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克氏梭菌硫解酶的鉴定及其功能研究

微生物学报 2019年第1期59卷 79-92页

作者：杨娇任聪徐岩江南大学生物工程学院酿酒科学与酶技术研究中心江苏无锡214122 江南大学教育部工业生物技术重点实验室江苏无锡214122

【目的】硫解酶是梭菌属微生物合成短中链脂肪酸的关键酶。克氏梭菌(Clostridium kluyveri)具有3个高度同源的硫解酶编码基因,对这3个基因的功能鉴定是解析克氏梭菌高己酸合成能力的关键。【方法】通过发酵动力学分析确定克氏梭菌的己... 详细信息

【目的】硫解酶是梭菌属微生物合成短中链脂肪酸的关键酶。克氏梭菌(Clostridium kluyveri)具有3个高度同源的硫解酶编码基因,对这3个基因的功能鉴定是解析克氏梭菌高己酸合成能力的关键。【方法】通过发酵动力学分析确定克氏梭菌的己酸和丁酸生成动力学特征;转录组测序结合反转录-荧光定量RCR分析克氏梭菌3个硫解酶编码基因的表达水平和时序表达特征;在大肠杆菌中异源表达这3个硫解酶,并对其硫解酶动力学参数进行测定。【结果】克氏梭菌生成丁酸、己酸、辛酸,其中己酸为主要代谢产物;转录组数据显示,在乙酸消耗完全之前,thlA1基因维持恒定表达,thlA2基因表达时序上调,thlA3基因表达时序下调,转录组测序表明3个硫解酶编码基因均具有较高水平的转录活性,thlA2和thlA3的最高表达量分别约为thlA1的29%和43%;硫解酶动力学参数测定结果表明,克氏梭菌3个硫解酶对于四碳底物均显示出相似的底物亲和力(K_m),但ThlA1对四碳底物的催化效率(k_(cat)/K_m)略低于ThlA2和ThlA3。【结论】克氏梭菌的3个硫解酶均具有催化活性,在克氏梭菌体内均呈活跃表达,表明克氏梭菌拥有3个具有催化活性的硫解酶,这为后续深入研究克氏梭菌己酸合成机理奠定了基础。

关键词：克氏梭菌己酸硫解酶转录组

Selective depression mechanism of combination of lime and sodium humate on arsenopyrite in flotation separation of Zn-As bulk concentrate

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Transactions of Nonferrous Metals Society of China 2022年第2期32卷 668-681页

作者： Qian WEI Liu-yang DONG cong-ren YANG Xue-duan LIU Fen JIAO Wen-qing QIN School of Mineral Processing and Bioengineering Central South UniversityChangsha 410083China

Lime(CaO)and sodium humate(NaHA)were used as the combined depressant for arsenopyrite pre-treated by CuSO_(4) and butyl ***-flotation tests show that the combined depressant CaO and NaHA achieved the selective depression of ***-circuit lab-scale test results indicate that the synergistic effect of CaO+NaHA achieved a satisfactory flotation separation of sphalerite and arsenopyrite,for which the Zn grade and recovery of Zn concentrate were 51.21%and 92.21%,*** angle measurements,adsorption amount measurements and X-ray photoelectron spectroscopy analysis indicate that the dissolved calcium species(mainly as Ca(2+))were adsorbed on the mineral surfaces,thereby promoting NaHA ***,the surface of the arsenopyrite absorbed more amount of calcium species and NaHA than that of the sphalerite,thereby accounting for the strong hydrophilic surface of *** adsorption of NaHA on arsenopyrite was mainly chemical adsorption through its carboxyl groups and Ca atoms,whereas that on sphalerite surface was relatively weak.

关键词： sphalerite arsenopyrite Zn−As bulk concentrate flotation separation lime sodium humate

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脐血间充质干细胞在软骨组织工程中的应用

中国组织工程研究与临床康复 2011年第36期15卷 6809-6812页

作者：王琮仁张寿中南大学湘雅海口医院(海口市人民医院骨科中心) 海南省海口市570208

背景:关节软骨修复再生能力较差,软骨缺损的修复与功能重建是关节外科的一大难题,也是近年研究热点之一,而软骨组织工程技术的发展为其提供了新的思路和方法。目的:总结和分析脐血间充质干细胞的生物学特性及其在软骨组织工程中的研究... 详细信息

