Lead-halide perovskite nanoparticles(LHP NPs) are highly promising materials for next-generation displays and solid-state lighting due to their exceptional optical properties. However, their inherent instability prese...Lead-halide perovskite nanoparticles(LHP NPs) are highly promising materials for next-generation displays and solid-state lighting due to their exceptional optical properties. However, their inherent instability presents a significant challenge. Recent advances have demonstrated that optoelectronic devices based on monolayer nanoparticle films exhibit both high luminescence efficiency and long-term stability.Our research demonstrates that mobility limitations and anisotropic alignments in CsPbBr3nanocube monolayer films are key to their stabilization, hindering spontaneous growth through face-to-face fusion and resulting in the formation of connecting necks in a diagonal direction. Introducing laser irradiation confirmed this by significantly accelerating nanocubes growth, increasing mobility, and enhancing local structural ordering, leading to larger and more regularly shaped nanosheets. Fourier transform infrared spectroscopy and energy dispersive spectroscopy line-scan analyses indicated that laser irradiation did not disrupt the ligand structure. Transmission electron microscopy and correlative cathodoluminescence electron microscopy revealed the effects of post-growth and heterogeneous structures, including enhanced luminescence and inhomogeneous intensity in the nanosheets. These findings deepen the understanding of the post-growth mechanism of monolayer nanoparticles and the structure-emission correlation and highlight the unique role of laser irradiation in directing the formation of well-defined and regular nanostructures.展开更多
With advances in organoboron chemistry,boron-centered functional groups,especially alkyl boronic acids,which are widely available,bench stable,easy to prepare,minimally toxic,and structurally diverse,have become incre...With advances in organoboron chemistry,boron-centered functional groups,especially alkyl boronic acids,which are widely available,bench stable,easy to prepare,minimally toxic,and structurally diverse,have become increasingly attractive.However,their utility is limited by their high oxidation potentials.In this study,we overcame this limitation by complexing an inorganic base(K_(3)PO_(4))with alkyl boronic acids to decrease their oxidation potentials.Specifically,we present a powerful method for light-mediated deboronative cross-coupling reactions between alkyl boronic acids and aryl halides to afford products.This method demonstrated good functional group tolerance,and the mild conditions enabled the functionalization of drug molecules.In addition,the method could be extended to three-component carboacylation/carboarylation reactions of olefins to give products with high enantiomeric excess.Moreover,the reactions could be carried out under continuous-flow conditions,which enhanced the scalability,safety,and overall efficiency of the method.展开更多
Objective:To coat a zirconia surface with silica-zirconia using a dip-coating technique and evaluate its effect on resin-zirconia shear bond strength(SBS).Methods:A silica-zirconia suspension was prepared and used to ...Objective:To coat a zirconia surface with silica-zirconia using a dip-coating technique and evaluate its effect on resin-zirconia shear bond strength(SBS).Methods:A silica-zirconia suspension was prepared and used to coat a zirconia surface using a dip-coating technique.One hundred and eighty-nine zirconia disks were divided into three groups according to their different surface treatments(polishing,sandblasting,and silica-zirconia coating).Scanning electron microscopy(SEM),energy dispersive X-ray(EDX),and X-ray diffraction(XRD)were used to analyze the differently treated zirconia surfaces.Different primer treatments(Monobond N,Z-PRIME Plus,and no primer)were also applied to the zirconia surfaces.Subsequently,180 composite resin cylinders(Filtek Z350)were cemented onto the zirconia disks with resin cement(RelyX Ultimate).The SBS was measured after water storage for 24 h or 6 months.The data were analyzed by two-way analysis of variance(ANOVA).Results:SEM and EDX showed that the silica-zirconia coating produced a porous layer with additional Si,and XRD showed that only tetragonal zirconia was on the silica-zirconia-coating surface.Compared with the control group,the resin-zirconia SBSs of the,andblasting group and silica-zirconia-coating group were significantly increased(P<0.05).The silica-zirconia coating followed by the application of Monobond N produced the highest SBS(P<0.05).Water aging significantly reduced the resin-zirconia SBS(P<0.05).Conclusions:Dip-coating with silica-zirconia might be a feasible way to improve resin-zirconia bonding.展开更多
In this paper, some properties of solutions of linear differential equations f^（k）＋A（z）f = 0 and f（k）＋ A（z）f = F（z） are discussed. Our results are a generalization of the original results.
