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Straw mulching alters the composition and loss of dissolved organic matter in farmland surface runoff by inhibiting the fragmentation of soil small macroaggregates

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Journal of Integrative Agriculture 2024年第5期23卷 1703-1717页

作者： Shanshan Cai Lei sun Wei Wang Yan Li Jianli Ding Liang Jin yumei Li Jiuming Zhang Jingkuan Wang Dan Wei College of Land and Environment Shenyang Agricultural UniversityShenyang 110866China Heilongjiang Academy of Black Soil Conservation and Utilization Harbin 150086China Institute of Plant Nutrition Resources and EnvironmentBeijing Academy of Agricultural and Forestry SciencesBeijing 100097China

Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How straw mulching affects the composition and loss of runoff DOM by changing soil aggregates remains largely unclear.Here,a straw mulching treatment was compared to a no mulching treatment(as a control)on sloping farmland with black soil erosion in Northeast China.We divided the soil into large macroaggregates(>2 mm),small macroaggregates(0.25-2 mm),and microaggregates(<0.25 mm).After five rain events,the effects of straw mulching on the concentration(characterized by dissolved organic carbon(DoC)and composition(analyzed by fluorescence spectroscopy)of runoff and soil aggregate DOM were studied.The results showed that straw mulching reduced the runoff amount by 54.7%.Therefore,although straw mulching increased the average DOc concentration in runoff,it reduced the total runoff DOM loss by 48.3%.The composition of runoff DOM is similar to that of soil,as both contain humic-like acid and protein-like components.With straw mulching treatment,the protein-like components in small macroaggregates accumulated and the protein-like components in runoff declined with rain events.Fluorescence spectroscopy technology may help in understanding the hydrological paths of rain events by capturing the dynamic changes of runoff and soil DOM characteristics.A variation partitioning analysis(VPA)indicated that the DOM concentration and composition of microaggregates explained 68.2%of the change in runoff DOM from no mulching plots,while the change in runoff DOM from straw mulching plots was dominated by small macroaggregates at a rate of 55.1%.Taken together,our results demonstrated that straw mulching reduces the fragmentation of small macroaggregates and the loss of microaggregates,thus effecting DOM compositions in soil and reducing the DOM loss in runoff.These results provide a theoretical basis for reducing carbon loss

关键词： dissolved organic matter black soil surface runoff aggregates fluorescence spectrum

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Melatonin biosynthesis pathways in nature and its production in engineered microorganisms

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Synthetic and Systems Biotechnology 2022年第1期7卷 544-553页

作者： Xiaotong Xie Dongqin Ding Danyang Bai Yaru Zhu Wei sun yumei sun Dawei Zhang Dalian Polytechnic University Dalian116000PR China Tianjin Institutes of Industrial Biotechnology Chinese Academy of SciencesTianjin300308PR China Biodesign Center Tianjin Institute of Industrial BiotechnologyChinese Academy of SciencesTianjin300308PR China Tianjin University of science and technology Tianjin300308PR China

Melatonin is a biogenic amine that can be found in plants,animals and microorganism.The metabolic pathway of melatonin is different in various organisms,and biosynthetic endogenous melatonin acts as a molecular signal and antioxidant protection against external stress.Microbial synthesis pathways of melatonin are similar to those of animals but different from those of plants.At present,the method of using microorganism fermentation to produce melatonin is gradually prevailing,and exploring the biosynthetic pathway of melatonin to modify microorganism is becoming the mainstream,which has more advantages than traditional chemical synthesis.Here,we review recent advances in the synthesis,optimization of melatonin pathway.L-tryptophan is one of the two crucial precursors for the synthesis of melatonin,which can be produced through a four-step reaction.Enzymes involved in melatonin synthesis have low specificity and catalytic efficiency.Site-directed mutation,directed evolution or promotion of cofactor synthesis can enhance enzyme activity and increase the metabolic flow to promote microbial melatonin production.On the whole,the status and bottleneck of melatonin biosynthesis can be improved to a higher level,providing an effective reference for future microbial modification.

