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The crystal structure of (Fe_(4)Cr_(4)Ni)_(9)C_(4)

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Science china Earth Sciences 2005年第3期48卷 338-345页

作者： shi {1.1. ma {2.1, XIONG Ming1. DAI Mingquan1. BAI Wenji2, FANG Qingsong2, YAN Binggang2 & YANG Jingsui2.1. X-ray Diffraction Laboratory, china university of geosciences, Beijing 1.0083. china 2. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 1.0037, china 1. X-ray Diffraction Laboratory China University of Geosciences 100083 Beijing China 2. Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

(Fe4Cr4Ni)9C4 is a metal carbide mineral formed by combination of Fe, Cr and Ni with C. It occurs in a chromite deposit in the Luobusha ophiolite, Tibet. Based on the determina- tion of its crystal structure, the empirical formula is (Fe4.1.Cr3.84Ni0.96)8.92C3.70 and the simplified formula is (Fe4Cr4Ni)4C9. The mineral is hexagonal with a = 1.38392(2) nm, c = 0.44690(9) nm, space group P63 m c, Z=6 and the calculated specific gravity Dx = 7.089 g/cm3. Fe, Cr and Ni occupy different crystallographic sites and their coordination numbers are approximately 1., forming an alternate stacking sequence of flat and puckered layers along the c axis. Some me- tallic atoms have a defect structure. The interatomic distances of Fe, Cr and Ni are 0.2525— 0.2666 nm, and the distances between Fe, Cr, Ni and C are 0.1.93—0.21.9 nm. The coordina- tion number of carbon is 6. It occurs in interstices of the metallic atoms Fe, Cr and Ni to form trigonal-prismatically coordinated polyhedra. These coordination polyhedra are linked with each other via shared corners or shared edges into a new type of metal carbide structure.

关键词： Luobusha of Tibet, metal carbide, crystal structure.

Response of phytoplankton functional group to spring drought in a large subtropical reservoir

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Journal of Oceanology and Limnology 2024年第5期42卷 1586-1596页

作者： Yue WU Qi ye Siwen CHEN Kaining CHEN Shuzhan ma Yiheng CHANG Xiaoli {1. State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China university of Chinese Academy of Sciences Beijing 100049China State Environmental Protection Key Laboratory of Aquatic Ecosystem Health in the Middle and Lower Reaches of Yangtze River Jiangsu Provincial Academy of Environmental ScienceNanjing 210036China

Global warming has caused an increase in the frequency and duration of droughts *** could trigger large changes in physico-chemical conditions and phytoplankton community in waterbodies,resulting in a shift in the phytoplankton *** diatom blooms in reservoirs have been increasingly observed in the past decade in the Taihu Lake *** aim of the present study is to elucidate the impacts of droughts on aquatic environment and to determine the driving factors for the succession of the phytoplankton functional groups based on the analysis of data collected during spring from 2009 to 2020 in the Daxi *** unimodal relationship between 1.month aggregated precipitation index and phytoplankton species richness indicated the competitive exclusion occurred in extremely drought *** structural equation modeling indicated that drought-related low water level conditions intensified sediment resuspension,and increased the phosphorus-enriched nonalgal turbidity in the Daxi ***,a steady shift in the Reynolds phytoplankton functional groups from L 0,TD,J,X 2,and A(phytoplankton taxa preferring low turbidity and nutrient conditions)to TB(pennate diatoms being adapt to turbid and nutrient-rich conditions)was *** increased TP and non-algal turbidity in addition to the lowered disturbance contribute to the prevalence of Group *** the difficulties in nutrient control,timely water replenishment is often a feasible method of controlling the dominance of harmful algae for reservoir ***,alternative water sources are in high demand for ensuring ecological safety and water availability when dealing with drought.

关键词： drought reservoir sediments resuspension phytoplankton functional group diatom

Homozygous CCDC1.6 mutation causes oligoasthenoteratozoospermia in humans and mice

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Zoological Research 2024年第5期45卷 1073-1087页

作者： Jing-Wei ye Tanveer Abbas Jian-Teng Zhou Jing Chen Meng-Lei Yang Xiong-Heng Huang Huan Zhang Hui ma Ao ma Bo Xu Ghulam Murtaza Qing-Hua shi Bao-Lu shi Division of Reproduction and Genetics First Affiliated Hospital of University of Science and Technology of ChinaHefei National Laboratory for Physical Sciences at MicroscaleSchool of Basic Medical SciencesDivision of Life Sciences and MedicineBiomedical Sciences and Health Laboratory of Anhui ProvinceInstitute of Health and MedicineHefei Comprehensive National Science CenterUniversity of Science and Technology of ChinaHefeiAnhui 230026China Institute of Andrology Nanjing Drum Tower HospitalAffiliated Hospital of Nanjing University Medical SchoolNanjingJiangsu 210008China

