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World Journal of Pediatrics 2024年第2期20卷 185-188页

作者： Gerald Jarnig Reinhold Kerbl Mireille n.M.van Poppel Institute of Human Movement Science Sport and HealthUniversity of GrazMozartgasse 148010 GrazAustria Department of Pediatrics and Adolescent Medicine LKH Hochsteiermark8700 LeobenAustria

In late 2019,heavy restrictions were enforced on public activities worldwide to diminish the spread of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus[1].These restrictions,which included school closures and strictly limited sports and leisure opportunities,particularly impacted children and adolescents[2].Lifestyle changes in children and adolescents led to reduced physical activity levels[2,3],increased sedentary behavior[3,4],changes in eating habits,and changes in sleep habits[3].

关键词： respiratory acute children

A nano-plasmonic HMIM waveguide based concurrent dual-band BPF using circular ring resonator

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Optoelectronics Letters 2024年第3期20卷 152-156页

作者： Miriyala Sridhar Surendra Kumar Bitra TS n Murthy Koppireddi Padmaraju Department of Electronics and Communication Engineering Koneru Lakshmaiah Education FoundationGunturIndia Astra Microwave Products Ltd. HyderabadIndia Department of Electronics and Communication Engineering JNTU-GV College of EngineeringVizianagaramIndia Department of Electronics and Communication Engineering Jawaharlal Nehru Technological University KakinadaKakinadaIndia

This article analyzes the transmission line characteristics of plasmonic hybrid metal insulator metal(HMIM) wave-guide, circular ring resonator(CRR) based dual-band band-pass filters with two transmission poles in both pass-bands in the optical regime using coupled line feed. The transmission line characteristics of an HMIM waveguide, such as characteristic impedance(Z_(PV)), effective refractive index(n_(eff)) and propagation length(L_(spp)), have been obtained by using full wave simulation.

关键词： waveguide resonator circular

Wettability,reactivity,and interface structure in Mg/ni system

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Journal of Magnesium and Alloys 2024年第2期12卷 659-672页

作者： S.Terlicka n.Sobczak Ł.Maj P.Darłak J.J.Sobczak Institute of Metallurgy and Materials Science Polish Academy of Sciences25 Reymonta Str.KrakowPoland Faculty of Foundry Engineering AGH University23 Reymonta Str.KrakowPoland

The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure ni *** comparison,the experiments were performed in two variants:(1)using the Capillary Purification(CP)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)*** high-temperature tests were performed under isothermal conditions(CP:760℃for 30 s;CH:715℃for 300 s)using Ar+5 wt%H_(2) *** the sessile drop tests,images of the Mg/ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate *** and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified *** was found that an oxide-free Mg drop obtained by the CP procedure showed a wetting phenomenon on the ni substrate(an average contact angleθnng and good wetting over the ni substrate(θ_((CP))~20°in 5 s)to form a final contact angle ofθ_(f(CP))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test ***,in both cases,the deep craters formed in the ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-ni alloys suggest a strong dissolution of ni in liquid Mg and apparent values of the final contact angles measured for the Mg/ni system.

关键词： Magnesium-based alloys Sessile drop tests Capillary purification procedure Wettability Reactivity Contact angle

Mathematical modeling and simulations of stress mitigation by coating polycrystalline particles in lithium-ion batteries

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 947-962页

作者： n.IQBAL J.CHOI S.F.SHAH C.LEE S.LEE Department of Mechanical Roboticsand Energy EngineeringDongguk University-SeoulSeoul 04620Republic of Korea

A chemo-mechanical model is developed to investigate the effects on the stress development of the coating of polycrystalline ni-rich LinixMnyCo_(z)O_(2)(x≥0.8)(nMC)particles with poly(3,4-ethylenedioxythiophene)(PEDOT).The simulation results show that the coating of primary nMC particles significantly reduces the stress generation by efficiently accommodating the volume change associated with the lithium diffusion,and the coating layer plays roles both as a cushion against the volume change and a channel for the lithium transport,promoting the lithium distribution across the secondary particles more ***,the lower stiffness,higher ionic conductivity,and larger thickness of the coating layer improve the stress *** paper provides a mathematical framework for calculating the chemo-mechanical responses of anisotropic electrode materials and fundamental insights into how the coating of nMC active particles mitigates stress levels.

