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Altered intestinal microbiota associated with colorectal cancer

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Frontiers of Medicine 2019年第4期13卷 461-470页

作者： Hong Zhang Ying Chang qingqing zheng Rong Zhang Cheng Hu Weiping Jia Shanghai Diabetes Institute Shanghai Key L aboratory of Diabetes Mellitus Shanghai Clinical Center for Diabetes Shanghai Jiao Tong University Affiliated Sixth People's Hospital Shanghai 200233 China Digestive Endoscopic Center Shanghai Jiao Tong University Affiliated Sixth People's Hospital Shanghai 200233 China

The gut microbiota plays an important role in the development and progression of colorectal cancer (CRC). To learn more about the dysbiosis of carcinogenesis, we assessed alterations in gut microbiota in patients with CRC. A total of 23 subjects were enrolled in this study: 9 had CRC (CRC group) and 14 had normal colons (normal group). The microbiome of the mucosal-luminal interface of each subject was sampled and analyzed using 16S rRNA gene amplicon sequencing. We also used Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) to predict microbial functional profiles. The microbial composition of the mucosal lumen differed between the groups, and the presence of specific bacteria may serve as a potential biomarker for colorectal carcinogenesis. We identified a significant reduction in Eubacterium, which is a butyrate-producing genera of bacteria, and a significant increase in Devosia in the gut microbiota of CRC patients. Different levels of gut microflora in healthy and CRC samples were identified. The observed abundance of bacterial species belonging to Eubacterium and Devosia may serve as a promising biomarker for the early detection of CRC.

关键词： colorectal cancer (CRC) gut microbiota intestinal Eubacterium Devosia

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沸石孔结构对植物油催化裂化性能的影响

化工进展 2022年第2期41卷 750-758页

作者：郑庆庆洪阳冶化工程科技有限公司北京102200

制备出硅铝比相近但介孔体积逐渐增加的超稳Y(USY)沸石,进而制备成微球状催化剂。本文在固定流化床装置上,考察了两种植物油的催化裂化性能。小桐子油的评价结果表明,催化剂中USY沸石的介孔体积越大,汽柴油收率越高;汽油族组成中烯烃收... 详细信息

制备出硅铝比相近但介孔体积逐渐增加的超稳Y(USY)沸石,进而制备成微球状催化剂。本文在固定流化床装置上,考察了两种植物油的催化裂化性能。小桐子油的评价结果表明,催化剂中USY沸石的介孔体积越大,汽柴油收率越高;汽油族组成中烯烃收率越高,芳烃收率越低,汽油辛烷值和抗爆指数也越低;采用铵交换和水热改性制备介孔体积为0.142cm^(3)/g的USY沸石催化剂的裂化产物中,汽柴油总收率为62.21%(质量分数),焦炭收率最低,汽油研究法辛烷值达到90.5;大豆油的催化裂化反应规律与小桐子油的一致,中等介孔催化剂裂化得到的汽油研究法辛烷值达到92.2。研究结果表明,采用催化裂化工艺,利用适当介孔的USY沸石催化剂,可以将植物油高效转化为车用轻质燃料,并且得到高辛烷值的汽油。

关键词：沸石离子交换催化催化剂

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Corneal stromal cells restoration in vitro by exosome derived from ADSCs

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Corneal stromal cells restoration in vitro by exosome derive...

2018年浙江省医学会激光医学分会学术年会暨浙江省医学会激光医学分会第二届学术年会

作者： Ting Shen qingqing zheng Jiang Shen Zhejiang Provincial people’s Hospital

Adipose-derived mesenchymal stem cells(ADSCs) have been reported as an important component of the regenerative *** stromal cells(CSCs),as components of the corneal endothelial microenvironment,can be induced into a functional tissue-engineered corneal *** have demonstrated that ADSCs treatment leads to the phenotypic changes of CSCs in ***,the underlying mechanisms remain ***,we evaluated the effects of ADSCs-derived exosomes on CSCs in vitro using CCK-8 assays,Annexin V-FITC/PI assays,western blot and morphological *** tracking analysis technique(NTA) revealed ADSCsderived exosomes appeared as nanoparticles(40-200 nm),and western blot confirmed its positive expression of CD9,CD81,flotillin-1,and *** ADSCs exosome-treated CSCs showed significant difference in proliferation,apoptosis,especially the expression of extracellular matrix(ECM) related proteins,compared to the control ***-derived exosomes significantly promoted proliferation and inhibited the apoptosis of ***,MMPs were downregulated and collagens were upregulated in exosomes-treated *** of MMPs partially impeded the degradation of ECM,and increase of collagens contributed the ECM synthesis in *** findings indicate that ADSCs play an important role during CSCs’ ECM remodeling,which is closely related to phenotypic changes,partially through the secretion of exosomes.

