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Science China Chemistry 2025年

作者： qianqian chen Haoxing Xu Bingyue Zhao Yeersen Patehebieke Zerun Zhao Xiao Wang School of Chemistry and Chemical Engineering Nanjing University Frontiers Science Center for Critical Earth Material Cycling Nanjing University

The selective nucleoside synthesis through direct condensation between nucleobase and unactivated sugar in aqueous media has long been a formidable obstacle for the early chemical transformations hypothesized to construct the RNAWorld, due to product complexity and the low selectivity of the desired isomer. The preference of β-furanoside, the extant RNA component, has never been documented. Here we report an aqueous ribosylation mediated by divalent transition-metal ions, which unprecedentedly enhances the selectivity of furanosyl ribonucleosides as opposed to the traditionally predominating pyranosyl ones, with the furanoside/pyranoside ratio reaching up to 9/1. Furthermore, β-furanoside stands out for the first time as the most prevalent isomer in the presence of zinc and ammonium salts. The mechanism of this selectivity is elucidated with density functional theory calculations. The selectivity for β-furanoside can be further elevated via the adsorption on a zinc mineral. These findings exhibit as the first example that the selection of nucleosides with the desired, canonical configuration might be completed in the early stage of the RNA-forming process as opposed to later evolution, promoted by simple and widespread transition-metal minerals. The study may also find its value in synthetic chemistry as a guideline for developing a sustainable and selective glycosylation process.

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中央环保督察下地方环境治理逻辑及路径续造

黑龙江环境通报 2025年第1期38卷 146-148页

作者：陈千千湘潭大学公共管理学院湖南湘潭411105

中央生态环保督察是我国环保工作中的创新之举,为国家生态环境的改善发挥了重要的作用。地方政府环境治理策略的选择遵从“发展论”和“还原论”为原则的提升定向型和预防定向型环境治理逻辑,仍需从明确“以人为本”的环境治理价值目标... 详细信息

中央生态环保督察是我国环保工作中的创新之举,为国家生态环境的改善发挥了重要的作用。地方政府环境治理策略的选择遵从“发展论”和“还原论”为原则的提升定向型和预防定向型环境治理逻辑,仍需从明确“以人为本”的环境治理价值目标、创新环境治理制度设计与技术、形成互动交流的环境治理文化、加强公众参与和社会监督、强化环境监测和信息公开等方面来实现地方生态环境可持续发展。

关键词：中央环保督察地方环境治理行为逻辑

Scalping or Line-sitting:The Role of Speculators

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Journal of Systems Science and Systems Engineering 2022年第1期31卷 1-33页

作者： qianqian chen Zhenyang Shi Yi Yang School of Management Zhejiang UniversityHangzhou310058China

Speculative behaviors have burgeoned in various business settings whereby it is costly for consumers to purchase directly from *** paper examines the values of two typical speculative behaviors,scalping and line-sitting,against a backdrop of markets with *** establish a two-stage model in which a monopolist seller sells an item(product or service)to consumers in the first stage,and the item can be traded on a resale platform in the second *** have no interests in consumption but incur lower costs in pm-chasing and reselling processes than *** the scalping model,they buy the item first and resell it later to make *** the line-sitting model,they earn incomes by serving as surrogates of consumers in *** first find whether the two phenomena emerge critically depends on the value of consumers'entry *** main results indicate that both speculative behaviors can bring benefits to the seller and resale platform by a demand expansion effect,although through different *** scalping,the entry of speculators as additional buyers always boosts demand in both stages,and achieves a win-win outcome for the seller and platform,although less consumers remain in the market and the resale price *** line-sitting,demand is enlarged and profits rise in both stages,only when consumers find purchasing directly more time-and money-consuming,because they need to pay an extra service fee to ***,the consumer population gets better off from the two speculative behaviors when their entry cost is relatively *** both models emerge,scalping may be preferable to line-sitting for the seller,resale platform and consumers,if the cost advantage of speculators in resale transactions is more evident.

