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High-Order Decoupled and Bound Preserving Local Discontinuous Galerkin Methods for a Class of Chemotaxis Models

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Communications on Applied Mathematics and Computation 2024年第1期6卷 372-398页

作者： Wei zheng yan Xu School of Mathematical Sciences University of Science and Technology of ChinaHefei230026AnhuiChina

In this paper,we explore bound preserving and high-order accurate local discontinuous Galerkin(LDG)schemes to solve a class of chemotaxis models,including the classical Keller-Segel(KS)model and two other density-dependent problems.We use the convex splitting method,the variant energy quadratization method,and the scalar auxiliary variable method coupled with the LDG method to construct first-order temporal accurate schemes based on the gradient flow structure of the models.These semi-implicit schemes are decoupled,energy stable,and can be extended to high accuracy schemes using the semi-implicit spectral deferred correction method.Many bound preserving DG discretizations are only worked on explicit time integration methods and are difficult to get high-order accuracy.To overcome these difficulties,we use the Lagrange multipliers to enforce the implicit or semi-implicit LDG schemes to satisfy the bound constraints at each time step.This bound preserving limiter results in the Karush-Kuhn-Tucker condition,which can be solved by an efficient active set semi-smooth Newton method.Various numerical experiments illustrate the high-order accuracy and the effect of bound preserving.

关键词： Chemotaxis models Local discontinuous Galerkin(LDG)scheme Convex splitting method Variant energy quadratization method Scalar auxiliary variable method Spectral deferred correction method

Microscale spherical TiO_(2)powder prepared by hydrolysis of TiCl_(4)solution:Synthesis and kinetics

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Particuology 2024年第1期84卷 60-71页

作者： Peiyi yan Ying Zhang Shili zheng School of Rare earths University of Science and Technology of ChinaHefei230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China Key Laboratory of Green Process and engineering National Engineering Research Center of Green Recycling for Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing100190China State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization Panzhihua617000China

Hydrolysis of TiCl_(4)solution is capable of preparing microscale TiO_(2)particles.This research studied the synthesis of microscale spherical TiO_(2)powders and the hydrolysis kinetics.The effects of the flow field generated by different agitators and baffles in the crystallizer,the initial free acid concentration,the initial equivalent TiO_(2)concentration,and the temperature on the hydrolysis progress and powder morphology were systematically studied.The results show that the flow field in a crystallizer can significantly affect the morphology and particle size of the powders,and the axial flow can improve the sphericity of the powders.The increased free HCl and equivalent TiO_(2)concentrations in the pregnant solution inhibit the forward hydrolysis reaction,prolong the time to reach equilibrium,and reduce the yield.An appropriate temperature matching the compositions of the pregnant solution is crucial for the powder morphology and size.Powders with sizes ranging from around 5 um-40μm can be tuned under controlled flow field,solution compositions,and temperature conditions.In addition,the Cheng and Wunderlich modified Avrami equation was used for the crystallization kinetic modeling.The effects of the free HCl concentration,equivalent TiO_(2)concentration,and hydrolysis temperature are reflected in the reaction rate constant and active nuclei reduction index.Increasing the free HCl and equivalent TiO_(2)concentrations will reduce the reaction rate constant and accelerate the deactivation of the active nuclei,thus increasing the final powder size,while increasing the temperature will lead to the opposite results.

