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Identification and characterization of camptothecin tailoring enzymes in Nothapodytes tomentosa

Journal of Integrative Plant Biology 2024年第6期66卷 1158-1169页

作者： Yin Chen Jian-Ping Huang yong-jiang wang Meng-Ling Tu Junheng Li Bingyan Xu Guoqing Peng Jing Yang Sheng-Xiong Huang State Key Laboratory of Phytochemistry and Plant Resources in West China and Yunnan Key Laboratory of Natural Medicinal Chemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China

Camptothecin is a complex monoterpenoid indole alkaloid with remarkable antitumor *** that two C-10 modified camptothecin derivatives,topotecan and irinotecan,have been approved as potent anticancer agents,there is a critical need for methods to access other aromatic ringfunctionalized congeners(e.g.,C-9,C-10,etc.).However,contemporary methods for chemical oxidation are generally harsh and low-yielding when applied to the camptothecin scaffold,thereby limiting the development of modified *** herein,we have identified four tailoring enzymes responsible for C-9 modifications of camptothecin from Nothapodytes tomentosa,via metabolomic and transcriptomic *** consist of a cytochrome P450(Nt CPT9H)which catalyzes the regioselective oxidation of camptothecin to 9-hydroxycamptothecin,as well as two methyltransferases(Nt OMT1/2,converting 9-hydroxycamptothecin to 9-methoxycamptothecin),and a uridine diphosphate-glycosyltransferase(Nt UGT5,decorating 9-hydroxycamptothecin to9-β-D-glucosyloxycamptothecin).Importantly,the critical residues that contribute to the specific catalytic activity of Nt CPT9H have been elucidated through molecular docking and mutagenesis *** work provides a genetic basis for producing camptothecin derivatives through metabolic *** will hasten the discovery of novel C-9 modified camptothecin derivatives,with profound implications for pharmaceutical manufacture.

关键词： camptothecin biosynthesis enzymatic assay Nothapodytes tomentosa tailoring enzyme transcriptomic analysis

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Preparation and Characterization of Polymeric PVDF/PDDA Ultrathin Films

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稀有金属材料与工程 2006年第A3期35卷 550-551页

作者： Yun Ye Yadong jiang yong wang Zhiming Wu Guangzhong Xie School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China

A new method for the production of nanoscaled polymeric multilayer films of ferroelectric PVDF is *** ultrathin multilayer films of poly diallyldimethylammonium chloride (PDDA) and polyvinylidene fluoride (PVDF) have been prepared on fuzed quartz substrate by the layer-by-layer self-assembly (LbL-SA) *** PDDA/PVDF multilayer films with the thickness of 30 nm to 150 nm have been characterized by quartz crystal microbalance (QCM) and infrared spectra (IR) The QCM reveals that the alternant ultrathin films of PVDF and PDDA are well order *** electric property of the ultrathin PDDA/PVDF multilayer films at room temperature is *** results show that property of ultrathin films differed from that of the thick films.

关键词： ultrathin films PVDF PDDA LbL-SA

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Evolutionary Multi/Many-Objective Optimisation via Bilevel Decomposition

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1973-1986页

作者： Shouyong jiang Jinglei Guo yong wang Shengxiang Yang School of Automation Central South UniversityChangsha 410083China Department of Computing Science University of AberdeenAberdeen AB243FXUK School of Computer Science Central China Normal UniversityWuhan 430079China School of Computer Science and Informatics De Montfort UniversityLeicester LE19BHUK

Decomposition of a complex multi-objective optimisation problem(MOP)to multiple simple subMOPs,known as M2M for short,is an effective approach to multi-objective ***,M2M facilitates little communication/collaboration between subMOPs,which limits its use in complex optimisation *** paper extends the M2M framework to develop a unified algorithm for both multi-objective and manyobjective *** bilevel decomposition,an MOP is divided into multiple subMOPs at upper level,each of which is further divided into a number of single-objective subproblems at lower *** subMOPs are allowed to share some subproblems so that the knowledge gained from solving one subMOP can be transferred to another,and eventually to all the *** bilevel decomposition is readily combined with some new mating selection and population update strategies,leading to a high-performance algorithm that competes effectively against a number of state-of-the-arts studied in this paper for both multiand many-objective *** analysis and component analysis have been also carried out to further justify the proposed algorithm.

关键词： Bilevel decomposition evolutionary algorithm many-objective optimisation multi-objective optimisation

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Developing Core-Shell Nano-Structures in FeCrAl-ODS Ferritic Alloys with the Co-Addition of Ni and Zr

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 364-372页

作者： Wenquan Ding Jieli Ma yong jiang Yiren wang Huiqun Liu Key Laboratory for Nonferrous Materials of Ministry of Education School of Materials Science and EngineeringCentral South UniversityChangsha410083China National Key Laboratory for Powder Metallurgy Central South UniversityChangsha410083China

