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Stomata are channels through which plants exchange H2O and CO2 with the external environment. The regulation of stomatal movement has significant impacts on plant growth, development and stress adaptation. Here, we present a maize R2R3 -MYB transcription factor, ZmMYB56, which regulates high CO2-induced stomatal closure in maize seedlings. ZmMYB56 is highly expressed in stomatal guard cells and is negatively regulated by CO2 and HCO3 -. Loss of ZmMYB56 function leads to insensitivity to high CO2. As a transcription factor, ZmMYB56 binds to a cis-acting element in the ZmHLT1 promoter and regulates its expression. ZmHLT1 plays a key role in CO2- induced maize stomatal movement, and its absence causes a severe weakening of maize's response to ambient CO2. ZmHLT1 expression is negatively regulated by bicarbonate, which does not occur in Zmmyb56 mutants, highlighting the significance of this regulatory relationship in plant responses to CO2 and HCO3 -. Taken together, these results show that ZmMYB56-regulated ZmHLT1 expression is important for high CO2-induced stomatal closure in maize. Our findings provide insight into genetic pathways that could be manipulated to improve maize growth and stress tolerance, especially under increasing atmospheric CO2 concentrations.

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A family of molecular chaperone complexes called chaperonin-containing T-complex protein 1 (TCP-1) subunit genes (CCTs) aids in the folding of numerous proteins. With regard to lung adenocarcinoma (LUAD), this study provided a thorough understanding of the diagnostic and prognostic use of CCTs. The expression of CCTs in LUAD was evaluated by using databases including UALCAN and the Gene Expression Omnibus. Immunohistochemistry (IHC) was conducted to validate the expression of CCTs in LUAD. The mutation in the CCTs was identified through the cBioPortal database, while promoter methylation was measured by the UALCAN database. The prognostic value of CCTs was evaluated using the PrognoScan analysis. The GEPIA2.0 database was used to measure the prognostic value of CCTs and associated Hub genes. Correlation analysis between CCTs expression in LUAD was based on the GEPIA2.0 database. The ROC curves, clinical correlation analysis, gene ontology, Kyoto Encyclopedia of Genes and Genome analysis, and immune cell infiltration analysis were downloaded from The Cancer Genome Atlas database and then analyzed and visualized using the R language. The STRING database was used for protein-protein interaction analysis. Upregulation of CCTs expression in patients with LUAD indicated advanced diseases and a poor prognosis. ROC curve analysis revealed that the CCTs may serve as diagnostic indicators. The functional enrichment analysis showed that CCTs were involved in the mitosis-mediated cell cycle process. Additionally, 10 hub genes associated with CCTs that were linked to LUAD prognosis and tumor progression were identified. Immune cell infiltration analysis showed that CCTs expression in tumor tissues tends to be related to T helper type 2 cell infiltration. This study revealed that CCTs may serve as valuable biomarkers for the diagnosis and targeted therapy of LUAD.

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The gut microbiota is crucial for maintaining the host's intestinal homeostasis and metabolism. This study investigated the effects of fecal microbiota transplantation (FMT) from Ningxiang pigs on the growth performance, fecal microbiota, and serum metabolites of the same-old DLY pigs. The results indicated that the average daily gain of FMT pigs was significantly greater than that of the control (CON) group. Compared to the CON group, the FMT group significantly improved the apparent digestibility of crude fiber, crude ash, gross energy, and calcium of the pigs. The analysis of serum antioxidant status revealed that the activities of total superoxide dismutase and catalase in the serum of pigs in the FMT group were significantly elevated, whereas the level of malondialdehyde was significantly reduced. Furthermore, 16S rRNA sequencing analysis revealed that the Ningxiang pig-derived microbiota altered the fecal microbiota structure and modulated the diversity of the gut microbiota in the DLY pigs. Untargeted LC-MS metabolomics demonstrated that pigs in the FMT group exhibited distinct metabolomic profiles compared to those in the CON group. Significant changes were observed in key metabolites involved in amino acid, lipid, and carbohydrate metabolism. Additionally, a correlation analysis between serum differential metabolites and the gut microbiota revealed that the relative abundance of Lachnospiraceae_NK4A136_group and Corynebacterium was highly correlated with lipid compounds. In conclusion, Ningxiang pig-derived microbiota can alleviate oxidative stress and enhance growth performance in DLY pigs by modulating their gut microbiota and metabolic features.

