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Effects of layer interactions on instantaneous stability of finite Stokes flows

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 69-84页

作者： chen ZHAO Zhenli cHEN c.t.MUtASA Dong LI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

the stability analysis of a finite Stokes layer is of practical importance in flow control. In the present work, the instantaneous stability of a finite Stokes layer with layer interactions is studied via a linear stability analysis of the frozen phases of the base flow. the oscillations of two plates can have different velocity amplitudes, initial phases, and frequencies. the effects of the Stokes-layer interactions on the stability when two plates oscillate synchronously are analyzed. the growth rates of two most unstable modes when δ t equal, and δ = δ*/h*, where δ*and h*are the Stokes-layer thickness and the half height of the channel, respectively. However, their vorticities are different. the vorticity of the most unstable mode is symmetric, while the other is asymmetric. the Stokes-layer interactions have a destabilizing effect on the most unstable mode when δ tabilizing effect when δ > 0.68. However, the interactions always have a stabilizing effect on the other unstable mode. It is explained that one of the two unstable modes has much higher dissipation than the other one when the Stokes-layer interactions are strong. We also find that the stability of the Stokes layer is closely related to the inflectional points of the base-flow velocity profile. the effects of inconsistent velocity-amplitude, initial phase, and frequency of the oscillations on the stability are analyzed. the energy of the most unstable eigenvector is mainly distributed near the plate of higher velocity amplitude or higher oscillation frequency. the effects of the initial phase difference are complicated because the base-flow velocity is extremely sensitive to the initial phase.

关键词： finite Stokes layer instantaneous stability Stokes-layer interaction asynchronous oscillation

Near resonance vibration isolation on a levered-dual response(LEDAR)coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： t.I.tOLUWALOJU c.K.tHEIN D.HALIM Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo china Beacons of Excellence Research and Innovation Institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

the levered-dual response(LEDAR)coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio coulomb damping preload tension/compression isolation band/depth offset potential

Multiplicity of solutions for the semilinear subelliptic Dirichlet problem

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Science china Mathematics 2024年第3期67卷 475-504页

作者： Hua chen Hong-ge chen Jin-Ning Li Xin Liao School of Mathematics and Statistics Wuhan UniversityWuhan 430072China Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China

In this paper,we study the semilinear subelliptic equation{−△Xu=f(x,u)+g(x,u)inΩ,u=0 on∂Ω,where△X=−∑m i=1 Xi∗Xi is the self-adjoint Hormander operator associated with the vector fields X=(X_(1),X_(2),...,X_(m))satisfying the Hormander's condition,f(x,u)∈c(Ω×R),g(x,u)is a carathéodory function onΩ×R,andΩis an open bounded domain in R~n with smooth *** the perturbation from the symmetry method with the approaches involving the eigenvalue estimate and the Morse index in estimating the minimax values,we obtain two kinds of existence results for multiple weak solutions to the problem ***,we discuss the difference between the eigenvalue estimate approach and the Morse index approach in degenerate *** with the classical elliptic cases,both approaches here have their own strengths in the degenerate *** new phenomenon implies that the results in general degenerate cases would be quite different from the situations in classical elliptic cases.

关键词： degenerate elliptic equations Hormander operators perturbation method Morse index

Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu t.W.Huang K.Jiang c.N.Wu H.Peng P.c.hen R.Li H.B.Zhuo c.t.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

HI in High Gas-phase Metallicity Dwarf Galaxy WISEA J230615.06+143927.9

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Research in Astronomy and Astrophysics 2024年第1期24卷 292-299页

作者： Yan Guo c.Sengupta t.c.Scott P.Lagos Y.Luo Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China Institute of Astrophysics and Space Sciences(IA Porto) Rua das Estrelas4150-762PortoPortugal

