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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2024年

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di man-cheng tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase SpeF and P450 monooxygenase SpeG, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, SpeF/SpeG metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-mA with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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Ensemble projections of climate and streamflow in a typical basin of semi-arid steppes in Mongolian Plateau of 2021-2100

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Advances in Climate Change Research 2024年第2期15卷 230-243页

作者： Hang PAN Jian-Ping tang Liang cheng man-Chun LI Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Nanjing UniversityNanjing 210023China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing UniversityNanjing 210023China School of Atmospheric Sciences Nanjing UniversityNanjing 210023China

The Kherlen River is the main water source for Hulun Lake,the largest lake in northern *** to reduced inflow from the Kherlen River,Hulun Lake experienced rapid shrinkage at the beginning of the 21st century,posing a serious threat to the ecological security of northern ***,there is still a significant lack of projections regarding future climate change and its hydrological response in the Kherlen River *** study analyzed the projected climate and streamflow changes in the Kherlen River basin,a vital yet vulnerable international semi-arid steppes type basin.A combination of multi-model ensemble projection techniques,and the soil and water assessment tool(SWAT)model was employed to examine the spatio-temporal changes in precipitation,temperature,streamflow,and the associated uncertainties in the *** temperature(an increase of 1.84-6.42℃)and the precipitation(an increase of 15.0-46.0 mm)of Kherlen River basin are projected to increase by 2100,leading to a rise in streamflow(1.08-4.78 m^(3) s^(-1)).The upstream of the Kherlen River exhibits remarkable increasing trends in precipitation,which has a dominant influence on streamflow of Kherlen *** increases in streamflow are observed in April,August,September,and October compared to the reference period(1971-2000).These findings suggest a partial alleviation of water scarcity in the Kherlen River,but also an increased likelihood of hydrological extreme *** projected temperature increase in the Kherlen River basin exhibits the smallest uncertainty,while more pronounced uncertainties are found in precipitation and *** spread among the results of CMIP6 models is greater than that of CMIP5 models,with lower signal-to-noise ratio(SNR)values for temperature,precipitation,and streamflow.

关键词： Climate change Flow projection Uncertainty SWAT Mongolian Plateau

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Aryl C–H iodination: are there actual flavin-dependent iodinases in nature?

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Science China Chemistry 2021年第10期64卷 1730-1735页

作者： Yuyang Zhang Lin Chen Hongping Chen Tingting Huang Qing Shi Xiaozheng Wang Yan Wang man-cheng tang Ning-Yi Zhou Shuangjun Lin Synthetic Biology Engineering Lab of Henan Province School of Life Science and BiotechnologyXinxiang Medical UniversityXinxiang 453003China State Key Laboratory of Microbial Metabolism Joint International Laboratory on Metabolic&Developmental SciencesSchool of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China

Flavin-dependent halogenases (FDHs) are well known to introduce carbon halide bonds (mainly C–Cl and C–Br) into natural products with the assistance of a partner protein flavin reductase to generate reduced flavin (FADH_(2)or FMNH_(2)).Compared with the common chloride-and bromide-containing natural products (approximately 5,000 compounds),iodinated natural products(approximately 100 compounds) are very *** iodinases have also rarely been identified in nature to *** study discovered a novel relationship between iodination and flavin reductases for the first *** mechanistic studies,it was identified that peroxide (H_(2)O_(2)) was released from the uncoupling reaction of flavin reductases and then reacted with iodide ions(I^(-)) to produce hypoiodous acid (IOH) for the final ***,this study also unintentionally verified that the recently reported flavin-dependent iodinase Vir X1 from the marine virus and its two homologs (MBG and NCV) did not catalyze iodination in the in vitro biochemical system but likely belonged to a new phylogenetic clade in the tryptophan halogenase *** a consequence,actual flavin-dependent iodinases in nature remain to be discovered by the scientific community in the future.

关键词： flavin-dependent halogenase flavin reductase iodination H_(2)O_(2) iodinase

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Flame-retardant ammonium polyphosphate/MXene decorated carbon foam materials as polysulfide traps for fire-safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第2期89卷 313-323,I0008页

作者： Yang Li Yong-cheng Zhu Sowjanya Vallem man Li Seunghyun Song Tao Chen Long-cheng tang Joonho Bae Department of Physics Gachon UniversitySeongnam-siGyeonggi-do 13120South Korea Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education College of MaterialChemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou 311121ZhejiangChina Key laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China School of Materials Engineering Changzhou Vocational Institute of Industry TechnologyChangzhou 213164JiangsuChina

