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A Novel Material for Selective Separation of Mono-galactosyldiacylglycerols from Microalgae

Journal of Ocean University of China 2021年第1期20卷 221-227页

作者： JIANG Junpeng YANG Miao CAO Xupeng WAN Huihui LIU Shuqin zhong shijun YAN Jingyu XUE Song Biotechnology Department Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Division of Solar Energy Dalian National Laboratory of Clean EnergyDalian 116023China University of Chinese Academy of Sciences Beijing 100049China Faculty of Chemical Environmental and Biological Science and TechnologyAnalytical CenterDalian University of TechnologyDalian 116024China School of Bioengineering Dalian University of TechnologyDalian 116024China Key Lab of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Monogalactosyldiacylglycerols(MGDGs)have potential applications in food products,cosmetics and pharmaceuticals.MGDGs from microalgae with high amounts of polyunsaturated fatty acids(PUFAs)have potential functions,which arise the interest of the researchers.MGDGs were prepared by silica gel column chromatography with the appropriate mobile phase,while due to the similarity to molecular structure of MGDGs,digalactosyldiacylglycerols(DGDGs)were the most difficult impurities to separate during the extraction process of MGDGs from Nannochloropsis oceanica IMET1 and Arthrospira platensis.In order to obtain MGDGs from microalgae using low toxic solvent system,a novel material Click thiol-ene cysteine(Click TE-Cys)was employed to achieve its selective separation by differentiation of the hydrophilic interaction.The mixture of MGDGs and DGDGs standards were separated from each other by Click TE-Cys solid phase extraction(SPE),which was further confirmed by the result of LC-MS.The molecular interaction of MGDGs and DGDGs with Click TE-Cys demonstrated that DGDGs had more hydrogen bonds with Click TE-Cys material,which might cause a higher hydrophilic interaction.In this study,the Click TE-Cys material exhibited higher hydrophilicity with DGDGs and effectively separated MGDGs from 4 species microalgae by‘flow-through'mode using ethanol as mobile phase.

关键词： microalgae MGDGs DGDGs selective separation polarity

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Lithospheric structure beneath Ordos Block and surrounding areas from joint inversion of receiver function and surface wave dispersion

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Science China Earth Sciences 2022年第7期65卷 1399-1413页

作者： Jianping WU Yaning LIU shijun zhong Weilai WANG Yan CAI Wei WANG Jing LIU Institute of Geophysics China Earthquake AdministrationBeijing 100081China Beijing Earthquake Agency Beijing 100080China

Ordos Block has undergone rapid uplift,and a series of rift basins have been formed around the block since the Cenozoic,but the formation mechanisms remain controversial.A high-resolution 3 D velocity structure of crust and mantle is important for understanding the lithospheric deformation and deep dynamic process.A here we present a 3 D S-wave velocity structure of the crust and upper mantle in the Ordos Block and surrounding regions by joint inversion of receiver functions and surface wave data from a dense broadband seismic deployment.The lithosphere of the Ordos Block exhibits an obvious highvelocity anomaly.In the east and north of the Ordos and the southwestern part of the Tibetan Plateau,obvious low-velocity anomalies are detected in the upper mantle and extend into the Ordos.The lithosphere of the Ordos Block is thick in the center and thin at the edge,while the crust is relatively thin in the center and thick in the southwest and northeast.The crustal thickness of the tensional basin in the north is greater than that in the central Ordos.We suggest that the outward expansion of the mantle thermal materials in eastern Tibet and the upper mantle thermal upwelling in the eastern part of the North China Craton lead to the non-uniform lithospheric thinning,temperature rise and density reduction of the Ordos Block.The additional buoyancy and thermodynamic effects provided by them contributed to the continuous uplift of the Ordos Block since the Cenozoic.Influenced by the extrusion of Tibetan Plateau,the crustal thickening and rapid uplift occur in the southwestern and northern parts of the Ordos Block.The lithospheric structures of the Alxa and Ordos Blocks are different,and they may belong to different independent blocks before the Mesozoic.

