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A color image encryption scheme based on a 2D coupled chaotic system and diagonal scrambling algorithm

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Chinese Physics B 2024年第7期33卷 233-243页

作者：苏静明方士辉洪炎温言 Anhui Mining Machinery and Electrical Equipment Coordination Innovation Center Anhui University of Science and TechnologyHuainan 232001China School of Computer Science and Information Engineering Hefei University of TechnologyHefei 230009China

A novel color image encryption scheme is developed to enhance the security of encryption without increasing the complexity. Firstly, the plain color image is decomposed into three grayscale plain images, which are converted into the frequency domain coefficient matrices(FDCM) with discrete cosine transform(DCT) operation. After that, a twodimensional(2D) coupled chaotic system is developed and used to generate one group of embedded matrices and another group of encryption matrices, respectively. The embedded matrices are integrated with the FDCM to fulfill the frequency domain encryption, and then the inverse DCT processing is implemented to recover the spatial domain signal. Eventually,under the function of the encryption matrices and the proposed diagonal scrambling algorithm, the final color ciphertext is obtained. The experimental results show that the proposed method can not only ensure efficient encryption but also satisfy various sizes of image encryption. Besides, it has better performance than other similar techniques in statistical feature analysis, such as key space, key sensitivity, anti-differential attack, information entropy, noise attack, etc.

关键词： color image encryption discrete cosine transform two-dimensional(2D)coupled chaotic system diagonal scrambling

Resilient performance of self-centering hybrid rocking walls with curved interface under pseudo-static loading

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 65-85页

作者： su Xing yan Shi sun Xianglei Wang Tao School of Civil Engineering Shenyang Jianzhu UniversityShenyang 110168China PetroChina East China Design Institute Co. Ltd.Qingdao 266000China Qingdao Country Garden Bolin Real Estate Co. Ltd.Qingdao 266100China

Frame and rocking wall(FRW)structures have excellent resilient performance during ***,the concrete at interfacial corners of rocking walls(RWs)is easily crushed due to local extreme compression during the rocking *** innovative RW with a curved interface is proposed to prevent interfacial corners from producing local damage,enhancing its earthquake resilient performance(ERP).The precast wall panel with a curved interface is assembled into an integral self-centering hybrid rocking wall(SCRW)by two post-tensioned unbonded prestressed ***,two ordinary energy dissipation steel rebars and two shear reinforcements are arranged to increase the energy dissipation capacity and lateral *** SCRW specimens and one monolithic reinforced concrete(RC)shear wall(SW)were tested under pseudo-static loading to compare the ERPs of the proposed SCRW and the SW,focusing on studying the effect of the curved interface on the *** key resilient performance of rocking effects,failure modes,and hysteretic properties of the SCRW were *** results show that nonlinear deformations of the SCRW are concentrated along the interface between the SCRW and the foundation,avoiding damage within the *** restoring force provided by the prestressed tendons can effectively realize self-centering capacity with small residual deformation,and the resilient performance of the SCRW is better than that of monolithic *** addition,the curved interface of the SCRW makes the rocking center change and move inward,partially relieving the stress concentration and crush of *** rocking range of the rocking center is about 41.4%of the width of the SCRW.

关键词： self-centering hybrid rocking wall(SCRW) monolithic shear wall(SW) earthquake resilient performance(ERP) curved interface rocking center

Recent progress in diagnostic imaging and therapeutics of osteosarcoma based on multifunctional nanoparticles

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Science China Chemistry 2024年第9期67卷 2864-2889页

作者： Xueke yan Danmin Lin Dingyuan yan Dong Wang Huifang su Department of Orthopaedic surgery The First Affiliated Hospital of Zhengzhou University Center for AIE Research College of Materials Science and Engineering Shenzhen University

Osteosarcoma is one of the most common primary bone malignancies, mainly occurring in children and adolescents. Traditional diagnosis imaging methods for osteosarcoma contain X-ray, computed tomography and magnetic resonance imaging, and traditional therapy protocols are surgical resection and chemotherapy. However, these strategies are complicated and *** imaging methods, despite their maturity, have drawbacks that prevent them from showing more details. What is more, the prognosis for patients with osteosarcoma remains unsatisfactory due to side effects of chemotherapy, as well as incomplete surgical removal of the tumor. To compensate for the shortcomings of traditional imaging and treatment strategies for osteosarcoma, various types of nanoparticles have been designed and synthesized to selectively target osteosarcoma cells without toxic side effects on healthy organs. At the same time, these nanoparticle-based technologies can integrate the imaging and treatment of osteosarcoma. This review summarizes the application of nanotechnology in the imaging and treatment of osteosarcoma in recent years, and finally discusses the challenges and development prospects, aiming to provide ideas for future research.

