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Total synthesis of a putative yuzurimine-type Daphniphyllum alkaloid C_(14)–epi-deoxycalyciphylline H

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Chinese Chemical Letters 2024年第4期35卷 336-339页

作者： jingping Hu jing xu Shenzhen Grubbs Institute and Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis Southern University of Science and TechnologyShenzhen 518055China

One of the largest subfamilies within the famous Daphniphyllum alkaloid family is made up of the yuzurimine-type(or macrodaphniphyllamine-type) alkaloids. Their complex aza-polycyclic caged structures, several contiguous stereogenic centers, and vicinal all-carbon quaternary centers make these alkaloids formidable challenge for synthetic chemists. Recently, synthesis of these alkaloids has received extensive attention from our community. Herein, we wish to report the total synthesis of C_(14)–epideoxycalyciphylline H, a putative member of yuzurimine-type alkaloid subfamily. Key transformations employed in our approach include an intramolecular Prins reaction and a Pd-catalyzed enyne cycloisomerization. In addition, synthesis of a daphnezomine L-type alkaloid, paxdaphnidine A, was also studied.

关键词： Total synthesis Daphniphyllum alkaloids Yuzurimine-type alkaloids Prins reaction Enyne cycloisomerization

Rupture of a giant jejunal mesenteric cystic lymphangioma misdiagnosed as ovarian torsion: A case report

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World Journal of Clinical Cases 2024年第4期12卷 847-852页

作者： jing xu Tie-Feng Lv Department of Hepatopathy Hangzhou Xixi HospitalHangzhou 310023Zhejiang ProvinceChina

BACKGROUND Cystic lymphangioma is a rare benign tumor that affects the lymphatic system.Mesenteric lymphangiomas in the small bowel are extremely uncommon.CASE SUMMARY We present a 21-year-old female patient who complained of abdominal pain.The diagnosis of ovarian torsion was suspected after abdominopelvic unenhanced computed tomography and ultrasound revealed a large cyst in contact with the bladder,ovary,and uterus.The patient underwent emergency laparotomy per-formed by gynecologists,but it was discovered that the cystic tumor originated from the jejunum.Gastrointestinal surgeons were then called in to perform a cystectomy.Pathological examination confirmed the diagnosis of cystic lymphangioma of the mesentery.The patient had an uneventful postoperative recovery.CONCLUSION Mesenteric lymphangiomas can cause abdominal pain,and imaging techniques can help determine their characteristics,location,and size.Complete surgical excision and pathological examination are considered the standard treatment and diagnostic method.

关键词： Rupture Jejunum Mesenteric cystic lymphangioma Ovarian torsion Surgical excision Pathological examination Case report

Enhanced bright green luminescence from GdOF:Ho^(3+) up-conversion phosphor via Yb^(3+) doping

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Journal of Rare Earths 2024年第2期42卷 263-269,I0002页

作者： Linjun Qin Yue Guo jing xu Lixi Wang Qitu Zhang College of Materials Science and Engineering Nanjing Tech UniversityNanjing211816China

In this paper,a series of GdOF-based green phosphors doped with Ho^(3+) and Yb^(3+) ions was prepared by a simple co-precipitation method.The crystal structure s and optical prope rties were investigated in detail.The intensity of the emission of GdOF:Yb^(3+),Ho^(3+) phosphors is enhanced by the effective energy transfer from Yb^(3+) to Ho^(3+),and the optimal luminescence is achieved with the Ho^(3+)doping amount of 0.1 mol%as well as Yb^(3+) doping amount of 5 mol%.Tunable UC emission of samples is achieved by adjusting the doping concentration of Ho^(3+) or Yb^(3+).The purity of the green UC emission is further improved by enhancing the excitation pumping power.In addition,logarithmic functions of green,red and nearinfrared radiation intensities were calculated versus logarithmic function of pump power for further study.A possible UC luminescence mechanism between Yb^(3+) and Ho^(3+) is discussed based on powerdependent UC luminescence spectrum and decay lifetimes.These results suggest that GdOF:Yb^(3+),Ho^(3+)phosphors with bright and high-purity green UC emission have potential applications in the fields of bioimaging,display and illumination.

关键词： Up-conversion GdOF Lanthanide ions Rare earths

Can the improvement of competitive adequacy and fairness reduce discriminatory M&A behavior?Evidence from the market access negative list pilot in China

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China Journal of Accounting Research 2024年第1期17卷 96-131页

作者： Xiongyuan Wang jing xu Shuai Wang School of Accounting Zhongnan University of Economics and LawWuhanChina Institute of Ecological Civilization School of EconomicsZhongnan University of Economics and LawWuhanChina Huawei Technology Co.Ltd ShenzhenChina

Corporate mergers and acquisitions(M&As)are subject to skewed logic due to excessive government regulation.China is progressively adopting the Market Access Negative List(MANL)pilot to transfer the power of resource allocation from the government to the market.Using the DID method,we examine the impact of relaxing market access regulation on firms’M&A behavior against China’s institutional background and the M&A events of listed companies from 2012 to 2019.The MANL significantly increases firms’M&A tendency and amount and strengthens the competitive adequacy and fairness of market-oriented M&A decisions.Post-M&A financial performance does not increase,but human capital productivity,innovation effectiveness and total factor productivity do,demonstrating the dynamic balance of profit and efficiency in M&As.