Infertility represents a significant health concern,with sperm quantity and quality being crucial determinants of male ***(OAT)is characterized by reduced sperm motility,lower sperm concentration,and morphological abnormalities in sperm heads and *** variants in several genes have been implicated in OAT,its genetic etiologies and pathogenetic mechanisms remain inadequately *** this study,we identified a homozygous nonsense mutation(c.91.C>T,***306*)in the coiled-coil domain containing 1.6(CCDC1.6)gene in an infertile male patient with *** mutation resulted in the production of a truncated CCDC1.6 protein(amino acids 1.305),retaining only two out of five coiled-coil *** validate the pathogenicity of the CCDC1.6 mutation,we generated a mouse model(Ccdc1.6^(mut/mut))with a similar mutation to that of the ***,the Ccdc1.6mut/mut mice exhibited infertility,characterized by significantly reduced sperm counts,diminished motility,and multiple defects in sperm heads and ***,the levels of axonemal proteins,including DNAH1.,DNAH1.and SPAG6,were significantly reduced in the sperm of Ccdc1.6^(mut/mut) ***,both human and mouse CCDC1.6 interacted with intraflagellar transport protein 20(IFT20),but this interaction was lost in the mutated versions,leading to the degradation of *** study identified a novel deleterious homozygous nonsense mutation in CCDC1.6 that causes male infertility,potentially by disrupting axonemal protein *** findings offer valuable insights for genetic counseling and understanding the mechanisms underlying CCDC1.6 mutant-associated infertility in human males.

关键词： Oligoasthenoteratozoospermia Human infertility Sperm flagellum CCDC1.6 Intraflagellar transport IFT20

Targeting CXCR4 and EDN1.for the treatment of recurrent miscarriage using stearic acid from traditional Chinese medicine

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Traditional Medicine Research 2024年第11期9卷 65-75页

作者： Fang Liu Dong-Mei shi Wen-ye {1. Da-Wei Tang Gang Bai Xin-You Yu Reproductive Center of Yinchuan maternal and Child Health Hospital Yinchuan 750001China Prenatal Diagnosis Center of Ningxia Medical university General Hospital Yinchuan 750004China

Background:Recurrent miscarriage(RM)affects an estimated 1.3%of couples attempting to conceive,and its molecular components stay ineffectively caught *** study aims to explore potential therapeutic targets for RM by examining gene expression patterns and biological pathways in both mouse and human RM ***,explore relevant traditional Chinese medicine(TCM)components targeting potential therapeutic ***:We utilized the GSE2.1.51.mouse and the GSE26787 human datasets,employing gene set enrichment analysis and gene metaphysics analysis to examine differentially expressed genes and enriched ***-cell RNA analysis uncovered cellular heterogeneity and arranged pharmacology-mapped potential drug-target *** employed molecular docking strategies to assess the affinity of TCM components for key ***:In the mouse model,genes such as Ly6f1.and Gpr26 were upregulated,while Stc5a and Galca exhibited *** set enrichment analysis identified key pathways,including the tumor necrosis factor-mediated signaling *** human samples,Gene Ontology analysis highlighted processes such as apoptosis and cell ***-cell RNA analysis revealed distinct cellular populations between normal and RM *** pharmacology identified C-X-C motif chemokine receptor 4(CXCR4)and endothelin 1.EDN1.as potential key targets,and molecular docking confirmed that stearic acid from TCM appears to regulate these ***:This study presents a comprehensive analysis of the genetic and cellular underpinnings of RM,identifying CXCR4 and EDN1.as promising therapeutic *** acid from TCM could provide targeted treatment by modulating these key proteins,paving the way for new RM treatment strategies.