关键词： osteosarcoma nanotechnology imaging diagnosis therapy

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Cosmological Constraints on Neutrino Masses in Light of JWST Red and Massive Candidate Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 7-12页

作者： Jian-Qi Liu Zhi-Qi Huang yan su School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-hong Kong-Macao Greater Bay Area Zhuhai 519082China

The overabundance of the red and massive candidate galaxies observed by the James Webb Space Telescope(JWST)implies efficient structure formation or large star formation efficiency at high redshift z~*** the scenario of a low or moderate star formation efficiency,because massive neutrinos tend to suppress the growth of structure of the universe,the JWST observation tightens the upper bound of the neutrino *** A cold dark matter cosmology and a star formation efficiency∈[0.05,0.3](flat prior),we perform joint analyses of Planck+JWST and Planck+BAO+JWST,and obtain improved constraints∑m_(ν)sumptions,the inverted mass ordering,which implies ∑m_(ν)≥0.1 eV,is excluded by Planck+BAO+JWST at 92.7% confidence level.

关键词： (cosmology:)cosmological parameters galaxies:abundances galaxies:formation neutrinos

Experimental and numerical investigations on acoustic damping of monoclinic crystalline wideband sound absorbing structures

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Journal of Central South University 2024年第6期31卷 1931-1944页

作者： XIE su-chao HE Lei yan hong-yu ZHANG Feng-yi HE Guan-di WANG Jia-cheng Key Laboratory of Traffic Safety on Track Ministry of EducationSchool of Traffic&Transportation EngineeringCentral South UniversityChangsha 410075China Joint International Research Laboratory of Key Technology for Rail Traffic Safety Changsha 410075China National&Local Joint Engineering Research Center of Safety Technology for Rail Vehicle Changsha 410075China

In order to overcome the limitations of traditional microperforated plate with narrow sound absorption bandwidth and a single structure,two multi-cavity composite sound-absorbing materials were designed based on the shape of monoclinic crystals:uniaxial oblique structure(UOS)and biaxial oblique structure(BOS).Through finite element simulation and experimental research,the theoretical models of UOS and BOS were verified,and their sound absorption mechanisms were *** the same time,the influence of multi-cavity composites on sound absorption performance was analyzed based on the theoretical model,and the influence of structural parameters on sound absorption performance was *** research results show that,in the range of 100-2000 Hz,UOS has three sound absorption peaks and BOS has five sound absorption *** frequency range of the half-absorption bandwidth(α>0.5)of UOS and BOS increases by 242% and 229%,*** with traditional microperforated sound-absorbing structures,the series and parallel hybrid methods significantly increase the sound-absorbing bandwidth of the sound-absorbing *** research has guiding significance for noise control and has broad application prospects in the fields of transportation,construction,and mechanical design.

关键词： monoclinic crystal microperforated plate acoustic metamaterials inclined cavity sound absorption

An automatic Q-factor matching method for eliminating 77%of the ZRO of a MEMS vibratory gyroscope in rate mode

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Microsystems & Nanoengineering 2024年第3期10卷 35-48页

作者： Jingbo Ren Tong Zhou Yi Zhou Yixuan Li yan su School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210000China

Mismatching quality factors(Q-factors)is one of the main factors causing zero-rate output(ZRO)in degenerate(DE)Micro-Electro-Mechanical Systems(MEMS)vibratory *** eliminate the ZRO of the DE MEMS gyroscope,this study introduces a method for real-time identification and automatic matching of Q-factors in rate *** leveraging the vibration characteristics of the DE MEMS vibratory gyroscope in rate mode,dedicated online test methods are designed to determine the Q-factors for both the drive and sense modes,enabling online identification of the Q-factor ***,an automatic Q-factor matching system is designed utilizing the mechanical-thermal dissipation mechanism of the resistive *** effectiveness of this proposed method is validated through simulations and experiments conducted on a MEMS disk resonator gyroscope(DRG).The results show a measurement error within 4%for Q-factor identification,and automatic Q-factor matching effectively reduces the ZRO by 77%.Employing this automatic Q-factor matching method successfully reduces the ZRO that is caused by the mismatching of Q-factors in the MEMS DRG from 0.11°/s to 0.025°/s and improves the bias instability(BI)from 0.40°/s to 0.19°/s.