Air-sea water vapor and CO_(2) flux observation experiments were carried out at the Yantai National Satellite Ocean Calibration Platform and the jetty at Monolithic Beach,Juehua Island,using a 100 Hz gas analyzer.The ...Air-sea water vapor and CO_(2) flux observation experiments were carried out at the Yantai National Satellite Ocean Calibration Platform and the jetty at Monolithic Beach,Juehua Island,using a 100 Hz gas analyzer.The observations were corrected by employing wild point rejection,linear detrending,delay correction,coordinate rotation,time matching,and Webb,Pearman,and Leuning(WPL)correction.The results of spectral analysis and a turbulence development adequacy data quality check showed that the overall observation data quality was good.The air-sea water vapor and CO_(2) flux results showed that the observation duration affected both the air-sea flux intensity and direction at different observation frequencies.At shorter observation durations,the air-sea flux values measured at 100 Hz were smaller than the 20 Hz measurements and had opposite directions.In addition,the WPL correction reduced the overall air-sea flux and partially minimized the effect of observation frequency on the air-sea flux intensity.These results showed that high-frequency observations showed more turbulence variations than low-frequency observations.This conclusion could promote an understanding of small-scale turbulence variations.展开更多
The rising prevalence of multidrug-resistant pathogens poses a substantial threat to global healthcare systems,demanding urgent therapeutic interventions.Microorganisms exhibit diverse resistance mechanisms against va...The rising prevalence of multidrug-resistant pathogens poses a substantial threat to global healthcare systems,demanding urgent therapeutic interventions.Microorganisms exhibit diverse resistance mechanisms against various classes of antibiotics,highlighting the urgent need to discover novel antimicrobial agents for combating bacterial infections.Anti-virulence therapy has emerged as a promising therapeutic strategy that neutralizes pathogens by targeting their virulence determinants.The strategies for screening virulence arresting drugs(VADs)in bacteria represent a multifaceted approach that involves elucidating molecular pathogenesis mechanisms of bacterial pathogenicity,identifying evolutionarily conserved virulence factors across different pathogens,and employing integrated approaches combining in silico prediction with experimental validation.Recent technological advancements have established standardized protocols for effective identification and validation of anti-virulence compounds.This review systematically examines contemporary screening methodologies,primarily focusing on quorum-sensing disruption and biofilm suppression strategies,including in silico screening,activity-based screening with bioassays,in vitro and in vivo models.Additionally,we emphasize the imperative for standardized preclinical validation through physiologically relevant animal models,while proposing framework recommendations for developing next-generation VAD screening platforms.This synthesis not only outlines current best practices but also proposes innovative avenues for future antimicrobial discovery research.展开更多
Ecosystems have increasingly been subject to the challenge of heavy drought under global warming. To quantitatively evaluate the impacts of drought on ecosystems, it is necessary to develop a drought index that can se...Ecosystems have increasingly been subject to the challenge of heavy drought under global warming. To quantitatively evaluate the impacts of drought on ecosystems, it is necessary to develop a drought index that can sensitively depict the response of vegetation to drought evolution at a biological time scale. For the ability of direct connection between climate and ecosystem by deficit of evapotranspiration, in the present study, a drought index was defined based on standardized evapotranspiration deficit (SEDI), according to the difference between actual and potential evapotranspiration, to meet the need for highlighting drought impacts on ecological processes. Comparisons with traditional indices show that SEDI can reasonably detect droughts and climatic dry and wet transitions, especially at a monthly time scale, and can also regenerate long-term trends. Moreover, SEDI can more sensitively capture the biological changes of ecosystems in response to the dynamics of drought intensity, compared with the indices of precipitation and temperature. SEDI is more practical than the precipitation and temperature indices to highlight signals of biological effects in climate droughts. Hence, it has potential for use in assessments of climate change and its impact on ecosystems.展开更多
As a ligand-dependent transcription factor,retinoid-associated orphan receptor gt(RORγt)that controls T helper(Th)17 cell differentiation and interleukin(IL)-17 expression plays a critical role in the progression of ...As a ligand-dependent transcription factor,retinoid-associated orphan receptor gt(RORγt)that controls T helper(Th)17 cell differentiation and interleukin(IL)-17 expression plays a critical role in the progression of several inflammatory and autoimmune conditions.An emerging novel approach to the therapy of these diseases thus involves controlling the transcriptional capacity of RORγt to decrease Th17 cell development and IL-17 production.Several RORγt inhibitors including both antagonists and inverse agonists have been discovered to regulate the transcriptional activity of RORγt by binding to orthosteric-or allosteric-binding sites in the ligand-binding domain.Some of small-molecule inhibitors have entered clinical evaluations.Therefore,in current review,the role of RORγt in Th17 regulation and Th17-related inflammatory and autoimmune diseases was highlighted.Notably,the recently developed RORγt inhibitors were summarized,with an emphasis on their optimization from lead compounds,efficacy,toxicity,mechanisms of action,and clinical trials.The limitations of current development in this area were also discussed to facilitate future research.展开更多
