Metabolomics reveals the importance of metabolites in Mussaenda pubescens for antioxidant properties and quality traits.

Mussaenda pubescens (Mp) is a valuable medicinal plant that has traditionally been used for medicinal purposes or as a tea substitute. However, there are few studies on the comprehensive and dynamic evaluation of Mp metabolites. This study used an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) approach and biochemical analysis to investigate substance changes in leaves at three different stages and elucidate the relationship between metabolites and antioxidant capacity. The findings showed that Mp leaves contained 957 metabolites, the majority of which were phenolic acids, lipids, and terpenoids. The metabolite profiling of Mp leaves was significantly influenced by their growth and development at different stages. A total of 317 differentially accumulated metabolites (DAMs) were screened, including 150 primary metabolites and 167 secondary metabolites, with 202 DAMs found in bud leaf vs. tender leaf, 54 DAMs in tender leaf vs. mature leaf, and 254 DAMs in bud leaf vs. mature leaf. Total phenolics, flavonoids, and anthocyanin concentrations decreased as Mp leaves grew and developed, whereas terpenoids increased significantly. The secondary metabolites also demonstrated a positive correlation with antioxidant activity. Phenolics, flavonoids, terpenoids, and anthocyanins were the primary factors influencing the antioxidant activity of leaves. These findings provide new insights into the metabolite formation mechanism, as well as the development and utilization of Mp tea.

The Changes in Metabolites, Quality Components, and Antioxidant Activity of Tea (Camellia sinensis) Infected with Exobasidium vexans by Applying UPLC-MS/MS-Based Widely Targeted Metabolome and Biochemical Analysis.

Blister blight infection with Exobasidium vexans is one of the most destructive foliar diseases that seriously affect the quality and yield of tea. This research investigated the metabolite changes of healthy and infected leaves on tea cultivar 'Fuding Dabaicha' and further explored the potential antimicrobial substances against E. vexans infection. In total, 1,166 compounds were identified during the entire course of an infection, among which 73 different common compounds were significantly accumulated involved in the important antimicrobial substances of flavonoids and phenolic acids, including kaempferol (3,5,7,4'-tetrahydroxyflavone), kaempferol-3-O-sophoroside-7-O-glucoside, phloretin, 2,4,6-trihydroxybenzoic acid, galloylprocyanidin B4, and procyanidin C1 3'-O-gallate, which indicated that these metabolites might positively dominate resistance to E. vexans. Furthermore, relevant biological pathways, such as the flavone and flavonol biosynthesis, flavonoid biosynthesis, and phenylpropane pathways, were more closely related to resistance to E. vexans. Additionally, total flavonoids, phenolics, alkaloids, and terpenoids contributing to antimicrobial and antioxidant capacity were significantly altered during four different infection periods, especially the Leaf_S2 stage (the second stage of infection), in which the most concentration accumulated. The leaves affected by E. vexans infection at the second stage had the relatively highest antioxidant activity. Accordingly, this study provides a theoretical support for and comprehensive insights into the effects on the metabolite changes, tea quality components, and antioxidant activity of blister blight caused by E. vexans.

Polymerization Based on Modified ß-Cyclodextrin Achieves Efficient Phosphorescence Energy Transfer for Anti-Counterfeiting.

Supramolecular polymerization can not only activate guest phosphorescence, but also promote phosphorescence Förster resonance energy transfer and induce effective delayed fluorescence. Herein, the solid supramolecular assemblies of ternary copolymers based on acrylamide, modified ß-cyclodextrin (CD), and carbazole (CZ) are reported. After doping with polyvinyl alcohol (PVA) and dyes, a NIR luminescence supramolecular composite with a lifetime of 1.07 s, an energy transfer efficiency of up to 97.4% is achieved through tandem phosphorescence energy transfer. The ternary copolymers can realize macrocyclic enrichment of dyes in comparison to CZ and acrylamide copolymers without CD, which can facilitate energy transfer between triplet and singlet with a high donor-acceptor ratio. Additionally, the flexible polymeric films exhibit regulable lifetime, tunable luminescence color, and repeatable switchable afterglow by adjusting the excitation wavelength, donor-acceptor ratio, and wet/dry stimuli. The luminescence materials are successfully applied to information encryption and anti-counterfeiting.

