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Bifunctional thiourea-catalyzed asymmetric [3 + 2] annulation reactions of 2-isothiocyanato-1-indanones with barbiturate-based olefins have been developed to afford chiral dispiro[indene-pyrrolidine-pyrimidine]s. Through this strategy, the target products could be obtained in good to excellent yields with excellent stereoselectivities. In addition, the synthetic utility was verified through a gram-scale synthesis, one-pot three-component reactions and further transformation experiments of the products.

Eleven undescribed guaiane-type sesquiterpenoids, named daphnegenols A-K (1–11) and a known analog (12) were targeted for isolation from the root of Daphne genkwa by LC-MS/MS-based molecular networking. Their diverse structures were elucidated through extensive spectroscopic methods, quantum chemical calculation and X-ray single crystal diffraction, including 5/7 bicycle, 5/6/7 tricycles and 5/6/5 tricycles guaiane-type sesquiterpenoid. Daphnegenol A (1) possessed a rare six membered oxyheterocyclic ring which was constructed by oxidation and cyclization at C-1 and C-11. The anti-acetylcholinesterase and anti-neuroinflammatory activities of compounds 1–12 were measured.

BackgroundCell electroporation technology under pulsed electric field has been widely used in water treatment, food sterilization, tissue ablation and other applications. Different electroporation applications have different requirements for the pulse waveform.PurposeThis study aims to propose a new pulse generator structure consisting of a special full bridge (FB) module and multiple half bridge (HB) modules to generate bipolar pulse voltages, stepped waves and combination of narrow and wide pulses can also be realized by only changing the switching sequence.MethodsFirst of all, the structure and working principle of novel circuit were elaborated. Then, a main circuit structure composed of 1 full-bridge module and 4 half-bridge modules composed of 12 switches were designed and implemented. Bipolar pulse voltages, stepped waves and combination of narrow and wide pulses were realized by only changing the switching sequence. Finally, verification of the power supply for cell electroporation experiments was carried out in the potato tuber treatment experiment. [ResultsandConclusions] When each level of capacitor is charged at 220 V, bipolar pulse voltage output with ±2 kV and adjustable pulse width of 1~10 μs is realized. Furthermore, the output of a unipolar 9-level step voltage and a combination of wide and narrow pulses are achieved by controlling the switching sequence. Experiment of potato tuber treatment verified the feasibility of this pulse generator.

Abstract Arecoline, a major alkaloid within areca nut extract, is recognized as the primary active carcinogen promoting oral squamous cell carcinoma (OSCC) pathological development. Dysregulation of N6‐methyladenosine (m6A) methyltransferase components (e.g., Fat mass and obesity‐associated protein [FTO] and methyltransferase‐like 3 [METTL3]) are closely associated with multiple cancer progression, including oral cancer. However, the biological function role of FTO in arecoline‐induced oral cancer is largely unknown. We identified that FTO was significantly upregulated in OSCC tissues from patients with areca nut chewing habits and chronic arecoline‐treated OSCC cell lines. Depletion of FTO attenuated the arecoline‐promoted stemness, chemoresistance, and oncogenicity of OSCC cells. Finally, we revealed that FTO was negatively regulated by a transcription factor forkhead box protein A2 (FOXA2) in OSCC cells. This study, for the first time, demonstrated that FTO plays an oncogenic role in arecoline‐induced OSCC progression. Thus, developing new therapeutic agents targeting FTO may serve as a promising method to treatment OSCC patients, especially those with areca nut chewing habits.

Abstract Diabetes is a chronic metabolic disease characterized by high glucose concentration in blood. Conventional management of diabetes requires skin pricking and subcutaneous injection, causing physical pain and physiological issues to diabetic individuals. Hydrogels possess unique advantages such as lightweight, stretchability, biocompatibility, and biodegradability, offering the opportunities to be integrated as flexible devices for diabetes management. This review highlights the development of hydrogels as flexible materials for diabetes applications in glucose monitoring, insulin delivery, wound care, and cell transplantation in recent years. Challenges and prospects in the development of hydrogel-based flexible devices for personalized management of diabetes are discussed as well.

