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Exo-celiac liver in Glyptosternum maculatum

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Progress in Natural Science:Materials International 2007年第9期17卷 1109-1113页

作者： Li Hongjing,Xie Congxin,Li dapeng,Chai Yi,liu Hongyan,Fan Qixue and Zhu Bangke(College of Fisheries,Huazhong Agricultural University,Wuhan 430070,China) College of Fisheries Huazhong Agricultural University Wuhan 430070 China

A unique structure in the fish of Glyptosternum maculatum(Regan)(Siluriformes:Sisoridae)is *** was identified as a part of the liver named "exo-celiac liver".This new organ is located between skin and muscle and connected with the celiac liver by a funiform tissue,"joint belt".It has similar histological features and isozyme electrophoretogramic bands of lactate dehydrogenase,esterase,malate dehydrogenase and alcohol dehydrogenase as in the celiac *** unique organ has biological research value and could serve as an important tool for studying organogenesis and evolution.

关键词： Glyptosternum maculatum(Regan) exo-celiac liver morphology histology enzymology

Effect of kerosene injection states on mixing and combustion characteristics in a cavity-based supersonic combustor

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Chinese Journal of Aeronautics 2024年第4期37卷 308-320页

作者： Xu liu Peibo LI Fei LI Hongbo WANG Mingbo SUN Chao WANG Yixin YANG dapeng XIONG Yanan WANG Science and Technology on Scramjet Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

It has been found that the static pressure distribution along the axial direction of liquid kerosene is lower than that of the gaseous kerosene under the same flow condition and overall equivalent ratio from previous *** further investigate this phenomenon,a compressible two-phase parallel simulation method is utilized to analyze the mixing and combustion characteristics of gaseous and liquid kerosene jets in a cavity-based supersonic *** numerical results are consistent with the experiments and demonstrate that gaseous injection leads to a cavity shear layer that dives deeper into the cavity,forming two recirculation zones in the front and rear of the *** contrast,the cavity shear layer is closer to the mainstream during liquid injection,and only a large recirculation zone is formed in the rear of the *** a result of the cavity shear layer and the recirculating flow,the fuel vapor of gaseous injection accumulates in the front of the cavity,while for the liquid injection,the fuel vapor disperses in the cavity,cavity shear layer,and the region above,and the rear of the cavity has a higher fuel vapor concentration than the *** unique fuel distribution causes the combustion area to be concentrated in the cavity during the gaseous injection but dispersed inside and downstream of the cavity during the liquid *** a result,forming a thermal throat under the same conditions is more challenging during liquid injection,and the generated static pressure distribution is lower than that during the gaseous injection.

关键词： Gaseous injection Liquid injection Mixing process Combustion Supersonic flow

Effect of riboflavin deficiency on intestinal morphology,jejunum mucosa proteomics,and cecal microbiota of Pekin ducks

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Animal Nutrition 2023年第1期12卷 215-226页

作者： Yaxi Xu Bo Zhang Rui Zhao Kexin Gao Suyun Liang Yongbao Wu Yongsheng Hao dapeng liu Zhanbao Guo Jian Hu Zhengkui Zhou Ming Xie Jing Tang State Key Laboratory of Animal Nutrition Key Laboratory of Animal(Poultry)Genetics Breeding and ReproductionMinistry of Agriculture and Rural AffairsInstitute of Animal ScienceChinese Academy of Agricultural SciencesBeijing100193China

This study was to determine the effects of riboflavin deficiency(RD)on intestinal development,jejunum mucosa proteome,cecal short-chain fatty acids(SCFA)profiling,and cecal microbial diversity and community of starter Pekin *** white Pekin ducks(1 d old,n=240)were allocated into 2 groups,with 12 replicates and 10 birds per replicate in each *** 21 d,all ducks had ad libitum access to either an RD or a riboflavin adequate(control,CON)diet,formulated by supplementing a basal diet with 0 or 10 mg riboflavin per kg of diet,*** to the CON group,growth retardation,high mortality,and poor riboflavin status were observed in the RD ***,RD reduced the villus height and the ratio of villus height to crypt depth of jejunum and ileum(P<0.05),indicating morphological alterations of the small *** addition,dietary RD enhanced relative cecum weight and decreased cecal SCFA concentrations(P<0.05),including propionate,isobutyrate,butyrate,and *** jejunum mucosa proteomics showed that 208 proteins were upregulated and 229 proteins were downregulated in the RD group compared to those in the CON *** these,RD mainly suppressed intestinal absorption and energy generation processes such as glycolysis and gluconeogenesis,fatty acid beta oxidation,tricarboxylic acid cycle,and oxidative phosphorylation,leading to impaired ATP *** addition,RD decreased the community richness and diversity of the bacterial community in the cecum of ***,RD reduced the abundance of butyrate-producing bacteria in the cecum(P<0.05),such as Eubacterium coprostanoligenes,Prevotella and *** RD resulted in growth depression and intestinal hypofunction of Pekin ducks,which could be associated with impaired intestinal absorption and energy generation processes in intestinal mucosa,as well as gut microbiota *** findings contribute to our understanding of the mechanisms of intestinal hypofuncti

