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NUMERICAL AND EXPERIMENTAL STUDIES OF INFLUENCE OF THE CAUDAL FIN SHAPE ON THE PROPULSION PERFORMANCE OF A FLAPPING CAUDAL FIN

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Journal of Hydrodynamics 2011年第3期23卷 325-332页

作者： ZHANG Xi SU yu-min WANG zhao-li State Key Laboratory of Autonomous Underwater Vehicle Harbin Engineering University Harbin 150001 China

This article presents a comprehensive study of the effects of the caudal fin shape on the propulsion performance of a candal fin in harmonic heaving and pitching. A numerical simulation based on an unsteady panel method was carried out to analyze the hydrodynamic performance of flapping caudal fins of three shapes （the whale caudal fin with the largest projected area, the dolphin caudal fin with the median projected area, and the tuna caudal fin with the smallest projected area）. Then, a series of hydrodynamic experiments for three caudal fin shapes were performed. Both computational and experimental results indicate that the tuna caudal fin produces the highest efficiency. However the mean thrust coefficient of the tuna caudal fin is the smallest. It is found that although the mean thrust coefficient for the tuna caudal fin is not large, the input power of the tuna caudal fin is also quite small. So the tuna caudal fin achieves a high efficiency.

关键词： flapping caudal fin caudal fin shape numerical simulations hydrodynamic experiments hydrodynamic performance

Simplicity, symmetry, and beauty of atomic nuclei

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Frontiers of physics 2018年第6期13卷 1-2页

作者： Jie Meng Takaharu Otsuka yu-min zhao

Professor Akito Arima is an internationally renowned scientist, a most treasured and beloved colleague, friend and teacher to many nuclear physicists worldwide. Many colleagues have learned from him and enjoyed his be...

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NUMERICAL SIMULATION OF UNSTEADY TURBULENT FLOW INDUCED BY TWO-DIMENSIONAL ELEVATOR CAR AND COUNTER WEIGHT SYSTEM

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Journal of Hydrodynamics 2007年第6期19卷 720-725页

作者： SHI Li-qun LIU Ying-zheng JIN Si-yu CAO zhao-min Power Machinery Engineering lab Key Lab of Education Ministry of China School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China

A two-dimensional model of unsteady turbulent flow induced by high-speed elevator system was established in the present study. The research was focused on the instantaneous variation of the aerodynamic force on the car structure during traversing motion of the counter weight in the hoistway. A dynamic meshing method was employed to treat the multi-body motion system to avoid poor distortion of meshes. A comprehensive understanding of this significant aspect was obtained by varying the horizontal gap （δ =0.1m, 0.2m, and 0.3m） between the elevator car and the counter weight, and the moving speed （ U 0= 2m/s, 6m/s, and 10m/s） of the elevator system. A pulsed intensification of the aerodynamic force on the elevator car and subsequent appearance of large valley with negative aerodynamic force were clearly observed in the numerical results. In parameters studied （ δ =0.1m, U 0= 2m/s, 6m/s, 10m/s）, the peaked horizontal and vertical forces are respectively 7-11 and 4.3-5.65 times of that when the counter weight is far from the car. These results demonstrated the prominent influence of the traversing counter weight on aerodynamic force on the elevator car, which is of great significance to designers of high-speed elevator system.

关键词： high-speed elevator turbulent flow aerodynamic force Computational Fluid Dynamics (CFD)

Changes in source contributions to the oxidative potential of PM_(2.5)in urban Xiamen,China

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Journal of Environmental Sciences 2025年第3期149卷 342-357页

作者： Jia-min Li Si-min zhao Qi-yu Miao Shui-Ping Wu Jie Zhang James J.Schwab Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies Xiamen UniversityXiamen 361102China Center for Marine Environmental Chemistry and Toxicology College of Environment and EcologyXiamen UniversityXiamen 361102China Atmospheric Sciences Research Center University at AlbanySUNYAlbany 12226USA

The toxicity of PM_(2.5)does not necessarily change synchronously with its mass *** this study,the chemical composition(carbonaceous species,water-soluble ions,and metals)and oxidative potential(dithiothreitol assay,DTT)of PM_(2.5)were investigated in 2017/2018 and 2022 in Xiamen,*** decrease rate of volume-normalized DTT(DTTv)(38%)was lower than that of PM_(2.5)(55%)between the two sampling ***,the mass-normalized DTT(DTTm)increased by 44%.Clear seasonal patterns with higher levels in winter were found for PM_(2.5),most chemical constituents and DTTv but not for *** large decrease in DTT activity(84%−92%)after the addition of EDTA suggested that watersoluble metals were the main contributors to DTT in *** increased gap between the reconstructed and measured DTTv and the stronger correlations between the reconstructed/measured DTT ratio and carbonaceous species in 2022were *** decrease rates of the hazard index(32.5%)and lifetime cancer risk(9.1%)differed from those of PM_(2.5)and DTTv due to their different main *** PMF-MLR model showed that the contributions(nmol/(min·m^(3)))of vehicle emission,coal+biomass burning,ship emission and secondary aerosol to DTTv in 2022 decreased by 63.0%,65.2%,66.5%,and 22.2%,respectively,compared to those in 2017/2018,which was consistent with the emission reduction of vehicle exhaust and coal consumption,the adoption of low-sulfur fuel oil used on board ships and the reduced production of ***,the contributions of dust+sea salt and industrial emission increased.

