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BANDED M-MATRIX SPLITTING PRECONDITIONER FOR RIESZ SPACE FRACTIONAL REACTION-DISPERSION EQUATION

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Journal of Computational Mathematics 2024年第2期42卷 372-389页

作者： shiping Tang Aili yang Yujiang Wu School of Mathematics and Statistics Lanzhou UniversityLanzhou 730000China School of Mathematics and Statistics Hainan Normal UniversityHaikou 570000China

Based on the Crank-Nicolson and the weighted and shifted Grunwald operators,we present an implicit difference scheme for the Riesz space fractional reaction-dispersion equations and also analyze the stability and the convergence of this implicit difference scheme.However,after estimating the condition number of the coefficient matrix of the discretized scheme,we find that this coefficient matrix is ill-conditioned when the spatial mesh-size is sufficiently small.To overcome this deficiency,we further develop an effective banded M-matrix splitting preconditioner for the coefficient matrix.Some properties of this preconditioner together with its preconditioning effect are discussed.Finally,Numerical examples are employed to test the robustness and the effectiveness of the proposed preconditioner.

关键词： Riesz space fractional equations Toeplitz matrix conjugate gradient method Incomplete Cholesky decomposition Banded M-matrix splitting

Enhancing the mechanical properties of casting eutectic high -entropy alloys via W addition

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1364-1372页

作者： Xu yang Dezhi Chen Li Feng Gang Qin shiping Wu Ruirun Chen National Key Laboratory for Precision Hot Processing of Metals School of Material Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

The effect of W element on the microstructure evolution and mechanical properties of Al_(1.25)CoCrFeNi3 eutectic high-entropy alloy and Al_(1.25)CoCrFeNi_(3-x)W_(x)(x=0,0.05,0.1,0.3,and 0.5;atomic ratio)high-entropy alloys(HEAs)were explored.Results show that the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs are composed of face-centered cubic and body-centered cubic(BCC)phases.As W content increases,the microstructure changes from eutectic to dendritic.The addition of W lowers the nucleation barrier of the BCC phase,decreases the valence electron concentration of the HEAs,and replaces Al in the BCC phase,thus facilitating the nucleation of the BCC phase.Tensile results show that the addition of W greatly improves the mechanical properties,and solid-solution,heterogeneous-interface,and second-phase strengthening are the main strengthening mechanisms.The yield strength,tensile strength,and elongation of the Al_(1.25)CoCrFeNi2.95W0.05 HEA are 601.44 MPa,1132.26 MPa,and 15.94%,respectively,realizing a balance between strength and plasti-city.The fracture mode of the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs is ductile–brittle mixed fracture,and the crack propagates and initiates in the BCC phase.The eutectic lamellar structure impedes crack propagation and maintains plasticity.

关键词： high-entropy alloy microstructure mechanical property fracture behavior

Nucleus-targeting orange-emissive carbon dots delivery adriamycin for enhanced anti-liver cancer therapy

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Chinese Chemical Letters 2024年第6期35卷 421-426页

作者： Qiang Li Jiangbo Fan Hongkai Mu Lin Chen Yongzhen yang shiping Yu The Second Hospital of Shanxi Medical University Taiyuan 030001China Shanxi Medical University Taiyuan 030001China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030032China

Carbon dots(CDs)with precise targeting function show great potential in the field of drug delivery therapeutics.In this study,the functionalized nucleus-targeting orange-emissive CDs with nuclear localization sequence(NLS)were loaded with adriamycin(DOX)to obtain a nucleus-targeting orange-emissive CDs drug delivery system(CDs-NLS-DOX),which delivered DOX to tumor cell nuclei to enhance its anti-tumor activity.The drug carrier orange-emissive CDs showed excitation-independent behavior,stable and enhanced imaging capability and good biocompatibility in vitro and in vivo.Meanwhile,the CDs-NLS could target the nuclei efficiently,and the CDs-NLS-DOX complexes had a high drug loading rate(59.4%)after loading DOX,exhibiting p H-dependent DOX release behavior through breaking acylhydrazone bond in a weak acidic environment.In addition,the CDs-NLS-DOX complexes exhibited an enhanced killing activity against human hepatoma cells(HepG2).The in vivo therapeutic effects on HepG2 nude mice transplanted tumors indicated the CDs-NLS-DOX had a stronger ability to inhibit tumor growth compared to free DOX.In short,CDs-NLS-DOX is expected to be a precise and efficient nucleus-targeting nano-drug delivery system for tumor treatment.

