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Drug target discovery by magnetic nanoparticles coupled mass spectrometry

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Journal of Pharmaceutical Analysis 2021年第1期11卷 122-127页

作者： Dandan Xia Baoling Liu Xiaowei Xu Ya Ding Qiuling zheng Department of Pharmaceutical Analysis School of PharmacyChina Pharmaceutical UniversityNanjing210009China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing210009China Key Laboratory of Drug Metabolism and Pharmacokinetics China Pharmaceutical UniversityNanjing210009China

Drug target discovery is the basis of drug *** elucidates the cause of disease and the mechanism of drug action,which is the essential of drug *** discovery performed in biological systems is complicated as proteins are in low abundance and endogenous compounds may interfere with drug ***,methods to track drug-target interactions in biological matrices are urgently *** this work,a Fe_(3)O_(4) nanoparticle-based approach was developed for drug-target screening in biofluids.A known ligand-protein complex was selected as a principle-to-proof example to validate the *** incubation in cell lysates,ligand-modified Fe_(3)O_(4) nanoparticles bound to the target protein and formed complexes that were separated from the lysates by a magnet for further *** large surface-to-volume ratio of the nanoparticles provides more active sites for the modification of chemical *** enhances the opportunity for ligand-protein interactions,which is beneficial for capturing target proteins,especially for those with low ***,a one-step magnetic separation simplifies the pre-processing of ligand-protein complexes,so it effectively reduces the endogenous ***,the present nanoparticle-based approach has the potential to be used for drug target screening in biological systems.

关键词： Drug-target discovery Nanoparticle Mass spectrometry

A universal elliptical disc(UED)model to represent natural rock fractures

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International Journal of Mining Science and Technology 2022年第2期32卷 261-270页

作者： Jun zheng Jichao Guo Jiongchao Wang Honglei Sun Jianhui Deng Qing Lv Department of Civil Engineering Zhejiang UniversityHangzhou 310058China Center for Balance Architecture Zhejiang UniversityHangzhou 310007China College of Civil Engineering Zhejiang University of TechnologyHangzhou 310023China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource&HydropowerSichuan UniversityChengdu 610065China

Since natural fractures are often non-equidimensional,the circular disc model still has great *** contrast,the elliptical disc model is more applicable to representing natural fractures,especially for slender *** paper developed a universal elliptical disc(UED)model by incorporating the center point,size,and azimuth of fractures as ***,with respect to the azimuth of elliptical fractures in three-dimensional(3D)space,we proposed a paradigm to construct its probability density function(PDF)by coupling the orientation and rotation angle of long axis based on three coordinate *** illustrate the construction process of the PDF of the fracture azimuth,we took the orientation following the Fisher distribution and the rotation angle following Von Mises distribution as an example.A rock slope is used to show the use of the developed UED model,and the 3D DFNs for the slope rock mass are generated by Monte Carlo *** addition,the DFNs for the rock mass are also generated based on the existing circular disc model and non-universal elliptical disc *** comparison results from the three models clearly illustrate the superiority of the UED model over the existing circular and non-universal elliptical disc models.

关键词： Discrete fracture networks Rock mass Discontinuity Elliptical disc model Fisher distribution Monte Carlo simulation

High-temperature strength-coercivity balance in a FeCo-based soft magnetic alloy via magnetic nanoprecipitates

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Journal of Materials Science & Technology 2021年第22期81卷 36-42页

作者： Kaisheng Ming Shuimiao Jiang Xiaoyuan Niu Bo Li Xiaofang Bi Shijian zheng State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin300130China Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology School of Materials Science and EngineeringHebei University of TechnologyTianjin300130China Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang UniversityBeijing100191China School of Chemical Engineering and Technology Hebei University of TechnologyTianjin300130China

Precipitation strengthening is an effective approach to enhance the strength of soft magnetic alloys for applications at high temperatures,while inevitably results in deterioration in coercivity due to the pinning effect on the domain wall ***,we realize a good combination of high-temperature strength and ductility(ultimate tensile strength of 564 MPa and elongation of~20%,respectively)as well as low coercivity(6.97 Oe)of FeCo-2V-0.3Cr-0.2Mo soft magnetic alloy through introducing high-density magnetic *** magnetic nanoprecipitates are characterized by FeCo-based phase with disordered body-centered cubic structure,which enables the alloy to have a low *** addition,these nanoprecipitates can impede the dislocation motion and suppress the brittle fracture,which lead to a high tensile strength and *** work provides a guideline to enhance strength and ductility while maintaining low coercivity in soft magnetic alloys via magnetic nanoprecipitates.

