In recent years,the depletion risk of fossil fuels has driven increasing interest in renewable energy.Among various technologies,proton exchange membrane fuel cells(PEMFCs)stand out due to their fast startup and high ...In recent years,the depletion risk of fossil fuels has driven increasing interest in renewable energy.Among various technologies,proton exchange membrane fuel cells(PEMFCs)stand out due to their fast startup and high power density.However,the commonly used Nafion membranes suffer from reduced proton conductivity under low humidity and high temperatures,limiting their practical application.Polyoxometalates(POMs),with their excellent proton conductivity and thermal stability,have emerged as promising alternatives.Yet,their high water solubility raises safety concerns,and their water-dependent conduction mechanisms and structure–function relationships remain insufficiently understood.These issues hinder the practical development of POM-based proton conductors.This paper presents a comprehensive review of the key properties and proton conduction mechanisms of POMs,with a particular focus on POM crystals and their composites exhibiting high proton conductivity.Representative studies are analyzed to elucidate design strategies,structure–function relationships,and recent research progress over the past five years.Finally,perspectives and recommendations are proposed to inform future research directions and promote practical applications in the field of proton-conducting materials.展开更多
AIM：To determine the Bruch＇s membrane opening-minimum rim width（BMO-MRW） tipping point where corresponding visual field（VF） damages become detectable.METHODS：A total of 85 normal subjects and 83 glaucoma patie...AIM：To determine the Bruch＇s membrane opening-minimum rim width（BMO-MRW） tipping point where corresponding visual field（VF） damages become detectable.METHODS：A total of 85 normal subjects and 83 glaucoma patients（one eye per participant） were recruited for the study.All of the patients had VF examinations and spectral-domain optical coherence tomography to measure the BMO-MRW.Total deviation values for 52 VF points were allocated to the corresponding sector according to the Garway-Heath distribution map.To evaluate the relationship between VF loss and BMOMRW measurements,a ＂broken-stick＂ statistical model was used.The tipping point where the VF values started to sharply decrease as a function of BMO-MRW measurements was estimated and the slopes above and below this tipping point were compared.RESULTS：A 25.9% global BMO-MRW loss from normative value was required for the VF loss to be detectable.Sectorally,substantial BMO-MRW thinning in inferotemporal sector（33.1%） and relatively less BMO-MRW thinning in the superotemporal sector（8.9%） were necessary for the detection of the VF loss.Beyond the tipping point,the slopes were close to zero throughout all of the sectors and the VF loss was unrelated to the BMO-MRW loss.The VF loss was related to the BMO-MRW loss below the tipping point.The difference between the two slopes was statistically significant（P≤0.002）.CONCLUSION：Substantial BMO-MRW loss appears to be necessary for VF loss to be detectable in patients with open angle glaucoma with standard achromatic perimetry.展开更多
To alleviate the global warming by removing excess CO_(2) and converting them into value-added chemicals,(photo)electrochemical reduction has been recognized as a promising strategy.As the CO_(2) reduction reaction(CO...To alleviate the global warming by removing excess CO_(2) and converting them into value-added chemicals,(photo)electrochemical reduction has been recognized as a promising strategy.As the CO_(2) reduction reaction(CO_(2) RR) is involved with multiple electrons and multiple products,plus the complexity of the surface chemical environment of the catalyst,it is extremely challenging to establish the structure/function relationship.Atomically precise metal nanoclusters(NCs),with crystallographically resolved structure,molecule-like characters and strong quantum confinement effects,have been emerging as a new type of catalyst for CO_(2) RR,and more importantly,they can provide an ideal platform to unravel the comprehensive mechanistic insights and establish the structure/function relationship eventually.In this review,the recent advances regarding employing molecular metal NCs with well-defined structure including Au NCs,Au-based alloy NCs,Ag NCs,Cu NCs for CO_(2) RR and relevant mechanistic studies are discussed,and the opportunities and challenges are proposed at the end for paving the development of CO_(2) RR by using atomically precise metal NCs.展开更多