关键词： Ordos North China Craton Lithospheric structure S-wave velocity structure Receiver function Surface wave

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政府数据开放生态系统如何驱动数据要素市场化发展——基于模糊集定性比较分析

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情报资料工作 2024年第3期45卷 78-85页

作者：宋世俊王浩先钟慧西南财经大学公共管理学院成都611130

[目的/意义]推进政府数据开放是加快培育数据要素市场化发展的重要抓手,如何优化政府数据开放生态以推动数据要素市场化发展是政府和学术界关注的焦点。[方法/过程]基于政府数据开放生态系统理论,运用模糊集定性比较分析方法,以我国16个... 详细信息

[目的/意义]推进政府数据开放是加快培育数据要素市场化发展的重要抓手,如何优化政府数据开放生态以推动数据要素市场化发展是政府和学术界关注的焦点。[方法/过程]基于政府数据开放生态系统理论,运用模糊集定性比较分析方法,以我国16个省(自治区、直辖市)为案例,探究政府数据开放生态中的准备度、平台层、数据层和利用层与数据要素市场化发展的联动效应。[结果/结论](1)政府数据开放系统中单一层面的发展不足以制约数据要素市场化发展;(2)存在2条驱动数据要素市场化高水平发展的路径:准备度和数据层支持下的平台层驱动型路径、准备度和数据层支持下的利用层驱动型路径;(3)存在1条非数据层和非利用层支持下非准备度驱动的数据要素市场化非高水平发展的路径,且与数据要素市场化高水平发展的驱动路径存在非对称关系。

关键词：政府数据开放生态系统数据要素市场化模糊集定性

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鉴别性特征学习模型实现跨摄像头下行人即时对齐

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计算机辅助设计与图形学学报 2019年第4期31卷 602-611页

作者：余春艳钟诗俊福州大学数学与计算机科学学院福州350116

为解决由于采用延后的关联算法而造成目标错误匹配和子序列漏匹配的问题,提出一种使用鉴别性特征学习模型实现跨摄像头下行人即时对齐的方法.首先基于孪生网络模型整合行人分类和行人身份鉴别模型,仅通过目标行人的单帧信息就可习得具... 详细信息

为解决由于采用延后的关联算法而造成目标错误匹配和子序列漏匹配的问题,提出一种使用鉴别性特征学习模型实现跨摄像头下行人即时对齐的方法.首先基于孪生网络模型整合行人分类和行人身份鉴别模型,仅通过目标行人的单帧信息就可习得具有良好鉴别性的行人外观特征,完成行人相似性值计算;其次提出跨摄像头行人即时对齐模型,根据行人外观、时序和空间3个方面的关联适配度实时建立最小费用流图并求解.实验结果表明,在行人重识别数据集Market-1501和CUHK03上,行人分类和身份鉴别模型的融合能显著提升特征提取的有效性且泛化能力良好,性能全面优于Gate-SCNN与S-LSTM方法;进一步地,在非重叠区域的跨摄像头行人跟踪的基准数据集NLPR_MCT上,该方法的行人即时关联精度比2014年ECCV跨摄像头行人跟踪冠军的延后关联算法高出了3.3%,仅次于当前最高精度算法6.6%,应用于跨摄像头跟踪时,跟踪精度亦超过当前的大部分算法.

关键词：行人即时对齐鉴别性特征学习模型卷积孪生网络

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面向显著性目标检测的SSD改进模型

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电子与信息学报 2018年第11期40卷 2554-2561页

作者：余春艳徐小丹钟诗俊福州大学数学与计算机科学学院福州350108

传统显著性目标检测方法常假设只有单个显著性目标,其效果依赖显著性阈值的选取,并不符合实际应用需求。近来利用目标检测方法得到显著性目标检测框成为一种新的解决思路。SSD模型可同时精确检测多个不同尺度的目标对象,但小尺寸目标检... 详细信息

