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A Numerical Calculation Algorithm of the Inclination Function Based on the Representation of SO(3) Group

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 137-148页

作者： yu-xiao Wei Wen-lin Tang Department of Geophysics School of Geology Engineering and GeomaticsChang’An UniversityXi’an710064China Key Laboratory of Electronics and Information Technology for Space Systems National Space Science CenterChinese Academy of SciencesBeijing100190China

In the determination of the Earth gravity field in satellite geodesy, the inclination functions represent the projection of data observed along the orbital plane of a satellite orbit into the sphere in the terrestial reference frame. The inclination functions in this work is studied from a group theoretical perspective. The inclination functions are proved to generate a representation of the SO(3) group. An orthogonal relation of the inclination functions is derived and some recurrence relations for the inclination functions are given, based on which an algorithm to calculate the inclination functions is proposed.

关键词： SO(3)group inclination function satellite geodesy representation of SO(3)

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Quantifying trapping stability of optical tweezers with an external flow

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Photonics Research 2024年第08期12卷 1741-1749页

作者： FENG XU YARONG yu YANG LIU YAO CHANG WENXIANG JIAO lin WANG HOPUI HO BEI WU fei XU YANQING LU yuANJIE PANG GUANGHUI WANG College of Engineering and Applied Sciences Nanjing University Key Laboratory of Intelligent Optical Sensing and Integration of the Ministry of Education Nanjing University School of Optical and Electronic Information Wuhan National Laboratory of Optoelectronics Huazhong University of Science and Technology Department of Biomedical Engineering The Chinese University of Hong Kong

Optical tweezers(OTs) can immobilize and manipulate objects with sizes that span between nano-and micrometer scales. The manipulating ability of OTs is traditionally characterized by stability factor(S), which can only indicate an empirical “hit-or-miss” process. Additionally, the current quantitative models for trapping stability rarely consider the influence of external flow. In this paper, a comprehensive analysis to quantify the optical trapping stability in a perturbed asymmetric potential well is presented from the perspective of statistics, especially for weak trapping scenarios. Our analytical formulation takes experimentally measurable parameters including particle size, optical power, and spot width as inputs and precisely outputs a statistically relevant mean trapping time. Importantly, this formulation takes into account general and realistic cases including fluidic flow velocity and other perturbations. To verify the model, a back-focal-plane-interferometer-monitored trapping experiment in a flow is set up and the statistical characteristics of trapping time demonstrate good agreement with theoretical predictions. In total, the model quantitatively reveals the effects of external disturbance on trapping time, which will find applications where optical trapping stability is challenged by external perturbations in weak trapping conditions.

关键词： Finite-difference time-domain method Gaussian beams Numerical simulation Optical trapping Optical tweezers Systems design

Effect of rare earth on primary carbides in H13 die steel and their addition method:a review

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Journal of Iron and Steel Research International 2024年第3期31卷 531-551页

作者： Jing-feng Wang lin-zhu Wang Chao-yi Chen Xiang Wang fei Zhao School of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina Zhengzhou Railway Vocational and Technical College Zhengzhou 450000HenanChina Guizhou Provincial University Key Laboratory of High Performance Battery Materials Guizhou UniversityGuiyang 550025GuizhouChina Shougang Guiyang Special Steel Co. Guiyang 550005GuizhouChina

Larger-sized primary carbides lead to stress concentration during the application of H13 hot-work die steel,resulting in microcracks and fatigue *** earth was usually added to modify the carbides and *** existing literature is reviewed on the effect of rare earth on primary carbides in H13 steel.A comprehensive review on the effect of rare earth on the characteristics of primary carbides,i.e.,number,size,morphology,and thermal stability in H13 steel,was *** precipitation mechanism and nucleation of primary carbides with rare earth were *** position and form of rare earth in steel and their effects on alloying elements segregation were *** addition techniques of rare earth in H13 steel were compared,and the prospects for other uncommon rare earth and emerging technology were *** on the current references,it can be known that adding rare earth facilitated refined and dispersed primary *** size of primary carbides would be reduced,and their morphology would be improved because the rare earth inclusions formed in H13 steel can act as nucleation cores forγ-Fe orδ-Fe,refining the dendritic ***,the number of primary carbides at grain boundaries would be significantly ***,rare earth had little impact on thermal *** nucleation of primary carbides tended to be inhibited due to the modification of inclusions by rare earth which were likely to be nucleation cores for primary *** earth had been reported to affect the mechanism and process of primary carbide ***,the addition of rare earth can inhibit the segregation of alloying elements and carbon diffusion by ***,laboratory experiments and theoretical calcu-lations need to be conducted to study the states and evolution of rare earth steels.