关键词： RM gene expression single-cell RNA analysis CXCR4 EDN1 stearic acid

Crystal Structure of Natural Non-metamict Ti- and Fe2+-rich Chevkinite-（Ce）

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Acta Geologica Sinica(English Edition) 2005年第3期 325-331页

作者： LI Guowu1.YANG Guangming2,ma Zhengsheng1.{1. nicheng1.XIONG Ming1.FAN Haifu3 and SHENG Ganfu4 1.china university of geosciences(Beijing),Beijing 1.0083.2 china university of geosciences(Wuhan),Wuhan,Hubei 430074 3 Institute of Physics,Chinese Academy of Sciences,Beijing 1.0080 4 Chengdu Institute of Geology and Mineral Resources,Chengdu,Sichuan 61.082

The crystal structure of non-metamict Ti- and Fe2+-rich chevkinite-(Ce) has been redetermined with the single -crystal sample collected from Bayan Obo, Inner Mongolia, china. The chemical formula of the sample is Ce4Fe2Ti3Si4O22. The crystals are monoclinic with the unit cell parameters a = 1..4656(1.) ?, b = 5.7356(6) ?, c = 1..0977(1.) ?, β= 1.0.636(2)o, V = 842.39 (1.) ?3 and Z = 2. The structures of Ti- and Fe2+-rich chevkinite-(Ce) were refined with space groups P21.a and C2/m. Least-squares refinement results show that both structural models of Ti- and Fe2+-rich chevkinite-(Ce) are very good, R[F2>2σ(F2)] =0.027 with P21.a and R[F2>2σ(F2)] =0.021.with C2/m. In order to illustrate the relation{1.p between the two space groups P21.a and C2/m, the distribution of diffraction intensities was inspected. Pseudo extinction was found, i.e., reflections with h+k=2n are systematically strong, while those with h+k=2n+1.are weak. By neglecting the systematically weak (h+k=2n+1. reflections the space group becomes C2/m. There is a mirror plane in the C2/m perpendicular to the b axis. However, oxygen atoms in the P21.a model are of a symmetrical relation{1.p with the corresponding pseudo mirror plane. It is concluded that the crystal structure of non-metamict Ti- and Fe2+-rich chevkinite-(Ce) is a superstructure with the space group of P21.a, which is of pseudo symmetry corresponding to the space group C2/m.

关键词： non-metamict Ti- and Fe2+-rich chevkinite-(Ce) crystal structure space group superstructure

Oxygen‑Coordinated Single Mn Sites for Efficient Electrocatalytic Nitrate Reduction to Ammonia

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Nano-Micro Letters 2024年第1期16卷 147-159页

作者： Shengbo Zhang Yuankang Zha Yixing ye Ke Li Yue Lin Lirong Zheng Guozhong Wang Yunxia Zhang Huajie Yin Tongfei shi Haimin Zhang Laboratory of materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031People’s Republic of China university of Science and Technology of {1. Hefei 230026People’s Republic of China Key Laboratory of Agricultural Sensors Ministry of AgricultureSchool of Information and ComputerAnhui Agricultural UniversityHefei 230026People’s Republic of China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026People’s Republic of China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadBeijing 100049People’s Republic of China

Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental ***,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption *** a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1.76.9±62.6μg h^(−1.cm^(−2)at−0.7 V(*** hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(***)under ambient ***,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1.cm^(−2)at a current density of 1.0 ma cm−2,2.5 times of that in the H *** in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.

关键词： Atomically dispersed Oxygen coordination Nitrate reduction reaction In situ spectroscopic studies Hydrogen evolution reaction

Silicon-rutile - an ultra-high pressure (UHP) mineral from an ophiolite

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Progress in Natural Science:materials International 2003年第7期 50-53页

作者： YANG Jingsui , BAI Wenji, FANG Qingsong, YAN Binggang, shi {1., ma zhesheng, DAI Mingquan and XIONG Ming (1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 1.0037, china 2. Geological university of china, Beijing 1.0083. china) Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Geological university of {1. Beijing 100083 China

Silicon(Si)-rutile separated from the Luobusa podiform chromitite in the Yarlung Zangbo ophiolite of southern Tibet is typically about 50 μm × 50 μm × 200 μm in size and consists mainly of SiO2 and TiO2- The average mineral formula is (Ti0. 82Si0.1.)O2. Powder X-ray diffraction data show that it is tetragonal in form, and the unit cell dimensions and other parameters are: α= 4. 591.2) A , c = 2.946(2)A, v=62.09(5)A3, c/α=0.641., with a molar volume about 5 % smaller than rutile (JCPDS, 21.1.76). The Si4 + ions in silicon rutile are six-coordinated, and are substituted for Ti + in the rutile structural sites. The Si-rutile, along with other associated ultra-high minerals discovered in the chromitite, such as octahedral silicate, silicon-magnesium spinel (Si4+ ions are six-coordinated), diamond, and intergrown of SiO2 and FeO phases, probably originated from the transition zone or the lower mantle, and were brought to shallow levels beneath an oceanic spreading ridge by an upwelling superplurne.