关键词： FeCo-based soft magnetic alloys Strength Ductility Coercivity Magnetic nanoprecipitates

Visual Superordinate Abstraction for Robust Concept Learning

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Machine Intelligence Research 2023年第1期20卷 79-91页

作者： Qi zheng Chao-Yue Wang Dadong Wang Da-Cheng Tao University of Sydney Sydney 2008Australia JD Explore Academy Beijing 100176China DATA61 Commonwealth Scientific and Industrial Research OrganisationSydney 2122Australia

Concept learning constructs visual representations that are connected to linguistic semantics, which is fundamental to vision-language tasks. Although promising progress has been made, existing concept learners are still vulnerable to attribute perturbations and out-of-distribution compositions during inference. We ascribe the bottleneck to a failure to explore the intrinsic semantic hierarchy of visual concepts, e.g., {red, blue,···} ∈“color” subspace yet cube ∈“shape”. In this paper, we propose a visual superordinate abstraction framework for explicitly modeling semantic-aware visual subspaces(i.e., visual superordinates). With only natural visual question answering data, our model first acquires the semantic hierarchy from a linguistic view and then explores mutually exclusive visual superordinates under the guidance of linguistic hierarchy. In addition, a quasi-center visual concept clustering and superordinate shortcut learning schemes are proposed to enhance the discrimination and independence of concepts within each visual superordinate. Experiments demonstrate the superiority of the proposed framework under diverse settings, which increases the overall answering accuracy relatively by 7.5% for reasoning with perturbations and 15.6% for compositional generalization tests.

关键词： Concept learning visual question answering weakly-supervised learning multi-modal learning curriculum learning

Sensitivity analysis of Biome-BGCMuSo for gross and net primary productivity of typical forests in China

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Forest Ecosystems 2022年第1期9卷 111-123页

作者： Hongge Ren Li Zhang Min Yan Xin Tian Xingbo zheng Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing100094China University of Chinese Academy of Sciences Beijing100049China Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing100091China Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang110016China Research Station of Changbai Mountain Forest Ecosystems Chinese Academy of SciencesAntu133613JilinChina

Background:Process-based models are widely used to simulate forest productivity,but complex parameterization and calibration challenge the application and development of these *** analysis of numerous parameters is an essential step in model calibration and carbon flux ***,parameters are not dependent on each other,and the results of sensitivity analysis usually vary due to different forest types and ***,global and representative sensitivity analysis would provide reliable information for simple ***:To determine the contributions of input parameters to gross primary productivity(GPP)and net primary productivity(NPP),regression analysis and extended Fourier amplitude sensitivity testing(EFAST)were conducted for Biome-BGCMuSo to calculate the sensitivity index of the parameters at four observation sites under climate gradient from ***:Generally,GPP and NPP were highly sensitive to C:Nleaf(C:N of leaves),Wint(canopy water interception coefficient),k(canopy light extinction coefficient),FLNR(fraction of leaf N in Rubisco),MRpern(coefficient of linear relationship between tissue N and maintenance respiration),VPDf(vapor pressure deficit complete conductance reduction),and SLA1(canopy average specific leaf area in phenological phase 1)at all observation *** sensitive parameters occurred at four observation sites within different climate *** and NPP were particularly sensitive to FLNR,SLA1 and Wint,and C:Nleaf in temperate,alpine and subtropical zones,***:The results indicated that sensitivity parameters of China's forest ecosystems change with climate *** found that parameter calibration should be performed according to plant functional type(PFT),and more attention needs to be paid to the differences in climate and *** findings contribute to determining the target parameters in field experiments and model calibration.

关键词： Sensitivity analysis Biome-BGCMuSo Productivity Regression analysis EFAST

A Comparison Study of Synkinematic Illite Isolation,Quantitative X-ray Powder Diffraction,and K-Ar Dating for Direct Fault Gouge Analyses

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Acta Geologica Sinica(English Edition) 2023年第2期97卷 636-650页

作者： zheng Yong LI Haibing LI Junjie ZHANG Guohe SI Jialiang Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Jiangsu Donghai Continental Deep Hole Crustal Activity National Observation and Research Station DonghaiJiangsu 222300China Beijing Research Institute of Uranium Geology Beijing 100029China Military and Civilian Integration Geological Survey Center Chengdu 610000China

K-Ar dating of synkinematic illite is increasingly recognized as a central method to constrain the timing of shallow crustal *** of efficient sample preparation and quantitative identification of illite polytypes are critical to acquiring K-Ar isotope data for authigenic *** this respect,we compared the commonly used clay size separation method through centrifugation with vacuum filtration technology,showing that the former is prone to extract fractions with finer particle sizes under similar conditions,thus improving the error in the authigenic end-member ***,we demonstrated that the side-packed mounting method for X-ray diffraction analysis can significantly enhance the randomness in powder samples,thus improving the quantification accuracy compared with the front-packed and back-packed *** validity of our quantification method was confirmed by comparing Profex■modeling patterns with a suite of synthetic mixtures of known compositions,yielding an average analytical error of 3%.Dating results of these artificial mixtures and the reference materials indicated that a large range in percentages of detrital illite and a sufficient amount of age data will produce reliable results for ages of both extrapolated ***,if the range is limited,the extrapolated age close to those of datasets is still reliable.