We present resolved Giant Metrewave Radio telescope H I observations of the high gas-phase metallicity dwarf galaxy WISEA J230615.06+143927.9(z = 0.005)(hereafter J2306) and investigate whether it could be a tidal Dwarf Galaxy(tDG) candidate. tDGs are observed to have higher metallicities than normal dwarfs. J2306 has an unusual combination of a blue g-r color of 0.23 mag, irregular optical morphology and high-metallicity(12 +log(O/H) = 8.68 ± 0.14), making it an interesting galaxy to study in more detail. We find J2306 to be an H I rich galaxy with a large extended, unperturbed rotating H I disk. Using our H I data we estimated its dynamical mass and found the galaxy to be dark matter(DM) dominated within its H I radius. the quantity of DM, inferred from its dynamical mass, appears to rule out J2306 as an evolved tDG. A wide area environment search reveals J2306 to be isolated from any larger galaxies which could have been the source of its high gas metallicity. Additionally, the H I morphology and kinematics of the galaxy show no indication of a recent merger to explain the *** detailed optical spectroscopic observations of J2306 might provide an answer to how a seemingly ordinary irregular dwarf galaxy achieved such a high level of metal enrichment.

关键词： galaxies:abundances galaxies:dwarf galaxies:irregular radio lines:galaxies radio lines:ISM

tumor microenvironment-activatable neuropeptide-drug conjugates enhanced tumor penetration and inhibition via multiple delivery pathways and calcium deposition

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chinese chemical Letters 2024年第4期35卷 292-297页

作者： Yi cao Xiaojiao ge Yuanyuan Wei Lulu He Aiguo Wu Juan Li Ningbo Key Laboratory of Biomedical Imaging Probe Materials and technology Zhejiang International Cooperation Base of Biomedical Materials Technology and ApplicationChinese Academy of Sciences(CAS)Key Laboratory of Magnetic Materials and DevicesNingbo Cixi Institute of Biomedical EngineeringZhejiang Engineering Research Center for Biomedical MaterialsNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of chinese Academy of Sciences Beijing 100049China Advanced Energy Science and technology Guangdong Laboratory Huizhou 516000China

Peptide-drug conjugates have achieved considerable development and application as a novel strategy for targeted delivery of anticancer drugs. Bioactive peptides induced calcium deposition can irreversibly assist inhibition of tumors. However, active regulation of calcium level through signal transduction of bioactive substances has not been reported yet. In this study, novel neuropeptide-doxorubicin conjugates(NP-DOX) with lysosome-specific acid response were described for neuropeptide Y_1 receptor(Y_1R)-overexpressed triple-negative breast cancer. the delivery mechanism of NP-DOX was clarified that diverse pathways were involved, including intracellular and intercellular transport. Importantly, up-regulation of Y_1 R-mediated intracellular calcium level via second messenger inositol triphosphate was presented in NP-DOX treated MDA-MB-231 cells. In vivo antitumor efficacy demonstrated that NP-DOX showed less organ toxicity and enhanced tumor inhibition benefited from its controlled release and Y_1R-mediated calcium deposition, compared with free DOX. this bioconjugate is a proof-of-concept confirming that neuropeptide-mediated control of signaling responses in neuropeptide-drug conjugates enables great potential for further applications in tumor chemotherapy.

关键词： Neuropeptide-drug conjugate tumor penetration calcium deposition tumor inhibition triple-negative breast cancer

Evaluation of teplizumab's efficacy and safety in treatment of type 1 diabetes mellitus:A systematic review and meta-analysis

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World Journal of Diabetes 2024年第7期15卷 1615-1626页

作者： Xiao-Lan Ma Dan ge Xue-Jian Hu Department of Endocrinology and Metabolism The Second Affiliated Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina

BAcKGROUND Islets of Langerhans beta cells diminish in autoimmune type 1 diabetes mellitus(t1DM).teplizumab,a humanized anti-cD3 monoclonal antibody,may help *** long-term implications on clinical t1DM development,safety,and efficacy are *** to assess the effectiveness and safety of teplizumab as a therapeutic intervention for individuals with *** A systematic search was conducted using four electronic databases(PubMed,Embase,Scopus,and cochrane Library)to select publications published in peerreviewed journals written in *** odds ratio(OR)and risk ratio(RR)were calculated,along with their 95%*** assessed heterogeneity using cochrane Q and I2 statistics and the appropriate P *** there were 8 randomized controlled trials(Rcts)in the current meta-analysis with a total of 1908 t1DM patients from diverse age cohorts,with 1361 patients receiving teplizumab and 547 patients receiving a *** was found to have a substantial link with a decrease in insulin consumption,with an OR of 4.13(95%cI:1.72 to 9.90).teplizumab is associated with an improved cpeptide response(OR 2.49;95%cI:1.62 to 3.81)and a significant change in Glycated haemoglobin A1c(HbA1c)levels in people with type 1 diabetes[OR 1.75(95%cI:1.03 to 2.98)],and it has a RR of 0.71(95%cI:0.53 to 0.95).cONcLUSION In type 1 diabetics,teplizumab decreased insulin consumption,improved c-peptide response,and significantly changed HbA1c levels with negligible side *** appears to improve glycaemic control and diabetes management with good safety and efficacy.

