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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 2025年第1期68卷 288-296页

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 Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A 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.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

Epigenetics in the modern era of crop improvements

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Science China life Sciences 2025年

作者： Yan xue xiaofeng cao Xiangsong Chen Xian Deng Xingwang Deng Yong Ding Aiwu Dong Chengguo Duan xiaofeng Fang Lei Gong Zhizhong Gong xiaofeng Gu Chongsheng He Hang He Shengbo He Xinjian He Yan He Yuehui He Guifang Jia Danhua Jiang Jianjun Jiang jinsheng Lai Zhaobo Lang Chenlong li Qing li Xingwang li Bao liu Bing liu xiao Luo Yijun Qi Weiqiang Qian Guodong Ren Qingxin Song Xianwei Song Zhixi Tian Jiawei Wang Yuan Wang liang Wu Zhe Wu Rui Xia jun xiao lin xu Zhengyi xu Wenhao Yan Hongchun Yang Jixian Zhai Yijing Zhang Yusheng Zhao xuehua Zhong Daoxiu Zhou ming Zhou Yue Zhou Bo Zhu Jiankang Zhu Qikun liu College of life Sciences Institute of Life Science and Green Development Hebei University Biotechnology Research Institute Chinese Academy of Agricultural Sciences College of Biology Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation Hunan Engineering and Technology Research Center of Hybrid Rapeseed Hunan University Institute of Advanced Agricultural Sciences School of Advanced Agricultural Sciences Peking University State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural University National Institute of Biological Sciences Key Laboratory of Seed Innovation Institute of Genetics and Developmental Biology Chinese Academy of Sciences School of Advanced Agricultural Sciences Peking-Tsinghua Center for Life Sciences Peking University Synthetic and Functional Biomolecules Center Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Key Laboratory of Seed Innovation State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences State Key Laboratory of Wheat Improvement Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory of Advanced Agricultural Sciences in Weifang State Key Laboratory of Crop Stress Adaptation and Improvement School of Life Sciences Henan University State Key Laboratory of Maize Bio-breeding National Maize Improvement Center Department of Plant Genetics and Breeding China Agricultural University Frontiers Science Center for Molecular Design Breeding China Agricultural University Center for Crop Functional Genomics and Molecular Breeding China Agricultural University Sanya Institute of China Agricultural University Hainan Yazhou Bay Seed Laboratory Institute of Advan

Epigenetic mechanisms are integral to plant growth, development, and adaptation to environmental stimuli. Over the past two decades,our comprehension of these complex regulatory processes has expanded remarkably, producing a substantial body of knowledge on both locus-specific mechanisms and genome-wide regulatory patterns. Studies initially grounded in the model plant Arabidopsis have been broadened to encompass a diverse array of crop species, revealing the multifaceted roles of epigenetics in physiological and agronomic traits. With recent technological advancements, epigenetic regulations at the single-cell level and at the large-scale population level are emerging as new focuses. This review offers an in-depth synthesis of the diverse epigenetic regulations, detailing the catalytic machinery and regulatory functions. It delves into the intricate interplay among various epigenetic elements and their collective influence on the modulation of crop traits. Furthermore, it examines recent breakthroughs in technologies for epigenetic modifications and their integration into strategies for crop improvement. The review underscores the transformative potential of epigenetic strategies in bolstering crop performance, advocating for the development of efficient tools to fully exploit the agricultural benefits of epigenetic insights.

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Analysis on the influencing factors of radioactive tritium leakage and diffusion from an indoor high‑pressure storage vessel

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Nuclear Science and Techniques 2022年第12期33卷 1-11页

作者： Chang‑jun li Xing‑Fu Cai ming‑Qing xiao Yong‑Gang Huo Peng xu Su‑Fen li xiao‑Yan cao Xi’an Research Institute of High-Tech Xi’an 710025China Air Force Engineering University Xi’an 710051China