Interference with quorum sensing(QS)represents an antivirulence strategy with a significant promise for the treatment of bacterial infections and a new approach to restoring antibiotic tolerance.Over the past two deca...Interference with quorum sensing(QS)represents an antivirulence strategy with a significant promise for the treatment of bacterial infections and a new approach to restoring antibiotic tolerance.Over the past two decades,a novel series of studies have reported that quorum quenching approaches and the discovery of quorum sensing inhibitors(QSIs)have a strong impact on the discovery of anti-infective drugs against various types of bacteria.The discovery of QSI was demonstrated to be an appropriate strategy to expand the anti-infective therapeutic approaches to complement classical antibiotics and antimicrobial agents.For the discovery of QSIs,diverse approaches exist and develop in-step with the scale of screening as well as specific QS systems.This review highlights the latest findings in strategies and methodologies for QSI screening,involving activity-based screening with bioassays,chemical methods to seek bacterial QS pathways for QSI discovery,virtual screening for QSI screening,and other potential tools for interpreting QS signaling,which are innovative routes for future efforts to discover additional QSIs to combat bacterial infections.展开更多
Extracellular polymeric substances(EPS)constitutes crucial elements within bacterial biofilms,facili-tating accelerated antimicrobial resistance and conferring defense against the host's immune cells.Developing pr...Extracellular polymeric substances(EPS)constitutes crucial elements within bacterial biofilms,facili-tating accelerated antimicrobial resistance and conferring defense against the host's immune cells.Developing precise and effective antibiofilm approaches and strategies,tailored to the specific charac-teristics of EPS composition,can offer valuable insights for the creation of novel antimicrobial drugs.This,in turn,holds the potential to mitigate the alarming issue of bacterial drug resistance.Current analysis of EPS compositions relies heavily on colorimetric approaches with a significant bias,which is likely due to the selection of a standard compound and the cross-interference of various EPS compounds.Considering the pivotal role of EPS in biofilm functionality,it is imperative for EPS research to delve deeper into the analysis of intricate compositions,moving beyond the current focus on polymeric materials.This ne-cessitates a shift from heavy reliance on colorimetric analytic methods to more comprehensive and nuanced analytical approaches.In this study,we have provided a comprehensive summary of existing analytical methods utilized in the characterization of EPS compositions.Additionally,novel strategies aimed at targeting EPS to enhance biofilm penetration were explored,with a specific focus on high-lighting the limitations associated with colorimetric methods.Furthermore,we have outlined the challenges faced in identifying additional components of EPS and propose a prospective research plan to address these challenges.This review has the potential to guide future researchers in the search for novel compounds capable of suppressing EPS,thereby inhibiting biofilm formation.This insight opens up a new avenue for exploration within this research domain.展开更多
Glass formation is frequently observed in metallic alloys.Machine learning has been applied to discover new metallic glasses.However,the incomplete understanding of glass formation hinders descriptor selection and mat...Glass formation is frequently observed in metallic alloys.Machine learning has been applied to discover new metallic glasses.However,the incomplete understanding of glass formation hinders descriptor selection and material property representation.Here,we use X-ray diffraction spectra,the essential tool for identifying amorphous structure,as an intermediate link.By representing spectra as images,we train generative models to produce high-fidelity spectra for all alloys in multicomponent alloy systems.Training with spectra from a tiny fraction of the total alloys is sufficient for accurate spectra generation,enabling the identification of compositional regions with a high probability of glass formation.The shift from numerical to image-based representation unlocks the potential of machine learning in the design of glass-forming alloys.Furthermore,our approach is applicable to a wide range of materials and spectroscopic techniques.We anticipate that this strategy will accelerate materials discovery across previously unexplored compositional and processing spaces.展开更多
Tumor cells along with a small proportion of cancer stem cells exist in a stromal microenvironment consisting of vasculature, cancer-associated fibroblasts, immune cells and extracellular components.Recent epidemiolog...Tumor cells along with a small proportion of cancer stem cells exist in a stromal microenvironment consisting of vasculature, cancer-associated fibroblasts, immune cells and extracellular components.Recent epidemiological and clinical studies strongly support that vitamin D supplementation is associated with reduced cancer risk and favorable prognosis. Experimental results suggest that vitamin D not only suppresses cancer cells, but also regulates tumor microenvironment to facilitate tumor repression. In this review, we have outlined the current knowledge on epidemiological studies and clinical trials of vitamin D. Notably, wesummarized and discussed the anticancer action of vitamin D in cancer cells, cancer stem cells and stroma cells in tumor microenvironment, providing a better understanding of the role of vitamin D in cancer. We presently re-propose vitamin D to be a novel and economical anticancer agent.展开更多