关键词： Melatonin Biosynthesis Plants Animals Microorganisms Metabolic modification Enzyme catalysis mechanism

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Large-scale loss-of-function perturbations reveal a comprehensive epigenetic regulatory network in breast cancer

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Cancer Biology & Medicine 2024年第1期21卷 83-103页

作者： yumei Wang Haiyan Wang Wei Shao Yuhui Chen Yu Gui Chao Hu Xiaohong Yi Lijun Huang Shasha Li Dong Wang School of Basic Medical Sciences State Key Laboratory of Southwestern Chinese Medicine ResourcesChengdu University of Traditional Chinese MedicineChengdu 611137China Department of Pathology School of MedicineQinghai UniversityXining 810001China Omics Biosciences Inc Beijing 100871China Laboratory of Integrative Medicine Clinical Research Center for BreastState Key Laboratory of BiotherapyWest China HospitalSichuan University and Collaborative Innovation CenterChengdu 610041China State Key Laboratory of Southwestern Chinese Medicine Resources School of PharmacyChengdu University of Traditional Chinese MedicineChengdu 611137China Department of Endocrinology and Metabolism Guangdong Provincial Key Laboratory of Diabetology&Guangzhou Municipal Key Laboratory of Mechanistic and Translational Obesity ResearchMedical Center for Comprehensive Weight ControlThe Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510630China

Objective:Epigenetic abnormalities have a critical role in breast cancer by regulating gene expression;however,the intricate interrelationships and key roles of approximately 400 epigenetic regulators in breast cancer remain elusive.It is important to decipher the comprehensive epigenetic regulatory network in breast cancer cells to identify master epigenetic regulators and potential therapeutic targets.Methods:We employed high-throughput sequencing-based high-throughput screening(HTS^(2))to effectively detect changes in the expression of 2,986 genes following the knockdown of 400 epigenetic regulators.Then,bioinformatics analysis tools were used for the resulting gene expression signatures to investigate the epigenetic regulations in breast cancer.Results:Utilizing these gene expression signatures,we classified the epigenetic regulators into five distinct clusters,each characterized by specific functions.We discovered functional similarities between BAZ2B and SETMAR,as well as CLOCK and CBX3.Moreover,we observed that CLOCK functions in a manner opposite to that of HDAC8 in downstream gene regulation.Notably,we constructed an epigenetic regulatory network based on the gene expression signatures,which revealed 8 distinct modules and identified 10 master epigenetic regulators in breast cancer.Conclusions:Our work deciphered the extensive regulation among hundreds of epigenetic regulators.The identification of 10 master epigenetic regulators offers promising therapeutic targets for breast cancer treatment.

关键词： Epigenetic regulators breast cancer regulatory network HTS^(2)

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High-rate CH_(4)-to-C_(2)H_(6) photoconversion enabled by Au/ZnO porous nanosheets under oxygen-free system

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Science China Chemistry 2024年第3期67卷 869-875页

作者： Kai Zheng Xiaojing Zhang Jun Hu Chengbin Xu Juncheng Zhu Jing Li Mingyu Wu Shan Zhu Li Li Shumin Wang yumei Lv Xin He Ming Zuo Chengyuan Liu Yang Pan Junfa Zhu Yongfu sun Yi Xie Hefei National Laboratory for Physical Sciences at Microscale National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China State Grid Anhui Electric Power Research Institute Hefei 230601China

Photocatalytic CH_(4) coupling into high-valued C_(2)H_(6) is highly attractive,whereas the photosynthetic rate,especially under oxygen-free system,is still unsatisfying.Here,we designed the negatively charged metal supported on metal oxide nanosheets to activate the inert C-H bond in CH_(4)and hence accelerate CH_(4) coupling performance.As an example,the synthetic Au/ZnO porous nanosheets exhibit the C_(2)H_(6) photosynthetic rate of 1,121.6μmol g^(-1)_(cat)h^(-1)and the CH_(4) conversion rate of 2,374.6μmol g^(-1)_(cat)h^(-1) under oxygen-free system,2 orders of magnitude higher than those of previously reported photocatalysts.By virtue of several in situ spectroscopic techniques,it is established that the generated Au^(δ-)and O^-species together polarized the C-H bond,while the Au^(δ-)and O^-species jointly stabilized the CH_(3) intermediates,which favored the coupling of CH_(3) intermediate to photosynthesize C_(2)H_(6) instead of overoxidation into CO_(x).Thus,the design of dual active species is beneficial for achieving high-efficient CH_(4)-to-C_(2)H_(6) photoconversion.

