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Identification and screening of cardiac glycosides in Streptocaulon griffithii using an integrated data mining strategy based on high resolution mass spectrometry

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Chinese Journal of Natural Medicines 2018年第7期16卷 546-560页

作者： zhu xiao-Yu LIU Jia-zhuo DONG Zhen-Huan FENG Feng LIU Wen-Yuan Key Laboratory of Drug Quality Control and Pharmacovigilance Ministry of Education China Pharmaceutical University Key Laboratory of Biomedical Functional Materials China Pharmaceutical University

The present study was designed to develop a practical strategy to tackle the problem of lacking standard compounds and limited references for identifying structure-related compounds in Streptocaulon griffithii Hook. f., especially those in trace concentrations, with a focus on antitumor activity. The cardiac glycosides(CGs)-enriched part was determined using in vitro bioactive assays in three cancer cell lines and then isolated using macroporous resins. The MS and MS/MS data were acquired using a high performance liquid chromatography coupled with hybrid quadrupole-time of flight(HPLC-Q-TOF-MS) system. To acquire data of trace compound in the extract, a multiple segment program was applied to modify the HPLC-Q-TOF-MS method. A mass defect filter(MDF) approach was employed to make a primary MS data filtration. Utilizing a MATLAB program, the redundant peaks obtained by imprecise MDF template calculated with limited references were excluded by fragment ion classification, which was based on the ion occurrence number in the MDF-filtered total ion chromatograms(TIC). Additionally, the complete cleavage pathways of CG aglycones were proposed to assist the structural identification of 29 common fragment ions(CFIs, ion occurrence number ≥ 5) and diagnostic fragment ions(DFIs, ion occurrence number < 5). As a result, 30 CGs were filtered out from the MDF results, among which 23 were identified. This newly developed strategy may provide a rapid and effective tool for identifying structure-related compounds in herbal medicines.

关键词： Streptocaulongriffithii Cardiac glycosides Mass defect filter HPLC-Q-TOF-MS

Optimizing loading path and die linetype of large length-to-diameter ratio metal stator screw lining hydroforming

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Journal of Central South University 2015年第1期22卷 224-231页

作者：祝效华石昌帅童华 Mechatronic Engineering College Southwest Petroleum University

In order to meet the high temperature environment requirement of deep and superdeep well exploitation, a technology of large length-to-diameter ratio metal stator screw lining meshing with rotor is presented. Based on the elastic-plasticity theory, and under the consideration of the effect of tube size, material mechanical parameters, friction coefficient and loading paths, the external pressure plastic forming mechanical model of metal stator screw lining is established, to study the optimal loading path of metal stator lining tube hydroforming process. The results show that wall thickness reduction of the external pressure tube hydroforming(THF) is about 4%, and three evaluation criteria of metal stator screw lining forming quality are presented: fillet stick mold coefficient, thickness relative error and forming quality coefficient. The smaller the three criteria are, the better the forming quality *** indicator has a trend of increase with the loading rate reducing, and the adjustment laws of die arc transition zone equidistance profile curve are acquired for improving tube forming quality. Hence, the research results prove the feasibility of external pressure THF used for processing high-accuracy large length-to-diameter ratio metal stator screw lining, and provide theoretical basis for designing new kind of stator structure which has better performance and longer service life.

关键词： tube hydroforming loading path large length-to-diameter ratio metal stator lining simulation

Modified variational iteration method for an El Nio Southern Oscillation delayed oscillator

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Chinese Physics B 2012年第2期21卷 51-55页

作者： Cao xiao-Qun Song Jun-Qiang zhu xiao-Qian Zhang Li-Lun Zhang Wei-Min Zhao Jun School of Computer Science National University of Defense TechnologyChangsha 410073China

This paper studies a delayed air-sea coupled oscillator describing the physical mechanism of El Nino Southern Oscillation. The approximate expansions of the delayed differential equation＇s solution are obtained successfully by the modified variational iteration method. The numerical results illustrate the effectiveness and correctness of the method by comparing with the exact solution of the reduced model.