关键词： Carbon dots Nucleus-targeting Adriamycin Drug delivery system Liver cancer therapy

Numerical Investigation of the Angle of Attack Effect on Cloud Cavitation Flow around a Clark-Y Hydrofoil

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2947-2964页

作者： Di Peng Guoqing Chen Jiale Yan shiping Wang College of Engineering Peking UniversityBeijing100871China College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China

Cavitation is a prevalent phenomenon within the domain of ship and ocean engineering,predominantly occurring in the tail flow fields of high-speed rotating propellers and on the surfaces of high-speed underwater vehicles.The re-entrant jet and compression wave resulting from the collapse of cavity vapour are pivotal factors contributing to cavity instability.Concurrently,these phenomena significantly modulate the evolution of cavitation flow.In this paper,numerical investigations into cloud cavitation over a Clark-Y hydrofoil were conducted,utilizing the Large Eddy Simulation(LES)turbulence model and the Volume of Fluid(VOF)method within the OpenFOAM framework.Comparative analysis of results obtained at different angles of attack is undertaken.A discernible augmentation in cavity thickness is observed concomitant with the escalation in attack angle,alongside a progressive intensification in pressure at the leading edge of the hydrofoil,contributing to the suction force.These results can serve as a fundamental point of reference for gaining a deeper comprehension of cloud cavitation dynamics.

关键词： Cloud cavitation re-entrant jet compression wave clark-Y hydrofoil

The autophagy protein Atg9 functions in glia and contributes to parkinsonian symptoms in a Drosophila model of Parkinson’s disease

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Neural Regeneration Research 2024年第5期19卷 1150-1155页

作者： Shuanglong Yi Linfang Wang Margaret S.Ho shiping Zhang School of Life Science and Technology ShanghaiTech UniversityShanghaiChina College of Life Sciences University of Chinese Academy of SciencesBeijingChina

Parkinson’s disease is a progressive neurodegenerative disease characterized by motor deficits,dopaminergic neuron loss,and brain accumulation ofα-synuclein aggregates called Lewy bodies.Dysfunction in protein degradation pathways,such as autophagy,has been demonstrated in neurons as a critical mechanism for eliminating protein aggregates in Parkinson’s disease.However,it is less well understood how protein aggregates are eliminated in glia,the other cell type in the brain.In the present study,we show that autophagy-related gene 9(Atg9),the only transmembrane protein in the autophagy machinery,is highly expressed in Drosophila glia from adult brain.Results from immunostaining and live cell imaging analysis reveal that a portion of Atg9 localizes to the trans-Golgi network,autophagosomes,and lysosomes in glia.Atg9 is persistently in contact with these organelles.Lacking glial atg9 reduces the number of omegasomes and autophagosomes,and impairs autophagic substrate degradation.This suggests that glial Atg9 participates in the early steps of autophagy,and hence the control of autophagic degradation.Importantly,loss of glial atg9 induces parkinsonian symptoms in Drosophila including progressive loss of dopaminergic neurons,locomotion deficits,and glial activation.Our findings identify a functional role of Atg9 in glial autophagy and establish a potential link between glial autophagy and Parkinson’s disease.These results may provide new insights on the underlying mechanism of Parkinson’s disease.