传统显著性目标检测方法常假设只有单个显著性目标,其效果依赖显著性阈值的选取,并不符合实际应用需求。近来利用目标检测方法得到显著性目标检测框成为一种新的解决思路。SSD模型可同时精确检测多个不同尺度的目标对象,但小尺寸目标检测精度不佳。为此,该文引入去卷积模块与注意力残差模块,构建了面向多显著性目标检测的DAR-SSD模型。实验结果表明,DAR-SSD检测精度显著高于SOD模型;相比原始SSD模型,在小尺度和多显著性目标情形下性能提升明显;相比MDF和DCL等深度学习框架下的方法,也体现了复杂背景情形下的良好检测性能。

关键词：目标检测显著性目标检测去卷积注意力残差

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北京及周边地区震群活动研究

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地震地磁观测与研究 2023年第S1期44卷 211-213页

作者：王薇岳晓媛钟世军北京市地震局北京100080

1研究背景。震群是地震活动的一种形式,它的发生和发展与地下物质运动、应力状态、局部地区的构造条件和介质特性均相关(朱传镇等,1981)。受到外部作用后,断层应力增加或发震断层强度降低易导致震群的发生(Shelly et al,2016),其形成可... 详细信息

1研究背景。震群是地震活动的一种形式,它的发生和发展与地下物质运动、应力状态、局部地区的构造条件和介质特性均相关(朱传镇等,1981)。受到外部作用后,断层应力增加或发震断层强度降低易导致震群的发生(Shelly et al,2016),其形成可能受到了大范围构造应力的制约。一些大震来临之前,在相当广阔的区域内,常出现异常的震群活动(朱传镇等,1981;林邦慧等,1994;宋治平等,2001;李冬梅等,2011)。

关键词：首都圈北京震群地震活动性地震预测

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融合去卷积与跳跃嵌套结构的显著性区域检测

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计算机辅助设计与图形学学报 2018年第11期30卷 2150-2158页

作者：余春艳徐小丹钟诗俊福州大学数学与计算机科学学院福州350116

针对深度学习的显著性区域检测方法大多存在的显著性图边界信息丢失、轮廓模糊等问题,提出将全局嵌套边缘检测(HED)模型迁移至显著性区域检测任务以增强边界检测,在其基础网络结构之上融入去卷积模块与跳跃嵌套结构,构建了面向显著性区... 详细信息

针对深度学习的显著性区域检测方法大多存在的显著性图边界信息丢失、轮廓模糊等问题,提出将全局嵌套边缘检测(HED)模型迁移至显著性区域检测任务以增强边界检测,在其基础网络结构之上融入去卷积模块与跳跃嵌套结构,构建了面向显著性区域检测的HED-DSN模型.首先利用去卷积模块以乘积的方式结合底层与高层信息,然后利用跳跃嵌套结构以通道连接的方式将不同层次的特征进行融合,最后用全连接条件随机场对预测得到的显著性图进行优化.在MSRA-B, ECSSD, HKU-IS, SOD和DUT-OMRON共5个数据集上进行实验及模型评价,结果表明,HED-DSN模型在各数据集上均表现良好,不仅能准确地定位出显著性区域,且检测出的区域完整、边界清晰;在客观指标上,该模型的总体性能优于目前最好的DSS模型,且在SOD数据集上提高了近0.7%.

关键词：显著性区域检测端到端去卷积跳跃嵌套结构全连接条件随机场

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Toward Improving Protein-Ligand Binding Energy Computation

Toward Improving Protein-Ligand Binding Energy Computation

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第五届全国生物信息学与系统生物学学术大会暨国际生物信息...

作者： shijun zhong School of Life Science and Technology Dalian University of Technology

Background:Protein-ligand interaction plays a key role in controlling biological processes.Thus the computation of protein-ligand binding energy is a crucial step in computer aided drug discovery.Due to the huge amount of computational tasks in virtual screening and the complexity of protein-ligand systems,scoring functions with a lot of approximations are used other than accurate free energy approaches.This lets to low hit-to-lead rate. Methods:Quantum chemistry computations with new Gaussian basis sets and molecular dynamics simulations with the force field of drug molecules were used to improve the accuracy of protein-ligand binding energy computation.Scaling approaches were also used with respect to the ligand binding selectivity and molecular properties of drug-like compounds. Results:The accuracy of protein-ligand binding energy computation can be improved by introducing quantum chemistry correction and proper scaling. Conclusions:Higher accuracy of protein-ligand binding energy computation will be used to improve the efficiency of computer-aided drug design.

