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Microbial transformations of bile acids and their receptors in the regulation of metabolic dysfunction-associated steatotic liver disease

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Liver Research 2023年第3期7卷 165-176页

作者： Yuhua Gao jun Lin Chuan Ye Siqi guo Changtao Jiang Department of Physiology and Pathophysiology School of Basic Medical SciencesPeking Universityand the Key Laboratory of Molecular Cardiovascular Science(Peking University)Ministry of EducationBeijingChina Center of Basic Medical Research Institute of Medical Innovation and ResearchThird HospitalPeking UniversityBeijingChina Center for Obesity and Metabolic Disease Research School of Basic Medical SciencesPeking UniversityBeijingChina

Bile acids(BAs)play important roles in the digestion of dietary fats and molecular signal transduction,and modulation of the BA composition usually affects the progression of metabolic *** the liver produces primary BAs,the gut microbiota modifies these products into various forms that greatly increase their diversity and biological ***,BAs can regulate their own metabolism and transport as well as other key aspects of metabolic processes via dedicated BA *** of BA transport and homeostasis leads to the progression of liver diseases,including metabolic dysfunction-associated steatotic liver disease(MASLD)and hepatocellular carcinoma(HCC).Here,we summarize the microbial transformations of BAs and their downstream signaling in the development of metabolic diseases and present new insights into novel therapeutic strategies targeting BA pathways that may contribute to these diseases.

关键词： Bile acids(BAs) Gut microbiota Metabolic dysfunction-associated steatotic liver disease(MASLD) Metabolic dysfunction-associated steatohepatitis(MASH) Hepatocellular carcinoma(HCC) Farnesoid X receptor(FXR) G protein-coupled bile acid receptor 1(TGR5)

Gravitational Deflection of Massive Particles by a Schwarzschild Black Hole in Radiation Gauge

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Communications in Theoretical Physics 2019年第10期71卷 1219-1226页

作者： Zong-Hai Li xia Zhou Wei-jun Li Guan-Sheng He School of Physical Science and Technology Southwest Jiaotong UniversityChengdu610031China Physics and Space Science College China West Normal UniversityNanchong637009China School of Mathematics and Physics University of South ChinaHengyang421001China

The exact metric of a Schwarzschild black hole in the true radiation gauge was recently reported. In this work, we base on this gravity and calculate the gravitational deflection of relativistic massive particles up to the fourth post-Minkowskian order. It is found that the result is consistent with the previous formulations for both the case of dropping the fourth-order contribution and the case of light deflection. Our result might be helpful for future high-accuracy observations.

关键词： gravitational deflection relativistic massive particles radiation gauge Schwarzschild black hole

表面施胶水性聚氨酯对箱纸板耐折性能的影响及作用机理

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中国造纸 2024年第4期43卷 146-154页

作者：马朴杨云艳马玉芹徐芳吴闻达郭丽芳黄军济宁南天农科化工有限公司山东济宁272200 南京田家炳高级中学江苏南京210000 南京鼎兆新材料技术研发有限公司江苏南京210000

通过表面施胶不同特性(非离子型和阳离子型)的水性聚氨酯(WPU),研究了WPU施胶对箱纸板耐折性能的影响及作用机理。结果表明,WPU成膜性能、纸张结构和施胶工艺,对箱纸板耐折性能均有显著影响。非离子型的WPU-A膜强韧,拉伸强度达7.11 MPa... 详细信息

通过表面施胶不同特性(非离子型和阳离子型)的水性聚氨酯(WPU),研究了WPU施胶对箱纸板耐折性能的影响及作用机理。结果表明,WPU成膜性能、纸张结构和施胶工艺,对箱纸板耐折性能均有显著影响。非离子型的WPU-A膜强韧,拉伸强度达7.11 MPa;阳离子型的WPU-B膜中软易黏,拉伸强度很低。对于含水量低的纸张,在同等实验条件下,成膜柔韧、拉伸强度高的WPU施胶,有利于提高箱纸板的耐折性能。纸张结构越疏松,WPU施胶对其耐折度的提升幅度越大,且对于结构紧实的纸张,WPU膜强度与纸张强度显示出协同作用。对比4种不同施胶工艺所得箱纸板,干燥后双面施胶箱纸板的耐折性能提升效果最佳。

