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Highly Dynamic Polynuclear Metal Cluster Revealed in a Single Metallothionein Molecule

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Research 2021年第1期2021卷 620-630页

作者： guodong yuan Felipe Curtolo Yibing Deng Tao Wu Fang Tian Qun Ma Yutong Liu Jinglin Zuo Guilherme Menegon Arantes Peng Zheng State Key Laboratory of Coordination Chemistry Chemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu 210023China Department of Biochemistry Instituto de QuímicaUniversidade de São PauloAv.Prof.Lineu Prestes 74805508-900 São PauloSPBrazil

Human metallothionein(MT)is a small-size yet efficient metal-binding protein,playing an essential role in metal homeostasis and heavy metal *** contains two domains,each forming a polynuclear metal cluster with an exquisite hexatomic ring *** apoprotein is intrinsically disordered,which may strongly influence the clusters and the metal-thiolate(M-S)bonds,leading to a highly dynamic ***,these features are challenging to identify due to the transient nature of these *** individual signal from dynamic conformations with different states of the cluster and M-S bond will be averaged and blurred in classic ensemble *** circumvent these problems,we combined a single-molecule approach and multiscale molecular simulations to investigate the rupture mechanism and chemical stability of the metal cluster by a single MT molecule,focusing on the Zn4S11 cluster in theαdomain upon *** multiple unfolding pathways and intermediates are observed for both domains,corresponding to different combinations of M-S bond *** of the pathways is clearly preferred suggesting that unfolding proceeds from the distribution of protein conformational substates with similar M-S bond *** indicate that the metal cluster may rearrange,forming and breaking metal-thiolate bonds even when MT is folded independently of large protein backbone ***,a highly dynamic polynuclear metal cluster with multiple conformational states is revealed in MT,responsible for the binding promiscuity and diverse cellular functions of this metal-carrier protein.

关键词： structure cluster bonds

AHMT分光光度法测定室内空气中甲醛的试验条件改进研究

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当代化工研究 2024年第3期 64-66页

作者：刘梦迪姜振军袁国栋陈瑶佳张钰国南京市产品质量监督检验院(南京市质量发展与先进技术应用研究院) 江苏211100

甲醛检测结果的准确性直接关系到人民群众的健康,2020年GB 50325—2020《民用建筑工程室内环境污染控制规范》正式将AHMT分光光度法修改为仲裁法。目前,有多项研究显示该方法的试验条件会影响到甲醛检测结果的准确性,而且检测的结果与... 详细信息

甲醛检测结果的准确性直接关系到人民群众的健康,2020年GB 50325—2020《民用建筑工程室内环境污染控制规范》正式将AHMT分光光度法修改为仲裁法。目前,有多项研究显示该方法的试验条件会影响到甲醛检测结果的准确性,而且检测的结果与人民群众的健康是息息相关的。在此基础上,项目组主要通过改进AHMT分光光度法的试验条件,优化试验吸收液的稳定性、显色剂用量、显色剂的反应时间、显色剂的反应温度等影响因素,并验证了检出限、精密度和准确度。

关键词：甲醛 AHMT分光光度法条件优化

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饱和石灰水涂层对玉米芯炭碳固存能力的影响

西南大学学报（自然科学版） 2024年第3期46卷 125-134页

作者：校亮李文瀚吴静华袁国栋陈思洁李悦诗徐青陈满洪陈啟林肇庆学院广东省环境健康与资源利用重点实验室/广东省水土污染管控与装备智能制造工程技术研究中心广东肇庆526061 广东浦特农业发展有限公司广东肇庆526074 广州绿石碳科技股份有限公司广州510630

生物质炭作为一种富碳多孔材料,具有固碳、培肥和减污等多重功效,目前面临着产量有限和成本昂贵的突出问题.将生物质就地炭化和应用可解决上述问题,而如何实现限氧是其核心.以玉米芯为原材料,通过饱和石灰水涂层包覆实现生物质“自限氧... 详细信息

生物质炭作为一种富碳多孔材料,具有固碳、培肥和减污等多重功效,目前面临着产量有限和成本昂贵的突出问题.将生物质就地炭化和应用可解决上述问题,而如何实现限氧是其核心.以玉米芯为原材料,通过饱和石灰水涂层包覆实现生物质“自限氧”,以“水-火联动”方法成炭,探讨暴露时间和饱和石灰水涂层对玉米芯在炭化过程中碳固存能力的影响.结果表明:随暴露时间延长,玉米芯炭的碳含量、比表面积及官能团(—COOH和phenolic—OH)含量均逐渐降低,以0 min暴露时间炭的碳转化率最大(45.17%);饱和石灰水涂层下其碳转化率进一步提升至92.60%;涂层包覆壳通过物理阻隔产生的“自限氧”作用及其所含的Ca^(2+)以离子架桥、络合或π电子作用增强了碳截留量.“水-火联动”和饱和石灰水涂层技术的成炭过程为玉米芯在曝氧环境下的“包覆壳限氧-水淬灭”高温热裂解过程.期间,Ca^(2+)或可通过多种方式阻止C=O,O=C—O键断裂生成气体CO_(x)以提高碳截留量并优化碳骨架结构.

