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External stimulation-controlled dynamic DNA devices for biosensing and biomedical applications

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Science China Chemistry 2023年第11期66卷 3105-3115页

作者： Wei Xu Feifei hu Jiajing li Jinhua Shang Xiaoqing liu Yan zeng Qiong Wu Fuan Wang Department of Gastroenterology Zhongnan Hospital of Wuhan UniversityCollege of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China School of Medicine Wuhan University of Science and TechnologyWuhan 430081China College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082China

DNA devices that can recognize molecular inputs and transform them into functional outputs in an autonomous manner have been actively pursued as versatile toolkits for controlled nanofabrication,molecular network regulation,biosensing and cellular function *** introduction of external stimuli-responsive units not only ensures the programmability and functionality of DNA devices themselves,but also confers rapid,remote and reversible dynamic regulation *** facilitates on-demand activation and expands the application scope of dynamic DNA ***,an overview of recent advances in the construction of stimuli-responsive DNA devices that respond to different exogenous triggers,including physical stimuli(e.g.,light,thermal,magnetic field,and electric field),chemical stimuli(e.g.,supermolecules,pH,redox,and metal ions),and biological cues(e.g.,protein,biomolecule,and nucleic acid),and their controllable nanofabrication and biomedical application have been *** current challenges and potential solutions of these externally responsive DNA devices for their future advancements in this emerging field are also discussed.

关键词： DNA device stimuli-responsiveness on-demand regulation DNAzyme biosensing

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Microstructural evolution of Mg-Al-Re alloy reinforced with alumina fibers

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Journal of Magnesium and Alloys 2020年第3期8卷 565-577页

作者： li li Dejiang li Xiaoqin zeng Alan A.Luo Bin hu Anil K.Sachdev liangliang Gu Wenjiang Ding Shanghai Jiao Tong University ShanghaiChina The Ohio State University ColumbusOHUnited States General Motors China Science Lab ShanghaiChina General Motors Global R&D Center WarrenMIUnited States

Few studies were reported on the phases'relationships of AE44(Mg-4.0Al-4.1RE-0.3Mn,wt.%)and its *** this work,AE44 alloy and Saffil(6-Al2O3)/AE44 Metal matrix composite(MMC)were both prepared by slow shot high pressure die casting(SS-HPDC)technology and their phase constitutions were all studied in detail using experimental techniques combined with CALPHAD(Calculation of Phase Diagram)*** results revealed that the alloy consists of the a-Mg matrix,A1hRE3 intermetallic phase,and one trace phase AI3RE,while the composite contains five major phases:a-Mg,5-AI2O3,AI3RE,MgO and *** two trace phases of A12RE and AI11RE3,respectively.A1hRE3 is partly derived from ALRE,while A13RE is a product of the peritectoid reaction between the two *** presence of MgO and Mg2Si is due to the interfacial reaction between the SiO2 binder in the fiber preforms and the molten magnesium during *** use of SiO2 binder in the preform manufacturing was limited/minimized to reduce the MgO formation in the MMC casting process,which can be detrimental to the fatigue performance of the MMC materials.

关键词： Mg-Al-RE Magnesium composite Slow shot high pressure die casting Microstructure CALPHAD AlxREy

Error Inhomogeneity in the Computation of Spherical Mean Displacement

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Journal of Meteorological Research 2017年第6期31卷 1133-1148页

作者： Xuezhong WANG Banghui hu Hong huANG Ju WANG Gang zeng Yanke TAN li ZOU Institute of Meteorology and Oceanography National University of Defense Technology School of Atmospheric Science and Key Laboratory of Mesoscale Severe Weather of Ministry of Education Nanjing University Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science &Technology

The traditional method for computing the mean displacement in latitude-longitude coordinates is a spherical meridional-zonal resultant displacement method （MRDM）, which regards the displacement as the resultant vector of the meridional and zonal displacement components. However, there are inhomogeneity and singularity in the computation error of the MRDM, especially at high latitudes. Using the NCEP/NCAR long-term monthly mean wind and idealized wind fields, the inhomogeneity in the MRDM was accessed by using a great circle displacement computing method （GCDM） for non-iterative cases. The MRDM and GCDM were also compared for iteration cases by taking the trajectories from a three-time level reference method as the real trajectories. In the horizontal direction, the GCDM assumes that an air particle moves along its locating great circle and that the magnitude of the displacement equals the arc length of the great circle. The inhomogeneity of the MRDM is evaluated in terms of the horizontal dis- tance error from the products of wind speed, lapse time, and angle difference from the GCDM displacement orient. The non-iterative results show that the mean horizontal displacement computed through the MRDM has both compu- tational and analytical errors. The displacement error of the MRDM depends on the wind speed, wind direction, and the departure latitude of the air particle. It increases with the wind speed and the departure latitude. The displacement magnitude error has a four-wave pattern and the displacement direction error has a two-wave feature in the definition range of the wind direction. The iterative result shows that the displacement magnitude error and angle error of the MRDM and GCDM with respect to the reference method increase with the lapse time and have similar distribution patterns. The mean magnitude error and the angle error of the MRDM are nearly twice as large as those of the GCDM.