关键词：表面施胶剂水性聚氨酯箱纸板耐折性能

硒砂瓜根系不同生态位细菌群落多样性及结构分析

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南方农业学报 2024年第4期55卷 985-995页

作者：朱滕滕岳思君谢志鹏王国琴郑蕊苏建宇宁夏大学生命科学学院/宁夏大学西部特色生物资源保护与利用教育部重点实验室宁夏银川750021

【目的】分析硒砂瓜根系不同生态位细菌群落结构及多样性,为了解硒砂瓜根系微生物组成规律,挖掘微生物资源,维持硒砂瓜根系土壤健康及微生物生态系统稳定提供理论参考。【方法】采用五点取样法采集根围、根际、根表和根内4个生态位土壤... 详细信息

【目的】分析硒砂瓜根系不同生态位细菌群落结构及多样性,为了解硒砂瓜根系微生物组成规律,挖掘微生物资源,维持硒砂瓜根系土壤健康及微生物生态系统稳定提供理论参考。【方法】采用五点取样法采集根围、根际、根表和根内4个生态位土壤样品,分别标记为SRW、SRJ、SRB和SRN,通过使用Illumina Miseq测序平台对硒砂瓜根系不同生态位细菌群落进行解析,探究硒砂瓜细菌群落Alpha多样性指数,包括Sobs、Shannon、Simpson、Chao1和ACE指数,比较各生态位及内生菌与硒砂瓜根系其他生态位在门和属分类水平上的细菌物种差异,并进行主坐标分析(PCoA)及溯源分析。【结果】土壤中(SRW、SRJ及SRB)细菌群落Sobs、Shannon、ACE和Chao1指数均显著高于内生菌群落(SRN)(PSRW>SRB>SRN,丰富度即ACE和Chao1指数排序为SRW>SRJ>SRB>SRN。硒砂瓜根系不同生态位细菌类群的优势门均为变形菌门(Proteobacteria)和放线菌门(Actinobacteriota),各生态位变形菌门占比59.59%~84.62%,4个生态位的优势属均为根瘤菌属(AllorhizobiumNeorhizobium-Pararhizobium-Rhizobium)、克雷伯氏菌属(Klebsiella)和固氮菌属(Azotobacter),根瘤菌属占比5.48%~15.68%。PCoA结果显示,硒砂瓜根系不同生态位的群落结构存在显著差异(R2=0.6651,P=0.001)。根系各生态位相对丰度前15的物种中,10个细菌门和8个细菌属的相对丰度存在显著差异。内生菌与硒砂瓜根系其他生态位相对丰度前15的物种中,8个细菌门和5个细菌属的相对丰度存在显著差异。溯源分析结果发现根际细菌群落中有55.70%来源于根围细菌,根表细菌群落中有65.75%来源于根际细菌,根内细菌群落中有90.75%来源于根表细菌,表明硒砂瓜根系不同生态位细菌群落来源之间存在一定相关性。【结论】宁夏硒砂瓜根系不同生态位细菌群落组成丰富,相对丰度有差异且细菌群落来源具有一定相关性,不同生态位对细菌群落具有选择及过滤作用。

关键词：硒砂瓜根系细菌群落生态位多样性群落结构

基于失效物理的风电机组多故障可靠性建模方法

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科学技术与工程 2024年第15期24卷 6281-6289页

作者：葛新宇毕俊喜王妍王柳璎王国富焦佳明内蒙古工业大学机械工程学院呼和浩特010051 内蒙古工业大学航空学院呼和浩特010051 风能太阳能利用技术教育部重点实验室(内蒙古工业大学) 呼和浩特010051

风电机组由于功能结构复杂且工作环境恶劣导致其退化状态呈现多样性特点,失效形式往往是多种故障耦合作用的结果,因此单独采用某一变量的性能退化过程作为评估风电机组寿命及可靠性模型是不全面的。为了更精确反映系统内部和外部性能指... 详细信息