关键词： TiCl_(4) Hydrolysis Microscale TiO_(2) Spherical Kinetics

efficacy of scraping therapy on blood pressure and sleep quality in stage Ⅰ and Ⅱ essential hypertension: A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第1期22卷 12-21页

作者： zheng-gang Zhu Jian-ru Wang Xiao-yan Pan School of Nursing Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina School of Health Sciences Universiti Sains MalaysiaKubang Kerian 16150KelantanMalaysia Department of Cardiovascular Medicine the First Affiliated Hospital of Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina

Background Scraping therapy is widely used in treating stage I and II essential hypertension in China.However,there has been no systematic evaluation of the efficacy of scraping therapy on blood pressure and sleep quality in stage I and II essential hypertension.Search strategy Seven electronic databases(PubMed,Scopus,Cochrane Library,Web of Science,eBSCO,China National Knowledge Infrastructure and Wanfang Data electronic databases)were searched from inception to December 2022.Based on the principle of combining subject words with text words,the search strategy was constructed around search terms for“scraping therapy,”“scraping,”“Guasha,”“Gua sha,”“hypertension,”and“high blood pressure”during the database searches.Inclusion criteria Randomized controlled trials(RCTs)were included if they recruited patients with stage I and II essential hypertension and included a scraping therapy intervention.The intervention group received antihypertensive drugs and scraping therapy,while the control group only took antihypertensive drugs.Data extraction and analysis Review Manager 5.4.0 and STATA 15.1 were used to enter all the relevant outcome variables to conduct the meta-analysis.The quality of the selected RCTs was assessed using the PeDro scale.The sensitivity analysis was carried out by iteratively excluding individual studies and repeating the analysis to determine the stability of the findings and identify any studies with greater influence on the outcome.Subgroup analysis was performed to find the source of heterogeneity.Funnel plots were used to evaluate the publication bias of included studies.Results Nine RCTs including 765 participants were selected.Meta-analysis showed that scraping therapy combined with medication had an advantage over the use of medication alone in lowering systolic blood pressure(mean difference[MD]=?5.09,95%confidence interval[CI]=?6.50 to?3.67,Pessure(MD=?2.66,95%CI=?3.17 to?2.14,Ped that scraping therapy improved sleep quality in mid

关键词： Scraping therapy essential hypertension efficacy Blood pressure Sleep quality Systematic review Meta-analysis

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Heterogeneous Image Knowledge Driven Visual Perception

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Ieee/CAA Journal of Automatica Sinica 2024年第1期11卷 255-257页

作者： Lan yan Wenbo zheng Fei-Yue Wang Ieee the College of Computer Science and electronic engineering Hunan UniversityChangsha 410082China the School of Computer Science and Artificial Intelligence Wuhan University of TechnologyWuhan 430070China the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China

Dear editor,This letter is concerned with visual perception closely related to heterogeneous images.Facing the huge challenge brought by different image modalities,we propose a visual perception framework based on heterogeneous image knowledge,i.e.,the domain knowledge associated with specific vision tasks,to better address the corresponding visual perception problems.

关键词： Visual visual knowledge

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effect of ginsenoside Rg1 on hematopoietic stem cells in treating aplastic anemia in mice via MAPK pathway

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World Journal of Stem Cells 2024年第5期16卷 591-603页

作者： Jin-Bo Wang Ming-Wei Du yan zheng Internal Medicine of Traditional Chinese Medicine Tongde Hospital of Zhejiang ProvinceHangzhou 310012Zhejiang ProvinceChina Institute of Cardiovascular Disease Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Shanghai Key Laboratory of Molecular Medical Mycology Second Affiliated Hospital of Naval Medical UniversityShanghai 200003China Shanghai Key Laboratory of Traditional Chinese Clinical Medicine Shanghai 201203China Department of Hepatic The Xixi Hospital of Hangzhou Affiliated to Zhejiang University of Traditional Chinese MedicineHangzhou 310023Zhejiang ProvinceChina

