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Methods of Approximation in hpk Framework for ODEs in Time Resulting from Decoupling of Space and Time in IVPs

The Sixth World Congress on Computational Mechanics in Conj.n.tion with the Second Asian-Pacific Congress on Computational MechanicsⅠ

作者： F. Rostam-Abadi j.n. reddy U.S. Army TARDEC Survivability Research Area AMSTA-TR-R Warren MI 48397 USA Department of Mechanical Engineering Texas A & M University College Station TX 77845

The objective of the research is to develop efficient computational tools for non-linear analysis of smart composites structural systems with embedded smart (e.g., piezoelectric or magnetostrictive particle) layers. The research was concerned with (1) the theoretical formulation and analytical solutions for the stress and vibration suppression of laminated plates, (2) the linear finite element analysis of laminated composite plates with smart-material layers, and (3) the linear transient analysis using the FEM and non-linear finite element formulation based on the third-order shear deformation plate theory.

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American journal of Computational Mathematics 2011年第2期1卷 83-103页

作者： K.S. Surana L. Euler j.n. reddy A. Romkes University of Kansas Mechanical Engineering Department Lawrence KS 66045

The present study considers mathematical classification of the time differential operators and then applies methods of approximation in time such as Galerkin method (GM ), Galerkin method with weak form (GM / WF ), Petrov-Galerkin method ( PGM), weighted residual method (WRY ), and least squares method or process ( LSM or LSP ) to construct finite element approximations in time. A correspondence is established between these integral forms and the elements of the calculus of variations: 1) to determine which methods of approximation yield unconditionally stable (variationally consistent integral forms, VC ) computational processes for which types of operators and, 2) to establish which integral forms do not yield unconditionally stable computations (variationally inconsistent integral forms, VIC ). It is shown that variationally consistent time integral forms in hpk framework yield computational processes for ODEs in time that are unconditionally stable, provide a mechanism of higher order global differentiability approximations as well as higher degree local approximations in time, provide control over approximation error when used as a time marching process and can indeed yield time accurate solutions of the evolution. numerical studies are presented using standard model problems from the literature and the results are compared with Wilson’s θ method as well as newmark method to demonstrate highly meritorious features of the proposed methodology.

关键词： Finite Element Approximations numerical Studies Time Approximation Variationally Consis- tent Integral Forms

The impact of maternal immune activation on the morphology and electrophysiological properties of postnatally-born neurons in the offspring

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neural Regeneration Research 2024年第2期19卷 399-400页

作者： Emilio j.Galván Angelica Zepeda Departamento de Farmacobiología CINVESTAV Unidad Sur CdMxMéxico、Centro de Investigaciones sobre el EnvejecimientoCIE-CinvestavCdMxMéxico Departamento de Medicina Genómica y Toxicología Ambiental Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de MéxicoUNAMCdMxMéxico

Pregnancy comes with a combination of physical changes and physiological immunosuppression that increases the susceptibility of women to pathogens and in turn,rises the prevalence of infectious diseases.

关键词： prevalence activation impact

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

Laparoscopic plication for diaphragmatic eventration in adults:Unveiling the mystery of eventration

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Laparoscopic, Endoscopic and Robotic Surgery 2024年第2期7卷 92-96页

作者： Balika Mahesan Prasanna Kumar reddy K.S.Santhosh Anand Muvva Sri Harsha M Vijay n Sudarsan Srikanth Department of Minimal Access Surgery Apollo HospitalsChennaiIndia Department of Surgical Gastroenterology Apollo HospitalsChennaiIndia

Diaphragm eventration is the permanent elevation of a hemidiaphragm and can be due to congenital or acquired *** is a rather uncommon condition in adults and causes a spectrum of symptoms,ranging from asymptomatic incidental findings on imaging to life-threatening respiratory *** patients do not require any treatment,but plication is the conventional,well-known method for treating symptomatic *** varies depending on the *** this article,we discuss two rare cases of diaphragmatic eventration that were treated with minimal access surgery.

关键词： Diaphragmatic eventration Minimal access surgeryLaparoscopy

Treatment of uveitis and scleritis patients in Malaysia

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International journal of Ophthalmology(English edition) 2024年第3期17卷 518-527页

作者： Sieng Teng Seow Iqbal Taj.n.sah Fei Yee Lee Pooi Wah Lott Sagili Chandrasekhara reddy Department of Ophthalmology University Malaya Eye Research Centre(UMERC)Faculty of MedicineUniversiti MalayaKuala Lumpur 59100Malaysia Clinical Research Centre Selayang HospitalMinistry of Health MalaysiaSelangor 68100Malaysia Department of Ophthalmology Faculty of Medicine and Defence HealthNational Defence University of MalaysiaKuala Lumpur 57000Malaysia

