Fault Detection in Power Distribution Networks Based on Comprehensive-YOLOv5.

Real-time fault detection in power distribution networks has become a popular issue in current power systems. However, the low power and computational capabilities of edge devices often fail to meet the requirements of real-time detection. To overcome these challenges, this paper proposes a lightweight algorithm, named Comprehensive-YOLOv5, for identifying defects in distribution networks. The proposed method focuses on achieving rapid localization and accurate identification of three common defects: insulator without loop, cable detachment from the insulator, and cable detachment from the spacer. Based on the You Only Look Once version 5 (YOLOv5) algorithm, this paper adopts GhostNet to reconstruct the original backbone of YOLOv5; introduces Bidirectional Feature Pyramid Network (BiFPN) structure to replace Path Aggregation Network (PANet) for feature fusion, which enhances the feature fusion ability; and replaces Generalized Intersection over Union GIOU with Focal Extended Intersection over Union (Focal-EIOU) to optimize the loss function, which improves the mean average precision and speed of the algorithm. The effectiveness of the improved Comprehensive-YOLOv5 algorithm is verified through a "morphological experiment", while an "algorithm comparison experiment" confirms its superiority over other algorithms. Compared with the original YOLOv5, the Comprehensive-YOLOv5 algorithm improves mean average precision (mAP) from 88.3% to 90.1% and increases Frames per second (FPS) from 20 to 52 frames. This improvement significantly reduces false positives and false negatives in defect detection. Consequently, the proposed algorithm enhances detection speed and improves inspection efficiency, providing a viable solution for real-time detection and deployment at the edge of power distribution networks.

Engineering of a newly isolated Bacillus tequilensis BL01 for poly-γ-glutamic acid production from citric acid.

BACKGROUND: Poly γ-glutamic acid (γ-PGA) is a promising biopolymer for various applications. For glutamic acid-independent strains, the titer of γ-PGA is too low to meet the industrial demand. In this study, we isolated a novel γ-PGA-producing strain, Bacillus tequilensis BL01, and multiple genetic engineering strategies were implemented to improve γ-PGA production. RESULTS: First, the one-factor-at-a-time method was used to investigate the influence of carbon and nitrogen sources and temperature on γ-PGA production. The optimal sources of carbon and nitrogen were sucrose and (NH4)2SO4 at 37 °C, respectively. Second, the sucA, gudB, pgdS, and ggt genes were knocked out simultaneously, which increased the titer of γ-PGA by 1.75 times. Then, the titer of γ-PGA increased to 18.0 ± 0.3 g/L by co-overexpression of the citZ and pyk genes in the mutant strain. Furthermore, the γ-PGA titer reached 25.3 ± 0.8 g/L with a productivity of 0.84 g/L/h and a yield of 1.50 g of γ-PGA/g of citric acid in fed-batch fermentation. It should be noted that this study enables the synthesis of low (1.84 × 105 Da) and high (2.06 × 106 Da) molecular weight of γ-PGA by BL01 and the engineering strain. CONCLUSION: The application of recently published strategies to successfully improve γ-PGA production for the new strain B. tequilensis BL01 is reported. The titer of γ-PGA increased 2.17-fold and 1.32-fold compared with that of the wild type strain in the flask and 5 L fermenter. The strain shows excellent promise as a γ-PGA producer compared with previous studies. Meanwhile, different molecular weights of γ-PGA were obtained, enhancing the scope of application in industry.

Tyrosinase-Modified UHMW SELP Polymers as Wet and Underwater Adhesives to Achieve Multi-interface Adhesion.

The presence of a hydration layer in humid and underwater environments challenges adhesive-substrate interactions and prevents effective bonding, which has become a significant obstacle to the development of adhesives in the industrial and biomedical fields. In this study, ultrahigh-molecular-weight (UHMW) silk-elastin-like proteins (SELP) with 3,4-dihydroxyphenylalanine (DOPA) converted from tyrosine residues by tyrosinase exhibited excellent adhesive properties on different interfaces, such as glass, aluminum, wood, polypropylene sheets, and pigskin, under both dry and wet conditions. Additionally, by incorporating trace amounts of cross-linking agents like Fe3+, NaIO4, and tris(hydroxymethyl) phosphine (THP), the mussel-inspired adhesives maintained a stable and excellent adhesion, broadening the conditions of application. Notably, the UHMW SELP adhesive exhibited remarkable underwater adhesion properties with a shear strength of 0.83 ± 0.17 MPa on glass. It also demonstrated good adhesion to biological tissues including the kidney, liver, heart, and lungs. In vitro cytocompatibility testing using L929 cells showed minimal toxicity, highlighting its potential application in the biomedical field. The sustainable, cytocompatible, cost-effective, and highly efficient adhesive provides valuable insights for the design and development of a new protein-based underwater adhesive for medical application.

Regulation of Drosophila circadian rhythms by miRNA let-7 is mediated by a regulatory cycle.

MicroRNA-mediated post-transcriptional regulations are increasingly recognized as important components of the circadian rhythm. Here we identify microRNA let-7, part of the Drosophila let-7-Complex, as a regulator of circadian rhythms mediated by a circadian regulatory cycle. Overexpression of let-7 in clock neurons lengthens circadian period and its deletion attenuates the morning activity peak as well as molecular oscillation. Let-7 regulates the circadian rhythm via repression of CLOCKWORK ORANGE (CWO). Conversely, upregulated cwo in cwo-expressing cells can rescue the phenotype of let-7-Complex overexpression. Moreover, circadian prothoracicotropic hormone (PTTH) and CLOCK-regulated 20-OH ecdysteroid signalling contribute to the circadian expression of let-7 through the 20-OH ecdysteroid receptor. Thus, we find a regulatory cycle involving PTTH, a direct target of CLOCK, and PTTH-driven miRNA let-7.