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Multiscale Characteristics and Connection Mechanisms of Attraction Networks:A Trajectory Data Mining Approach Leveraging Geotagged Data

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Chinese Geographical Science 2024年第3期34卷 533-547页

作者： JIANG Hongqiang wei ye MEI Lin WANG Zhaobo School of Resource and Environment Engineering Ludong UniversityYantai 264025China School of Geographical Sciences Northeast Normal UniversityChangchun 130024China Changchun University of Finance and Economics Changchun 130122China Jilin Jizhi City Architectural Design Co. LTDChangchun 130012China

Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and connection mechanisms of attraction networks is important for understanding the linkages between attractions and even the future destination planning.This paper uses geotagging data to compare the links between attractions in Beijing,China during four different periods:the pre-Olympic period(2004–2007),the Olympic Games and subsequent‘heat period’(2008–2013),the post-Olympic period(2014–2019),and the COVID-19(Corona Virus Disease 2019)pandemic period(2020–2021).The aim is to better understand the evolution and patterns of attraction networks at different scales in Beijing and to provide insights for tourism planning in the destination.The results show that the macro,meso-,and microscales network characteristics of attraction networks have inherent logical relationships that can explain the commonalities and differences in the development process of tourism networks.The macroscale attraction network degree Matthew effect is significant in the four different periods and exhibits a morphological monocentric structure,suggesting that new entrants are more likely to be associated with attractions that already have high value.The mesoscale links attractions according to the common purpose of tourists,and the results of the community segmentation of the attraction networks in the four different periods suggest that the functional polycentric structure describes their clustering effect,and the weak links between clusters result from attractions bound by incomplete information and distance,and the functional polycentric structure with a generally more efficient network of clusters.The pattern structure at the microscale reveals the topological transformation relationship of the regional collaboration pattern,and the attraction network structure in the four different periods has a very similar importance prof

关键词： attraction network travel mobility polycentric structure network motif connectivity mechanism destination management organization(DMO) destination planning Beijing,China

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Soft coarse-grained particle model for particle-fluid systems

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Particuology 2024年第1期84卷 178-193页

作者： Yanhao ye Ji Xu wei Ge State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing100190China

By modeling a group of neighboring real particles as a single coarse-grained particle(CGP),discrete particle method(DPM)is now capable of simulating industrial-scale particle-fluid systems.However,a systematic approach to determine the CGP properties and develop their interaction models is still lacking,which casts uncertainty on the predictivity of the method.In this study,collisions between predefined particle groups are analyzed to construct kernel functions for modeling the CGPs and then the model parameters are determined by equating the statistical properties of the CGPs and the real particles in the physical process studied.This approach is implemented for homogeneous cooling of granular gas,then demonstrated effective in simulating experimental fluidized beds.

关键词： Coarse-grain(CG) Discrete particle method(DPM) Fluidized bed Multi-scale simulation

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Intravitreal conbercept injection with panretinal photocoagulation for high-risk proliferative diabetic retinopathy with vitreous hemorrhage

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1066-1072页

作者： Yao Xu Qing ye wei Shen Department of Ophthalmology the Fourth Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina Department of Ophthalmology Suzhou Kowloon HospitalShanghai Jiao Tong University School of MedcineSuzhou 215000Jiangsu ProvinceChina Department of Ophthalmology the First Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina

AIM:To assess the clinical efficacy and safety of combining panretinal photocoagulation(PRP)with intravitreal conbercept(IVC)injections for patients with high-risk proliferative diabetic retinopathy(HR-PDR)complicated by mild or moderate vitreous hemorrhage(VH),with or without diabetic macular edema(DME).METHODS:Patients diagnosed with VH with/without DME secondary to HR-PDR and received PRP combined with IVC injections were recruited in this retrospective study.Upon establishing the patient’s diagnosis,an initial IVC was performed,followed by prompt administration of PRP.In cases who significant bleeding persisted and impeded the laser operation,IVC was sustained before supplementing with PRP.Following the completion of PRP,patients were meticulously monitored for a minimum of six months.Laser therapy and IVC injections were judiciously adjusted based on fundus fluorescein angiography(FFA)results.Therapeutic effect and the incidence of adverse events were observed.RESULTS:Out of 42 patients(74 eyes),29 were male and 13 were female,with a mean age of 59.17±12.74y(33-84y).The diabetic history was between 1wk and 26y,and the interval between the onset of visual symptoms and diagnosis of HR-PDR was 1wk-1y.The affected eye received 2.59±1.87(1-10)IVC injections and underwent 5.5±1.02(4-8)sessions of PRP.Of these,68 eyes received PRP following 1 IVC injection,5 eyes after 2 IVC injections,and 1 eye after 3 IVC injections.Complete absorption of VH was observed in all 74 eyes 5-50wk after initial treatment,with resolution of DME in 51 eyes 3-48wk after initial treatment.A newly developed epiretinal membrane was noted in one eye.Visual acuity significantly improved in 25 eyes.No complications such as glaucoma,retinal detachment,or endophthalmitis were reported.CONCLUSION:The study suggests that the combination of PRP with IVC injections is an effective and safe modality for treating diabetic VH in patients with HR-PDR.

关键词： conbercept panretinal photocoagulation high-risk proliferative diabetic retinopathy vitreous hemorrhage

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3D coarse-grained DPM simulation of the MIP reaction-regeneration loop

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Particuology 2024年第6期89卷 57-66页

作者： Yanhao ye Shuai Zhang Ji Xu wei Ge State Key Laboratory of Mesoscience and Engineering(formerly State Key Laboratory of Multiphase Complex Systems) Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

The reactor-regenerator loop is the core facility of the maximizing iso-paraffin(MIP)process.Although the discrete particle method(DPM)simulation can provide detailed information at the particle scale,it has been unable to simulate such a complex loop system due to limitations of coarse-grained(CG)models,computing software,and hardware.In this study,a newly proposed soft-shell CG-DPM model with a CG ratio of up to 800 is used to simulate a 3.5 Mt/a industrial-scale MIP reactor-regenerator loop.The solid fraction distribution obtained is found to agree well with in-situ measurements.Hydrodynamic properties including the distribution of solid fraction,gas and solid velocity,standard derivation of solid fraction with time,temporal distribution of the flow field,and particle residence time distribution are measured in the simulation,which are meaningful to better design and operate such systems in the future.

关键词： Discrete particle method Coarse-grain Maximizing iso-paraffins Full-loop Reaction-regeneration system

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Curcumin Interferes with TGF-β1-Induced Fibrosis in NRK-49F Cells by Reversing ADAMTS18 Gene Methylation

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Chinese Journal of Integrative Medicine 2024年第7期30卷 600-607页

作者： XU Ben ZHANG Jia-en ye Lin YUAN Chang-wei Department of Urology Peking University First Hospital and Institute of Urology Peking UniversityNational Urological Cancer Center

Objective: To explore the molecular mechanism by which curcumin affects renal interstitial fibrosis（RIF） progression by regulating ADAM metallopeptidase with thrombospondin type 1 motif 18（ADAMTS18） methylation. Methods: NRK-49F cells RIF model were induced with transforming growth factor β1（TGF-β1）. Effects of different concentrations of curcumin（0, 10, 20, and 30 μmol/L） on cell proliferation, cell cycle, cell apoptosis as well as cyclin D1 expression were analyzed by cell counting kit-8, flow cytometry and Western blot, respectively. ADAMTS18 methylation levels were determined by methylation-specific polymerase chain reaction. ADAMTS18, fibronectin（FN）, type Ⅰ collagen（Col-Ⅰ） and alpha-smooth muscle actin（α-SMA） mRNA and protein expressions were analyzed by real-time PCR（RT-PCR） and Western blot, respectively. Meanwhile, cells were treated with 50 mmol/L 5-aza-2'-deoxycytidine（5-aza-dC, demethylation agent） for 72 h. Effect of curcumin on extracellular matrix（ECM） deposition was evaluated by immunochemical staining and Western blot. NRK-49F cells were transfected with ADAMTS18 small interfering RNA and grouped into a normal control, ADAMTS18-knock-out（KO）, and ADAMTS18-KO+ 30 μmol/L curcumin groups, and whether curcumin can reverse the effect of ADAMTS18 knockdown on RIF was evaluated. Results: Compared with the control group, TGF-β1 significantly inhibited the proliferation of NRK-49F cells, blocked the G1/G0phase, promoted cell apoptosis and inhibited cyclin D1 expression（P<0.01）. Among the different concentrations of curcumin, 30 μmol/L curcumin significantly reversed these processes（P<0.01）. Immunochemical staining and Western blot results showed that curcumin significantly inhibited the deposition of FN, Col-Ⅰ and α-SMA（P<0.01）. Curcumin and 5-zaz-dC had synergistic effects, promoting ADAMTS18 expression, removing ADAMTS18 methylation, and reducing ECM deposition. ADAMTS18 knockdown promoted ECM accumulation, and curcumin reversed this process（P<0.01）. Conclusion: TGF-β1 induced fibrosis in NRK-49F cells.

