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Summary: In plant species, anthocyanin accumulation is specifically regulated by light signaling. Although the CONSTITUTIVELY PHOTOMORPHOGENIC1/SUPPRESSOR OF PHYA‐105 (COP1/SPA) complex is known to control anthocyanin biosynthesis in response to light, the precise mechanism underlying this process remains largely unknown.Here, we report that Increase in BONSAI Methylation 1 (IBM1), a JmjC domain‐containing histone demethylase, participates in the regulation of light‐induced anthocyanin biosynthesis in Arabidopsis.The expression of IBM1 was induced by high light (HL) stress, and loss‐of‐function mutations in IBM1 led to accelerated anthocyanin accumulation under HL conditions. We further identified that IBM1 is directly associated with SPA1/3/4 chromatin in vivo to establish a hypomethylation status on H3K9 and DNA non‐CG at these loci under HL, thereby releasing their expression. Genetic analysis showed that quadruple mutants of IBM1 and SPA1/3/4 resemble spa134 mutants. Overexpression of SPA1 in ibm1 mutants complements the mutant phenotype.Our results elucidate the significance and mechanism of IBM1 histone demethylase in the epigenetic regulation of anthocyanin biosynthesis in Arabidopsis under HL conditions. [ABSTRACT FROM AUTHOR]

Vortex structures and flow scenarios of noncircular vortex rings impinging onto walls were studied by conducting a large eddy simulation. Three orifice aspect ratios, ARs = 3, 5, and 7, and six dimensionless orifice-to-wall distances, in the range H = 0.71–1.90, were considered for elliptic impinging synthetic jets. At H = 0.95–1.19, the results exhibit different flow scenarios from those of circular vortex rings, which directly interact with the wall to produce a secondary vortex ring. New scenarios are attributed to mutual interactions between the primary vortex ring, the arc-shaped vortex, the wall, and the arc-shaped vortex is unique to noncircular vortex rings. These scenarios are further divided into two categories depending on whether the primary vortex ring can merge with the arc-shaped vortex, which is strongly affected by their separation distance and circulation ratio at the onset of vortex–wall interactions. For small separation distance and circulation ratio, the primary vortex ring swallows the arc-shaped vortex, leading to a strong crescent-shaped secondary vortex or a secondary vortex ring at different ARs. However, as the separation distance or circulation ratio increases, the interactions between the primary vortex ring and arc-shaped vortex weaken so that the latter escapes from entrainment by the primary vortex ring, leading to a weak crescent-shaped vortex. Finally, an AR-H map is constructed to illustrate the flow scenarios for all the cases. These findings provide new insights into the intricate dynamics of noncircular ring–wall interactions and may help us understand the heat transfer performance of noncircular impinging synthetic jets. [ABSTRACT FROM AUTHOR]

HSP20 emerges as a novel regulator of autophagy in the heart. Nonetheless, the detailed function of HSP20 in the liver and its effect on autophagy remain unknown. Here, we observed that HSP20 expression is increased in liver tissues from mice and patients with metabolic dysfunction–associated steatotic liver disease (MASLD), formerly known as nonalcoholic fatty liver disease. Liver-specific downregulation of HSP20 mitigates hepatic steatosis and insulin resistance in obese mice, while upregulating HSP20 promotes lipid deposition and hepatocyte cell death. Mechanistically, liquid chromatography–tandem mass spectrometry revealed that HSP20 interacts with phosphorylated extracellular regulated protein kinase 2 (ERK2) and prevents its dephosphorylation by dual specificity phosphatase 6, leading to ERK2-mediated repression of autophagy and resulting in aggravated saturated fatty acid (SFA)–triggered hepatocyte death. Importantly, such adverse effects could be ameliorated by ERK inhibitor. Our data reveal a framework of how HSP20 increases susceptibility of SFA-induced liver injury through enhancing ERK2 phosphorylation, which represents a plausible therapeutic intervention to combat MASLD. Article Highlights: HSP20 expression was increased in the livers of mice and people living with metabolic dysfunction–associated steatotic liver disease and positively correlated with steatosis grade and body mass. Upregulating HSP20 sensitizes hepatocytes to lipotoxicity by inhibiting autophagy. HSP20 interacts with phosphorylated extracellular regulated protein kinase 2 and prevents its dephosphorylation by phosphatase dual specificity phosphatase 6, leading to aggravation of saturated fatty acid–triggered hepatocyte death by suppressing autophagy function. The HSP20-extracellular regulated protein kinase 2 pathway is an important target to maintain liver homeostasis in patients with metabolic disorders. [ABSTRACT FROM AUTHOR]