Duyun compound green tea extracts regulate bile acid metabolism on mice induced by high-fat diet.

Duyun compound green tea (DCGT) is a healthy beverage with lipid-lowering effect commonly consumed by local people, but its mechanism is not very clear. We evaluated the effect of DCGT treatment on bile acids (BA) metabolism of mice with high-fat diet (HFD) - induced hyperlipidaemia by biochemical indexes and metabolomics and preliminarily determined the potential biomarkers and metabolic pathways of hyperlipidaemia mice treated with DCGT as well as investigated its lipid-lowering mechanism. The results showed that DCGT treatment could reduce HFD - induced gain in weight and improve dyslipidaemia. In addition, a total of ten types of BA were detected, of which seven changed BA metabolites were observed in HFD group mice. After DCGT treatment, glycocholic acid, tauroursodeoxycholic acid and taurochenodeoxycholic acid were significantly down-regulated, while hyodeoxycholic acid, deoxycholic acid and chenodeoxycholic acid were markedly up-regulated. These results demonstrated that DCGT treatment was able to make the BA metabolites in the liver of hyperlipidaemia mice normal and alleviate hyperlipidaemia by regulating the metabolites such as glycocholic acid, tauroursodeoxycholic acid and taurochenodeoxycholic, as well as the BA metabolic pathway and cholesterol metabolic pathway involved.

Satellite monitoring reveals short-term cumulative and time-lag effect of drought and heat on autumn photosynthetic phenology in subtropical vegetation.

Comparing with the effect of the average climate change on vegetation phenology, the impacts of extreme climate events remain unclear, especially considering their characteristic cumulative and time-lag effects. Using solar-induced chlorophyll fluorescence (SIF) satellite records, we investigated the cumulative and time-lag effects of drought and heat events on photosynthesis, particularly for the end date of autumn photosynthesis (EOP), in subtropical vegetation in China. Our results showed a negative effect of drought on the delay of EOP, with the cumulative effect on 30.12% (maximum continuous dry days, CDD), 34.82% (dry days, DRD), and 26.14% (dry period, DSDI) of the study area and the general time-lag effect on 50.73% (maximum continuous dry days), 56.61% (dry days), and 47.55% (dry period) of the study area. The cumulative and lagged time were 1-3 months and 2-3 months, respectively. In contrast, the cumulative effect of heat on EOP was observed in 16.27% (warm nights, TN90P), 23.66% (moderate heat days, TX50P), and 19.19% (heavy heat days, TX90P) of the study area, with cumulative time of 1-3 months. The lagged time was 3-4 months, detected in 31.02% (warm nights), 45.86% (moderate heat days), and 36.52% (heavy heat days) of the study area. At the vegetation community level, drought and heat had relatively rapid impacts on EOP in the deciduous broadleaved forest, whereas evergreen forests and bushes responded to heat slowly and took a longer time. Our results revealed that drought and heat have short-term cumulative and time-lag effects on the EOP of subtropical vegetation in China, with varying effects among different vegetation types. These findings provide new insights into the effect of drought and heat on subtropical vegetation and confirm the need to consider these effects in the development of prediction models of autumn phenology for subtropical vegetation.

Diagnostic value of X-ray, endoscopy, and high-resolution manometry for hiatal hernia: A systematic review and meta-analysis.