关键词： Chemical composition Oxidative potential Interannual change PMF-MLR Source apportionment

Manybody system with random interaction

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Manybody system with random interaction

IL-17A mediates inflammation-related retinal pigment epithelial cells injury via ERK signaling pathway

The 6th China-Nuclear Physics Symposium

作者： yu-min zhao

In recent years my collaborators and I have been studying regularities of many-body systems in the presence of random interactions. This topic was ignited by numerical observations by Johnson, Bertsch and Dean that spin zero ground state dominance (0 g.s.) can be obtained by using random interactions. Many authors

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 15-27页

作者： Hui-min Zhong Bing-Qiao Shen yu-Hong Chen Xiao-Huan zhao Xiao-Xu Huang min-Wen Zhou Xiao-Dong Sun Department of Ophthalmology Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong UniversitySchool of MedicineShanghai 200080China National Clinical Research Center for Ophthalmic Diseases Shanghai 200080China National Clinical Research Center for Eye Diseases Shanghai 200080China Shanghai Key Laboratory of Fundus Diseases Shanghai 200080China Shanghai Engineering Center for Visual Science and Photomedicine Shanghai 200080China

AIM:To investigate whether interleukin-17A(IL-17A)gets involved in the mechanisms of inflammation-related retinal pigment epithelium(RPE)cells injury and its significance in age-related macular degeneration(AMD).MRTHODS:A sodium iodate(NaIO3)mouse model as well as IL-17A-/-mice were *** effects of inflammatory cytokines in RPE cells and retinal microglia before and after NaIO3 modeling in vivo and in vitro,were investigated using immunofluorescence,immunoprotein blotting,and quantitative real-time fluorescence polymerase chain reaction(qRT-PCR),*** using recombinant IL-17A protein(rIL-17A)or IL-17A neutralizing antibody(IL-17A NAb)were used to observe the subsequent differences in fundus,fundus photography and optical coherence tomography(OCT),cell viability,and expression of oxidative stress-related markers before and after modeling,and to screen for key signaling ***:In the scenario of NaIO3 stimulation,RPE cells obviously tended to *** proliferation and activation of retinal microglia was confirmed in NaIO3-stimulated mice,whereas such effects induced by NaIO3 were significantly ameliorated with IL-17A NAb intervention or in IL-17A-/-*** addition,IL-17A promoted the proliferation and activation of microglia as well as oxidative damage and the secretion of inflammatory cytokines alongside NaIO3-induced damage in RPE cells in vivo and ex ***,the extracellular signalregulated kinase(ERK)signaling pathway was shown to be participated in the regulation of NaIO3-induced RPE cells injury mediated by IL-17A in vivo and ex vivo,as IL-17A induced inflammatory cytokines release in the NaIO3 model was alleviated after blocking the ERK ***:IL-17A probably promotes the NaIO3-induced RPE cells injury through exacerbating inflammation in terms of retinal microglia activation and inflammatory cytokines release via ERK signaling *** of IL-17A may be a new potential ta

关键词： age-related macular degeneration retinal pigment epithelium NaIO3 microglia IL-17A

Petrogenesis of late Cretaceous high Ba-Sr granodiorites,SE Lhasa block,China:implications for the reworking of juvenile crust and continental growth

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Acta Geochimica 2025年第1期44卷 86-111页

作者： Li-Hang Lin Ren-Zhi Zhu Shao-Cong Lai Jiang-Feng Qin yu Zhu Shao-Wei zhao min Liu State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China ministry of Education Key Laboratory of Western China’s mineral Resources and Geological Engineering School of Earth Science and ResourcesChang’an UniversityXi’an 710054China

The high Ba-Sr rocks can provide significant clues about the evolution of the continent lithosphere,but their petrogenesis remains *** the Late Cretaceous high Ba–Sr granodiorites in the SE Lhasa Block could potentially provide valuable insights into the continent evolution of the Qinghai-Tibet *** U–Pb ages suggest that the granodiorites were emplaced at 87.32±0.43 ***,the high Ba–Sr granodiorites are characterized by elevated K_(2)O+Na_(2)O contents(8.18-8.73 wt%)and K_(2)O/Na_(2)O ratios(0.99-1.25,mostly>1),and belong to high-K calc-alkaline to shoshonitic *** Yonglaga granodiorites show notably high Sr(653-783 ppm)and Ba(1346-1531 ppm)contents,plus high Sr/Y(30.92-38.18)and(La/Yb)_(N)(27.7-34.7)ratios,but low Y(20.0-22.8 ppm)and Yb(1.92-2.19 ppm)contents with absence of negative Eu anomalies(δEu=0.83-0.88),all similar to typical high Ba–Sr *** variable zirconεHf(t)values of-4.58 to+12.97,elevated initial^(87)Sr/^(86)Sr isotopic ratios of 0.707254 to 0.707322 and lowεNd(t)values of-2.8 to-3.6 with decoupling from the Hf system suggest that a metasomatized mantle source included significant recycled ancient *** occurrence of such high Ba–Sr intrusions indicates previous contributions of metasomatized mantle-derived juvenile material to the continents,which imply the growth of continental crust during the Late Cretaceous in the SE *** with regional data,we infer that the underplated mafic magma provides a significant amount of heat,which leads to partial melting of the juvenile *** melting of the metasomatized mantle could produce a juvenile mafic lower crust,from which the high Ba–Sr granitoids were derived from reworking of previous mafic crust during the Late Cretaceous(ca.100-80 Ma)in the SE Lhasa.

