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Full biosynthetic pathway of pyrrolobenzoxazines

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Chinese Chemical Letters 2025年第1期36卷 433-436页

作者： Kunya Wang Bingyu Liu Daojiang Yan Jian Bai Haibo Yu Youcai hu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Pyrrolobenzoxazines are a rare terpene-amino acid family of natural products with potent biological ***,we reported the full biosynthetic pathway of paeciloxazine(1),a typical pyrrolobenzoxazine,with significant insecticidal *** on heterologous expression,chemical complement experiment,and in vitro biochemical assays,we demonstrated the sesquiterpene portion of 1 derived from discontinuously oxidations of amorphdiene,in which P450 monooxygenase PaxH catalyzed a cascade of hydroxylation and epoxidation,while two flavin dependent monooxygenases are involved in the transformation of the esterified tryptophan into a pyrrolobenzoxazine ***,a total of 15 compounds were generated through heterologous expression,of which 13,17 and 20 showed potential antiepileptic *** study fully elucidated the biosynthetic pathway of paeciloxazine(1)and showed the diversity and complexity of constructing natural products by organisms.

关键词： Pyrrolobenzoxazines Paeciloxazine Biosynthesis P450 monooxygenase Antiepileptic activity

Unraveling brain aging through the lens of oral microbiota

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Neural Regeneration Research 2025年第7期20卷 1930-1943页

作者： Qinchao hu Si Wang Weiqi Zhang Jing Qu Guang-hui Liu State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Hospital of Stomatology Guanghua School of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Advanced Innovation Center for human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu HospitalCapital Medical UniversityBeijingChina Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijingChina CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijingChina University of Chinese Academy of Sciences BeijingChina Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijingChina Aging Biomarker Consortium BeijingChina State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Beijing Institute for Stem Cell and Regenerative Medicine BeijingChina

The oral cavity is a complex physiological community encompassing a wide range of *** of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative *** studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention *** this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and *** also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging.

关键词： Alzheimer's disease brain aging multiple sclerosis neurodegeneration neurodegenerative diseases oral microbiota Parkinson's disease periodontitis bacteria Porphyromonas gingivalis

KDM2A and KDM2B protect a subset of CpG islands from DNA methylation

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Journal of Genetics and Genomics 2025年第1期52卷 39-50页

作者： Yuan Liu Ying Liu Yunji Zhu Di hu hu Nie Yali Xie Rongrong Sun Jin He Honglian Zhang Falong Lu State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Biochemistry&Molecular Biology College of Natural ScienceMichigan State UniversityEast LansingMI 48824US State Key Laboratory of Animal Nutrition and Feeding Institute of Animal SciencesChinese Academy of Agricultural SciencesBeijing 100193China

In the mammalian genome,most CpGs are ***,CpGs within the CpG islands(CGIs)are largely unmethylated,which are important for gene expression *** mechanism underlying the low methylation levels at CGIs remains largely ***2 proteins(KDM2A and KDM2B)are H3K36me2 demethylases known to bind specifically at ***,we report that depletion of each or both KDM2 proteins,or mutation of all their JmjC domains that harbor the H3K36me2 demethylation activity,leads to an increase in DNA methylation at selective *** Kdm2a/2b double knockout shows a stronger increase in DNA methylation compared with the single mutant of Kdm2a or Kdm2b,indicating that KDM2A and KDM2B redundantly regulate DNA methylation at *** addition,the increase of CGI DNA methylation upon mutations of KDM2 proteins is associated with the chromatin *** findings reveal that KDM2A and KDM2B function redundantly in regulating DNA methylation at a subset of CGIs in an H3K36me2 demethylation-dependent manner.

关键词： KDM2A KDM2B CpG island DNA methylation H3K36me2 Demethylation Embryonic stemcell

财政管理体制与中国地方公共服务均衡保障:研究状况及未来展望

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技术经济 2025年第1期44卷 80-87页

作者：卢盛峰黄坤武汉大学经济与管理学院武汉430072

近些年来,地方公共服务均衡保障问题日益受到社会各界的广泛关注。党的二十大报告及二十届三中全会决定中也都强调要“增强基本公共服务均衡性和可及性”。而如何更好地理顺多级政府间的财政管理关系,完善和做好激励设计,充分发挥好“... 详细信息