关键词： Atg9 autophagy glia Parkinson’s disease

Privacy Protection for Blockchain-Based Healthcare IoT Systems:A Survey

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IEEE/CAA Journal of Automatica Sinica 2024年第8期 1757-1776页

作者： Minfeng Qi Ziyuan Wang Qing-Long Han Jun Zhang shiping Chen yang Xiang the School of Science Computing and Engineering Technologies Swinburne University of Technology the Faculty of Data Science City University of Macau School of Science Computing and Engineering Technologies Swinburne University of Technology IEEE CSIRO Data61

To enable precision medicine and remote patient monitoring, internet of healthcare things(IoHT) has gained significant interest as a promising technique. With the widespread use of IoHT, nonetheless, privacy infringements such as IoHT data leakage have raised serious public concerns. On the other side, blockchain and distributed ledger technologies have demonstrated great potential for enhancing trustworthiness and privacy protection for IoHT systems. In this survey, a holistic review of existing blockchain-based IoHT systems is conducted to indicate the feasibility of combining blockchain and IoHT in privacy protection. In addition, various types of privacy challenges in IoHT are identified by examining general data protection regulation(GDPR). More importantly, an associated study of cutting-edge privacy-preserving techniques for the identified IoHT privacy challenges is presented. Finally, several challenges in four promising research areas for blockchain-based IoHT systems are pointed out, with the intent of motivating researchers working in these fields to develop possible solutions.

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A Deep Learning-Enabled Skin-Inspired Pressure Sensor for Complicated Recognition Tasks with Ultralong Life

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Research 2024年第1期2023卷 443-454页

作者： Yingxi Xie Xiaohua Wu Xiangbao Huang Qinghua Liang shiping Deng Zeji Wu Yunpeng Yao Longsheng Lu School of Mechanical&Automotive Engineering South China University of TechnologyGuangzhouChina

Flexible full-textile pressure sensor is able to integrate with clothing directly,which has drawn extensive attention from scholars recently.But the realization of flexible full-textile pressure sensor with high sensitivity,wide detection range,and long working life remains challenge.Complex recognition tasks necessitate intricate sensor arrays that require extensive data processing and are susceptible to damage.The human skin is capable of interpreting tactile signals,such as sliding,by encoding pressure changes and performing complex perceptual tasks.Inspired by the skin,we have developed a simple dip-and-dry approach to fabricate a full-textile pressure sensor with signal transmission layers,protective layers,and sensing layers.The sensor achieves high sensitivity(2.16 kPa^(−1)),ultrawide detection range(0 to 155.485 kPa),impressive mechanical stability of 1 million loading/unloading cycles without fatigue,and low material cost.The signal transmission layers that collect local signals enable real-world complicated task recognition through one single sensor.We developed an artificial Internet of Things system utilizing a single sensor,which successfully achieved high accuracy in 4 tasks,including handwriting digit recognition and human activity recognition.The results demonstrate that skin-inspired full-textile sensor paves a promising route toward the development of electronic textiles with important potential in real-world applications,including human–machine interaction and human activity detection.

关键词： Deep Skin utilizing

A study of the soil water potential threshold values to trigger irrigation of ‘Shimizu Hakuto’ peach at pivotal fruit developmental stages

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Horticultural Plant Journal 2024年第2期10卷 376-386页