BACKGROUND AND AIM: Hiatal hernia (HH) has been found in a large number of people, but there has been no unified way to diagnose it. The aim of this study was to compare the diagnostic efficiency of X-ray, endoscopy, and high-resolution manometry (HRM) in the diagnosis of HH using surgical diagnosis of HH as the gold standard. METHODS: Two biomedical databases (PubMed and EMBASE) were systematically searched through January 26, 2019. The pooled sensitivity, specificity, and area under the SROC curve (AUC) were calculated, and the AUC statistical significance was compared by Tukey's multiple comparisons test. RESULTS: A total of 5337 patients in seven articles were included. The pooled sensitivity, specificity, and AUC for X-ray were 0.63 (0.46-0.77), 0.85 (0.69-0.94), and 0.80 (0.77-0.84), respectively, for diagnosing HH. The pooled estimates for endoscopy in diagnosing HH were as follows: sensitivity, 0.72 (0.39-0.91); specificity, 0.80 (0.70-0.87); and AUC, 0.82 (0.78-0.85). Similarly, the corresponding values for HRM were 0.77 (0.70-0.83); 0.92 (0.85-0.96), and 0.9527. Tukey's multiple comparisons tests were used to compare the AUCs of the three diagnostic methods: No significant differences were found between X-ray and endoscopy (P = 0.7293), and HRM was superior to X-ray (P = 0.0127) and endoscopy (P = 0.0442). CONCLUSIONS: High-resolution manometry may exhibit a better diagnostic performance for hiatal hernia. In contrast, X-ray and endoscopy may not be the best methods, and there was no significant difference in diagnostic efficiency between the X-ray and endoscopy.

Marek's Disease Virus Regulates the Ubiquitylome of Chicken CD4+ T Cells to Promote Tumorigenesis.

Ubiquitination and deubiquitination of cellular proteins are reciprocal reactions catalyzed by ubiquitination-related enzymes and deubiquitinase (DUB) which regulate almost all cellular processes. Marek's disease virus (MDV) encodes a viral DUB that plays an important role in the MDV pathogenicity. Chicken CD4+ T-cell lymphoma induced by MDV is a key contributor to multiple visceral tumors and immunosuppression of chickens with Marek's disease (MD). However, alterations in the ubiquitylome of MDV-induced T lymphoma cells are still unclear. In this study, a specific antibody against K-ε-GG was used to isolate ubiquitinated peptides from CD4+ T cells and MD T lymphoma cells. Mass spectrometry was used to compare and analyze alterations in the ubiquitylome. Our results showed that the ubiquitination of 717 and 778 proteins was significantly up- and downregulated, respectively, in T lymphoma cells. MDV up- and downregulated ubiquitination of a similar percentage of proteins. The ubiquitination of transferases, especially serine/threonine kinases, was the main regulatory target of MDV. Compared with CD4+ T cells of the control group, MDV mainly altered the ubiquitylome associated with the signal transduction, immune system, cancer, and infectious disease pathways in T lymphoma cells. In these pathways, the ubiquitination of CDK1, IL-18, PRKCB, ETV6, and EST1 proteins was significantly up- or downregulated as shown by immunoblotting. The current study revealed that the MDV infection could exert a significant influence on the ubiquitylome of CD4+ T cells.

Olfactory reference syndrome symptoms in Chinese university students: Phenomenology, associated impairment, and clinical correlates.

BACKGROUND: The present study aimed to explore the phenomenology, associated impairment, and clinical correlates of olfactory reference syndrome (ORS) symptoms in a Chinese university student sample, and establish estimated ORS prevalence. METHODS: A total of 421 undergraduate students completed self-report measures assessing symptoms of ORS, obsessive-compulsive disorder, depression, anxiety, stress, taijin kyofushu, fear of negative evaluation, and ORS-related functional impairment. RESULTS: Higher ORS symptom severity was moderately associated with poorer insight, greater avoidance, and higher ORS-related functional impairment. ORS severity was weakly associated with increased comorbid disorder symptoms, and was not associated with gender. Clinically significant ORS symptoms were present in 2.4% of the sample. DISCUSSION: Collectively, these findings suggest that ORS symptoms are relatively distinct from other disorders in a non-clinical sample. Future studies are encouraged to further explore the phenomenology, etiology, neurobiology, and treatment of ORS in order to inform diagnosis and nosology.

Quantifying multi-dimensional attributes of human activities at various geographic scales based on smartphone tracking.