To measure the degree of information granulation, granularity has attracted many researchers extensive attention in the field of granular computing. One of the important and widely accepted patterns is parameterized granularity. Based on such parameterized granularity, when solving the problem of attribute reduction, it is often necessary to calculate the reducts related to each parameter until all of the reducts have been obtained. Obviously, this method will result in high time consumption. To fill such a gap, a multi-granularity attribute reduction approach based on continuous parameters is proposed. Firstly, a new constraint related to attribute reduction is constructed by using the interval of continuous parameters and the monotonicity of uncertainty measure in rough set. Secondly, a forward greedy searching algorithm is designed to derive the continuous parameters based reducts. Finally, 8 UCI data sets are selected for experimental comparisons and analyses. The results show that compared with single granularity based reducts in terms of multiple parameters, attribute reduction related to continuous parameters can greatly reduce the elapsed time of obtaining reduct without causing significant changes in the classification performance. This study provides a new solution for multi-granularity based modeling and feature selection from a continuous perspective.

The operating stability of guide roller in the printing machine is an important factor to affect the paper tape transmission, and the severe vibration of guide roller can becomes erratic the printing quality. In this paper, a novel distributed annular diffuse vibration isolator is proposed to suppress the shaft vibration of the guide roller and improve the printing performance. For discussing isolation performance, dynamic stiffness method is used for establishing the theoretical model of the proposed isolator, and calculate the vibration transmission ratio and normalized modal displacement. The results indicate that three vibration isolation frequency bands, which are 86–140, 182–224, and 236–2000 Hz, can effectively block vibration energy transmission; the normalized modal displacement decreases less between 0 and 50 Hz, decreases significantly between 50 and 1000 Hz. Finally, the experimental platform on vibration isolator of guide roller is set up to verify the vib-isolating performance. These experiment results confirm the vibration transmission ratios obtained from the experiments consistently align with the trends predicted by the theoretical model, and show that vibration acceleration RMS reaches the maximum when the driving frequency is 50 Hz, the maximal RMS before isolator is 122.7 dB; When the driving frequency is 20 Hz, the RMS reaches the minimum, and the minimum is 94 dB. Thus it indicted that the proposed vibration-isolator has excellent vibration isolation performance, can isolate the vibration of the guide roller effectively in a wide frequency range. [ABSTRACT FROM AUTHOR]

Arc sag is an important parameter in the design and operation and maintenance of transmission lines and is directly related to the safety and reliability of grid operation. The current arc sag measurement method is inefficient and costly, which makes it difficult to meet the engineering demand for fast inspection of transmission lines. In view of this, this paper proposes an automatic spacer bar segmentation algorithm, CM-Mask-RCNN, that combines the CAB attention mechanism and MHSA self-attention mechanism, which automatically extracts the spacer bars and calculates the center coordinates, and combines classical algorithms such as beam method leveling, spatial front rendezvous, and spatial curve fitting, based on UAV inspection video data, to realize arc sag measurement with a low cost and high efficiency. It is experimentally verified that the CM-Mask-RCNN algorithm proposed in this paper achieves an AP index of 73.40% on the self-built dataset, which is better than the Yolact++, U-net, and Mask-RCNN algorithms. In addition, it is also verified that the adopted approach of fusing CAB and MHSA attention mechanisms can effectively improve the segmentation performance of the model, and this combination improves the model performance more significantly compared with other attention mechanisms, with an AP improvement of 2.24%. The algorithm in this paper was used to perform arc sag measurement experiments on 10 different transmission lines, and the measurement errors are all within ±2.5%, with an average error of −0.11, which verifies the effectiveness of the arc sag measurement method proposed in this paper for transmission lines.

In order to study the influence of electromagnetic (EM) effect and load change on the modal characteristics and dynamic response of gear transmission system driven by permanent magnet synchronous motor (PMSM), a electromechanical coupling dynamic model is established. The composite air gap permeability coefficient is introduced, and the formula of permanent magnet flux linkage under the influence of space harmonic and cogging effect is derived. The variation laws of gear meshing stiffness and bearing support stiffness under the influence of load change are simulated and analyzed. The natural frequency and vibration modal under different load, flux linkage and PI controller gain are revealed. On this basis, the influence of EM effect and load change on the resonance domain is analyzed through frequency sweep analysis and time domain simulation. Results indicate that the 1st order natural frequency and resonance amplitude will increase with the load, and the influence of PMSM EM excitation will gradually dominate. The increase of the flux linkage and speed loop controller gain Kpω will reduce the 1st order natural frequency. When Kpω=123, a new mode appears, and there is a modal transition between the new mode and mode 1 when Kpω=161. The research results can provide theoretical guidance for improving the transmission performance and structure optimization design of the permanent magnet gear transmission system. [ABSTRACT FROM AUTHOR]

