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Historical Changes and Multi-scenario Prediction of Land Use and Terrestrial Ecosystem Carbon Storage in China

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Chinese geographical science 2024年第3期34卷 487-503页

作者： AN Yue TAN Xuelan REN Hui LI Yinqi ZHOU Zhou College of Resources Hunan Agricultural UniversityChangsha 410128China school of geographic science Hunan Normal UniversityChangsha 410081China

Terrestrial carbon storage(CS)plays a crucial role in achieving carbon balance and mitigating global climate *** study employs the Shared Socioeconomic Pathways and Representative Concentration Pathways(SSPs-RCPs)published by the Intergovernmental Panel on Climate Change(IPCC)and incorporates the Policy Control Scenario(PCS)regulated by China’s land management *** Future Land Use Simulation(FLUS)model is employed to generate a 1 km resolution land use/cover change(LUCC)dataset for China in 2030 and *** on the carbon density dataset of China’s terrestrial ecosystems,the study analyses CS changes and their relationship with land use changes spanning from 1990 to *** findings indicate that the quantitative changes in land use in China from 1990 to 2020 are characterised by a reduction in the area proportion of cropland and grassland,along with an increase in the impervious surface and forest *** changing trend is projected to continue under the PCS from 2020 to *** the SSPs-RCPs scenario,the proportion of cropland and impervious surface predominantly increases,while the proportions of forest and grassland continuously *** loss in China’s carbon storage from 1990 to 2020 amounted to 0.53×10^(12)kg,primarily due to the reduced area of cropland and *** the SSPs-RCPs scenario,more significant carbon loss occurs,reaching a peak of8.07×10^(12)kg in the SSP4-RCP3.4 *** loss is mainly concentrated in the southeastern coastal area and the Beijing-TianjinHebei(BTH)region of China,with urbanisation and deforestation identified as the primary *** the future,it is advisable to enhance the protection of forests and grassland while stabilising cropland areas and improving the intensity of urban *** research findings offer valuable data support for China’s land management policy,land space optimisation,and the achievement of dual-carbon targets.

关键词： land use change Future Land Use Simulation(FLUS)model carbon storage carbon density dataset land use scenario China

Morphology and phylogenetic placement of Mallomonas vietnamica(Synurales,Chrysophyceae)from China

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Journal of Oceanology and Limnology 2024年第4期42卷 1325-1335页

作者： Junxue HAO Fangru NAN Junping LÜ Qi LIU Xudong LIU Shulian XIE Jia FENG school of life science Shanxi UniversityTaiyuan 030006China

The newly described chrysophyte,Mallomonas vietnamica,is reported for the first time in China from specimens collected in Guizhou Province,SW *** morphological characteristics were studied using light and scanning electron *** species was described based on morphological characteristics,including cell size,scale size,dome,V-rib,and ***,molecular sequencing of *** was conducted and a phylogenetic tree was constructed based on concatenated SSU,LSU,and rbc L *** phylogenetic tree led us to suggest raising a new section named Uncatusipedae for this *** study provides new molecular data from the genus Mallomonas and enriches our understanding of the species diversity and geographical distribution of the genus Mallomonas in China.

关键词： Chrysophyta Mallomonas vietnamica phylogenetic study taxonomy

Inhibition mechanisms of CRISPR-Cas9 by Acr ⅡA25.1 and AcrⅡA32

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science China life sciences 2024年第9期67卷 1781-1791页

作者： Jianlin Zheng Yuwei Zhu Tengjin Huang Wenbo Gao Jiale He Zhiwei Huang HIT Center for life sciences School of Life Science and Technology Harbin Institute of Technology Westlake Center for Genome Editing Westlake Laboratory of Life Sciences and Biomedicine School of Life Sciences Westlake University

