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Recognition of Organizational Morphology of Mesoscale Convective Systems Using Himawari-8 Observations

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Journal of Tropical Meteorology 2024年第3期30卷 289-305页

作者： SHOU yi-xuan ZHANG Su-zhao lu Feng Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites National Satellite Meteorological Center(National Center for Space Weather)China Meteorological AdministrationBeijing 100081 China Innovation Center for FengYun Meteorological Satellite(FYSIC) Beijing 100081 China Key Laboratory for Meteorological Disaster Monitoring and Early Warning and Risk Management of Characteristic Agriculture in Arid Regions Yinchuan 750002 China Ningxia Key Laboratory of Meteorological Disaster Prevention and Mitigation Yinchuan 750002 China

The onset,evolution,and propagation processes of convective cells can be reflected by the organizational morphology of mesoscale convective systems(MCSs),which are key factors in determining the potential for heavy *** paper proposed a method for objectively classifying and segmenting MCSs using geosynchronous satellite *** of the product relative to the classification in radar composite reflectivity imagery indicates that the algorithm offers skill for discriminating between convective and stratiform areas and matched 65%of convective area identifications in radar imagery with a false alarm rate of 39%and an accuracy of 94%.A quantitative evaluation of the similarity between the structures of 50 MCSs randomly obtained from satellite and radar observations shows that the similarity was as high as 60%.For further testing,the organizational modes of the MCS that caused the heavy precipitation in Northwest China on August 21,2016(hereinafter known as the“0821”rainstorm)were *** was found that the MCS,accompanied by the“0821”rainstorm,successively exhibited modes of the isolated cell,squall line with parallel stratiform(PS)rain,and non-linear system during its life *** them,the PS mode might have played a key role in causing this *** findings are in line with previous studies.

关键词： mesoscale convective system satellite organizational morphology extremely heavy precipitation

Transient Damping of Virtual Synchronous Generator for Enhancing Synchronization Stability during Voltage Dips

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CES Transactions on Electrical Machines and Systems 2024年第2期8卷 143-151页

作者： Shitao Sun Yu Lei Guowen Hao yi lu Jindong Liu Zhaoxin Song Jie Zhang North China Electric Power Research Institute Co. Ltd.Beijing 100045China State Grid Xinyuan Co. Ltd.Beijing 100761China Hebei Fengning Pumped Storage Energy Co.Ltd. Chengde 068350China

Virtual synchronous generators(VSGs)are widely introduced to the renewable power generation,the variablespeed pumped storage units,and so on,as a promising gridforming *** is noted that VSGs can provide virtual inertia for frequency support,but the larger inertia would worsen the synchronization stability,referring to keeping synchronization with the grid during voltage ***,this paper presents a transient damping method of VSGs for enhancing the synchronization stability during voltage *** is revealed that the loss of synchronization(LOS)of VSGs always accompanies with the positive frequency deviation and the damping is the key factor to remove LOS when the equilibrium point *** order to enhance synchronization stability during voltage dips,the transient damping is proposed,which is generated by the frequency deviation in active power ***,the proposed method can realize seamless switching between normal state and grid ***,detailed control design for transient damping gain is given to ensure the synchronization stability under different inertia requirements during voltage ***,the experimental results are presented to validate the analysis and the effectiveness of the improved transient damping method.

关键词： Virtual synchronous generator(VSG) Transient damping Synchronization stability Voltage dips

Treatment with intravenous alteplase in ischaemic stroke patients with onset time between 4.5 and 24 hours(HOPE):protocol for a randomised,controlled,multicentre study

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Stroke & Vascular Neurology 2024年第3期9卷 318-323,I0274-I0282页

作者： Zhongyu luo ying Zhou Yaode He Shenqiang Yan Zhicai Chen Xuting Zhang yi Chen lu-Sha Tong Wansi Zhong Haitao Hu Kemeng Zhang Jiansheng Yang Bruce C V Campbell Min Lou Department of Neurology Zhejiang University School of Medicine Second Affiliated HospitalHangzhouZhejiangChina Department of Medicine and Neurology Melbourne Brain Centre at Royal Melbourne HospitalParkvilleVictoriaAustralia

Background While intravenous thrombolysis is recommended for patients who had an acute ischaemic stroke(AIS)within 4.5hours of symptom onset,there are few randomised trials investigating the benefits of thrombolysis beyond this therapeutic *** To determine whether patients who had an AIS selected with the presence of potentially salvageable tissue on CT perfusion at 4.5–24hours after stroke onset(for stroke with unknown onset time,the midpoint of the time last known to be well and symptom recognition time;for wake-up stroke,the midpoint of the time last known to be well or sleep onset and wake up time)will benefit from intravenous *** HOPE is a prospective,multicentre,randomised,open-label blinded endpoint trial with the stage of phase *** treatment allocation employs 1:1 *** treatment arm under investigation is alteplase with standard therapy,the control arm is standard *** imaging criteria include ischaemic core volume≤70mL,penumbra≥10mL and mismatch≥20%.Study outcomes The primary outcome is non-disabled functional outcome(assessed as modified Rankin Scale score of 0–1 at 90 days).Discussion HOPE is the first trial to investigate whether intravenous thrombolysis with alteplase offers benefits in patients who had an AIS presenting within 4.5–24hours,which has the potential to extend time window and expand eligible population for thrombolysis therapy.