The mutation sites of the four mutants F35Y, P40V, V45E and V45Y of cytochrome b 5 are located at the edge of the heme binding pocket. The solvent accessible areas of the “pocket interior” of the four mutants ...The mutation sites of the four mutants F35Y, P40V, V45E and V45Y of cytochrome b 5 are located at the edge of the heme binding pocket. The solvent accessible areas of the “pocket interior” of the four mutants and the wild type cytochrome b 5 have been calculated based on their crystal structures at high resolution. The change in the hydrophobicity of the heme binding pocket resulting from the mutation can be quantitatively described using the difference of the solvent accessible area of the “pocket interior” of each mutant from that of the wild type cytochrome b 5. The influences of the hydrophobicity of the heme binding pocket on the protein stability and redox potential are discussed.展开更多
Soil fertility is one of the key determinants of agricultural productivity.Soil food webs play an important role in driving soil nutrient cycling and plant health.However,it is poorly known how the soil food web compo...Soil fertility is one of the key determinants of agricultural productivity.Soil food webs play an important role in driving soil nutrient cycling and plant health.However,it is poorly known how the soil food web composition and complexity affect plant growth and soil fertility.In this study,soil microorganisms and nematodes isolated from two soil types(i.e.,calcareous soil and red soil)and two land use types(i.e.,corn-soybean cultivation and natural grass-shrubland)were used to sequentially establish four soil microfood webs(FW1,FW2,FW3,and FW4)with increasing levels of community complexity based on food web complexity.The four micro-food webs were inoculated to sterilized soils which were then planted with soybeans for three months in a pot experiment under ambient environment.The sterilized soil without food web inoculation was employed as control(C)and unsterilized soil with its original food web was also regarded as a treatment(US)in the experiment.The effects of soil micro-food web complexity on soil nutrient and soybean growth were explored.The results showed that soil total nitrogen(TN)and phosphorus(TP),soil microbial biomasses,and plant nitrogen and phosphorus were generally higher in the four food web inoculation treatments than in the control or unsterilized soil.Surprisingly,the original soil food web treatment(i.e.,unsterilized soil)had lower soil or soybean nutrient than the no food web treatment(i.e.,sterilized soil).In addition,the complexity of inoculated food webs was positively correlated with soil TN,TP,and total potassium(TK).These results suggest that soil micro-food web complexity is an important driver of soil fertility and affects crop growth.Particularly,complex soil micro-food web maintains higher soil fertility and crop growth.This study provides solid evidence of the roles of soil food web in controlling ecosystem services;and the findings could provide a better understanding of the soil food web structure and soil fertility relationships.展开更多
Super-resolution optical imaging overcomes the diffraction limit in light microscopy to enable the visualization of previously invisible molecular details within a sample.The realization of super-resolution imaging ba...Super-resolution optical imaging overcomes the diffraction limit in light microscopy to enable the visualization of previously invisible molecular details within a sample.The realization of super-resolution imaging based on stimulated Raman scattering(SRS)microscopy represents a recent area of fruitful development that has been used to visualize cellular structures in three dimensions,with multiple spectroscopic colors at the nanometer scale.Several fundamental approaches to achieving super-resolution SRS imaging have been reported,including optical engineering strategies,expansion microscopy,deconvolution image analysis,and photoswitchable SRS reporters as methods to break the diffraction limit.These approaches have enabled the visualization of biological structures,cellular interactions,and dynamics with unprecedented detail.In this Perspective,an overview of the current strategies and capabilities for achieving super-resolution SRS imaging will be highlighted together with an outlook on potential directions of this rapidly evolving field.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22203027 and U22A20107)the Henan Province Science and Technology Attack Plan Project(No.242102230020)+6 种基金the Students Innovative Pilot Plan of Henan University(Nos.202510475004 and XJ2025182)“Grassland Talents”of Inner Mongolia Autonomous Region,Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(No.NJYT23030)Technology Breakthrough Engineering Hydrogen Energy Field“Unveiling and Leading”Project(No.2024KJTW0018)“Steed plan High level Talents”of Inner Mongolia University,Carbon neutralization research project(No.STZX202218)Inner Mongolia Autonomous Region Natural Science Foundation(No.2023MS02002)Guangdong Provincial Key Laboratory of Materials and Technologies for Energy Conversion(No.MATEC2024KF011)National Key R&D Program of China(No.2022YFA1205201).