In the ongoing arms race between bacteria and bacteriophages, bacteriophages have evolved anti-CRISPR proteins to counteract bacterial CRISPR-Cas systems. Recently, Acr ⅡA25.1 and Acr ⅡA32 have been found to effectively inhibit the activity of Spy Cas9 both in bacterial and human cells. However, their molecular mechanisms remain elusive. Here, we report the cryo-electron microscopy structures of ternary complexes formed by Acr ⅡA25.1 and Acr ⅡA32 bound to Spy Cas9-sg RNA. Using structural analysis and biochemical experiments, we revealed that Acr ⅡA25.1 and Acr ⅡA32 recognize a novel, previously-unidentified anti-CRISPR binding site on Spy Cas9. We found that both Acr ⅡA25.1 and Acr ⅡA32 directly interact with the WED domain, where they spatially obstruct conformational changes of the WED and PI domains, thereby inhibiting Spy Cas9 from recognizing protospacer adjacent motif(PAM) and unwinding double-stranded DNA. In addition,they may inhibit nuclease activity by blocking the dynamic conformational changes of the Spy Cas9 surveillance complex. In summary, our data elucidate the inhibition mechanisms of two new anti-CRISPR proteins, provide new strategies for the modulation of Spy Cas9 activity,and expand our understanding of the diversity of anti-CRISPR protein inhibition mechanisms.

关键词： anti-CRISPR cryo-EM SpyCas9 AcrIIA25.1 AcrIIA32 inhibiton

Resolving the geometric structure of trastuzumab by mobility capillary electrophoresis and native mass spectrometry

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Chinese Chemical Letters 2024年第3期35卷 221-225页

作者： Wenjing Zhang Jie Hong Lei Yang Zuqiang Xu Yu Xiang Wei Xu school of life science Beijing Institute of TechnologyBeijing 100081China

Available online Immunoglobulins G(IgGs)are Y-shaped globular proteins,however,their high flexibility and heterogeneity pose great challenges to their structure and conformation *** structure of IgG closely correlates to its biofunctions,such as the antibody escape of human immunodeficiency virus(HIV)could attribute to the distance mismatch between the ends of two Fab arms(antigen-binding sites)and envelope glycoprotein spikes on virion ***,we report the first use of mobility capillary electrophoresis(MCE)and native mass spectrometry(nMS)to resolve the internal geometric structure and conformation of an IgG(trastuzumab)in solution *** proteolysis,the ellipsoid dimensions of IgG and its subunits were measured by MCE-nMS *** was then reconstructed,in which the sizes and relative positions of these three subunits in three-dimensional space were *** was found that the two Fab arms have an angle of~102.1°and a distance of~11.0 nm between the two antigen-binding sites under native condition,and the Fc arm was tilted~16.0°towards one of the Fab *** was not on the plane of Fab-Fab,but has an angle of no larger than 103.1°.Under acidic environment(pH 3.0),each subunit of the IgG would unfold into larger dimensions,and the angles between these subunits also *** great potential for tumor imaging and therapy,the structure of F(ab')_(2)fragments was also measured and validated by molecular dynamic *** was found that the electrostatic force among these three subunits and steric hindrance stemming from Fc help maintaining the angle between two Fab arms.

关键词： Native mass spectrometry Mobility capillary electrophoresis Trastuzumab Protein structure Geometric structure

Interannual evolution of the chemical composition,sources and processes of PM_(2.5)in Chengdu,China:Insights from observations in four winters

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Journal of Environmental sciences 2024年第4期138卷 32-45页

作者： Junke Zhang Jiaqi Li Yunfei Su Chunying Chen Luyao Chen Xiaojuan Huang Fangzheng Wang Yawen Huang Gehui Wang Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Department of Environmental science&Engineering Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3)Fudan UniversityShanghai 200438China Key Lab of geographic Information science of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China