关键词： air sea coupling nonlinear oscillator modified variational iteration method delayeddifferential equation

Critical roles of FTO-mediated mRNA m6A demethylation in regulating adipogenesis and lipid metabolism: Implications in lipid metabolic disorders

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Genes & Diseases 2022年第1期9卷 51-61页

作者： Zhou Yang Guang-li Yu xiao zhu Tian-hong Peng Yun-cheng Lv Clinical Anatomy&Reproductive Medicine Application Institute Hengyang Medical CollegeUniversity of South ChinaHengyangHunan 421001PR China Guangxi Key Laboratory of Diabetic Systems Medicine Guilin Medical UniversityGuilinGuangxi 541199PR China

The goal this review is to clarify the effects of the fat mass and obesity-associated protein (FTO) in lipid metabolism regulation and related underlying mechanisms through the FTO-mediated demethylation of m6A modification. FTO catalyzes the demethylation of m6A to alter the processing, maturation and translation of the mRNAs of lipid-related genes. FTO overexpression in the liver promotes lipogenesis and lipid droplet (LD) enlargement and suppresses CPT-1–mediated fatty acid oxidation via the SREBP1c pathway, promoting excessive lipid storage and nonalcoholic fatty liver diseases (NAFLD). FTO enhances preadipocyte differentiation through the C/EBPβ pathway, and facilitates adipogenesis and fat deposition by altering the alternative splicing of RUNX1T1, the expression of PPARγ and ANGPTL4, and the phosphorylation of PLIN1, whereas it inhibits lipolysis by inhibiting IRX3 expression and the leptin pathway, causing the occurrence and development of obesity. Suppression of the PPARβ/δ and AMPK pathways by FTO-mediated m6A demethylation damages lipid utilization in skeletal muscles, leading to the occurrence of diabetic hyperlipidemia. m6A demethylation by FTO inhibits macrophage lipid influx by downregulating PPARγ protein expression and accelerates cholesterol efflux by phosphorylating AMPK, thereby impeding foam cell formation and atherosclerosis development. In summary, FTO-mediated m6A demethylation modulates the expression of lipid-related genes to regulate lipid metabolism and lipid disorder diseases.

关键词： Adipose tissue FTO Lipid disorder diseases Lipid metabolism Liver Skeletal muscle

Simulation of isothermal precision extrusion of NiTi shape memory alloy pipe coupling by combining finite element method with cellular automaton

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Journal of Central South University 2017年第3期24卷 506-514页

作者： ZHANG Yan-qiu JIANG Shu-yong ZHAO Ya-nan zhu xiao-ming College of Mechanical and Electrical Engineering Harbin Engineering University Harbin 150001 China

In order to present the microstructures of dynamic recrystallization(DRX) in different deformation zones of hot extruded NiTi shape memory alloy(SMA) pipe coupling,a simulation approach combining finite element method(FEM) with cellular automaton(CA) was developed and the relationship between the macroscopic field variables and the microscopic internal variables was *** results show that there exists a great distinction among the microstructures in different zones of pipe coupling because deformation histories of these regions are *** plastic deformation may result in fine recrystallized grains,whereas the recrystallized grains may grow very substantially if there is a rigid translation during the deformation,even if the final plastic strain is very *** a consequence,the deformation history has a significant influence on the evolution path of the DRX as well as the final microstructures of the DRX,including the morphology,the mean grain size and the recrystallization fraction.

