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Resolving aging dynamics of a 3D colloidal glass

Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 110-118页

作者： XiaoJuan Wang Jun Duan gan ding YunZhuo Lu Xing Lu LanHong Dai MinQiang Jiang State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Physical aging is an inherent property of glassy matter, but understanding its microscopic mechanism remains a challenge particularly at the particle level. In this work, we use a confocal microscope to in-situ trace the particle trajectories in a 3D colloidal glass for 73000 s, aiming at resolving the aging dynamics. By calculating the mean square displacement of particle motions, we find that the glass aging with time can be divided into three stages: β relaxation, α relaxation and free diffusion. The system's mean square displacement at each aging state is quantitatively resolved into three contributions of particle dynamics modes: vibration within the nearest-neighbor cages, hopping between cages and cooperative rearrangement. We further calculate the particle's free volume and find that the β-to-α transition is accompanied by the temporary increase of the system-averaged free volume due to pronounced hops of particles. Nevertheless, the temporal autocorrelation of the free volume spatial distribution still obeys a monotonically stretched exponential decay with an exponent of 0.76, which is related to the sub-diffusion dynamics of cooperative rearrangements and hops mixed in α relaxation. According to the resolved vibrational displacements,we calculate the vibrational density of states of this 3D glass, and the characteristic boson peak is reproduced at low *** findings shed insight into the particle-level aging dynamics of a real glass under purely thermal activation.

关键词： colloidal glass physical aging particle dynamics free volume boson peak

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Coupling of quasi-localized and phonon modes in glasses at low frequency

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Chinese Physics B 2024年第5期33卷 564-571页

作者：段军蔡松林丁淦戴兰宏蒋敏强 State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 101408China

Boson peak of glasses,a THz vibrational excess compared to Debye squared-frequency law,remains mysterious in condensed-matter physics and material *** appears in many different kinds of glassy matters and is also argued to exist in damped crystals.A consensus is that boson peak originates from the coupling of the(quasi)-localized non-phonon modes and the plane-wave-like phonon modes,but the coupling behavior is still not fully *** this paper,by modulating the content of localized modes and the frequencies of phonon modes,the coupling is clearly reflected in the localization and anharmonicity of low-frequency vibrational *** coupling enhances with increasing cooling rate and sample *** finite sample size,phonon modes do not fully intrude into the low frequency to form a dense spectrum and they are not sufficiently coupled to the localized modes,thus there is no Debye level and boson peak is *** suggestion remains valid in the presence of thermal motions induced by temperature,even though the anharmonicity comes into *** results point to the coupling of quasi-localized and phonon modes and its relation to the boson peak.

关键词： metallic glasses low-frequency vibrational modes plane wave boson peak

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miR-217靶向PI3K/Akt通路增强阿霉素对急性髓系白血病的敏感性

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中国实验血液学杂志 2024年第1期32卷 39-44页

作者：干定云吴军周曼陈婉姜雯武汉市第三医院血液内科湖北武汉430070

目的:探讨miR-217对急性髓系白血病细胞增殖及阿霉素敏感性的影响。方法:构建mimic NC和mi R-217 mimic载体转染至HL-60细胞中,q PCR检测转染效率。不同浓度的阿霉素处理细胞24和48 h,CCK-8法检测阿霉素化学敏感性并筛选阿霉素的最佳处... 详细信息

