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Machine learning-aided atomic structure identification of interfacial ionic hydrates from AFM images

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National Science Review 2023年第7期10卷 114-123页

作者： Binze Tang yizhi song Mian Qin Ye Tian Zhen Wei Wu Ying Jiang Duanyun Cao Limei Xu International Center for Quantum Materials Peking University School of Physics Peking University Institute of Nonequilibrium Systems School of Systems Science Beijing Normal University Collaborative Innovation Center of Quantum Matter CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials Peking University Beijing Key Laboratory of Environmental Science and Engineering School of Materials Science and Engineering Beijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center

Relevant to broad applied fields and natural processes,interfacial ionic hydrates have been widely studied by using ultrahigh-resolution atomic force microscopy(AFM).However,the complex relationship between the AFM signal and the investigated system makes it difficult to determine the atomic structure of such a complex system from AFM images alone.Using machine learning,we achieved precise identification of the atomic structures of interfacial water/ionic hydrates based on AFM images,including the position of each atom and the orientations of water mole cules.Furthermore,it was found that structure prediction of ionic hydrates can be achieved cost-effectively by transfer learning using neural network trained with easily available interfacial water data.Thus,this work provides an efficient and economical methodology that not only opens up avenues to determine atomic structures of more complex systems from AFM images,but may also help to interpret other scientific studies involving sophisticated experimental results.

关键词： machine learning transfer learning atomic force microscopy atomic scale structure identification interfacial ion hydrates

A three-stage real-time detector for traffic signs in large panoramas

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Computational Visual Media 2019年第4期5卷 403-416页

作者： yizhi song Ruochen Fan Sharon Huang Zhe Zhu Ruofeng Tong Department of Computer Science Purdue University305 N.University StreetWest LafayetteIN 47907USA Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China College of Information Sciences and Technology Penn State UniversityUniversity ParkPA 16802USA Department of Radiology Duke UniversityDurhamNC 27705USA College of Computer Science and Technology Zhejiang UniversityHangzhou 310007China

Traffic sign detection is one of the key components in autonomous driving.Advanced autonomous vehicles armed with high quality sensors capture high definition images for further analysis.Detecting traffic signs,moving vehicles,and lanes is important for localization and decision making.Traffic signs,especially those that are far from the camera,are small,and so are challenging to traditional object detection methods.In this work,in order to reduce computational cost and improve detection performance,we split the large input images into small blocks and then recognize traffic signs in the blocks using another detection module.Therefore,this paper proposes a three-stage traffic sign detector,which connects a Block Net with an RPN–RCNN detection network.Block Net,which is composed of a set of CNN layers,is capable of performing block-level foreground detection,making inferences in less than 1 ms.Then,the RPN–RCNN two-stage detector is used to identify traffic sign objects in each block;it is trained on a derived dataset named TT100 KPatch.Experiments show that our framework can achieve both state-of-the-art accuracy and recall;its fastest detection speed is 102 fps.

关键词： traffic sign detection real time

Microbial community and functional genes in the rhizosphere of alfalfa in crude oil-contaminated soil

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Frontiers of Environmental Science & Engineering 2012年第6期6卷 797-805页

作者： YiZHONG Jian WANG yizhi song Yuting LIANG Guanghe LI School of Environment Tsinghua UniversityBeijing 100084China State Key Joint Laboratory of Environmental Simulation and Pollution Control Tsinghua UniversityBeijing 100084China

A rhizobox system constructed with crude oil- contaminated soil was vegetated with alfalfa （Medicago sativa L.） to evaluate the rhizosphere effects on the soil microbial population and functional structure, and to explore the potential mechanisms by which plants enhance the removal of crude oil in soil. During the 80-day experiment, 31.6% of oil was removed from the adjacent rhizosphere （AR）; this value was 27% and 53% higher than the percentage of oil removed from the far rhizosphere （FR） and from the non-rhizosphere （NR）, respectively. The populations of heterotrophic bacteria and hydrocarbon- degrading bacteria were higher in the AR and FR than in the NR. However, the removal rate of crude oil was positively correlated with the proportion of hydrocarbon- degrading bacteria in the rhizosphere. In total, 796, 731, and 379 functional genes were detected by microarray in the AR, FR, and NR, respectively. Higher proportions of functional genes related to carbon degradation and organic remediation, were found in rhizosphere soil compared with NR soil, suggesting that the rhizosphere selectively increased the abundance of these specific functional genes. The increase in water-holding capacity and decrease in pH as well as salinity of the soil all followed the order of AR 〉 FR 〉 NR. Canonical component analysis showed that salinity was the most important environmental factor influencing the microbial functional structure in the rhizosphere and that salinity was negatively correlated with the abundance of carbon and organic degradation genes.