关键词： dual surface-active sites selective methane coupling ethane room temperature

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Resolving the lineage relationship between malignant cells and vascular cells in glioblastomas

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Protein & Cell 2023年第2期14卷 105-122页

作者： Fangyu Wang Xuan Liu Shaowen Li Chen Zhao yumei sun Kuan Tian Junbao Wang Wei Li Lichao Xu Jing Jing Juan Wang Sylvia MEvans Zhiqiang Li Ying Liu Yan Zhou Department of Neurosurgery Zhongnan hospital of Wuhan UniversityFrontier Science Center for Immunology and MetabolismMedical Research InstituteThe RNA InstituteCollege of Life SciencesWuhan UniversityWuhan 430071China Department of Neurology The Central Hospital of WuhanTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430014China Skaggs School of Pharmacy Department of MedicineDepartment of PharmacologyUniversity of California at San DiegoLa JollaCA 92093USA

Glioblastoma multiforme(GBM),a highly malignant and heterogeneous brain tumor,contains various types of tumor and non-tumor cells.Whether GBM cells can trans-differentiate into non-neural cell types,including mural cells or endothelial cells(ECs),to support tumor growth and invasion remains controversial.Here we generated two genetic GBM models de novo in immunocompetent mouse brains,mimicking essential pathological and molecular features of human GBMs.Lineage-tracing and transplantation studies demonstrated that,although blood vessels in GBM brains underwent drastic remodeling,evidence of trans-differentiation of GBM cells into vascular cells was barely detected.Intriguingly,GBM cells could promiscuously express markers for mural cells during gliomagenesis.Furthermore,single-cell RNA sequencing showed that patterns of copy number variations(CNVs)of mural cells and ECs were distinct from those of GBM cells,indicating discrete origins of GBM cells and vascular components.Importantly,single-cell CNV analysis of human GBM specimens also suggested that GBM cells and vascular cells are likely separate lineages.Rather than expansion owing to trans-differentiation,vascular cell expanded by proliferation during tumorigenesis.Therefore,cross-lineage trans-differentiation of GBM cells is very unlikely to occur during gliomagenesis.Our findings advance understanding of cell lineage dynamics during gliomagenesis,and have implications for targeted treatment of GBMs.

关键词： glioblastoma mural cells endothelial cells trans-differentiation lineage tracing single-cell sequencing copy number variation

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制造业数智化融合转型发展的关键要素、机理分析及评价指标研究

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中国科学院院刊 2024年第2期39卷 323-332页

作者：孙小强高秀云王玉梅青岛科技大学经济与管理学院青岛266061

制造业数智化融合转型已成为传统制造企业高质量发展的重要推动力。文章厘清国内外学者关于制造业数智化融合转型的主要研究脉络与关键问题,提炼制造业数智化融合转型发展的目标要素、主体要素及影响因素,依据系统动力学的系统反馈原理... 详细信息

制造业数智化融合转型已成为传统制造企业高质量发展的重要推动力。文章厘清国内外学者关于制造业数智化融合转型的主要研究脉络与关键问题,提炼制造业数智化融合转型发展的目标要素、主体要素及影响因素,依据系统动力学的系统反馈原理构建制造业数智化融合转型发展的动力网络模型,分析系统各要素之间作用机理;在此基础上,建立了一套科学的融合评价指标体系,为进一步研究制造业数智化融合转型发展问题提供理论参考。

关键词：制造业数智化融合转型关键要素机理分析评价指标

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中国中老年人群甘油三酯葡萄糖指数-腰围身高比与认知障碍关联的队列研究