目的:探讨miR-217对急性髓系白血病细胞增殖及阿霉素敏感性的影响。方法:构建mimic NC和mi R-217 mimic载体转染至HL-60细胞中,q PCR检测转染效率。不同浓度的阿霉素处理细胞24和48 h,CCK-8法检测阿霉素化学敏感性并筛选阿霉素的最佳处理浓度和时间。将细胞分为对照、mimic NC、mi R-217 mimic、阿霉素和mi R-217 mimic+阿霉素共5组,流式细胞术检测细胞凋亡,qPCR检测miR-217、PI3K和Akt3的表达,Western blot检测PI3K/Akt通路蛋白PI3K、Akt3和凋亡蛋白Bcl-2、Bax的表达,双荧光素酶验证mi R-217和Akt3的关系。结果:mi R-217 mimic能够增强HL-60细胞对阿霉素的敏感性,阿霉素的最佳处理浓度和时间为160 ng/ml、48 h。与对照组相比,mi R-217 mimic组和阿霉素组细胞凋亡率、mi R-217和Bax蛋白水平显著升高(P<0.01),而Bcl-2蛋白和PI3K、Akt3 m RNA和蛋白水平显著降低(P<0.01);与阿霉素组相比,mi R-217 mimic+阿霉素组细胞凋亡率、mi R-217和Bax蛋白水平显著升高(P<0.01),Bcl-2蛋白和PI3K、Akt3 m RNA和蛋白水平显著降低(P<0.01)。双荧光素酶实验表明mi R-217与Akt3之间存在靶向调控关系。结论:mi R-217靶向Akt3调控PI3K/Akt通路,抑制细胞增殖,促进细胞凋亡并增强阿霉素对急性髓系白血病细胞的敏感性。

关键词： miR-217 急性髓系白血病阿霉素 PI3K/Akt通路

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Effective Energy Density of Glass Rejuvenation

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Acta Mechanica Solida Sinica 2022年第5期35卷 746-754页

作者： gan ding Feng Jiang Lanhong Dai Minqiang Jiang State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China

Glasses with rejuvenated structures usually exhibit improved room-temperature plasticity,which facilitates their ***,glass rejuvenation requires external energy injection to“shake up”the frozen-in disordered *** this work,we give the answer to how much the required energy *** to the constitutive model of amorphous plasticity,we find that the applied stress higher than the steady-state flow value can effectively induce the structural disordering in terms of the generation of free ***,the effective energy density(EED)of structural rejuvenation is defined as the integral of this effective stress on the corresponding *** tailoring the applied strain,strain rate,temperature and initial free volume,different degrees of structural rejuvenation are achieved,which show a generally linear correlation with the defined *** work deepens the understanding of glass rejuvenation from an energy perspective.

关键词： Glass Structural rejuvenation Effective energy density Shear transformations Free volume

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Unraveling the threshold stress of structural rejuvenation of metallic glasses via thermo-mechanical creep

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Science China(Physics,Mechanics & Astronomy) 2022年第6期65卷 101-109页

作者： gan ding Feng Jiang Xuan Song LanHong Dai MinQiang Jiang State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

The competition between physical aging and structural rejuvenation determines the physical and mechanical properties of glassy ***,the rejuvenation-aging boundary must be identified *** this work,we unravel a stress boundary to distinguish rejuvenation from aging via the thermo-mechanical creep of a typical Zr-based metallic *** crept glasses were rejuvenated into high-enthalpy disordered states when the applied stress exceeded a threshold that was numerically close to the steady-state flow stress;otherwise,the glasses were aged.A theoretical model for glass creep was adopted to demystify the observed stress threshold of *** model revealed that the thermo-mechanical creep beyond the threshold stress could activate sufficient shear transformations to create a net free volume,thus leading to structural ***,we derived the analytical expressions for the threshold and flow *** stresses can act as the rejuvenation-aging boundary,which is well supported by experimental creep *** present work procures a deeper understanding of the rejuvenation mechanism of glasses and provides useful implications for abstaining from glass aging.