关键词： lithium-ion battery(LIB) polycrystalline particle coating finite element simulation ni-rich LinixMnyCo_(z)O_(2)(x>0.8)(nMC)

The interaction of the structure-directing agent with the zeolite framework determines germanium distribution in SCM-15 germanosilicate

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 105-114页

作者： Stoyan P.Gramatikov Petko St.Petkov Zhendong Wang Weimin Yang Georgi n.Vayssilov Faculty of Chemistry and Pharmacy University of Sofia1126 SofiaBulgaria State Key Laboratory of Green Chemical Engineering and Industrial Catalysis Sinopec Shanghai Research Institute of Petrochemical Technology Co.Ltd.Shanghai 201208China

We report results from computational modeling of the relative stability of germanosilicate SCM-15 structure due to different distribution of germanium heteroatoms in the double four-member rings(D4Rs)of the framework and the orientation of the structure directing agent(SDA)molecules in the as-synthesized *** calculated relative energies of the bare zeolite framework suggest that structures with germanium ions clustered in the same D4Rs,e.g.,with large number of Ge–O-Ge contacts,are the most *** simulations of various orientations of the SDA in the pores of the germanosilicate zeolite show different stability order-the most stable models are the structures with germanium spread among all ***,for SCM-15 the stabilization due to the presence of the SDA and their orientation,is thermodynamic factor directing both the formation of specific framework type and Ge distribution in the framework during the *** relative stability of bare structures with different germanium distribution is of minor *** differs from SCM-14 germanosilicate,reported earlier,for which the stability order is preserved in presence of ***,even for zeolites with the same chemical composition and SDA,the characteristics of their framework lead to different energetic preference for germanium distribution.

关键词： zeolite density functional theory structure-directing agent SCM-15

Current considerations for the surgical management of gallbladder adenomas

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1507-1512页

作者： Efstathios T Pavlidis Ioannis n Galanis Theodoros E Pavlidis The Second Department of Propaedeutic Surgery Hippokration General HospitalSchool of MedicineAristotle University of ThessalonikiThessaloniki 54642Greece

Gallbladder adenomas are rare lesions(0.5%)associated with potential malignant transformation,particularly with gallbladder adenomas that are≥1 cm in *** detection and management are crucial for preventing lethal carcinoma *** polyps can often be distinguished from the more often nonneo-plastic cholesterol pseudopolyps(5%-10%),which are *** is the first-line tool for initial diagnosis and follow-up when *** question is whether cholecystectomy is always necessary for all *** manage-ment of gallbladder adenomas is determined according to the size of the tumor,the growth rate of the tumor,the patient’s symptoms and whether risk factors for malignancy are ***≥1 cm in size,an age>50 years and a familial history of gallbladder carcinoma are indications for immediate laparoscopic ***,ultrasound follow-up is *** adenomas 6-9 mm in size,the absence of≥2 mm growth at 6 months,one year,and two years,as well as an adenoma sizedng risk factors indicates that no further surveillance is ***,it would be preferable to individualize the management in doubtful *** interventional modalities for preserving the gallbladder need further evaluation,especially to determine the long-term outcomes.