关键词： illite polytypes fault gouge clay size separation mounting method Profex■ extrapolated K-Ar age

On Dynamic Channel Emulation in Sector MPAC for Over-the-Air Testing of Beamformed Massive MIMO Devices

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China Communications 2023年第4期20卷 41-56页

作者： Xiaochen Chen Heng Wang Weimin Wang zheng Liu Yuanan Liu China Academy of Information and Communications Technology Beijing 100191China Beijing Key Laboratory of Work Safety Intelligent Monitoring Department of Electronic EngineeringBeijing University of Posts and TelecommunicationsBeijing 100876China

In this article,novel emulation strategies for the sectored multiple probe anechoic chamber(SMPAC)are proposed to enable the reliable evaluation of the massive multiple-input multiple-output(MIMO)device operating at beamforming mode,which requires a realistic non-stationary channel *** the dynamic propagation emulation,an efficient closed-form probe weighting strategy minimizing the power angular spectrum(PAS)emulation errors is derived,substantially reducing the associated computational *** the other hand,a novel probe selection algorithm is proposed to reproduce a more accurate fading *** standard channel models and setup configurations are comprehensively simulated to validate the capacity of the proposed *** simulation results show that more competent active probes are selected with the proposed method compared to the conventional ***,the derived closedform probe weighting strategy offers identical accuracy to that obtained with complicated numerical ***,a realistic dynamic channel measured in an indoor environment is reconstructed with the developed methodologies,and 95.6%PAS similarity can be achieved with 6 active *** satisfactory results demonstrate that the proposed algorithms are suitable for arbitrary channel emulation.

关键词： beamforming channel emulation massive MIMO device multiple probe anechoic chamber(MPAC) over-the-air testing

Identifying drivers of urban landuse changes in the Wenchuan earthquake- affected area by using night-time light data

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Journal of Mountain Science 2024年第4期21卷 1140-1159页

作者： HUANG Tao DING Mingtao GENG Dongxian GAO Zemin zheng Hao School of Civil Engineering and Architecture Southwest University of Science and TechnologyMianyang 621010China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Analysis and Test Center of Sichuan Province Chengdu 610023China

To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken ***,spatiotemporal evolution and its driving factors of urban land in earthquake-prone areas remains limited due to the scarcity of ground observation *** research,leveraging night-time light remote sensing imagery and land cover data,conducted a comprehensive analysis of the long-term evolution characteristics of urban land in earthquake-prone *** introduced methodologies for assessing the socio-economic impact and the primary natural environmental factors driving urban land evolution in these *** validate the proposed methods,the 2008 Wenchuan earthquake-affected area in China was selected as a representative study *** results indicated that the average Digital Number(DN)values in socio-economically impacted areas showed a trend of rising,falling,and then rising again after the *** values in three types of damaged areas including Type Ⅱ,Type Ⅲ,and Type Ⅳ exceeded pre-earthquake *** analysis of determinative factors influencing urban land evolution revealed that slope and elevation were key elements in controlling urban land expansion before the earthquake,whereas factors such as slope,elevation,lithology,and faults had a stronger influence on urban land expansion after the *** can be seen that,in view of the differences in the natural conditions of regions for post-disaster reconstruction,the local government need to actively adjust and adapt to urban spatial planning,so as to leverage the scale effect of large-scale inputs of funds,facilities,human resources and other factors after the disaster,thus enhancing resilience and recovery efficiency in response to disaster impacts.

关键词： Wenchuan earthquake Night-time lights Urban land Post-earthquake reconstruction

Research on wind erosion processes and controlling factors based on wind tunnel test and 3D laser scanning technology

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Journal of Arid Land 2022年第9期14卷 1009-1021页

作者： YAN Ping WANG Xiaoxu zheng Shucheng WANG Yong LI Xiaomei Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Zhuhai Branch of State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityZhuhai 519087China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China MOE Engineering Research Centre of Desertification and Blown-sand Control Beijing 100875China Institute of Geographical Sciences Henan Academy of SciencesZhengzhou 450052China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China

The study of wind erosion processes is of great importance to the prevention and control of soil wind *** this study,three structurally intact soil samples were collected from the steppe of Inner Mongolia Autonomous Region,China and placed in a wind tunnel where they were subjected to six different wind speeds(10,15,17,20,25,and 30 m/s)to simulate wind erosion in the wind *** each test,the soil surfaces were scanned by a 3D laser scanner to create a high-resolution Digital Elevation Model(DEM),and the changes in wind erosion mass and microtopography were *** on this,we performed further analysis of wind erosion-controlling *** study results showed that the average measurement error between the 3D laser scanning method and weighing method was 6.23%for the three undisturbed soil *** increasing wind speed,the microtopography on the undisturbed soil surface first became smooth,and then fine stripes and pits gradually *** the initial stage of wind erosion processes,the ability of the soil to resist wind erosion was mainly affected by the soil *** the late stage of wind erosion processes,the degree of soil erosion was mainly affected by soil organic matter and CaCO_(3)*** results of this study are expected to provide a theoretical basis for soil wind erosion control and promote the application of 3D laser scanners in wind erosion monitoring.

关键词： 3D laser scanning technology wind erosion wind tunnel test wind erosion depth microtopography soil hardness