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中华流行病学杂志 2024年第6期45卷 802-808页

作者：侯丁淳魏玥孙玉梅裴丽君陈功北京大学人口研究所北京100871 北京大学护理学院北京100191 北京大学中国老龄事业发展研究中心北京100871

目的分析中老年人中甘油三酯葡萄糖指数(TyG)-腰围身高比(WHtR)(TyG-WHtR)与认知障碍的关联。方法应用中国健康与养老追踪调查数据,以2011年和2015年的8946名中老年人为基线人群,构建队列数据库。应用Cox比例风险回归模型估计中老年人基... 详细信息

目的分析中老年人中甘油三酯葡萄糖指数(TyG)-腰围身高比(WHtR)(TyG-WHtR)与认知障碍的关联。方法应用中国健康与养老追踪调查数据,以2011年和2015年的8946名中老年人为基线人群,构建队列数据库。应用Cox比例风险回归模型估计中老年人基线TyG-WHtR不同水平与认知障碍风险的关联,并分别进行年龄和性别分层分析。结果8946名研究对象平均随访7.08人年,认知障碍发病密度为21.15/1000人年。与TyG-WHtR的Q1水平相比,其Q3和Q4水平分别使认知障碍风险增加32%(HR=1.32,95%CI:1.09~1.60)和47%(HR=1.47,95%CI:1.14~1.91)。趋势检验显示,认知障碍风险随TyG-WHtR水平升高而增加,且存在剂量-反应关系(P=0.001)。分层分析显示,45~59岁人群中,与TyG-WHtR的Q1水平相比,其Q3水平使认知障碍风险增加34%(HR=1.34,95%CI:1.02~1.78);≥60岁人群中,相比于TyG-WHtR的Q1水平,其Q3和Q4水平分别使认知障碍风险增加31%(HR=1.31,95%CI:1.01~1.72)和63%(HR=1.63,95%CI:1.15~2.31);男性中,TyG-WHtR水平与认知障碍风险无统计学关联(P>0.05);女性中,相比于TyG-WHtR的Q1水平,其Q4水平使认知障碍风险增加76%(HR=1.76,95%CI:1.26~2.46)。结论中老年人中较高的TyG-WHtR水平可增加认知障碍风险,且存在年龄、性别差异,早期的心血管健康管理和科学合理的体重管理对预防认知障碍具有重要意义。

关键词：认知障碍甘油三酯葡萄糖指数-腰围身高比队列研究中老年人

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数字经济下先进制造业与现代服务业的融合创新研究——机理、测量与对策

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经济社会体制比较 2024年第1期 61-73页

作者：王玉梅周一诺孙小强青岛科技大学经济与管理学院

现代服务业与先进制造业融合创新是数字经济下社会经济持续健康发展的重要保障。文章将融合创新过程划分为概念创新、研发创新、生产与制造创新、传送与商业化创新、反馈与提升创新5个环节,分析各环节影响因素及全过程融合创新机理;从... 详细信息

现代服务业与先进制造业融合创新是数字经济下社会经济持续健康发展的重要保障。文章将融合创新过程划分为概念创新、研发创新、生产与制造创新、传送与商业化创新、反馈与提升创新5个环节,分析各环节影响因素及全过程融合创新机理;从融合创新基础、融合创新环境、融合创新成果3个维度构建测量指标体系,运用熵值法和耦合协调模型,基于空间异质测量30省(市、自治区)的融合创新水平及融合创新内部的耦合协调性。研究结果显示,绝大多数省份的融合创新水平逐年稳步提升;各省份融合创新的耦合度高,协调度虽逐年提升但相对较低;各省份融合创新的失调大多表现为融合创新成果滞后型失调。文章认为应从加大融合创新基础投入、积极营造融合创新环境、加强融合创新成果转化能力和保障融合创新各环节协调推进等方面来提升中国先进制造业和现代服务业融合创新水平。