关键词： metallic glass thermo-mechanical creep threshold stress shear transformations rejuvenation-aging boundary

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前四史先秦两汉人物自立自信自强人格品质研究

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边疆经济与文化 2024年第2期 98-102页

作者：姜徐淇丁敢真湖州师范学院教师教育学院浙江湖州313000

《史记》《汉书》《后汉书》《三国志》记载先秦两汉众多人物自立自信自强人格品质。修身自立的先秦两汉人物既有优秀的帝王也有崛起自平民中的优秀分子。修心自信的品质主要表现为“自恃自知,知人善用”“不惧磨难,自知坚毅”。修业自... 详细信息

《史记》《汉书》《后汉书》《三国志》记载先秦两汉众多人物自立自信自强人格品质。修身自立的先秦两汉人物既有优秀的帝王也有崛起自平民中的优秀分子。修心自信的品质主要表现为“自恃自知,知人善用”“不惧磨难,自知坚毅”。修业自强的品质主要表现为“坚韧不拔,意志坚定”“运筹帷幄,沉着冷静”“折而不挠,终成大业”。发掘和弘扬自立自信自强品质,有助于当代大学生的自我成长,有助于家庭教育不断改进,有助于中华民族伟大复兴。

关键词：自立自信自强前四史先秦两汉

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mIgM-mediated splenic marginal zone B cells targeting of folic acid for immunological evasion

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Acta Pharmaceutica Sinica B 2024年第2期14卷 808-820页

作者： Huan Wang Zhuxuan Jiang Zhiwei Guo gan Luo Tianhao ding Changyou Zhan Department of Pharmacology School of Basic Medical Sciences&Department of PharmacyShanghai Pudong HospitalFudan UniversityShanghai 200032China Department of Pharmaceutical Sciences School of PharmacyNaval Medical UniversityShanghai 200433China Shanghai Engineering Research Center for Synthetic Immunology Fudan UniversityShanghai 200032China

Folic acid is a fully oxidized synthetic folate with high bioavailability and stability which has been extensively prescribed to prevent congenital *** we revealed the immunosuppressive effect of folic acid by targeting splenic marginal zone B(MZB)*** acid demonstrates avid binding with the Fc domain of immunoglobulin M(IgM),targeting IgM positive MZB cells in vivo to destabilize IgM-B cell receptor(BCR)complex and block immune *** induced anergy of MZB cells by folic acid provides an immunological escaping window for *** conjugation of folic acid with therapeutic proteins and antibodies induces immunological evasion to mitigate the production of anti-drug antibodies,which is a major obstacle to the long-term treatment of biologics by reducing curative effects and/or causing adverse *** acid acts as a safe and effective immunosuppressant via IgM-mediated MZB cells targeting to boost the clinical outcomes of biologics by inhibiting the production of anti-drug antibodies,and also holds the potential to treat other indications that adverse immune responses need to be transiently shut off.

关键词： Membrane-bound IgM Anti-drugantibodies Bcell anergy Folic acid Marginal zoneBcells Bcell receptor Biologics Targeting

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Strongly Coupled Ag/Sn-SnO_(2)Nanosheets Toward CO_(2)Electroreduction to Pure HCOOH Solutions at Ampere‑Level Current

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Nano-Micro Letters 2024年第3期16卷 212-226页

作者： Min Zhang Aihui Cao Yucui Xiang Chaogang Ban Guang Han Junjie ding Li‑Yong gan Xiaoyuan Zhou College of Physics and Center of Quantum Materials and Devices Chongqing UniversityChongqing 401331People’s Republic of China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences(CAS)Fuzhou 350002People’s Republic of China College of Materials Science and Engineering Chongqing UniversityChongqing 400044People’s Republic of China Institute of New Energy Storage Materials and Equipment Chongqing 401135People’s Republic of China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044People’s Republic of China

