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米曲霉异源表达合成虫草素

生物技术通报 2024年第6期40卷 290-298页

作者：闫欢欢尚怡彤王丽红田学琴廖海艳曾斌胡志宏江西科技师范大学生命科学学院南昌330013 江西科技师范大学江西省生物加工过程重点实验室南昌330013 南昌市微生物资源与代谢重点实验室南昌330013 深圳技术大学药学院深圳518118

【目的】通过米曲霉中异源表达虫草素合成关键基因,构建米曲霉工程菌株合成虫草素。【方法】以米曲霉尿苷/尿嘧啶和组氨酸双营养缺陷型菌株AoΔpyrGΔHisB为背景菌株,利用农杆菌介导的转化方法对虫草素合成关键基因CmCns1-CmCns3进行过... 详细信息

【目的】通过米曲霉中异源表达虫草素合成关键基因,构建米曲霉工程菌株合成虫草素。【方法】以米曲霉尿苷/尿嘧啶和组氨酸双营养缺陷型菌株AoΔpyrGΔHisB为背景菌株,利用农杆菌介导的转化方法对虫草素合成关键基因CmCns1-CmCns3进行过表达;通过荧光显微镜观察CmCns1和CmCns2在米曲霉中的亚细胞定位;利用高效液相色谱法(HPLC)测定转基因米曲霉虫草素含量,同时对米曲霉发酵液添加合成虫草素的前体甘氨酸和腺嘌呤,探究其在米曲霉中对合成虫草素的影响。【结果】蛹虫草CmCns1和CmCns2在米曲霉中定位于脂滴;并且米曲霉中单独过表达CmCns1、共表达CmCns1和CmCns2以及共表达CmCns1-CmCns3均能合成虫草素,发酵48 h虫草素胞外产量最高达到37.74 μg/mL;向米曲霉发酵液添加甘氨酸和腺嘌呤,不能有效提升虫草素的含量。【结论】成功在米曲霉异源表达合成虫草素。

关键词：虫草素米曲霉异源表达亚细胞定位腺嘌呤甘氨酸

Degeneracy and discreteness in cosmological model fitting

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Research in Astronomy and Astrophysics 2016年第3期16卷 121-128页

作者： huan-Yu Teng Yuan huang tong-Jie Zhang Department of Astronomy Beijing Normal UniversityBeijing 100875China Departments of Physics and Astronomy University of CaliforniaBerkeleyCA 94720USA Lawrence Berkeley National Laboratory 1 Cyclotron RoadBerkeleyCA 94720USA

We explore the problems of degeneracy and discreteness in the standard cosmological model（ΛCDM）. We use the Observational Hubble Data（OHD） and the type Ia supernovae（SNe Ia） data to study this issue. In order to describe the discreteness in fitting of data, we define a factor G to test the influence from each single data point and analyze the goodness of G. Our results indicate that a higher absolute value of G shows a better capability of distinguishing models, which means the parameters are restricted into smaller confidence intervals with a larger figure of merit evaluation. Consequently, we claim that the factor G is an effective way of model differentiation when using different models to fit the observational data.

关键词： cosmological parameters -- cosmology: observations -- methods: statistical

A Chaos Sparrow Search Algorithm with Logarithmic Spiral and Adaptive Step for Engineering Problems

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Computer Modeling in Engineering & Sciences 2022年第1期130卷 331-364页

作者： Andi Tang huan Zhou tong Han Lei Xie Aeronautics Engineering College Air Force Engineering UniversityXi’an710038China

The sparrow search algorithm(SSA)is a newly proposed meta-heuristic optimization algorithm based on the sparrowforaging *** to other meta-heuristic algorithms,SSA has problems such as slowconvergence speed and difficulty in jumping out of the local *** order to overcome these shortcomings,a chaotic sparrow search algorithm based on logarithmic spiral strategy and adaptive step strategy(CLSSA)is proposed in this ***,in order to balance the exploration and exploitation ability of the algorithm,chaotic mapping is introduced to adjust the main parameters of ***,in order to improve the diversity of the population and enhance the search of the surrounding space,the logarithmic spiral strategy is introduced to improve the sparrow search ***,the adaptive step strategy is introduced to better control the process of algorithm exploitation and *** best chaotic map is determined by different test functions,and the CLSSA with the best chaotic map is applied to solve 23 benchmark functions and 3 classical engineering *** simulation results show that the iterative map is the best chaotic map,and CLSSA is efficient and useful for engineering problems,which is better than all comparison algorithms.