关键词： shape memory alloy dynamic recrystallization cellular automaton finite element method extrusion

Spatially-explicit quantitative relationship for a potential PES mechanism:Cascade hydropower development in Yarlung Zangbo River Basin, China

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Journal of Mountain Science 2022年第4期19卷 925-944页

作者： zhu xiao-kang FU Bin Ramon Felipe BICUDO DA SILVA GUO Ying-man QIN Chan-yuan FENG Ting YU Hai-bing xiao Kuang Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Xihua University Chengdu 610039China Sichuan Provincial Chengdu Ecological and Environmental Monitoring Center Station Chengdu 610041China Center for Systems Integration and Sustainability Department of Fisheries and WildlifeMichigan State UniversityEast Lansing MI 48823USA Center for Environmental Studies and Research State University of CampinasCampinas 13083-867Brazil

Payment for ecosystem services(PES) is of great importance for the sustainable development of mountain areas, key hotspot regions for the provisioning of ecosystem services. At present, PES researches mainly focus on forest protection, carbon sink trading, and water protection. As an important industry in mountainous areas, cascade hydropower development has generated substantial economic benefits accompanied by social and ecological impacts. However, efficient PES mechanisms to deal with hydropower generation in mountain areas are still unavailable. Therefore, the lacking of PES in mountain systems limits the development of those areas, and compromise the sustainability of hydropower development. The critical reason lies in the lack of a scientific method that can quantitatively analyze the relationship of hydropower stations with a geographical scope at county level(i.e., quantifying the water yield service provided by each county within the cascade hydropower development basin), and with different hydropower enterprises. We use the Yarlung Zangbo River Basin of China as case study area, one of the major hydropower development basins in China. First, we used Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST) model to map water yield service. Then, we calculated the value of water yield service by relating the water yield to the gross output value of hydropower stations. We revealed the relationship(e.g., hydropower stations and identified counties) between the payers and the payees of ecosystem services through mapping and quantifying the provisioning regions in the supply of water yield service and the users(hydropower enterprises). Finally, we discussed the current situation of benefit distribution in cascade hydropower development basin based on the supply and use of the water yield service. The results showed that 1) the spatial distribution of the value of water yield service is uneven: the upper reaches are highvalue areas;the eastern region is

关键词： Water yield service Relationship Hydropower development InVEST model QinghaiTibet Plateau

Systematic investigation of SO_(2) adsorption and desorption by porous powdered activated coke:Interaction between adsorption temperature and desorption energy consumption

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Chinese Journal of Chemical Engineering 2022年第8期35卷 140-148页

作者： Jun Li Liqiang Zhang xiao zhu Mengze Zhang Tai Feng Xiqiang Zhao Tao Wang Zhanlong Song Chunyuan Ma National Engineering Laboratory for Reducing Emissions from Coal Combustion Engineering Research Center of Environmental Thermal Technology of Ministry of EducationShandong Key Laboratory of Energy Carbon Reduction and Resource UtilizationSchool of Energy and Power EngineeringShandong UniversityJinan 250061China College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao 266590China

Porous carbon materials have been widely used for the removal of SO_(2) from flue *** main objective of this work is to clarify the effects of adsorption temperature on SO_(2) adsorption and desorption energy ***-based porous powdered activated coke(PPAC)prepared in the drop-tube reactor was used in this *** N_(2) adsorption measurements and Fourier transform infrared spectrometer analysis show that PPAC exhibits a developed pore structure and rich functional *** experimental results show that with a decrease in adsorption temperature in the range of 50–150℃,the adsorption capacity of SO_(2) increases linearly;meanwhile,the adsorption capacity of H_(2)O increases,resulting in the increase in desorption energy consumption per unit mass of *** processes of SO_(2) and H_(2)O desorption were determined by the temperature-programmed desorption test,and the desorption energies for each species were *** the energy consumption per unit of desorption and the total amount of adsorbent,the optimal adsorption temperature yielding the minimum total energy consumption of regeneration is *** study systematically demonstrates the effect of adsorption temperature on the adsorption–desorption process,providing a basis for energy saving and emission reduction in desulfurization system design.