关键词： Speculative behavior scalping line-sitting strategic behavior entry cost

Enhancing corrosion resistance of plasma electrolytic oxidation coatings on AM50 Mg alloy by inhibitor containing Ba(NO_(3))_(2) solutions

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2048-2061页

作者： Jirui Ma Xiaopeng Lu Santosh Prasad Sah qianqian chen You Zhang Fuhui Wang Corrosion and Protection Center Northeastern UniversityShenyang110819China Faculty of Engineering Hokkaido UniversityHokkaido 060-8628Japan College of New Materials and Chemical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China

To enhance the long-term corrosion resistance of the plasma electrolytic oxidation(PEO)coating on the magnesium(Mg)alloy,an inorganic salt combined with corrosion inhibitors was used for posttreatment of the *** this study,the corrosion performance of PEO-coated AM50 Mg was significantly improved by loading sodium lauryl sulfonate(SDS)and sodium dodecyl benzene sulf-onate into Ba(NO_(3))_(2) post-sealing *** electron microscopy,X-ray photoelectron spectroscopy,X-ray diffraction,Fourier transform infrared spectrometer,and ultraviolet-visible analyses showed that the inhibitors enhanced the incorporation of BaO_(2) into PEO *** impedance showed that post-sealing in Ba(NO_(3))_(2)/SDS treatment enhanced corrosion resistance by three orders of *** total impedance value remained at 926Ω·cm^(2)after immersing in a 0.5wt%NaCl solution for 768 h.A salt spray test for 40 days did not show any obvious region of corrosion,proving excellent post-sealing by Ba(NO_(3))_(2)/SDS *** corrosion resistance of the coating was enhanced through the synergistic effect of BaO2 pore sealing and SDS adsorption.

关键词： Mg plasma electrolytic oxidation posttreatment corrosion resistance

Effect of three tongue needles acupoints Lianquan(CV23) and Hegu(LI4) combined with swallowing training on the quality of life of laryngeal cancer patients with dysphagia after surgery

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Journal of Traditional Chinese Medicine 2022年第4期42卷 617-621页

作者： ZHU Xuewei LIU Minghui ZONG Minru chen qianqian WANG Jianfeng Department of otolaryngology head and neck surgery China-Japan Union Hospital of Jilin UniversityChangchun 130033China Department of Chinese traditional Medicine China-Japan Union Hospital of Jilin UniversityChangchun 130033China Department of rehabilitation China-Japan Union Hospital of Jilin UniversityChangchun 130033China Department of Radiotherapy China-Japan Union Hospital of Jilin UniversityChangchun 130033China

OBJECTIVE:To evaluate the effect of acupuncture therapies administered in combination with swallowing training on the quality of life of laryngeal cancer patients with dysphagia after ***:Seventy-one postoperative patients with laryngeal cancer participated in this *** patients diagnosed with swallowing dysfunction by video fluoroscopic swallowing examination(VFSE)were randomly divided into experimental group(n=36)and control group(n=35).Patients in both groups were provided swallowing training and rehabilitation *** in the experimental group were additionally provided with acupuncture *** patients were evaluated using VFSE and MD Anderson dysphagia inventory(MDADI)and Quality of Life Questionnaire-core 30(QLQ-c30)score immediately after surgery and three months ***:The effective rate of 97.1%(n=35)and the complete remission rate of 36.1%(n=13)in the experimental group were higher than those in the control group of 60%(n=21)and 14.3%(n=5)(P<0.01).The scores of VFSE,MDADI and QLQ-c 30 in the experimental group and the control group at three months after therapies were significantly improved compared with those before therapies(P<0.05).The scores of VFSE,MDADI and QLQ-c30 in the experimental group at three months after therapies were significantly improved compared with the control *** improvement in the intervention group was significantly better than that in the control *** were no adverse reactions in two ***:Acupuncture therapies combined with swallowing training can improve the swallowing function and the quality of life of laryngeal cancer patients with dysphagia after surgery.