关键词： protein-ligand interaction binding energy computational accuracy drug design

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Fragmental Protein-peptide Docking

Fragmental Protein-peptide Docking

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2019中国化学会第十五届全国计算（机）化学学术会议

作者：孙璐 shijun zhong 大连理工大学 School of Bioengineering Dalian University of Technology

Protein-peptide interactions are crucial for various important cellular regulations [1]. Among the experimentally solved protein structures, i.e. the Protein Data Bank(PDB, ***), the protein-peptide complexes only pose a very low percent, about 7%. It is necessary to generate and predict the most of protein-peptide binding modes using computational methods like molecular docking [2]. However, compared to small molecules, peptides have higher flexibility and larger number of rotatable bonds, which is a big challenge for protein-peptide docking [2, 3]. For long peptides, full conformation sampling is very time-consuming, and the peptide changes greatly before and after binding to the proteins [4]. Small molecule docking programs have a good performance in processing short peptides [4, 5]. Therefore, we divide a long peptide into short peptides, and then use small molecule docking program to dock each short peptide with protein at the same time, finally link the conformation of the docked peptide to a complete peptide in turn. We use a divide-and-conquer approach which contains the parallel docking of peptide fragments and their connection. Multiple peptide conformations can be generated in a short time and reasonable conformations can be identified. This algorithm was tested on the LEADS-PEP benchmark data set of 36 diverse complexes with peptides of 6-12 residues. Some issues related to this method are compared including the calculation time, the number of amino acid residues, and two docking tools AutoDock Vina[6] and LeDock(http://***) [7].

关键词： peptide-protein interactions molecular docking AutoDock Vina LeDock fragments

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Binding Modes of Potential Varic Acid Inhibitors on PTP1B

Binding Modes of Potential Varic Acid Inhibitors on PTP1B

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2019中国化学会第十五届全国计算（机）化学学术会议

作者：赵丹 shijun zhong 大连理工大学 School of Bioengineering Dalian University of Technology

Protein tyrosine phosphatase 1 B（PTP1 B） is considered as a negative regulator of insulin signaling and an important target for the treatment of type II diabetes and obesity. Inhibition of PTP1 B can enhance insulin signaling[1]. A series of varic acid analogues were reported as PTP1 B inhibitors[2]. We investigate the binding modes and inhibition mechanisms of these inhibitors using molecular docking, molecular dynamics simulations and MM/GBSA binding free energy decomposition analysis. After re-docking validation of three docking programs（Auto Dock Vina[3], LeDock[4] and DOCK[5]）, the binding poses of AutoDock Vina and LeDock programs were selected as the initial conformations of subsequent MD simulation. Based on the binding free energy of MM/GBSA, the most favorable binding mode of each inhibitor was determined. According to the results of multi-copy binding free energy, the rank of calculated binding free energies（ΔGbind） of these inhibitors is in excellent agreement with that of experimental bioactivity data（IC50）. The correlation coefficient between the MM/GBSA results and experimental binding data was 0.95. The electrostatic energy is dominated component of the total energy. Although these six compounds have similar chemical structures, their binding modes and binding mechanisms are different. The monocyclic molecules（compound 1-3） have significant interactions with residues from Cys215 to Arg221. The bicyclic molecules（compound 4-5） can form hydrogen bonds with ASP48 or Glu115. The tricyclic molecule（compound 6） shows strongest binding affinity because it occupies both the active site（P loop） and the secondary binding site. Based on the structure of compound 6, 17 derivatives were designed and calculated using molecular docking and MD simulation. Among them, 8 derivatives have stronger binding ability with PTP1 B and can be suggested as the varic acid inhibitors for experimental validation.

关键词： PTP1B inhibitors binding modes molecular docking molecular dynamics simulation binding free energy

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