BACKGROUND: Advancement in location-aware technologies, and information and communication technology in the past decades has furthered our knowledge of the interaction between human activities and the built environment. An increasing number of studies have collected data regarding individual activities to better understand how the environment shapes human behavior. Despite this growing interest, some challenges exist in collecting and processing individual's activity data, e.g., capturing people's precise environmental contexts and analyzing data at multiple spatial scales. METHODS: In this study, we propose and implement an innovative system that integrates smartphone-based step tracking with an app and the sequential tile scan techniques to collect and process activity data. We apply the OpenStreetMap tile system to aggregate positioning points at various scales. We also propose duration, step and probability surfaces to quantify the multi-dimensional attributes of activities. RESULTS: Results show that, by running the app in the background, smartphones can measure multi-dimensional attributes of human activities, including space, duration, step, and location uncertainty at various spatial scales. By coordinating Global Positioning System (GPS) sensor with accelerometer sensor, this app can save battery which otherwise would be drained by GPS sensor quickly. Based on a test dataset, we were able to detect the recreational center and sports center as the space where the user was most active, among other places visited. CONCLUSION: The methods provide techniques to address key issues in analyzing human activity data. The system can support future studies on behavioral and health consequences related to individual's environmental exposure.

Interannual variation in methane emissions from tropical wetlands triggered by repeated El Niño Southern Oscillation.

Methane (CH4 ) emissions from tropical wetlands contribute 60%-80% of global natural wetland CH4 emissions. Decreased wetland CH4 emissions can act as a negative feedback mechanism for future climate warming and vice versa. The impact of the El Niño-Southern Oscillation (ENSO) on CH4 emissions from wetlands remains poorly quantified at both regional and global scales, and El Niño events are expected to become more severe based on climate models' projections. We use a process-based model of global wetland CH4 emissions to investigate the impacts of the ENSO on CH4 emissions in tropical wetlands for the period from 1950 to 2012. The results show that CH4 emissions from tropical wetlands respond strongly to repeated ENSO events, with negative anomalies occurring during El Niño periods and with positive anomalies occurring during La Niña periods. An approximately 8-month time lag was detected between tropical wetland CH4 emissions and ENSO events, which was caused by the combined time lag effects of ENSO events on precipitation and temperature over tropical wetlands. The ENSO can explain 49% of interannual variations for tropical wetland CH4 emissions. Furthermore, relative to neutral years, changes in temperature have much stronger effects on tropical wetland CH4 emissions than the changes in precipitation during ENSO periods. The occurrence of several El Niño events contributed to a lower decadal mean growth rate in atmospheric CH4 concentrations throughout the 1980s and 1990s and to stable atmospheric CH4 concentrations from 1999 to 2006, resulting in negative feedback to global warming.

Regional drought-induced reduction in the biomass carbon sink of Canada's boreal forests.

The boreal forests, identified as a critical "tipping element" of the Earth's climate system, play a critical role in the global carbon budget. Recent findings have suggested that terrestrial carbon sinks in northern high-latitude regions are weakening, but there has been little observational evidence to support the idea of a reduction of carbon sinks in northern terrestrial ecosystems. Here, we estimated changes in the biomass carbon sink of natural stands throughout Canada's boreal forests using data from long-term forest permanent sampling plots. We found that in recent decades, the rate of biomass change decreased significantly in western Canada (Alberta, Saskatchewan, and Manitoba), but there was no significant trend for eastern Canada (Ontario and Quebec). Our results revealed that recent climate change, and especially drought-induced water stress, is the dominant cause of the observed reduction in the biomass carbon sink, suggesting that western Canada's boreal forests may become net carbon sources if the climate change-induced droughts continue to intensify.

The integration of geographic methods and ecological momentary assessment in public health research: A systematic review of methods and applications.