关键词： renal fibrosis curcumin Chinese medicine ADAMTS18 methylation modification

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Metabolic basis of solute carrier transporters in treatment of type 2 diabetes mellitus

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Acta Pharmaceutica Sinica B 2024年第2期14卷 437-454页

作者： Jiamei Le Yilong Chen wei Yang Ligong Chen Jianping ye Shanghai Key Laboratory of Molecular Imaging Zhoupu HospitalShanghai University of Medicine and Health SciencesShanghai 201318China School of Health Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Metabolic Disease Research Center Zhengzhou Central Hospital Affiliated to Zhengzhou UniversityZhengzhou 450007China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China Research Center for Basic Medicine Academy of Medical SciencesZhengzhou UniversityZhengzhou 450052China

Solute carriers(SLCs) constitute the largest superfamily of membrane transporter proteins.These transporters, present in various SLC families, play a vital role in energy metabolism by facilitating the transport of diverse substances, including glucose, fatty acids, amino acids, nucleotides, and ions.They actively participate in the regulation of glucose metabolism at various steps, such as glucose uptake(e.g., SLC2A4/GLUT4), glucose reabsorption(e.g., SLC5A2/SGLT2), thermogenesis(e.g., SLC25A7/UCP-1), and ATP production(e.g., SLC25A4/ANT1 and SLC25A5/ANT2). The activities of these transporters contribute to the pathogenesis of type 2 diabetes mellitus(T2DM). Notably, SLC5A2 has emerged as a valid drug target for T2DM due to its role in renal glucose reabsorption, leading to groundbreaking advancements in diabetes drug discovery. Alongside SLC5A2, multiple families of SLC transporters involved in the regulation of glucose homeostasis hold potential applications for T2DM therapy. SLCs also impact drug metabolism of diabetic medicines through gene polymorphisms, such as rosiglitazone(SLCO1B1/OATP1B1) and metformin(SLC22A1-3/OCT1-3 and SLC47A1, 2/MATE1, 2). By consolidating insights into the biological activities and clinical relevance of SLC transporters in T2DM, this review offers a comprehensive update on their roles in controlling glucose metabolism as potential drug targets.

关键词： Solute carriers(SLCs) Energ ymetabolism ATP production Type 2 diabetes mellitus(T2DM) Glucose homeostasis Polymorphisms

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Tuning the surface electronic structure of noble metal aerogels to promote the electrocatalytic oxygen reduction

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Journal of Energy Chemistry 2024年第2期89卷 557-564,I0013页

作者： Hongxing Yuan wei Gao Xinhao Wan Jianqi ye Dan Wen State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072ShaanxiChina

The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion devices.Regulating the electronic structure of electrocatalysts by ligands has received particular attention in deriving valid ORR electrocatalysts.Here,the surface electronic structure of Ptbased noble metal aerogels(NMAs)was modulated by various organic ligands,among which the electron-withdrawing ligand of 4-methylphenylene effectively boosted the ORR electrocatalysis.Theoretical calculations suggested the smaller energy barrier for the transformation of O^(*) to OH^(*) and downshift the d-band center of Pt due to the interaction between 4-methylphenylene and the surface metals,thus enhancing the ORR intrinsic activity.Both Pt3Ni and Pt Pd aerogels with 4-methylphenylene decoration performed significant enhancement in ORR activity and durability in different media.Remarkably,the 4-methylphenylene modified Pt Pd aerogel exhibited the higher halfwave potential of 0.952 V and the mass activity of 10.2 times of commercial Pt/C.This work explained the effect of electronic structure on ORR electrocatalytic properties and would promote functionalized NMAs as efficient ORR electrocatalysts.