Simple Summary: Metapenaeus ensis, valued in Chinese aquaculture for its salinity and temperature tolerance, has seen limited research on germplasm evaluation. This study compared M. ensis from Sanya, Zhuhai, and Raoping, China. A nutritional analysis showed no significant differences in ash, moisture, and protein across populations but did reveal variations in fat and sugar content, with Sanya and Raoping having higher fat and Zhuhai having higher sugar. Amino acid composition favored Sanya's population, while a fatty acid analysis highlighted Raoping's advantages. Physiological and biochemical characteristics were similar among populations, but genetic diversity was low, with notable differences between Sanya and Zhuhai populations. The study provides insights into regional germplasm advantages and genetic characteristics for future M. ensis research and breeding. Due to its high tolerance to salinity and temperature, as well as its strong adaptability, Metapenaeus ensis holds an important position in the Chinese aquaculture industry. However, studies on the evaluation of its germplasm resources remain insufficient. This research conducted an in-depth comparative evaluation of M. ensis from three representative farming regions in China: Sanya, Zhuhai, and Raoping. The nutritional analysis of muscle tissue showed no statistically significant differences in crude ash, moisture, and crude protein content among the populations (p > 0.05). However, significant differences were observed in crude fat and total sugar content (p < 0.05). The MeSY and MeRP populations had higher crude fat content than the MeZH population (p < 0.05), while the MeZH population exhibited the highest total sugar content. In terms of amino acid composition, the MeSY population had relatively higher total essential amino acid content and proportion, as well as higher total amino acid content, both of which were statistically significant (p < 0.05). A fatty acid composition analysis further highlighted the advantages of the MeRP population in several key fatty acids (p < 0.05). Physiological and biochemical analyses showed no significant differences among the three populations in total antioxidant capacity, superoxide dismutase activity, or catalase activity (p > 0.05). A genetic diversity analysis indicated that M. ensis has relatively low diversity, with the MeSY population showing higher SNP density and nucleotide diversity. A genetic differentiation analysis revealed significant genetic differentiation between the MeSY and MeZH populations, while differentiation between the MeZH and MeRP populations was relatively smaller. This comprehensive assessment of nutritional components, amino acids, fatty acids, antioxidant capacity, and genetic diversity highlights the advantages of germplasm resources from different regions. These findings provide valuable insights for future research on the genetic characteristics and breeding potential of M. ensis. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigates the nutritional quality and genetic diversity of Pacific white shrimp (Litopenaeus vannamei) from three different aquaculture farms in Guangdong Province, China. We assessed the shrimp's muscle tissue for key nutrients like protein, fat, and amino acids, alongside a detailed genetic analysis. Our findings reveal that the nutritional content is consistent across all three populations, indicating the reliable protein quality and essential nutrient levels critical for shrimp health and growth. However, significant differences in genetic diversity were observed, with one population exhibiting reduced genetic diversity and signs of inbreeding. These results underscore the necessity of implementing effective breeding strategies to enhance genetic diversity and ensure the sustainable development of L. vannamei in aquaculture. This study provides essential insights for optimizing breeding practices to maintain the long-term health and productivity of this vital species in the aquaculture industry. This study aimed to evaluate the quality and genetic diversity of farmed Litopenaeus vannamei across three distinct populations from Maoming City (MM), Zhanjiang City (ZJ), and Yangjiang City (YJ) in Guangdong Province. Muscle tissues from L. vannamei were analyzed for phenotypic traits, conventional nutrients, amino acids, and fatty acids, while genetic diversity was assessed using whole genome sequencing techniques. The analysis revealed that the crude protein content in shrimp across the three populations ranged from 20.87 to 21.95 g/100 g, crude fat content ranged from 0.90 to 1.50 g/100 g, essential amino acid content ranged from 5.55 to 5.86 g/100 g, total amino acid content ranged from 14.73 to 15.27 g/100 g, total fatty acid content ranged from 682.73 to 793.97 mg/100 g, total antioxidant capacity (T-AOC) ranged from 2.68 to 2.72 μmol/g, superoxide dismutase (SOD) activity ranged from 1021.97 to 1057.21 U/g, and catalase (CAT) activity ranged from 78.65 to 81.33 μmoL/min. No significant differences were observed in ash and crude fat levels among conventional nutrients, nor in the biochemical indexes T-AOC, CAT, and SOD. Genetic analysis showed that the single nucleotide polymorphism density (SNP/Kb) ranged from 15.323 to 17.461, nucleotide diversity (π) ranged from 2.98 × 10−5 to 15.84 × 10−5, polymorphism information content (PIC) ranged from 0.300 to 0.317, heterozygosity (Ho) ranged from 0.033 to 0.048, and inbreeding coefficients (FIS) ranged from 0.834 to 0.887. The genetic differentiation index (FST) values among the three populations ranged from 0.056 to 0.106. This study provides an evaluation of the germplasm resources and genetic diversity of farmed L. vannamei, offering insights for the efficient management and sustainable utilization of this species' germplasm resources. [ABSTRACT FROM AUTHOR]

