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Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

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Applied Mathematics and mechanics(english edition) 2024年第4期45卷 633-648页

作者： e.GHAVANLOO s.eL-BORGI school of mechanical engineering Shiraz UniversityShiraz 71963-16548Iran mechanical engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPM).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(MMs)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPM for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPM) method of multiple scales(MMs) dispersion phase velocity

Discontinuation of therapy in inflammatory bowel disease: Current views

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World Journal of Clinical Cases 2024年第10期12卷 1718-1727页

作者： Antonio meštrović Marko Kumric Josko Bozic Department of Gastroenterology University Hospital of SplitSplit 21000Croatia Department of Pathophysiology University of Split School of MedicineSplit 21000Croatia

The timely introduction and adjustment of the appropriate drug in accordance with previously well-defined treatment goals is the foundation of the approach in the treatment of inflammatory bowel disease(IBD).The therapeutic approach is still evolving in terms of the mechanism of action but also in terms of the possibility of maintaining *** patients with achieved long-term remission,the question of de-escalation or discontinuation of therapy arises,considering the possible side effects and economic burden of long-term *** each of the drugs used in IBD(5-aminosalycaltes,immunomodulators,biological drugs,small molecules)there is a risk of ***,studies show that more than 50%of patients who discontinue therapy will *** on the findings of large studies and meta-analysis,relapse of disease can be expected in about half of the patients after therapy withdrawal,in case of monotherapy with aminosalicylates,immunomodulators or biological ***,longer relapse-free periods are recorded with withdrawal of medication in patients who had previously been on combination therapies immunomodulators and anti-tumor necrosis *** needs to be stressed that randomised clinical trials regarding withdrawal from medications are still *** making a decision on discontinuation of therapy,it is important to distinguish potential candidates and predictive factors for the possibility of disease *** calprotectin level has currently been identified as the strongest predictive factor for *** other predictive factors have also been identified,such as:High Crohn's disease activity index or Harvey Bradshaw index,younger age(ears),longer disease duration(>40 years),smoking,young age of disease onset,steroid use 6-12 months before *** important factor in the decision to withdraw medication is the success of re-treatment with the same or other *** decision to discontinue therapy must be based on in

关键词： Inflammatory bowel disease Therapy discontinuation Therapy de-escalation Ulcerative colitis Crohn’s disease

A review of ethnobotanical studies reveals over 500 medicinal plants in Mindanao,Philippines

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Plant Diversity 2024年第5期46卷 551-564页

作者： Joeime F.meñiza Monica M.Pasco Jemer A.Alimbon Department of Teacher education UM Tagum CollegeTagum City8100Davao del Norte Philippines

medicinal plants have long been used to treat various diseases in both indigenous and non-indigenous populations of Mindanao,***,we extracted data from ethnobotanical studies to compile a comprehensive list of these medicinal plants and identify how and for what purpose they are most commonly *** identified 530 verified medicinal plant species across 372 genera in 118 *** two most frequently cited species were euphorbia hirta and Psidium *** most represented family was Fabaceae and the most represented genus was Ficus.A total of 28 medicinal plant species are designated as threatened at the national or global level;of these,11 are endemic to the *** plant preparations most commonly use leaves for oral administration to treat various diseases such as digestive issues,including *** study underscores the need for further ethnobotanical investigations,particularly in areas lacking *** also emphasizes the need for conservation of threatened and endemic medicinal plants to ensure sustainable utilization of this valuable resource.

关键词： ethnobotany medicinal plants Mindanao Philippines

evaluation of the seismic behavior of reinforced concrete structures with flat slab-column gravity frame and shear walls through nonlinear analysis methods

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earthquake engineering and engineering Vibration 2024年第3期23卷 713-726页

作者： M.A.Najafgholipour s.Heidarian Radbakhsh e.erfani Department of Civil and environmental engineering Shiraz University of TechnologyShiraz ***Iran Department of Building Civiland Environmental EngineeringConcordia UniversityMontréal H3G 1M8Canada

This paper presents an investigation of the seismic behavior of reinforced concrete(RC)structures in which shear walls are the main lateral load-resisting elements and the participation of flat slab floor systems is not considered in the seismic design *** this regard,the behavior of six prototype structures(with different heights and plan layouts)is investigated through nonlinear static and time history analyses,implemented in the Opensees *** results of the analyses are presented in terms of the behavior of the slab-column connections and their mode of failure at different loading ***,the global response of the buildings is discussed in terms of some parameters,such as lateral overstrength due to the gravity flat slab-column *** to the nonlinear static analyses,in structures in which the slab-column connections were designed only for gravity loads,the slab-column connections exhibited a punching mode of failure even in the early stages of ***,the punching failure was eliminated in structures in which a minimum transverse reinforcement recommended in ACI 318(2019)was provided in the slabs at joint ***,despite neglecting the contribution of gravity flat slab-column frames in the lateral load resistance of the structures,a relatively significant overstrength was imposed on the structures by the gravity frames.