关键词： type-1 diabetes mellitus teplizumab Anti-cD3 monoclonal antibody Insulin Glycated haemoglobin A1c cpeptide

Radiative decays D*(s)→ D(s)γ in covariant confined quark model

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chinese Physics c 2024年第2期48卷 45-56页

作者： c.t.tran M.A.Ivanov P.Santorelli Q.c.Vo Department of Physics HCMC University of Technology and EducationVo Van Ngan 1700000 Ho Chi Minh CityVietnam Bogoliubov Laboratory of theoretical Physics Joint Institute for Nuclear Research141980 DubnaRussia Dipartimento di Fisica"E.Pancini" Universitàdi Napoli Federico ⅡComplesso Universitario di Monte S.AngeloVia CintiaEdificio 680126 NapoliItaly Istituto Nazionale di Fisica Nucleare Sezione di Napoli80126 NapoliItaly University of Science 700000 Ho Chi Minh CityVietnam

Radiative decays D((s))*→D((s))γare revisited in light of new experimental data from the BaBar and BESⅢ*** radiative couplings gD*Dγencoding nonperturbative QcD effects are calculated in the framework of the covariant confined quark model developed by *** compare our results with other theoretical studies and experimental *** couplings(in geV-1)|g(D*+D+γ)|=0.45(9)and|g(D*0D0γ)|=1.72(34)calculated in our model agree with the corresponding experimental data|g(D*+D+γ)|=0.47(7)and|g(D*0D0γ)|=1.77(16).the most interesting case is the decay Ds*→Dsγ,for which a recent prediction based on light-cone sum rules at next-to-leading order|gDs*Dsγ|=0.60(19)deviates from the first(and only to date)lattice QcD result|gDs*Dsγ|=0.11(2)at nearly3σ.Our calculation yields|gDs*Dsγ|=0.29(6),which falls somehow between the two mentioned results,although it is larger than those predicted in other studies using quark models or QcD sum rules.

关键词： covariant quark model radiative decay charmed meson

Finite barrier bound state

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Light(Science & Applications) 2024年第4期13卷 664-671页

作者： tao Liu Kai Bai Yicheng Zhang Duanduan Wan Yun Lai c.t.chan Meng Xiao Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education and School of Physics and technology Wuhan University430072 WuhanChina. National Laboratory of Solid State Microstructures School of Physicsand Collaborative Innovation Center of Advanced MicrostructuresNanjing University210093 NanjingChina. Department of Physics The Hong Kong University of Science and TechnologyClear Water BayKowloon999077Hong KongChina. Wuhan Institute of Quantum technology 430206 WuhanChina

A boundary mode localized on one side of a finite-size lattice can tunnel to the opposite side which results in unwanted *** wisdom tells that the tunneling probability decays exponentially with the size of the system which thus requires many lattice sites before eventually becoming negligibly *** we show that the tunneling probability for some boundary modes can apparently vanish at specific ***,similar to bound states in the continuum,a boundary mode can be completely trapped within very few lattice sites where the bulk bandgap is not even *** intriguingly,the number of trapped states equals the number of lattice sites along the normal direction of the *** provide two configurations and validate the existence of this peculiar finite barrier-bound state experimentally in a dielectric photonic crystal at microwave *** work offers extreme flexibility in tuning the coupling between localized states and channels as well as a new mechanism that facilitates unprecedented manipulation of light.

关键词： boundary state eventually