关键词： patients intravenous centre

Potential application of Nardostachyos Radix et Rhizoma-Rhubarb for the treatment of diabetic kidney disease based on network pharmacology and cell culture experimental verification

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World Journal of Diabetes 2024年第3期15卷 530-551页

作者： Meng-ying Che Ling Yuan Jiao Min Duo-Jie Xu Dou-Dou lu Wen-Jing Liu Kai-Li Wang Yan-Yan Wang yi Nan Key Laboratory of Ningxia Minority Medicine Modernization Ministry of Education Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina College of Pharmacy Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Traditional Chinese Medicine College Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina School of Clinical Medicine Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Department of Endocrinology Yinchuan Hospital of Traditional Chinese MedicineYinchuan 750004Ningxia Hui Autonomous RegionChina

BACKGROUND Diabetic kidney disease(DKD)is one of the serious complications of diabetes mellitus,and the existing treatments cannot meet the needs of today's *** Chinese medicine has been validated for its efficacy in DKD after many years of clinical ***,the specific mechanism by which it works is still *** the molecular mechanism of the Nardostachyos Radix et Rhizoma-rhubarb drug pair(NRDP)for the treatment of DKD will provide a new way of thinking for the research and development of new *** To investigate the mechanism of the NRDP in DKD by network pharmacology combined with molecular docking,and then verify the initial findings by in vitro *** The Traditional Chinese Medicine Systems Pharmacology(TCMSP)database was used to screen active ingredient targets of *** for DKD were obtained based on the Genecards,OMIM,and TTD *** VENNY 2.1 database was used to obtain DKD and NRDP intersection targets and their Venn diagram,and Cytoscape 3.9.0 was used to build a"drug-component-target-disease"*** String database was used to construct protein interaction *** Encyclopedia of Genes and Genomes(KEGG)enrichment analysis and Gene Ontology analysis were performed based on the DAVID *** selecting the targets and the active ingredients,Autodock software was used to perform molecular *** experimental validation using renal tubular epithelial cells(TCMK-1),we used the Cell Counting Kit-8 assay to detect the effect of NRDP on cell viability,with glucose solution used to mimic a hyperglycemic *** cytometry was used to detect the cell cycle progression and *** blot was used to detect the protein expression of STAT3,p-STAT3,BAX,BCL-2,Caspase9,and *** A total of 10 active ingredients and 85 targets with 111 disease-related signaling pathways were obtained for *** analysis of KEGG pathways was performed to determ

关键词： Nardostachyos Radix et Rhizoma-rhubarb Diabetic kidney disease Molecular docking Network pharmacology Experimental validation

Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

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National Science Review 2024年第2期11卷 155-167页

作者： Peng He Meng-Yang Hu Jin-Hong Li Tian-Zhang Qiao yi-Lin lu Shou-Fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

Layered Potassium Titanium Niobate/Reduced Graphene Oxide Nanocomposite as a Potassium‑Ion Battery Anode

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Nano-Micro Letters 2024年第1期16卷 1-16页

作者： Charlie A.F.Nason Ajay Piriya Vijaya Kumar Saroja yi lu Runzhe Wei Yupei Han Yang Xu Department of Chemistry University College London20 Gordon StreetLondon WC1H 0AJUK

With graphite currently leading as the most viable anode for potassium-ion batteries(KIBs),other materials have been left relatively *** metal oxides are among these,with many positive attributes such as synthetic maturity,longterm cycling stability and fast redox ***,to address this research deficiency we report herein a layered potassium titanium niobate KTiNbO5(KTNO)and its rGO nanocomposite(KTNO/rGO)synthesised via solvothermal methods as a high-performance anode for *** effective distribution across the electrically conductive rGO,the electrochemical performance of the KTNO nanoparticles was *** potassium storage performance of the KTNO/rGO was demonstrated by its first charge capacity of 128.1 mAh g^(−1) and reversible capacity of 97.5 mAh g^(−1) after 500 cycles at 20 mA g^(−1),retaining 76.1%of the initial capacity,with an exceptional rate performance of 54.2 mAh g^(−1)at 1 A g^(−1).Furthermore,to investigate the attributes of KTNO in-situ XRD was performed,indicating a low-strain ***-situ X-ray photoelectron spectra further investigated the mechanism of charge storage,with the titanium showing greater redox reversibility than the *** work suggests this lowstrain nature is a highly advantageous property and well worth regarding KTNO as a promising anode for future high-performance KIBs.