A new Ni+Zr co-alloyed FeCrAl-ODS(oxide-dispersion-strengthened)ferritic alloy was fabricated by ball-milling and *** electron microscopy and atom probe tomography,the dispersive formation of high density core-shelled nano-particles of various sizes was confirmed with a common B2-NiAl *** which,median-sized nano-particles(20-50 nm)typically have an Y_(4)Al_(2)O_(9)nano-core of<~20 nm,ultra-fine nano-particles(<~20)nm have an Y_(4)Zr_(3)O_(12)nano-core of<~10 nm,and larger-sized nano-particles(50-100 nm)incorporate an ultra-fine Y_(4)Al_(2)O_(9)nano-core and a few ultra-fine Y_(4)Zr_(3)O_(12)*** these nano-phases were highly coherent with the ferritic *** large Y--Al-O nano-oxides were *** total number density of ultra-fine nano-particles was estimated as~2×10^(23)m^(-3)with a mean size of 6.3 nm only,and accordingly,the new alloy achieved an excellent combination of strength and ductility at high temperatures.

关键词： FeCrAl Oxide-dispersion-strengthened(ODS)alloy Mechanical alloying Nano-oxides Core-shell

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Mechanical Modeling and Analysis of Stability Deterioration of Production Well During Marine Hydrate Depressurization Production

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China Ocean Engineering 2024年第2期38卷 338-351页

作者： SUN Huan-zhao CHANG Yuan-jiang SUN Bao-jiang wang Kang CHEN Guo-ming LI Hao DAI yong-guo Centre for Offshore Engineering and Safety Technology China University of Petroleum(East China)Qingdao 266580China School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China jiangsu Shuguang Oil Tools Co. LtdTaizhou 225532China

Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate ***,the formations will undergo significant subsidence during depressurization,which will destroy the original force state of the production ***,existing research on the stability of oil and gas production wells assumes the formation to be stable,and lacks consideration of the force exerted on the hydrate production well by formation subsidence caused by hydrate decomposition during *** fill this gap,this paper proposes an analytical method for the dynamic evolution of the stability of hydrate production well considering the effects of hydrate *** on the mechanical model of the production well,the basis for stability analysis has been proposed.A multi-field coupling model of the force state of the production well considering the effect of hydrate decomposition and formation subsidence is established,and a solver is *** analytical approach is verified by its good agreement with the results from the numerical method.A case study found that the decomposition of hydrate will increase the pulling-down force and reduce the supporting force,which is the main reason for the stability *** higher the initial hydrate saturation,the larger the reservoir thickness,and the lower the production pressure,the worse the stability or even *** work can provide a theoretical reference for the stability maintaining of the production well.

关键词： natural gas hydrate production well depressurization production formation deformation stability deterioration

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Feedback processing in the primate brain and in AI systems

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Science China(Technological Sciences) 2024年第8期67卷 2297-2309页

作者： jiang yong HE Sheng Institute of Biophysics Chinese Academy of SciencesBeijing 100101China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China University of Chinese Academy of Sciences Beijing 100049China

The primate brain and artificial intelligence(AI) can both be conceptualized as information processing systems, each with its own distinct biological and computational architectures. While there are parallels between them, their respective structural and functional connections show significant differences. In this paper, we examine the central role of feedback processing in both the primate brain and AI systems, which has been shown to be crucial in shaping neural processing. By reviewing the key features of feedback processes in the primate brain, which allows the brain to incorporate prior knowledge, contextual information, and taskdemands into early-stage processing, we highlight the divergence in goals and functions between biological and AI *** these differences is crucial for elucidating the cognitive capabilities of the primate brain and for addressing computational challenges in AI. In advocating “Cognition-Inspired-Computation”, we suggest that integrating insights from feedback processing in the primate brain into AI research will offer potentially significant improvements for the advancement of AI systems.

关键词： cognitive neuroscience artificial intelligence feedback processing attention learning

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Advances in chemistry and bioactivity of the genus Erythroxylum

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Natural Products and Bioprospecting 2022年第1期12卷 179-198页

作者： Yulian Lv Tian Tian yong-jiang wang Jian-Ping Huang Sheng-Xiong Huang State Key Laboratory of Phytochemistry and Plant Resources in West China CAS Center for Excellence in Molecular Plant SciencesKunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Southwestern Chinese Medicine Resources Innovative Institute of Chinese Medicine and PharmacyChengdu University of Traditional Chinese MedicineChengdu 611137China

Erythroxylum *** is the largest and most representative genus of Erythroxylaceae *** contains approxi-mately 230 species that are mainly distributed in tropical and subtropical *** species in this genus,such as *** and ***,have been used as folk medicines in India or South America for a long *** is well known that Erythroxylum plants are rich in tropane alkaloids,and the representative member cocaine shows remarka-ble activity in human central nervous ***,many other types of active compounds have also been found in Erythroxylum along with the broadening and deepening of phytochemical *** date,a total of 383 com-pounds from Erythroxylum have been reported,among which only 186 tropane alkaloids have been reviewed in *** this review,we summarized all remained 197 compounds characterized from 53 Erythroxylum species from 1960 to 2021,which include diterpenes,triterpenes,alkaloids,flavonoids,and other derivates,providing a comprehensive overview of phytoconstituents profile of Erythroxylum *** addition,the biological activities of representative phytochemicals and crude extracts were also highlighted.

