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Recent advances in the culture-independent discovery of natural products using metagenomic approaches

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Chinese Journal of Natural Medicines 2024年第02期 100-111页

作者： shen yiping LIU Nan WANG Zongqiang Laboratory of Microbial Drug Discovery China Pharmaceutical University

Natural products derived from bacterial sources have long been pivotal in the discovery of drug leads. However, the cultivation of only about 1% of bacteria in laboratory settings has left a significant portion of biosynthetic diversity hidden within the genomes of uncultured bacteria. Advances in sequencing technologies now enable the exploration of genetic material from these metagenomes through culture-independent methods. This approach involves extracting genetic sequences from environmental DNA and applying a hybrid methodology that combines functional screening, sequence tag-based homology screening, and bioinformatic-assisted chemical synthesis. Through this process, numerous valuable natural products have been identified and synthesized from previously uncharted metagenomic territories. This paper provides an overview of the recent advancements in the utilization of culture-independent techniques for the discovery of novel biosynthetic gene clusters and bioactive small molecules within metagenomic libraries.

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固溶温度对Fe-30Mn-8Al-0.8C低密度钢组织及力学性能的影响

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钢铁 2024年第2期59卷 129-138页

作者：张琪沈逸平陈光辉薛正良徐光武汉科技大学省部共建耐火材料与冶金国家重点实验室湖北武汉430081 钢铁冶金及资源利用省部共建教育部重点实验室湖北武汉430081 浙江红鹰集团股份有限公司红鹰新型耐火材料研究院浙江湖州313000

为了研究900~1100℃不同固溶温度处理后Fe-30Mn-8Al-0.8C(质量分数,%)低密度钢的组织演变规律和力学性能,采用OM、EBSD和XRD对奥氏体晶粒的长大行为进行了分析,采用Sallars模型拟合了不同固溶温度和时间处理后的奥氏体晶粒尺寸,建立了... 详细信息

为了研究900~1100℃不同固溶温度处理后Fe-30Mn-8Al-0.8C(质量分数,%)低密度钢的组织演变规律和力学性能,采用OM、EBSD和XRD对奥氏体晶粒的长大行为进行了分析,采用Sallars模型拟合了不同固溶温度和时间处理后的奥氏体晶粒尺寸,建立了奥氏体长大模型。采用拉伸试验机和硬度计测试试验钢的力学性能,根据拉伸试验和显微硬度试验结果,分析了试验钢的微观组织与力学性能的关系。结果表明,试验钢在900℃固溶处理90 min后基体组织为奥氏体,但仍存在未溶的κ-碳化物,在其他固溶温度处理后的试样碳化物完全溶解,组织均为奥氏体单相。随着固溶温度的升高,奥氏体晶粒尺寸增大,对奥氏体晶粒长大行为进行拟合分析,给出了固溶温度、保温时间与奥氏体晶粒尺寸关系模型。随着固溶温度升高,伸长率、屈服强度和抗拉强度逐渐降低,由于900℃试样中存在未被完全固溶的κ-碳化物导致试样提前断裂,因此在900℃固溶处理的试样的伸长率略低于950℃试样。试验钢在950℃固溶处理90 min后可获得最佳的强度和塑性配合,强塑积可达44.3 GPa·%。随着固溶温度升高,加工硬化率降低,导致抗拉强度的加工硬化项降低。根据Hall-Petch关系,给出了试验钢屈服强度和晶粒尺寸的关系方程,结合奥氏体晶粒长大模型,可以预测固溶态高锰高铝Fe-30Mn-8Al-0.8C奥氏体低密度钢的力学性能。

关键词：低密度钢固溶处理奥氏体晶粒长大力学性能

Designing a simple multiplex ligation-dependent probe amplification (MLPA) assay for rapid detection of copy number variants in the genome

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Journal of Genetics and Genomics 2009年第4期36卷 257-265页

作者： yiping shen Bai-Lin Wu Children's Hospital Boston Harvard University Boston MA 02115 USA Institutes of Biomedical Science Fudan University Shanghai 200032 China