BACKGROUND Aplastic anemia(AA)presents a significant clinical challenge as a life-threatening condition due to failure to produce essential blood cells,with the current the-rapeutic options being notably limited.AIM To assess the therapeutic potential of ginsenoside Rg1 on AA,specifically its protective effects,while elucidating the mechanism at play.MeTHODS We employed a model of myelosuppression induced by cyclophosphamide(CTX)in C57 mice,followed by administration of ginsenoside Rg1 over 13 d.The invest-igation included examining the bone marrow,thymus and spleen for pathological changes via hematoxylin-eosin staining.Moreover,orbital blood of mice was collected for blood routine examinations.Flow cytometry was employed to identify the impact of ginsenoside Rg1 on cell apoptosis and cycle in the bone marrow of AA mice.Additionally,the study further evaluated cytokine levels with enzyme-linked immunosorbent assay and analyzed the expression of key proteins in the MAPK signaling pathway via western blot.ReSULTS Administration of CTX led to significant damage to the bone marrow’s structural integrity and a reduction in hematopoietic cells,establishing a model of AA.Ginsenoside Rg1 successfully reversed hematopoietic dysfunction in AA mice.In comparison to the AA group,ginsenoside Rg1 provided relief by reducing the induction of cell apoptosis and inflammation factors caused by CTX.Furthermore,it helped alleviate the blockade in the cell cycle.Treatment with ginsenoside Rg1 significantly alleviated myelosuppression in mice by inhibiting the MAPK signaling pathway.CONCLUSION This study suggested that ginsenoside Rg1 addresses AA by alleviating myelosuppression,primarily through modulating the MAPK signaling pathway,which paves the way for a novel therapeutic strategy in treating AA,highlighting the potential of ginsenoside Rg1 as a beneficial intervention.

关键词： Aplastic anemia Ginsenoside Rg1 Myelosuppression MAPK signaling pathway Bone marrow Hematopoietic stem cells

Multi-Smart Meter Data encryption Scheme Basedon Distributed Differential Privacy

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Big Data Mining and Analytics 2024年第1期7卷 131-141页

作者： Renwu yan yang zheng Ning Yu Cen Liang School of electronic Electrical Engineering and PhysicsFujian University of TechnologyFuzhou 350118China Department of Computing Sciences at The College at Brockport State University of New YorkNew YorkNY 14420USA

Under the general trend of the rapid development of smart grids,data security and privacy are facing serious challenges;protecting the privacy data of single users under the premise of obtaining user-aggregated data has attracted widespread attention.In this study,we propose an encryption scheme on the basis of differential privacy for the problem of user privacy leakage when aggregating data from multiple smart meters.First,we use an improved homomorphic encryption method to realize the encryption aggregation of users’data.Second,we propose a double-blind noise addition protocol to generate distributed noise through interaction between users and a cloud platform to prevent semi-honest participants from stealing data by colluding with one another.Finally,the simulation results show that the proposed scheme can encrypt the transmission of multi-intelligent meter data under the premise of satisfying the differential privacy mechanism.even if an attacker has enough background knowledge,the security of the electricity information of one another can be ensured.

关键词： smart grid homomorphic encryption data aggregation differential privacy cloud computing

Miniaturized, Wide Stopband Filter Based on Shielded Capacitively Loaded SIW Resonators

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Chinese Journal of electronics 2024年第2期33卷 456-462页

作者： yan zheng Hanyu TIAN Yuandan DONG University of electronic Science and Technology of China (UeSTC)

Based on the full-mode capacitively loaded substrate integrated waveguide（SIW） resonator and the miniaturized shielded half-mode capacitively loaded SIW（S-HMCSIW） cavities, a novel compact high-performance filter is proposed. The footprint of the half-mode SIW（HMSIW） is further reduced due to the application of the capacitive-loading technique. By applying cross coupling, the proposed SIW filter's transmission zero enhances the stopband rejection and shows excellent selectivity. For the bandpass filter, the measured |S21| and |S11| are better than 1.09 d B and-14 d B, respectively. And a 3-d B fractional bandwidth（FBW） of 9.14–10.76 GHz（FBW=16.2%）is also observed. The filter achieves a wide stopband with a-20 d B out-of-band rejection up to 2.69f0（f0= 10 GHz）,with a size of 0.39λg× 0.51λgonly. Good agreement between measurement and simulation is obtained.