关键词： laryngeal neoplasms deglutition disorders acupuncture swallowing training quality of life

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A fluorescent Eu(Ⅲ) MOF for highly selective and sensitive sensing of picric acid

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Science China Chemistry 2019年第2期62卷 205-211页

作者： qianqian chen Jiahui cheng Jin Wang Liang Li Zhipeng Liu Xinhui Zhou Yujian You Wei Huang Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) Nanjing University of Posts & Telecommunications School of Telecommunication and Information Engineering Nanjing University of Posts & Telecommunications Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM) Jiangsu National Synergetic Innovation Center forAdvanced Materials (SICAM) Nanjing Tech University (Nanjing Tech) Shaanxi Institute of Flexible Electronics (SIFE) Northwestern Polytechnical University (NPU)

A metal-organic framework [Eu_3L_3(CH_3COO)_2(H_2O)_2(μ_3-OH)]·3 DMF,(EuL, H_2L=9H-carbazole-2,7-dicarboxylic acid,DMF=N,N-dimethylformamide) has been synthesized under solvothermal conditions and structurally characterized. In EuL,Eu_6O_8 clusters are four-bridged by carboxylates to form parallel-aligned Eu–O–C chains, which are further linked by the carbazole moieties of L^(2-) ligands to form the three-dimensional framework with rhombic channels. The EuL material with characteristic emission of Eu^(3+) ion exhibits significant luminescence quenching response for picric acid(PA) and the linear Stern-Volmer plot was observed in the concentration range of 0.05–0.15 mM with K_(sv) of 98074 M^(-1). As far as we know, this Ksv is among the highest values for COFs and MOFs in detection of PA. The excellent anti-interference ability and repeatability were also verified by experiments. Lastly, we investigated the luminescence quenching mechanism in the EuL sensing system.

关键词： europium metal-organic frameworks picric acid sensor

Plasma membrane calcium ATPase 4b inhibits nitric oxide generation through calcium-induced dynamic interaction with neuronal nitric oxide synthase

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Protein & Cell 2013年第4期4卷 286-298页

作者： Wenjuan Duan Juefei Zhou Wei Li Teng Zhou qianqian chen Fuyu Yang Taotao Wei National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Research Department of Bacterial Vaccine Chengdu Institute of Biological Products Co.LtdChengdu 610023China State Key Laboratory of Virology Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

The activation and deactivation of Ca^(2+)- and calmodulindependent neuronal nitric oxide synthase (nNOS) in the central nervous system must be tightly controlled to prevent excessive nitric oxide (NO) generation. Considering plasma membrane calcium ATPase (PMCA) is a key deactivator of nNOS, the present investigation aims to determine the key events involved in nNOS deactivation of by PMCA in living cells to maintain its cellular context. Using time-resolved Förster resonance energy transfer (FRET), we determined the occurrence of Ca^(2+)-induced protein-protein interactions between plasma membrane calcium ATPase 4b (PMCA4b) and nNOS in living cells. PMCA activation significantly decreased the intracellular Ca 2+ concentrations ([Ca^(2+)]_(i)), which deactivates nNOS and slowdowns NO synthesis. Under the basal [Ca^(2+)]_(i) caused by PMCA activation, no protein-protein interactions were observed between PMCA4b and nNOS. Furthermore, both the PDZ domain of nNOS and the PDZ-binding motif of PMCA4b were essential for the protein-protein interaction. The involvement of lipid raft microdomains on the activity of PMCA4b and nNOS was also investigated. Unlike other PMCA isoforms, PMCA4 was relatively more concentrated in the raft fractions. Disruption of lipid rafts altered the intracellular localization of PMCA4b and affected the interaction between PMCA4b and nNOS, which suggest that the unique lipid raft distribution of PMCA4 may be responsible for its regulation of nNOS activity. In summary, lipid rafts may act as platforms for the PMCA4b regulation of nNOS activity and the transient tethering of nNOS to PMCA4b is responsible for rapid nNOS deactivation.