作者： Yusui Lou Yuepeng Han Yubin Miao Hongquan Shang Zhongwei Lv Lei Wang shiping Wang Horticulture Reseach Institute Henan Academy of Agricultural SciencesZhengzhouHenan 450002China School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical Garden of the Chinese Academy of SciencesWuhanHubei 430074China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Water management is an important practice that affects fruit size and quality.Effective implementation of irrigation scheduling requires knowledge of the appropriate indicators and thresholds,which are established manly based on the effects of water deficits on final fruit quality.Few studies have focused on the real-time effects of water status on fruit and shoot growth.To establish soil water potential (ψ_(soil)) thresholds to trigger irrigation of peach at pivotal fruit developmental stages,photogrammetry,^(13)C labelling,and other techniques were used in this study to investigate real-time changes in stem diameter,fruit projected area,net leaf photosynthetic rate (P_(n)),and allocation of photoassimilates to fruit under soil water potential conditions ranging from saturation to stress in 6-year-old Shimizu hakuto’peach.Stem growth,fruit growth,and P_n exhibited gradually decreasing sensitivity to water deficits during fruit developmental stages I,II,and III.Stem diameter growth was significantly inhibited whenψ_(soil)dropped to-8.5,-7.6,and-5.4 k Pa,respectively.Fruit growth rate was low,reaching zero when theψ_(soil)was-9.0 to-23.1,-14.9 to-21.4,and-16.5 to-23.3 k Pa,respectively,and P_ndecreased significantly when theψ_(soil)reached-24.2,-22.7,and-20.4 kPa,respectively.In addition,more photoassimilates were allocated to fruit under moderateψ_(soil)conditions (-10.1 to-17.0 k Pa) than under otherψ_(soil)values.Our results revealed threeψ_(soil)thresholds,-10.0,-15.0,and-15.0 kPa,suitable for triggering irrigation during stages I,II,and III,respectively.These thresholds can be helpful for controlling excessive tree vigor,maintaining rapid fruit growth and leaf photosynthesis,and promoting the allocation of more photoassimilates to fruit.

关键词： Peach Soil water potential Irrigation threshold Fruit expansion Photosynthesis

High-stability spherical lanthanide nanoclusters for magnetic resonance imaging

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National Science Review 2023年第4期10卷 123-132页

作者： Hai-Ling Wang Donglin Liu Jian-Hua Jia Jun-Liang Liu Ze-Yu Ruan Wei Deng shiping yang Si-Guo Wu Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of Chemistry Sun Yat-sen University College of Chemistry and Materials Science Shanghai Normal University

High-nuclear lanthanide clusters have shown great potential for the administration of high-dose mononuclear gadolinium chelates in magnetic resonance imaging(MRI). The development of high-nuclear lanthanide clusters with excellent solubility and high stability in water or solution has been challenging and is very important for expanding the performance of MRI. We used N-methylbenzimidazole-2-methanol(HL) and LnCl3·6H2O to synthesize two spherical lanthanide clusters, Ln32(Ln = Ho, Ho32; and Ln =Gd, Gd32), which are highly stable in solution. The 24 ligands L-are all distributed on the periphery of Ln32and tightly wrap the cluster core, ensuring that the cluster is stable. Notably, Ho32can remain highly stable when bombarded with different ion source energies in HRESI-MS or immersed in an aqueous solution of different pH values for 24 h. The possible formation mechanism of Ho32was proposed to be Ho(Ⅲ),(L)-and H2O → Ho3(L)3/Ho3(L)4→ Ho4(L)4/Ho4(L)5→ Ho6(L)6/Ho6(L)7→ Ho16(L)19→Ho28(L)15→ Ho32(L)24/Ho32(L)21/Ho32(L)23. To the best of our knowledge, this is the first study of the assembly mechanism of spherical high-nuclear lanthanide clusters. Spherical cluster Gd32, a form of highly aggregated Gd(Ⅲ), exhibits a high longitudinal relaxation rate(1 T, r1= 265.87 mM-1·s-1). More notably, compared with the clinically used commercial material Gd-DTPA, Gd32has a clearer and higher-contrast T1-weighted MRI effect in mice bearing 4T1 tumors. This is the first time that high-nuclear lanthanide clusters with high water stability have been utilized for MRI. High-nuclear Gd clusters containing highly aggregated Gd(Ⅲ) at the molecular level have higher imaging contrast than traditional Gd chelates; thus, using large doses of traditional gadolinium contrast agents can be avoided.

关键词： T1-weighted MRI lanthanide clusters high stability low toxicity assembly mechanism