关键词： Rare earth H13 die steel Primary carbide Nucleation Dendritic structure

Investigation on the influence of vortex generator on particle resuspension

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Particuology 2024年第3期86卷 126-136页

作者： Dongchi yu Jun-Li lin Jin-Han Xie ASML 80W Tasman DrSan Jose95134CaliforniaUSA Department of Mechanics and Engineering Science at College of Engineering and State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100081China

The vortex generator(VG)and its well-known effect in flow optimization are widely studied and employed across different engineering ***,while the same working principles of VG may be well suited for the applications on surface-cleaning technologies,such promising potential is hardly,if any,explored in the published ***,in the present study,the influence on flow-induced particle resuspension brought by a rectangular vG in a channel flow is investigated with the help of highfidelity computational fluid dynamics *** increases of particle removal forces and resuspension rates are discovered in long,strip-like regions with reduced boundary-layer thickness resulted from the vG-induced vortices,and the enhancement effect is especially significant for configurations with the VG installed at a greater angle of *** is also shown that while the resuspension enhancements on the lower and the upper surfaces of the channel exhibit distinct statistical characteristics,having a VG in the channel improves the overall particle-removing capability of the channel flow by introducing higher surface-averaged removal forces and particle resuspension *** but not least,the increase of resuspension rate is especially significant for the smaller,micron-scale particles which are otherwise hardly disturbed by a VG-less channel flow,and such resuspension-enhancement effectgenerally subsides with increasing particle size.

关键词： Particle resuspension Vortexgenerator CFD Surface cleaning

Comprehensive Understanding of Immune Cells in The Pathogenesis of Non-alcoholic Fatty Liver Disease

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生物化学与生物物理进展 2024年第9期51卷 2082-2100页

作者： OUYANG fei-Fan RASHEED Madiha LI Bo DENG yu-lin Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyZhuhai 519088China Beijing Key Laboratory for Separation and Analysis in Biomedicine and Pharmaceuticals School of Life ScienceBeijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China

Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease,defined by several phases,ranging from benign fat accumulation to non-alcoholic steatohepatitis(NASH),which can lead to liver cancer and *** NAFLD is a disease of disordered metabolism,it also involves several immune cell-mediated inflammatory processes,either promoting and/or suppressing hepatocyte inflammation through the secretion of pro-inflammatory and/or anti-inflammatory factors to influence the NAFLD ***,the underlying disease mechanism and the role of immune cells in NAFLD are still under investigation,leaving many open-ended *** this review,we presented the recent concepts about the interplay of immune cells in the onset and pathogenesis of *** also highlighted the specific non-immune cells exhibiting immunological properties of therapeutic significance in *** hope that this review will help guide the development of future NAFLD therapeutics.

关键词： non-alcoholic fatty liver disease metabolically associated fatty liver disease(MAFLD) T cells myeloid cells mesenchymal stem cells

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Emerging role of lncRNAs as mechanical signaling molecules in mechanotransduction and their association with Hippo-YAP signaling:a review

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 280-292页

作者： Siyi lin Xinyu HE Ying WANG yu CHEN Aifu lin College of Medicine Zhejiang UniversityHangzhou 310058China College of Life Sciences Zhejiang UniversityHangzhou 310058China Cancer Center Zhejiang UniversityHangzhou 310058China Key Laboratory for Cell and Gene Engineering of Zhejiang Province Hangzhou 310058China International School of Medicine International Institutes of Medicinethe Fourth Affiliated Hospital of Zhejiang University School of MedicineYiwu 322000China Key Laboratory of Cancer Prevention and Intervention China National Ministry of EducationHangzhou 310058China Future Health Laboratory Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100China

Cells within tissues are subject to various mechanical forces,including hydrostatic pressure,shear stress,compression,and *** mechanical stimuli can be converted into biochemical signals through mechanoreceptors or cytoskeleton-dependent response processes,shaping the microenvironment and maintaining cellular physiological *** studies have demonstrated the roles of Yes-associated protein(YAP)and its homolog transcriptional coactivator with PDZ-binding motif(TAZ)as mechanotransducers,exerting dynamic influence on cellular phenotypes including differentiation and disease *** regulatory function entails the involvement of the cytoskeleton,nucleoskeleton,integrin,focal adhesions(FAs),and the integration of multiple signaling pathways,including extracellular signal-regulated kinase(ERK),wingless/integrated(WNT),and Hippo ***,emerging evidence substantiates the implication of long non-coding RNAs(lncRNAs)as mechanosensitive molecules in cellular *** this review,we discuss the mechanisms through which YAP/TAZ and lncRNAs serve as effectors in responding to mechanical ***,we summarize and elaborate on the crucial signal molecules involved in mechanotransduction.