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OBJECTIVE: This study examines the impact of parental migration on the psychological well-being and development of left-behind children (LBCs) in Zhejiang, China, within the broader context of the country's rural transformations and urban migration. It investigates how intellectual and relational engagement (RE), autonomy (AUT), competence (COM), and relatedness (RES) contribute to resilience (REL) and post-traumatic growth (PTG) in these children, reflecting on the shift from viewing parental separation merely as a source of trauma to recognizing its potential to foster significant personal growth. METHODS: Utilizing a cross-sectional design, the research was conducted in April and May 2023 with 1348 LBCs from a total sample of 4049 students inZhejiang. A two-step random, stratified, cluster-based sampling strategy was employed, and structural equation modeling was used to examine the hypothesized relationships among the constructs. RESULTS: The statistical analysis demonstrated significant positive effects of intellectual engagement (IE), AUT, COM, and RE on both REL and PTG (p < .05 for all). IE strongly correlated with AUT (r = .68, p < .001) and COM (r = .71, p < .001), enhancing REL and facilitating PTG. Additionally, the presence of secure and consistent relationships was identified as crucial for maintaining psychological well-being, with high correlation coefficients (r > .60) underscoring their importance. Notably, REL was found to moderate the relationships among RES, COM, and PTG, highlighting its critical role in the psychological adaptation of left-behind children. CONCLUSION: The study underscores the importance of nurturing intellectual and REs, AUT, and COM to enhance psychological REL and well-being among LBAs. These elements are crucial for supporting the mental health and developmental needs of children facing the challenges of parental migration. The findings advocate for targeted interventions that can address the unique needs of this vulnerable population, emphasizing the potential for growth and adaptation despite adversities.

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Biological nitrogen fixation is the main source of nitrogen in ecosystems. The diversity of soil rhizobia and their effects on soybeans need further research. In this study, we collected soybean rhizosphere samples from eight sites in the black soil soybean planting area in Northeast China. A total of 94 strains of bacteria were isolated and identified using the 16S rRNA and symbiotic genes (nodC, nifH) analysis, of which 70 strains were identified as rhizobia belonging to the genus Bradyrhizobium. To further validate the application effects of rhizobia, we selec-ted seven representative indigenous rhizobia based on the results of phylogenetic analysis, and conducted laboratory experiments to determine their nodulation and the impacts on soybeans. The results showed that, compared to the control without rhizobial inoculation, all the seven indigenous rhizobia exhibited good promoting and nodulation abilities. Among them, strains H7-L22 and H34-L6 performed the best, with the former significantly increasing plant height by 25.7% and the latter increasing root nodule dry weight by 20.9% to 67.1% compared to other indi-genous rhizobia treatments. We tested these two efficient rhizobia strains as soybean rhizobial inoculants in field experiments. The promoting effect of mixed rhizobial inoculants was significantly better than single ones. Compared to the control without inoculation, soybean yield increased by 8.4% with the strain H7-L22 treatment and by 17.9% with the mixed inoculant treatment. Additionally, there was a significant increase in the number of four-seed pods in soybeans. In conclusion, the application of rhizobial inoculants can significantly increase soybean yield, thereby reducing dependence on nitrogen fertilizer during soybean production, improving soil health, and promoting green development in agriculture in the black soil region of Northeast China.