Radioactive tritium leakage from high-pressure storage vessels is a common nuclear leakage *** leakage conditions have different effects on tritium diffusion,resulting in different degrees of radioactive *** study focuses on tritium leakage from high-pressure storage vessels and analyzes the influence of different leakage orifice shapes,leakage positions,and the presence of obstacles in the scene space on tritium leakage *** results show that there is little difference in the radial diffusion velocity of tritium gas along the jet axis between circular and square leakage *** radial diffusion velocity of tritium gas in the long-axis direction of the rectangular leakage orifice is larger than that in the short-axis direction,and the larger the aspect ratio of the rectangle is,the greater the difference is in the diffusion *** addition,leakage from the storage vessel below the air inlet is beneficial to the dilution of tritium,whereas leakage from the air vents leads to a slow decrease in the tritium *** obstacles present in the tritium scene space hinder the migration of tritium gas and prolong the time for the tritium concentration to reach *** study provides a theoretical basis for the disposal of tritium in tritium leakage accidents by analyzing the influence of different leakage conditions in storage vessels on tritium gas diffusion.

关键词： Tritium leakage Leakage orifice shape Leakage position Obstacles

Diurnal macular choroidal area fluctuation in normal and primary open angle glaucoma groups

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International Journal of Ophthalmology(English edition) 2017年第8期10卷 1233-1238页

作者： Mu li jin-Min Guo xiao-Lan xu jun-ming Wang Department of Ophthalmology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei Province China Department of Ultrasound Tongji Hospital Tongji MedicalCollege Huazhong University of Science and TechnologyWuhan 430030 Hubei Province China

AIM： To assess and compare the diurnal macular choroidal area fluctuation in normal and primary open angle glaucoma （POAG） groups using enhanced depth imaging optical coherence tomography （EDI-OCT）. METHODS： Twenty-eight normal and 27 POAG eyes were enrolled in this study. EDI-OCT was used to measure the macular choroidal area every 3h from 9：00 a.m. to 21：00 p.m. RESULTS： Significant diurnal fluctuations of macular choroidal area were observed in both normal （P=-0.003） and POAG groups （P〈0.001）. But no significant macular choroidal area difference has been found between the two groups at all the five measurement time-points （512778＋166242 vs 455079：1：207278 pm2, P=-0.195 at 9：00 a.m.; 501526168953 vs 447846.：211147 pm2, P=-0.245 at 12：00 a.m.; 501982＋173158 vs 448024#.206653 pm2, P=-0.239 at 15：00 p.m.; 508912＋174589 vs 457783＋-207081 pm2, P=-0.252 at 18：00 p.m.; 503787＋171241 vs 453230＋_205955 pm2, P=-0.274 at 21：00 p.m.; respectively）. Furthermore, neither the fluctuation manners nor the change in macular choroidal area between the two adjacent measurement time points showed significant difference between normal and POAG groups （all P〉0.05）. In the meantime, significant diurnal intraocular pressure fluctuations were also observed in normal and POAG groups （both P〈0.001）. CONCLUSION： In diurnal time, the macular choroidal area in both normal and POAG groups fluctuated significantly; moreover, neither the value of macular choroidal area, nor the fluctuation of macular choroidal area in POAG group is significantly different from that in normal group.

关键词： diurnal fluctuation macular choroidal area primary open angle glaucoma optical coherence tomography

Pore structure evolution of lacustrine organic-rich shale from the second member of the Kongdian formation in the Cangdong Sag,Bohai Bay Basin,China

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Petroleum Science 2022年第2期19卷 459-471页

作者： xiao-Ping liu ming Guan Zhi-jun jin Zhe cao jin Lai Lun-Ju Zheng Wen-Qi li Biao Sun Shan-Yong Chen State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Research Institute of Petroleum Exploration and Development China National Petroleum CorporationBeijing100083China Institute of Energy Peking UniversityBeijing100871China State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing100083China Sinopec Petroleum Exploration and Production Research Institute Beijing102206China Wuxi Petroleum Geology Institute Research Institute of Petroleum Exploration and DevelopmentSinopecWuxiJiangsu 214126China Petro China Dagang Oil Field Company Tianjin300280China

