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Sedimentary diatom and pigment-inferred recent anthropogenic accelerated eutrophication of a Mediterranean lake(Lake Dojran,Republic of North Macedonia/Greece)

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Journal of Oceanology and Limnology 2020年第6期38卷 1787-1798页

作者： ZHANG Xiaosen xu xinyu Jane MREED Institute of Loess Plateau Shanxi UniversityTaiyuan 030006China Department of Geography Geology and EnvironmentUniversity of HullHull HU67RXUK

Lake eutrophication is recognised as a serious global challenge,and many regional legislative programmes are being made to attempt to relieve nutrient pollution and restore deteriorated lake ecological ***,it is of primary importance to understand the degradation processes and reference *** palaeolimnological approach allows us to use ecological evidences preserved in lake sediments to track the changes of lake trophic status under human ***,a proxy for ecological and limnological change,and pigments,a proxy for algal production and composition,were analysed on a short sediment sequence from Lake Dojran(Republic of North Macedonia and Greece),and their preservation qualities were evaluated before environmental *** diatom preservation is inferred mainly from the consistent co-occurrence of robust,highly-silicified taxa and small taxa throughout the *** evaluation of the comparison between wet sediment samples in dark and cold storage and their corresponding dry sediment samples lyophilized immediately after the recovery reveals that sediment restoration conditions are critical for the accuracy of *** show that the increased chlorophyll and xanthophyll pigment concentrations,particularly the siliceous-algae pigment fucoxanthin and diatoxanthin,together with the distinct increase in diatom concentration,indicate accelerated lake eutrophication and a major ecological shift linked to intensified water abstraction practice and agricultural expansion in the late 18th to early 19th *** of diatom assemblage composition is muted probably by the dominance of widely-tolerant small fragilaroid species in diatom composition and the better competitive ability of cyanobacteria and chlorophytes than diatoms for low light under eutrophic and turbid *** study improves our understanding of recent human-induced environmental change and current ecological restoration target in this lake.

关键词： diatom,pigment Lake Dojran Mediterranean lake eutrophication palaeolimnology

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Morphology control and photocatalytic characterization of WO_3 nanofiber bundles

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Chinese Chemical Letters 2018年第9期29卷 1350-1354页

作者： Ying Zhang Defeng Zhang xinyu xu Bingsen Zhang College of Chemistry Chemical Engineering and Environmental Engineering Liaoning Shihua University Shenyang National Laboratory for Materials Science Institute of Metal research Chinese Academy of Sciences

The design and fabrication of semiconductor photocatalysts have attracted much attention. Herein, the effect of pH value and soluble salt additives on crystal structure, morphology and photocatalytic properties of WO3 was investigated in detail. It was found that the phase structure of WO3 changed from monoclinic to hexagonal phase when pH value of the solution increased. The ultraviolet-visible absorption spectra show that the monoclinic and hexagonal WO3 had absorbance from 600 nm to the ultraviolet-visible region. Hexagonal WO3 with nanofiber bundle morphology was successfully synthesized through Na2SO4 and Zn（CH3COO）2.2H2O-assisted hydrothermal method when pH value was 0.8. It exhibits the highest photocatalytic efficiency and better than that of cubic-shaped rnonoclinic WO3. The shuttle-like hexagonal WO3 prepared at pH 1.4 gives much lower activity. The morphology is a decisive parameter for the photocatalytic properties of WO3.

关键词： Tungstic trioxide Microstructure Nanofiber bundles Hydrothermal method Photocatalytic activity

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Hawk‐eye‐inspired perception algorithm of stereo vision for obtaining orchard 3D point cloud navigation map

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CAAI Transactions on Intelligence Technology 2023年第3期8卷 987-1001页

作者： Zichao Zhang Jian Chen xinyu xu Cunjia Liu Yu Han College of Engineering China Agricultural UniversityBeijingChina Jiangsu Province and Education Ministry Co‐sponsored Synergistic Innovation Center of Modern Agricultural Equipment Jiangsu UniversityZhenjiangChina Key Laboratory of Spatial‐temporal Big Data Analysis and Application of Natural Resources in Megacities MNRShanghaiChina Department of Aeronautical and Automotive Engineering Loughborough UniversityLoughboroughLeicestershireUK College of Water Resources and Civil Engineering China Agricultural UniversityBeijingChina State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhenChina

The binocular stereo vision is the lowest cost sensor for obtaining 3D *** the weakness of long‐distance measurement and stability,the improvement of accuracy and stability of stereo vision is urgently required for application of precision *** address the challenges of stereo vision long‐distance measurement and stable perception without hardware upgrade,inspired by hawk eyes,higher resolution perception and the adaptive HDR(High Dynamic Range)were introduced in this *** the function from physiological structure of‘deep fovea’and‘shallow fovea’of hawk eye,the higher resolution reconstruction method in this paper was aimed at ac-curacy *** by adjustment of pupils,the adaptive HDR method was proposed for high dynamic range optimisation and stable *** various light conditions,compared with default stereo vision,the accuracy of proposed algorithm was improved by 28.0%evaluated by error ratio,and the stability was improved by 26.56%by disparity *** fixed distance measurement,the maximum improvement was 78.6%by standard *** on the hawk‐eye‐inspired perception algorithm,the point cloud of orchard was improved both in quality and *** hawk‐eye‐inspired perception algorithm contributed great advance in binocular 3D point cloud recon-struction in orchard navigation map.

关键词： adaptive high dynamic range binocular stereo vision hawk‐eye‐inspired perception point cloud of orchard super‐resolution generative adversarial network

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Simulation of earth gravity field using satellite constellation with variable inclination configuration

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Geodesy and Geodynamics 2021年第5期12卷 323-328页

作者： Qian Zhao Weiping Jiang xinyu xu Xiancai Zou Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake AdministrationBeijing 100036China Research Center of GNSS Wuhan University129 Luoyu RoadWuhan 430079China School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan 430079China

Based on a satellite constellation composed of two GRACE-type satellite formations with different inclinations(near polar orbit + low inclination) and the theory of repeat orbit cycle, we discuss the methods for selecting medium-low inclinations for global and local gravity fields. The effects of this constellation configuration on gravity field inversion are comparatively analyzed using a whole-course dynamics simulation. The results show that compared with the single GRACE-type satellite formation,the use of satellite constellations with different inclination configurations improves the gravity solution precision by 34%. The inclusion of multi-directional observations can improve the spatio-temporal resolution of the satellite missions, and yield gravity field solutions with higher isotropic ***, it is necessary to select the optimal low inclination according to the study area, which will have a significant influence on the gravity field solution.

关键词： Satellite constellation Low inclination Multi-directional observations Inversion of gravity field

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Fe_(3)O_(4)@SiO_(2)-Protein A-oHSV/CD63 Ab for Capturing Virus and Exosomes

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Journal of Analysis and Testing 2024年第3期8卷 335-350页

作者： Wenqing Zheng Pingyi Zheng Ran Zhao xinyu xu Xiao Zhang Xiaoqian Yuan Ying xu Zichuan Liu Youxin Li Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency Collaborative Innovation Center of Chemical Science and EngineeringSchool of Pharmaceutical Science and TechnologyFaculty of MedicineTianjin UniversityTianjin300072China

Protein A modified magnetic spheres(Fe_(3)O_(4)@SiO_(2)-Protein A)with 22.7 emu/g saturation magnetization were prepared and *** spheres had a diameter of 10 nm and was stable up to 229.2℃,and can bond 19.694 mg/g of Protein *** Fe_(3)O_(4)@SiO_(2)-Protein A was firstly combined with oHSV-BJ-2-A antibody to capture oHSV from disease venom,and the amount of binding virus was 1.92×10^(7)to 3.44×10^(7)PFU/***_(3)O_(4)@SiO_(2)-Protein A was modified with CD63 antibody,which was further fixed using dissuccinimide octylate(DSS)as a crosslinking *** prepared Fe_(3)O_(4)@SiO_(2)-Protein A-CD63 Ab was useful in isolating and enriching exosomes from cell *** with commercial kits,Fe_(3)O_(4)@SiO_(2)-Protein A-CD63 Ab demonstrated a better purification effect,which was successfully monitored using capillary *** total content of exosomes protein extracted using Fe_(3)O_(4)@SiO_(2)-Protein A-CD63 was 3.4 mg/g,which was obviously higher than that reported in some *** addition,Fe_(3)O_(4)@SiO_(2)-Protein A-CD63 Ab also showed its repeatability through bonding and elution of 5 cycles,which was effective in cost *** indicated Fe_(3)O_(4)@SiO_(2)-Protein A-CD63 Ab had the potential for large-scale purification of exosomes in practical applications.