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BACKGROUND: Dry eye is a common eye disease. Artificial tears supplements are widely used for the treatment of dry eyes. However, multiple adverse effects have been observed in patients receiving long-term treatment with artificial tears, which may affect the therapeutic effect. AIM: To analyze the characteristics of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) levels in patients with dry eye and the therapeutic effect of artificial tears combined with cyclosporine A. METHODS: A total of 124 dry eye patients treated at The First People's Hospital of Xining from April 2020 to April 2022 were selected as the observation group, while 20 healthy individuals served as the control group during the same period. Levels of inflammatory markers, including IL-1ß, IL-6, and TNF-α, were analyzed. The observation group was further divided into a study group and a control group, each consisting of 62 patients. The control group received artificial tears, whereas the study group received a combination of artificial tears and cyclosporine A. Inflammatory markers, Schirmer's test (SIT), tear break-up time (TBUT), corneal fluorescein staining (CFS), National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25) scores, and adverse events (AEs) were compared between the two groups. RESULTS: The observation group exhibited significantly elevated serum levels of IL-1ß, IL-6, and TNF-α in comparison to the healthy group. Following treatment, the study group demonstrated substantial reductions in IL-1ß, IL-6, and TNF-α levels relative to the control group. Moreover, after treatment, the study group experienced a marked decrease in CFS scores and significant increases in both SIT and BUT levels when compared to the control group. Additionally, significant improvements were observed in the primary symptom of dry eye and secondary symptoms such as photophobia, foreign body sensation, fatigue, red eye, and burning sensation within the study group. Furthermore, post-treatment NEI-VFQ-25 scores across all dimensions exhibited significant enhancements in the study group compared to the control group (P < 0.05). It is noteworthy that significant AEs were reported in both groups throughout the treatment period. CONCLUSION: Cyclosporine A combined with artificial tears is effective in treating dry eye, yielding enhanced outcomes by improving SIT and TBUT levels, reducing CFS scores, and ameliorating vision-related quality of life.

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The aim of this study was to evaluate the accuracy of the JAMR upper-arm blood pressure monitor B23 in the general population according to the AAMI/ESH/ISO Universal Standard (ISO 81060-2 : 2018/AMD 1 : 2020). The study recruited participants who met the criteria of the AAMI/ESH/ISO Universal Standard in terms of their number, sex, age, limb size, and blood pressure (BP) distribution. The study involved measuring BP, including both SBP and DBP, using both the test device and a standard mercury sphygmomanometer in sequential measurements. Of 90 participants, 85 qualified participants were analyzed. A total of 255 sets of comparison data (three sets for each subject) were obtained and analyzed. For the validation criterion 1, the mean ±â€…SD of the differences between the JAMR B23 and mercury sphygmomanometer BP readings was -0.24 ±â€…6.52/-2.67 ±â€…5.6 mmHg (SBP/DBP). For criterion 2, the SD of the averaged BP (SBP/DBP) differences between the JAMR B23 and reference BP (SBP/DBP) per participant was 5.61/5.13 mmHg (the requirement was ≤6.95/6.43 mmHg by calculation). The JAMR B23 passed all the requirements of the AAMI/ESH/ISO Universal Standard (ISO 81060-2 : 2018/AMD 1 : 2020) and can be recommended for clinical and self/home use in the general population.