关键词： plasma membrane calcium ATPase neu-ronal nitric oxide synthase calcium nitric oxide lipid raft Förster resonance energy transfer

Uniform Formation of Amorphous Cobalt Phosphate on Carbon Nanotubes for Hydrogen Evolution Reaction

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Chinese Journal of Chemistry 2021年第8期39卷 2113-2118页

作者： Mengzhan Ge Xiaodong Zhang Shangzhou Xia Wenjie Luo Yuwei Jin qianqian chen Huagui Nie Zhi Yang Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhouZhejiang 325027China AECC Hunan Aviation Powerplant Research Institute ZhuzhouHunan 412002China

Tremendous efforts have been made to the development of highly active,stable hydrogen evolution reaction(HER)electrocatalysts based on earth-abundant metal ***,cobalt phosphorus(Co-P)catalysts have received particular... 详细信息

关键词： Cobalt phosphate Heteroge neous catalysis Carb on nano tubes Electrochemistry Water splitting

Chinese Dramas Prosper in the U.S

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China Today 2015年第1期64卷 72-74页

作者： chen qianqian UCLA

AS executive director of UCLA's Con- fucius Institute, Dr. Susan Pertel Jain is roficient in Mandarin and has studied hinese drama for many years. Through the Confucius Institute, she has devoted herself to researc... 详细信息

关键词： In Chinese Dramas Prosper in the U.S

Soybean(Glycine max)rhizosphere organic phosphorus recycling relies on acid phosphatase activity and specific phosphorusmineralizing-related bacteria in phosphate deficient acidic soils

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Journal of Integrative Agriculture 2024年第5期23卷 1685-1702页

作者： qianqian chen Qian Zhao Baoxing Xie Xing Lu Qi Guo Guoxuan Liu Ming Zhou Jihui Tian Weiguo Lu Kang chen Jiang Tian Cuiyue Liang Root Biology Center State Key Laboratory for Conservation and Utilization of Subtropical Agro-BioresourcesCollege of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China Henan Academy of Crops Molecular Breeding Henan Academy of Agricultural SciencesZhengzhou 450002China

Bacteria play critical roles in regulating soil phosphorus(P) cycling. The effects of interactions between crops and soil P-availability on bacterial communities and the feedback regulation of soil P cycling by the bacterial community modifications are poorly understood. Here, six soybean(Glycine max) genotypes with differences in P efficiency were cultivated in acidic soils with long-term sufficient or deficient P-fertilizer treatments. The acid phosphatase(AcP) activities, organic-P concentrations and associated bacterial community compositions were determined in bulk and rhizosphere soils. The results showed that both soybean plant P content and the soil AcP activity were negatively correlated with soil organic-P concentration in P-deficient acidic soils. Soil P-availability affected the ɑ-diversity of bacteria in both bulk and rhizosphere soils. However, soybean had a stronger effect on the bacterial community composition, as reflected by the similar biomarker bacteria in the rhizosphere soils in both P-treatments. The relative abundance of biomarker bacteria Proteobacteria was strongly correlated with soil organic-P concentration and AcP activity in low-P treatments. Further high-throughput sequencing of the phoC gene revealed an obvious shift in Proteobacteria groups between bulk soils and rhizosphere soils, which was emphasized by the higher relative abundances of Cupriavidus and Klebsiella, and lower relative abundance of Xanthomonas in rhizosphere soils. Among them, Cupriavidus was the dominant phoC bacterial genus, and it was negatively correlated with the soil organic-P concentration. These findings suggest that soybean growth relies on organic-P mineralization in P-deficient acidic soils, which might be partially achieved by recruiting specific phoCharboring bacteria, such as Cupriavidus.

关键词： organic phosphorus acid phosphatase soybean bacterial community phoC-harboring bacteria rhizosphere