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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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Methods to increase the diagnostic efficiency of endoscopic ultrasound-guided fine-needle aspiration for solid pancreatic lesions:An updated review

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World Journal of Gastrointestinal Endoscopy 2024年第3期16卷 117-125页

作者： Xin Yang zi-ming Liu Xue Zhou Fan Yang Wen-Zhuang Ma Xin-Zhu Sun Si-Yu Sun Nan Ge Department of Gastroenterology Shengjing Hospital of China Medical UniversityShenyang 110004Liaoning ProvinceChina

Endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA)is a means to procure adequate specimens for histological and cytologic *** ideal EUS-FNA should be safe,accurate,and have a high sample adequacy rate and low adverse events *** recent years,many guidelines and trials on EUS-FNA have been *** purpose of this article is to provide an update on the influence of some of the main factors on the diagnostic efficiency of EUS-FNA as well as a rare but serious complication known as needle tract seeding.

关键词： Endoscopic ultrasound EUS-FNA Pancreatic cancer Diagnostic efficiency

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基于自适应低秩表示的多任务AUC优化算法

计算机学报 2024年第11期47卷 2678-2690页

作者：孙宇辰许倩倩王子泰杨智勇黄庆明中国科学院计算技术研究所智能信息处理重点实验室北京100190 中国科学院大学计算机科学与技术学院北京101408 中国科学院信息工程研究所信息安全国家重点实验室北京100093 中国科学院大学网络空间安全学院北京100049 中国科学院大学大数据挖掘与知识管理重点实验室北京101408 鹏城实验室广东深圳518055

多任务学习是一种基于相似任务之间的关联性进行学习迁移,使得模型在数据不足场景下仍能表现出良好泛化性能的学习方法.在该领域内,大多数现有以准确率作为基准评价标准的方法只适用于平衡分布场景.然而,诸多实际应用如疾病检测、垃圾... 详细信息

多任务学习是一种基于相似任务之间的关联性进行学习迁移,使得模型在数据不足场景下仍能表现出良好泛化性能的学习方法.在该领域内,大多数现有以准确率作为基准评价标准的方法只适用于平衡分布场景.然而,诸多实际应用如疾病检测、垃圾邮件检测等,均涉及样本分布不平衡问题.针对多任务学习面向任务相关性的高要求,即当模型学习和共享不相关知识时,负迁移可能会影响模型朝着错误方向训练.因此,大多数现有方法在此类场景中无法得到有效应用.为解决该实际问题,设计一种能适用于样本不平衡场景的多任务学习算法变得尤为重要.本文提出了一种基于自适应低秩表示的多任务AUC优化算法,首先引入了对标签分布不敏感的ROC曲线下面积(AUC)作为该学习任务的评价指标,并建立了一种用于AUC优化的多任务学习算法,以提高模型在样本不平衡场景下的性能表现.同时,为进一步有效优化模型,本文将原始成对优化问题重构为逐样本极大极小优化问题,使得每一轮迭代复杂度由O(Ln_(i,+)n_(i,-))降低至O(L(n_(i,+)+n_(i,-))).针对多任务学习中存在的负迁移现象,本文引入了一种自适应低秩正则项,以消除模型冗余信息,同时提高模型的泛化性能.最后,通过与多个对比方法在四个仿真数据集和三个真实数据集Landmine、MHC-I和USPS上的比较,所有实验结果一致证明了本文所提出算法的有效性.

关键词：多任务学习 AUC优化低秩表示

太湖金墅港水源地蓝藻、细菌群落结构及垂直迁移规律研究

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长江流域资源与环境 2024年第3期33卷 596-604页

作者：林怡雯景明李继影吴志杰王子博清华苏州环境创新研究院江苏苏州215000 江苏省苏州环境监测中心江苏苏州215004

以太湖金墅港水源地蓝藻为研究对象,通过高通量测序技术分析水体和底泥中细菌的群落组成,同时检测常规水质理化因子,分析其对蓝藻变化的影响。结果显示,金墅港水体和底泥中细菌群落主要门组成相似,随着季节的变化水体中蓝藻群落结构的... 详细信息