Lithium-sulfur(Li-S)batteries are one of the most promising modern-day energy supply systems because of their high theoretical energy density and low ***,the development of high-energy density Li-S batteries with high loading of flammable sulfur faces the challenges of electrochemical performance degradation owing to the shuttle effect and safety issues related to fire or explosion *** this work,we report a three-dimensional(3D)conductive nitrogen-doped carbon foam supported electrostatic self-assembled MXene-ammonium polyphosphate(NCF-MXene-APP)layer as a heat-resistant,thermally-insulated,flame-retardant,and freestanding host for Li-S batteries with a facile and costeffective synthesis ***,through the use of NCF-MXene-APP hosts that strongly anchor polysulfides,the Li-S batteries demonstrate outstanding electrochemical properties,including a high initial discharge capacity of 1191.6 mA h g^(-1),excellent rate capacity of 755.0 mA h g^(-1)at 1 C,and long-term cycling stability with an extremely low-capacity decay rate of 0.12%per cycle at 2 *** importantly,these batteries can continue to operate reliably under high temperature or flame attack ***,this study provides valuable insights into the design of safe high-performance Li-S batteries.

关键词： Flame-retardant MXene Ammonium polyphosphate Safety Lithium-sulfur battery

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Safety and effectiveness of butorphanol in epidural labor analgesia:A protocol for a systematic review and meta-analysis

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World Journal of Clinical Cases 2024年第8期12卷 1416-1421页

作者： Guan-cheng tang man He Zhen-Zhao Huang Yan cheng Department of Anesthesiology Yongkang Hospital of Traditional Chinese MedicineJinhua 321301Zhejiang ProvinceChina Department of Gynecology and Obstetrics Yongkang Hospital of Traditional Chinese MedicineJinhua 321301Zhejiang ProvinceChina Department of Anesthesiology Hangzhou United Liger Sixth Medical Beauty HospitalHangzhou 311215Zhejiang ProvinceChina Department of Ultrasound Hangzhou Women’s HospitalHangzhou 310008Zhejiang ProvinceChina

BACKGROUND Epidural analgesia is the most effective analgesic method during *** administered epidurally has been shown to be a successful analgesic method during ***,no comprehensive study has examined the safety and efficacy of using butorphanol as an epidural analgesic during *** To assess butorphanol's safety and efficacy for epidural labor *** The PubMed,Cochrane Library,EMBASE,Web of Science,China National Knowledge Infrastructure,and Google Scholar databases will be searched from *** types of literature,such as conference abstracts and references to pertinent reviews,will also be *** will include randomized controlled trials comparing butorphanol with other opioids combined with local anesthetics for epidural analgesia during *** will be no language *** primary outcomes will include the visual analog scale score for the first stage of labor,fetal effects,and Apgar *** independent reviewers will evaluate the full texts,extract data,and assess the risk of *** bias will be evaluated using Egger's or Begg's tests as well as visual analysis of a funnel plot,and heterogeneity will be evaluated using the Cochran Q test,P values,and I2 ***-analysis,subgroup analysis,and sensitivity analysis will be performed using Revman software version *** protocol was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)Protocols statement,and the PRISMA statement will be used for the systematic *** This study provides reliable information regarding the safety and efficacy of using butorphanol as an epidural analgesic during *** To support clinical practice and development,this study provides evidence-based findings regarding the safety and efficacy of using butorphanol as an epidural analgesic during labor.

关键词： Epidural analgesia during labor Butorphanol Safety Protocol Meta-analysis

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Effect of succinic acid on morphology transformation of the anhydrous magnesium carbonate particles prepared by magnesium chloride hexahydrate and urea

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Particuology 2024年第7期90卷 209-217页

作者： Song Liu Guojun cheng Zhongfeng tang School of Materials Science and Engineering Anhui University of Science and TechnologyHuainan232001China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Anhui Province Key Laboratory of Environment-friendly Polymer Materials Anhui UniversityHefei230601China

The homogeneous and controllable morphology of anhydrous magnesium carbonate(MgCO_(3))particles with excellent properties is difficult to obtain because of a variety of synthetic *** effect of succinic acid as a crystal modifier on the particle morphology transformation of anhydrous MgCO_(3)was investigated by the hydrothermal *** effect of the addition of succinic acid on the particles was similar to that of temperature *** morphology of particles with a folded diamond-like shape was gradually uniform,and the particle size was between 3.3 and 7.5μ*** MgCO_(3)particles prepared at pH 9 could easily agglomerate,and the average particle size increased from diamond-like to cube-like as the reaction time *** interaction between succinic acid and magnesium ions at different concentrations was the main factor responsible for the morphological *** pH,temperature,and time affected the molecular motion rate and crystal growth.