关键词： Noble metal aerogels Surface electronic structure ORR Electrocatalyst Organic ligands

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Ultralow friction PTFE/PEEK heterolayer:A new solid lubrication approach toward simplicity

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Friction 2024年第1期12卷 120-135页

作者： wei SUN Jiaxin ye Qingrui SONG Yi FENG Xiaojun LIU School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Institute of Tribology School of Mechanical EngineeringHefei University of TechnologyHefei 230009China

Tribological applications of polytetrafluoroethylene(PTFE)are often limited by technological complexity to overcome its poor wear resistance.Here,a PTFE/polyetheretherketone(PEEK)heterolayer(HL)was proposed and evaluated as a new solid lubrication solution.Pin-on-disk tribometry found the lowest friction coefficient(μ)of 0.031 and ultralow wear for the PEEK/HL under typical conditions.The friction coefficient of the HL surpasses those of the state-of-the-art polymeric coatings/composites by at least 200%,and approaches that of highly lubricated interfaces.Mechanistic investigations revealed multi-length physical and chemical heterogeneity of the HL that best facilitates a tribofilm with high subsurface stability and surface instability.The technological simplicity and robustness of the HL’s high lubricity make it a promising new type of solid lubrication toward greater reliability and longevity.

关键词： ultralow friction anti-wear polytetrafluoroethylene(PTFE) heterolayer(HL)

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Prediction of maximum upward displacement of shield tunnel linings during construction using particle swarm optimization-random forest algorithm

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 1-17页

作者： Xiaowei ye Xiaolong ZHANG Yanbo CHEN Yujun wei Yang DING MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou310058China Department of Civil Engineering Zhejiang UniversityHangzhou310058China Zhejiang Engineering Research Center of Intelligent Urban Infrastructure Hangzhou City UniversityHangzhou310015China

During construction,the shield linings of tunnels often face the problem of local or overall upward movement after leaving the shield tail in soft soil areas or during some large diameter shield projects.Differential floating will increase the initial stress on the segments and bolts which is harmful to the service performance of the tunnel.In this study we used a random forest(RF)algorithm combined particle swarm optimization(PSO)and 5-fold cross-validation(5-fold CV)to predict the maximum upward displacement of tunnel linings induced by shield tunnel excavation.The mechanism and factors causing upward movement of the tunnel lining are comprehensively summarized.Twelve input variables were selected according to results from analysis of influencing factors.The prediction performance of two models,PSO-RF and RF(default)were compared.The Gini value was obtained to represent the relative importance of the influencing factors to the upward displacement of linings.The PSO-RF model successfully predicted the maximum upward displacement of the tunnel linings with a low error(mean absolute error(MAE)=4.04 mm,root mean square error(RMSE)=5.67 mm)and high correlation(R^(2)=0.915).The thrust and depth of the tunnel were the most important factors in the prediction model influencing the upward displacement of the tunnel linings.

关键词： Random forest(RF) Particle swarm optimization(PSO) Upward displacement of lining Machine learning prediction Shieldtunneling construction

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Phosphine-catalyzed acyl-transfer of heteroaryl ketones for the construction of N-fused heterocycles

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Chinese Chemical Letters 2024年第3期35卷 252-256页

作者： Yu Zhang De-Rui Han Dan ye Hong Lu Hao wei Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710069China

An inexpensive phosphine catalyst was used effectively for a transition-metal-free acyl-transfer of N-containing heteroaryl ketones for the rapid synthesis of N-fused heterocycles.The key pre-aromatic spirocyclic intermediate initialized by the single electron transfer(SET)process of Togni's reagentⅡpromoted by the tertiary phosphine resulted in an intriguing and alternative tactic for the cleavage of C–C bonds.By using inexpensive tertiary phosphine as the catalyst,this skeleton-reorganizing approach of N-containing heteroaryl ketones allows a streamlined assembly of complex N-fused heterocycles with broad functional group tolerance.

关键词： Phosphine catalysis Acyl-transfer N-Fused heterocycles C–C bond activation Aromatization

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