Ulcerative colitis(UC)is one of types of inflammatory bowel disease with high recurrence.Recent studies have highlighted that microbial dysbiosis as well as abnormal gut immunity are crucial factors that initiate a se...Ulcerative colitis(UC)is one of types of inflammatory bowel disease with high recurrence.Recent studies have highlighted that microbial dysbiosis as well as abnormal gut immunity are crucial factors that initiate a series of inflammatory responses in the UC.Modulating the gut microbiota-intestinal immunity loop has been suggested as one of key strategies for relieving UC.Many Chinese herbal medicines including some of single herb,herbal formulas and the derived constituents have been reported with protective effect against UC through modulating gut microbiome and intestinal immunity.Some clinical trials have shown promising results.This review thus focused on the current knowledge on using Chinese herbal medicines for treating UC from the mechanism aspects of regulating intestinal homeostasis involving microbiota and gut immunity.The existing clinical trials are also summarized.展开更多
Since the 1960 s,the global land surface wind speed(SWS)has significantly weakened,a phenomenon known as global terrestrial stilling.The latest research found that the stilling reversed around 2010,and since then the ...Since the 1960 s,the global land surface wind speed(SWS)has significantly weakened,a phenomenon known as global terrestrial stilling.The latest research found that the stilling reversed around 2010,and since then the global SWS has been strengthening.However,there is still a lack of systematic quantitative analysis in China.We analyzed the transition and regional differences in the long-term trends of the SWS in China based on observational SWS data from 1971 to 2019.The results showed that annual mean SWS in China underwent a reversal from a continuously weakening trend to a significantly strengthening trend around 2014 and implying that stilling may have ended in 2014.The reversal had obvious regional and seasonal variations.In Northeast China,Western Xinjiang as well as on the Tibetan Plateau,the years with both annual and seasonal mean SWS changing from weakening to strengthening were around 2013/2014,1993/1994,and 2000.However,in the west of North China,SWS showed an obviously strengthening trend only in autumn and winter after 2007;while only autumn mean SWS showed a strengthening trend after 2012 in South China.It should be noted that stilling is ongoing in the eastern and southern coastal areas,North China and Eastern Xinjiang.展开更多
The microstructure of polymer-derived ceramics(PDCs)was closely related to processing.This study demonstrated that SiCN matrix prepared by polymer infiltration and pyrolysis(PIP)at 900℃ inside a Si_(3)N_(4) whisker(S...The microstructure of polymer-derived ceramics(PDCs)was closely related to processing.This study demonstrated that SiCN matrix prepared by polymer infiltration and pyrolysis(PIP)at 900℃ inside a Si_(3)N_(4) whisker(Si_(3)N_(4w))preform with submicro-sized pores differed from its powder-consolidated analogue in both the content and structure of free carbon.Chemical analysis showed that PIP process had a higher free carbon yield.Raman spectroscopy and transmission electron microscopy(TEM)observation discovered a higher graphitization degree of free carbon and the existence of nanocrystalline graphite in SiCN matrix.Dielectric properties of Si_(3)N_(4w)/SiCN composites were greatly enhanced when volume fraction of SiCN matrix reached 24.5%due to dielectric percolation caused by highly-lossy free carbon.Reconsolidation of hydrocarbon released during pyrolysis by gas-state carbonization in Si_(3)N_(4) whisker preform was supposed to account for the high yield and graphitization degree of free carbon in PIP process.展开更多
Oxidation of metallic glasses has been shown to be different from crystalline alloys due to the disordered atomic structures and far-from-equilibrium state,and quick characterization is required to reveal their early ...Oxidation of metallic glasses has been shown to be different from crystalline alloys due to the disordered atomic structures and far-from-equilibrium state,and quick characterization is required to reveal their early stage oxidation.In this study,we investigated the oxidation behavior of a Zr_(46)Cu_(46)Al_(7)Gd_(1)bulk metallic glass by measuring the changes of optical constants via spectroscopic ellipsometry.Characterizations with X-ray diffraction,scanning electron microscopy,and thermogravimetric analyzer confirmed that the changes of pseudo-optical constants reflected not only the onset temperature at which the alloys underwent obvious oxidation,but also the subtle oxidation which was tedious to characterize.Our study suggests a more efficient and accurate approach to understand the oxidation of metallic glasses with temperature,time and compositions.展开更多
基金National Key Research and Development Program of China(2023YFA1507602)National Natural Science Foundation of China (22171010, 62174011)。
文摘Lead-halide perovskite nanoparticles(LHP NPs) are highly promising materials for next-generation displays and solid-state lighting due to their exceptional optical properties. However, their inherent instability presents a significant challenge. Recent advances have demonstrated that optoelectronic devices based on monolayer nanoparticle films exhibit both high luminescence efficiency and long-term stability.Our research demonstrates that mobility limitations and anisotropic alignments in CsPbBr3nanocube monolayer films are key to their stabilization, hindering spontaneous growth through face-to-face fusion and resulting in the formation of connecting necks in a diagonal direction. Introducing laser irradiation confirmed this by significantly accelerating nanocubes growth, increasing mobility, and enhancing local structural ordering, leading to larger and more regularly shaped nanosheets. Fourier transform infrared spectroscopy and energy dispersive spectroscopy line-scan analyses indicated that laser irradiation did not disrupt the ligand structure. Transmission electron microscopy and correlative cathodoluminescence electron microscopy revealed the effects of post-growth and heterogeneous structures, including enhanced luminescence and inhomogeneous intensity in the nanosheets. These findings deepen the understanding of the post-growth mechanism of monolayer nanoparticles and the structure-emission correlation and highlight the unique role of laser irradiation in directing the formation of well-defined and regular nanostructures.