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The concentrations of atmospheric pollutants PM2.5, O3, SO2, NO2, and CO together with the meteorological factors of temperature （T）, relative humidity （RH）, wind speed, and other relevant data in Tangshan from 2015 to 2021 were collected to study the variation characteristics of PM2.5 and O3 at different periods in Tangshan City in the past seven years and their influencing factors, to discuss the contributions of air mass transport to PM2.5 and O3 pollution, and to reveal the synergistic influence mechanism of PM2.5 and O3 on atmospheric compound pollution by using correlation analysis and backward trajectory cluster analysis techniques. The results showed that PM2.5 concentrations in Tangshan decreased year by year from 2015 to 2021, whereas O3 concentration showed a unimodal trend, with the peak appearing in 2017. Both PM2.5 and O3 concentrations showed obvious seasonal variation trends； PM2.5 was characterized by the highest concentration in winter and the lowest concentration in summer, whereas O3 was characterized by the highest concentration in summer and the lowest concentration in winter. In addition, the diurnal variation in PM2.5 showed a bimodal distribution, with the peak occurring during the morning and evening on weekdays, and O3 showed a unimodal distribution, with the peak value appearing during the period with strong ultraviolet radiation in the afternoon. PM2.5 had a significant positive correlation with SO2, NO2, and CO, whereas O3 had a significant positive correlation with radiation and temperature. Under the different pollution conditions, PM2.5 and O3 were affected by air mass transports from different directions. Being impacted by various factors, the synergistic effect of PM2.5 and O3 on atmospheric compound pollution showed an obvious negative effect in winter, whereas there was an obvious positive effect in spring, summer, and autumn. Under the backgrounds of different pollutions, when the concentration of PM2.5 exceeded 150 µg·m-3, the synergistic effect of PM2.5 and O3 showed an obvious negative effect.

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Objective: This retrospective cohort study aimed to investigate the composition and diversity of lung microbiota in patients with severe pneumonia and explore its association with short-term prognosis. Methods: A total of 301 patients diagnosed with severe pneumonia underwent bronchoalveolar lavage fluid metagenomic next-generation sequencing (mNGS) testing from February 2022 to January 2024. After applying exclusion criteria, 236 patients were included in the study. Baseline demographic and clinical characteristics were compared between survival and non-survival groups. Microbial composition and diversity were analyzed using alpha and beta diversity metrics. Additionally, LEfSe analysis and machine learning methods were employed to identify key pathogenic microorganism associated with short-term mortality. Microbial interaction modes were assessed through network co-occurrence analysis. Results: The overall 28-day mortality rate was 37.7% in severe pneumonia. Non-survival patients had a higher prevalence of hypertension and exhibited higher APACHE II and SOFA scores, higher procalcitonin (PCT), and shorter hospitalization duration. Microbial α and ß diversity analysis showed no significant differences between the two groups. However, distinct species diversity patterns were observed, with the non-survival group showing a higher abundance of Acinetobacter baumannii, Klebsiella pneumoniae, and Enterococcus faecium, while the survival group had a higher prevalence of Corynebacterium striatum and Enterobacter. LEfSe analysis identified 29 distinct terms, with 10 potential markers in the non-survival group, including Pseudomonas sp. and Enterococcus durans. Machine learning models selected 16 key pathogenic bacteria, such as Klebsiella pneumoniae, significantly contributing to predicting short-term mortality. Network co-occurrence analysis revealed greater complexity in the non-survival group compared to the survival group, with differences in central genera. Conclusion: Our study highlights the potential significance of lung microbiota composition in predicting short-term prognosis in severe pneumonia patients. Differences in microbial diversity and composition, along with distinct microbial interaction modes, may contribute to variations in short-term outcomes. Further research is warranted to elucidate the clinical implications and underlying mechanisms of these findings.

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A Pd-catalyzed decarbonylative Michaelis-Arbuzov reaction of carboxylic acids and triaryl phosphites for preparing aryl phosphonates under anhydride-free conditions has been reported. In this context, triaryl phosphites serve as both reagents for activating the carboxylic acids and substrates for the reaction. There have been no reports to date of efficient and direct methods for the in situ activation of carboxylic acids using triaryl phosphites. In comparison to known methods, this reaction avoids the use of organohalides and has an excellent functional group tolerance for the synthesis of various aryl phosphonates from triaryl phosphites and carboxylic acids. This reaction is scalable and applicable to the synthesis of aryl phosphonates featuring bioactive fragments.

