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Based on multi‐model large‐ensemble experiments provided by Polar Amplification Model Intercomparison Project (PAMIP), we investigate the influence of the projected sea ice loss in Barents‐Kara Seas (BKS) and Sea of Okhotsk (SOK) on the Arctic stratospheric polar vortex (SPV). Results show that future BKS sea ice reduction leads to a weakened SPV during November‐February by enhancing the upward‐propagating planetary wave 1, which is more pronounced during Quasi‐Biennial Oscillation (QBO) easterly than westerly phase. Through weakening the upward‐propagating planetary wave 2, future SOK sea ice reduction is favorable for a strengthened SPV during January‐April. Inter‐model spread in the magnitudes of SPV responses to BKS sea ice reduction can be largely explained by the divergent planetary wave responses, but less so for SOK sea ice reduction. Results from a linearized baroclinic model further validate the importance of the planetary‐scale wave responses in explaining the differing SPV responses to sea‐ice loss over the two regions. Plain Language Summary: Arctic sea ice reduction influences the Northern Hemispheric weather and climate through modulating Arctic stratospheric polar vortex, which is a band of strong westerly encircling the pole during winter at ∼15–40 km above the Earth's surface. However, sea ice reduction over different regions could lead to different effects on the polar vortex. Here, we compare the effects of future sea ice reduction over the Barents‐Kara Seas, in the far‐north Atlantic Ocean, and the Sea of Okhotsk, in the northwest Pacific Ocean. We use carefully designed numerical simulations to estimate the effects of sea ice reduction, separately in the above‐mentioned two regions, on the polar vortex. Sea ice reduction over the Barents‐Kara Seas weakens the polar vortex, whereas sea ice reduction over Sea of Okhotsk strengthens the polar vortex. These contrasting effects are explained by opposing changes in wave activity entering the stratosphere from below. Barents‐Kara sea ice reduction leads to the strengthened upward propagating planetary waves, which break in the stratosphere and slow the polar vortex. Conversely, Okhotsk sea ice loss reduces upward waves and strengthens the polar vortex. Key Points: Barents‐Kara and Sea of Okhotsk sea ice loss weakens and strengthens polar vortex, respectively, with attendant changes in SSW frequencyPlanetary wave responses to Barents‐Kara and Okhotsk sea ice loss interfere constructively and destructively with mean flow, respectivelyPolar vortex weakening induced by Barents‐Kara sea ice loss is greater during easterly than westerly Quasi‐Biennial Oscillation phase [ABSTRACT FROM AUTHOR]

Background: The inflammatory response is a key factor in the pathogenesis of cerebral ischemia/reperfusion injury (CIRI), and anti-inflammatory interventions may offer a promising therapeutic strategy. Forsythoside B (FB) is a phenylethanoid glycoside isolated from Forsythiae fructus, which has been reported to have anti-inflammatory effects. However, the mechanism of the neuroprotective effect of FB on CIRI remains unclear. Methods: Adult male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion/reperfusion (MCAO/R). FB was administered intraperitoneally for 3 days prior to MCAO/R. Cerebral infarct volume and neurological deficit score were used as indices to evaluate MCAO/R injury. The serum levels of inflammatory factors and antioxidant enzymes were measured. The activation of silent information regulator 2 homolog 1 (Sirt1) and the inhibition of the nucleotide-binding oligomerization domain-like receptor with a pyrin domain 3 (NLRP3) pathway were assessed through western blot and immunohistochemistry analysis. Furthermore, the rats were treated with Sirt1 shRNA 3 days before MCAO/R by stereotactical injection into the ipsilateral hemispheric region to assess the impact of Sirt1 knockdown on the protection of FB during MCAO/R. Results: FB reduced cerebral infarct volume and neurological deficit score in MCAO/R rats. FB reduced pathological changes and cell apoptosis in the hippocampal CA1 region and cortex on the ischemic side of rats. FB inhibited the serum levels of inflammatory factors and increased the activities of antioxidant enzymes. Further study showed that FB inhibited the activation of the NLRP3 pathway and induced Sirt1 activation. Conclusion: FB demonstrated neuroprotective and anti-inflammatory effects by inhibiting the NLRP3 pathway through Sirt1 activation in CIRI. [ABSTRACT FROM AUTHOR]