以太湖金墅港水源地蓝藻为研究对象,通过高通量测序技术分析水体和底泥中细菌的群落组成,同时检测常规水质理化因子,分析其对蓝藻变化的影响。结果显示,金墅港水体和底泥中细菌群落主要门组成相似,随着季节的变化水体中蓝藻群落结构的变化较大,底泥中蓝藻的群落结构变化较小;蓝藻门主要的优势科是微囊藻科(Microcystaceae)和聚球藻科(Synechococcales),蓝藻爆发期主要是微囊藻;影响蓝藻群落结构变化的主要环境因子是水温、溶解氧、总氮和总磷;金墅港全年共检测到12个属的溶藻细菌,主要为假单胞菌(Pseudomonas)和黄杆菌(Flavobaeteria),溶藻菌在细菌的占比与蓝藻相反,蓝藻水华爆发时比例较低,蓝藻水华爆发前期、末期则比例较高。此外还发现随着气温升高,底泥中蓝藻的繁殖优先于水体中蓝藻的繁殖;蓝藻爆发期,水体中蓝藻比例较高时会出现向底泥中迁移富集的现象。

关键词：太湖金墅港细菌蓝藻溶藻细菌高通量测序

国家重点生态功能区县农村的“一老一小”问题研究

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山东行政学院学报 2024年第2期 64-72页

作者：王习明王子愿温州大学马克思主义学院浙江温州325035 温州医科大学马克思主义学院浙江温州325035

在中国式现代化的新征程中,国家重点生态功能区县农村面临着老人增收难、养老难、参与难和儿童上幼儿园、上小学难等现实困境,成为影响其共同富裕的重要因素。解决国家重点生态功能区县农村的“一老一小”问题,应取消或提高村干部的年... 详细信息

在中国式现代化的新征程中,国家重点生态功能区县农村面临着老人增收难、养老难、参与难和儿童上幼儿园、上小学难等现实困境,成为影响其共同富裕的重要因素。解决国家重点生态功能区县农村的“一老一小”问题,应取消或提高村干部的年龄上限,消除老人作用发挥的制度歧视和数字鸿沟,建立健全以老人为主体、低成本高质量服务老人的积极老龄化的乡村治理机制;统筹生态搬迁、新型城镇化、宜居宜业和美乡村建设,完善生态产品价值实现机制,优化幼儿园和小学的布局,探索充分发挥自然资源禀赋优势的乡村振兴道路;确立民生与生态相互促进的跨越式发展战略。

关键词：国家重点生态功能区县共同富裕农业型乡镇一老一小

Role of cyclic guanosine monophosphate-adenosine monophosphate synthase-stimulator of interferon genes pathway in diabetes and its complications

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World Journal of Diabetes 2024年第10期15卷 2041-2057页

作者： ming-Wei Fan Jin-Lan Tian Tan Chen Can Zhang Xin-Ru Liu zi-Jian Zhao Shu-Hui Zhang Yan Chen Department of Gastroenterology Binzhou Medical University HospitalBinzhou 256600Shandong ProvinceChina

Diabetes mellitus(DM)is one of the major causes of mortality worldwide,with inflammation being an important factor in its onset and *** review summarizes the specific mechanisms of the cyclic guanosine monophosphate-adenosine monophosphate synthase(cGAS)-stimulator of interferon genes(STING)pathway in mediating inflammatory ***,it compre-hensively presents related research progress and the subsequent involvement of this pathway in the pathogenesis of early-stage DM,diabetic gastroenteropathy,diabetic cardiomyopathy,non-alcoholic fatty liver disease,and other ***,the role of cGAS-STING in autonomic dysfunction and intes-tinal dysregulation,which can lead to digestive complications,has been ***,this study provides a comprehensive analysis of the research advances regarding the cGAS-STING pathway-targeted therapeutic agents and the prospects for their application in the precision treatment of DM.

关键词： Cyclic guanosine monophosphate-adenosine monophosphate synthase-stimulator of interferon genes Diabetes mellitus Inflammation Glycolipid metabolism Diabetes gastroenteropathy Nonalcoholic fatty liver disease Diabetes cardiovascular disease Diabetes nephropathy

磷化铁/生物碳复合材料活化亚硫酸盐降解橙黄Ⅱ的研究

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现代化工 2024年第8期44卷 115-120页

作者：高子航蔡明锦王雅博四川大学化学工程学院四川成都610065

水污染严重影响生态环境和人类健康,染料废水是其中的典型代表。利用酵母细胞作磷源和碳源,通过共沉淀-缺氧热解制备了磷化铁/生物碳复合材料,并将其作为高级氧化反应的催化剂,活化亚硫酸盐降解水体污染物橙黄Ⅱ。材料表征结果表明,磷... 详细信息