近些年来,地方公共服务均衡保障问题日益受到社会各界的广泛关注。党的二十大报告及二十届三中全会决定中也都强调要“增强基本公共服务均衡性和可及性”。而如何更好地理顺多级政府间的财政管理关系,完善和做好激励设计,充分发挥好“上级政府”和“地方政府”在公共服务供给中的两个积极性,对于保障公共服务的均衡性和可及性供给尤为重要。本文将从财政管理体制角度切入,对中国地方公共服务均衡保障的相关理论文献进行梳理。研究发现:第一,中国地方公共服务供给存在明显的地区差异和城乡差异,特别是教育、医疗公共服务供给不均衡问题尤为突出;第二,财政分权体制、地方政府的晋升激励及财政支出结构等因素是导致地方公共服务供给失衡的重要原因;第三,增加公共支出、提高转移支付、推进户籍改革、鼓励政府购买服务等公共政策都有助于改善地方公共服务供给状况;第四,事权与支出责任划分、政府间财政关系的优化设计等财政管理体制改革措施对地方公共服务供给的均衡性和可及性具有显著影响。

关键词：财政管理体制公共服务均衡财政分权晋升激励

A dynamical approach to generalized Weil's Riemann hypothesis and semisimplicity In memory of Professor Gang Xiao

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Science China Mathematics 2025年

作者： Fei hu Tuyen Trung Truong School of Mathematics Nanjing University Department of Mathematics University of Oslo Department of Mathematics Harvard University

Let f be a dynamical correspondence of a smooth projective variety X over an algebraically closed field of arbitrary characteristic. In 2016, Truong conjectured that the dynamical degrees of f defined via the pullback actions on-adic étale cohomology groups and on numerical cycle class groups are equivalent, which we call the dynamical degree comparison(DDC) conjecture. It contains the generalized Weil's Riemann hypothesis(for polarized endomorphisms) as a particular case. In this paper, we introduce a quantitative strengthening of the standard conjecture C, named as Conjecture Gr, and show that it holds on abelian varieties and Kummer surfaces. We prove that Conjecture Gryields the generalized Weil's Riemann hypothesis. Moreover,Conjecture Grplus the standard conjecture D imply the norm comparison conjecture, whose consequences include the DDC conjecture and the generalized semisimplicity conjecture. As applications, we prove the DDC conjecture for algebraically stable dynamical correspondences of abelian varieties and Kummer surfaces,extending hu's previous work(2019, 2024) on endomorphisms of abelian varieties. We also obtain a similar comparison result for effective finite correspondences of abelian varieties and prove the generalized semisimplicity conjecture for Kummer surfaces.

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First observation results of Macao Science Satellite-1 on lightning-induced electron precipitation

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Science China Earth Sciences 2025年第1期68卷 1-10页

作者： Yongping WANG Yixin SUN Qiugang ZONG Gaopeng LU Xudong GU Ze-Jun hu Bin LI Key Laboratory for Polar Science Ministry of Natural ResourcesPolar Research Institute of ChinaShanghai 200136China Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China State Key Laboratory of Lunar and Planetary Science Macao University of Science and TechnologyMacao 999078China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Electronic Information Wuhan UniversityWuhan 430072China

The Medium-energy Electron Spectrometers(MES)is a space-borne instrument onboard Macao Science Satellite-1(MSS-1)dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development,including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch,all within the range of 1.5

关键词： Lightning-induced electron precipitation Inner radiation belts Energetic electrons Macao Science Satellite-1

Experimental Study for Effect of Multi-Site Spark Ignition on Dedicated Hybrid Engine Performance under High Dilution Condition

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Journal of Thermal Science 2025年第1期34卷 254-267页

作者： YAN Bowen WATERS Benjamin HAINES Andrew MCGHEE Mike hu Tiegang DENG Wei PU Yongxian MA Tianyu Powertrain Engineering R&D Center Chongqing Changan Automobile Co.Ltd.Chongqing 400000China Changan UK R&D Centre Limited Birmingham B377YGUnited Kingdom