关键词： Late Cretaceous High Ba-Sr granodiorites SE Lhasa Growth of continental crust Juvenile crust

Conjunctival microbiota variations in a subset of middleaged and elderly individuals from Beijing,China

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 237-243页

作者： Tian-Yao zhao yu-Chen Wang Ying-Juan Sun Jun-yue Wang Xiao-Dan Jiang Xue-min Li Ai-Hua Deng Department of Ophthalmology Peking University Third HospitalBeijing Key Laboratory of Restoration of Damaged Ocular NerveBeijing 100191China Fangshan Hospital Beijing University of Chinese Medicine Beijing 102400China CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Animal Nutrition and Feeding Ministry of Agriculture and Rural Affairs Feed Industry CentreAgricultural UniversityBeijing 100193China

AIM:To isolate and identify the conjunctival microbiota of cataract patients and analyze the associated influencing ***:This study recruited 216 participants(216 eyes)from April 2022 to July *** the condition of no antibiotic use prior to cataract surgery,sterile swabs were used to collect samples from the lower conjunctival *** cultures were then conducted,followed by species identification through 16S rDNA gene *** factors associated with positive or negative bacterial isolation rates were analyzed,including age,gender,meibomian gland dysfunction(MGD),history of hypertension,history of diabetes,history of cancer,history of infectious diseases and the habit of wearing ***:Among the 216 eyes,78 eyes yielded isolates,with an isolation rate of 36.11%,detecting a total of 122 ***-positive rods accounted for 49.18%(60 strains),gram-positive cocci accounted for 45.08%(55 strains),gram-negative bacteria accounted for 4.92%(6 strains),and fungi accounted for 0.82%(1 strain).This study found that the most abundant genera in the conjunctival sac were Corynebacterium(42.62%),Staphylococcus(31.15%),Micrococcus(9.84%),Acinetobacter(4.10%),and Bacillus(3.28%).Furthermore,age(P=0.006),gender(P=0.039),diabetes(P=0.003),history of infectious diseases(P=0.02),and duration of mask replacement(P<0.001)were important factors influencing the positive bacterial culture of the conjunctival *** hypertensive patients exhibited a higher isolation rate of conjunctival bacteria,it did not reach statistical significance,and the history of cancer did not affect the isolation rate of the conjunctival microbial community in cataract patients before ***:Potential changes are observed in the conjunctival microbiota among a sample of middleaged and elderly individuals from Beijing,***,an increased isolation rate of Corynebacterium and Micrococcus is detected,suggesting a possible change in the mic

关键词： conjunctival microbiota 16S rDNA middle-aged and elderly population mask cataract surgery

COMPrompter: reconceptualized segment anything model with multiprompt network for camouflaged object detection

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Science China(Information Sciences) 2025年第1期68卷 189-203页

作者： Xiaoqin ZHANG Zhenni yu Li zhao Deng-Ping FAN Guobao XIAO Zhejiang Province Key Laboratory of Intelligent Informatics for Safety and Emergency Wenzhou University Nankai International Advanced Research Institute (SHENZHEN FUTIAN) College of Computer Science Nankai University School of Computer Science and Technology Tongji University

We rethink the segment anything model(SAM) and propose a novel multiprompt network called COMPrompter for camouflaged object detection(COD). SAM has zero-shot generalization ability beyond other models and can provide an ideal framework for COD. Our network aims to enhance the single prompt strategy in SAM to a multiprompt strategy. To achieve this, we propose an edge gradient extraction module, which generates a mask containing gradient information regarding the boundaries of camouflaged objects. This gradient mask is then used as a novel boundary prompt, enhancing the segmentation process. Thereafter, we design a box-boundary mutual guidance module, which fosters more precise and comprehensive feature extraction via mutual guidance between a boundary prompt and a box prompt. This collaboration enhances the model's ability to accurately detect camouflaged objects. Moreover, we employ the discrete wavelet transform to extract high-frequency features from image embeddings. The high-frequency features serve as a supplementary component to the multiprompt ***, our COMPrompter guides the network to achieve enhanced segmentation results, thereby advancing the development of SAM in terms of COD. Experimental results across COD benchmarks demonstrate that COMPrompter achieves a cutting-edge performance, surpassing the current leading model by an average positive metric of 2.2% in COD10K. In the specific application of COD, the experimental results in polyp segmentation show that our model is superior to top-tier methods as well. The code will be made available at https://***/guobaoxiao/COMPrompter.

关键词： segment anything model camouflaged object detection boundary prompt

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