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Spatial heterogeneity and compositional profiles of dissolved organic matter in farmland soils across China' Mainland

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Journal of Environmental Sciences 2024年第3期137卷 593-603页

作者： Bingjun Han liyuan chen Kang Xiao Yang Liu Dong Cao Lu Yu Yujun Li Shu Tao Wenxin Liu Key Laboratory for Earth Surface Processes College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Beijing Yanshan Earth Critical Zone National Research Station College of Resources and EnvironmentUniversity of Chinese Academy of SciencesBeijing 101408China Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental ScienceChinese Academy of SciencesBeijing 100085China

Dissolved organic matter(DOM) plays an essential role in many geochemical processes,however its complexity, chemical diversity, and molecular composition are poorly understood. Soil samples were collected from 500 vegetable fields in administrative regions of China' Mainland, of which 122 were selected for further investigation. DOM properties were characterized by three-dimensional excitation-emission matrix(3D-EEM) fuorescence spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry(FTICRMS)(field intensity is 15 Tesla). Our results indicated that the main constituents were UVA humic-like substances, humic-like substances, fulvic acid-like substances, and tyrosine-like substances. A total of 10,989 molecular formulae with a mass range of 100.04 to 799.59 Da were detected, covering the mass spectrometric information of the soil samples from 27 different regions. CHO and CHON molecules were dominant in DOM, whereas lignin, tannins,and aromatic substances served as the main components. The results of cluster analysis revealed that the soil properties in Jiangxi Province were considerably different from those in other regions. The key backgrounds of the DOM molecular characteristics in the vegetablefield soil samples across China' Mainland were provided at the molecular level, with large abundance and great variability.

关键词： Dissolved organic matter(DOM) Fourier transform ion cyclotron resonance mass(FTICR-MS) Excitation-emission matrix(EEM) Vegetable-field soils China' Mainland

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Efficient separation of C_(4) olefins using tantalum pentafluor oxide anion-pillared hybrid microporous material

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Chinese Journal of Chemical Engineering 2022年第2期35卷 49-54页

作者： Bin Gao Zhaoqiang Zhang Jianbo Hu Jiyu Cui liyuan chen Xili Cui Huabin Xing Key Laboratory of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China

With the increasing demand for synthetic rubber,the purification of 1,3-butadiene(C_(4)H_(6))is of great industrial significance.Herein,the successful removal of n-butene(n-C_(4)H_(8))and iso-butene(iso-C_(4)H_(8))from 1,3-butadiene(C_(4)H_(6))was realized by synthesizing a novel TaOF_(5)^(2-) anion-pillared ultramicroporous material TaOFFIVE-3-Ni(also referred to as ZU-96,TaOFFIVE=TaOF_(5)^(2-),3=pyrazine).Single-component adsorption isotherms show that TaOFFIVE-3-Ni can achieve the exclusion of n-C_(4)H_(8) and iso-C_(4)H_(8) in the low pressure region(0–30 kPa),and uptake C_(4)H_(6) with a high capacity of 92.78 cm^(3)·cm^(-3)(298 K and 100 kPa).The uptake ratio of C_(4)H_(6)/iso-C_(4)H_(8) on TaOFFIVE-3-Ni was 20.83(298 K and 100 kPa),which was the highest among the state-of-the-art adsorbents reported so far.With the rotation of anion and pyrazine ring,the pore size changes continuously,which makes smaller-size C_(4)H_(6) enter the channel while larger-size n-C_(4)H_(8) and iso-C_(4)H_(8) are completely blocked.The excellent breakthrough performance of TaOFFIVE-3-Ni shows great potential in industrial separation of C4 olefins.The specific adsorption binding sites within ZU-96 was further revealed through the modeling calculation.

关键词： Adsorptive separation C4 olefin 13-Butadiene Anion-pillared hybrid microporous material

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Occurrence of Aflatoxin B_(1),deoxynivalenol and zearalenone in feeds in China during 2018-2020

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Journal of Animal Science and Biotechnology 2022年第1期13卷 197-208页

作者： Ling Zhao Lei Zhang Zijian Xu Xingda Liu liyuan chen Jiefan Dai Niel Alexander Karrow Lvhui Sun Department of Animal Nutrition and Feed Science College of Animal Science and TechnologyHuazhong Agricultural UniversityWuhan 430070HubeiChina Guilin Li Yuan Grain and Oil Food Group Co. LtdGuilin 541001GuangxiChina Jiangsu Aomai Bio-Technology Co. LtdNanjing 211226China Department of Agriculture of Sichuan Province Chengdu 610041China Department of Animal Biosciences University of GuelphN1G2W1GuelphCanada

