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Simple Summary: The wild population of Brachymystax tsinlingensis is a Grade II protected species in China. This population faces slow growth, harsh habitats, serious individual miniaturization, and a low survival rate of fry during its early developmental stage. To improve the aquaculture efficiency of this species, and thus increase the survival rate, protect species resources, and enrich species numbers, the present study was conducted to investigate the changes in intestinal tissue structure, digestive enzymes, malondialdehyde content, and antioxidant enzyme activities and their patterns during the early developmental stage of Brachymystax tsinlingensis. This information can be applied to increase the survival rate of fry, protect the species resources, and enrich the species' quantity. This work explores the digestive system characteristics of Brachymystax tsinlingensis during early developmental stages and aims to solve the problem of high lethality of fry during the transgression period, which is crucial for the artificial propagation and population conservation of endangered fishes. This study was carried out on intestinal tissue, digestive enzymes, and antioxidant enzyme activities in the early development stage of Brachymystax tsinlingensis. Ten random samples during endogenous nutrition (7, 10, and 11 days after hatching), mixed nutrition (13 and 19 DAH), and exogenous nutrition (31, 33, 39, 45, and 73 DAH) were collected by histological and biochemical analysis methods. The results showed that the intestine of Brachymystax tsinlingensis already has four layers initially at 7 DAH, and the intestinal gland tissue is evident at 73 DAH. The contents of total protein (TP) and the activities of lipase (LPS) and trypsin (TPS) were maximal at 39 DAH, and the activities were 3.20 ± 0.26 mg/mL, 2.52 ± 0.69 U/g, and 2717.45 ± 295.26 U/mg, respectively. Catalase (CAT) and glutathione peroxidase (GSH-PX) activities both showed the lowest values at 39 DAH, which were 0.57 ± 0.11 U/mg and 3.35 ± 0.94 U/mg, respectively. The activity of amylase (AMS) and the content of malonaldehyde (MDA) increased, and the highest values were reached at 45 DAH (1.32 ± 0.41 U/mg) and 73 DAH (1.29 ± 0.43 nmoL/mg), respectively. Superoxide dismutase (SOD) and GSH-PX activities both showed a peak value at 7 DAH (126.58 ± 20.13 U/mg and 6.47 ± 1.86 U/mg). Overall, the changes in intestinal tissue, digestive enzymes, and antioxidant enzyme activities at 39 DAH of Brachymystax tsinlingensis are inseparable from different vegetative stages during the developmental period, and these results can provide a reference for the proliferation and cultivation of Brachymystax tsinlingensis resources. [ABSTRACT FROM AUTHOR]

Simple Summary: Altering aquatic environments with global warming can have a profound impact on fish species. This study employed transcriptome sequencing to analyze alternative splicing in the gills of largemouth bass after heat stress. We observed an increase in alternative splicing events (674) and differential alternative splicing genes (517). Enrichment analysis revealed significant associations with immune-related gene ontology (GO) terms and KEGG pathways, notably necroptosis, apoptosis, and C-type lectin receptor signaling. These results emphasize that some RNA splicing-related genes are involved in the response of largemouth bass to high temperatures. Temperature is one of the critical factors affecting the physiological functions of fish. With ongoing global warming, changes in water temperature have a profound impact on fish species. Alternative splicing, being a significant mechanism for gene expression regulation, facilitates fish to adapt and thrive in dynamic and varied aquatic environments. Our study used transcriptome sequencing to analyze alternative splicing in largemouth bass gills at 34 °C for 24 h. The findings indicated an increase in both alternative splicing events and alternative splicing genes after high temperature treatment. Specifically, the comparative analysis revealed a total of 674 differential alternative splicing events and 517 differential alternative splicing genes. Enrichment analysis of differential alternative splicing genes revealed significant associations with various gene ontology (GO) terms and KEGG pathways, particularly in immune-related pathways like necroptosis, apoptosis, and the C-type lectin receptor signaling pathway. These results emphasize that some RNA splicing-related genes are involved in the response of largemouth bass to high temperatures. [ABSTRACT FROM AUTHOR]

With the expanding application of lightweight wooden structures in modern construction, the load-bearing capacity of ordinary triangular single-span wooden trusses limits the applicability of lightweight wooden structures. As a result, triangular multi-span wooden trusses have emerged to replace single-span wooden trusses. In practice, multi-span wooden trusses are composed of multiple single-span lightweight wooden trusses, with connections between members using metal plates, a field that has been relatively well researched. However, connections between spans are primarily made with nails in actual engineering, and there has been little research on the use of wooden pins to connect multi-span wooden trusses. To study the mechanical performance of multi-span wooden trusses connected by wooden pins, this paper innovatively combines existing equipment with a self-designed pulley assembly device to conduct a continuous static full-scale loading test on double-span wooden trusses connected by wooden pins of three different diameters. We comprehensively evaluate which type of wooden pin is more suitable for triangular multi-span wooden trusses. The results indicate that the 16 mm diameter wooden pin provides the best energy dissipation performance for connected beam trusses. The 20 mm diameter wooden pin offers the best performance stability. The 20 mm diameter wooden pin also demonstrates a good load-bearing capacity and resistance to deformation. Overall, the 20 mm diameter wooden pin exhibits the best connection performance in triangular beam trusses. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are crystalline organic porous polymers that can be precisely integrated by building blocks to achieve pre‐designed composition, components, and functions, making them a powerful platform for the development of molecular devices in the field of electrocatalysis. The precise control of channel/dopant positions and highly ordered network structures of COFs provide an ideal material system for the applications of advanced electrocatalysis. In this paper, the topological structure design and synthesis methods of COFs are reviewed in detail, and their design principles are deeply analyzed. In addition, the applications of COFs and their derivatives in the field of electrocatalysis are systematically summarized and the optimization strategies are proposed. Finally, the application prospects of COFs and their derivatives in electrocatalysis and the challenges that may be encountered in the future are prospected, providing helpful guidance for future research. [ABSTRACT FROM AUTHOR]