文摘In recent years,the depletion risk of fossil fuels has driven increasing interest in renewable energy.Among various technologies,proton exchange membrane fuel cells(PEMFCs)stand out due to their fast startup and high power density.However,the commonly used Nafion membranes suffer from reduced proton conductivity under low humidity and high temperatures,limiting their practical application.Polyoxometalates(POMs),with their excellent proton conductivity and thermal stability,have emerged as promising alternatives.Yet,their high water solubility raises safety concerns,and their water-dependent conduction mechanisms and structure–function relationships remain insufficiently understood.These issues hinder the practical development of POM-based proton conductors.This paper presents a comprehensive review of the key properties and proton conduction mechanisms of POMs,with a particular focus on POM crystals and their composites exhibiting high proton conductivity.Representative studies are analyzed to elucidate design strategies,structure–function relationships,and recent research progress over the past five years.Finally,perspectives and recommendations are proposed to inform future research directions and promote practical applications in the field of proton-conducting materials.
文摘AIM：To determine the Bruch＇s membrane opening-minimum rim width（BMO-MRW） tipping point where corresponding visual field（VF） damages become detectable.METHODS：A total of 85 normal subjects and 83 glaucoma patients（one eye per participant） were recruited for the study.All of the patients had VF examinations and spectral-domain optical coherence tomography to measure the BMO-MRW.Total deviation values for 52 VF points were allocated to the corresponding sector according to the Garway-Heath distribution map.To evaluate the relationship between VF loss and BMOMRW measurements,a ＂broken-stick＂ statistical model was used.The tipping point where the VF values started to sharply decrease as a function of BMO-MRW measurements was estimated and the slopes above and below this tipping point were compared.RESULTS：A 25.9% global BMO-MRW loss from normative value was required for the VF loss to be detectable.Sectorally,substantial BMO-MRW thinning in inferotemporal sector（33.1%） and relatively less BMO-MRW thinning in the superotemporal sector（8.9%） were necessary for the detection of the VF loss.Beyond the tipping point,the slopes were close to zero throughout all of the sectors and the VF loss was unrelated to the BMO-MRW loss.The VF loss was related to the BMO-MRW loss below the tipping point.The difference between the two slopes was statistically significant（P≤0.002）.CONCLUSION：Substantial BMO-MRW loss appears to be necessary for VF loss to be detectable in patients with open angle glaucoma with standard achromatic perimetry.
基金the grant from the National Natural Science Foundation of China(No.21805170)financial support from Guangdong Natural Science Funds for Distinguished Young Scholars(No.2015A030306006)+1 种基金Guangzhou Science and Technology Plan Projects(No.201804010323)the fundamental funds for central universities(SCUT No.2018ZD022)。
文摘To alleviate the global warming by removing excess CO_(2) and converting them into value-added chemicals,(photo)electrochemical reduction has been recognized as a promising strategy.As the CO_(2) reduction reaction(CO_(2) RR) is involved with multiple electrons and multiple products,plus the complexity of the surface chemical environment of the catalyst,it is extremely challenging to establish the structure/function relationship.Atomically precise metal nanoclusters(NCs),with crystallographically resolved structure,molecule-like characters and strong quantum confinement effects,have been emerging as a new type of catalyst for CO_(2) RR,and more importantly,they can provide an ideal platform to unravel the comprehensive mechanistic insights and establish the structure/function relationship eventually.In this review,the recent advances regarding employing molecular metal NCs with well-defined structure including Au NCs,Au-based alloy NCs,Ag NCs,Cu NCs for CO_(2) RR and relevant mechanistic studies are discussed,and the opportunities and challenges are proposed at the end for paving the development of CO_(2) RR by using atomically precise metal NCs.