With the widespread prevalence of mobile devices, ecological momentary assessment (EMA) can be combined with geospatial data acquired through geographic techniques like global positioning system (GPS) and geographic information system. This technique enables the consideration of individuals' health and behavior outcomes of momentary exposures in spatial contexts, mostly referred to as "geographic ecological momentary assessment" or "geographically explicit EMA" (GEMA). However, the definition, scope, methods, and applications of GEMA remain unclear and unconsolidated. To fill this research gap, we conducted a systematic review to synthesize the methodological insights, identify common research interests and applications, and furnish recommendations for future GEMA studies. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines to systematically search peer-reviewed studies from six electronic databases in 2022. Screening and eligibility were conducted following inclusion criteria. The risk of bias assessment was performed, and narrative synthesis was presented for all studies. From the initial search of 957 publications, we identified 47 articles included in the review. In public health, GEMA was utilized to measure various outcomes, such as psychological health, physical and physiological health, substance use, social behavior, and physical activity. GEMA serves multiple research purposes: 1) enabling location-based EMA sampling, 2) quantifying participants' mobility patterns, 3) deriving exposure variables, 4) describing spatial patterns of outcome variables, and 5) performing data linkage or triangulation. GEMA has advanced traditional EMA sampling strategies and enabled location-based sampling by detecting location changes and specified geofences. Furthermore, advances in mobile technology have prompted considerations of additional sensor-based data in GEMA. Our results highlight the efficacy and feasibility of GEMA in public health research. Finally, we discuss sampling strategy, data privacy and confidentiality, measurement validity, mobile applications and technologies, and GPS accuracy and missing data in the context of current and future public health research that uses GEMA.

Interoception, somatic symptoms, and somatization tendency in Chinese individuals with subsyndromal depression: A follow-up study.

Interoception refers to the sensation and perception of internal bodily sensations, and may be related to depressive symptoms. Schemata concerning the body vary across different cultures and may influence interoception and symptom presentations of depression. This study explored the relationship between interoception, depressive symptoms, and schema of somatic focus in Chinese people with subsyndromal depression. Thirty-nine individuals with subsyndromal depression (SD) and 40 healthy controls (HCs) were assessed at baseline and after 3 months. Participants completed the self-report questionnaires for assessing interoceptive sensibility, somatic and psychological symptoms of depression, and somatization tendency. They also completed the heartbeat perception behavioral task for estimating interoceptive accuracy. The results showed that both the SD and the HC groups showed similar interoceptive accuracy, although the SD group showed heightened interoceptive sensibility. The discrepancy between interoceptive sensibility and interoceptive accuracy is termed the interoceptive trait prediction error (ITPE). The ITPE was positive in SD participants but was negative in HCs. In the entire sample, interoceptive sensibility and the ITPE were correlated with somatic symptoms rather than with psychological symptoms of depression. Interoceptive sensibility partially mediated the relationship between somatization tendency and somatic symptoms, after controlling for psychological symptoms of depression. These results remained stable after 3 months. The shortcomings of the present study were a lack of clinical interview to ascertain diagnosis and a short follow-up duration. In conclusion, our study suggests that altered interoception occurs in subsyndromal depression. Interoception is related to somatic symptoms of depression. The schema of body was related to depressive symptoms, partially through interoception, in Chinese people with subsyndromal depression.

The complete chloroplast genome of Mussaenda pubescens and phylogenetic analysis.

The chloroplast (cp) genome sequence of Mussaenda pubescens, a promising resource that is used as a traditional medicine and drink, is important for understanding the phylogenetic relationships among the Mussaenda family and genetic improvement and reservation. This research represented the first comprehensive description of the morphological characteristics of M. pubescens, as well as an analysis of the complete cp genome and phylogenetic relationship. The results indicated a close relationship between M. pubescens and M. hirsutula based on the morphological characteristics of the flower and leaves. The cp was sequenced using the Illumina NovaSeq 6000 platform. The results indicated the cp genome of M. pubescens spanned a total length of 155,122 bp, including a pair of inverted repeats (IRA and IRB) with a length of 25,871 bp for each region, as well as a large single-copy (LSC) region and a small single-copy (SSC) region with lengths of 85,370 bp and 18,010 bp, respectively. The results of phylogenetic analyses demonstrated that species within the same genus displayed a tendency to group closely together. It was suggested that Antirhea, Cinchona, Mitragyna, Neolamarckia, and Uncaria might have experienced an early divergence. Furthermore, M. hirsutula showed a close genetic connection to M. pubescens, with the two species having partially overlapping distributions in China. This study presents crucial findings regarding the identification, evolution, and phylogenetic research on Mussaenda plants, specifically targeting M. pubescens.