Pyrolysis experiments were conducted on lacustrine organic-rich shale from Cangdong Sag in Bohai Bay Basin,China,to investigate the impact of hydrocarbon generation on shale pore structure *** evolution is found to control the transformation of organic matter,hydrocarbon products characteristics,and pore structure ***,pore volume and specific surface area increase with increasing *** low-mature stage,the retained oil content begins to increase,pore volumes show slight changes,and primary pores are occluded by the generated crude oil of high molecular weight and *** the oil-window stage,the retained oil content rapidly increases and reaches maximum,and pore volumes gradually increase with increasing thermal *** high mature stage,the retained oil content begins to decrease,and the pore volume increases considerably owing to the expulsion of liquid *** over mature stage,natural gas content significantly increases and kerogen transforms to *** organic pores are formed and the pore size gradually increases,resulting from the connection of organic pores caused the increasing thermal *** study lays a foundation for understanding variation of hydrocarbon products during the thermal evolution of lacustrine shales and its relationship with the evolution of shale reservoirs.

关键词： Lacustrine shale Pyrolysis Thermal maturity Pore structure evolution Hydrocarbon generation evolution

Cooling process of iron ore pellets in an annular cooler

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 285-291页

作者： jun-xiao Feng Kai-li liang Zhi-bin Sun jing-hai xu Yong-ming Zhang jin-bao Yang School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China Shougang Mining Company Qianan 064404 China

A 3-D mathematical model was presented for the cooling process of iron ore pellets based on the laws of mass, momentum, and heat transfer. The flow, pressure, and temperature fields were obtained by numerical simulation with the commercial software FLUENT. In order to verify the model, a mass and energy balance field test was systematically carried out on an annular cooler in Shougang Mining Company. The maximum relative errors of temperature, pressure, and velocity between computational and testing results are 2.87%, -8.11%, and 7.14%, respectively, indicating the validity of the model. Further, the effects of process parameters, such as pellet diameter, bed thickness, air velocity, and temperature, on the pellet bed temperature profiles were studied.

关键词： iron ore pellets mathematical models cooling numerical analysis

Abnormal brain activity in adolescents with Internet addiction who attempt suicide: an assessment using functional magnetic resonance imaging

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Neural Regeneration Research 2020年第8期15卷 1554-1559页

作者： Yan Huang Lu xu li Kuang Wo Wang jun cao Mu-Ni xiao GCP Office Chongqing Traditional Chinese Medicine HospitalChongqingChina Chongqing Medical and Pharmaceutical College ChongqingChina Department of Psychiatry the First Affiliated Hospital of Chongqing Medical UniversityChongqingChina Mental Health Center University-Town Hospital of Chongqing Medical UniversityChongqingChina

Internet addiction is associated with an increased risk of suicidal behavior and can lead to brain dysfunction among ***,whether brain dysfunction occurs in adolescents with Internet addiction who attempt suicide remains *** observational cross-sectional study enrolled 41 young Internet addicts,aged from 15 to 20 years,from the Department of Psychiatry,the First Affiliated Hospital of Chongqing Medical University,China from January to May *** participants included 21 individuals who attempted suicide and 20 individuals with Internet addiction without a suicidal attempt *** images in the resting state were obtained by a 3.0 T magnetic resonance imaging *** results showed that activity in the gyrus frontalis inferior of the right pars triangularis and the right pars opercularis was significantly increased in the suicidal attempt group compared with the non-suicidal attempt *** the resting state,the prefrontal lobe of adolescents who had attempted suicide because of Internet addiction exhibited functional abnormalities,which may provide a new basis for studying suicide pathogenesis in Internet *** study was authorized by the Ethics Committee of Chongqing Medical University,China(approval No.2017 Scientific Research Ethics(2017-157))on December 11,2017.