Background:The current study was conducted to investigate the individual and combined occurrence of aflatoxin B_(1)(AFB_(1)),deoxynivalenol(DON)and zearalenone(ZEN)in feeds from various Provinces of China during 2018 to 2020.A total of 3,507 feed samples,including 2,090 feed ingredients and 1,417 complete feed samples,were collected from different areas of China for mycotoxins analysis.Results:The individual contamination of AFB_(1),DON and ZEN were present in more than 81.9%,96.4% and 96.9% of feed samples,respectively,with average concentration ranges of AFB_(1) between 1.2-27.4μg/kg,DON between 458.0-1,925.4μg/kg and ZEN between 48.1-326.8μg/kg.Notably,0.9%,0.5% and 0.1% of feed ingredients,and 1.2-12.8%,0.9-2.9% and 0-8.9% of complete feeds for pigs,poultry and ruminants with AFB_(1),ZEN and DON that exceeded China’s safety standards,respectively.Moreover,more than 81.5%of feed ingredients and 95.7% of complete feeds were co-contaminated with various combinations of these mycotoxins.Conclusion:This study indicates that the feeds in China were universally contaminated with AFB_(1),DON and ZEN during the past 3 years.These findings highlight the significance of monitoring mycotoxin contaminant levels in the domestic animal feed,and the importance of carrying out feed administration and remediation strategies for mycotoxin control.

关键词： Aflatoxin B_(1) China Deoxynivalenol Feeds Zearalenone

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Identification of Arabidopsis MYB56 as a Nove Substrate for CRL3BPM E3 Ligases

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Molecular Plant 2015年第2期8卷 242-250页

作者： liyuan chen Anne Bernhardt JooHyun Lee Hanjo Hellmann School of Biological Sciences Washington State University Abelson 435 Pullman WA 99164-4236 USA Present address: Plant Gene Expression Center UC Berkeley Albany CA 94710 USA present address: Robert Koch Institut 13353 Berlin Germany

Controlled stability of proteins is a highly efficient mechanism to direct diverse processes in living cells. A key regulatory system for protein stability is given by the ubiquitin proteasome pathway, which uses E3 ligases to mark specific proteins for degradation. In this work, MYB56 is identified as a novel target of a CULLIN3 （CUL3）-based E3 ligase. Its stability depends on the presence of MATH-BTB/POZ （BPM） proteins, which function as substrate adaptors to the E3 ligase. Genetic studies have indicated that MYB56 is a negative regulator of flowering, while BPMs positively affect this developmental program. The interaction between BPMs and MYB56 occurs at the promoter of FLOWERING LOCUS T （FT）, a key regulator in initiating flowering in Arabidopsis, and results in instability of MYB56. Overall the work establishes MYB transcription factors as substrates of BPM proteins, and provides novel information on components that participate in controlling flowering time in plants.

关键词： CUL3 BPM MYB transcription factor E3 ligase flowering

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全球科学体系中的层级结构与开放结构——基于我国学术人才国际流动与知识生产的分析

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教育研究 2024年第4期45卷 96-108页

作者：陈丽媛荀渊上海交通大学教育学院上海200240 华东师范大学高等教育研究所上海200062

通过对全球科学体系相关理论进行梳理,全球科学体系可被视为一个层级结构与开放结构并存的双重结构体系。基于这一理论,提出国际流动以及流动到位于全球科学体系核心位置的国家对我国学者知识生产的影响逐渐减弱的研究假设。基于我国四... 详细信息

通过对全球科学体系相关理论进行梳理,全球科学体系可被视为一个层级结构与开放结构并存的双重结构体系。基于这一理论,提出国际流动以及流动到位于全球科学体系核心位置的国家对我国学者知识生产的影响逐渐减弱的研究假设。基于我国四所“双一流”建设高等学校的学术人才国际流动与发表数据,通过在回归模型中加入流动类型、地域与世代的交互项,从时间与空间两个维度验证假设。这预示着,全球科学体系中的核心—外围层级结构对我国学者知识生产的影响呈减弱趋势;随着全球科学体系开放性的增强,我国在全球科学体系中崛起、向核心位置转移的可能性逐渐增大。

关键词：全球科学体系国际学术流动知识生产

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Hierarchical porous MgBO_2(OH) microspheres: Hydrothermal synthesis,thermal decomposition, and application as adsorbents for Congo red removal

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Chinese Journal of Chemical Engineering 2018年第7期26卷 1561-1569页

作者： Panpan Sun liyuan chen Lin Xu Wancheng Zhu Department of Chemical Engineering Qufu Normal University