关键词： mean displacement spherical coordinates error inhomogeneity polar singularity

Long-and Short-Term Self-Learning Models of Rolling Force in Rolling Process Without Gaugemeter of Plate

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Journal of Iron and Steel Research International 2009年第1期16卷 27-31,61页

作者： Zhu Fu-wen zeng Qing-liang hu Xian-lei li Xi-an liU Xiang-hua The State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang 110004Liaoning China The Second Plant of Plate Anyang Steel Co Ltd Anyang 455004 Henan China

Owing to a lack of gaugemeter and the variety of steel grades and standards in some plate mills, the longand short-term self-learning models of rolling force based on gauge soft-measuring with high precision were brought up. The soft-measuring method and target value locked method were used in these models to confirm the actual exit gauge of passes, and thick layer division and exponential smoothing method were used to dispose the deformation resistance parameter, which could be calculated from the actual data of the rolling process. The correlative mathematical methods can also be adapted to self-learning with gaugemeter. The models were applied to the process control system of AGC （automatic gauge control） reconstruction on 2800 mm finishing mill of Anyang steel and favorable effect was obtained.

关键词： plate self-learning soft measuring rolling force

Optimized Design for a Combined Die with Two Stress Rings in Cold Forging Considering Thermal-Mechanical Effects

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Journal of Shanghai Jiaotong university(Science) 2020年第3期25卷 304-314页

作者： li Zibo zeng Fan ZHAO Zhen hu Chengliang Institute of Forming Technology&Equipment Shanghai Jiao Tong UniversityShanghai 200030China

Stress analysis and optimization of combined die structure with two stress rings were *** thermoelastic deformation,the contact pressure at the interfaces between layers was ***,theoretical expressions of stress distribution for the combined die were *** thermal-mechanical effect under working conditions was *** verify the theoretical expressions,simulation work was *** of die design was carried out by defining radius ratio and shrink fit coefficient as optimization *** objective was to minimize the effective circumferential stress at the inner surface of the die insert,under the constraint that the maximum equivalent stress values of die insert and stress rings did not exceed their respective yield *** Kriging model was used to describe the influence of shrink fit and die dimensions on the objective function and the maximum equivalent *** a genetic algorithm,optimum parameters were found with a minimum circumferential stress of 442.9 MPa under a working stress of 1800 *** analysis of five selected optimal results was carried out,and the specific design parameters of these combined dies are different under the same level of circumferential stress,and the combined die is overdesigned if the thermal effect is ignored.

关键词： cold forging combined die die dimension optimization thermal-mechanical effect genetic algorithm

On the Differential Uniformity and Nonlinearity of a Class of Permutation Quadrinomials Over F_(2 2 m)

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Communications in Mathematical Research 2022年第2期38卷 223-245页

作者： Mengyu hu Nian li Xiangyong zeng hubei Key Laboratory of Applied Mathematics Faculty of Mathematics and StatisticsHubei UniversityWuhanChina

Permutation polynomials with low differential uniformity and high nonlinearity are preferred in cryptographic systems. In 2018, Tu, zeng and Helleseth constructed a new class of permutation quadrinomials over the finite field F_(2 2m) for an odd integer m. In this paper, we aim to investigate the differential uniformity and nonlinearity of this class of permutation polynomials so as to find 4-uniform permutation polynomials with high nonlinearity.

