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Chinese Science Bulletin 2007年第18期52卷 2514-2521页

作者： LIU WeiZhong HU Yong ZHANG RunJie ZHOU WeiWei ZHU JiaYing LIU XiangLin HE yikun College of Life Science Capital Normal University Beijing 100037 China College of Life Science Shanxi Normal University Linfen 041004 China College of Life Science Shanxi Normal University Linfen 041004 China

MinD is a ubiquitous ATPase that plays a crucial role in selection of the division site in eubacteria, chloroplasts, and probably Archaea. In four green algae, Mesostigma viride, Nephroselmis olivacea, Chlorella vulgaris and Prototheca wickerhamii, MinD homologues are encoded in the plastid genome. However, in Arabidopsis, MinD is a nucleus-encoded, chloroplast-targeted protein involved in chloro- plast division, which suggests that MinD has been transferred to the nucleus in higher land plants. Yet the lateral gene transfer (LGT) of MinD from plastid to nucleus during plastid evolution remains poorly understood. Here, we identified a nucleus-encoded MinD homologue from unicellular green alga Chlamydomonas reinhardtii, a basal species in the green plant lineage. Overexpression of CrMinD in wild type E. coli inhibited cell division and resulted in the filamentous cell formation, clearly demon- strated the conservation of the MinD protein during the evolution of photosynthetic eukaryotes. The transient expression of CrMinD-egfp confirmed the role of CrMinD protein in the regulation of plastid division. Searching all the published plastid genomic sequences of land plants, no MinD homologues were found, which suggests that the transfer of MinD from plastid to nucleus might have occurred be- fore the evolution of land plants.

关键词：衣藻叶绿体 CrMinD基因基因转移植物进化

Stability analysis of a hybrid flexible-rigid pipe conveying fluid

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Acta Mechanica Sinica 2022年第2期38卷 141-153,I0005页

作者： yikun Wang Ziyang Hu Lin Wang Tao Qin Mo yang Qiao Ni School of Mechanical Engineering Hubei University of Arts and ScienceXiangyang 441053China Department of Engineering Mechanics Huazhong University of Science and TechnologyWuhan 430074China

The stability and dynamical behavior of flexible and articulated rigid pipes conveying fluid have attracted the attention of many researchers in the field of fluid-structure *** system of an articulated pipe composed of a flexible pipe and a rigid pipe is a class of hybrid flexible-rigid dynamical problems involving flow-induced *** paper establishes the governing equations of motion of a hybrid flexible-rigid pipe system based on Hamilton's principle,with the rigid pipe being hinged to the lower end of a flexible cantilevered pipe via a rotational *** coupling equations of motion are discretized via a Galerkin's *** mathematical model is validated by comparing the eigenvalue branches of a degenerated system by choosing extreme values of the parameters of the hybrid pipe with previous *** the theoretical analysis,the critical flow velocities are calculated as a function of the stiffness of the rotational spring,mass ratio and length ratio of the rigid and flexible *** unstable modes are detected from the eigenvalue branches and compared with those of a flexible cantilevered *** results show that the critical flow velocity is greatly influenced by several structural *** is found that a small stiffness of the rotational spring tends to predict higher-mode instability,whereas a large rotational spring stiffness would generate a second-mode instability in most *** several system parameter spaces,the hybrid pipe may experience a transference of unstable modes with the increase of flow *** is also shown that the hybrid pipe system may lose stability first in the fourth mode in some *** of the fresh results obtained for the hybrid pipe system are expected to be helpful in understanding and controlling the dynamical responses of hybrid flexible-rigid fluid-conveying pipes.

关键词： Hybrid flexible-rigid pipe Flow-induced vibration Eigenvalue Critical flow velocity Flutter

Model-Based Identification of Mechanical Characteristics of Sinosaurus(Theropoda) Crests

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 1-11页

作者： XING Lida WANG yikun Eric SNIVELY ZHANG Jianping DONG Zhiming Michael E.BURNS Philip J.CURRIE School of the Earth Sciences and Resources China University of Geosciences Auckland Bioengineering Institute The University of Auckland Department of Mechanical Engineering Ohio University Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Department of Biological Sciences University of Alberta Alberta T6G 2E9 Canada

The paired cranial crests of Sinosaurus （Theropoda） have been hypothesized as too weak to resist mechanical loads during combat. Finite element analysis （FEA） is used to test this hypothesis, first with geometry obtained through direct laser scanning of a well-preserved fossil of the crest, and then with two conceptual FE models of both crests analyzing the structure-deformation effects of fenestration. In the original fossil model, under direct loading on the dorsal faces of the crest, we found that the areas surrounding cavities on the crest experience shear stress that implies a high chance of material failure - the fracture of bone. In the conceptual model, a series of computational studies were conducted with varying loading directions. One simulation found that the shear stress and strain in the material around the cavity presented more deformation compared with the conceptual model without the cavities, and under this morphologically realistic scenario the loading conditions would result in local bone fractures. These model-based computational results indicate that the crest could not resist high loads, because it could not effectively decentralize the loading stress. Future investigations need to focus on more comprehensive computational experiments with more conditions, e.g. dynamical loading conditions, and direct palaeontological evidence.