关键词： YAP/TAZ Long non-coding RNA(lncRNA) Mechanotransduction F-actin

Scorpiones,Scolopendra and Gekko Inhibit Lung Cancer Growth and Metastasis by Ameliorating Hypoxic Tumor Microenvironment via PI3K/AKT/mTOR/HIF-1αSignaling Pathway

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Chinese Journal of Integrative Medicine 2024年第9期30卷 799-808页

作者： MAO Qi-yuan WANG Xue-qian lin fei yu Ming-wei FAN Hui-tin' ZHENG Qi LIU Lan-chun ZHANG Chu-chu LI Dao-rui lin Hong-sheng Department of Oncology Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China Department of Oncology Beijing Hospital of Traditional Chinese MedicineCapital Medical UniversityBeijing100010China Department of Cardiology Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China Institute of Traditional Chinese Medicine Information China Academy of Chinese Medical SciencesBeijing100700China

Objective:To investigate whether Buthus martensii karsch(Scorpiones),Scolopendra subspinipes mutilans ***(Scolopendra)and Gekko gecko linnaeus(Gekko)could ameliorate the hypoxic tumor microenvironment and inhibit lung cancer growth and metastasis by regulating phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin/hypoxia-inducible factor-1α(PI3K/AKT/mTOR/HIF-1α)signaling ***:Male C57BL/6J mice were inoculated with luciferase labeled LL/2-luc-M38 cell suspension to develop lung cancer models,with rapamycin and cyclophosphamide as positive *** methyl cellulose solutions of Scorpiones,Scolopendra and Gekko were administered intragastrically as 0.33,0.33,and 0.83 g/kg,respectively once daily for 21 *** expression were detected every 7 days after inoculation,and tumor growth curves were *** was performed to determine CD31 and HIF-1αexpressions in tumor tissue and microvessel density(MVD)was *** blot was performed to detect the expression of PI3K/AKT/mTOR/HIF-1αsignaling pathway-related ***-linked immunosorbent assay was performed to detect serum basic fibroblast growth factor(bFGF),transforming growth factor-β1(TGF-β1)and vascular endothelial growth factor(VEGF)in ***:Scorpiones,Scolopendra and Gekko prolonged the survival time and inhibited lung cancer metastasis and expression of HIF-1α(all Pling pathway.

关键词： Scorpiones Scolopendra Gekko dredging collaterals and activating blood Chinese medicine of worms lung cancer hypoxic tumor microenvironment phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin/hypoxia-inducible factor-1α signaling pathway

High-precision X-ray polarimeter based on channel-cut crystals

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Nuclear Science and Techniques 2024年第3期35卷 30-39页

作者： Shang-yu Si Zhong-Liang Li Wen-Hong Jia Lian Xue Hong-Xin Luo Jian-Cai Xu Bai-fei Shen lin-Gang Zhang Liang-Liang Ji yu-Xin Leng Ren-Zhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China

We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was *** result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet ***,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.

关键词： X-ray polarimeter Vacuum birefringence Synchrotron radiation Channel-cut crystal

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Low-Brightness Object Recognition Based on Deep Learning

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Computers, Materials & Continua 2024年第5期79卷 1757-1773页

作者： Shu-Yin Chiang Ting-yu lin Department of Information and Telecommunications Engineering Ming Chuan UniversityTaoyuan City333Taiwan

This research focuses on addressing the challenges associated with image detection in low-light environments,particularly by applying artificial intelligence techniques to machine vision and object recognition *** primary goal is to tackle issues related to recognizing objects with low brightness *** this study,the Intel RealSense Lidar Camera L515 is used to simultaneously capture color information and 16-bit depth information *** detection scenarios are categorized into normal brightness and low brightness *** the system determines a normal brightness environment,normal brightness images are recognized using deep learning *** low-brightness situations,three methods are proposed for *** first method is the SegmentationwithDepth image(SD)methodwhich involves segmenting the depth image,creating amask from the segmented depth image,mapping the obtained mask onto the true color(RGB)image to obtain a backgroundreduced RGB image,and recognizing the segmented *** second method is theHDVmethod(hue,depth,value)which combines RGB images converted to HSV images(hue,saturation,value)with depth images D to form HDV images for *** third method is the HSD(hue,saturation,depth)method which similarly combines RGB images converted to HSV images with depth images D to form HSD images for *** experimental results,in normal brightness environments,the average recognition rate obtained using image recognition methods is 91%.For low-brightness environments,using the SD method with original images for training and segmented images for recognition achieves an average recognition rate of over 82%.TheHDVmethod achieves an average recognition rate of over 70%,while the HSD method achieves an average recognition rate of over 84%.The HSD method allows for a quick and convenient low-light object recognition *** research outcome can be applied to nighttime surveillance systems or nighttime road safety systems

关键词： Low-brightness depth image image segmentation image recognition HDV HSD