关键词： crude oil-contaminated soil phytoremedia-tion rhizosphere effects rhizobox functional genes

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创伤性脑损伤及其治疗药物

沈阳药科大学学报 2024年第3期41卷 397-408页

作者：张怡之宋兴爽李祺黄欣杜丽娜山东中医药大学药学院山东济南250355 军事科学院军事医学研究院辐射医学研究所北京100850 军事科学院军事医学研究院军事认知与脑科学研究所北京100850

创伤性脑损伤(traumatic brain injury,TBI)是一种威胁人类生命安全的常见损伤。由于其损伤机制复杂,目前外科手术是临床首选治疗手段,但针对手术后继发性TBI的预防与治疗尚没有有效治疗药物。研究TBI损伤机制、寻找有效治疗药物以减轻... 详细信息

创伤性脑损伤(traumatic brain injury,TBI)是一种威胁人类生命安全的常见损伤。由于其损伤机制复杂,目前外科手术是临床首选治疗手段,但针对手术后继发性TBI的预防与治疗尚没有有效治疗药物。研究TBI损伤机制、寻找有效治疗药物以减轻患者痛苦、提高生活质量,成为目前的研究热点。本综述概括了近几年有关TBI治疗的最新进展,包括TBI损伤机制、TBI动物模型建立和评价指标、治疗药物及其新型递送系统,其中新型药物递送系统概括了聚合物纳米粒、水凝胶、树枝状聚合物、脂质体、胶束和细胞外囊泡作为新型药物载体在TBI治疗中的应用,希望为安全、有效地治疗TBI提供新思路。

关键词：创伤性脑损伤损伤机制药物递送系统动物模型

氧化铈纳米酶-甲基丙烯酸酐化明胶水凝胶在小鼠全层皮肤缺损感染创面修复中的作用

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中华烧伤与创面修复杂志 2024年第2期40卷 131-140页

作者：顾雅男徐翔昊王彦平李宇韬梁振余州彭毅志宋保强西安医学院西安710021 空军军医大学第一附属医院整形科西安710032 陆军军医大学(第三军医大学)第一附属医院全军烧伤研究所创伤与化学中毒全国重点实验室重庆400038

目的探讨氧化铈纳米酶-甲基丙烯酸酐化明胶(GelMA)水凝胶(以下简称复合水凝胶)在小鼠全层皮肤缺损感染创面修复中的作用。方法该研究为实验研究。采用水热法制备粒径为(116±9)nm的氧化铈纳米酶,同时制备具有多孔网状结构且成胶性能良好... 详细信息