关键词： Adipose-derived mesenchymal stem cell corneal stromal cells extracellular matrix synthesis exosomes

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生产性服务业对中国城市经济韧性的影响

热带地理 2022年第12期42卷 1953-1963页

作者：杨帆郑晴晴中山大学地理科学与规划学院广州510006

以“后危机时代”中国285个地级及以上城市为例,采用多重中介效应模型探究生产性服务业对经济韧性的影响及其作用机制。结果显示:1)生产性服务业既可通过增加产业结构的非相关多样化直接增强城市经济抵抗力,也可通过增强产业结构的相关... 详细信息

以“后危机时代”中国285个地级及以上城市为例,采用多重中介效应模型探究生产性服务业对经济韧性的影响及其作用机制。结果显示:1)生产性服务业既可通过增加产业结构的非相关多样化直接增强城市经济抵抗力,也可通过增强产业结构的相关多样化诱发技术创新,间接提升城市经济抵抗力和恢复力。2)基于生产性服务业发展水平和城市产业基础的不同,生产性服务业对经济抵抗力和恢复力的影响在东、中、西部城市存在差异。东部城市的直接和间接影响均较为突出。生产性服务业对中部城市的影响主要集中在促进技术创新的中介效应,而西部城市生产性服务业对经济韧性的作用则不显著。3)生产性服务业的细分行业中,信息服务业的直接和间接作用均最为显著,商务服务业对经济韧性的影响相较其他行业弱。

关键词：产业结构生产性服务业经济韧性相关多样化非相关多样化中介效应中国

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A PID Gain Adjustment Scheme Based on Reinforcement Learning Algorithm for a Quadrotor

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A PID Gain Adjustment Scheme Based on Reinforcement Learning...

第三十九届中国控制会议

作者： zheng qingqing Tang Renjie Gou Siyuan Zhang Weizhong School of Aerospace Engineering Beijing Institute of Technology

In this paper, a PID gain adjustment scheme with the basis on Reinforcement Learning Algorithm is proposed, the validity of the scheme is demonstrated with the application to the control of a quadrotor. Specifically, the PPO algorithm of reinforcement learning is utilized in the scheme to adjust a PID controller gains. The procedure and details of the scheme are presented. The experiments prove that the control strategy with this scheme can quickly make the controlled system converge and stabilize. The scheme, compared with a traditional PID controller, has a good performance in terms of control stability, antiinterference stability, and aircraft altitude stability.

关键词： Quadrotor Control PID controller Reinforcement learning PPO algorithm

不同硅铝比NaY沸石混合改性对孔结构和酸性的影响

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石油科学通报 2022年第4期7卷 604-612页

作者：郑庆庆洪阳冶化工程科技有限公司北京102200

研究了不同硅铝比NaY沸石先混合再进行铵离子交换和水热处理对USY沸石孔结构和酸性质的影响。对改性所得的USY沸石进行X射线衍射、低温氮气物理吸附脱附、固体铝核磁、氨气程序升温吸附脱附、扫描电镜、投射电镜等表征分析,结果表明,混... 详细信息

研究了不同硅铝比NaY沸石先混合再进行铵离子交换和水热处理对USY沸石孔结构和酸性质的影响。对改性所得的USY沸石进行X射线衍射、低温氮气物理吸附脱附、固体铝核磁、氨气程序升温吸附脱附、扫描电镜、投射电镜等表征分析,结果表明,混合改性所得USY沸石的相对结晶度为70%,孔分布比较集中,介孔体积为0.200 cm^(3)·g^(-1),最可几分布为10 nm,酸量较高。与高硅铝比NaY沸石单独改性所得USY沸石相比,能明显提高介孔体积和酸量。与低硅铝比NaY沸石单独改性所得USY沸石相比,能提高相对结晶度和酸量。与两种硅铝比NaY沸石分别改性后再进行机械混合所得的混合USY沸石相比,提高了酸量。混合改性USY沸石既含有丰富的介孔,又保留了较高的酸量。以重油为原料的催化裂化评价结果表明,混合改性所得USY沸石制备的催化剂与对比催化剂相比具有较好的重油转化能力,汽柴油总收率达到61.96wt%,焦炭收率为8.23wt%。

关键词：沸石硅铝比改性孔结构酸性催化剂催化

维普期刊数据库

AnAkr encoding a predicted palmitoyl transferase involves in the function of the high-affinity calcium system in Aspergilli

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AnAkr encoding a predicted palmitoyl transferase involves in...

2014年第七届中国模式真菌研讨会

作者：张元炜 qingqing zheng Jinxing Song Lina Gao Ling Lu Jiangsu Key Laboratory for Microbes and Functional Genomics Jiangsu Engineering and Technology Research Center for MicrobiologyCollege of Life SciencesNanjing Normal University

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Research on Equivalent Acceleration Method of Body-in-White Endurance Test

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Research on Equivalent Acceleration Method of Body-in-White ...

2022中国汽车工程学会年会暨展览会

作者： Hou Xianxiao Wang Xicheng Wang Bin zheng qingqing Ji Xiuye DongFeng Motor Corporation Technical Center

In this paper,an acceleration method based on load-equivalent correlation of body-in-white endurance test is *** the BIW durable load target decomposition as the research object,the damage quantity and weight value under various characteristic road conditions are calculated by using the pseudo-damage equivalence theory *** with frequency domain power spectrum density(PSD) analysis,the key characteristic conditions were identified,and an acceleration scheme for BIW endurance test was *** simulation calculation and road test,the effective correlation of durability failure under this scheme is obtained,and the simulation and test cycles are shortened 6 times and 13.8 times respectively,greatly reducing the development cycle of *** method provides an important engineering reference for the development of durability performance of vehicle and parts.

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Corneal Alkali Burn and Medical Managements

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Corneal Alkali Burn and Medical Managements

2014浙江省眼科学术年会

作者： Li Wenwei zheng qingqing Liu Qiping Shen Ting Hong Chaoyang 浙江同德医院眼科

Objective:Corneal chemical burn,especially the corneal alkali burn,is always posing a variety of dilemmas to the *** injuries of the eye produce extensive damage to the ocular surface epithelium,cornea,anterior segment and limbal stem cells resulting in permanent unilateral or bilateral visual *** of the epidemiology,the etiology and the pathology will help us deal with it more *** measures taken are

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