关键词： Dinosauria Sinosaurus behavior finite element analysis

Atomically dispersed N-coordinated Fe-Fe dual-sites with enhanced enzyme-like activities

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Nano Research 2022年第2期15卷 959-964页

作者： Lei Jiao Wei Ye yikun Kang Yu Zhang Weiqing Xu Yu Wu Wenling Gu Weiyu Song Yujie Xiong Chengzhou Zhu Key Laboratory of Pesticide and Chemical Biology of Ministry of Education International Joint Research Center for Intelligent Biosensing Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan 430079China College of Material Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou 311121China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Hefei National Laboratory for Physical Sciences at the Microscale Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)School of Chemistry and Materials Scienceand National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefei 230026China

Replacement of enzymes with nanomaterials such as atomically dispersed metal catalysts is one of the most crucial steps in addressing the challenges in *** the breakthroughs of single-atom catalysts in enzyme-mimicking,a fundamental investigation on the development of an instructional strategy is still required for mimicking biatomic/multiatomic active sites in natural enzymes and constructing synergistically enhanced metal atom active ***,Fe_(2)NC catalysts with atomically dispersed Fe-Fe dual-sites supported by the metal-organic frameworks-derived nitrogen-doped carbon are employed as biomimetic catalysts to perform proof-of-concept *** effect of Fe atom number toward typical oxidase(cytochrome C oxidase,NADH oxidase,and ascorbic acid oxidase)and peroxidase(NADH peroxidase and ascorbic acid peroxidase)activities is systematically evaluated by experimental and theoretical investigations.A peroxo-like O_(2) adsorption in Fe_(2)NC nanozymes could accelerate the O-O activation and thus achieve the enhanced enzyme-like *** work achieves the vivid simulation of the enzyme active sites and provides the theoretical basis for the design of high-performance *** a concept application,a colorimetric biosensor for the detection of S^(2-) in tap water is established based on the inhibition of enzyme-like activity of Fe_(2)NC nanozymes.

关键词： nanozymes atomically dispersed dual-metal sites oxidase-like activities single-atom catalysis sensors

A bioactive nanocomposite integrated specific TAMs target and synergistic TAMs repolarization for effective cancer immunotherapy

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Bioactive Materials 2024年第8期38卷 472-485页

作者： Wei Gu Wen Guo Zhishuang Ren Yimeng Zhang Meiqi Han Qinfu Zhao yikun Gao Yuling Mao Siling Wang Department of Pharmaceutics School of PharmacyShenyang Pharmaceutical University103 Wenhua RoadShenyangLiaoning Province110016China School of Life Sciences and Biopharmaceuticals Shenyang Pharmaceutical University103 Wenhua RoadShenyangLiaoning Province110016China

Reactive oxygen species(ROS)generated from photosensitizers exhibit great potential for repolarizing immunosuppressive tumor-associated macrophages(TAMs)toward the anti-tumor M1 phenotype,representing a promising cancer immunotherapy ***,their effectiveness in eliminating solid tumors is generally limited by the instability and inadequate TAMs-specific targeting of ***,a novel core-shell integrated nano platform is proposed to achieve a coordinated strategy of repolarizing TAMs for potentiating cancer *** mesoporous silica nanoparticles(CMSN)are fabricated to encapsulate photosensitizer-Indocyanine Green(ICG)to improve their *** ginseng-derived exosome(GsE)was coated on the surface of ICG/CMSN for targeting TAMs,as well as repolarizing TAMs concurrently,named ICG/CMSN@*** expected,with the synergism of ICG and GsE,ICG/CMSN@GsE exhibited better stability,mild generation of ROS,favorable specificity toward M2-like macrophages,enhancing drug retention in tumors and superior TAMs repolarization potency,then exerted a potent antitumor *** vivo,experiment results also confirm the synergistic suppression of tumor growth accompanied by the increased presence of anti-tumor M1-like macrophages and maximal tumor *** together,by integrating the superiorities of TAMs targeting specificity and synergistic TAMs repolarization effect into a single nanoplatform,ICG/CMSN@GsE can readily serve as a safe and high-performance nanoplatform for enhanced cancer immunotherapy.