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Background: Hepatitis B virus-associated acute-on-chronic liver failure (HBV-ACLF) is a syn-drome with a high short-term mortality rate, and its prognosis is critical in clinical management. This study aimed to investigate the clinical significance of glutathione peroxidase 4 (GPX4) in the occurrence and development of HBV-ACLF and its prognostic value for 90-day mortality. Methods: The expression levels of GPX4, oxidative stress-related molecules and inflammatory cytokines in serum or peripheral blood mononuclear cells (PBMCs) of 289 participants were determined by RT-qPCR or ELISA, and the methylation level of GPX4 promoter in PBMCs was determined by MethyLight. Results: The expression levels of GPX4 in the PBMCs and serum of HBV-ACLF patients were lower than those in non-HBV-associated acute-on-chronic liver failure (non-HBV ACLF) patients, patients with chronic hepatitis B (CHB) and healthy control (HC) individuals, while the methylation level of the GPX4 promoter was greater. In HBV-ACLF patients, the methylation level of the GPX4 promoter is correlated with oxidative stress, inflammation-related molecules, and some clinicopathological indicators. The methylation level of the GPX4 promoter was identified as an independent risk factor for 90-day mortality in HBV-ACLF patients and yielded a larger area under the receiver operating characteristic curve (AUROC) than the model for end-stage liver disease (MELD) score in predicting 90-day mortality. Conclusion: The GPX4 promoter methylation level has promising potential as a predictor of 90-day mortality in patients with HBV-ACLF.

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The Yellow River Basin has been instrumental in advancing ecological preservation and fostering national high-quality development. However, since the advent of China's reform and opening-up policies, the basin has faced severe environmental pollution issues. This study leverages remote sensing data from 1998 to 2019. As per the "Basin Scope and Its Historical Changes" published by the Yellow River Conservancy Commission of the Ministry of Water Resources, the Yellow River Basin is categorized into upstream, midstream, and downstream regions for analysis of their spatial and temporal distribution traits using spatial autocorrelation methods. Additionally, we employed probes to study the effects of 10 factors, including mean surface temperature and air pressure, on PM2.5. The study findings reveal that (1) the annual average concentration of PM2.5 in the Yellow River Basin exhibited a fluctuating trend from 1998 to 2019, initially increasing, then decreasing, followed by another increase before ultimately declining. (2) The air quality in the Yellow River Basin is relatively poor, making it challenging for large-scale areas with low PM2.5 levels to occur. (3) The PM2.5 concentration in the Yellow River Basin exhibits distinct high and low-value concentration areas indicative of air pollution. Low-value areas are predominantly found in the sparsely populated central and southwestern plateau regions of Inner Mongolia, characterized by a better ecological environment. In contrast, high-value areas are prevalent in the inland areas of Northwest China, with poorer natural conditions, as well as densely populated zones with high energy demand and a relatively developed economy. (4) The overall population density in the Yellow River Basin, as well as in the upstream, midstream, and downstream regions, serves as a primary driving factor. (5) The primary drivers in the middle reaches and the entire Yellow River Basin remain consistent, whereas those in the upper and lower reaches have shifted. In the upstream, air pressure emerges as a primary driver of PM2.5, while in the downstream, NDVI and precipitation become the main influencing factors.

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Zhujiangyuan Nature Reserve, located in Qujing City, Yunnan Province, China, is reported with high fauna and floral diversity, while the fungal diversity of the region is poorly documented. During the summer season in 2023, decaying wood-inhabiting microfungi were collected from different microhabitats. The novel species were identified based on morphological characteristics and phylogenetic analyses (based on combined datasets of ITS, LSU, SSU, tef1-α, and rpb2 regions). Two species belong to Dothideomycetes (viz., Spegazziniazhujiangyuanensis sp. nov. and Phaeoseptumzhujiangyuanense sp. nov. in Pleosporales) while the other one resides in Sordariomycetes (Synnemasporellafanii sp. nov. in Diaporthales). The results are in conformity with the earlier studies that predicted higher fungal diversity in this region.

