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Parasite-host network analysis provides insights into the evolution of two mistletoe lineages(Loranthaceae and Santalaceae)

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Plant Diversity 2023年第6期45卷 702-711页

作者： Jin Zhao Yuanjie li Xuanni Wang Manru li Wenbin Yu Jin chen ling Zhang CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303YunnanChina Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichang 443002HubeiChina Graduate School of the Chinese Academy of Sciences Beijing 100049China linnaeus Labs Technology Co. LtdWuyuan 333200JiangxiChina

Mistletoes are ecologically important parasitic plants,with> 1600 species from five lineages *** lineages exhibit distinct patterns of species diversification and host specificity,however,the mechanisms underlying these differences are poorly *** this study,we analysed a comprehensive parasite-host network,including 280 host species from 60 families and 22 mistletoe species from two lineages(Santalaceae and Loranthaceae) in Xishuangbanna,located in a biodiversity hotspot of tropical *** identified the factors that predict the infection strength of *** also detected host specificity and the phylogenetic signal of mistletoes and their *** found that this interaction network could be largely explained by a model based on the relative abundance of *** infection was positively correlated with diameter at breast height and tree coverage,but negatively correlated with wood ***,closely related mistletoe species tend to interact more often with similar ***,the two lineages showed a significantly different network *** of host generality were higher in Loranthaceae than in Santalaceae,although neither lineage showed phylogenetic signal for host *** study demonstrates that the neutral interaction hypothesis provides suitable predictions of the mistletoe-host interaction network,and mistletoe species show significant phylogenetic signals for their *** findings also indicate that high species diversification in Loranthaceae may be explained by high rates of host generality and the evolutionary history shared by Loranthaceae species with diverse host plants in the tropics.

关键词： Loranthaceae Mistletoeehost interaction Neutral interaction hypothesis Parasiteehost network Santalaceae

Pillarene-Involved Metallic Supramolecular Nanostructures

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Chinese Journal of Chemistry 2015年第3期33卷 319-328页

作者： Chang-Wei Zhang li-Jun chen Hai-Bo Yang Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of ChemistryEast China Normal UniversityShanghai 200062China

Pillarenes(or pillararenes),as a new and rapidly developing class of covalent macrocycles,have stimulated a tremendous upsurge of interest in supramolecular chemistry because of their unique features and potentials in fabri-cating functional *** addition,metallo-supramolecular chemistry has grown steadily over the last few *** presence of metal in supramolecular architectures enables the systematic tuning of their properties and endows them with optical,magnetic,and electric etcetera unusual *** marriage of these two fields offers new possibilities for the fabrication of novel functional materials and *** review article provides an over-view of recent advancements on pillararene-based metallic supramolecular *** fabrication and func-tionalities of pillararene-decorated metallic macrocycles,metal-organic frameworks(MOFs),and metal nanoparti-cles are comprehensively summarized and discussed.

关键词： self-assembly pillararene metallacycle metal−organic frameworks metal nanoparticle

Coordinated organogel templated fabrication of silver/polypyrrole composite nanowires

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Chinese Chemical Letters 2011年第1期22卷 123-126页

作者： Bo Tian li li Ming Tang Kai chen Yu Xia Xin Jin Laboratory of Advanced Materials Department of Chemical Engineering Tsinghua University beijing 100084 China

A new method to fabricate metal/conducting polymer composite nanowires is presented by taking silver/polypyrrole composite nanowires as an example. A silver （D-coordinated organogel as template was prepared firstly, and redox-polymerization of pyrrole took place on the gel fiber, giving product of silver/polypyrrole nanowires. The silver/polypyrrole nanowires were characterized by multiple techniques. This strategy could be carried out in one-step procedure at room temperature, and it proves the utility of coordinated organogels in template synthesis of polymer nanostructures.

关键词： Coordinated organogel Template polymerization Polypyrrole Composite nanowires

Anisotropic diffusion of volatile pollutants at air-water interface

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Water Science and Engineering 2013年第2期6卷 153-163页

作者： li-ping chen Jing-tao chenG Guang-fa DENG College of Urban Construction and Safety Engineering Nanjing University of Technology Jiangsu Frontier Electric Technology Co. Ltd.

The volatile pollutants that spill into natural waters cause water pollution. Air pollution arises from the water pollution because of volatilization. Mass exchange caused by turbulent fluctuation is stronger in the direction normal to the air-water interface than in other directions due to the large density difference between water and air. In order to explore the characteristics of anisotropic diffusion of the volatile pollutants at the air-water interface, the relationship between velocity gradient and mass transfer rate was established to calculate the turbulent mass diffusivity. A second-order accurate smooth transition differencing scheme （STDS） was proposed to guarantee the boundedness for the flow and mass transfer at the air-water interface. Simulations and experiments were performed to study the trichloroethylene （C2HC13） release. By comparing the anisotropic coupling diffusion model, isotropic coupling diffusion model, and non-coupling diffusion model, the features of the transport of volatile pollutants at the air-water interface were determined. The results show that the anisotropic coupling diffusion model is more accurate than the isotropic coupling diffusion model and non-coupling diffusion model. Mass transfer significantly increases with the increase of the air-water relative velocity at a low relative velocity. However, at a higher relative velocity, an increase in the relative velocity has no effect on mass transfer.