关键词：碳截留水-火联动石灰水暴露时间玉米芯

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网络舆情危机演变特征及其预警方案研究

现代情报 2021年第7期41卷 154-159页

作者：袁国栋重庆市委党校重庆400041

[目的/意义]采用当前方法分析网络舆情危机演变特征时,无法明确网络舆情传播过程中演变特征影响因素之间的因果关系,导致分析结果的灰色关联度低、小误差概率小、均方差比大,因此研究了网络舆情危机演变特征及其预警方案创新方法,采用... 详细信息

[目的/意义]采用当前方法分析网络舆情危机演变特征时,无法明确网络舆情传播过程中演变特征影响因素之间的因果关系,导致分析结果的灰色关联度低、小误差概率小、均方差比大,因此研究了网络舆情危机演变特征及其预警方案创新方法,采用系统动力学对网络舆情危机演变变量和影响因素进行仿真和建模,获取网络舆情危机演变的主要影响因素,结合网络舆情传播热度与各因素之间的因果关系分析网络舆情传播系统。[方法/过程]结合Verhulst模型和灰色理论模型构建灰色Verhulst预测模型,根据各影响因素之间存在的因果关系分析网络舆情危机演变特征,根据分析结果提出构建信息汇集分析机制、预警机制、信息发布机制和引导机制的预警方案。[结果/结论]实验结果表明,采用所提方法分析网络舆情危机演变特征时,分析结果的灰色关联度高、小误差概率大、均方差比小。

关键词：网络舆情危机演变特征灰色Verhulst预测模型预警方案

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奥氏体系复合钢板的焊接工艺

焊接 2006年第5期 51-54页

作者：原国栋北京兴创投资有限公司 102600

通过对奥氏体系复合钢板焊接工艺评定、焊接工艺编制、焊工培训、焊接质量检验、酸洗-钝化处理等环节的试验和实施,解决了奥氏体系复合钢板焊接技术和与此相关的一些生产技术难题,圆满地制成了奥氏体系复合钢板产品。

关键词：复合钢板焊接工艺焊接工艺评定

The mechanosensitive lncRNA Neat1 promotes osteoblast function through paraspeckle-dependent Smurf1 mRNA retention

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Bone Research 2022年第2期10卷 338-353页

作者： Caizhi Liu Xingcheng Gao Yuheng Li Weijia Sun Youjia Xu Yingjun Tan Ruikai Du Guohui Zhong Dingsheng Zhao Zizhong Liu Xiaoyan Jin Yinlong Zhao Yinbo Wang Xinxin yuan Junjie Pan guodong yuan Youyou Li Wenjuan Xing Guanghan Kan Yanqing Wang Qi Li Xuan Han Jianwei Li Shukuan Ling Yingxian Li State Key Laboratory of Space Medicine Fundamentals and Application China Astronaut Research and Training CenterBeijingChina The Key Laboratory of Aerospace Medicine Ministry of EducationThe Fourth Military Medical UniversityXi’anShaanxiChina The Second Affiliated Hospital of Soochow University SuzhouJiangsuChina College of Life Sciences Hebei Normal UniversityShijiazhuangHebeiChina Medical College of Soochow University SuzhouJiangsuChina Medical School of Southeast University NanjingJiangsuChina

Mechanical stimulation plays an important role in bone remodeling. Exercise-induced mechanical loading enhances bone strength,whereas mechanical unloading leads to bone loss. Increasing evidence has demonstrated that long noncoding RNAs(lnc RNAs) play key roles in diverse biological, physiological and pathological contexts. However, the roles of lnc RNAs in mechanotransduction and their relationships with bone formation remain unknown. In this study, we screened mechanosensing lnc RNAs in osteoblasts and identified Neat1, the most clearly decreased lnc RNA under simulated microgravity. Of note, not only Neat1 expression but also the specific paraspeckle structure formed by Neat1 was sensitive to different mechanical stimulations, which were closely associated with osteoblast function. Paraspeckles exhibited small punctate aggregates under simulated microgravity and elongated prolate or larger irregular structures under mechanical loading. Neat1 knockout mice displayed disrupted bone formation, impaired bone structure and strength, and reduced bone mass. Neat1 deficiency in osteoblasts reduced the response of osteoblasts to mechanical stimulation. In vivo, Neat1 knockout in mice weakened the bone phenotypes in response to mechanical loading and hindlimb unloading stimulation. Mechanistically, paraspeckles promoted nuclear retention of E3 ubiquitin ligase Smurf1 m RNA and downregulation of their translation, thus inhibiting ubiquitination-mediated degradation of the osteoblast master transcription factor Runx2, a Smurf1 target. Our study revealed that Neat1 plays an essential role in osteoblast function under mechanical stimulation, which provides a paradigm for the function of the lnc RNA-assembled structure in response to mechanical stimulation and offers a therapeutic strategy for long-term spaceflight-or bedrest-induced bone loss and age-related osteoporosis.