背景:关节软骨修复再生能力较差,软骨缺损的修复与功能重建是关节外科的一大难题,也是近年研究热点之一,而软骨组织工程技术的发展为其提供了新的思路和方法。目的:总结和分析脐血间充质干细胞的生物学特性及其在软骨组织工程中的研究与应用。方法:通过计算机检索中国期刊全文数据库及PubMed数据库2000-01/2010-12的有关文献资料,分别以"脐血间充质干细胞,组织工程,软骨缺损"为中文检索词,"umbilical cord blood mesenchymal stem cells,tissue engineering,cartilage repair"为英文检索词,纳入脐血间充质干细胞和软骨组织工程的相关文献,排除重复性研究,共选取33篇文献做进一步分析。结果与结论:脐血间充质干细胞以其固有的取材方便、免疫原性较弱、分化能力强以及被病毒细菌污染率低等特有的优势,成为软骨组织工程理想的种子细胞,将在未来软骨组织工程的研究及应用中发挥重要的作用。

关键词：脐血间充质干细胞诱导分化支架材料组织工程缺损修复

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基于灰色波形理论的铀资源价格预测方法

价格月刊 2016年第11期 10-16页

作者：王聪仁华中科技大学经济学院湖北武汉430074

根据铀资源U3O8现货价格时间序列数据波动幅度不规则的特征,采用非等间隔的灰色波形预测模型,以Ux C咨询公司2010年1月-2014年12月U3O8现货价格的月度数据为原始数据,对其2015年1月-2016年2月的U3O8现货价格进行灰色波形预测。最后,将... 详细信息

根据铀资源U3O8现货价格时间序列数据波动幅度不规则的特征,采用非等间隔的灰色波形预测模型,以Ux C咨询公司2010年1月-2014年12月U3O8现货价格的月度数据为原始数据,对其2015年1月-2016年2月的U3O8现货价格进行灰色波形预测。最后,将该模型预测结果与在价格预测中应用较广泛的基本GM（1,1）模型和ARIMA模型预测结果进行对比,分析结果表明,相比于其他两种模型,灰色波形预测模型预测值与U3O8现货价格真实值具有更好的拟合度,且精确度更高,可用于实际应用。

关键词：铀资源价格灰色波形理论 GM(1,1)模型 ARIMA模型

中华民族共同体视域下“两弹一星”精神传承与践行的时代指向

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青海民族研究 2023年第4期34卷 74-78页

作者：杨玢任聪青海大学青海西宁810016 山西工程技术学院山西阳泉045000

作为红色基因的生动演绎和中国共产党精神谱系的闪亮标识,“两弹一星”精神是党领导人民在社会主义建设探索进程中对民族精神之一脉相承和时代精神之现实淬炼。在中国特色社会主义时代场景中,“两弹一星”精神的传承与践行对推动铸牢中... 详细信息

作为红色基因的生动演绎和中国共产党精神谱系的闪亮标识,“两弹一星”精神是党领导人民在社会主义建设探索进程中对民族精神之一脉相承和时代精神之现实淬炼。在中国特色社会主义时代场景中,“两弹一星”精神的传承与践行对推动铸牢中华民族共同体意识具有重要意义。基于实践论域整体揆褚,“两弹一星”精神的传承与践行:首先,要立足于中华民族共同体建设的时代需求,基于民族精神的历时承继和时代精神的现实拓展,厘清其精神蕴涵的价值指向;其次,要立足于民族国家价值诉求的现实投射,为增强中华民族共同体意识的主体自觉,明晰其价值意涵的时代指向;最后,要立足于铸牢中华民族共同体意识的时代指向,基于民族地域生活场景中的价值诉求,强化其价值意涵的弘扬传播与自觉展演。

关键词： “两弹一星”精神传承与践行铸牢中华民共同体意识

Enhanced invasion in vitro and the distribution patterns in vivo of CD133＋ glioma stem cells

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Chinese Medical Journal 2011年第17期124卷 2599-2604页

作者： YU Sheng-ping YANG Xue-jun ZHANG Bin MING Hao-lang CHEN cong ren Bing-cheng LIU Zhi-feng LIU Bin Department of Neurosurgery Tianjin Medical University General Hospital Tianjin 300052 China