关键词： Riboflavin Deficiency Intestinal morphology Proteomics Cecal microbiota Short-chain fatty acids

基于SPOC的混合式教学模式在环境基础化学课程教学中的实践

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创新创业理论研究与实践 2024年第7期7卷 108-110页

作者：高明王俊霞沈舒苏刘大朋陈明周晓吉钱飞跃苏州科技大学环境科学与工程学院江苏苏州215009

小规模限制性在线课程(SPOC)的混合教学模式课堂利用率高,正日益引起教育工作者的重视。该文以环境基础化学(一)课程为例,对基于SPOC的混合式教学模式进行详细阐述,针对学习需求及课程特点进行混合教学模式设计,阐明基于SPOC的线上线下... 详细信息

小规模限制性在线课程(SPOC)的混合教学模式课堂利用率高,正日益引起教育工作者的重视。该文以环境基础化学(一)课程为例,对基于SPOC的混合式教学模式进行详细阐述,针对学习需求及课程特点进行混合教学模式设计,阐明基于SPOC的线上线下混合式教学模式在教学实践中的应用,也对线上、线下教学各自的优点和不足进行深入的探讨。

关键词： SPOC 混合教学环境基础化学课程实践环境类专业课程评价

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地下管廊深基坑回填土层沉降特征研究

交通科学与工程 2024年第3期40卷 82-90页

作者：李奉庭罗涛孙占勇武科肖文斌常昊许文彬刘大鹏山东大学土建与水利学院山东济南250061 中国电建市政建设集团有限公司天津300384

为研究城市地下综合管廊回填后路面的沉降规律,依托雄安新区某管廊工程,运用现场回填土层沉降变形物联网智能监测与数值模拟计算方法,建立了综合管廊基坑回填施工过程的力学计算模型,对不同工况下的路面沉降与管廊结构的应力、应变情况... 详细信息

为研究城市地下综合管廊回填后路面的沉降规律,依托雄安新区某管廊工程,运用现场回填土层沉降变形物联网智能监测与数值模拟计算方法,建立了综合管廊基坑回填施工过程的力学计算模型,对不同工况下的路面沉降与管廊结构的应力、应变情况进行分析。研究结果表明:1)回填土体的累积沉降量及各土层间的沉降差随着回填土层厚度的增大而增大。2)在阶梯法回填施工中,施工回填段数越多,路面沉降量及不均匀沉降程度越小,管廊结构变形越大。3)施工后的路面沉降量随着压实度的增大而显著减小。相关模拟方法与研究成果可为类似综合管廊回填工程的方案设计提供参考依据。

关键词：地下管廊回填土沉降变形现场监测数值模拟

Balloon Angioplasty for Symptomatic Intracranial Artery Stenosis (BASIS): protocol of a prospective, multicentre, randomised, controlled trial

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Stroke & Vascular Neurology 2024年第1期9卷 66-74页

作者： Xuan Sun Ming Yang dapeng Sun Guangge Peng Yiming Deng Xingquan Zhao Liping liu Ning Ma Feng Gao dapeng Mo Wengui Yu Yongjun Wang Yilong Wang Zhongrong Miao Department of Interventional Neuroradiology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Neurology Beijing Luhe HospitalCapital Medical UniversityBeijingChina Department of Neurology Comprehensive Stroke&Cerebrovascular CenterUniversity of California IrvineIrvineCaliforniaUSA Chinese Institute for Brain Research BeijingChina National Center for Neurological Diseases BeijingChina Advanced Innovation Center for Human Brain Protection Capital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina Beijing Laboratory of Oral Health Capital Medical UniversityBeijingChina