文摘The mutation sites of the four mutants F35Y, P40V, V45E and V45Y of cytochrome b 5 are located at the edge of the heme binding pocket. The solvent accessible areas of the “pocket interior” of the four mutants and the wild type cytochrome b 5 have been calculated based on their crystal structures at high resolution. The change in the hydrophobicity of the heme binding pocket resulting from the mutation can be quantitatively described using the difference of the solvent accessible area of the “pocket interior” of each mutant from that of the wild type cytochrome b 5. The influences of the hydrophobicity of the heme binding pocket on the protein stability and redox potential are discussed.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFF1300704)the National Natural Science Foundations of China(Grant Nos.U21A20189,42377284,and 42207339)+2 种基金the Natural Science Foundation of Hunan Province(Grant No.2023JJ41046)the Science and Technology Innovation Program of Hunan Province(Grant No.2023RC1076)the Guangxi Bagui Young Scholars Special Funding given to Jie Zhao.
文摘Soil fertility is one of the key determinants of agricultural productivity.Soil food webs play an important role in driving soil nutrient cycling and plant health.However,it is poorly known how the soil food web composition and complexity affect plant growth and soil fertility.In this study,soil microorganisms and nematodes isolated from two soil types(i.e.,calcareous soil and red soil)and two land use types(i.e.,corn-soybean cultivation and natural grass-shrubland)were used to sequentially establish four soil microfood webs(FW1,FW2,FW3,and FW4)with increasing levels of community complexity based on food web complexity.The four micro-food webs were inoculated to sterilized soils which were then planted with soybeans for three months in a pot experiment under ambient environment.The sterilized soil without food web inoculation was employed as control(C)and unsterilized soil with its original food web was also regarded as a treatment(US)in the experiment.The effects of soil micro-food web complexity on soil nutrient and soybean growth were explored.The results showed that soil total nitrogen(TN)and phosphorus(TP),soil microbial biomasses,and plant nitrogen and phosphorus were generally higher in the four food web inoculation treatments than in the control or unsterilized soil.Surprisingly,the original soil food web treatment(i.e.,unsterilized soil)had lower soil or soybean nutrient than the no food web treatment(i.e.,sterilized soil).In addition,the complexity of inoculated food webs was positively correlated with soil TN,TP,and total potassium(TK).These results suggest that soil micro-food web complexity is an important driver of soil fertility and affects crop growth.Particularly,complex soil micro-food web maintains higher soil fertility and crop growth.This study provides solid evidence of the roles of soil food web in controlling ecosystem services;and the findings could provide a better understanding of the soil food web structure and soil fertility relationships.
基金University of Strathclyde and the EPSRC(EP/N010914/1)for financial support.
文摘Super-resolution optical imaging overcomes the diffraction limit in light microscopy to enable the visualization of previously invisible molecular details within a sample.The realization of super-resolution imaging based on stimulated Raman scattering(SRS)microscopy represents a recent area of fruitful development that has been used to visualize cellular structures in three dimensions,with multiple spectroscopic colors at the nanometer scale.Several fundamental approaches to achieving super-resolution SRS imaging have been reported,including optical engineering strategies,expansion microscopy,deconvolution image analysis,and photoswitchable SRS reporters as methods to break the diffraction limit.These approaches have enabled the visualization of biological structures,cellular interactions,and dynamics with unprecedented detail.In this Perspective,an overview of the current strategies and capabilities for achieving super-resolution SRS imaging will be highlighted together with an outlook on potential directions of this rapidly evolving field.