Copy number variants （CNVs） are pervasive in the human genome and are responsible for many Mendelian diseases and genomic disorders. The detection of CNVs is an essential element of a complete mutation screening strategy. Many techniques have been developed for gene dosage testing. Multiplex ligation-dependent probe amplification （MLPA） is a robust, easy and flexible technique that can detect both deletions and duplications for more than 40 loci in one assay. It has been widely used in research and diagnostic laboratories. We routinely develop our own MLPA assays for quick validation of array comparative genomic hybridization （CGH） findings. Here we discuss the general principles and critical aspects of MLPA assay development and validation using all synthetic MLPA probes. We believe that MLPA will play important roles in the rapid detection of genomic disorders associated with genomic imbalances, the confirmation of pathogenic mutations involving exonic deletions/duplications, CNV genotyping and population frequency analysis of CNVs.

关键词： CGH CNV genomic disorders microdeletion microduplication MLPA

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直升机尾传动轴弹体冲击动力响应与失效破坏

兵器装备工程学报 2024年第5期45卷 119-128页

作者：吴启舟沈意平王送来李坚赵思波蔡志华谭广明湖南科技大学机械设备健康维护湖南省重点实验室湖南湘潭411201 中国航发湖南动力机械研究所湖南株洲412002

直升机在低空作战时,尾传动轴易被地面高射枪弹击中产生弹击损伤。为获得弹体入射角度和速度对尾传动轴动力响应与失效破坏的影响,本文中建立了尾传动轴弹体冲击动力学有限元模型,结合实验验证了有限元模型的准确性,分析了弹体在不同入... 详细信息

直升机在低空作战时,尾传动轴易被地面高射枪弹击中产生弹击损伤。为获得弹体入射角度和速度对尾传动轴动力响应与失效破坏的影响,本文中建立了尾传动轴弹体冲击动力学有限元模型,结合实验验证了有限元模型的准确性,分析了弹体在不同入射角度和速度下尾传动轴的失效破坏规律,计算了弹体不同入射角度下尾传动轴凸面和凹面的临界穿透速度,得到了弹体入射角度、速度与2次冲击力峰值及其时间间隔函数变化关系,提出了一种弹体冲击参数估算方法。分析结果表明,尾传动轴的失效破坏形式呈向后翻转的花瓣型,射出孔损伤比射入孔更大;其凸面和凹面临界穿透速度随弹体入射角度的增大而增大,弹体速度远大于凸凹面临界穿透速度或正冲击时,弹道轨迹无明显偏转;冲击力峰值随弹体入射角度的增大而减小,随弹体速度的增大而增大,而2次冲击力峰值时间间隔随弹体入射角度的增大而增大,随弹体速度的增大而减小;基于2次冲击力峰值时间间隔和弹道轨迹路程能有效计算弹体冲击参数,误差在5%以内。这将为在线监测尾传动轴弹击状态提供参考依据,确保直升机在严酷战场中的安全飞行与任务执行。

关键词：尾传动轴弹体冲击穿透速度失效破坏 2次冲击力峰值时间间隔

孔隙率对风电滑动轴承激光熔覆涂层摩擦磨损性能的影响

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轴承 2024年第9期 79-87页

作者：张益林沈意平张亚宾卫芬鲁学良湖南科技大学机械设备健康维护湖南省重点实验室湖南湘潭411201 湖南科技大学机电工程学院湖南湘潭411201 湖南崇德科技股份有限公司湖南湘潭411101

通过微观组织平均视场法测定了风电齿轮箱行星轮滑动轴承CuSn12Ni2激光熔覆涂层的孔隙率,开展了干摩擦和油润滑条件下不同孔隙率涂层的摩擦磨损试验,运用Archard磨损公式并基于UMESHMOTION子程序在ABAQUS有限元软件中模拟了不同孔隙率... 详细信息