关键词： Immunomagnetic spheres Antibody Exosome Herpes simplex virus

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Analysis of the impact on the gravity field determination from the data with the ununiform noise distribution using block-diagonal least squares method

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Geodesy and Geodynamics 2016年第3期7卷 194-201页

作者： Wei Liang Jiancheng Li xinyu xu Yongqi Zhao School of Geodesy and Geomatics Wuhan University State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University

The block-diagonal least squares method, which theoretically has specific requirements for the observation data and the spatial distribution of its precision, plays an important role in ultra-high degree gravity field determination. On the basis of block-diagonal least squares method, three data processing strategies are employed to determine the gravity field models using three kinds of simulated global grid data with different noise spatial distri- bution in this paper. The numerical results show that when we employed the weight matrix corresponding to the noise of the observation data, the model computed by the least squares using the full normal matrix has much higher precision than the one estimated only using the block part of the normal matrix. The model computed by the block-diagonal least squares method without the weight matrix has slightly lower precision than the model computed using the rigorous least squares with the weight matrix. The result offers valuable reference to the using of block-diagonal least squares method in ultra-high gravity model determination.

关键词： Block-diagonal least squaresmethod Precision distribution Parameter sequence Gravity anomaly Gravity field

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A GOCE only gravity model GOSG01S and the validation of GOCE related satellite gravity models

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Geodesy and Geodynamics 2017年第4期8卷 260-272页

作者： xinyu xu Yongqi Zhao Tilo Reubelt Robert Tenzer School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China Key Laboratory of Geospace Environment and Geodesy Ministry of Education 129 Luoyu Road Wuhan 430079 China Institute of Geodesy University of Stuttgart Geschwister-Scholl-Str. 24D 70174 Stuttgart Germany

We compile the GOCE-only satellite model GOSG01S complete to spherical harmonic degree of 220 using Satellite Gravity Gradiometry （SGG） data and the Satellite-to-Satellite Tracking （SST） observations along the GOCE orbit based on applying a least-squares analysis. The diagonal components （Vxx, Vyy, Vzz） of the gravitational gradient tensor are used to form the system of observation equations with the band-pass ARMA filter. The point-wise acceleration observations （ax, ay, az） along the orbit are used to form the system of observation equations up to the maximum spherical harmonic degree/order 130. The analysis of spectral accuracy characteristics of the newly derived gravitational model GOSG01S and the existing models GOTIM04S, GODIR04S, GOSPW04S and JYY_GOCE02S based on their comparison with the ultrahigh degree model EIGEN-6C2 reveals a significant consistency at the spectral window approximately between 80 and 190 due to the same period SGG data used to compile these models. The GOCE related satellite gravity models GOSG01S, GOTIM05S, GODIR05S, GOTIM04S, GODIR04S, GOSPW04S, JYY_- GOCE02S, EIGEN-6C2 and EGM2008 are also validated by using GPS-leveling data in China and USA. According to the truncation at degree 200, the statistic results show that all GGMs have very similar differences at GPS-leveling points in USA, and all GOCE related gravity models have better performance than EGM2008 in China. This suggests that all these models provide much more information on the gravity field than EGM2008 in areas with low terrestrial gravity coverage. And STDs of height anomaly differences in China for the selected truncation degrees show that GOCE has improved the accuracy of the global models beyond degree 90 and the accuracies of the models improve from 24 cm to 16 cm. STDs of geoid height differences in USA show that GOSG01S model has best consistency comparing with GPSleveling data for the frequency band of the degree between 20 and 160.