关键词： Bandpass filter Capacitively loaded Compact filter Shielded cavity Substrate integrated waveguide (SIW)

Structural characterization of three acidic polysaccharides from Opuntia dillenii Haw.fruits and their protective effect against hydrogen peroxide-induced oxidative stress in Huh-7 cells

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Food Science and Human Wellness 2024年第4期13卷 1929-1942页

作者： Rui Liu Fangxin Chu zheng yan Hanqing Chen School of Food and Biological engineering Hefei University of TechnologyHefei 230601China engineering Research Center of Bio-Process Ministry of EducationHefei University of TechnologyHefei 230601China

Three novel acidic polysaccharide fractions(OFPP-1,OFPP-2,OFPP-3)with different m olecular weights(803.7,555.1 and 414.5 k Da)were isolated from the peeled Opuntia dillenii Haw.fruits by alkali-extraction,graded alcohol precipitation and column chromatography.Structural analysis indicated that OFPPs were pectic polysaccharides consisting of rhamnose,arabinose and galactose residues.The backbone of OFPP-1 consisted of a repeating unit→6-α-D-Galp A-(1→2)-α-L-Rhap-(1→with T-α-D-Galp A-(1→6)-α-D-Galp A-(1→4)-α-D-Glcp-(1→,T-β-D-Xylp-(1→6)-α-D-Galp A-(1→4)-α-D-Glcp-(1→or T-α-D-Galp A-(1→3)-α-L-Araf-(1→as the side chains.The backbone of OFPP-2 consisted of a disaccharide repeating unit→2)-α-L-Rhap-(1→4)-β-D-Galp A-(1→with T-β-L-Araf-(1→as the branches substituted at the O-4 position of→2,4)-α-LRhap-(1→.Whereas the backbone of OFPP-3 was→2,4)-α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-β-L-Araf-(1→or→2,4)-α-L-Rhap-(1→2)-α-L-Rhap-(1→4)-β-D-Galp A-(1→,which was branched at the O-4 position of→2,4)-α-L-Rhap-(1→.Moreover,these three polysaccharide fractions could protect Huh-7 cells against H2O2-induced oxidative stress to different extents by decreasing the MDA content and increasing the SOD,CAT,GSH-Px activities and the GSH level in the Huh-7 cells.These results suggest that OFPPs have the potential to be used as natural antioxidants.

关键词： Opuntia dillenii Haw.fruits Polysaccharide Alkali extraction Structural characterization Oxidative stress

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Multi-time Collaborative Restoration for Integrated electrical-gas Distribution Systems Based on Rolling Optimization

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CSee Journal of Power and energy Systems 2024年第2期10卷 660-671页

作者： Jingyang Yun zheng yan Yun Zhou Peichao Zhang Weidong Hu Key Laboratory of Control of Power Transmission and Conversion of Ministry of education Department of Electrical EngineeringShanghai Jiao Tong University

This paper proposes a multi-time collaborative restoration model for integrated electricity-gas distribution sys-tems(IeGDSs)considering multiple resources after extreme weather events.Based on the linearized power flow constraints of the unbalanced electrical distribution system(eDS)and gas distribution system(GDS),this problem can be formulated as a mixed-integer linear programming(MILP)model.To improve the efficiency and veracity of the solution,a rolling optimiza-tion based two-stage method is developed with the first stage solved by a linear approximation model,and the second stage solved by real-time updated rolling optimization.By solving the MILP problem using rolling optimization,the proposed model and solution method achieve efficient and reliable collaborative restoration of IeGDS considering multiple resources and unbal-anced operation characteristics of eDS.The effectiveness of the proposed model and method is validated by using an IeGDS made of a 37-bus unbalanced eDS and 11-node GDS.Index Terms-electricity-gas system,mix-integer linear programming,power system restoration.

关键词： electricity-gas system mix-integer linear programming power system restoration