关键词： Activated coke SO2 adsorption Desorption energy consumption Optimal adsorption temperature

Meltblown fabric vs nanofiber membrane, which is better for fabricating personal protective equipments

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Chinese Journal of Chemical Engineering 2021年第8期34卷 1-9页

作者： Junwei Wu Hongjia Zhou Jingyi Zhou xiao zhu Bowen Zhang Shasha Feng Zhaoxiang Zhong Lingxue Kong Weihong Xing State Key Laboratory of Materials-Oriented Chemical Engineering National Engineering Research Center for Special Separation MembraneNanjing Tech UniversityNanjing 210009China Jiangsu Jiulang High-Tech Co. LtdNanjing 210009China Department of Material and Chemical Engineering Soochow UniversitySuzhou 215006China Institute for Frontier Materials Deakin UniversityGeelongVictoria 3216Australia

The coronavirus disease 2019(COVID-19)pandemic has led to a great demand on the personal protection products such as reusable *** a key raw material for masks,meltblown fabrics play an important role in rejection of ***,the electrostatic dominated aerosol rejection mechanism of meltblown fabrics prevents the mask from maintaining the desired protective effect after the static charge ***,novel reusable masks with high aerosols rejection efficiency were fabricated by the introduction of spider-web bionic nanofiber membrane(nano cobweb-biomimetic membrane).The reuse stability of meltblown and nanofiber membrane mask was separately evaluated by infiltrating water,75%alcohol solution,and exposing under ultraviolet(UV)*** the water immersion test,the filtration efficiency of meltblown mask was decreased to about 79%,while the nanofiber membrane was maintained at 99%.The same phenomenon could be observed after the 75%alcohol treatment,a high filtration efficiency of 99%was maintained in nanofiber membrane,but obvious negative effect was observed in meltblown mask,which decreased to about 50%.In addition,after long-term expose under UV light,no filtration efficiency decrease was observed in nanofiber membrane,which provide a suitable way to disinfect the potential carried *** work successfully achieved the daily disinfection and reuse of masks,which effectively alleviate the shortage of masks during this special period.

关键词： Filtration efficiency Meltblown fabrics Nano cobweb-biomimetic membrane Reusable mask

Dynamics of microbial diversity during the composting of agricultural straw

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Journal of Integrative Agriculture 2021年第5期20卷 1121-1136页

作者： CHANG Hui-qing zhu xiao-hui WU Jie GUO Da-yong ZHANG Lian-he FENG Yao Henan University of Science and Technology Luoyang 471023P.R.China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/Key Laboratory of Plant Nutrition and FertilizerMinistry of Agriculture and Rural AffairsBeijing 100081P.R.China

The dynamic changes in microbial diversity during the aerobic composting of agricultural crop straw with additives were evaluated using high-throughput sequencing at four phases of composting(mesophilic,thermophilic,cooling and maturation phases).In addition,the physicochemical parameters of the composting system were determined in this *** fermentation time of the thermophilic period was prolonged with the addition of urea or urea combined with a microbial *** ratio of C/N and germination index variation indicated that the additives were favorable for composting,because the additives directly changed the physicochemical properties of the compost and had effects on the diversity and abundance of bacteria and *** abundance of operational taxonomic units(OTUs),diversity index(Shannon)and richness index(Chao1)of fungi and bacteria were found to significantly increase when urea+microbial agents were added to straw in the thermophilic *** relative abundance of the predominant bacteria and fungi at the phylum and genus levels differed during different composting *** abundance of the phyla Firmicutes and Proteobacteria declined in the order of treatments SNW>SN>S(S is straw only compost;SN is straw+5 kg t^(–1) urea compost;and SNW is straw+5 kg t^(–1) urea+1 kg t^(–1) microbial agent compost)in the thermophilic *** abundance of the genera Staphylococcus,Bacillus and Thermobifida followed the same order in the mesophilic *** accounted for more than 92%of the total fungal *** the progression of the composting process,the abundance of Ascomycota decreased *** abundance of Ascomycota followed the order of S>SN>SNW during the thermophilic *** abundance of Aspergillus accounted for 4–59%of the total abundance of fungi and increased during the first two sampling *** abundance followed the order of SNW>SN>***,principal component analysis(PCA)revealed that the community compositi

关键词： crop straws microbial diversity community composition dynamic characteristics high-throughput sequencing