目的探讨氧化铈纳米酶-甲基丙烯酸酐化明胶(GelMA)水凝胶(以下简称复合水凝胶)在小鼠全层皮肤缺损感染创面修复中的作用。方法该研究为实验研究。采用水热法制备粒径为(116±9)nm的氧化铈纳米酶,同时制备具有多孔网状结构且成胶性能良好的GelMA水凝胶。筛选出25μg/mL氧化铈纳米酶可明显促进人皮肤成纤维细胞增殖和具有较高的超氧化物歧化酶活性,将其加入GelMA水凝胶中制备复合水凝胶。计算用磷酸盐缓冲液(PBS)浸泡3、7 d后复合水凝胶中氧化铈纳米酶的释放百分比。将小鼠红细胞悬液分为用相应溶液处理的PBS组、Triton X-100组、氧化铈纳米酶组、GelMA水凝胶组及复合水凝胶组,利用酶标仪检测处理1 h后红细胞的溶血情况。测定用PBS、氧化铈纳米酶、GelMA水凝胶及复合水凝胶培养耐甲氧西林金黄色葡萄球菌(MRSA)和大肠埃希菌2 h后的细菌浓度。以上实验样本数均为3。取24只8周龄雄性BALB/c小鼠,在背部对称位置各制备1个用MRSA感染的全层皮肤缺损创面。将小鼠分为不进行药物干预的对照组及滴加相应溶液的氧化铈纳米酶组、GelMA水凝胶组和复合水凝胶组,每组6只小鼠。观察伤后3、7、14 d创面愈合情况并测量伤后3、7 d剩余创面面积(样本数为5)。取小鼠伤后3 d创面分泌物,检测MRSA的浓度(样本数为3),采用激光散斑血流成像系统观测小鼠伤后5 d创面血流灌注量(样本数为6)。伤后14 d,取小鼠创面组织,行苏木精-伊红染色观察新生上皮情况,行Masson染色观察胶原情况(样本数均为3)。结果浸泡3、7 d后,复合水凝胶中氧化铈纳米酶释放百分比分别约为39%、75%。处理1 h后,与Triton X-100组比较,PBS组、GelMA水凝胶组、氧化铈纳米酶组及复合水凝胶组红细胞溶血程度均明显下降(P0.05)。伤后3 d,复合水凝胶组小鼠创面MRSA浓度明显低于对照组、氧化铈纳米酶组、GelMA水凝胶组(P值均<0.05)。伤后5 d,复合水凝胶组小鼠创面血液灌注量明显大于对照组、氧化铈纳米酶组、GelMA水凝胶组(P值均<0.05)。伤后14 d,复合水凝胶组小鼠创面基本完成上皮化,上皮化情况明显优于其他3组;复合水凝胶组小鼠创面胶原含量较其他3组明显增多,排列也更为有序。结论复合水凝胶具有良好的生物相容性和体内外抗菌效果,可持续缓释氧化铈纳米酶,改善早期创面血流灌注,促进创面再上皮化及胶原合成,从而促进小鼠全层皮肤缺损感染创面愈合。

关键词：生物相容性材料水凝胶感染氧化铈纳米酶甲基丙烯酸酐化明胶创面修复

肉豆蔻精油/羟丙基-β-环糊精包合物对冷鲜猪肉的保鲜效果

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食品与发酵工业 2024年第10期50卷 187-196页

作者：席小辉胡瑜文张升阳宋欠欠黄轩宇金懿志刘爱冰李诚胡滨四川农业大学食品学院四川雅安625000

为研究肉豆蔻精油/羟丙基-β-环糊精(nutmeg essential oil/hydroxypropyl-β-cyclodextrin,NEO/HP-β-CD)包合物对冷鲜猪肉的保鲜效果,采用不同浓度的包合物结合浸泡法、涂抹法和无纺布法处理冷鲜猪肉,每隔2 d测定菌落总数、pH、挥发... 详细信息

为研究肉豆蔻精油/羟丙基-β-环糊精(nutmeg essential oil/hydroxypropyl-β-cyclodextrin,NEO/HP-β-CD)包合物对冷鲜猪肉的保鲜效果,采用不同浓度的包合物结合浸泡法、涂抹法和无纺布法处理冷鲜猪肉,每隔2 d测定菌落总数、pH、挥发性盐基氮、硫代巴比妥酸值、质构、汁液流失率、色泽与感官指标。结果表明,NEO/HP-β-CD包合物添加量1%的无纺布法可有效降低贮藏过程中冷鲜猪肉的菌落总数、pH值、挥发性盐基氮含量,延缓猪肉质构特性与色泽劣变,提高感官品质;与对照组(6 d)相比,可延长贮藏期4 d。因此,NEO/HP-β-CD包合物添加量1%的无纺布法对冷鲜猪肉具有较好的保鲜效果。

关键词：肉豆蔻精油/羟丙基-β-环糊精包合物冷鲜猪肉保鲜效果指标测定

几种功能性物质抑制产肠毒性大肠杆菌的效果及作用机制研究

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中国兽医科学 2024年第5期54卷 696-701页

作者：黄一智宋转童庆芳张艺王露李中华吴涛侯永清武汉轻工大学动物营养与饲料科学湖北省重点实验室湖北武汉430023 武汉轻工大学动物营养与饲料安全湖北省协同创新中心湖北武汉430023 武汉市江夏区动物疫病预防控制中心湖北武汉430072

不同浓度葛根素(PR)、丙酮酸乙酯(EP)、酪醇(TS)、氧化锌(ZnO)处理IPEC-1细胞,CCK-8法检测细胞活力;乳酸脱氢酶(lactate dehydrogena,sLeDH)试剂盒检测几种功能性物质对ETEC K88感染IPEC-1细胞损伤程度的影响;实时荧光定量PCR法检测不... 详细信息