基金the National Natural Science Foundation of China(No.22271166)the Frontiers Science Center for New Organic Matter,Nankai University(No.63181206),for generous financial support。
文摘With advances in organoboron chemistry,boron-centered functional groups,especially alkyl boronic acids,which are widely available,bench stable,easy to prepare,minimally toxic,and structurally diverse,have become increasingly attractive.However,their utility is limited by their high oxidation potentials.In this study,we overcame this limitation by complexing an inorganic base(K_(3)PO_(4))with alkyl boronic acids to decrease their oxidation potentials.Specifically,we present a powerful method for light-mediated deboronative cross-coupling reactions between alkyl boronic acids and aryl halides to afford products.This method demonstrated good functional group tolerance,and the mild conditions enabled the functionalization of drug molecules.In addition,the method could be extended to three-component carboacylation/carboarylation reactions of olefins to give products with high enantiomeric excess.Moreover,the reactions could be carried out under continuous-flow conditions,which enhanced the scalability,safety,and overall efficiency of the method.
基金supported by the National Natural Science Foundation of China(No.81771120)the Zhejiang Provincial Natural Science Foundation of China(Nos.LGF20H140009and LQ18H140001)。
文摘Objective:To coat a zirconia surface with silica-zirconia using a dip-coating technique and evaluate its effect on resin-zirconia shear bond strength(SBS).Methods:A silica-zirconia suspension was prepared and used to coat a zirconia surface using a dip-coating technique.One hundred and eighty-nine zirconia disks were divided into three groups according to their different surface treatments(polishing,sandblasting,and silica-zirconia coating).Scanning electron microscopy(SEM),energy dispersive X-ray(EDX),and X-ray diffraction(XRD)were used to analyze the differently treated zirconia surfaces.Different primer treatments(Monobond N,Z-PRIME Plus,and no primer)were also applied to the zirconia surfaces.Subsequently,180 composite resin cylinders(Filtek Z350)were cemented onto the zirconia disks with resin cement(RelyX Ultimate).The SBS was measured after water storage for 24 h or 6 months.The data were analyzed by two-way analysis of variance(ANOVA).Results:SEM and EDX showed that the silica-zirconia coating produced a porous layer with additional Si,and XRD showed that only tetragonal zirconia was on the silica-zirconia-coating surface.Compared with the control group,the resin-zirconia SBSs of the,andblasting group and silica-zirconia-coating group were significantly increased(P<0.05).The silica-zirconia coating followed by the application of Monobond N produced the highest SBS(P<0.05).Water aging significantly reduced the resin-zirconia SBS(P<0.05).Conclusions:Dip-coating with silica-zirconia might be a feasible way to improve resin-zirconia bonding.
基金Supported by the National Natural Science Foundation of China(Grant Nos.1130123211171119)+1 种基金the Youth Science Foundation of Education Bureau of Jiangxi Province(Grant No.GJJ12207)the Natural Science Foundation of Jiangxi Province(Grant No.20132BAB211009)
文摘In this paper, some properties of solutions of linear differential equations f^（k）＋A（z）f = 0 and f（k）＋ A（z）f = F（z） are discussed. Our results are a generalization of the original results.
基金The National Key Research and Development Program of China under contract Nos 2022YFC3104203 and 2018YFC0213103the Science Foundation of Donghai Laboratory under contract No.DH-2022KF01019+1 种基金the National Natural Science Foundation under contract No.419061522023 Shanghai Education Science Research Project under contract No.C2023120.