通过微观组织平均视场法测定了风电齿轮箱行星轮滑动轴承CuSn12Ni2激光熔覆涂层的孔隙率,开展了干摩擦和油润滑条件下不同孔隙率涂层的摩擦磨损试验,运用Archard磨损公式并基于UMESHMOTION子程序在ABAQUS有限元软件中模拟了不同孔隙率涂层的摩擦磨损过程。研究结果表明:在干摩擦和油润滑条件下涂层的磨损形式为黏着磨损和磨粒磨损,孔隙率越高涂层磨粒磨损越明显;10,20 N载荷下涂层磨痕位置硬度增幅、磨损深度、磨损宽度、磨损率与孔隙率呈正相关,涂层表面硬度、摩擦系数标准差、摩擦系数平均值与孔隙率呈反相关,孔隙缺陷降低了涂层的摩擦磨损性能;30 N载荷下不同孔隙率涂层摩擦系数标准差、摩擦系数平均值较为接近;载荷越大,孔隙率对涂层摩擦磨损性能的影响越小。

关键词：滑动轴承风电轴承激光熔覆孔隙率摩擦系数有限元分析

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车轴压装界面微动磨损尺寸的非线性检测

无损检测 2024年第8期46卷 54-62页

作者：吴伟沈意平胡斌梁王送来蒋帅湖南科技大学机械设备健康维护湖南省重点实验室湘潭411201 湖南铁道职业技术学院智能制造学院株洲412001

针对铁路车轴压装界面早期微动磨损检测困难的问题,基于Comsol软件固体力学-弹性波多物理场耦合模块,建立含微动磨损的车轴压装界面超声检测分析模型。以透射信号基波及二次谐波的幅值为特征量构建了超声波非线性系数与超声透射系数,讨... 详细信息

针对铁路车轴压装界面早期微动磨损检测困难的问题,基于Comsol软件固体力学-弹性波多物理场耦合模块,建立含微动磨损的车轴压装界面超声检测分析模型。以透射信号基波及二次谐波的幅值为特征量构建了超声波非线性系数与超声透射系数,讨论了压装界面磨损深度、长度以及压装力对超声波非线性系数与超声透射系数的影响,提出车轴压装界面微动磨损尺寸评估模型。结果表明,非线性系数随着压装界面磨损深度、长度的增大而增大,随压装力的增大而减小;超声透射系数随压装界面磨损深度、长度的增大而减小,随压装力的增大而增大。该结论为车轴压装界面微动磨损的尺寸定量评估提供了理论参考。

关键词：车轴压装界面微动磨损尺寸压装力非线性系数超声透射系数

Next-generation sequencing based molecular testing is an equalizer for diagnostic service of rare genetic disorders in China

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Pediatric Investigation 2018年第2期2卷 96-97页

作者： yiping shen Research Institute for Birth Defect Prevention and Control Guangxi Maternal and Child Health Hospital Guangxi China Department of Medical Genetics at Shanghai Children's Medical Center Shanghai Jiao Tong University School of MedicineShanghai China Division of Genetics and Genomics at Boston Children's Hospital Harvard Medical School Boston USA

The traditional approach of clinical genetic practice,known as the phenotype-first approach,usually starts with a thorough review of electronic medical records of the patient and a complete evaluation of patient's clinical presentation,as well as a survey of family *** more than one experienced clinical geneticists will order a variety of additional laboratory or imaging tests to obtain relevant information in order to reach a reasonable clinical ***,molecular testing often helps to confirm the clinical *** practice requires the availability of electronic medical records,well trained clinical geneticists who are able to perform relevant clinical evaluation,order appropriate tests and understand the molecular *** critical components of clinical genetics are mostly lacking in China today,1 as a consequence,most of patients with genetic condition do not receive a proper evaluation by clinical geneticists,only a small percent of patients received a clinical diagnosis and the majority remains undiagnosed for life.