Identification and molecular docking of xanthine oxidase and α-glucosidase inhibitors in Opuntia ficus-indica fruit.

Opuntia ficus-indica fruit (OFI) is rich in bioactive compounds, which can promote human health. In this work, the purified OFI extract was prepared from OFI and its bioactivities were investigated. Xanthine oxidase (XOD) and α-glucosidase (α-Glu) inhibitors of the purified OFI extract were screened and identified by bio-affinity ultrafiltration combined with UPLC-QTRAP-MS/MS technology. The inhibitory effect of these inhibitors on enzymes were verified, and the potential mechanism of action and binding sites of inhibitors with enzymes were revealed based on molecular docking. The results showed that the total phenolic content of the purified OFI extract was 355.03 mg GAE/g DW, which had excellent antioxidant activity. Additionally, the extract had a certain inhibitory effect on XOD (IC50 = 199.00 ± 0.14 µg/mL) and α-Glu (IC50 = 159.67 ± 0.01 µg/mL). Seven XOD inhibitors and eight α-Glu inhibitors were identified. Furthermore, XOD and α-Glu inhibition experiments in vitro confirmed that inhibitors such as chlorogenic acid, taxifolin, and naringenin had significant inhibitory effects on XOD and α-Glu. The molecular docking results indicated that inhibitors could bind to the corresponding enzymes and had strong binding force. These findings demonstrate that OFI contains potential substances for the treatment of hyperuricemia and hyperglycemia.

Supramolecular assembly activated single-molecule phosphorescence resonance energy transfer for near-infrared targeted cell imaging.

Pure organic phosphorescence resonance energy transfer is a research hotspot. Herein, a single-molecule phosphorescence resonance energy transfer system with a large Stokes shift of 367 nm and near-infrared emission is constructed by guest molecule alkyl-bridged methoxy-tetraphenylethylene-phenylpyridines derivative, cucurbit[n]uril (n = 7, 8) and ß-cyclodextrin modified hyaluronic acid. The high binding affinity of cucurbituril to guest molecules in various stoichiometric ratios not only regulates the topological morphology of supramolecular assembly but also induces different phosphorescence emissions. Varying from the spherical nanoparticles and nanorods for binary assemblies, three-dimensional nanoplate is obtained by the ternary co-assembly of guest with cucurbit[7]uril/cucurbit[8]uril, accompanying enhanced phosphorescence at 540 nm. Uncommonly, the secondary assembly of ß-cyclodextrin modified hyaluronic acid and ternary assembly activates a single intramolecular phosphorescence resonance energy transfer process derived from phenyl pyridines unit to methoxy-tetraphenylethylene function group, enabling a near-infrared delayed fluorescence at 700 nm, which ultimately applied to mitochondrial targeted imaging for cancer cells.

Analysis of long-term spatio-temporal changes of plateau urban wetland reveals the response mechanisms of climate and human activities: A case study from Dianchi Lake Basin 1993-2020.

Wetlands serve many functions, including conserving water, providing habitats for animals and plants, and regulating climate change. Their unique ecological effects on the natural environment are indispensable in the whole ecosystem. Dianchi Lake Basin is located in Yunnan-Guizhou Plateau, China, and mainly in Kunming. It is a typical plateau urban wetland area. Based on spatio-temporal hotspot mining, spatio-temporal geographically weighted regression, and adaptive multidimensional grey prediction, we conducted correlation analyses of the wetland changes in Dianchi Lake Basin from 1993 to 2020 under the influence of human activities and natural conditions. The results show that (1) the active wetland change zone in Dianchi Lake Basin is mainly located around Dianchi Lake, and (2) the wetlands in some areas on the north and south of Dianchi Lake declined in the early 21st century, but under the protection policy in recent years, the wetlands in these areas gradually recovered. Meanwhile, the wetlands in most areas around Dianchi Lake showed a significant growth trend from 2018 to 2020. The results suggest that the wetland change in Dianchi Lake Basin is mainly related to the urbanization of Kunming, and it can be divided into five regions (strong negative correlation, weak negative correlation, weak correlation, weak positive correlation, and strong positive correlation) according to the different correlation of human activity intensity, among which the main factors affected by nature are different, but they are all related to temperature. This study shows that, although wetlands in plateau cities can be properly restored under proper protection, wetland protection should be kept in step with the development of plateau cities to support sustainable urban development and carbon neutrality.