关键词： Ginseng-derived exosome Colloidal mesoporous silica nanoparticles Tumor-associated macrophages TAMs-specific targeting delivery Repolarizing TAMs

Enzyme-activatable disk-shaped nanocarriers augment tumor permeability for breast cancer combination therapy

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Nano Research 2024年第7期17卷 6400-6410页

作者： Hanming Zhang Honglin Gao Yicong Zhang yikun Han Qing Lin Tao Gong Xun Sun Zhirong Zhang Ling Zhang Shiqi Huang Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry West China School of PharmacySichuan UniversityChengdu 610041China Med-X Center for Materials College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China

Unique physiopathological characteristics of tumor tissues impose obstacles to the sufficient penetration of traditional nanomedicines,resulting in undesirable drug delivery efficacy and therapeutic ***,we constructed TRAIL-[NDHCPT]^(GAC),a synergistic hydroxycamptothecin(HCPT)and tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)protein co-loaded disk-shaped nanocarrier withγ-glutamyl transpeptidase *** the novel nanodisks extravasated into the tumor interstitium,theγ-glutamyl transpeptidase overexpressed on the tumor cell membranes cleaved theγ-glutamyl portions of the nanodisk surface to produce positively charged amino *** a result,the cationic nanodisks possessed stronger tumor infiltration ability through transcytosis than anionic *** and TRAIL exerted synergistic antitumor effects with better overall therapeutic *** TRAIL-[ND-HCPT]^(GAC)system performed significantly better than free HCPT and remarkably prolonged the survival of breast tumor-bearing mice with no significant toxicity.

关键词： tumor penetration combination therapy charge reversal γ-glutamyl transpeptidase nanodisk

Impact of Robinia pseudoacacia stand conversion on soil properties and bacterial community composition in Mount Tai,China

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Forest Ecosystems 2021年第2期8卷 253-264页

作者： Kun Li Xu Han Ruiqiang Ni Ge Shi Sergio de-Miguel Chuanrong Li Weixing Shen yikun Zhang Xingzhong Zhang Mountain Tai Forest Ecosystem Research Station of State Forestry Administration/Key Laboratory of State Forestry Administration for Silviculture of the Lower Yellow River Tai’an 271018ShandongChina Department of Crop and Forest Sciences University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC–AGROTECNIO Av.Alcalde Rovira Roure 191E25198 LleidaSpain Mount Tai Scenic Spot Management Committee Tai’an 271000 ShandongChina

Background:Robinia pseudoacacia is a widely planted pioneer tree species in reforestations on barren mountains in northern *** of its nitrogen-fixing ability,it can play a positive role in soil and forest *** clearcutting of planted stands,*** stands become coppice *** impacts of shifting from seedling to coppice stands on soil bacterial community and soil properties have not been wel *** study aims to quantify how soil properties and bacterial community composition vary between planted seedling versus coppice ***:Nine 20 m×20 m plots were randomly selected in seedling and coppice *** bulk soil and rhizosphere soil were sampled in summer *** soil was sampled at 10 cm from the soil surface using a soil *** soil samples were col ected using a *** soil samples were transported to the laboratory for chemical analysis,and bacterial community composition and diversity was obtained through DNA extraction,16 S r RNA gene amplification and high-throughput ***:The results showed that,compared to seedling plantations,soil quality decreased significantly in coppice stands,but without affecting soil exchangeable Mg^(2+) and K^(+).Total carbon(C)and nitrogen(N)were lower in the rhizosphere than in bulk soil,whereas nutrient availability showed an opposite *** conversion from seedling to coppice plantations was also related to significant differences in soil bacterial community structure and to the reduction of soil bacterialα-*** component analysis(PCA)showed that bacterial community composition was similar in both bulk and rhizosphere soils in second-generation coppice *** y,the conversion from seedling to coppice stands increased the relative abundance of Proteobacteria and Rhizobium,but reduced that of Actinobacteria,which may result in a decline of soil nutrient *** tests revealed that C,N,soil organic matte

关键词： Black locust coppice plantation Forest restoration Afforestation Microbial structure Soil nutrient Soil quality

Basal defense is enhanced in a wheat cultivar resistant to Fusarium head blight

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Journal of Integrative Agriculture 2024年第4期23卷 1238-1258页