关键词： Biliary diseases True neoplastic polyps Gallbladder adenomas Benign bi-liary tumors Gallbladder polyps Extrahepatic biliary neoplasms

Output feedback adaptive super twisting sliding mode control for quadrotor UAVs

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Control Theory and Technology 2024年第1期22卷 92-105页

作者： Oscar Salas-Peña Jesus DeLeón-Morales Susana V.Gutiérrez-Martínez École Centrale de nantes-LS2n UMR 6004 CNRS44300NantesFrance Facultad de Ingeniería Mecánica y Eléctrica Universidad Autónoma de Nuevo León66451San Nicolás de Los GarzaMexico

In this paper, a sliding mode control with adaptive gain combined with a high-order sliding mode observer to solve the tracking problem for a quadrotor UAV is addressed, in presence of bounded external disturbances and parametric uncertainties. The high order sliding mode observer is designed for estimating the linear and angular speed in order to implement the proposed scheme. Furthermore, a Lyapunov function is introduced to design the controller with the adaptation law, whereas an analysis of finite time convergence towards to zero is provided, where sufficient conditions are obtained. Regarding previous works from literature, one important advantage of proposed strategy is that the gains of control are parameterized in terms of only one adaptive parameter, which reduces the control effort by avoiding gain overestimation. numerical simulations for tracking control of the quadrotor are given to show the performance of proposed adaptive control–observer scheme.

关键词： Adaptive super twisting controller High-order sliding modes observer UAV

nucleoside modified mRnA-lipid nanoparticles as a new delivery platform for the repair of the injured spinal cord

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neural Regeneration Research 2025年第8期20卷 2311-2312页

作者： Krisztián Pajer Tamás Bellák Antal nógrádi Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary

Spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity for spontaneous regeneration due to various intrinsic molecular and cellular *** the spinal cord neurons have the capacity to regenerate their axons,the expression of growth inhibitory factors,lack or suppression of proper guidance cues,and profound inflammatory responses do not permit successful regeneration(Khyeam et al.,2021).

关键词： injured capacity modified

An Involution over Dyck Paths Related with Stirling Statistics

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Journal of Mathematical Research with Applications 2024年第04期44卷 437-443页

作者： Peng CAO Joanna n.CHEn College of Science Tianjin University of Technology

We construct an involution over Dyck paths, which implies the distribution of statistics “the number of peak”, “the number of returns” and “the height of the last peak”. As an application, equidistributions of s... 详细信息

关键词： involutions Dyck paths pattern peak returns

Optimum Profiles of Endwall Contouring for Enhanced net Heat Flux Reduction and Aerodynamic Performance

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Journal of Harbin Institute of Technology(new Series) 2024年第2期31卷 80-92页

作者： Arjun K S Tide P S Biju n Division of Mechanical Engineering School of EngineeringCochin University of Science&TechnologyKalamassery 682022India

Successfully utilized non-axisymmetric endwalls to enhance turbine efficiencies(aerodynamic and turbine inlet temperatures)by controlling the characteristics of the secondary flow in a blade *** is accomplished by steady-state numerical hydrodynamics and deep knowledge of the field of *** of the interaction between mainstream and purge flow contributing supplementary losses in the stage,non-axisymmetric endwalls are highly susceptible to the inception of purge flow exit compared to the flat and any advantage rapidly *** conclusions reveal that the supreme endwall pattern could yield a lowering of the gross pressure loss at the design stage and is related to the size of the top-loss location being productively *** has led to diminished global thermal exchange lowered in the passage of the vane *** reverse flow adjacent to the suction side corner of the endwall is migrated farther from the vane surface,as the deviated pressure spread on the endwall accelerates the flow and progresses the reverse flow core still *** depleted association between the tornado-like vortex and the corner vortex adjacent to the suction side corner of the endwall is the dominant mechanism of control in the contoured end *** this publication,we show that the non-axisymmetric endwall contouring by selective numerical shape change method at most prominent locations is advantageous in lowering the thermal load in turbines to augment the net heat flux reduction as well as the aerodynamic performance using multi-objective optimization.

关键词： endwall contouring turbine vane heat transfer phantom cooling coolant injection net heat flux reduction aerodynamic performance