风电机组由于功能结构复杂且工作环境恶劣导致其退化状态呈现多样性特点,失效形式往往是多种故障耦合作用的结果,因此单独采用某一变量的性能退化过程作为评估风电机组寿命及可靠性模型是不全面的。为了更精确反映系统内部和外部性能指标的相关性,提出了一种基于失效物理的风电机组多故障可靠性建模方法。首先分析了风电机组多应力耦合下的工作环境和故障特性,通过基于失效物理的可靠性仿真分析方法获得寿命分布函数,并将其作为边缘分布函数;其次在考虑故障模式相关性时,引入两阶段估计法对Copula函数的模型进行参数估计。通过对比不同类型Copula函数的秩相关系数和平方欧氏距离,确定最优Copula函数。最后利用Skla定理和逐步分析的思想,建立多故障模式耦合下的简化风电机组可靠性模型。结果表明,考虑可靠性指标相关性时得到的可靠性结果更加合理,同时该方法避免了风电机组寿命预测和可靠性评估的保守估计,具有较好的实用性和可操作性。

关键词：风电机组失效物理故障相关性 Copula函数可靠性建模

A Case Study of Impact of FY-2C Satellite Data in Cloud Analysis to Improve Short-Range Precipitation Forecast

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Atmospheric and Oceanic Science Letters 2014年第6期7卷 527-533页

作者： LIU Rui-xia CHEN Hong-Bin CHEN De-Hui XU guo-Qiang Key Laboratory of Radiometric Calibration and Validation for Environmental Satellite National Satellite Meteorological CenterChina Meteorological Administration Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric PhysicsChinese Academy of Sciences Numerical Prediction Center China Meteorological Administration

Chinese FengYun-2C(FY-2C) satellite data were combined into the Local Analysis and Prediction System(LAPS) model to obtain three-dimensional cloud parameters and rain content. These parameters analyzed by LAPS were used to initialize the Global/Regional Assimilation and Prediction System model(GRAPES) in China to predict precipitation in a rainstorm case in the country. Three prediction experiments were conducted and were used to investigate the impacts of FY-2C satellite data on cloud analysis of LAPS and on short range precipitation forecasts. In the first experiment, the initial cloud fields was zero value. In the second, the initial cloud fields were cloud liquid water, cloud ice, and rain content derived from LAPS without combining the satellite data. In the third experiment, the initial cloud fields were cloud liquid water, cloud ice, and rain content derived from LAPS including satellite data. The results indicated that the FY-2C satellite data combination in LAPS can show more realistic cloud distributions, and the model simulation for precipitation in 1–6 h had certain improvements over that when satellite data and complex cloud analysis were not applied.

关键词： FY-2C satellite data cloud analysis precipitation forecast impact study

The chromosome-level reference genome of Coptis chinensis provides insights into genomic evolution and berberine biosynthesis

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Horticulture Research 2021年第1期8卷 1632-1642页

作者： Da-xia Chen Yuan Pan Yu Wang Yan-Ze Cui Ying-jun Zhang Rang-yu Mo xiao-li Wu jun Tan Jian Zhang Lian-an guo xiao Zhao Wenkai Jiang Tian-lin Sun xiao-Di Hu Long-yun Li Chongqing Academy of Chinese Materia Medica 400065 ChongqingChina Chongqing Engineering Research Center for Fine Variety Breeding Techniques of Chinese Materia Medica 400065 ChongqingChina Chongqing Sub-center of National Resource Center for Chinese Materia Medica China Academy of Chinese Medical Science400065 ChongqingChina Novogene Bioinformatics Institute Building 301Zone A10 Jiuxianqiao North 13 RoadChaoyang District100083 BeijingChina