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Fowl cholera is an infectious disease that affects both poultry and wild birds, characterized by hemorrhagic and septicemic symptoms, caused by Pasteurella multocida (P. multocida), and leading to substantial economic losses in the poultry sector. The development of genetic engineering vaccines against avian P. multocida encountered early-stage challenges due to the limited availability of effective gene editing tools. Presently, NgAgoDM-enhanced homologous recombination stands as a potent technique for achieving efficient gene knockout in avian P. multocida. Hence, this study employed NgAgoDM-enhanced homologous recombination to target and knockout hyaE (239-359aa), hyaD, hexABC, and hexD, denoted as ΔhyaE (239-359aa), ΔhyaD, ΔhexABC, and ΔhexD, respectively. Additionally, we generated a hyaD recovery strain with two point mutations, designated as mhyaD. Thus, this study systematically examined the impact of capsular synthetic gene clusters on the pathogenicity of P. multocida. Moreover, the study demonstrated the critical role of hyaD activity in the virulence of avian P. multocida. This study offers novel insights for enhancing attenuated vaccines further.

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Commercially available rare-earth-doped inorganic oxide materials have been widely applied as X-ray scintillators, but the fragile characteristics, high detection limit, and harsh preparation condition seriously restrict their wide applications. Furthermore, it remains a huge challenge to realize X-ray flexible imaging technology for real-time monitoring of the curving interface of complex devices. To address these issues, we herein report two isostructural cuprous halides of zero-dimensional (0D) [AEPipz]CuX3·X·H2O (AEPipz = N-aminoethylpiperazine, X = Br and I) with controllable size to nanosize crystal as highly efficient scintillators toward flexible X-ray imaging. These cuprous halides exhibit highly efficient cyan photoluminescence and radioluminescence emissions with the highest quantum yield of 92.1% and light yield of 62,400 photons MeV-1, respectively, surpassing most of the commercially available inorganic scintillators. Meanwhile, the ultralow detection limit of 95.7 nGyair s-1 was far below the X-ray dose required for diagnosis (5.5 µGyair s-1). More significantly, the flexible film is facilely assembled with excellent foldability and high crack resistance, which further acts as a scintillation screen achieving a high spatial resolution of 17.4 lp mm-1 in X-ray imaging, demonstrating the potential application in wearable radiation radiography. The combined advantages of high light yield, low detection limit, and excellent flexibility promote these 0D cuprous halides as the most promising X-ray scintillators.

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PURPOSE: Using data from the National Health and Nutrition Examination Survey (NHANES) and employing Controlled Attenuation Parameter (CAP) measures, this study explores the correlation between vitamin E (VE) intake and hepatic steatosis and its impact on different subsets. MATERIALS AND METHODS: We selected 5757 participants with CAP data from the 2017-2020 NHANES dataset. Daily VE intake was assessed by a 24-hour dietary recall. Hepatic fat content was quantified using transient elastography to measure CAP. Stratified multivariable regression analysis investigated relationships in different subsets, and a generalized additive model identified nonlinear relationships and thresholds. RESULTS: After adjusting for confounders, higher VE intake correlated with lower CAP levels. Subgroup analyses and tests for interaction revealed a significantly stronger negative correlation between VE intake and CAP in obese individuals. Further analysis indicated a curvilinear relationship between VE intake and the severity of liver fat degeneration in both the general study population and the obese subgroup, demonstrating a threshold effect. In the general population, VE intake below the threshold (6.58 mg/day) is positively correlated with CAP levels, whereas intake above this threshold shows a negative correlation. For obese individuals, the threshold is set at 7.37 mg/day, above which the negative correlation with CAP is even more pronounced. CONCLUSION: Our study revealed a negative correlation between VE intake and hepatic fat content, highlighting the potentially crucial role VE plays in obese fatty liver patients. Importantly, we identified threshold effects of VE intake in both general and obese populations. Our results support clinical nutritional interventions, personalized dietary guidance, and the development of drugs to combat fatty liver.