作者： Xinlong Gao Fan Li yikun Sun Jiaqi Jiang Xiaolin Tian Qingwen Li Kaili Duan Jie Lin Huiquan Liu Qinhu Wang State Key Laboratory for Crop Stress Resistance and High-Efficiency Production College of Plant ProtectionNorthwest A&F UniversityYangling 712100China

Fusarium head blight(FHB),mainly caused by the fungal pathogen Fusarium graminearum,is one of the most destructive wheat *** directly affecting the yield,the mycotoxin residing in the kernel greatly threatens the health of humans and *** 979(XN979)is a widely cultivated wheat elite with high yield and FHB ***,its resistance mechanism remains *** this study,we studied the expression of genes involved in plant defense in XN979 by comparative *** found that the FHB resistance in XN979 consists of two lines of *** first line of defense,which is constitutive,is knitted via the enhanced basal expression of lignin and jasmonic acid(JA)biosynthesis *** second line of defense,which is induced upon *** infection,is contributed by the limited suppression of photosynthesis and the struggle of biotic stress-responding ***,the effective defense in XN979 leads to an inhibition of fungal gene expression,especially in the early infection *** formation of the FHB resistance in XN979 may coincide with the breeding strategies,such as selecting high grain yield and lodging resistance *** study will facilitate our understanding of *** interaction and is insightful for breeding FHB-resistant wheat.

关键词： Fusarium head blight Xinong 979 lignin jasmonic acid photosynthesis Fusarium graminearum

Preparation of FePt magnetic nanodot arrays by nanosphere lithography

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Chinese Science Bulletin 2007年第8期52卷 1125-1128页

作者： wu PeiWen FANG yikun TUO XinLin WANG XiaoGong HAN BaoShan YUAN Jun Laboratory of Advanced Materials Department of Materials Science and Engineering Tsinghua University Beijing 100084 China National Centre for Electron Microscopy (Beijing) Tsinghua University Beijing 100084 China State Key Laboratory of Magnetism Beijing National Laboratory for C0ndensed Physics Instiiute of Physics Chinese Academy of Sciences Beijing 100080 China Department oi Chemical Engineering Tsinghua University Beijing 100084 China

Magnetic FePt nanodot arrays are promising candidates for making quantum magnetic recording disk. Here we introduce a hybrid method of FePt nanodot array fabrication through nanosphere lithography. This method combines the advantages of both top-down and bottom-up approaches and does not re- quire expensive equipment nor complicated processing *** size of magnetic FePt nanodots prepared can be as small as 40 nm.

关键词： FePt磁性纳米点阵列制备纳米球平版印刷术

Combined chemo-endocrine therapy as a potential new option for HR+/HER2−advanced breast cancer:a prospective study of fulvestrant plus oral vinorelbine

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Cancer Biology & Medicine 2023年第4期20卷 287-296页

作者： Xue Wang Jian Yue yikun Kang Zhong Dai Jie Ju Jiayu Wang Pin Zhang Fei Ma Binghe Xu Peng Yuan Department of VIP Medical Services National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Medical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Comprehensive Oncology Huanxing Cancer HospitalBeijing 100026China Department of Medical Oncology and Clinical Trial Center National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

Objective:Endocrine therapy with fulvestrant has shown synergistic antitumor effects with some chemotherapy drugs in *** study evaluated the efficacy and safety of fulvestrant with vinorelbine in patients with hormone receptor positive(HR+)/human epidermal growth factor receptor-2-negative(HER2−)recurrent or metastatic breast ***:Patients were intramuscularly administered fulvestrant 500 mg(day 1 per cycle for 28 days)and oral vinorelbine(60 mg/m2 on days 1,8,and 15 of each cycle).The primary endpoint was progression-free survival(PFS).Secondary endpoints included overall survival,objective response rate,disease control rate,duration of response,and ***:A total of 38 patients with HR+/HER2−advanced breast cancer included in the study were followed up for a median time of 25.1 *** overall median PFS was 9.86 months[95%confidence interval(CI)7.2-23.13],and the median PFS of the first-line and the second-line treatment population was 20.73 months(95%CI 9.82 to NR)and 4.27 months(95%CI 3.68 to NR),*** adverse events reported were of grade 1/2,and none were of grade 4/***:This is the first exploratory study of a fulvestrant and oral vinorelbine regimen in the treatment of HR+/HER2−recurrent and metastatic breast *** combination chemo-endocrine therapy was efficacious,safe,and promising for patients with HR+/HER2−advanced breast cancer.

关键词： HR+/HER2−breast cancer recurrence metastasis fulvestrant oral vinorelbine