A facile eco-friendly hydrothermal route(180 °C, 12.0 h) has been developed for the first time to the uniform hierarchical porous MgBO_2(OH) microspheres without the aid of any organic additive, surfactant or template, by using the abundant MgCl_2·6 H_2 O, H_3BO_3 and NaOH as the raw materials. The as-obtained porous microspheres exhibit a specific surface area of 94.752 mg·g^(-1), pore volume of 0.814 cm3·g^(-1), and ca. 84.0% of which have a diameter of 2.25–3.40 μm. The thermal decomposition of the porous MgBO_2(OH) microspheres(650 °C,2.5 °C·min^(-1)) leads to the porous Mg_2B_2O_5 microspheres with well-retained morphology. When utilized as the adsorbents for the removal of CR from mimic waste water, the present porous MgBO_2(OH) microspheres exhibit satisfactory adsorption capacity, with the maximum adsorption capacity q^(-1) mof 309.1 mg·g, much higher than that derived from most of the referenced adsorbents. This opens a new window for the facile green hydrothermal synthesis of the hierarchical porous MgBO_2(OH) microspheres, and extends the potential application of the 3 D hierarchical porous metal borates as high-efficiency adsorbents for organic dyes removal.

关键词：吸附物热分解多孔热水合成移动刚果红表面活化剂

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Emission factors of particulate matter, CO and CO_2 in the pyrolytic processing of typical electronic wastes

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Journal of Environmental Sciences 2019年第7期31卷 93-101页

作者： liyuan chen Chuanyang Cai Shuangyu Yu Yu Liu Shu Tao Wenxin Liu Key Laboratory for Earth Surface Processes College of Urban and Environmental Sciences Peking University

A self-designed experimental device was employed to simulate the pyrolytic dismantling process of selected electronic wastes(E-wastes), including printed wiring boards(PWBs)and plastic casings. The generated particulate matter(PM) of different particle sizes, carbon monoxide(CO) and carbon dioxide(CO_2) were determined, and the corresponding emission factors(EFs) were estimated. Finer particles with particle sizes of 0.4–2.1 μm accounted for78.9% and 89.3% of PM emitted by the pyrolytic processing of PWBs and plastic casings,respectively, and the corresponding EFs were 9.68 ± 4.81 and 18.49 ± 7.2 g/kg, respectively.The EFs of CO and CO_2 from PWBs and plastic casings were 55.9 ± 26.9 and 1182 ± 439 g/kg,and 133.6 ± 34.6 and 2827 ± 276 g/kg, respectively. Compared with other emission sources,such as coal, biomass, and traffic exhaust, the EFs of E-wastes were relatively higher,especially for PM. There were significant positive correlations(p < 0.05) of the initial contents of carbon and nitrogen in PWBs with the related EFs of PM, CO, and CO_2, while the correlations for plastic casings were insignificant. The EFs of CO of PWBs were significantly positively correlated with the corresponding EFs of PM and the parent polycyclic aromatic hydrocarbons(PAHs); however, the same result was not observed for plastic casings.

关键词： Pyrolytic processing of electronic-wastes Particulate matter CO CO2 Emission factor

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Prim-O-glucosylcimifugin ameliorates aging-impaired endogenous tendon regeneration by rejuvenating senescent tendon stem/progenitor cells

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Bone Research 2023年第4期11卷 784-802页

作者： Yu Wang Shanshan Jin Dan Luo Danqing He Min Yu Lisha Zhu Zixin Li liyuan chen chengye Ding Xiaolan Wu Tianhao Wu Weiran Huang Xuelin Zhao Meng Xu Zhengwei Xie Yan Liu Laboratory of Biomimetic Nanomaterials Department of OrthodonticsPeking University School and Hospital of Stomatology&National Center for Stomatology&National Clinical Research Center for Oral Diseases&National Engineering Laboratory for Digital and Material Technology of Stomatology&Beijing Key Laboratory of Digital Stomatology&Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health&NMPA Key Laboratory for Dental Materials&Translational Research Center for Orocraniofacial Stem Cells and Systemic HealthBeijing 100081China CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China Peking University International Cancer Institute Health Science CenterPeking UniversityBeijing 100083China Department of Orthopedics the Fourth Medical Center of PLA General HospitalBeijing 100048China