Background Recent studies have suggested that cancer stem cells cause tumor recurrence based on their resistance to radiotherapy and chemotherapy. Although the highly invasive nature of glioblastoma cells is also implicated in the failure of current therapies, it is not clear whether cancer stem cells are involved in invasiveness. This study aimed to assess invasive ability of glioma stem cells （GSCs） derived from C6 glioma cell line and the distribution patterns of GSCs in Sprague-Dawley （SD） rat brain tumor. Methods Serum-free medium culture and magnetic isolation were used to gain purely CD133＋ GSCs. The invasive ability of CD133＋ and CD133- C6 cells were determined using matrigel invasion assay. Immunohistochemical staining for stem cell markers and luxol fast blue staining for white matter tracts were performed to show the distribution patterns of GSCs in brain tumor of rats and the relationship among GSCs, vessels, and white matter tracts. The results of matrigel invasion assay were estimated using the Student＇s t test and the analysis of Western blotting was performed using the one-way analysis of variance （ANOVA） test. Results CD133＋ GSCs （number： 85.3±4.0） were significantly more invasive in vitro than matched CD133- cells （number： 25.9=~3.1）（t=14.5, P 〈0.005）. GSCs invaded into the brain diffusely and located in perivascular niche of tumor-brain interface or resided within perivascular niche next to white fiber tracts. The polarity of glioma cells containing GSCs was parallel to the white matter tracts. Conclusions Our data suggest that CD133＋ GSCs exhibit more aggressive invasion in vitro and GSCs in vivo probably disseminate along the long axis of blood vessels and transit through the white matter tracts. The therapies targeting GSCs invasion combined with traditional glioblastoma multiforme therapeutic paradigms might be a new approach for avoiding mali qnant glioma recurrence.

关键词： glioma glioma stem cell invasion white matter tracts

Sizable Residual Quasiparticle Density of States Induced by Impurity Scattering Effect in Ba（Fe1-xCox）2As2 Single Crystals

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Chinese Physics Letters 2010年第3期27卷 278-281页

作者：牟刚曾斌程鹏王钊胜方磊沈冰单磊任聪闻海虎 National Laboratory for Superconductivity Institute of Physics and Beijing National Laboratozy for Condensed Matter Physics Chinese Academy of Sciences PO Box 603 Beijing 100190

Low-temperature specific heat Cp is measured on Ba（Fe1-xCox）2As2 single crystals in a wide doping region. A sizeable residual specific heat coefficient γo is observed in the low temperature limit of all samples. The specific heat jump near Tc, i.e. ΔCp/T／T_c, is also determined. It is found that -γo, ΔCp/T／T_c and Tc all share a similar evolution with doping. These can be well understood within the model of S± pairing symmetry when accounting for the cobalt-dopants as unitary scattering centers in the FeAs planes. Our results reveal a non-trivial impact of impurity scattering in FeAs-based.

关键词： Cold Specific heat Temperature Measurement Heat Heating Accounting Broadcasting Doping

滑动构造下“三软”不稳定煤层高突车场揭煤方法探讨

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煤矿安全 2006年第4期37卷 46-48页

作者：程从仁郑煤集团告成煤矿河南登封452477

分析了告成煤矿以往煤与瓦斯突出的原因,摸索了滑动构造下“三软”不稳定煤层高突车场揭煤方法和应采取的措施,保证了揭煤安全。

关键词：滑动构造 “三软”不稳定煤层高突车场揭煤

Review of tungsten resource reserves,tungsten concentrate production and tungsten beneficiation technology in China

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Transactions of Nonferrous Metals Society of China 2022年第7期32卷 2318-2338页

作者： Xu WANG Wen-qing QIN Fen JIAO Liu-yang DONG Jian-gen GUO Jian ZHANG cong-ren YANG School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China Luoyang Yulu Tungsten Mining Co. Ltd.Luoyang 471500China

Tungsten is a strategic metal that is widely used in various fields such as electron communication,aeronautics and astronautics,materials and chemical engineering,due to its special *** has the largest reserves of tungsten resources and the largest output of tungsten concentrate in the world,and plays a decisive role in the world tungsten *** this work,firstly,the reserves and distribution characteristics of tungsten resources in China were summarized,and the production situation of tungsten concentrate in China was *** on the gross domestic product per capita(GDP/capita),five different annual GDP growth rates were used to estimate China’s tungsten concentrate production in the *** estimation results suggested that if China’s economy continues to grow at the current rate,the accumulative production of tungsten concentrate will exceed current reserves by approximately ***,from the aspects of process flow,beneficiation equipment and flotation reagents,the beneficiation technology development of different types of tungsten ore in China was also reviewed,including wolframite,scheelite and tungsten-bearing ***,taking several representative tungsten mines in China as examples,the classic beneficiation technology of different types of tungsten ores was elucidated in ***,the development direction of tungsten beneficiation technology in the future was put forward,which was of great significance to maintain the superiority of tungsten resources in China.

关键词： tungsten reserves production beneficiation flotation gravity separation