关键词： Si-rutile UHP minerals ophiolite lower mantle chromitite.

Titanium, Ti, A New Mineral Species from Luobusha, Tibet, china

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Acta Geologica Sinica(English Edition) 2013年第5期87卷 1275-1280页

作者： FANG Qingsong BAI Wenji YANG Jingsu RONG He shi {1. LI Guowu XIONG Ming ma zhesheng Institute of Geology CAGS X-ray Diffraction Laboratory China University of Geosciences

We describe the new mineral species titanium, ideally Ti, found in the podiform chromitites of the Luobusha ophiolite in Tibet, People＇s Republic of china. The irregular crystals range from 0.1.to 0.6 mm in diameter and form an intergrowth with coesite and kyanite. Titanium is silver grey in colour, the luster is metallic, it is opaque, the streak is grayish black, and it is non-fluorescent. The mineral is {1.lleable, has a rough to hackly fracture and has no apparent cleavage. The esti{1.ted Mohs hardness is 4, and the calculated density is 4.503 g/cm3. The composition is Ti 99.23-1.0.00 wt%. The mineral is hexagonal, space group P6flmmc. Unit-cell parameters are a 2.950 （2） ~, c 4.686 （1. A,V 35.32 （5） A3, Z = 2. The five strongest powder diffraction lines [d in A （hkl）（I/I0）] are： 2.569 （01.）（32）, 2.254（01.）（1.0）, 1.730 （01.）（1.）, 1.478 （1.0）（21., and 0.9464 （1.1. （8）. The species and name were approved by the CNMNC （I{1. 2.1.-044）.

关键词： Titanium new mineral species Ti chromitite Luobusha ophiolite Tibet

AlphaFold-guided redesign of a plant pectin methylesterase inhibitor for broad-spectrum disease resistance

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Molecular Plant 2024年第9期17卷 1344-1368页

作者： yeqiang Xia Guangzheng Sun Junhua Xiao Xinyi He Haibin Jiang Zhichao Zhang Qi Zhang Kainan Li Sicong Zhang Xuechao shi Zhaoyun Wang Lin Liu Yao Zhao Yuheng Yang Kaixuan Duan Wenwu ye Yiming Wang Suomeng Dong Yan Wang Zhenchuan {1. Yuanchao Wang Department of Plant Pathology Nanjing Agricultural UniversityNanjingJiangsu 210095China Key Laboratory of Soybean Disease and Pest Control(Ministry of Agriculture and Rural Affairs) Nanjng Agricultural UniversityNanjngJiangsu 210095China Anhui Province Key Laboratory of Crop Integrated Pest management Anhui Agricultural UniversityHefei 230036China School of Bioengineering Dalian University of TechnologyDalian 116024China State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBejing 100193China These authors contributed equally to the article.

Plant cell walls are a critical site where plants and pathogens continuously struggle for physiological *** we show that dynamic remodeling of pectin methylesterification of plant cell walls is a compo-nent of the physiological and co-evolutionary struggles between hosts and pathogens.A pectin methyles-terase(PsPME1.secreted by Phytophthora sojae decreases the degree of pectin methylesterification,thus synergizing with an endo-polygalacturonase(PsPG1.to weaken plant cell *** counter PsPME1.mediated susceptibility,a plant-derived pectin methylesterase inhibitor protein,GmPMl1.protects pectin to maintain a high methylesterification ***1.protects plant cell walls from enzymatic degrada-tion by inhibiting both soybean and *** pectin methylesterases during ***,constitutive expression of GmPMl1.disrupted the trade-off between host growth and defense *** therefore used AlphaFold structure tools to design a modified form of GmPMI1.GmPMI1.)that specifically targets and inhibits pectin methylesterases secreted from pathogens but notfrom *** expression of GmPMi1. enhanced plant resistance to oomycete and fungal *** summary,our work highlights the biochemical modification of the cell wall as an important focal point in the physiological and co-evolutionary conflict between hosts and microbes,providing an important proof of concept that Al-driven structure-based tools can accelerate the development of new strategies for plant protection.

关键词： apoplastic immunity AlphaFold-guided redesign broad-spectrum disease resistance pectin methyl-esteraseinhibitor cell wall