关键词： Potassium-ion batteries Intercalation Transition metal oxides Anodes Nanocomposite

Nanoscale“precision strike”:Tumor microenvironment-responsive smart micelles for efficient targeted drug delivery

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Nano Research 2024年第9期17卷 8360-8367页

作者： Dong Wan Yarong Song Xiujuan lu Yanfeng Huang Jianxin Zhang Yonghui Liu yi Liu Jie Pan School of Chemistry Tiangong UniversityTianjin 300387China School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387China

To address the limitations of conventional nanotechnology-based drug delivery systems,this work developed enzyme and reduction dual-responsive polymeric *** micelles were synthesized with copolymers composed of TPGS_(3350)-PVGLIG-DOX(TPD)and FA-SS-DOX(FSD),which endow them with tumor-targeted drug delivery ***_(3350)contributes to extending the circulation of micelles in body,augmenting their accumulation in tumor tissues via the enhanced permeability and retention(EPR)*** localized the tumor site,matrix metalloproteinase 2(MMP2)cleaves the PVGLIG peptide moiety within the micelles,thereby releasing TPGS_(3350)and exposing the targeting ligand of *** approach enables the subsequent internalization of the micelles by tumor cells through folate receptor-mediated *** internalization,the high intracellular concentration of glutathione(GSH)triggers the reduction of the disulfide bond within the FA-SS-DOX,leading to the release of the anticancer-drug doxorubicin(DOX),which promotes apoptosis in the tumor cells and enhances the efficacy of chemotherapy.

关键词： cancer peptide micelle dual-responsive folate

Single-source-precursor synthesis and air-plasma ablation behavior of(Ti,Zr,Hf)C/SiC ceramic nanocomposites at 2200℃

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Journal of Advanced Ceramics 2024年第7期13卷 1043-1059页

作者： Li lu Qingbo Wen Jinrun Hu Tianxing Jiang Xiangchao Ren Yalei Wang yi Zeng Xiang Xiong State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Dense monolithic(Ti,Zr,Hf)C/SiC ceramic nanocomposites with four different molar ratios of metallic elements in the(Ti,Zr,Hf)C phase(i.e.,Ti:Zr:Hf=1:1:1,2:3:5,2:3:3,and 1:2:1)were prepared upon pyrolysis of novel(Ti,Zr,Hf)-containing single-source precursors(SSPs),followed by spark plasma sintering(SPS).A thorough characterization was conducted to elucidate the synthesis of the SSPs,polymer-to-ceramic transformation,chemical/phase compositions,and microstructure of the SiTiZrHfC-based *** results revealed the feasibility of synthesizing nanocomposites with high(Ti,Zr,Hf)C contents using the SSP *** nanocomposites were characterized by a unique microstructure with in situ generated(Ti,Zr,Hf)C@C core-shell nanoparticles homogeneously mixed withβ-*** ablation behavior of the nanocomposites was evaluated on an air-plasma device for 60 ***,the nanocomposites exhibited excellent ablation resistance,and the lowest linear ablation rate reached−0.58μm/s at 2200°***,the ablation resistance can be dramatically improved by precisely tailoring the atomic ratios of metal elements within the(Ti,Zr,Hf)C phase via the molecular design of the *** formation of a multiple-oxide layer with both a high-meltingpoint phase((Ti,Zr,Hf)O_(2))and low-melting-point phases((Zr,Hf)TiO_(4))and glassy SiO_(2),as well as their structure,played a critical role in the enhanced ablation *** uniform distribution of the high-melting-point(Ti,Zr,Hf)O_(2)nano/microparticles throughout the glassy SiO_(2)matrix significantly enhanced the viscosity and stability of the oxide layer by the pinning effect,offering superior protection against the ingress of oxygen atoms and excellent resistance to mechanical erosion.

关键词： ultrahigh-temperature ceramics(UHTCs) multicomponent carbide nanocomposites ablation behavior multiple oxides

6DOF pose estimation of a 3D rigid object based on edge-enhanced point pair features

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Computational Visual Media 2024年第1期10卷 61-77页

作者： Chenyi Liu Fei Chen lu Deng Renjiao yi Lintao Zheng Chenyang Zhu Jia Wang Kai Xu College of Computing National University of Defense TechnologyChangsha410073China Department of Spine Surgery the Second Xiangya HospitalCentral South UniversityChangsha410011China Clinical Nursing Teaching and Research Section the Second Xiangya HospitalChangsha410011China College of Meteorology and Oceanography National University of Defense TechnologyChangsha410073China Beijing Institute of Tracking and Communication Technology Beijing100094China

The point pair feature(PPF)is widely used for 6D pose *** this paper,we propose an efficient 6D pose estimation method based on the PPF *** introduce a well-targeted down-sampling strategy that focuses on edge areas for efficient feature extraction for complex geometry.A pose hypothesis validation approach is proposed to resolve ambiguity due to symmetry by calculating the edge matching *** perform evaluations on two challenging datasets and one real-world collected dataset,demonstrating the superiority of our method for pose estimation for geometrically complex,occluded,symmetrical *** further validate our method by applying it to simulated punctures.

关键词： point pair feature(PPF) pose estimation object recognition 3D point cloud