Response of changes in lake area to drought and land use change.

The lake area is a crucial parameter that characterizes the state of a lake. Under the dual pressures of climate change and human activity, the magnitude and frequency of changes in lake areas become more pronounced. This process poses a serious threat to the local ecological environment. In this study, we constructed a lake water extraction model (LakeNet) based on a fully convolutional neural network. We extracted and analyzed the spatiotemporal characteristics of the area of nine major lakes from 1987 to 2022, as well as the driving factors behind these changes. Our results indicate that: 1) LakeNet exhibits high extraction accuracy and can remove some clouds. 2) The area of the nine major lakes shows a fluctuating downward trend (-8.11km2/10a), with drought and land use changes identified as significant driving forces behind the changes in lake boundaries, drought events caused the lake area to decrease, and the expansion of cropland further reduced the lake area. 3) Due to variations in lake area, the impact of drought on the area of the nine major lakes exhibits a lag effect, smaller lakes are likely to respond more quickly to drought.

Enhanced cycloaddition between CO2 and epoxide over a bismuth-based metal organic framework due to a synergistic photocatalytic and photothermal effect.

The cycloaddition reaction between CO2 and epoxide is an efficient way to convert CO2 into high value-added chemicals. Therefore, it is particularly important to develop efficient catalysts that can catalyze the reaction under mild conditions. In this work, a metal-organic framework (Bi-HHTP, consisting of bismuth (Bi) as metal dots and 2,3,6,7,10,11-hexahydroxy-triphenylene (HHTP) as organic linkers) with zigzagging corrugated topology was successfully synthesized, which shows excellent catalytic activity under visible light irradiation. Various characterizations suggest that the excellent activity is derived from the following reasons: (1) the abundant exposed Bi sites provide Lewis sites for adsorption of epoxides and CO2; (2) the free holes produced over Bi-HHTP under light irradiation which could oxidize epoxide, which consequently facilitateing the subsequent ring-opening reaction; and (3) the existence of synergistic photocatalytic and photothermal effect in Bi-HHTP. This study provides a new avenue of developing bismuth-based metal organic frameworks to promote the efficiency of cycloaddition of CO2 under mild conditions.

Phenolic compounds weaken the impact of drought on soil enzyme activity in global wetlands.

Soil enzymes play a central role in carbon and nutrient cycling, and their activities can be affected by drought-induced oxygen exposure. However, a systematic global estimate of enzyme sensitivity to drought in wetlands is still lacking. Through a meta-analysis of 55 studies comprising 761 paired observations, this study found that phosphorus-related enzyme activity increased by 38% as result of drought in wetlands, while the majority of other soil enzyme activities remained stable. The expansion of vascular plants under long-term drought significantly promoted the accumulation of phenolic compounds. Using a 2-week incubation experiment with phenol supplementation, we found that phosphorus-related enzyme could tolerate higher biotoxicity of phenolic compounds than other enzymes. Moreover, a long-term (35 years) drainage experiment in a northern peatland in China confirmed that the increased phenolic concentration in surface layer resulting from a shift in vegetation composition inhibited the increase in enzyme activities caused by rising oxygen availability, except for phosphorus-related enzyme. Overall, these results demonstrate the complex and resilient nature of wetland ecosystems, with soil enzymes showing a high degree of adaptation to drought conditions. These new insights could help evaluate the impact of drought on future wetland ecosystem services and provide a theoretical foundation for the remediation of degraded wetlands.