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Plastic products are a significant component of the manufacturing industry and the plastic industry is closely related to economic and social development. As constraints from resources and environment tighten, rational disposal and utilization of waste plastics becomes crucial for the sustainable economic and environmental development. Currently, the variety of plastic products becomes abundant, and disposal technologies and application challenges are constantly updated. Considering the demand for highquality development of the industry and increasingly strict environmental protection requirements, a systematic analysis of the research progress of waste plastic disposal and utilization becomes urgent. In this study, the waste plastic disposal and utilization technologies are categorized into mechanical disposal of waste plastics, energy and resource conversion, regeneration recycling, and new technologies for disposal and utilization. These four types of technologies are expounded from the aspects of technical features, applicable conditions, and research progress. On the basis, facing the technical challenges and referring to the existing experience of developed countries, suggestions are proposed from the aspects of source reduction, sorted recycling of waste plastics, and technological innovation and transformation, hoping to provide a reference for the clean disposal and recycling of waste plastics in China.

Synthetic aperture radar (SAR) is a high-resolution imaging radar. With the deteriorating electromagnetic environment, SAR systems are susceptible to various forms of electromagnetic interference, including deception jamming. This jamming notably impacts SAR signal processing and subsequently worsens the quality of acquired images. Chaotic frequency modulation (CFM) signals could effectively counteract deception jamming. Nevertheless, due to the inadequate band-limited performance of CFM signals, higher oversampling factors are needed for achieving optimal low sidelobe levels, leading to increased system costs and excessively high data rates. Additionally, not all chaotic sentences meet the CFM signal requirements. In response, this paper proposes a novel signal modulation method called chaotic-nonlinear frequency modulation (C-NLFM) that enhances band-limited performance. The optimum parameters for C-NLFM signals are selected using the particle swarm optimization (PSO) algorithm. In this way, C-NLFM signals attain ideal low sidelobe levels even when faced with reduced oversampling factors. Meanwhile, this chaotic coding mode retains its capability to effectively suppress deception jamming. Moreover, C-NLFM signals demonstrate versatility in adapting to various chaotic sequences, thereby enhancing their flexibility to modify the signals as required. Through comprehensive simulations, data analysis, and a semi-physical experiment, the effectiveness and superiority of this proposed method have been confirmed. [ABSTRACT FROM AUTHOR]

In order to understand the effects of diamond coating on the milling performances of carbide micro-milling cutters with diameter of 50 µm, the micro-groove milling experiments of diamond coated and uncoated tools were carried out. Firstly, the D-shaped micro-milling cutter with diameter of 50 µm was prepared by using WEDG. Then, the micro-groove milling process experiments were carried out on pure copper workspaces with diamond coated and uncoated tools; Changes of the surface morphology and roughness of micro-grooves with milling distance were observed by white-light interferometer and ultra-depth-of-field microscope, and the effects of diamond coating on the milling processes of cemented carbide micro-milling cutters were analyzed. The results show that the micro-groove processed with diamond coating tools has less burr, the surface roughness value !s twice lower than that milled with uncoated tools, and stable groove width, roughness value and side morphology may maintain within a certain dsstance. [ABSTRACT FROM AUTHOR]

Introduction: Peroxiredoxin 6 (Prdx6) is widely expressed in mammalian tissues. Our previous study demonstrated that Prdx6 was expressed in human epididymis, present in human seminal fluid, and in spermatozoa. The protective role of Prdx6 in maintaining the viability and DNA integrity of human spermatozoa was also detected. Here, we demonstrate the potential role and mechanism of Prdx6 in human epididymis epithelial cells (HEECs)., Material and Methods: Western blotting was used to measure expression levels of key proteins in the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway. The malonaldehyde (MDA) levels and antioxidant capacity in HEECs were detected with the commercial kits. Digital gene expression analysis (DGE) was used to identify gene expression patterns in control and Prdx6-interference HEECs. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to validate the DGE findings., Results: Compared to control HEECs, the expression levels of JAK1, STAT1, phosphorylated JAK1 and STAT1 were significantly increased, while the expression level of SOCS3 was significantly decreased in Prdx6-interference HEECs. The MDA level and total antioxidant capacity in Prdx6-interference HEECs were significantly increased and decreased compared to that of control, respectively. DGE analysis identified 589 up-regulated and 314 down-regulated genes (including Prdx6) in Prdx6-interference HEECs. Thirteen significantly different pathways were identified between the two groups, with the majority of genes belonging to the CCL, CXCL, IL, and IFIT family of proteins and were related to immunity. In particular, the expression levels of IL6, IL6ST, and eighteen IFN-related genes were significantly increased in Prdx6-interference HEECs compared to control HEECs., Conclusions: We found that reduced Prdx6 expression induced higher ROS levels in HEECs, which resulted in the activation of the IL-6 receptor and IFNγ expression to induce the JAK1/STAT1 signaling pathway.