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This paper proposes an improved DeepLabV3+ lightweight algorithm for the identification of installation gaps in spacer replacement robots. By using lightweight MobileNetV3 to extract semantic features of spacer installation gaps, parameters and computational complexity are reduced; Perform dimensionality reduction and dimensionality increase operations on the ASPP module to reduce the number of model parameters; Introduce ECA module to restore the clarity of target boundaries; Use a loss function combining Focal Loss and Dice Loss to enhance segmentation performance. The experimental results show that the improved DeepLabV3+ algorithm improves MIoU, MPA, and prediction speed, while balancing segmentation accuracy and speed, and can effectively segment the installation gap of the spacer.

It is a developing trend for transmission line operation robots to replace manual operations in line operation and maintenance. However, the existing on-line methods of robots are complex and inefficient, which seriously affects the progress of the entire operation and maintenance. In order to solve this problem, this paper studies the automatic on-line and off-line control method of live working robot for 500kV transmission lines. Firstly, the on-line and off-line structure of the robot and its operating mechanism are analyzed, and on this basis, the relevant mathematical model is established. Through the analysis of the model, cascade fuzzy PID is used to control the robot’s attitude leveling. Finally, through MATLAB software simulation, the cascade fuzzy PID control effect is the best.

In this paper, four kinds of coatings Ni + 30% WC, Ni + 15% WC, Ni, and Co are prepared on EH40 steel by laser cladding technology. Electrochemical experiment tests at a simulating low-temperature (–40°C) environment in 0.5 mol·L−1 hydrochloric acid (HCl) solution and 3.5 wt% NaCl solution were conducted, and the polarization curve and electrochemical impedance spectroscopy (EIS) impedance spectrum were obtained. The results show that the Ni + 15% WC coating has the smallest corrosion current and 0.5 mol·L−1 HCl solution and 3.5 wt% NaCl solution have the maximum polarization resistance and impedance arc. Coatings will be treated in a 0.5 mol·L−1 HCl solution and 3.5 wt% NaCl solution at –40°C immersion for 30 days; finally, X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) were used for test passivation films of Ni + 15% WC samples and sample surface morphology after corrosion. XPS results show that Fe, Mo, and Ni elements can form metal oxides in the 0.5 mol·L−1 HCl solution, and Cr, Fe, Mo, Ni, and W elements can form metal oxides in the 3.5 wt% NaCl solution. SEM results display that relatively severe corrosion appeared on the substrate near tungsten carbide in a 0.5 mol·L−1 HCl solution, and coating will be corroded form inside of the coating owing to the corrosive solution will penetrate the substrate. In 3.5 wt% NaCl solution, severe corrosion of the substrate has not been observed; however, the binding part has been obviously corroded.

To investigate the corrosion behavior of WC–Co composite coating, plasma transferred arc (PTA) welding was applied to prepare WC–Co coating on hull steel EH40 for achieving good metallurgical bonding. The phases of coatings were mainly composed of WC particles, solid solution γ-Co, Fe3Ni2, SiO2 and Mo2C. After electrochemical test, it can be concluded that Co-based coating with 45% WC content has better corrosion resistance in low temperature marine environment for obtaining denser oxide film. Through X-ray photo electron spectroscopy (XPS) analysis, the main corrosion products of immersion were Co(OH)2 and Co3O4. These corrosion products aggregate to form a stable corrosion product film, which plays some protective role for the coating. Hard particle WC is also partially oxidized to WO3. The pitting hole of 60% WC is the most serious. Pitting corrosion is easy to occur at the interface defects.

Background: The TetR family of transcriptional regulators (TFRs), serving as crucial regulators of diverse cellular processes, undergo conformational changes induced by small-molecule ligands, which either inhibit or activate them to modulate target gene expression. Some ligands of TFRs in actinomycetes and their regulatory effects have been identified and studied; however, regulatory mechanisms of the TetR family in the lincomycin-producing Streptomyces lincolnensis remain poorly understood. Results: In this study, we found that AbrT (SLCG_1979), a TetR family regulator, plays a pivotal role in regulating lincomycin production and morphological development in S. lincolnensis. Deletion of abrT gene resulted in increased lincomycin A (Lin-A) production, but delayed mycelium formation and sporulation on solid media. AbrT directly or indirectly repressed the expression of lincomycin biosynthetic (lin) cluster genes and activated that of the morphological developmental genes amfC, whiB, and ftsZ. We demonstrated that AbrT bound to two motifs (5′-CGCGTACTCGTA-3′ and 5′-CGTACGATAGCT-3′) present in the bidirectional promoter between abrT and SLCG_1980 genes. This consequently repressed abrT itself and its adjacent gene SLCG_1980 that encodes an arabinose efflux permease. D-arabinose, not naturally occurring as L-arabinose, was identified as the effector molecule of AbrT, reducing its binding affinity to abrT-SLCG_1980 intergenic region. Furthermore, based on functional analysis of the AbrT homologue in Saccharopolyspora erythraea, we inferred that the TetR family regulator AbrT may play an important role in regulating secondary metabolism in actinomycetes. Conclusions: AbrT functions as a regulator for governing lincomycin production and morphological development of S. lincolnensis. Our findings demonstrated that D-arabinose acts as a ligand of AbrT to mediate the regulation of lincomycin biosynthesis in S. lincolnensis. Our findings provide novel insights into ligand-mediated regulation in antibiotic biosynthesis. [ABSTRACT FROM AUTHOR]