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Effect of kidney-reinforcing,blood-activating and stasis-removing recipes on adhesion molecule expression of bone marrow mesenchymal stem cells from chronic aplastic anemia patients

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Journal of Traditional Chinese Medicine 2012年第4期32卷 596-603页

作者： Baodong Ye Dan Chen Dijiong Wu Xiangping Wu Xiang Zhang Yuhong Zhou yiping shen Keding Shao Qinhong Yu Department of Hematology The First Affiliated HospitalZhejiang University of Traditional Chinese Medicine

OBJECTIVE： To explore the effect of kidney-rein- forcing, blood-activating and stasis-removing recipes on adhesion molecule expression of bone mar- row mesenchymal stem cells （MSCs） from patients with chronic aplastic anemia （CAA）. METHODS： We used three Traditional Chinese Medicine recipes, namely a kidney-reinforcing recipe （KRR）, blood-activating and stasis-removing recipe （BASRR）, and kidney-reinforcing, blood-activating and stasis-removing recipe （KRBASFIR）, and a nor- mal saline control to prepare herbal medicine se- rum in Sprague Dawley rats. Thirty CAA patients were enrolled in the experimental group, including 17 kidney-Yang deficient patients and 13 kidney-Yin deficient patients. Ten healthy individuals were included in the control group. MSCs were isolated from bone marrow samples, and the cell density was observed to measure their proliferation ability by microscopy on days 2, 7, and 14 after isolation. In addition, the expression of adhesion molecules of bone marrow MSCs （CD106, CD49d, CD31 and CD44） were detected by flow cytometry after 48 h of treatment with the four different herbal medi- cine serums. RESULTS： The proliferation of MSCs from kid- ney-Yang deficient and kidney-Yin deficient pa- tients was weaker than that of MSCs from the con- trol group. The expression of all adhesion mole- cules of bone marrow MSCs from CAA patients was obviously lower than that in the control group （P〈 0.01）. The expression of CD49d and CD31 in MSCs from patients with a kidney-Yin deficiency was low- er than in those with a kidney-yang deficiency （P〈 0.05 and P〈O.01, respectively）. For kidney-Yang defi- cient patients, CD31 expression in the KRBASRR group was significantly higher than that in the BASRR group （P〈O.01）, while CD44 in the KRBASRR group was significantly higher than that in both KRR and BASRR groups （P〈O.01）. For kidney-Yin defi- cient patients, CD106 and CD49d expression in the KRBASRR group was obviously higher than that in the KRR group （P〈0.05）, wh

关键词： Anemia Aplastic Bone marrow Mesen-chymal stem cells Cell adhesion molecules Rein-forcing kidney Blood-activating stasis-removing

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将巴西打造成海外深水石油核心产区的思考

国际石油经济 2024年第1期32卷 62-71页

作者：沈一平宋成鹏刘祚冬季天愚李恒萱中国石油勘探开发研究院

当下,全球深水、超深水已经成为国际石油公司跨国油气勘探开发的重要领域。在分析巴西国际油气合作基础、发展现状及趋势的基础上,通过计算全球主要深水油气资产的单桶盈亏平衡油价,认为巴西深水-超深水极具勘探开发成本优势。对比分析... 详细信息

当下,全球深水、超深水已经成为国际石油公司跨国油气勘探开发的重要领域。在分析巴西国际油气合作基础、发展现状及趋势的基础上,通过计算全球主要深水油气资产的单桶盈亏平衡油价,认为巴西深水-超深水极具勘探开发成本优势。对比分析6大国际石油公司和中国石油公司在巴西的布局策略,认为中国石油公司在作业者身份获取及勘探资产部署两方面有所欠缺。提出了新形势下中国石油公司在巴西的投资策略,即通过深化与巴西国家石油公司的战略合作,将巴西项目打造成海外深水石油核心产区。具体措施包括:提前购买多用户地震数据,超前评价,有效支撑未来永久招标模式的投标决策和优质项目获取;通过参股、联合作业到独立作业“三步走”战略,补足深水作业短板;以多种方式获取勘探开发各类资产,快速培植核心产区。

关键词：巴西深水国际石油公司作业者油气资产配置