关键词： volatile pollutant," interfacial mass transfer anisotropic diffusion STDS anisotropic coupling diffusion model

Analysis of Dynamic Tensile Process of Fiber Reinforced Concrete by Acoustic Emission Technique

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Journal of Wuhan University of Technology(Materials Science) 2018年第5期33卷 1129-1139页

作者： WANG Yan chen Shijie GE Lu ZHOU li HU Hongxiang College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China Shenzhen Municipal Design&Research Institute Co. LtdShenzhen 518029China ChongQing Municipal Designing Research Institute ChongQing 400020China

The fiber reinforced concrete has good dynamic mechanical properties. But corresponding research lacks the dynamic damage characteristics of the polypropylene fiber（fiber of low elastic modulus） and steel fiber（fiber of high elastic modulus） reinforced concrete under medium strain rate（10-6 s-1-10-4 s-1）. In order to study the effect of strain rate on the damage characteristics of fiber reinforced concrete during the full curve damage process, the real time dynamic acoustic emission（AE） technique was applied to monitor the damage process of fiber reinforced concrete at three strain rates. The AE wavelet energy spectrum in ca8 frequency band and average AE peak frequency at three strain rates were analyzed. With the accumulation of damage, the AE wavelet energy spectrum in ca8 frequency band increased first and then decreased, and the average AE peak frequency increased gradually. With the increase of strain rate, the AE wavelet energy spectrum in ca8 frequency band and average AE peak frequency decreased gradually. The polypropylene fiber content has more obvious effect on the Dynamic increase factor（DIF） of the peak stress than the steel fiber content. The theoretical basis was provided for the monitoring of dynamic damage of fiber reinforced concrete based on the AE technique.

关键词： acoustic emission steel fiber polypropylene fiber strain rate acoustic emission wavelet energy spectrum peak frequency

Rosgen stream classification and fluvial processes of the Shiyang River,China

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Journal of Mountain Science 2024年第11期21卷 3886-3897页

作者： li Ping GAO Hongshan li Zongmeng WU Yajie liU Fenliang YAN Tianqi chen Yingying College of Resources and Environment Xizang Agriculture and Animal Husbandry UniversityNyingchi 860000China Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Henan Key Laboratory for Synergistic Prevention of Water and Soil Environmental Pollution School of Geographic SciencesXinyang Normal UniversityXinyang 464000China Wuwei No.1 Middle School Wuwei 733000China School of Municipal and Surveying Engineering Hunan City UniversityYiyang 413000China

The Shiyang River is an important ecological pillar in northwest China,sustaining Minqin oasis and its surrounding ***,the basin has long been plagued by water scarcity and ecological *** the river classification is critical for understanding the complexity,diversity,and ecological functions of rivers,and the foundation of river management and watershed ecological restoration,it has not received adequate attention in this *** obtain a deeper and comprehensive understanding of the Shiyang River,this study utilizes the Rosgen stream classification system to assess the river morphology,geomorphic features,and hydrologic *** results showed that seven first-level and fourteen second-level river types can be identified along 53 river sections of the Shiyang *** comparison analysis on the hydrologic parameters for each river type demonstrated a strong positive correlation between discharge and all river *** discharge increased,channels with moderate to high width/depth ratios experienced significant lateral adjustments.A consistent channel gradient,coupled with higher discharge,facilitated the transition from single to multiple *** tendencies were more pronounced in rivers where riverbeds were wider and shallower with higher stream ***,water-flow shear stress decreased with the increase in the width/depth *** study offered critical insights into the Shiyang River’s forms and processes and for the river management and ecological restoration practices.

关键词： Rosgen stream classification Fluvial Processes Geometric Channel Parameters The Shiyang River

African swine fever and meat prices fluctuation:An empirical study in China based on TVP-VAR model

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Journal of Integrative Agriculture 2021年第8期20卷 2289-2301页

作者： li Hui-shang HU chen-pei LÜZheng li Mei-qi GUO Xin-zhu Agricultural Information Institute/Key Laboratory of Big Agri-Data of Ministry of Agriculture and Rural Affairs Chinese Academy of Agricultural SciencesBeijing 100081P.R.China International Statistical Information Center National Bureau of StatisticsBeijing 100826P.R.China School of Statistics and Mathematics Central University of Finance and EconomicsBeijing 100081P.R.China

African swine fever(ASF),a fatal disease outbroken in China in August 2018,has widely attracted social concern especially in the information *** occurrence of ASF led to an imbalance between supply and demand in pork and other meat *** a result,meat prices fluctuated greatly during the past year in *** measure ASF quantitatively,the internet public concern index about ASF was created using web crawler *** relationships between ASF and meat prices were analyzed based on time-varying parameter vector auto-regressive(TVP-VAR)*** results showed that there were some differences in the impact size,direction and duration of ASF on the prices of pork,chicken,beef and mutton,and the characteristics of time variability and heterogeneity were *** the same time,the impact of ASF on meat prices is not consistent with the trend and degree of *** impulse intensity is strongly correlated with the strength and duration of ASF,and it is generally weak in the early stage and much stronger in the middle and late *** results indicate that macro regulations,monitoring and early-warning system,standardizing production and circulation,and the public opinion monitoring and guidance about ASF should be given more attention in future to stabilize the market expectations and to promote a smooth functioning of the livestock markets.