In this study,a triple spark ignition scheme was first designed on a three-cylinder 1.5-L dedicated hybrid engine(DHE).On this basis,the effect of different ignition modes on engine combustion and emission characteristics was studied,especially under high dilution *** results tested at 2000 r/min and 0.8 MPa BMEP(brake mean effective pressure)show that with highly increased in-cylinder flow intensity,using only passive prechamber(PPC)has a lower lean limit than that with single central spark plug(CSP),thereby leading to slightly higher minimum fuel consumption and nitrogen oxides(NO_(x))*** side spark plugs(SSP)based on PPC can result in improved capability of lean limit extension and engine performance than ***,the improvement level is lower than that with triple spark plugs(TSP).As the excess air ratio λ increases,the advantage of PPC and PPC with SSP in improving the combustion phasing compared with CSP gradually ***,the increasing tendency of their ignition delay and combustion duration is more *** added SSP based on PPC can effectively shorten the ignition delay of leaner mixture,but the combustion duration can be only slightly *** a result,under extremely lean condition,the advantage of PPC and PPC with SSP in terms of combustion characteristics over CSP becomes much *** contrast,the TSP ignition can achieve much shorter ignition delay and combustion duration simultaneously under this *** to the highest available dilution level,the TSP ignition achieves the lowest raw NO_(x)***,it can also reduce the raw carbon monoxide(CO)and hydrocarbons(HC)emissions compared to CSP due to a more thorough combustion of the end gas *** on the excellent performance of TSP,the highest engine brake thermal efficiency(BTE)was further *** results show that with normal RON 92 fuel,the engine finally achieved 43.69% and 45.02% BTE under stochiometric mode with exhaus

关键词： dedicated hybrid engine triple spark plug scheme passive prechamber high dilution condition thermal efficiency NO_(x)emissions

Development of Leisure Sports Industry Clusters in Sichuan Province Based on Resource Competitiveness

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Journal of Resources and Ecology 2025年第1期16卷 245-252页

作者： GUO Jianying WEI Yating hu Shiwei School of Tourism and Geographic Sciences Leshan Normal UniversityLeshanSichuan 614000China College of Tourism Northwest Normal UniversityLanzhou 730070China The Engineering&Technical College Chengdu University of TechnologyLeshanSichuan 614007China

Sichuan Province has abundant leisure sports *** evaluation of the competitiveness of its leisure sports resources can provide a scientific basis for the selection and development of leisure sports industry clusters in Sichuan *** addition,a competitiveness evaluation index system for leisure sports resources was constructed to assess the competitiveness of leisure sports resources for 21 regions in Sichuan *** results showed significant differences among the 21 regions,and they could be divided into three ***,the first level included the seven regions of Chengdu,Leshan,Yibin,Mianyang,Zigong,Aba and Luzhou;the second level included the 11 regions of Ya’an,Guangyuan,Ganzi,Neijiang,Deyang,Guang’an,Liangshan,Nanchong,Panzhihua,Bazhong and Dazhou;and the third level included Meishan,Suining and *** view of the resource conditions,environmental conditions,and development conditions,Chengdu,Leshan,Yibin,Mianyang,and Zigong were chosen as the most suitable areas for leisure sports industry clusters in Sichuan ***,suggestions for these five potential leisure sports industry clusters were proposed to promote the high-quality development of the sports industry in Sichuan Province.

关键词： leisure sports resources resource competitiveness leisure sports industry cluster Sichuan

Recent advances,strategies,and future perspectives of peptide-based drugs in clinical applications

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Chinese Journal of Natural Medicines 2025年第1期23卷 31-42页

作者： Qimeng Yang Zhipeng hu Hongyu Jiang Jialing Wang Han Han Wei Shi Hai Qian Centre of Drug Discovery State Key Laboratory of Natural Medicines China Pharmaceutical University Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease China Pharmaceutical University

Peptide-based therapies have attracted considerable interest in the treatment of cancer, diabetes, bacterial infections, and neurodegenerative diseases due to their promising therapeutic properties and enhanced safety profiles. This review provides a comprehensive overview of the major trends in peptide drug discovery and development, emphasizing preclinical strategies aimed at improving peptide stability, specificity, and pharmacokinetic properties. It assesses the current applications and challenges of peptide-based drugs in these diseases, illustrating the pharmaceutical areas where peptide-based drugs demonstrate significant potential. Furthermore, this review analyzes the obstacles that must be overcome in the future,aiming to provide valuable insights and references for the continued advancement of peptidebased drugs.

关键词： Antimicrobial peptides Diabetes Neurodegenerative diseases Oncology Peptide-based drugs