proposed method can effectively achieve better tracking performance compared with two other control methods, demonstrating the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Hybridly polarized (HP) vector vortex Raman lasers dramatically extend their applications on optical microscopy, optical communication, and quantum information. Spatial light modulators and waveplates are widely used for generating HP vector vortex lasers, however, the performance and beam quality of HP vector vortex lasers are restricted by diffraction loss and low damage threshold of these optical elements. Here, HP vector vortex Raman microchip lasers constructed with Yb3+:Y3Al5O12 (Yb:YAG) and vanadate (YVO4) crystals is demonstrated. The states of polarization (SoP) of HP vector vortex lasers are combination of radial and anti‐radial polarizations (RP‐ARP), azimuthal and anti‐azimuthal polarizations (AP‐AAP). The SoP of HP vector vortex lasers can be controlled by adjusting the length of YVO4 crystal and applying pump power. Maximum output powers are 456 and 586 mW with optical efficiency of 7.1% and 9.2% for HP vector vortex lasers with SoP of RP‐ARP and AP‐AAP. The HP vector vortex Raman lasers with SoP of RP‐ARP and AP‐AAP oscillate ≈1076 nm with bandwidths of 11.4 and 10.8 nm. High beam quality is achieved for HP vector vortex lasers with measured M2 nearly equal to theoretical value. The broadband HP vector vortex Raman lasers with high beam quality extend applications on optical trapping, and quantum information processing. [ABSTRACT FROM AUTHOR]

Many restaurants have a certain amount of food waste. The monitoring of food waste will help restaurants to eliminate some dishes with outrageous waste and reduce waste from the source. In view of this, this research proposed a method to detect waste of dishes through image processing and deep learning technology. According to the remaining quantity of the dishes, the collected dish images were preliminarily divided into six levels, which were used as sample labels, and then the image of the uneaten dishes and the image of the dishes after eating were stacked as the input of the network. Trained in the InceptionV3, Xception, and ResNet18 network models, we find that compared with the single image data as the input, the effect of stacking the two images data as the input was better. The accuracy of sample label recognition increased by 6.97%, 5.81%, and 4.1% respectively. Further analysis discovered that the sample that predicted wrong on the test set data, its true label, and the predicted wrong label were adjacent. Therefore, with the help of the probability vector output by the trained network model, the definition method of the level of dish waste degree and its corresponding accuracy metric standard was further given. Finally, the recognition accuracy of the best network structure InceptionV3 on the test set data can reach 98.47%. [ABSTRACT FROM AUTHOR]

[Display omitted] Preventing breast cancer liver metastasis presents formidable challenges with multifaceted obstacles. In the case of acute and chronic liver injury, the disrupted liver microenvironment induced by activated hepatic stellate cells (aHSCs) would suppress immune surveillance and license the re-multiplication of disseminated tumor cells (DTCs). Herein, a cyclic peptide pPB modified nanovesicle with aHSCs targeting capability was constructed as CP-SB-siRNA to co-deliver hydrophobic SB431542 and nucleic acid drug CXCL12 siRNA. Due to the TGF-β signaling inhibition of SB431542, CP-SB-siRNA significantly suppressed the expression levels of genes coding the uppermost fibrosis-associated proteins including α-sma , Col-1 and Col-3 in aHSCs. On the other hand, the gene and protein expression level of metastasis-associated chemokine CXCL12 was significantly decreased. In addition, CP-SB-siRNA could regain the function of NK cells and attenuate the breast cancer proliferation through CXCL12-CXCR4 axis. On both breast cancer spontaneous metastasis with fibrosis mouse model and breast cancer via hematogenous metastasis with fibrosis mouse model, CP-SB-siRNA successfully reversed hepatic fibrosis by regressing aHSCs, and thereby restored the liver microenvironment, ultimately inhibiting breast cancer hepatic metastasis. This nanomaterial vector, featuring targeting and drug co-delivery functionalities, exhibited a great potential to restrain breast cancer hepatic metastasis based on the relationship among aHSCs, NK cells and DTCs. [ABSTRACT FROM AUTHOR]

An organic-inorganic hybrid polyoxometalate (POM) based on bi-nuclear copper complexes and Dawson-type phosphotungstate (POT) [CuL(H2O)][CuL]2[P2W18O62]·3H2O (abbreviated as CPW) (L = 2-(1H-pyrazol-3-yl)pyridine) was synthesized and structurally characterized by IR spectrum, and single-crystal X-ray diffraction. Structural analysis indicated that CPW is nanoscale molecule and extends into a two-dimensional layer, in which three bi-nuclear copper complexes are substituted at different sites of Dawson-type POT and joined adjacent POT fragments together. Notably, CPW can efficiently catalyze the production of reactive oxygen species. [ABSTRACT FROM AUTHOR]