水污染严重影响生态环境和人类健康,染料废水是其中的典型代表。利用酵母细胞作磷源和碳源,通过共沉淀-缺氧热解制备了磷化铁/生物碳复合材料,并将其作为高级氧化反应的催化剂,活化亚硫酸盐降解水体污染物橙黄Ⅱ。材料表征结果表明,磷化铁的主要组成成分为Fe_(2)P和Fe_(3)P。在较优的催化条件下,经120 min吸附和催化联合处理,模拟废水中10 mg/L的橙黄Ⅱ可以被完全去除。催化反应机理分析表明,磷化铁/生物碳复合材料通过活化亚硫酸盐产生硫酸根自由基和羟基自由基,进而实现了橙黄Ⅱ的氧化降解。

关键词：高级氧化技术过渡金属磷化物生物碳染料废水降解

4种改良剂对酸性紫色土肥力及活性有机碳组分的影响

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环境科学 2024年第3期45卷 1655-1664页

作者：丁馨茹严宁珍王子芳李志琦黄容王洋代文才高明西南大学资源环境学院重庆400715 重庆市江津区农业技术推广中心重庆402260 四川农业大学资源学院成都611130

探究4种改良剂施用对酸性紫色土土壤肥力及活性碳组分特征影响,为紫色土养分管理及稳固碳库提供科学依据.采用田间试验,设置不施肥(CK)、单施化肥(F)、石灰+化肥(SF)、有机肥+化肥(OM)、生物炭+化肥(BF)及酒糟灰渣+化肥(JZ)这6个处理,... 详细信息

探究4种改良剂施用对酸性紫色土土壤肥力及活性碳组分特征影响,为紫色土养分管理及稳固碳库提供科学依据.采用田间试验,设置不施肥(CK)、单施化肥(F)、石灰+化肥(SF)、有机肥+化肥(OM)、生物炭+化肥(BF)及酒糟灰渣+化肥(JZ)这6个处理,研究不同处理土壤有机质、 pH、速效养分、土壤综合肥力指数(IFI)、溶解性有机碳(DOC)、微生物量碳(MBC)、颗粒有机碳(POC)含量及各组分有效率和土壤碳库管理指数(CPMI),阐明其相互关系.结果表明:(1)施用改良剂显著提高了土壤pH及有机质、碱解氮、速效磷、速效钾含量(PpH(11.7%)>AK(6.5%).酸性紫色土施用酒糟灰渣和有机肥提高土壤肥力和改良土壤质量效果最显著,同时有利于促进土壤碳组分的积累和活化.

关键词：改良剂紫色土活性碳组分综合肥力指数(IFI) 碳库管理指数(CPMI)

Effects of different processing methods on the quality of Polygonatum cyrtonema Hua

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TMR Modern Herbal Medicine 2024年第2期7卷 28-34页

作者： Xin-Ning Zhang Shuang-Hui Shi Jun-Li Zhang Fan-Miao Kong Hai-Ting Zhu Si-Yuan Ma Yu-Feng Hu ming-Rui Jiang Hui-Nan wang Meng-Lin wang Xiao-Tong Wei Jing-Qiu Zhang Nan Sun Meng-Yu Chen Qian-Qian Liu Ying-zi wang School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing 102488China

Background:In this study,we explored the effects of different processing methods on the quality of Polygonatum cyrtonema Hua(PC),and the role of Huangjiu in the processing ***:The sensory characteristics of the crude product,steamed product,and wine-processed product of PC were *** colorimeter was used to analyze the chromatic values of three different processed products on *** the same time,the contents of the water extract and alcohol extract were measured *** content of three different processing Polygonatum Polysaccharide(PCP)was determined using 0.2%anthrone-sulfuric *** correlation difference between the chromatic values and chemical composition of different PC products was analyzed using various analytical ***:The surface colors gradually deepened,the sweetness increased,the viscosity strengthened,and the tongue-numbing sensation disappeared after PC *** contents of extract and L^(*) gradually decreased from the crude to the steamed to the wine-processed product,consistent with the pattern of surface color ***,E^(*)ab gradually *** content of PCP was crude product>wine-processed product>steamed *** results of multivariate statistical analysis showed that the samples processed for crude,steamed,and wine-processed product were clustered into three *** correlation analysis showed that L^(*)and E^(*)ab were highly significant positively correlated with the content of PCP,and a*was significantly negatively correlated with the content of ***:The results showed that the wine-processed product had the best *** internal quality of the PC was correlated with its characteristics and chromatic *** this study,we investigated the internal and external quality of three different products of PC in order to provide a reference for further research on the impact of different processing methods on PC quality,the standardization of PC processing,and the

关键词： Polygonatum cyrtonema Hua different products chemical composition chromatic value characteristics