Coptis chinensis Franch, a perennial herb, is mainly distributed in southeastern China. The rhizome of C. chinensis hasbeen used as a traditional medicine for more than 2000 years in China and many other Asian countries. Thepharmacological activities of C. chinensis have been validated by research. Here, we present a de novo high-qualitygenome of C. chinensis with a chromosome-level genome of ~958.20 Mb, a contig N50 of 1.58 Mb, and a scaffold N50of 4.53 Mb. We found that the relatively large genome size of C. chinensis was caused by the amplification of longterminal repeat (LTR) retrotransposons. In addition, a whole-genome duplication event in ancestral Ranunculales wasdiscovered. Comparative genomic analysis revealed that the tyrosine decarboxylase (TYDC) and (S)-norcoclaurinesynthase (NCS) genes were expanded and that the aspartate aminotransferase gene (ASP5) was positively selected inthe berberine metabolic pathway. Expression level and HPLC analyses showed that the berberine content was highestin the roots of C. chinensis in the third and fourth years. The chromosome-level reference genome of C. chinensisprovides important genomic data for molecular-assisted breeding and active ingredient biosynthesis.

关键词： berberine Coptis insight

Transformation and separation of metallic iron in reduced ilmenite during corrosion process

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Journal of Iron and Steel Research International 2020年第12期27卷 1372-1381页

作者： Fu-qiang Zheng xia Liu Yu-feng guo Shuai Wang Feng Chen Ling-zhi Yang Tao Jiang Guan-zhou Qiu School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Hunan Qingzhiyuan Environmental Protection Technology Co. Ltd.Changsha 410083HunanChina

The effects of corrosion temperature, oxygen flow rate and corrosion time on the transformation of metallic iron were systematically studied, and the effects of mineral phases of Fe-bearing products on Ti-Fe separation were investigated. The reaction mechanism of metallic iron in corrosion process was proposed. The results showed that corrosion temperature played a key role in determining the transformation of metallic iron in reduced ilmenite during corrosion process. Under suitable corrosion conditions, Fe-bearing mineral in reduced ilmenite could be converted to amorphous ferric hydroxide, lepidocrocite,hematite and magnetite, respectively, and lepidocrocite was the most easily separated Fe-bearing mineral from corrosion products owing to the significant density difference between lepidocrocite and Ti-rich materials. The Ti-rich material with 77.81 wt.% TiO2 and Fe-bearing product with 52.69 wt.% total Fe were obtained by gravity separation. The Ti recovery ratio and Fe recovery ratio were 91.16% and 86.27%, respectively.

关键词： Reduced ilmenite Corrosion Ti-rich material Fe-bearing mineral Lepidocrocite Metallic iron

Wave Attenuation Performance and the Influencing Factors of A Lower Arc-Plate Breakwater

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China Ocean Engineering 2020年第1期34卷 89-98页

作者： LI Xue-yan WANG Qing YOU Zai-jin guo Wei-jun ZHANG jun-bin ZHAN Chao ZHANG Zhi-chen WANG Li-xue LI Qin Coast Institute Ludong UniversityYantai 264025China Dalian Maritime University Dalian 116026China Institute of Sea-Crossing Engineering Ludong UniversityYantai 264024China College of Environmental Sciences and Engineering Dalian Maritime UniversityDalian 116026China

Comprehensive experimental and numerical studies have been undertaken to investigate wave energy dissipation performance and main influencing factors of a lower arc-plate breakwater. The numerical model, which considers nonlinear interactions between waves and the arc-plate breakwater, has been constructed by using the velocity wave- generating method, the volume of fluid (VOF) method and the finite volume method. The results show that the relative width, relative height and relative submergence of the breakwater are three main influencing factors and have significant influence on wave energy dissipation of the lower arc-plate open breakwater. The transmission coefficient is found to decrease with the increasing relative width, and the minimum transmission coefficient is 0.15 when the relative width is 0.45. The reflection coefficient is found to vary slightly with the relative width, and the maximum reflection coefficient is 0.53 when the relative width is 0.45. The transmission and reflection coefficients are shown to increase with the relative wave height for approximately 85% of the experimental tests when the relative width is 0.19 0.45. The transmission coefficients at relative submergences of 0.04, 0.02 and 0 are clearly shown to be greater than those at relative submergences of 0.02 and 0.04, while the reflection coefficient exhibits the opposite relationship. After the wave interacts with the lower arc-plate breakwater, the wave energy is mainly converted into transmission, reflection and dissipation energies. The wave attenuation performance is clearly weakened for waves with greater heights and longer periods.

关键词： arc-plate breakwater wave attenuation performance influencing factors VOF method