The air quality in China has improved significantly in the last decade and,correspondingly,the characteristics of PM_(2.5)have also *** studied the interannual variation of PM_(2.5)in Chengdu,one of the most heavily polluted megacities in southwest China,during the most polluted season(winter).Our results show that the mass concentrations of PM_(2.5)decreased significantly year-by-year,from 195.8±91.0μg/m~3in winter 2016 to 96.1±39.3μg/m^(3)in winter *** mass concentrations of organic matter(OM),SO_()4^(2-),NH_(4)^(+)and NO_(3)^(-)decreased by 49.6%,57.1%,49.7% and 28.7%,*** differential reduction in the concentrations of chemical components increased the contributions from secondary organic carbon and NO_(3)^(-)and there was a larger contribution from mobile *** contribution of OM and NO_(3)^(-)not only increased with increasing levels of pollution,but also increased year-by-year at the same level of *** sources of PM_(2.5)were identified:combustion sources,vehicular emissions,dust and secondary *** aerosols made the highest contribution and increased year-by-year,from 40.6%in winter 2016 to 46.3% in winter *** contrast,the contribution from combustion sources decreased from 14.4% to 8.7%.Our results show the effectiveness of earlier pollution reduction policies and emphasizes that priority should be given to key pollutants(e.g.,OM and NO_(3)^(-))and sources(secondary aerosols and vehicular emissions)in future policies for the reduction of pollution in Chengdu during the winter months.

关键词： PM_(2.5) Chemical composition Sources Interannual evolution Winter Chengdu

The autophagy protein Atg9 functions in glia and contributes to parkinsonian symptoms in a Drosophila model of Parkinson’s disease

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Neural Regeneration Research 2024年第5期19卷 1150-1155页

作者： Shuanglong Yi Linfang Wang Margaret S.Ho Shiping Zhang school of life science and Technology ShanghaiTech UniversityShanghaiChina College of life sciences University of Chinese Academy of SciencesBeijingChina

Parkinson’s disease is a progressive neurodegenerative disease characterized by motor deficits,dopaminergic neuron loss,and brain accumulation ofα-synuclein aggregates called Lewy *** in protein degradation pathways,such as autophagy,has been demonstrated in neurons as a critical mechanism for eliminating protein aggregates in Parkinson’s ***,it is less well understood how protein aggregates are eliminated in glia,the other cell type in the *** the present study,we show that autophagy-related gene 9(Atg9),the only transmembrane protein in the autophagy machinery,is highly expressed in Drosophila glia from adult *** from immunostaining and live cell imaging analysis reveal that a portion of Atg9 localizes to the trans-Golgi network,autophagosomes,and lysosomes in ***9 is persistently in contact with these *** glial atg9 reduces the number of omegasomes and autophagosomes,and impairs autophagic substrate *** suggests that glial Atg9 participates in the early steps of autophagy,and hence the control of autophagic ***,loss of glial atg9 induces parkinsonian symptoms in Drosophila including progressive loss of dopaminergic neurons,locomotion deficits,and glial *** findings identify a functional role of Atg9 in glial autophagy and establish a potential link between glial autophagy and Parkinson’s *** results may provide new insights on the underlying mechanism of Parkinson’s disease.

关键词： Atg9 autophagy glia Parkinson’s disease

Involvement of the ABA-and H_(2)O_(2)-Mediated Ascorbate-Glutathione Cycle in the Drought Stress Responses of Wheat Roots

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 329-342页

作者： Mengyuan Li Zhongye Gao Lina Jiang Leishan Chen Jianhui Ma College of life science Henan Normal UniversityXinxiang453007China school of life science and Basic Medicine Xinxiang UniversityXinxiang453003China

Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various ***,the relationship between ABA and H_(2)O_(2) levels and the AsA–GSH cycle under drought stress in wheat has not been *** this study,a hydroponic experiment was conducted in wheat seedlings subjected to 15%polyethylene glycol(PEG)6000–induced *** stress caused the rapid accumulation of endogenous ABA and H_(2)O_(2) and significantly decreased the number of root tips compared with the *** application of ABA significantly increased the number of root tips,whereas the application of H_(2)O_(2) markedly reduced the number of root tips,compared with that under 15%*** addition,drought stress markedly increased the DHA,GSH and GSSG levels,but decreased the AsA levels,AsA/DHA and GSH/GSSG ratios compared with those in the *** activities of the four enzymes in the AsA–GSH cycle were also markedly increased under drought stress,including glutathione reductase(GR),ascorbate peroxidase(APX),monodehydroascorbate reductase(MDHAR)and dehydroascorbate reductase(DHAR),compared with those in the ***,the application of an ABA inhibitor significantly inhibited GR,DHAR and APX activities,whereas the application of an H_(2)O_(2) inhibitor significantly inhibited DHAR and MDHAR ***,the application of ABA inhibitor significantly promoted the increases of H_(2)O_(2) and the application of H_(2)O_(2) inhibitor significantly blocked the increases of ABA,compared with those under 15% *** together,the results indicated that ABA and H_(2)O_(2) probably interact under drought stress in wheat;and both of them can mediate drought stress by modulating the enzymes in AsA–GSH cycle,where ABA acts as the main regulator of GR,DHAR,and APX activities,and H_(2)O_(2) acts as the main regulator of DHAR and MDHAR activities.

关键词： ABA H_(2)O_(2) AsA-GSH cycle drought stress wheat roots

Recent progress of two-dimensional metal-base catalysts in urea oxidation reaction

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Rare Metals 2024年第8期43卷 3607-3633页

作者： Qi-Xiang Huang Fang Wang Yong Liu Bi-Ying Zhang Fang-Ya Guo Zhong-Qiu Jia Hao Wang Tian-Xiang Yang Hai-Tao Wu Feng-Zhang Ren Ting-Feng Yi school of Materials science and Engineering Henan University of Science and Technology school of Environmental Engineering and Chemistry Luoyang Institute of Science and Technology Henan Province International Joint Laboratory of Materials for Solar Energy Conversion and Lithium Sodium Based Battery school of Chemistry and life sciences Suzhou University of Science and Technology school of Materials science and Engineering Northeastern University

Urea oxidation reaction(UOR) is an auxiliary water electrolysis hydrogen production technology developed in recent years to replace oxygen evolution reaction and reduce energy consumption,which can produce hydrogen more efficiently by low theoretical potential,reduce the average cost of electrochemical hydrogen production,and is a frontier research hotspot for renewable hydrogen ***-dimensional(2D) nanomaterials as electrocatalysts have many favorable potential,such as it can effectively reduce the resistivity of materials and increase the specific surface area with *** paper reviews the application of 2D materials in UOR in alkaline *** a cross-sectional comparison of various material performance data including overpotential,Tafel slope,electrochemical active surface area(ECSA) and it stability test was conducted,which could illustrate the differences between materials composed of different *** addition,the main challenges hindering the progress of research on 2D materials in urea electrocatalysis processes and promising materials in this field in future are summarized and *** is believed that this review will contribute to designing and analyzing highperformance 2D urea electrocatalysts for water splitting.

关键词： Water splitting Urea oxidation reaction Two-dimensional Transition metal compounds Nobleon-noble metals

Defect engineering on constructing surface active sites in catalysts for environment and energy applications

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Frontiers of Chemical science and Engineering 2024年第7期18卷 11-32页

作者： Yawen Cai Baowei Hu Xiangke Wang school of life science Shaoxing UniversityShaoxing 312000China College of Environmental science and Engineering North China Electric Power UniversityBeijing 102206China

The precise engineering of surface active sites is deemed as an efficient protocol for regulating surfaces and catalytic properties of *** engineering is the most feasible option to modulate the surface active sites of *** specific active sites on the catalyst allows precise modulation of its electronic structure and physicochemical ***,we outlined the engineering of several types of defects,including vacancy defects,void defects,dopant-related defects,and defect-based single atomic *** overview of progress in fabricating structural defects on catalysts via de novo synthesis or post-synthetic modification was ***,the applications of the well-designed defective catalysts in energy conversion and environmental remediation were carefully ***,current challenges in the precise construction of active defect sites on the catalyst and future perspectives for the development directions of precisely controlled synthesis of defective catalysts were also proposed.

关键词： defect engineering vacancy void defects doping single atomic sites