关键词：数字经济融合创新熵值法耦合协调度模型

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混合式教学中护理本科生学习方式的调查研究

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中华护理教育 2024年第5期21卷 557-562页

作者：孙玉梅周强叶铭惠孙宏玉赵国栋北京大学护理学院北京市100191 河北医科大学第三医院石家庄市050051 温州医科大学附属第一医院温州市325000 北京大学教育学院北京市100871

目的探讨混合式教学中护理学专业本科生深层学习与浅层学习的特点,为完善教学设计,提高教学效果提供参考。方法采用方便取样法,选取来自11所院校的混合式教学课程中的4180名学生,采用修订的两因素学习过程问卷(The Revise Two-factor St... 详细信息

目的探讨混合式教学中护理学专业本科生深层学习与浅层学习的特点,为完善教学设计,提高教学效果提供参考。方法采用方便取样法,选取来自11所院校的混合式教学课程中的4180名学生,采用修订的两因素学习过程问卷(The Revise Two-factor Study Process Questionnaire,R-SPQ-2F)对其学习方式进行调查。结果收集有效问卷3841份,学生的深层学习得分为33(30,38),浅层学习得分为28(23,31),其中深层学习得分以中、高水平为主(分别为53.8%、40.1%),而浅层学习以中、低水平为主(分别为53.7%、31.5%);中位数检验显示,不同院校、不同课程之间学生的深层学习与浅层学习得分差异有统计学意义(P0.05),与课程难度呈负相关(P0.05),与学习效果、满意度呈负相关(P<0.01)。结论混合式教学中护理学专业本科生更多采用的是深层学习,而浅层学习也有其积极意义;教师应注重学生的学习体验,激发其学习动机,促使其恰当采取不同的学习方式,以取得最佳的学习效果。

关键词：教育护理学士问卷调查深层学习混合式学习

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可分离式系线磁控胶囊内镜在肝硬化患者中的诊断价值

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西安交通大学学报（医学版） 2024年第3期45卷 449-454页

作者：孙焕焕卢桂芳任莉罗玉梅和水祥西安交通大学第一附属医院消化内科陕西西安710061

目的探讨可分离式系线磁控胶囊内镜(detachable string magnetically controlled capsule endoscopy,ds-MCE)在肝硬化患者中的诊断价值。方法筛选肝硬化患者分别进行胃镜(esophagogastroduodenoscopy,EGD)及ds-MCE检查,以传统EGD结果为标准,评估ds-MCE在肝硬化患者食管胃静脉曲张、高出血风险食管静脉曲张、门脉高压性胃病的准确性,门脉高压性肠病的检出情况以及患者舒适度。结果在2021年5月至2022年7月期间,总共53例患者成功入组,以EGD的检查结果为金标准,ds-MCE检出食管静脉曲张的敏感度为95.45%、特异度为100%、校正阳性预测值为100%、校正阴性预测值为95.65%,Kappa值为0.877(P<0.001);ds-MCE检出胃底静脉曲张的敏感度为93.94%、特异度为90%、校正阳性预测值为90.38%、校正阴性预测值为93.69%,Kappa值为0.839(P<0.001);ds-MCE检出门脉高压性胃病的敏感度为80%、特异度为90.70%、校正阳性预测值为89.59%、校正阴性预测值为81.93%,Kappa值为0.657(P<0.001);ds-MCE检出高出血风险食管静脉曲张的敏感度为76%、特异度为100%、校正阳性预测值为100%、校正阴性预测值为77.43%,Kappa值为0.770(P<0.001)。26.0%(13/50)肝硬化患者检出门脉高压性小肠疾病,主要表现为黏膜水肿、红斑和血管发育异常。ds-MCE舒适度评分[3(2,4)]相较于普通EGD舒适度评分[1(0,3)]更高(P<0.0001)。结论相较于传统EGD,ds-MCE在肝硬化食管胃底静脉曲张、门脉高压性胃病诊断方面准确度较高、安全可行、舒适度高,是一项极具潜力的可替代传统EGD筛查及监测肝硬化食管胃底静脉曲张的检查方法。

关键词：肝硬化胃镜(EGD) 可分离式系线磁控胶囊内镜(ds-MCE) 食管胃静脉曲张

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