关键词： MgCO_(3) MgCl_(2)·6H_(2)O Urea Succinic acid Morphology

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Highlights in recent wireless power IC research

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Journal of Semiconductors 2024年第4期45卷 5-7页

作者： cheng Huang Junyao tang Iowa State University AmesIowa50011USA

Wireless power transfer(WPT)has been a popular topic in power integrated circuit(IC)designs in the past *** slogan"cutting the last wire"presented in ISSCC’15[1],WPT is poised to take over many wired power deliveries applica-tions today,just like what happened to wireless communica-tion *** the years,WPT has become more mature and more wirelessly charged or powered products have become available on the *** mini review intends to summarize recent breakthroughs in WPT inte-grated circuits(IC)research.

关键词： WPT power wireless

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Model-driven path planning for robotic plasma cutting of branch pipe with single Y-groove based on pipe-rotating scheme

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Advances in manufacturing 2024年第1期12卷 94-107页

作者： Yan Liu Qiu tang Xin-cheng Tian School of Control Science and Engineering Shandong UniversityJinan250061People’s Republic of China Engineering Research Center of Intelligent Unmanned System Ministry of EducationJinan250061People’s Republic of China School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan250101People’s Republic of China

The automatic cutting of intersecting pipes is a challenging task in *** improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single ***,it summarizes the intersection forms and introduces a dual-pipe intersection *** on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is ***,a novel mathematical model for plasma radius and taper compensation is ***,the compensation model and groove model are integrated by establishing movable ***,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is *** the established models and moving frames,the planned path description of cutting robot is provided in this novel *** accuracy of the proposed method is verified by simulations and robotic cutting experiments.

关键词： Automatic groove cutting of intersecting pipes Model-driven robot path planning Plasma beam radius and taper compensation

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Capillary Property of Entangled Porous Metallic Wire materials and Its Application in Fluid Buffers:Theoretical Analysis and Experimental Study

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Defence Technology（防务技术） 2024年第1期31卷 400-416页

作者： Yu tang Yiwan Wu Hu cheng Rong Liu Engineering Research Center for Metal Rubber School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350156China AECC Guizhou Liyang Aviation Power Co. LTDGuiyang 550014China College of Computer and Information Sciences Fujian Agriculture and Forestry UniversityFuzhou 350156China

Strong impact does serious harm to the military industries so it is necessary to choose reasonable cushioning material and design effective buffers to prevent the impact of *** on the capillary property entangled porous metallic wire materials(EPMWM),this paper designed a composite buffer which uses EPMWM and viscous fluid as cushioning materials under the low-speed impact of the recoil force device of weapon equipment(such as artillery,mortar,etc.).Combined with the capillary model,porosity,hydraulic diameter,maximum pore diameter and pore distribution were used to characterize the pore structure characteristics of *** calculation model of the damping force of the composite buffer was *** low-speed impact test of the composite buffer was *** parameters of the buffer under low-speed impact were identified according to the model,and the nonlinear model of damping force was *** test results show that the composite buffer with EPMWM and viscous fluid can absorb the impact energy from the recoil movement effectively,and provide a new method for the buffer design of weapon equipment(such as artillery,mortar,etc.).

关键词： Entangled porous metallic wire materials Capillary property Viscousfluid Low-speed impact Damping force

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Spreadsheet quality assurance:a literature review

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Frontiers of Computer Science 2024年第2期18卷 61-82页

作者： Pak-Lok POON man Fai LAU Yuen Tak YU Sau-Fun tang School of Engineering and Technology Central Queensland UniversityMelbourne 3000Australia Department of Computing Technologies Swinburne University of TechnologyHawthorn 3122Australia Department of Computer Science City University of Hong KongHong Kong SAR 999077China The Royal Victorian Eye and Ear Hospital East Melbourne 3002Australia

Spreadsheets are very common for information processing to support decision making by both professional developers and non-technical end ***,business intelligence and artificial intelligence are increasingly popular in the industry nowadays,where spreadsheets have been used as,or integrated into,intelligent or expert systems in various application ***,it has been repeatedly reported that faults often exist in operational spreadsheets,which could severely compromise the quality of conclusions and decisions based on the *** a view to systematically examining this problem via survey of existing work,we have conducted a comprehensive literature review on the quality issues and related techniques of spreadsheets over a 35.5-year period(from January 1987 to June 2022)for target journals and a 10.5-year period(from January 2012 to June 2022)for target *** other findings,two major ones are:(a)Spreadsheet quality is best addressed throughout the whole spreadsheet life cycle,rather than just focusing on a few specific stages of the life cycle.(b)Relatively more studies focus on spreadsheet testing and debugging(related to fault detection and removal)when compared with spreadsheet specification,modeling,and design(related to development).As prevention is better than cure,more research should be performed on the early stages of the spreadsheet life *** by our comprehensive review,we have identified the major research gaps as well as highlighted key research directions for future work in the area.

关键词： decision support system end-user computing end-user programming Excel spreadsheet

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