文摘Air-sea water vapor and CO_(2) flux observation experiments were carried out at the Yantai National Satellite Ocean Calibration Platform and the jetty at Monolithic Beach,Juehua Island,using a 100 Hz gas analyzer.The observations were corrected by employing wild point rejection,linear detrending,delay correction,coordinate rotation,time matching,and Webb,Pearman,and Leuning(WPL)correction.The results of spectral analysis and a turbulence development adequacy data quality check showed that the overall observation data quality was good.The air-sea water vapor and CO_(2) flux results showed that the observation duration affected both the air-sea flux intensity and direction at different observation frequencies.At shorter observation durations,the air-sea flux values measured at 100 Hz were smaller than the 20 Hz measurements and had opposite directions.In addition,the WPL correction reduced the overall air-sea flux and partially minimized the effect of observation frequency on the air-sea flux intensity.These results showed that high-frequency observations showed more turbulence variations than low-frequency observations.This conclusion could promote an understanding of small-scale turbulence variations.
基金supported by the National Natural Science Foundation of China(Grant No:82474158)the Natural Science Foundation of Sichuan Province,China(Grant No.:2024NSFSC0708).
文摘The rising prevalence of multidrug-resistant pathogens poses a substantial threat to global healthcare systems,demanding urgent therapeutic interventions.Microorganisms exhibit diverse resistance mechanisms against various classes of antibiotics,highlighting the urgent need to discover novel antimicrobial agents for combating bacterial infections.Anti-virulence therapy has emerged as a promising therapeutic strategy that neutralizes pathogens by targeting their virulence determinants.The strategies for screening virulence arresting drugs(VADs)in bacteria represent a multifaceted approach that involves elucidating molecular pathogenesis mechanisms of bacterial pathogenicity,identifying evolutionarily conserved virulence factors across different pathogens,and employing integrated approaches combining in silico prediction with experimental validation.Recent technological advancements have established standardized protocols for effective identification and validation of anti-virulence compounds.This review systematically examines contemporary screening methodologies,primarily focusing on quorum-sensing disruption and biofilm suppression strategies,including in silico screening,activity-based screening with bioassays,in vitro and in vivo models.Additionally,we emphasize the imperative for standardized preclinical validation through physiologically relevant animal models,while proposing framework recommendations for developing next-generation VAD screening platforms.This synthesis not only outlines current best practices but also proposes innovative avenues for future antimicrobial discovery research.
基金sponsored by the National Key R&D Program of China (Grant No. 2018YFA0606002)the National Natural Science Foundation of China (Grant Nos. 41575087 and 41875082)the UK–China Research & Innovation Partnership Fund through the Met Office Climate Science for Service Partnership (CSSP) China as part of the Newton Fund
文摘Ecosystems have increasingly been subject to the challenge of heavy drought under global warming. To quantitatively evaluate the impacts of drought on ecosystems, it is necessary to develop a drought index that can sensitively depict the response of vegetation to drought evolution at a biological time scale. For the ability of direct connection between climate and ecosystem by deficit of evapotranspiration, in the present study, a drought index was defined based on standardized evapotranspiration deficit (SEDI), according to the difference between actual and potential evapotranspiration, to meet the need for highlighting drought impacts on ecological processes. Comparisons with traditional indices show that SEDI can reasonably detect droughts and climatic dry and wet transitions, especially at a monthly time scale, and can also regenerate long-term trends. Moreover, SEDI can more sensitively capture the biological changes of ecosystems in response to the dynamics of drought intensity, compared with the indices of precipitation and temperature. SEDI is more practical than the precipitation and temperature indices to highlight signals of biological effects in climate droughts. Hence, it has potential for use in assessments of climate change and its impact on ecosystems.
基金supported by the grants from the Sichuan Science and Technology Program,China(Grant Nos.:2023NSFSC0614 and 2022YFS0624)Southwest Medical University Science and Technology Program,China(Grant No.:2021ZKZD017)+2 种基金the Luzhou Science and Technology Program,China(Grant Nos.:2022-YJY-127,2022YFS0624-B1,2022YFS0624-C1,and 2022YFS0624-B3)the Open Research Project Program funded by the Science and Technology Development Fund(Grant No.:SKL-QRCM(UM)-2020-2022)the State Key Laboratory of Quality Research in Chinese Medicine(University of Macao,Macao,China)(Grant No.:SKL-QRCMOP21006).
文摘As a ligand-dependent transcription factor,retinoid-associated orphan receptor gt(RORγt)that controls T helper(Th)17 cell differentiation and interleukin(IL)-17 expression plays a critical role in the progression of several inflammatory and autoimmune conditions.An emerging novel approach to the therapy of these diseases thus involves controlling the transcriptional capacity of RORγt to decrease Th17 cell development and IL-17 production.Several RORγt inhibitors including both antagonists and inverse agonists have been discovered to regulate the transcriptional activity of RORγt by binding to orthosteric-or allosteric-binding sites in the ligand-binding domain.Some of small-molecule inhibitors have entered clinical evaluations.Therefore,in current review,the role of RORγt in Th17 regulation and Th17-related inflammatory and autoimmune diseases was highlighted.Notably,the recently developed RORγt inhibitors were summarized,with an emphasis on their optimization from lead compounds,efficacy,toxicity,mechanisms of action,and clinical trials.The limitations of current development in this area were also discussed to facilitate future research.