关键词： Erythroxylum Natural products Phytoconstituent Bioactivity

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IMTNet:Improved Multi-Task Copy-Move Forgery Detection Network with Feature Decoupling and Multi-Feature Pyramid

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Computers, Materials & Continua 2024年第9期80卷 4603-4620页

作者： Huan wang Hong wang Zhongyuan jiang Qing Qian yong Long School of Information Guizhou University of Finance and EconomicsGuiyang550025China College of Big Data Statistics Guizhou University of Finance and EconomicsGuiyang550025China

Copy-Move Forgery Detection(CMFD)is a technique that is designed to identify image tampering and locate suspicious ***,the practicality of the CMFD is impeded by the scarcity of datasets,inadequate quality and quantity,and a narrow range of applicable *** limitations significantly restrict the capacity and applicability of *** overcome the limitations of existing methods,a novel solution called IMTNet is proposed for CMFD by employing a feature decoupling ***,this study formulates the objective task and network relationship as an optimization problem using transfer ***,it thoroughly discusses and analyzes the relationship between CMFD and deep network architecture by employing ResNet-50 during the optimization solving ***,a quantitative comparison between fine-tuning and feature decoupling is conducted to evaluate the degree of similarity between the image classification and CMFD domains by the enhanced ***,suspicious regions are localized using a feature pyramid network with bottom-up path *** results demonstrate that IMTNet achieves faster convergence,shorter training times,and favorable generalization performance compared to ***,it is shown that IMTNet significantly outperforms fine-tuning based approaches in terms of accuracy and F_(1).

关键词： Image copy-move detection feature decoupling multi-scale feature pyramids passive forensics

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Refining the Factors Affecting N_(2)O Emissions from Upland Soils with and without Nitrogen Fertilizer Application at a Global Scale

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Advances in Atmospheric Sciences 2024年第9期41卷 1804-1820页

作者： Wenqian jiang Siqi LI yong LI Meihui wang Bo wang Ji LIU Jianlin SHEN Xunhua ZHENG State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory for Agro-ecological Processes in Subtropical Regions Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China Changsha Research Station for Agricultural&Environmental Monitoring Chinese Academy of SciencesChangsha 410125China University of Chinese Academy of Sciences Beijing 100049China State Environmental Protection Key Laboratory of Formation and Prevention of the Urban Air Pollution Complex Shanghai Academy of Environment SciencesShanghai 200233China Institute of Carbon Neutrality Qilu ZhongkeJinan 251699China Hubei Province Key Laboratory for Geographical Process Analysis and Simulation Central China Normal UniversityWuhan 430079China Department of Ecohydrology Leibniz Institute of Freshwater Ecology and Inland FisheriesBerlin 12587Germany Key laboratory of Environment Change and Resources Use in Beibu Gulf Ministry of EducationNanning Normal UniversityNanning 530001China Golden Mantis school of Architecture Soochow UniversitySuzhou 215123China

Nitrous oxide(N_(2)O)is a long-lived greenhouse gas that mainly originates from agricultural *** and more studies have explored the sources,influencing factors and effective mitigation measures of N_(2)O in recent ***,the hierarchy of factors influencing N_(2)O emissions from agricultural soils at the global scale remains *** this study,we carry out correlation and structural equation modeling analysis on a global N_(2)O emission dataset to explore the hierarchy of influencing factors affecting N_(2)O emissions from the nitrogen(N)and non-N fertilized upland farming systems,in terms of climatic factors,soil properties,and agricultural *** results show that the average N_(2)O emission intensity in the N fertilized soils(17.83 g N ha^(-1)d^(-1))was significantly greater than that in the non-N fertilized soils(5.34 g N ha^(−1) d^(−1))(p<0.001).Climate factors and agricultural practices are the most important influencing factors on N_(2)O emission in non-N and N fertilized upland soils,*** different climatic zones,without fertilizer,the primary influence factors on soil N_(2)O emissions are soil physical properties in subtropical monsoon zone,whereas climatic factors are key in the temperate *** fertilizer,the primary influence factors for subtropical monsoon and temperate continental zones are soil physical properties,while agricultural measures are the main factors in the temperate monsoon *** enhanced agricultural practices,such as reduced N fertilizer rate combined with the addition of nitrification and urease inhibitors can potentially mitigate N_(2)O emissions by more than 60%in upland farming systems.

关键词： N_(2)O emissions influencing factors nitrogen cycling upland farming systems

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On the Strong Approximation for a Simple Reentrant Line in Light Traffic Under First-buffer First-served Service Discipline

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 823-839页

作者： Kai-ming YANG yong-jiang GUO School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

For a 2-station and 3-class reentrant line under first-buffer first-served(FBFS)service discipline in light traffic,we firstly construct the strong approximations for performance measures including the queue length,workload,busy time and idle time *** on the obtained strong approximations,we use a strong approximation method to find all the law of the iterated logarithms(LILs)for the above four performance measures,which are expressed as some functions of system parameters:means and variances of interarrival and service times,and characterize the fluctuations around their fluid approximations.

关键词： reentrant line queueing network FBFS service discipline strong approximation LIL Brownian motion

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