关键词： Sparrow search algorithm global optimization adaptive step benchmark function chaos map

Influence of Deformation on the Microstructure and Low-temperature Refining Behavior of Al-3.5P Master Alloy

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Journal of Materials Science & Technology 2015年第4期31卷 391-396页

作者： huan Qiao Xiangzhen Zhu tong Gao Yuying Wu Xiangfa Liu Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong University

In this paper,the influence of deformation on the microstructure and low-temperature refining behavior of Al-3.5P master alloy was *** results show that the average size of AIP particles can be reduced obviously from 15.3 μm to about 2.1 μm by ***,it exhibits entirely opposite influence on refining performance when A1-3.5P master alloy was deformed at room temperature and high temperature,*** when Al-3.5P master alloy was subjected to thermal deformation,can an improvement of low-temperature refining performance be *** this condition,primary Si in A390 alloy can be refined from 137 to 21 μm,making it a potential candidate for die casting production.A mechanism associated with the transformation of particle-matrix interface during deformation has been proposed and further experiment has been designed to validate it.

关键词： Al-Si alloy A-P master alloy Deformation Grain ref

蓝布正总酚酸的大孔树脂纯化工艺与质量标准研究

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中国新药杂志 2024年第9期33卷 924-933页

作者：孔熙贤田广环吴桐潘福竺欧阳意吴宏伟中国中医科学院中药研究所北京100700 遵义医科大学药学院遵义563000 遵义医科大学基础药理教育部重点实验室暨特色民族药教育部国际合作联合实验室遵义563000

目的:优化大孔吸附树脂富集蓝布正总酚酸的纯化工艺,建立蓝布正总酚酸部位指纹图谱,并测定二聚鞣花鞣质A、没食子酸乙酯、鞣花酸及总酚酸含量。方法:采用单因素实验,以总酚酸的吸附率、解吸附率以及总酚酸含量、转移率为指标,筛选最佳... 详细信息

目的:优化大孔吸附树脂富集蓝布正总酚酸的纯化工艺,建立蓝布正总酚酸部位指纹图谱,并测定二聚鞣花鞣质A、没食子酸乙酯、鞣花酸及总酚酸含量。方法:采用单因素实验,以总酚酸的吸附率、解吸附率以及总酚酸含量、转移率为指标,筛选最佳大孔树脂型号、吸附条件、除杂条件和解吸附条件;采用HPLC和紫外可见分光光度法,建立总酚酸部位指纹图谱及二聚鞣花鞣质A、没食子酸乙酯、鞣花酸和总酚酸含量测定的质量控制方法。结果:选择HPD-400型大孔树脂,最佳工艺条件为提取物上样质量浓度为8 mg·mL^(-1),吸附流速为2 BV·h^(-1),径高比为1∶8,上样量为3 BV,10%乙醇4 BV洗脱除杂,除杂流速为3 BV·h^(-1),50%乙醇5 BV洗脱,洗脱流速4 BV·h^(-1),3批次验证实验得到的总酚酸平均含量67.75%(RSD为3.02%),平均转移率为74.53%(RSD为1.20%);12批样品指纹图谱中共有个18共有峰,指认了其中6个峰,分别为二聚鞣花鞣质B、二聚鞣花鞣质G、二聚鞣花鞣质A、特里马素Ⅱ、没食子酸乙酯、鞣花酸,相似度均≥0.9,二聚鞣花鞣质A、没食子酸乙酯、鞣花酸、总酚酸含量测定方法学考察符合要求,3种成分在各自范围内线性关系良好(R2≥0.997),平均加样回收率为93.00%~103.53%,RSD为1.92%~3.87%,其12批次样品的含量范围分别为5.35%~15.25%,0.12%~0.62%,1.84%~6.27%,以没食子酸计,总酚酸线性范围良好(R2=0.995),平均加样回收率为95.30%,RSD为1.40%,其12批次样品总酚酸含量范围为53.65%~73.16%。结论:纯化工艺稳定可靠,可用于蓝布正总酚酸部位的富集。指纹图谱与含量测定方法稳定可靠,可用于蓝布正总酚酸部位的质量控制。