Background: Urinary incontinence (UI) might be linked to suicidal ideation, but we do not yet have all the relevant details. This study aimed to dig deeper into the connection between UI and suicidal ideation using data from the National Health and Nutrition Examination Survey (NHANES). Methods: We examined 31,891 participants aged ≥ 20 years from NHANES 2005–2018 who provided complete information. We used standardized surveys to check for UI and signs of suicidal ideation. To better understand this relationship, we used statistical tools such as multivariable logistic regression, subgroup analysis, and sensitivity analyses. Results: Among the 31,891 participants, 28.9% reported UI and 10.7% reported suicidal ideation. Those with UI exhibited a significantly greater incidence of suicidal ideation (15.5%) than did those without UI (8.8%, P < 0.001). After adjusting for various factors, including age, sex, marital status, socioeconomic status, educational level, lifestyle factors, and chronic comorbidities, UI remained significantly associated with suicidal ideation (OR:1.54, 95% CI = 1.39–1.7, P < 0.001). Among all types of UI, MUI participants were more likely to experience suicidal ideation. Compared with no UI, higher odds of suicidal ideation suffered from MUI (OR:2.11, 95%CI:1.83–2.44, P < 0.001), SUI (OR:1.4, 95%CI:1.19–1.65, P < 0.001), UUI(OR:1.37,95%CI:1.16–1.62, P < 0.001) after full adjustment. With the exception of individuals living with a partner, the remaining subgroups exhibited a positive correlation between urinary incontinence and suicidal ideation, considering that factors such as age, sex, and prevalent comorbidities such as hypertension, depression, and diabetes did not reveal any statistically significant interactions (all P > 0.05). Sensitivity analyses, incorporating imputed missing covariates, did not substantially alter the results (OR: 1.53, 95% CI: 1.4–1.68, P < 0.001). Conclusion: Urinary incontinence may correlate with increased suicidal ideation risk, priority screening for suicidal ideation and timely intervention are essential for individuals with urinary incontinence, but prospective studies are needed to verify the results. [ABSTRACT FROM AUTHOR]

Snowpacks are natural water reservoirs providing a considerable amount of water for humans and ecosystems. However, current global snow products (e.g., ESA GlobSnow v3.0), lack high spatial resolution and regional calibrations necessary to capture the high heterogeneity of snow water equivalents (SWEs) in complex Asian mountainous terrains. Therefore, our understanding of snow drought characteristics in China remains limited. Herein, we used an improved SWE product calibrated specifically for China to explore the characteristics of snow droughts, delineated by a standardized SWE index (SWEI) between 1993 and 2019. Our analysis was focused over three main snow‐covered regions of China: Qinghai–Tibet Plateau (QTP), northern Xinjiang, Northeast China. Especially during the period from 1993 to 2010, we found that the SWEI increased significantly at rates of 0.022/yr (Northeast China), 0.017/yr (northern Xinjiang), and 0.011/yr (QTP) (p < 0.01, Mann‐Kendall trend test). Increased SWEI contributed to decreasing snow drought events across China, with an obvious short‐term characteristic, whilst area proportion of the identified 1‐month snow droughts was above 46.5% across three regions. Furthermore, we found that the occurrence of snow droughts was likely mediated by large‐scale atmospheric circulation, since increased water vapor transport caused a significant vapor flux convergence in cold seasons over three regions, especially in northern Xinjiang and Northeast China. Plain Language Summary: Snow droughts are caused by snow water equivalent (SWE) deficits and pose a significant climatic risk to humans and natural systems, particularly in snow‐dependent watersheds. Hence, understanding their main characteristics and driving forces is crucial for diagnosing and predicting potential climate risks. However, current research is not clear in terms of the occurrence and characteristics of snow drought in China. Therefore, we aim to investigate snow droughts based on specially calibrated SWE data in China. Alongside the increase of SWE in the three main snow‐covered areas across China, we found that the intensity of snow drought in China showed a clear downward trend, whilst both the extent and number of snow droughts decreased rapidly. Overall, these changes were likely regulated by atmospheric circulation, with the southward water vapor flux clearly increasing, providing a reliable source of water vapor and promoting the increase of snowfall. Our findings provide an important basis for the management and regulation of spring water resources to snow droughts in snow‐dependent watersheds. Key Points: A reliable snow water equivalent product calibrated specifically for China was used to assess snow droughtsBetween 1993 and 2019, the occurrence of snow droughts decreased rapidly, alongside their intensity and extentThe occurrence of snow droughts was regulated by large‐scale water vapor transport [ABSTRACT FROM AUTHOR]

ε-Poly-L-lysine (ε-PL) is a natural and safe food preservative mainly produced by the aerobic, filamentous bacterium Streptomyces albulus. Therefore, it is crucial to breed superior ε-PL-producing strains to enhance fermentation efficiency to reduce production costs. Metabolic engineering is an effective measure for strain modification, but there are few reports on key genes for ε-PL biosynthesis. In this study, metabolic flux analysis was employed to identify potential key genes in ε-PL biosynthesis in S. albulus WG-608. A total of six potential key genes were identified. Three effective key genes (ppc, pyc and pls) were identified for the first time in ε-PL biosynthesis through overexpression experiments. It also presents the first demonstration of the promoting effects of ppc and pyc on ε-PL biosynthesis. Three genes were then co-expressed in S. albulus WG-608 to obtain OE-ppc-pyc-pls, which exhibited an 11.4% increase in ε-PL production compared to S. albulus WG-608, with a 25.5% increase in specific ε-PL production. Finally, the metabolic flux analysis of OE-ppc-pyc-pls compared to S. albulus WG-608 demonstrated that OE-ppc-pyc-pls successfully altered the metabolic flux as expected. This study not only provides a theoretical basis for the metabolic engineering of ε-PL-producing strains but also provides an effective approach for the metabolic engineering of other metabolites. [ABSTRACT FROM AUTHOR]