不同浓度葛根素(PR)、丙酮酸乙酯(EP)、酪醇(TS)、氧化锌(ZnO)处理IPEC-1细胞,CCK-8法检测细胞活力;乳酸脱氢酶(lactate dehydrogena,sLeDH)试剂盒检测几种功能性物质对ETEC K88感染IPEC-1细胞损伤程度的影响;实时荧光定量PCR法检测不同功能性物质对ETEC K88感染IPEC-1细胞相关基因相对表达水平的影响。结果:PR、EP和ZnO均可促进IPEC-1细胞增殖,其最适添加浓度分别为5μmol/L、1 mmol/L和1μmol/L;TS无促进IPEC-1细胞增殖作用。ETEC K88感染IPEC-1细胞后导致LDH活性显著升高(P<0.05);与K88组相比,添加5μmol/L PR、1 mmol/L EP和1μmol/L ZnO均能显著降低LDH活性(P<0.05)。ETEC K88感染后引起白细胞介素-6(IL-6)、白细胞介素-8(IL-8)、肿瘤坏死因子-α(TNF-α)、趋化因子配体2(CXCL2)、热休克蛋白70(HSP70)和核因子E2相关因子(Nrf2)的相对表达量显著升高(P<0.05),细胞周期蛋白D(cyclin D)和绒毛蛋白(Villi)n基因的相对表达量显著降低(P<0.05)。PR显著提高了细胞IL-8和Villin基因的相对表达量(P<0.05);EP显著降低了(P<0.05)细胞TNF-α和CXCL2基因的相对表达量;ZnO显著提高了Villin和Cyclin D基因的相对表达量(P<0.05)。此外,PR、EP和ZnO均能降低大肠杆菌16S rRNA基因的相对表达量(P<0.05)。综上所述,PR、EP和ZnO均能抑制ETEC K88的增殖,具有抑菌效果,EP可以降低K88造成的炎性基因的表达,PR可以增加肠绒毛基因表达,ZnO可以增加细胞周期基因的表达。

关键词：功能性物质猪小肠上皮细胞产肠毒性大肠杆菌

基于边界组织和三螺旋理论的科技成果转化机构建设模式研究与启示

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中阿科技论坛（中英文） 2024年第2期 82-86页

作者：汪俊枫赵一智宋之杰杜旭虹浙江火炬生产力促进中心浙江杭州310012 燕山大学经济管理学院河北秦皇岛066004

当前,科研与产业脱节严重阻碍了我国科技创新和经济发展,探寻科技成果转化体制机制,打通“最后一公里”迫在眉睫。文章基于边界组织和三螺旋理论,构建包含三个发展层次和四种创建模式的科技成果转化机构三螺旋动态立体结构模型,并选取... 详细信息

当前,科研与产业脱节严重阻碍了我国科技创新和经济发展,探寻科技成果转化体制机制,打通“最后一公里”迫在眉睫。文章基于边界组织和三螺旋理论,构建包含三个发展层次和四种创建模式的科技成果转化机构三螺旋动态立体结构模型,并选取浙江省内具有代表性的案例,以辅助模型分析后提出了相关改进建议。研究发现,四种科技成果转化机构创建模式各有其特点、优劣势和适用条件,在推进科技成果转化过程中,应注重开展概念验证、强化产学研合作、加强科技金融支持等工作。

关键词：科技成果转化机构创建模式边界组织理论三螺旋理论

Metal-Free 12-Catalyzed Highly Selective Dehydrogenative Coupling of Alcohols and Cyclohexenones

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Chinese Journal of Chemistry 2018年第3期36卷 233-240页

作者： Yu-Feng Liang yizhi Yuan Tao Shen song song Ning Jiao State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China State Key Laboratory of Elemento-Organic Chemistry Nankai University Weijin Road 94 Tianjin 300071 China

The l2 catalyzed highly selective oxidatve condensation of cydohexenones and alcohols for the synthesis of aryl atkyl ethers has been described. DMSO is employed as the mild terminal oxidant. This novel methodology offers a metal-free reaction condition, operational simplicity and broad substrate scope to afford valuable products from inexpensive reagents. Various meta-substituted aromatic ethers which are hardly synthesized from the reported methods requiring meta-substituted phenols, are efficiently prepared by the present protocol.

关键词： metal-free dehydrogenative coupling oxidation selectivity alcohols