关键词：蓝布正总酚酸大孔树脂纯化工艺 HPLC指纹图谱质量控制二聚鞣花鞣质A

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青贮玉米淀粉含量与纤维性状的GWAS分析

玉米科学 2024年第8期32卷 23-30页

作者：倪雪梅胡玉兰李旭刘欢张耕耘魏桐深圳华大生命科学研究院广东深圳518083 深圳市华大农业应用研究院广东深圳518120 广东省农作物核心资源开发应用企业重点实验室广东深圳518083 农业农村部农业基因组学重点实验室广东深圳518083

以青贮玉米自交系GF353与大胚微胚乳玉米自交系20145杂交后自交构建F2群体,通过基因组测序获得300份F2各单株高密度基因型数据,结合淀粉、ADF和NDF含量表型数据进行GWAS分析。结果表明,所用材料中与淀粉相关位点在Chr2、Chr3、Chr7和Chr... 详细信息

以青贮玉米自交系GF353与大胚微胚乳玉米自交系20145杂交后自交构建F2群体,通过基因组测序获得300份F2各单株高密度基因型数据,结合淀粉、ADF和NDF含量表型数据进行GWAS分析。结果表明,所用材料中与淀粉相关位点在Chr2、Chr3、Chr7和Chr8上被检测到,ADF相关位点在Chr4染色体上,NDF相关位点在Chr2染色体上,可为加速培育超级青贮玉米新品种提供基础材料和相关分子标记。

关键词：青贮玉米淀粉含量酸性洗涤纤维中性洗涤纤维 GWAS分析

典型自然源气溶胶沉降引起的海洋初级生产响应

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海洋与湖沼 2024年第2期55卷 363-374页

作者：刘畅毛志华陈焕焕王云涛上海交通大学海洋学院上海200030 自然资源部第二海洋研究所浙江杭州310012

大气沉降是陆源物质向海洋输入营养盐的重要方式,沙尘、野火和火山喷发均能够产生气溶胶,这些典型的自然源气溶胶在风场的作用下,能够进行远距离的输运,期间由于沉降作用进入海洋,为上层海洋提供限制性营养盐促进海洋浮游植物生长,提升... 详细信息

大气沉降是陆源物质向海洋输入营养盐的重要方式,沙尘、野火和火山喷发均能够产生气溶胶,这些典型的自然源气溶胶在风场的作用下,能够进行远距离的输运,期间由于沉降作用进入海洋,为上层海洋提供限制性营养盐促进海洋浮游植物生长,提升海洋的初级生产力,促进碳循环过程。以海表叶绿素浓度作为海洋初级生产力的重要指标,通过海表叶绿素浓度的响应,探究沙尘、野火和火山这三种典型自然源气溶胶的传输路径及其沉降对海洋初级生产的影响。结果显示,海洋初级生产对气溶胶沉降的响应不仅与气溶胶排放类型有关,也与温度、动力过程、光合有效辐射等海域初级生产影响因素有关,体现了海洋初级生产对自然源气溶胶的敏感性,自然源气溶胶沉降所驱动的海洋初级生产在全球碳循环中具有重要的潜在影响。

关键词：自然源气溶胶传输与沉降营养盐海表叶绿素浓度海洋初级生产力

Biomimetic natural biomaterials for tissue engineering and regenerative medicine:new biosynthesis methods,recent advances,and emerging applications

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Military Medical Research 2024年第1期11卷 50-79页