Electrocatalytic reduction of CO_(2) converts intermittent renewable electricity into value-added liquid products with an enticing prospect,but its practical application is hampered due to the lack of high-performance ***,we elaborately design and develop strongly coupled nanosheets composed of Ag nanoparticles and Sn-SnO_(2) grains,designated as Ag/Sn-SnO_(2) nanosheets(NSs),which possess optimized electronic structure,high electrical conductivity,and more accessible *** a result,such a catalyst exhibits unprecedented catalytic performance toward CO_(2)-to-formate conversion with near-unity faradaic efficiency(≥90%),ultrahigh partial current density(2,000 mA cm^(−2)),and superior long-term stability(200 mA cm^(−2),200 h),surpassing the reported catalysts of CO_(2) electroreduction to ***,in situ attenuated total reflection-infrared spectra combined with theoretical calculations revealed that electron-enriched Sn sites on Ag/Sn-SnO_(2)NSs not only promote the formation of*OCHO and alleviate the energy barriers of*OCHO to*HCOOH,but also impede the desorption of H*.Notably,the Ag/Sn-SnO_(2)NSs as the cathode in a membrane electrode assembly with porous solid electrolyte layer reactor can continuously produce~0.12 M pure HCOOH solution at 100 mA cm^(−2)over 200 *** work may inspire further development of advanced electrocatalysts and innovative device systems for promoting practical application of producing liquid fuels from CO_(2).

关键词： Electrochemical CO_(2)reduction Coupled Ag/Sn-SnO_(2)nanosheets Electronic structure Porous solid electrolyte Pure

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Oral peptide therapeutics for diabetes treatment: State-of-the-art and future perspectives

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2006-2025页

作者： Bingwen ding Zhu Zhu Cong Guo Jiaxin Li Yong gan Miaorong Yu State Key Laboratory of Drug Research and Center of Pharmaceutics Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of Chinese Academy of Sciences Beijing 100049China School of Pharmacy Henan UniversityKaifeng 475004China NMPA Key Laboratory for Quality Research and Evaluation of Pharmaceutical Excipients National Institutes for Food and Drug ControlBeijing 100050China

Diabetes,characterized by hyperglycemia,is a major cause of death and disability ***,such as insulin and glucagon-like peptide-1(GLP-1)analogs,have shown promise as treatments for diabetes due to their ability to mimic or enhance insulin's actions in the *** to subcutaneous injection,oral administration of anti-diabetic peptides is a preferred ***,biological barriers significantly reduce the efficacy of oral peptide *** advancements in drug delivery systems and formulation techniques have greatly improved the oral delivery of peptide therapeutics and their efficacy in treating *** review will highlight(1)the benefits of oral anti-diabetic peptide therapeutics;(2)the biological barriers for oral peptide delivery,including pH and enzyme degradation,intestinal mucosa barrier,and biodistribution barrier;(3)the delivery platforms to overcome these biological ***,the review will discuss the prospects in this *** information provided in this review will serve as a valuable guide for future developments in oral anti-diabetic peptide therapeutics.

关键词： Oral peptides Diabetes Delivery platforms Insulin Glucagon-like peptide-1 Biodistribution Biological barriers Targeted delivery

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真核mRNA3′非翻译区的肿瘤抑制功能和表达调控

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生物化学与生物物理进展 2000年第5期27卷 472-476页

作者：刘定干中国科学院上海生物化学研究所上海200031

最近几年来 ,关于真核mRNA 3′UTR在肿瘤细胞恶性表型抑制中作用的研究 ,取得了非常令人鼓舞的进展 .目前已经发现 ,3′UTR参与一些已知的癌基因和抗癌基因的功能调控 ;一些抗癌基因的失活来源于其 3′ UTR的结构变化 ;而且又发现了一... 详细信息

最近几年来 ,关于真核mRNA 3′UTR在肿瘤细胞恶性表型抑制中作用的研究 ,取得了非常令人鼓舞的进展 .目前已经发现 ,3′UTR参与一些已知的癌基因和抗癌基因的功能调控 ;一些抗癌基因的失活来源于其 3′ UTR的结构变化 ;而且又发现了一些基因的 3′UTR在转染恶性细胞后表现抗癌基因活性 .此外 ,3′UTR在mRNA表达调控中的作用也已研究得更加深入 .现将最近几年来在这一领域的一部分研究进展情况。

关键词：肿瘤抑制表达调控 mRNA 3'UTR 细胞增殖

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