Penaeus monodon is one of the world's most important aquaculture species, with its host-associated microbial community playing a crucial role in its growth, metabolism, immune response, and adaptation. In our study, we utilized Illumina high-throughput sequencing to investigate the composition, structure, and function of the intestinal microbial communities of P. monodon from two different regions in Guangdong. Our results identified 176 phyla across both populations, with Proteobacteria and Firmicutes being predominant. Furthermore, we identified 3095 genera, with Photobacterium, Vibrio, and Aliiroseovarius being the most dominant. Functional gene analysis based on KEGG data indicated that the carbohydrate metabolism and amino acid metabolism were significant at the secondary metabolic pathway level. The eggNOG functional annotation revealed that the genes involved in replication, recombination, and repair are of paramount importance. The CAZy annotation results indicated that Glycoside Hydrolases (GH) have the highest abundance. The Pfam annotation analysis showed that the two most prevalent domains are P-loop NTPase and NADP Rossmann. Our investigation provides a reference for species-level and functional-level analyses of the intestinal microbiota of P. monodon, contributing valuable insights into its microbial ecology. [ABSTRACT FROM AUTHOR]

Salinity is a crucial environmental factor influencing the survival, growth, development, and reproduction of aquatic animals. However, the underlying molecular mechanisms of the shrimp's response to salinity stress are not yet fully understood. Therefore, we used the Illumina NovaSeq 6000 platform to perform transcriptome sequencing of the hepatopancreas of Litopenaeus vannamei under high-salinity (30 PSU), medium-salinity (10 PSU), and low-salinity (0.5 PSU) conditions. We obtained 63.23 Gb of high-quality data and identified 3589 differentially expressed genes (DEGs), including 1638 upregulated and 1951 downregulated genes. Notably, a comparison between the control group (30 PSU) and the low-salinity group (0.5 PSU) revealed that the BBOX1 and CHE1 genes were significantly upregulated, while the ACOX1, MPV, CYP2L1, GCH, MVK, TREt1, and XDH genes were significantly downregulated. These genes are primarily involved in key metabolic pathways, such as fatty acid oxidation, cholesterol metabolism, and hormone synthesis and metabolism. The key genes involved in fatty acid β-oxidation, such as ACOX1, ACAD, HADH, HSD17B4, PECR, CROT, PIPOX, and CG5009, all showed a downward trend, suggesting that L. vannamei may respond to salt stress by regulating fatty acid oxidative metabolism, optimizing energy utilization, and maintaining cell homeostasis under low-salinity conditions. Functional annotation of gene ontology (GO) and KEGG pathway enrichment analysis highlighted the roles of these significant DEGs in the adaptation of L. vannamei to environments of varying salinity, underscoring the importance of metabolic pathways in their adaptive physiological responses. This study provides a crucial molecular biological basis for understanding the molecular mechanisms and physiological protection strategies of L. vannamei under salinity stress. [ABSTRACT FROM AUTHOR]