作者： Shuai Liu Jiang-Ming Yu Yan-Chang Gan Xiao-Zhong Qiu Zhe-Chen Gao huan Wang Shi-Xuan Chen Yuan Xiong Guo-Hui Liu Si-En Lin Alec McCarthy Johnson V.John Dai-Xu Wei Hong-Hao Hou Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering the Fifth Affiliated HospitalSchool of Basic Medical ScienceSouthern Medical UniversityGuangzhou 510900China Department of Orthopedics Tongren HospitalShanghai Jiao Tong UniversityShanghai 200336China The Eighth Affiliated Hospital Sun Yat-Sen UniversityShenzhen 518033GuangdongChina Engineering Research Center of Clinical Functional Materials and Diagnosis&Treatment Devices of Zhejiang Province Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhou 325011ZhejiangChina Department of Orthopedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Orthopaedics and Traumatology Faculty of Medicinethe Chinese University of Hong KongHong Kong SAR 999077China Department of Functional Materials Terasaki Institute for Biomedical InnovationLos AngelesCA 90064USA Mary&Dick Holland Regenerative Medicine Program College of MedicineUniversity of Nebraska Medical CenterOmahaNE 68130USA Zigong Affiliated Hospital of Southwest Medical University Zigong Psychiatric Research CenterZigong Institute of Brain ScienceZigong 643002SichuanChina Key Laboratory of Resource Biology and Biotechnology in Western China Ministry of EducationSchool of MedicineDepartment of Life Sciences and MedicineNorthwest UniversityXi’an 710127China

Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative *** contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix(ECM).Additionally,such materials have mechanical adaptability,micro-structure interconnectivity,and inherent bioactivity,making them ideal for the design of living implants for specific applications in TE and regenerative *** paper provides an overview for recent progress of biomimetic natural biomaterials(BNBMs),including advances in their preparation,functionality,potential applications and future *** highlight recent advances in the fabrication of BNBMs and outline general strategies for functionalizing and tailoring the BNBMs with various biological and physicochemical characteristics of native ***,we offer an overview of recent key advances in the functionalization and applications of versatile BNBMs for TE ***,we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field.

关键词： Biomimic Scaffold Biosynthesis Natural biomaterial Tissue engineering

基于网络药理学与分子对接技术探讨小檗皮治疗2型糖尿病的作用机制

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现代药物与临床 2024年第10期39卷 2493-2501页

作者：杜欢徐鑫梅徐僮李琪易欢范刚成都市第三人民医院西南交通大学附属医院成都中医药大学民族医药学院

目的探讨小檗Berberis kansuensis Schneid.皮治疗2型糖尿病的药效物质与作用机制。方法基于藏药小檗皮入血成分，利用SwissADME、TCMSP和Swiss Target Prediction数据库分别开展活性成分初筛、潜在作用靶点预测，其次利用GeneCards、... 详细信息

目的探讨小檗Berberis kansuensis Schneid.皮治疗2型糖尿病的药效物质与作用机制。方法基于藏药小檗皮入血成分，利用SwissADME、TCMSP和Swiss Target Prediction数据库分别开展活性成分初筛、潜在作用靶点预测，其次利用GeneCards、DisGeNET和DrugBank数据库获取2型糖尿病相关靶点，STRING数据库构建靶点蛋白相互作用（PPI）网络筛选核心靶点，根据筛选结果应用R语言开展基因本体（GO）生物功能和京都基因与基因组百科全书（KEGG）通路分析，最终利用Cytoscape 3.10.1软件构建“药材–入血成分–靶点–通路–疾病”互作网络筛选核心成分与关键靶点，以及开展分子对接验证“核心成分–关键靶点”的生物活性。结果活性初筛得到28个候选活性成分，经Swiss Target Prediction预测后，得到571个成分作用靶点；网络药理学分析结果发现，小檗皮与2型糖尿病有306个交集靶点，小檗皮可能通过8-氧化小檗碱、蟾毒色胺、蟾毒色胺内盐、小檗碱、药根碱等成分，分别作用于磷脂酰肌醇3-激酶催化亚型（PIK3CA）、丝氨酸/苏氨酸蛋白激酶（MAPK1）、B细胞κ轻肽基因增强子抑制因子（IKBKB）、蛋白激酶B1(Akt1)和表皮生长因子受体（EGFR）等关键靶点，调节磷脂酰肌醇3激酶（PI3K）/Akt、MAPK、肿瘤坏死因子（TNF）和核因子-κB(NF-κB)等信号通路，协同发挥抗糖尿病作用。结论通过整合入血成分鉴定、网络药理学与分子对接结果，预测了小檗皮治疗2型糖尿病的潜在药效成分和作用靶点，为揭示小檗皮的药效物质基础及其作用机制研究提供参考，也为小檗皮治疗2型糖尿病的深入研究提供靶向。

关键词：小檗皮 2型糖尿病入血成分网络药理学分子对接 8-氧化小檗碱蟾毒色胺蟾毒色胺内盐小檗碱药根碱

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