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Magnaporthe oryzae (M. oryzae) is a devastating hemibiotrophic pathogen. Its biotrophic invasive hyphae (IH) are enclosed in the extrainvasive hyphal membrane produced by plant cells, thus generating a front line of the battlefield between the pathogen and the host plants. In plants, defense-related complexes such as proteins, callose-rich materials and vesicles, are directionally secreted to this interface to confer defense responses, but the underlying molecular mechanism is poorly understood. In this study, we found that a Myosin gene, Myosin A1 (OsMYA1), contributed to rice defense. The OsMYA1 knockout mutant exhibited decreased resistance to M. oryzae infection. OsMYA1 localizes to the actin cytoskeleton and surrounds the IH of M. oryzae. OsMYA1 interacts with an exocyst subunit, OsExo70H1, and regulates its accumulation at the plasma membrane (PM) and pathogen-plant interface. Furthermore, OsExo70H1 interacted with the rice syntaxin of the plants121 protein (OsSyp121), and the distribution of OsSyp121 to the PM or the pathogen-plant interface was disrupted in both the OsMYA1 and OsExo70H1 mutants. Overall, these results not only reveal a new function of OsMYA1 in rice blast resistance, but also uncover a molecular mechanism by which plants regulate defense against M. oryzae by OsMYA1-initiated vesicle secretory pathway, which originates from the actin cytoskeleton to the PM.

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To investigate atropisomers of non-steroidal glucocorticoid receptor modulator GSK866, a virtual library of substituted benzoic acid analogues was enumerated. Compounds from this library were subjected to a torsion angle scan using Spartan'20 to calculate the torsion rotation energy barrier which identified compounds predicted to be stable as atropisomers. After synthesis of the library, analysis showed that compounds 13 and 14 existed as stable atropisomers 13a, 13b, 14a and 14b, in agreement with the earlier calculations. Screening in a glucocorticoid receptor cellular assay showed that one compound from each atropisomer pair was significantly more potent than the other. Docking in a public structure of the glucocorticoid receptor (PBD code 3E7C) enabled the stereochemistry of the two most potent compounds 13a and 14b to be assigned as (R a) and (S a), respectively.

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Atmospheric precipitation samples were collected in 2018, 2019, and 2021 in Beijing to study the concentrations and changes of the main metal elements and water-soluble ions； the wet deposition fluxes of heavy metals, water-soluble ions, dissolved inorganic nitrogen, and sulfur in the atmospheric precipitation and their impacts on the ecological environment； and the scavenging mechanisms of the typical precipitation to atmospheric pollutants during the study period. The results showed that the precipitation in Beijing during the study period was mostly neutral or alkaline, and the frequency of acid rain occurrence was very low, only accounting for 3.06%. The total concentrations of major metal elements in 2018, 2019, and 2021 were （4 787.46 ±4 704.31）, （7 663.07 ±8 395.05）, and （2 629.13 ±2 369.51） µg·L-1, respectively. The total equivalent concentrations of ions in 2018, 2019, and 2021 were （851.68 ±649.16）, （973.98 ±850.94）, and （644.31 ±531.16） µeq·L-1, respectively. The interannual changes in major metal elements and ions followed the order of 2019 > 2018 > 2021. The seasonal average total concentrations of major metal elements in spring, summer, autumn, and winter were （9 624.25 ±7 327.92）, （4 088.67 ±5 710.14）, （3 357.68 ±3 995.64）, and （6 203.19 ±3 857.43） µg·L-1, respectively, and the seasonal average total equivalent concentrations of ions in spring, summer, autumn, and winter were （1 014.71 ±512.21）, （729.83 ±589.90）, （724.35 ±681.40）, and （1 014.03 ±359.67） µeq·L-1, respectively, all presenting the order of spring > winter > summer > autumn. NO3- and SO42- were the main acid-causing ions in precipitation, whereas NH4+ and Ca2+ were the main acid-neutralizing ions. The wet deposition fluxes of the heavy metal Cd were very low [（0.05 ±0.01） mg·ï¼ˆm2·a）-1], only accounting for （0.13 ±0.04）% of the total wet deposition fluxes of main metal elements； however, its soil safety years were 291 years, significantly lower than those of other heavy metals, displaying that its ecological risk was relatively the highest. The total wet precipitation flux of water-soluble ions NH4+, Ca2+, NO3-, and SO42- accounted for （85.72 ±2.18）% of the wet precipitation flux of total ions, suggesting that their comprehensive impact on the ecological environment might have been higher. DIN wet deposition flux was mainly characterized by NH4+-N, which had a positive impact on the ecological environment in summer. SO42--S wet deposition flux was higher in summer, so its positive impact on the ecological environment was also greater. The scavenging effects of atmospheric precipitations to pollutants from the air were impacted by various factors, and the synergism effects of these factors could directly influence the scavenging mechanisms of precipitation to pollutants.