Adult tendon stem/progenitor cells(TSPCs)are essential for tendon maintenance,regeneration,and repair,yet they become susceptible to senescence with age,impairing the self-healing capacity of tendons.In this study,we employ a recently developed deep-learning-based efficacy prediction system to screen potential stemness-promoting and senescence-inhibiting drugs from natural products using the transcriptional signatures of stemness.The top-ranked candidate,prim-O-glucosylcimifugin(POG),a saposhnikovia root extract,could ameliorate TPSC senescent phenotypes caused by long-term passage and natural aging in rats and humans,as well as restore the self-renewal and proliferative capacities and tenogenic potential of aged TSPCs.In vivo,the systematic administration of POG or the local delivery of POG nanoparticles functionally rescued endogenous tendon regeneration and repair in aged rats to levels similar to those of normal animals.Mechanistically,POG protects TSPCs against functional impairment during both passage-induced and natural aging by simultaneously suppressing nuclear factor-κB and decreasing mTOR signaling with the induction of autophagy.Thus,the strategy of pharmacological intervention with the deep learning-predicted compound POG could rejuvenate aged TSPCs and improve the regenerative capacity of aged tendons.

关键词： tendon endogenous progenitor

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MYB106 is a negative regulator and a substrate for CRL3^(BPM) E3 ligase in regulating flowering time in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2021年第6期63卷 1104-1119页

作者： Liu Hong Fangfang Niu Youshun Lin Shuang Wang liyuan chen Liwen Jiang Center for Cell&Developmental Biology State Key Laboratory of AgrobiotechnologySchool of Life SciencesThe Chinese University of Hong KongShatinNew TerritoriesHong KongChina Shenzhen Research Institute The Chinese University of Hong KongShenzhen 518057China Shenzhen Technology University Shenzhen 518000China School of Chemical Biology&Biotechnology Peking University Shenzhen Graduate SchoolNanshan DistrictShenzhen 518055China

Flowering time is crucial for successful reproduction in plants, the onset and progression of which are strictly controlled. However, flowering time is a complex and environmentally responsive history trait and the underlying mechanisms still need to be fully characterized. Post-translational regulation of the activities of transcription factors(TFs) is a dynamic and essential mechanism for plant growth and development. CRL3 BPME3 ligase is a CULLIN3-based E3 ligase involved in orchestrating protein stability via the ubiquitin proteasome pathway. Our study shows that the mutation of MYB106 induced early flowering phenotype while over-expression of MYB106 delayed Arabidopsis flowering. Transcriptome analysis of myb106 mutants reveals 257 differentially expressed genes between wild type and myb106-1 mutants, including Flowering Locus T(FT) which is related to flowering time. Moreover, in vitro electrophoretic mobility shift assays(EMSA), in vivo chromatin immunoprecipitation quantitative polymerase chain reaction(ChIP-q PCR) assays and dual luciferase assays demonstrate that MYB106 directly binds to the promoter of FT to suppress its expression. Furthermore, we confirm that MYB106 interacts with BPM proteins which are further identified by CRL3 BPME3 ligases as the substrate. Taken together, we have identified MYB106 as a negative regulator in the control of flowering time and a new substrate for CRL3 BPM E3 ligases in Arabidopsis.

关键词： flowering time MYB transcription factor E3 ligase CUL3~(BPM)

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Improved dissolution and anti-inflammatory effect of ibuprofen by solid dispersion

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Frontiers of Medicine 2012年第2期6卷 195-203页

作者： liyuan chen Qifeng Dang chengsheng Liu Jun chen Lei Song Xiguang chen College of Marine Life Sciences Ocean University of ChinaQingdao 266003China Department of Surgery the Commercial Staff&Workers Hospital of QingdaoQingdao 266011China

The purpose of this study was to improve the dissolution rate and anti-inflammatory effect of ibuprofen by a solid dispersion(SD)method.Initial screening was developed based on drug solubility in carriers in the liquid state to select a suitable water-soluble carrier system for the preparation of SDs.The dissolution of ibuprofen in urea was higher than in PEG4000 or mannitol.Thus,urea was selected as the carrier for the preparation of SDs.SDs were characterized in terms of dissolution,differential scanning calorimetry(DSC),X-ray diffraction(XRD),scanning electron microscopy(SEM),and Fourier transform infrared(FTIR)spectroscopy.Solid dispersionbased(SDBT)and conventional(CT)tablets were prepared by the wet granulation method.The antiinflammatory effect of SDBT was evaluated using the mouse ear edema test with xylene.In vitro release results indicated that the ibuprofen dissolution rate was improved by the SD.SD characterization results suggested that ibuprofen partly precipitates in crystalline and amorphous forms after SD preparation and that ibuprofen and urea do not interact.SDBT displayed more significant anti-inflammatory effects than CT.The dissolution rate and anti-inflammatory effect of ibuprofen were significantly enhanced by the ibuprofen-urea SD.

关键词： ibuprofen solid dispersion physical mixture dissolution anti-inflammatory effect

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