Background The superiority of balloon angioplasty plus aggressive medical management(AMM)to AMM alone for symptomatic intracranial artery stenosis(sICAS)on efficacy and safety profiles still lacks evidence from randomised controlled trials(RCTs).Aim To demonstrate the design of an RCT on balloon angioplasty plus AMM for *** Balloon Angioplasty for Symptomatic Intracranial Artery Stenosis(BASIS)trial is a multicentre,prospective,randomised,open-label,blinded end-point trial to investigate whether balloon angioplasty plus AMM could improve clinical outcome compared with AMM alone in patients with *** eligible in BASIS were 35–80 years old,with a recent transient ischaemic attack within the past 90 days or ischaemic stroke between 14 days and 90 days prior to enrolment due to severe atherosclerotic stenosis(70%–99%)of a major intracranial *** eligible patients were randomly assigned to receive balloon angioplasty plus AMM or AMM alone at a 1:1 *** groups will receive identical AMM,including standard dual antiplatelet therapy for 90 days followed by long-term single antiplatelet therapy,intensive risk factor management and life-style *** participants will be followed up for *** outcomes Stroke or death in the next 30 days after enrolment or after balloon angioplasty procedure of the qualifying lesion during follow-up,or any ischaemic stroke or revascularisation from the qualifying artery after 30 days but before 12 months of enrolment,is the primary *** BASIS trail is the first RCT to compare the efficacy and safety of balloon angioplasty plus AMM to AMM alone in sICAS patients,which may provide an alternative perspective for treating *** registration number NCT03703635;https://***.

关键词： balloon prospective centre

Examples of unusual ionospheric observations by the CSES prior to earthquakes

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Earth and Planetary Physics 2018年第6期2卷 515-526页

作者： Rui Yan XuHui Shen JianPing Huang Qiao Wang Wei Chu dapeng liu YanYan Yang HengXin Lu Song Xu The Institute of Crustal Dynamics China Earthquake Administration

The CSES(China seismic electromagnetic satellite) was launched on February 2, 2018 in a circular polar orbit at an altitude of～507 km. One of the main objectives of CSES is to search for and characterize ionospheric perturbations that can be associated with seismic activities, to better understand the generation mechanism of such perturbations. Its scientific payload can measure a broad frequency range of electromagnetic waves and some important plasma parameters. This paper is a first-hand study of unusual observations recorded by the CSES over seismic regions prior to four earthquakes with M >7.0 since the satellite's launch. CSES detectors measured irregularities near the epicenter of these four earthquakes. It is already clear that data from instruments onboard the CSES will be of significant help in studies of characteristics of ionospheric perturbations related to earthquakes and their generation mechanisms.

关键词： CSES ionospheric perturbations earthquake

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加氢脱氮催化研究的新进展

化学进展 2006年第4期18卷 417-428页

作者：刘大鹏李永丹天津大学化工学院催化科学与工程系天津300072

化石燃料的加氢脱氮有利于改善油品质量及其稳定性,同时避免燃烧时NOx的排放。本文介绍了不同化石燃料中有机氮化物的含量及类型,对不同加氢脱氮催化剂及其催化活性位的本质进行了探讨,同时论述了C—N键断裂机理及燃料中主要有机氮化物... 详细信息

化石燃料的加氢脱氮有利于改善油品质量及其稳定性,同时避免燃烧时NOx的排放。本文介绍了不同化石燃料中有机氮化物的含量及类型,对不同加氢脱氮催化剂及其催化活性位的本质进行了探讨,同时论述了C—N键断裂机理及燃料中主要有机氮化物的HDN反应网络。着重概述了传统金属硫化物催化剂的改性方法,新型的金属碳化物、金属氮化物和金属磷化物催化剂的研究现状。

关键词：加氢脱氮有机氮化物金属硫化物金属碳化物金属氮化物金属磷化物活性位本质 C—N断裂反应网络

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玉米收储制度改革的得失与启示

农业经济问题 2023年第6期 86-96页

作者：刘颖刘大鹏北方工业大学经济管理学院北京100144 华中农业大学经济管理学院武汉430070

粮食收储制度的完善是全方位夯实粮食安全根基的应有之义。通过梳理粮食收储制度改革的演变历程发现,供需关系变化始终贯穿粮食收储制度演变,依靠市场力量和市场手段是粮食收储制度改革的主要方向与思路。以2016年开始的玉米收储制度改... 详细信息

粮食收储制度的完善是全方位夯实粮食安全根基的应有之义。通过梳理粮食收储制度改革的演变历程发现,供需关系变化始终贯穿粮食收储制度演变,依靠市场力量和市场手段是粮食收储制度改革的主要方向与思路。以2016年开始的玉米收储制度改革为例,下一步玉米收储制度应在“价补分离”的框架下,一是调整政策导向,促进玉米生产恢复发展;二是坚持市场化改革取向与保护农民利益并重,完善玉米生产支持政策体系;三是合理设定储备规模,确保政府宏观调控能力;四是建立玉米深加工补贴动态调整机制,以期巩固或扩大改革成效、实现新形势下的玉米稳产保供。

关键词：玉米收储制度改革产业链价补分离调控能力