Ecological source areas play a pivotal role in nature preservation and soil conservation. These areas are critical in optimizing land-use patterns and fostering the establishment facilitating the establishment of protected ecological source areas. In this study, two types of state layers of ecological source area change were extracted based on land cover data and integrated with an intelligent algorithm to analyze the role of ecological factors contributing to land change. Recommendations are proposed to enhance the optimization of the ecological spatial pattern within the Yellow River Basin. The results indicate key findings: (1) The ecological source areas in the Daxia River Basin experienced Fluctuations between 1990 and 2020 due to the interconversion of grassland and unused land. The change was relatively smooth during 1990–2000, with the ecological source areas increasing slightly by 16.016 km2. From 2000 to 2010, the proportion of unutilized land transferred to grassland was 6.3%, which is significantly higher than the annual transfer average of 1.6%. This is mainly due to the ecological protection measures in the cities of Linxia and Hezuo. Between 2010 and 2020, economic construction resulted in the loss of grassland, and the percentage of grassland turned out was 7.3%, which was significantly higher than the annual average of 1.8%. (2) In the Daxia River Basin, rainfall, sunlight intensity, temperature, and elevation had a greater impact on land change during the period from 1990 to 2020, with contributions of −0.4, 0.09, 0.08, and −0.26, respectively. [ABSTRACT FROM AUTHOR]

The transcription factor (TF)‐mediated regulatory network controlling lincomycin production in Streptomyces lincolnensis is yet to be fully elucidated despite several types of associated TFs having been reported. SLCG_2919, a tetracycline repressor (TetR)‐type regulator, was the first TF to be characterized outside the lincomycin biosynthetic cluster to directly suppress the lincomycin biosynthesis in S. lincolnensis. In this study, improved genomic systematic evolution of ligands by exponential enrichment (gSELEX), an in vitro technique, was adopted to capture additional SLCG_2919‐targeted sequences harboring the promoter regions of SLCG_6675, SLCG_4123‐4124, SLCG_6579, and SLCG_0139‐0140. The four DNA fragments were confirmed by electrophoretic mobility shift assays (EMSAs). Reverse‐transcription quantitative polymerase chain reaction (RT‐qPCR) showed that the corresponding target genes SLCG_6675 (anthranilate synthase), SLCG_0139 (LysR family transcriptional regulator), SLCG_0140 (beta‐lactamase), SLCG_6579 (cytochrome P450), SLCG_4123 (bifunctional DNA primase/polymerase), and SLCG_4124 (magnesium or magnesium‐dependent protein phosphatase) in ΔSLCGL_2919 were differentially increased by 3.3‐, 4.2‐, 3.2‐, 2.5‐, 4.6‐, and 2.2‐fold relative to those in the parental strain S. lincolnensis LCGL. Furthermore, the individual inactivation of these target genes in LCGL reduced the lincomycin yield to varying degrees. This investigation expands on the known DNA targets of SLCG_2919 to control lincomycin production and lays the foundation for improving industrial lincomycin yields via genetic engineering of this regulatory network. [ABSTRACT FROM AUTHOR]

Byline: Tingting. Zhao, Bing. Chen, Yurong. Xu, Yiqing. Qu OBJECTIVE: Analysis of the occurrence factors and disease characteristics of tuberculous (TB) pleural effusion (TPE) dominated by neutrophils. METHODS: We retrospectively [...]

Byline: Tingting. Zhao, Yurong. Xu, Qian. Song, Xinjie. Wang, Minghua. Jin, Dianjie. Lin OBJECTIVE: The objective of this retrospective study was to assess the efficacy of medical thoracoscopy in diagnosing [...]