关键词： Earth's gravity field Geopotential model Gravity gradient Validation SateLlite-to-satellite tracking

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High-contrast imaging based on wavefront shaping to improve low signal-to-noise ratio photoacoustic signals using superpixel method

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Chinese Physics B 2020年第3期29卷 251-258页

作者： Xinjing Lv xinyu xu Qi Feng Bin Zhang Yingchun Ding Qiang Liu College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084China

Photoacoustic(PA) imaging has drawn tremendous research interest for various applications in biomedicine and experienced exponential growth over the past decade. Since the scattering effect of biological tissue on ultrasound is two-to three-orders magnitude weaker than that of light, photoacoustic imaging can effectively improve the imaging ***, as the depth of imaging further increases, the incident light is seriously affected by scattering that the generated photoacoustic signal is very weak and the signal-to-noise ratio(SNR) is quite low. Low SNR signals can reduce imaging quality and even cause imaging failure. In this paper, we proposed a new wavefront shaping and imaging method of low SNR photoacoustic signal using digital micromirror device(DMD) based superpixel method. We combined the superpixel method with DMD to modulate the phase and amplitude of the incident light, and the genetic algorithm(GA) was used as the wavefront shaping algorithm. The enhancement of the photoacoustic signal reached 10.46. Then we performed scanning imaging by moving the absorber with the translation stage. A clear image with contrast of 8.57 was obtained while imaging with original photoacoustic signals could not be achieved. The proposed method opens new perspectives for imaging with weak photoacoustic signals.

关键词： photoacoustic imaging wavefront shaping superpixel method high contrast imaging

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Feasibility study on application of satellite formations for eliminating the influence from aliasing error of ocean tide model

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Science China Earth Sciences 2015年第2期58卷 474-481页

作者： ZHAO Qian JIANG WeiPing xu xinyu ZOU XianCai Institute of Earthquake Science China Earthquake Administration GNSS Research Center Wuhan University School of Geodesy and Geomatics Wuhan University

Currently,aliasing error of temporal signal model becomes the main factor constraining the accuracy of temporal gravity *** provision of three types of satellite formations,i.e.,GRACE-type,Pendulum-type and n-s-Cartwheel-type,which are suitable for gravity mission and composed of observation in different directions,here we design two cases and conduct a simulation experiment on the feasibility to apply satellite formations for eliminating the influence from the aliasing error of ocean tide *** result of our experiment shows that,when the aliasing error is disregarded,n-s-Cartwheel formation can provide the best conditions for gravity field determination,which,compared with GRACE-type,can improve the accuracy by 43%.When aliasing error of the ocean tide model acts as the main source of error,the satellite formation applied in dynamic method for gravity field inversion cannot eliminate aliasing or improve the accuracy of gravity *** due to its higher sensitivity to the high-degree variation of gravity field,the Cartwheel-type formation,which includes the radial observation,can result in the gravity field containing more high-frequency signals for the ocean tide model error,and lead to a dramatically larger error.

关键词： satellite formation aliasing error ocean tide model gravity field inversion

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Zinc Ion-Induced Immune Responses in Antitumor Immunotherapy

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CCS Chemistry 2024年第9期6卷 2210-2229页

作者： Ying Yang Huanhuan Fan xinyu xu Shankun Yao Wenhao Yu Zijian Guo State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringChemistry and Biomedicine Innovation Center(ChemBIC)Nanjing UniversityNanjing 210023

Zinc has emerged as a crucial metal in the field of antitumor *** its recognized significance,the specific molecular mechanisms behind zinc ion-mediated antitumor immune responses remain inadequately ***,we present a comprehensive analysis of the effects of zinc ions on immune regulation in antitumor *** ions overload within tumor cells results in the generation of reactive oxygen species(ROS)through two mechanisms:the leakage of electrons from aerobic respiration in mitochondria and the oxidation of reduced nicotinamide adenine dinucleotide phosphate(NADPH)by NADPH oxidase 1(NOX1).The accumulation of ROS and the resulting damage to mitochondrial DNA(mtDNA)activate multiple signaling pathways,leading to the production of high levels of interferons and inflammatory ***,excessive zinc ions induce tumor cell pyroptosis through two pathways:the caspase-1/GSDMD-dependent canonical pathway and the caspase-3/GSDME-dependent alternative pathway,leading to the exposure of many damage-associated molecular patterns(DAMPs).As a result,strong systemic antitumor immunity is triggered,leading to the inhibition of tumor *** study unveils the intricate network of signaling pathways mediated by zinc ions in the tumor microenvironment(TME).Such findings not only lay a solid foundation for the development of zinc-based antitumor drugs but also advance the field of zinc-based metalloimmunotherapy.

关键词： zinc ion immune responses signal transduction pyroptosis antitumor immunotherapy

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