●AIM:To determine the common causes and visual outcome after treatment among uveitis and scleritis patients.●METHODS:This is a retrospective cohort observational *** consecutive clinical records of patients with newly diagnosed uveitis and scleritis over a 4-year period,from j.n.1,2017 to Dec.31,2020,were *** was collected at the presentation and included a follow-up period of one year.●RESULTS:A total of 288 patients were recruited during the study *** uveitis was the most common anatomical diagnosis(50.0%)followed by panuveitis(25.0%),scleritis(13.5%),posterior uveitis(6.9%),and intermediate uveitis(4.5%).Viral Herpes was the most common cause of infectious cases,while Vogt-Koyanagi-Harada(VKH)disease and human leucocyte antigen(HLA)B27 spondyloarthropathy were the leading causes of identifiable non-infectious *** of patients presented with unilateral,non-granulomatous uveitis with an absence of *** locations like posterior uveitis and panuveitis,and visual acuity worse than 3/60 at presentation were the factors associated with poor visual outcomes(Pnts had an identifiable cause for the uveitis and scleritis,with nearly equal distribution of infectious(n=85,29.5%)and noninfectious causes(n=84,29.2%).About 14.5%of patients were clinically blind at 1y of *** most common complication in our uveitis patients was glaucoma(47.5%),followed by cystoid macula oedema(18.9%)and cataract(13.9%).●COnCLUSIOn:Uveitis and scleritis are important causes of ocular *** are potentially blinding diseases which can have a good outcome if diagnosed and treated early.

关键词： uveitis scleritis ocular morbidity blindness aetiology

Mucopolysaccharidosis typeⅢB:a current review and exploration of the AAV therapy landscape

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neural Regeneration Research 2024年第2期19卷 355-359页

作者： Courtney j.Rouse Victoria n.j.n.en Coy D.Heldermon Lacerta Therapeutics AlachuaFLUSA University of Florida College of Medicine GainesvilleFLUSA

Mucopolysaccharidoses typeⅢB is a rare genetic disorder caused by mutations in the gene that encodes for *** results in the aggregation of heparan sulfate polysaccharides within cell lysosomes that leads to progressive and severe debilitating neurological *** treatment options are expensive,limited,and presently there are no approved cures for mucopolysaccharidoses typeⅢ***-associated virus gene therapy has significantly advanced the field forward,allowing researchers to successfully design,enhance,and improve potential *** group recently published an effective treatment using a codon-optimized triple mutant adeno-associated virus 8 vector that restores n-acetyl-alpha-glucosaminidase levels,auditory function,and lifespan in the murine model for mucopolysaccharidoses typeⅢB to that seen in healthy ***,we review the current state of the field in relation to the capsid landscape,adeno-associated virus gene therapy and its successes and challenges in the clinic,and how novel adenoassociated virus capsid designs have evolved research in the mucopolysaccharidoses typeⅢB field.

关键词： adeno-associated virus central nervous system gene therapy heparan sulfate immune response mucopolysaccharidoses type IIIB n-acetyl-alpha-glucosaminidase newborn screening

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)

A hydrodynamic modelling of wave-activated bodies for wavelet marine regions

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CLEAn EnERGY 2024年第2期8卷 35-47页

作者： Peh, j. S. Muhieldeen, Mohammed W. Shuaib, n. H. UCSI Univ Fac Engn Technol & Built Environm Mech Engn Dept Kuala Lumpur 56000 Malaysia MTC Engineer Sdn Bhd Shah Alam Selangor Malaysia

Recently, most wave energy research has targeted sea areas with high power density under extreme wave conditions for deployment. This trend often leads to higher energy costs for wave power plants. However, many marine areas with low power density, characterized by wavelet conditions and less destructive forces than extreme wave conditions, remain underexplored. Therefore, this study aimed to propose a wave-activated body model for sea regions with wavelet conditions. The wave-activated body design process encompassed site selection, parameter determination, geometry design, comparison and performance evaluation using the AnSYS (R) AQWA model. The results indicated that the proposed device achieved the desired heave motion, with an amplitude range of 1.2 to -2.5 m, validating its potential for deployment in marine regions with wavelet conditions. notably, while the proposed design is optimized for wavelet conditions, it was found to have potential limitations in extreme wave environments. This observation emphasizes the challenge of formulating a generalized design suitable for both conditions. Consequently, it is pivotal for wave-activated body designs to be customized based on the specific ocean conditions they target, underscoring the need for specialized designs of wave energy converters that consider the unique wave characteristics of their deployment sites. A wave-activated body is designed for energy generation in ocean regions with wavelet conditions. Hydrodynamic modelling is carried out for two locations with different wave characteristics to determine the optimum conditions for deployment. Graphical Abstract

关键词： wave energy converter South China sea renewable and sustainable energy wavelet AnSYS AQWA hydrodynamic wave-activated bodies EnERGY IMPACT