基金funded by the National Natural Science Foundation of China (Grant No.: 81803812)
文摘Interference with quorum sensing(QS)represents an antivirulence strategy with a significant promise for the treatment of bacterial infections and a new approach to restoring antibiotic tolerance.Over the past two decades,a novel series of studies have reported that quorum quenching approaches and the discovery of quorum sensing inhibitors(QSIs)have a strong impact on the discovery of anti-infective drugs against various types of bacteria.The discovery of QSI was demonstrated to be an appropriate strategy to expand the anti-infective therapeutic approaches to complement classical antibiotics and antimicrobial agents.For the discovery of QSIs,diverse approaches exist and develop in-step with the scale of screening as well as specific QS systems.This review highlights the latest findings in strategies and methodologies for QSI screening,involving activity-based screening with bioassays,chemical methods to seek bacterial QS pathways for QSI discovery,virtual screening for QSI screening,and other potential tools for interpreting QS signaling,which are innovative routes for future efforts to discover additional QSIs to combat bacterial infections.
基金funded by the National Natural Science Foundation of China(Grant Nos.:81803812,81803237).
文摘Extracellular polymeric substances(EPS)constitutes crucial elements within bacterial biofilms,facili-tating accelerated antimicrobial resistance and conferring defense against the host's immune cells.Developing precise and effective antibiofilm approaches and strategies,tailored to the specific charac-teristics of EPS composition,can offer valuable insights for the creation of novel antimicrobial drugs.This,in turn,holds the potential to mitigate the alarming issue of bacterial drug resistance.Current analysis of EPS compositions relies heavily on colorimetric approaches with a significant bias,which is likely due to the selection of a standard compound and the cross-interference of various EPS compounds.Considering the pivotal role of EPS in biofilm functionality,it is imperative for EPS research to delve deeper into the analysis of intricate compositions,moving beyond the current focus on polymeric materials.This ne-cessitates a shift from heavy reliance on colorimetric analytic methods to more comprehensive and nuanced analytical approaches.In this study,we have provided a comprehensive summary of existing analytical methods utilized in the characterization of EPS compositions.Additionally,novel strategies aimed at targeting EPS to enhance biofilm penetration were explored,with a specific focus on high-lighting the limitations associated with colorimetric methods.Furthermore,we have outlined the challenges faced in identifying additional components of EPS and propose a prospective research plan to address these challenges.This review has the potential to guide future researchers in the search for novel compounds capable of suppressing EPS,thereby inhibiting biofilm formation.This insight opens up a new avenue for exploration within this research domain.
基金supported by the National Natural Science Foundation of China(grant nos.52331007,52192602,T2222028,52471189).The AI-driven experiments,simulations and model trainingwere performed on the robotic AI-Scientist platform of Chinese Academy of Sciences.
文摘Glass formation is frequently observed in metallic alloys.Machine learning has been applied to discover new metallic glasses.However,the incomplete understanding of glass formation hinders descriptor selection and material property representation.Here,we use X-ray diffraction spectra,the essential tool for identifying amorphous structure,as an intermediate link.By representing spectra as images,we train generative models to produce high-fidelity spectra for all alloys in multicomponent alloy systems.Training with spectra from a tiny fraction of the total alloys is sufficient for accurate spectra generation,enabling the identification of compositional regions with a high probability of glass formation.The shift from numerical to image-based representation unlocks the potential of machine learning in the design of glass-forming alloys.Furthermore,our approach is applicable to a wide range of materials and spectroscopic techniques.We anticipate that this strategy will accelerate materials discovery across previously unexplored compositional and processing spaces.
基金supported by the National Natural Science Foundation of China(Nos.81770562,81602166 and 81703807)grants from the Science and Technology Planning Project of Luzhou,Sichuan Province,China(Nos.2016LZXNYD-Z04 and 2017LZXNYD-J02)
文摘Tumor cells along with a small proportion of cancer stem cells exist in a stromal microenvironment consisting of vasculature, cancer-associated fibroblasts, immune cells and extracellular components.Recent epidemiological and clinical studies strongly support that vitamin D supplementation is associated with reduced cancer risk and favorable prognosis. Experimental results suggest that vitamin D not only suppresses cancer cells, but also regulates tumor microenvironment to facilitate tumor repression. In this review, we have outlined the current knowledge on epidemiological studies and clinical trials of vitamin D. Notably, wesummarized and discussed the anticancer action of vitamin D in cancer cells, cancer stem cells and stroma cells in tumor microenvironment, providing a better understanding of the role of vitamin D in cancer. We presently re-propose vitamin D to be a novel and economical anticancer agent.