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In order to understand the stability of the zooplankton and phytoplankton communities in the Guizhou plateau reservoir environment, the process of reservoir water quality change affecting the stability of plankton was studied. The changes in the plankton community and water quality in three different nutrient reservoirs （Huaxi Reservoir, Goupitan Reservoir, and Hailong Reservoir） were studied from October 2020 to August 2021. The stability of the zooplankton and phytoplankton communities was studied using time-lag analysis （TLA）. Variance decomposition analysis （VPA） was used to explore the response of the two communities to environmental changes. The driving factors of plankton community changes in reservoirs were also revealed. The results showed that Huaxi Reservoir and Goupitan Reservoir were mesotrophic reservoirs, and Hailong Reservoir was a eutrophic reservoir. The average comprehensive nutrition indices of the three reservoirs were 44.07, 44.68, and 50.25. A total of 51 species of zooplankton rotifers, 39 species of rotifers, three species of copepods, and nine species of cladocera were identified. Among them, the abundance of rotifers was the highest, accounting for 85.96%. A total of seven phyla and 73 species of phytoplankton were identified, including 16 species in the phylum Cyanophyta, 32 species in the phylum Chlorophyta, 16 species in the phylum Diatoma, three species in the phylum Chlorophyta, four species in the phylum Euglenophyta, and one species each in the phyla Cryptophyta and Chrysophyta. Among them, the abundance of cyanobacteria and diatoms was the highest, accounting for 66.2% and 27.35%, respectively. The median absolute deviation （MAD） of the Bray-Curtis distance of zooplankton and phytoplankton community in the three reservoirs were 0.67 and 0.65 in Huaxi Reservoir, 0.80 and 0.69 in Goupitan Reservoir, and 0.85 and 0.47 in Hailong Reservoir, respectively. The larger the value, the greater the variation in the community. The absolute value of the slope of zooplankton was greater than that of phytoplankton in the TLA results, and the absolute values of the slopes were 0.018 and 0.004, respectively. The larger the absolute value of the slope, the faster the community variability. The zooplankton community in the three reservoirs was less stable than the phytoplankton community and more sensitive to environmental changes, and the degree of variation was greater. The higher the degree of eutrophication of the reservoir, the more obvious this phenomenon. VPA showed that the changes in plankton communities in Huaxi Reservoir and Hailong Reservoir were mainly influenced by water temperature and eutrophication factors. The changes in planktonic community in Goupitan Reservoir were mainly influenced by water temperature and chemical factors. The driving factors of Huaxi Reservoir were water temperature, TP, permanganate index, and SD. The driving factors of Goupitan Reservoir were water temperature, NO3-- N, and pH. The driving factors of Hailong Reservoir were water temperature and TP. Nutrients and water temperature were the main factors affecting the stability of plankton communities in reservoirs.

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