关键词： Transition economies Market access deregulation Market access negative list Mergers and acquisitions

Microbial-inspired self-healing of concrete cracks by sodium silicate-coated recycled concrete aggregates served as bacterial carrier

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 14-29页

作者： jing xu Xianzhi WANG Wu YAO Anna A.KULMINSKAYA Surendra P.SHAH Key Laboratory of Advanced Civil Engineering Materials(Ministry of Education) School of Materials Science and EngineeringTongji UniversityShanghai 201804China Petersburg Nuclear Physics Institute Named by B.P.Konstantinov of National Research Centre Kurchatov InstituteGatchina 188300Russia Center for Advanced Construction Materials University of Texas at ArlingtonArlingtonTX 76019USA

Microbially induced carbonate precipitation(MICP)is a promising technique for the autonomous healing of concrete cracks.In this study,the effect of pH on MICP was investigated.The results indicate that the MICP process was inhibited when the pH was higher than 11.Both vaterite and calcite were produced when the pH was8.Recycled concrete aggregates(RCA)coated with sodium silicate have been proposed as protective carriers for microbial healing agents.Although the presence of the coated RCA resulted in a loss of the splitting tension strength of the concrete,the loaded healing agents were highly efficient in self-healing cracks.Concrete incorporated with 20%RCA loaded with healing agents exhibited the best self-healing performance.When the initial crack widths were between 0.3 and 0.4 mm,the 7-d mean healing rate was approximately 90%.At 28 d,the crack area filling ratio was 86.4%,while its water tightness recovery ratio was 74.4%and 29.8%,respectively,for rapid and slow absorption.This study suggests that RCA coated with sodium silicate is an effective method for packaging microbial healing agents and has great potential for developing cost-effective self-healing concrete.

关键词： self-healing microbial-induced carbonate precipitation water uptake recycled concrete aggregate protective carrier

RebL1 is required for macronuclear structure stability and gametogenesis in Tetrahymena thermophila

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Marine Life Science & Technology 2024年第2期6卷 183-197页

作者： Huijuan Hao Yinjie Lian Chenhui Ren Sitong Yang Min Zhao Tao Bo jing xu Wei Wang Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of BiotechnologyShanxi UniversityTaiyuan 030006China School of Life Science Shanxi UniversityTaiyuan 030006China Shanxi Key Laboratory of Biotechnology Taiyuan 030006China

Histone modification and nucleosome assembly play important roles in chromatin-related processes.Histone chaperones form different complexes and coordinate histone transportation and assembly.Various histone chaperone complexes have been identified in different organisms.The ciliate protozoa(ciliates)have various chromatin structures and different nuclear morphology.However,histone chaperone components and functions of different subunits remain unclear in ciliates.Tet-rahymema thermophila contains a transcriptionally active macronucleus(MAC)and a transcriptionally inactive micronu-cleus(MIC)which exhibit multiple replication and various chromatin remodeling progresses during vegetative growth and sexual developmental stages.Here,we found histone chaperone RebL1 not only localized evenly in the transcriptionally active MAC but also dynamically changed in the MIC during vegetative growth and sexual developmental stages.REBL1 knockdown inhibited cellular proliferation.The macronuclear morphology became bigger in growing mutants.The abnormal macronuclear structure also occurred in the starvation stage.Furthermore,micronuclear meiosis was disturbed during sexual development,leading to a failure to generate new gametic nuclei.RebL1 potentially interacted with various factors involved in histone-modifying complexes and chromatin remodeling complexes in different developmental stages.REBL1 knockdown affected expression levels of the genes involved in chromatin organization and transcription.Taken together,RebL1 plays a vital role in maintaining macronuclear structure stability and gametogenesis in T.thermophila.

关键词： Gametogenesis Histone chaperone Macronuclear structure RebL1 Tetrahymena thermophilaIntroduction

Achieving high-performance sodium metal anodes: From structural design to reaction kinetic improvement

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Nano Research 2024年第3期17卷 1288-1312页

作者： jing xu Jianhao Yang Yashuang Qiu Yang Jin Tianyi Wang Bing Sun Guoxiu Wang Research Center of Grid Energy Storage and Battery Application School of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001China College of Chemistry and Chemical Engineering Yangzhou University Yangzhou 225009China Centre for Clean Energy Technology School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology SydneyUltimoNSW 2007Australia

Sodium metal is one of the ideal anodes for high-performance rechargeable batteries because of its high specific capacity(~1166 mAh·g^(-1)),low reduction potential(-2.71 V compared to standard hydrogen electrodes),and low cost.However,the unstable solid electrolyte interphase,uncontrolled dendrite growth,and inevitable volume expansion hinder the practical application of sodium metal anodes.At present,many strategies have been developed to achieve stable sodium metal anodes.Here,we systematically summarize the latest strategies adopted in interface engineering,current collector design,and the emerging methods to improve the reaction kinetics of sodium deposition processes.First,the strategies of constructing protective layers are reviewed,including inorganic,organic,and mixed protective layers through electrolyte additives or pretreatments.Then,the classification of metal-based,carbon-based,and composite porous frames is discussed,including their function in reducing local deposition current density and the effect of introducing sodiophilic sites.Third,the recent progress of alloys,nanoparticles,and single atoms in improving Na deposition kinetics is systematically reviewed.Finally,the future research direction and the prospect of high-performance sodium metal batteries are proposed.