基金supported by the grants from the Sichuan Science and Technology Program,China(No.2023NSFSC0614,2022YFS0624)grant from Science and Technology Program of Luzhou,China(No.21CGZHPT0001,2022-YJY-127)+1 种基金grant from Southwest Medical University,China(No.2021ZKZD017)grant from The Open Research Project Program of the State Key Laboratory of Quality Research in Chinese Medicine(University of Macao),China(SKL-QRCM-OP21006).
文摘Ulcerative colitis(UC)is one of types of inflammatory bowel disease with high recurrence.Recent studies have highlighted that microbial dysbiosis as well as abnormal gut immunity are crucial factors that initiate a series of inflammatory responses in the UC.Modulating the gut microbiota-intestinal immunity loop has been suggested as one of key strategies for relieving UC.Many Chinese herbal medicines including some of single herb,herbal formulas and the derived constituents have been reported with protective effect against UC through modulating gut microbiome and intestinal immunity.Some clinical trials have shown promising results.This review thus focused on the current knowledge on using Chinese herbal medicines for treating UC from the mechanism aspects of regulating intestinal homeostasis involving microbiota and gut immunity.The existing clinical trials are also summarized.
基金supported by the National Key R&D Program of China(Grant No.2016YFA0600404)the National Natural Science Foundation of China(Grant Nos.41705073,41530532,41506040)the Jiangsu Collaborative Innovation Center for Climate Change。
文摘Since the 1960 s,the global land surface wind speed(SWS)has significantly weakened,a phenomenon known as global terrestrial stilling.The latest research found that the stilling reversed around 2010,and since then the global SWS has been strengthening.However,there is still a lack of systematic quantitative analysis in China.We analyzed the transition and regional differences in the long-term trends of the SWS in China based on observational SWS data from 1971 to 2019.The results showed that annual mean SWS in China underwent a reversal from a continuously weakening trend to a significantly strengthening trend around 2014 and implying that stilling may have ended in 2014.The reversal had obvious regional and seasonal variations.In Northeast China,Western Xinjiang as well as on the Tibetan Plateau,the years with both annual and seasonal mean SWS changing from weakening to strengthening were around 2013/2014,1993/1994,and 2000.However,in the west of North China,SWS showed an obviously strengthening trend only in autumn and winter after 2007;while only autumn mean SWS showed a strengthening trend after 2012 in South China.It should be noted that stilling is ongoing in the eastern and southern coastal areas,North China and Eastern Xinjiang.
基金supported by the National Natural Science Foundation of China(Grant Nos.51632007,51872229,and 52072304)National Science and Technology Major Project(Grant No.2017-VI-0007-0077).
文摘The microstructure of polymer-derived ceramics(PDCs)was closely related to processing.This study demonstrated that SiCN matrix prepared by polymer infiltration and pyrolysis(PIP)at 900℃ inside a Si_(3)N_(4) whisker(Si_(3)N_(4w))preform with submicro-sized pores differed from its powder-consolidated analogue in both the content and structure of free carbon.Chemical analysis showed that PIP process had a higher free carbon yield.Raman spectroscopy and transmission electron microscopy(TEM)observation discovered a higher graphitization degree of free carbon and the existence of nanocrystalline graphite in SiCN matrix.Dielectric properties of Si_(3)N_(4w)/SiCN composites were greatly enhanced when volume fraction of SiCN matrix reached 24.5%due to dielectric percolation caused by highly-lossy free carbon.Reconsolidation of hydrocarbon released during pyrolysis by gas-state carbonization in Si_(3)N_(4) whisker preform was supposed to account for the high yield and graphitization degree of free carbon in PIP process.
基金the National Key Research and Development Program of China(2018YFA0703600 and2017YFB0701900)the National Natural Science Foundation of China(51825104,51801095,11790291 and 61888102)+1 种基金CAS projects(XDB30000000)the Key Basic and Applied Research Program of Guangdong Province of China(2019B030302010)。
文摘Oxidation of metallic glasses has been shown to be different from crystalline alloys due to the disordered atomic structures and far-from-equilibrium state,and quick characterization is required to reveal their early stage oxidation.In this study,we investigated the oxidation behavior of a Zr_(46)Cu_(46)Al_(7)Gd_(1)bulk metallic glass by measuring the changes of optical constants via spectroscopic ellipsometry.Characterizations with X-ray diffraction,scanning electron microscopy,and thermogravimetric analyzer confirmed that the changes of pseudo-optical constants reflected not only the onset temperature at which the alloys underwent obvious oxidation,but also the subtle oxidation which was tedious to characterize.Our study suggests a more efficient and accurate approach to understand the oxidation of metallic glasses with temperature,time and compositions.
