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Phonon lasers have long been a subject of interest and possess broad application prospects. Much effort is devoted to lay the foundation of realizing phonon lasers using cavity magnomechanical systems, but up to now no related work is carried out to explore the quantum‐squeezing‐engineered phonon laser action in cavity magnomechanics. Here, the phonon laser action is investigated in a three‐mode cavity magnomechanical system built based on a microwave resonator‐yttrium iron garnet sphere composite device, focusing on the effect induced by the magnon‐mode squeezing. It is found that the magnon squeezing can improve the effective magnon–photon and magnon–phonon coupling rates. It is demonstrated that the phonon laser action can be engineered and enhanced by changing the squeezing strength. This scheme provides a new mechanism to improve the effective magnon–photon and magnon–phonon couplings for various applications, and demonstrates the feasibility of realizing high‐gain and low‐threshold phonon lasers with cavity magnomechanical platforms. [ABSTRACT FROM AUTHOR]

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BACKGROUND Taxifolin is a natural dihydroflavonol found in many plants and health products. In the present study, its anti‐obesity and gut microbiota modulating effects were studied. C57BL/6J mice were fed with a high‐fat diet (HFD) supplemented with taxifolin (0, 0.5 and 1 mg mL−1, respectively) in drinking water for 15 weeks. RESULTS: Taxifolin supplementation showed no influence on food and water intake. However, it decreased body weight gain, inhibited fat accumulation, and decreased total cholesterol and triacylglycerol level in mice liver. Taxifolin enhanced superoxide dismutase (SOD) activity in mice liver, which in turn protected the liver from lipid peroxidation damage. It also improved insulin resistance in obese mice. Metagenomic analysis of bacterial 16S rRNA demonstrated that HFD decreased gut microbiota diversity and caused dysbiosis. However, taxifolin improved the gut microbiota diversity and decreased the Firmicutes/Bacteroidetes ratio. In particular, it inhibited Proteobacteria from blooming, this being a signature of dysbiosis in gut microbiota. CONCLUSION: Taxifolin ameliorated the symptoms of obesity, hepatic steatosis, lipid peroxidation, insulin resistance, and gut microbiota dysbiosis in HFD fed C57BL/6J mice. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Cashmere traits were deployed for fiber yield and quality during the domestication of goats. However, the genetic alterations underlying cashmere trait selection are still unclear. We sequenced 120 Chinese native goats, including 2 cashmere goat breeds and 6 ordinary goat breeds. The genome-wide selective sweep of cashmere goat and ordinary goat revealed a novel set of candidate genes as well as pathways, such as nuclear factor–κB and Wnt signaling pathways. Of them, LHX2 , regulating hair follicle development, was evident from the strongest selection signal when comparing the Uhumqin cashmere goat and ordinary goat. Interestingly, we identified a 582-bp deletion at 367 kb upstream of LHX2 with higher frequency in cashmere goats and their ancient relatives. This mutation probably arose along with breeding procedures and is putatively responsible for cashmere production and diameter, as revealed by association studies. Luciferase assay showed that the 582-bp sequence, which acts as an insulator, restrains the expression of LHX2 by interfering with its upstream enhancers. Our findings provide new insights into the genetic formation of cashmere and facilitate subsequent molecular breeding for cashmere goat improvement. [ABSTRACT FROM AUTHOR]

Astilbin is a dihydroflavanol found in many plants and processed foods. Astilbin possesses multiple health-beneficial bioactivities and has received great attention. Hence, the natural source, physicochemical properties, biological activities and metabolism of astilbin are summarized in the present article. Engelhardia roxburghiana Wall. and Smilax glabra Roxb. are the main resource for astilbin purification because of high content. Because of chemical instability, astilbin amount in foods is dependent on the processing and storage conditions. The degradation of astilbin includes isomerization and decomposition. The interconversion of astilbin and its isomers occurs through a chalcone intermediates, which significantly affects the taste of wine during storage. Many factors such as temperature, pH, metal ions and food additives could affect the chemical stability of astilbin. Astilbin exhibits very novel selective immunosuppressive activity, which is not found in other compounds. The rhamnose moiety of astilbin is essential for this bioactivity. After digestion, astilbin was mainly absorbed and transported in circulatory blood in its intact form, and only one metabolite, 3'-O-methylastilbin, was found. Although having many bioactivities, astilbin faces the challenge of poor bioavailability. Some promising strategies were developed for improving its bioavailability, particularly through fabrication the zein nanoparticles.

Lipase is a very important digestive enzyme for triglyceride absorption in vivo. The inhibitory activities of 26 dietary flavonoids, including flavone, flavanone, isoflavone and flavanol, on lipase were determined. Flavone exhibited stronger inhibitory activity than other types of flavonoids. Among them, luteolin exhibited the strongest inhibitory activity with IC50 value of 99 ± 11 μM, followed by quercetin and baicalein. The binding affinity of these flavonoids with lipase was investigated by fluorescence titration method. The binding affinity of flavones was stronger than flavanones, and was linearly positively correlated with their inhibitory activity. The binding of flavones on lipase caused the blue-shift of fluorescence, while flavanones caused red-shift. The analysis of structure-activity relationship of flavonoids on lipase revealed that the structure of C ring is very crucial. The hydrogenation of C2=C3 bond and the absence of C=O group in C ring both caused significant decrease of inhibitory activity. Besides, the hydroxylation on ring A and B of flavones increased the activity, while glycosylation weakened the activity. Molecular docking analysis confirmed that C2=C3 bond in C ring of flavones increases the π-conjugation and contributes to maintaining the planarity of flavonoid structure, which favour its Pi-Pi interaction with lipase., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)