关键词： sodium metal anodes interface engineering current collector design reaction kinetics sodium deposition processes

Building Feedback-Regulation System Through Atomic Design for Highly Active SO_(2)Sensing

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Nano-Micro Letters 2024年第7期16卷 343-357页

作者： Xin Jia Panzhe Qiao Xiaowu Wang Muyu Yan Yang Chen Bao-Li An Pengfei Hu Bo Lu jing xu Zhenggang xue Jiaqiang xu NEST Lab Department of ChemistryCollege of SciencesShanghai UniversityShanghai 200444People’s Republic of China Shanghai Synchrotron Radiation Facility Zhangjiang LabShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204People’s Republic of China School of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026People’s Republic of China Key Laboratory of Organic Compound Pollution Control Engineering(MOE) School of Environmental and Chemical EngineeringShanghai UniversityShanghai 200444People’s Republic of China Shanghai University Instrumental Analysis&Research Center of Shanghai UniversityShanghai 200444People’s Republic of China

Reasonably constructing an atomic interface is pronouncedly essential for surface-related gas-sensing reaction.Herein,we present an ingen-ious feedback-regulation system by changing the interactional mode between single Pt atoms and adjacent S species for high-efficiency SO_(2)sensing.We found that the single Pt sites on the MoS_(2)surface can induce easier volatiliza-tion of adjacent S species to activate the whole inert S plane.Reversely,the activated S species can provide a feedback role in tailoring the antibonding-orbital electronic occupancy state of Pt atoms,thus creating a combined system involving S vacancy-assisted single Pt sites(Pt-Vs)to synergistically improve the adsorption ability of SO_(2)gas molecules.Further-more,in situ Raman,ex situ X-ray photoelectron spectroscopy testing and density functional theory analysis demonstrate the intact feedback-regulation system can expand the electron transfer path from single Pt sites to whole Pt-MoS_(2)supports in SO_(2)gas atmosphere.Equipped with wireless-sensing modules,the final Pt1-MoS_(2)-def sensors array can further realize real-time monitoring of SO_(2)levels and cloud-data storage for plant growth.Such a fundamental understanding of the intrinsic link between atomic interface and sensing mechanism is thus expected to broaden the rational design of highly effective gas sensors.

关键词： Feedback-regulation system Atomic interface SO_(2)sensor Single-atom sensing mechanism Intelligent-sensing array

Two-dimensional silica enhanced solid polymer electrolyte for lithium metal batteries

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Particuology 2024年第2期85卷 146-154页

作者： Zhihong Luo Weiyong Li Chong Guo Ya Song Mingxia Zhou Yan Shi jing xu Long Li Bin Shi Quansheng Ouyang Jiao-jing Shao Guangmin Zhou School of Materials and Metallurgy Guizhou UniversityGuiyang550025China State Key Laboratory of Advanced Chemical Power Sources Zunyi563003China Graphene Materials Engineering Research Center of Guizhou Colleges and Universities Guiyang550025China Tsinghua-Berkeley Shenzhen Institute&Tsinghua Shenzhen International Graduate Schoo Tsinghua UniversityShenzhen518055China

Solid polymer electrolytes(SPEs)are promising substitutes for current flammable liquid electrolytes to achieve high-safety and high-energy-density lithium metal batteries.Polyethylene oxide(PEO)based solid polymer electrolytes have attracted increasing attention because of their excellent flexibility,manufacturability,light weight,and low-cost processing,while they often suffer from low ionic con-ductivity at room temperature,low lithium transference number and unsatisfactory interfacial resis-tance,which largely restrain their practical application.Herein,two-dimensional holey silica nanosheets(2D-HSN)as the fillers,together with LiNO_(3) as the electrolyte additive,are introduced in a PEO/poly(-vinylidene fiuoride-co-hexafluoropropylene)(PVDF-HFP)blended polymer matrix to obtain a SPE.The incorporation of HSN filler creates supplementary channels for lithium ion migration and lowers the crystallinity of the polymer,thereby facilitating the movement of lithium ions.The HSN-based SPE demonstrates higher ionic conductivity up to 3.7 x 10-4 S cm-1 at 30℃,larger Li+transference number close to 0.34,and more stable lithium plating/stripping than that without the fillers,and HSN can promote the formation of more stable solid electrolyte interphase(SEI)layer.The as-assembled LiFePO4||Li batteries deliver a high specific capacity of 159 mA h g-1 with the capacity retention of 95.5%after 200 cycles at 30℃,as well as superior rate performance and cycling stability compared to that using the blank SPE.

关键词： Vermiculite nanosheets Two-dimensional silica Solid polymer electrolytes FillersLithium metal batteries