关键词： matching mode method

Lipid nanovehicles overcome barriers to systemic RNA delivery: Lipid components, fabrication methods, and rational design

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Acta Pharmaceutica Sinica B 2024年第2期14卷 579-601页

作者： Jing yan Hao Zhang Guangfeng Li Jiacan su yan Wei Can Xu Institute of Translational Medicine Shanghai UniversityShanghai 200444China Institute of Medicine Shanghai UniversityShanghai 200444China Department of Orthopedics Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China Department of Orthopedics Shanghai Zhongye HospitalShanghai 200941China Organoid Research Center Shanghai UniversityShanghai 200444China Department of Gastroenterology Changhai HospitalShanghai 200433China

Lipid nanovehicles are currently the most advanced vehicles used for RNA delivery,as demonstrated by the approval of patisiran for amyloidosis therapy in *** illuminate the unique superiority of lipid nanovehicles in RNA delivery,in this review,we first introduce various RNA therapeutics,describe systemic delivery barriers,and explain the lipid components and methods used for lipid nanovehicle ***,we emphasize crucial advances in lipid nanovehicle design for overcoming barriers to systemic RNA ***,the current status and challenges of lipid nanovehicle-based RNA therapeutics in clinical applications are also *** objective is to provide a comprehensive overview showing how to utilize lipid nanovehicles to overcome multiple barriers to systemic RNA delivery,inspiring the development of more high-performance RNA lipid nanovesicles in the future.

关键词： Lipid nanovehicles RNAtherapeutics Barriers to systemicRNA delivery Lipid components Fabricationmethods Lipid nanovehicledesign Extrahepatictissue targeting Organ tropism

Application and Comparison of Two SGS Models in Large Eddy Simulation of FreeTurbulent Jet Flow

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Communications in Nonlinear Science and Numerical Simulation 1999年第1期4卷 12-19页

作者： hong yan and Mingde su (Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China) Department of Engineering Mechanics Tsinghua University Beijing 100084 China

Large eddy simulations of spatially evolved turbulent round jets were presented. The two SGS models called the standard Smagorinsky’s eddy viscosity model and the non-eddy viscosity stimulated small scale(SSS) model developed by Shah & Ferziger were applied. The Reynolds number of the flow was taken as 10000 based on the orifice diameter and the axial velocity in the orifice. The comparison between these two models showed that the standard Smagorinsky’s viscosity model with Smagorinsky’s constant of 0.1 underestimated the turbulent intensity, while the SSS model showed a better agreement with the experiment. Also the SSS model was used to investigate the development of vortex. The convective boundary condition at the outflow boundary was adopted to ensure less effect of noise on the upstream.

关键词： stimulated small scale model smagorinsky’s eddy viscosity model Round jet, Large eddy simulation

Research on Hepatocyte Regulation of PCSK9-LDLR and Its Related Drug Targets

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Chinese Journal of Integrative Medicine 2024年第7期30卷 664-672页

作者： LIU su-su YU Tong QIAO yan-fang GU Shu-xiao CHAI Xin-lou School of Traditional Chinese Medicine Beijing University of Traditional Chinese MedicineBeijing102401China

The prevalence of hyperlipidemia has increased significantly due to genetic, dietary, nutritional and pharmacological factors, and has become one of the most common pathological conditions in humans. Hyperlipidemia can lead to a range of diseases such as atherosclerosis, stroke, coronary heart disease, myocardial infarction, diabetes, and kidney failure, etc. High circulating low-density lipoprotein cholesterol (LDL-C) is one of the causes of hyperlipidemia. LDL-C in the blood binds to LDL receptor (LDLR) and regulates cholesterol homeostasis through endocytosis. In contrast, proprotein convertase subtilisin/kexin type 9 (PCSK9) mediates LDLR degradation via the intracellular and extracellular pathways, leading to hyperlipidemia. Targeting PCSK9-synthesizing transcription factors and downstream molecules are important for development of new lipid-lowering drugs. Clinical trials regarding PCSK9 inhibitors have demonstrated a reduction in atherosclerotic cardiovascular disease events. The purpose of this review was to explore the target and mechanism of intracellular and extracellular pathways in degradation of LDLR and related drugs by PCSK9 in order to open up a new pathway for the development of new lipid-lowering drugs.

关键词： hyperlipidemia proprotein convertase subtilisin/kexin type 9 low-density lipoprotein receptor intracellular pathway extracellular pathway