Tracheal stenosis is commonly caused by injury, resulting in inflammation and fibrosis. Inhibiting inflammation and promoting epithelization can reduce recurrence after initial successful treatment of tracheal stenosis. Steroids play an important role in tracheal stenosis management. This study in vitro evaluated effectiveness of a polydopaminated polycaprolactone stent coated with dexamethasone‐eluting poly(lactic‐co‐glycolic) acid microparticles (μPLGA) for tracheal stenosis management. Polydopamination was characterized by Raman spectroscopy and promoted epithelialization while dexamethasone delivery reduced macrophage activity, assessed by individual cell area measurements and immunofluorescent staining for inducible nitric oxide synthase (iNOS). Dexamethasone release was quantified by high‐performance liquid chromatography over 30 days. Activation‐related increase in cell area and iNOS production by RAW 264.7 were both reduced significantly (p <.05) through dexamethasone release. Epithelial cell spreading was higher on polydopaminated polycaprolactone (PCL) than PCL‐alone (p <.05). Force required for stent migration was measured by pullout tests of PCL‐μPLGA stents from cadaveric rabbit and porcine tracheas (0.425 ± 0.068 N and 1.082 ± 0.064 N, respectively) were above forces estimated to occur during forced respiration. Biomechanical support provided by stents to prevent airway collapse was assessed by comparing compressive circumferential stiffness, and stiffness of the stent was about 1/10th of the rabbit trachea (0.156 ± 0.023 N/mm vs. 1.420 ± 0.194 N/mm, respectively). A dexamethasone‐loaded PCL‐μPLGA stent platform can deliver dexamethasone and exhibits sufficient mechanical properties to anchor within the trachea and polydopamination of PCL is conducive to epithelial layer formation. Therefore, a polydopaminated PCL‐μPLGA stent is a promising candidate for in vivo evaluation for treatment of tracheal restenosis. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the bright and dark sides of environmental, social and governance (ESG) during the COVID-19 pandemic, including both the outbreak and recovery periods, for the Chinese hospitality industry. Design/methodology/approach: Using panel data of 564 firm-quarter observations from 2018 to 2020, the authors adopt fixed-effects regression estimation with standard errors clustered at the firm level. To address potential endogeneity concerns, the authors also use the two-stage least squares estimator with instrumental variables. Findings: The results suggest that ESG plays different roles in market- and accounting-based performance during the COVID-19 outbreak and recovery periods. Specifically, ESG practices show a bright side as a reputation builder to mitigate the negative pandemic impact on market-based performance, whereas the dark side of ESG practices consumes firm resources to aggravate the negative pandemic impact on accounting-based performance during the coronavirus outbreak. These results also suggest hospitality companies benefit bountifully from ESG practices during the COVID-19 recovery. Practical implications: ESG plays a vital role for hospitality firms by providing insurance-like protection during and after the COVID-19 outbreak. Additionally, hospitality firms should evaluate their capability to adapt resource-consuming ESG practices. Originality/value: Existing hospitality COVID-19 studies have investigated the effect of ESG on firm performance within a short period with mixed results. This study extends the literature by showing the different effects of ESG practices on market- and accounting-based performance during the COVID-19 outbreak and recovery periods. [ABSTRACT FROM AUTHOR]