关键词： African swine fever meat prices dynamic transmission TVP-VAR model

A single silk-and multiple pollen-expressed PMEs at the Ga1 locus modulate maize unilateral cross-incompatibility

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Journal of Integrative Plant Biology 2023年第5期65卷 1344-1355页

作者： Zhaogui Zhang Kai li Huairen Zhang Qiuxia Wang li Zhao Juan liu Huabang chen State Key Laboratory of Plant Cell and Chromosome Engineering Innovative Academy of Seed DesignInstitute of Genetics and Developmental Biologythe Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The Gametophyte factor1(Ga1) locus in maize confers unilateral cross-incompatibility(UCI), and it is controlled by both pollen and silk-specific determinants. Although the Ga1 locus has been reported for more than a century and is widely utilized in maize breeding programs, only the pollen-specific ZmGa1P has been shown to function as a male determinant;thus, the genomic structure of the Ga1 locus and all the determinants that control UCI at this locus have not yet been fully ***, we used map-based cloning to confirm the determinants of UCI at the Ga1 locus and maize pan-genome sequence data to characterize the genomic structure of the Ga1 locus. The Ga1 locus comprises one silk-expressed pectin methylesterase gene(PME, ZmGa1F) and eight pollenexpressed PMEs(ZmGa1P and ZmGa1PL1-7).Knockout of ZmGa1F in Ga1/Ga1 lines leads to the complete loss of the female barrier function. The expression of individual ZmGa1PL genes in a ga1/ga1 background endows ga1 pollen with the ability to overcome the female barrier of the Ga1 locus. These findings, combined with genomic data and genetic analyses, indicate that the Ga1 locus is modulated by a single female determinant and multiple male determinants, which are tightly *** results of this study provide valuable insights into the genomic structure of the Ga2 and Tcb1 loci and will aid applications of these loci in maize breeding programs.

关键词： Gametophyte factor1 maize unilateral cross-incompatibility ZmGa1F ZmGa1PL

Metabolic engineering of yeasts for green and sustainable production of bioactive ginsenosides F2 and 3β,20S-Di-O-Glc-DM

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Acta Pharmaceutica Sinica B 2022年第7期12卷 3167-3176页

作者： Fenglin Jiang chen Zhou Yan li Haidong Deng Ting Gong Jingjing chen Tianjiao chen Jinling Yang Ping Zhu State Key Laboratory of Bioactive Substance and Function of Natural Medicines NHC Key Laboratory of Biosynthesis of Natural ProductsCAMS Key Laboratory of Enzyme and Biocatalysis of Natural DrugsInstitute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Both natural ginsenoside F2 and unnatural ginsenoside 3β,20S-Di-O-Glc-DM were reported to exhibit anti-tumor *** approaches for producing them rely on direct extraction from Panax ginseng,enzymatic catalysis or chemical synthesis,all of which result in low yield and high *** engineering of microbes has been recognized as a green and sustainable biotechnology to produce natural and unnatural *** we engineered the complete biosynthetic pathways of F2 and 3β,20S-Di-OGlc-DM in Saccharomyces cerevisiae via the CRISPR/Cas9 *** titers of F2 and 3β,20S-Di-O-GlcDM were increased from 1.2 to 21.0 mg/L and from 82.0 to 346.1 mg/L at shake flask level,respectively,by multistep metabolic engineering ***,pharmacological evaluation showed that both F2and 3β,20S-Di-O-Glc-DM exhibited anti-pancreatic cancer activity and the activity of 3β,20S-Di-O-GlcDM was even ***,the titer of 3β,20S-Di-O-Glc-DM reached 2.6 g/L by fed-batch fermentation in a 3 L *** our knowledge,this is the first report on demonstrating the anti-pancreatic cancer activity of F2 and 3β,20S-Di-O-Glc-DM,and achieving their de novo biosynthesis by the engineered *** work presents an alternative approach to produce F2 and 3β,20S-Di-O-Glc-DM from renewable biomass,which lays a foundation for drug research and development.

关键词： Ginsenoside UDP-glycosyltransferase Metabolic engineering Synthetic biology Saccharomyces cerevisiae CRISPR/Cas9 system Microbial cell factory Anti-pancreatic cancer activity