关键词： Differential uniformity finite field nonlinearity permutation polynomial

Stress Corrosion Cracking of High-strength Drill Pipe in Sour Gas Well

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Journal of Wuhan University of Technology(Materials Science) 2014年第4期29卷 813-816页

作者：张智 li Jing zeng Dezhi hu Junying HOU Duo ZHANG liehui SHI Taihe State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University

In high sour gas reservoir drilling process, it happens occasionally that high-strength drill pipe suffers brittle fracture failure due to stress corrosion cracking, and poses serious hazard to drilling safety. To solve this problem, this paper studied the stress corrosion cracking mechanism and infl uencing factors of highstrength drill pipe in sour environment with hydrogen permeation experiments and tensile tests. We simulated practical conditions in laboratory and evaluated the stress corrosion cracking performance of the high-strength drill pipe under conditions of high stress level. For the problems occurring in use of high-strength drill pipe on site, the paper proposed a technical measure for slower stress corrosion cracking.

关键词： sour environment high-strength drill pipe stress corrosion cracking

Precise Dating and Geological Significance of the Caledonian Shangyou Pluton in South Jiangxi Province

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Acta Geologica Sinica(English Edition) 2008年第2期82卷 399-408页

作者： MAO Jianren zeng Qingtao li Zilong hu Qing ZHAO Xilin YE Haimin Nanjing Institute of Geology and Mineral Resources Jiangsu Province Nanjing Jiangsu 210016 Earth Science College Jilin University Changchun Jilin 130061 Geoscience Department Zhejiang University Hangzhou Zhejiang 310027

The zircon SHRIMP dating age for the Shangyou granites is 464±11 Ma. The geological feature of the pluton is consistent with the isotopic age, which shows that it is a product of Caledonian orogenesis. The Shangyou granites are regarded as peraluminous crust-derived granites to possess the typical geochemical characteristics of calc-alkaline rocks on the active continental margin with enriched Si, K, Al （A/CNK -- 1.11 on average）, HREE, Rb, U, Th and heavily depleted V, Cr, Co, Ni, as well as Ti-Y, Nb-Ta, Zr, Sr, P and Ba, to be commonly corundum normative （av C -- 1.44）. The Shangyou granites with higher 87Sr/86Sr ratios （0.707126-0.712186）, ENd（t） values （-7.29 to -10.22） and （tDM） values （1.52-1.63 Ga）, which are considered to result from partial melting of continental crust metamorphic sedimentary rocks with relatively low of crust maturation degree corresponding to the Middle Proterozoic, to have some possible contributions of mantle-derived components. The Shangyou granites are regarded as post-collision granites, which were formed in a transitional tectonic setting from compression to extension in the Middle Ordovician period after the Yangtze plate was subducted beneath the Cathaysian plate. The Ar-Ar total ages of K-feldspar and biotite are 292.1 Ma and 295.5 Ma respectively, which have recorded information of a late-stage thermal alteration event.

关键词： granite precise dating geological significance Caledonian South Jiangxi Province

The metabolism and hepatotoxicity of ginkgolic acid(17:1) in vitro

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Chinese Journal of Natural Medicines 2018年第11期16卷 829-837页

作者： YAO Qing-Qing li li XU Ming-Cheng hu Hai-Hong ZHOU hui YU Lu-Shan zeng Su Institute of Drug Metabolism and Pharmaceutical Analysis Zhejiang Province Key Laboratory of Anti-Cancer Drug Research College of Pharmaceutical Sciences Department of Pharmacy & Geriatrics Institute of Zhejiang Province Zhejiang Hospital

Pharmacological activities and adverse side effects of ginkgolic acids(GAs), major components in extracts from the leaves and seed coats of Ginkgo biloba L, have been intensively studied. However, there are few reports on their hepatotoxicity. In the present study, the metabolism and hepatotoxicity of GA(17:1), one of the most abundant components of GAs, were investigated. Kinetic analysis indicated that human and rat liver microsomes shared similar metabolic characteristics of GA(17:1) in phase I and II metabolisms. The drug-metabolizing enzymes involved in GA(17:1) metabolism were human CYP1 A2, CYP3 A4, UGT1 A6, UGT1 A9, and UGT2 B15, which were confirmed with an inhibition study of human liver microsomes and recombinant enzymes. The MTT assays indicated that the cytotoxicity of GA(17:1) in HepG2 cells occurred in a time-and dose-dependent manner. Further investigation showed that GA(17:1) had less cytotoxicity in primary rat hepatocytes than in HepG2 cells and that the toxicity was enhanced through CYP1 A-and CYP3 A-mediated metabolism.

关键词： Ginkgolic acid (17 : 1) Cytotoxicity liver microsomes Recombinant enzyme Hepatotoxicity