关键词： stimulation mec impaired

MKEAH:Multimodal knowledge extraction and accumulation based on hyperplane embedding for knowledge-based visual question answering

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虚拟现实与智能硬件（中英文） 2024年第4期6卷 280-291页

作者： Heng ZHANG Zhihua WEI Guanming LIU Rui WANG Ruibin MU Chuanbao LIU Aiquan yuan guodong CAO Ning HU Tongji University Shanghai 2000092China Alibaba Group Shanghai 200030China

Background External knowledge representations play an essential role in knowledge-based visual question and answering to better understand complex scenarios in the open *** entity-relationship embedding approaches are deficient in representing some complex relations,resulting in a lack of topic-related knowledge and redundancy in topic-irrelevant *** To this end,we propose MKEAH:Multimodal Knowledge Extraction and Accumulation on *** ensure that the lengths of the feature vectors projected onto the hyperplane compare equally and to filter out sufficient topic-irrelevant information,two losses are proposed to learn the triplet representations from the complementary views:range loss and orthogonal *** interpret the capability of extracting topic-related knowledge,we present the Topic Similarity(TS)between topic and *** Experimental results demonstrate the effectiveness of hyperplane embedding for knowledge representation in knowledge-based visual question *** model outperformed state-of-the-art methods by 2.12%and 3.24%on two challenging knowledge-request datasets:OK-VQA and KRVQA,*** The obvious advantages of our model in TS show that using hyperplane embedding to represent multimodal knowledge can improve its ability to extract topic-related knowledge.

关键词： Knowledge-based visual question answering Hyperplane Topic-related

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基于单幅透视图像确定相机参数的几何方法

计算机研究与发展 2006年第11期43卷 1933-1938页

作者：袁国栋秦开怀胡伟清华大学计算机科学与技术系北京100084

提出一种求解相机内、外参数的几何方法.在不考虑相机镜头变形的前提下,首先根据空间平面上的单个矩形,从该矩形的两灭点透视图中,根据灭点间的几何关系,补出另外一个灭点的坐标;然后根据透视投影的灭点理论,计算出相机的相对位置;若已... 详细信息

提出一种求解相机内、外参数的几何方法.在不考虑相机镜头变形的前提下,首先根据空间平面上的单个矩形,从该矩形的两灭点透视图中,根据灭点间的几何关系,补出另外一个灭点的坐标;然后根据透视投影的灭点理论,计算出相机的相对位置;若已知矩形边的实际长度,可以恢复出相机在三维空间中的实际位置和矩形顶点的空间坐标;最后根据透视投影关系计算出相机的有效焦距.大量的模拟和真实实验表明,该方法简单、易于操作,具有标定精度高、鲁棒性强的优点.

关键词：相机标定灭点有效焦距长度

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原子力显微镜表征土壤中的纳米胶体

土壤学报 2009年第5期46卷 840-850页

作者：汤志云陈旸 guodong yuan 吴龙华章海波骆永明中国科学院土壤环境与污染修复重点实验室(南京土壤研究所) 南京210008 中国科学院研究生院北京100049 江苏省地质调查研究院测试研究所南京210018 南京大学地球科学系南京210093 Landcare Research Palmerston North 4442 New Zealand

以平均粒径和多分散性指数为参数、采用原子力显微镜(AFM)表征了不同地区三种土壤纳米胶体的粒径与形貌,研究了pH及重金属离子对纳米胶体粒径和形貌的影响。结果表明,江苏九华(JH-4)土壤纳米胶体主要为形状规则的黏土矿物粒子,并部分被... 详细信息

以平均粒径和多分散性指数为参数、采用原子力显微镜(AFM)表征了不同地区三种土壤纳米胶体的粒径与形貌,研究了pH及重金属离子对纳米胶体粒径和形貌的影响。结果表明,江苏九华(JH-4)土壤纳米胶体主要为形状规则的黏土矿物粒子,并部分被有机质包裹或覆盖,平均粒径为21.5nm(n=98),多分散性程度高(PI=1.9);浙江富阳(FY-1)土壤纳米胶体主要是无规则形状的有机质包裹的粒子,平均粒径为20.3nm(n=133),多分散性程度高(PI=2.0);江西德兴(DX-9)土壤纳米胶体主要是球状或近球状的无机粒子,平均粒径为56.3nm(n=147),多分散性程度较低(PI=1.3)。pH及重金属铜离子的存在对纳米胶体粒径和形貌会产生或分散或团聚的影响,这种影响可能与土壤纳米胶体的电荷性质、有机质含量等因素有关,形貌变化较为复杂。这种复杂性对理解和研究胶体在环境过程中的行为具有指导意义。

关键词：原子力显微镜(AFM) 土壤纳米胶体形貌