关键词： adolescents amplitude of low-frequency fluctuation brain activity functional magnetic resonance imaging Internet addiction prefrontal lobe resting state suicidal attempt

Stable 4.5 V liCoO_(2)cathode material enabled by surface manganese oxides nanoshell

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Nano Research 2023年第2期16卷 2480-2485页

作者： jun Wang Si-Dong Zhang Si-Jie Guo Si-Qi Lu Yan-Song xu jin-Yang li An-Min cao li-jun Wan CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing 100190China University of Chinese Academy of Sciences(UCAS) Beijing 100049China

Charging the liCoO_(2)(LCO)cathode to a higher voltage,for example 4.5 V compared to the commonly used 4.2 V,is now intensively pursued so as to achieve a higher specific ***,it suffers severe surface structural degradation and detrimental interfacial side reactions between cathode and electrolyte,which lead to the fast capacity fading during long-term ***,a surface coating strategy was developed for the protection of 4.5 V LCO by constructing a manganese oxides(MOs)nanoshell around LCO particles,which was achieved through a solution-based coating process with success in controlling the growth kinetics of the coating *** found that the introduction of the MOs nanoshell is highly effective in alleviating the organic electrolyte decomposition at the cathode surface,thus ensuring a much more stable liF-rich cathode-electrolyte interface and an obvious lower interfacial resistance during electrochemical ***,this protection layer can effectively improve the structural stability of the cathode by hindering the cracks formation and structural degradation of LCO ***,the MOs modified LCO exhibited excellent rate performance and a high discharge capacity retention of 81.5%after 100 cycles at 1 C compared with the untreated LCO(55.2%),as well as the improved thermal stability and cyclability at the elevated *** is expected that this discovery and fundamental understanding of the surface chemistry regulation strategy provide promising insights into improving the reversibility and stability of LCO cathode at the cut-off voltage of 4.5 V.

关键词： lithium-ion battery 4.5 V liCoO_(2) manganese oxides surface coating interfacial stability regulation

Hemodynamic characteristics in preeclampsia women during cesarean delivery after spinal anesthesia with ropivacaine

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World Journal of Clinical Cases 2020年第8期8卷 1444-1453页

作者： Na Zhao jin xu xiao-Guang li Joseph Harold Walline Yi-Chong li lin Wang Guo-Sheng Zhao ming-jun xu Department of Anesthesiology Beijing Obstetrics and Gynecology HospitalCapital Medical UniversityBeijing 100026China Department of Emergency Medicine Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Accident and Emergency Medicine Academic Unit Prince of Wales HospitalThe Chinese University of Hong KongHong Kong 9990777China Department of Clinical Research and Epidemiology National Clinical Research Center for Cardiovascular DiseasesFuwai HospitalChinese Academy of Medical SciencesBeijing 100037China

BACKGROUND Very few studies have been published on the hemodynamic changes associated with spinal anesthesia induced with ropivacaine during cesarean deliveries in preeclamptic *** To record and analyze hemodynamic data in women with preeclampsia undergoing cesarean delivery after spinal anesthesia induced with *** Ten eligible women with preeclampsia were enrolled in this prospective observational *** anesthesia was performed with 2.4 mL of 0.5%*** changes were then analyzed at multiple time *** hemodynamic responses to vasopressor interventions and uterotonic agents,as well as maternal and neonatal outcomes were also *** Stable hemodynamic trends were observed in this *** output(CO)and stroke volume increased mildly during *** contrast,mean arterial pressure and systemic vascular resistance showed a moderate decrease from induction until the end of *** venous pressure dramatically increased after *** administration was associated with the most significant hemodynamic fluctuations during surgery,namely,an increase in CO and heart *** intervention was only required in three patients,and caused an increase in mean arterial pressure and systemic vascular resistance along with a decrease in heart rate,stroke volume,and *** maternal and neonatal complications were observed during this study,except transient episodes of *** Spinal anesthesia for caesarian delivery with ropivacaine in women with preeclampsia is linked to modest hemodynamic changes of no clinical significance in this *** cardiovascular monitoring is still recommended,particularly after the delivery of the fetus or the use of oxytocin.

关键词： Preeclampsia Cesarean delivery Spinal anesthesia Cardiac output Hemodynamics