关键词： RC flat slab-column frames seismic behavior nonlinear analysis time history analysis

emission colour tuning in KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)phosphor

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Journal of Rare earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri e Vijayatha V Ramasubramanian s Thiyagarajan P Department of science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of Physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths energy transfer upconversion Downshifting Colour coordinates

Adipose-derived regenerative therapies for the treatment of knee osteoarthritis

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World Journal of stem Cells 2024年第4期16卷 324-333页

作者： Ilias e epanomeritakis Wasim s Khan Division of Trauma and Orthopaedic surgery Addenbrooke’s HospitalCambridge University Hospitals NHS Foundation TrustCambridge CB20QQUnited Kingdom Division of Trauma and Orthopaedic surgery Department of SurgeryUniversity of CambridgeCambridge CB20QQUnited Kingdom

Knee osteoarthritis is a degenerative condition with a significant disease burden and no disease-modifying *** treatment ultimately requires joint *** capable of regenerating cartilage could significantly reduce financial and clinical *** regenerative potential of mesenchymal stromal cells(MsCs)has been extensively studied in the context of knee *** has yielded promising results in human studies,and is likely a product of immunomodulatory and chondroprotective biomolecules produced by MsCs in response to ***-derived MsCs(AsCs)are becoming increasingly popular owing to their relative ease of isolation and high proliferative *** vascular fraction(sVF)and micro-fragmented adipose tissue(MFAT)are produced by the enzymatic and mechanical disruption of adipose tissue,*** avoids expansion of isolated AsCs ex vivo and their composition of heterogeneous cell populations,including immune cells,may potentiate the reparative function of *** this editorial,we comment on a multicenter randomized trial regarding the efficacy of MFAT in treating knee *** discuss the study’s findings in the context of emerging evidence regarding adipose-derived regenerative *** underlying mechanism of action of AsCs is proposed while drawing important distinctions between the properties of isolated AsCs,sVF,and MFAT.

关键词： Knee osteoarthritis mesenchymal stromal cells Adipose tissue stromal vascular fraction Micro-fragmented adipose tissue Regeneration

Analysis of mid-spatial frequency wavefront distortions from a liquid-cooled flash-lamp pumped Nd:phosphate laser amplifier

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High Power Laser science and engineering 2024年第1期12卷 24-29页

作者： Pierre-Marie Dalbies sandy Cavaro edouard Bordenave Nathalie Blanchot Julien G.Moreau Jérôme Neauport CeA CesTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

spatiotemporal dynamics in butterfly hybrid zones

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Insect science 2024年第2期31卷 328-353页

作者： Ananda R.Pereira Martins natalie B.Warren W.Owen McMillan Rowan D.H.Barrett Redpath Museum McGill University859 Sherbrooke Street WestMontrealQuebecCanada smithsonian Tropical ResearchInstitute GamboaPanama CityPanama

evaluating whether hybrid zones are stable or mobile can provide novelinsights for evolution and conservation biology. Butterflies exhibit high sensitivity to envi-ronmental changes and represent an important model system for the study of hybrid zoneorigins and maintenance. Here, we review the literature exploring butterfly hybrid zones,with a special focus on their spatiotemporal dynamics and the potential mechanisms thatcould lead to their movement or stability. We then compare different lines of evidenceused to investigate hybrid zone dynamics and discuss the strengths and weaknesses ofeach approach. Our goal with this review is to reveal general conditions associated withthe stability or mobility of butterfly hybrid zones by synthesizing evidence obtained us-ing different types of data sampled across multiple regions and spatial scales. Finally, wediscuss spatiotemporal dynamics in the context of a speciation/divergence continuum, therelevance of hybrid zones for conservation biology, and recommend key topics for futureinvestigation.

关键词： butterflies human impacts hybrid zones movement spatiotemporaldynamics stability

Chromomagnetic dipole moments of light quarks in the bestest little Higgs model

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Chinese Physics C 2024年第10期48卷 125-136页

作者： T.Cisneros-Pérez e.Cruz-Albaro A.Y.Ojeda-Castañeda s.e.solís-Núñez Unidad Académica de Ciencias Químicas Universidad Autónoma de ZacatecasApartado Postal C-58598060 ZacatecasMexico Facultad de Física Universidad Autónoma de ZacatecasApartado Postal C-58098060 ZacatecasMexico

In this study,we investigated the anomalous Chromomagnetic Dipole Moment(CMDM),denoted as μ_(q)^(BLHM),of light quarks q=(u,c,d,s,b) within the framework of the Bestest Little Higgs Model(BLHM)as an extension of the standard Model(sM).Our investigation encompassed novel interactions among the light quarks,heavy quark B,and heavy bosons (W'^(±),H^(±),φ^(±),η^(±))incorporating the extended Cabibbo-Kobayashi-Maskawa(CKM)matrix characteristic of the *** thoroughly explored the permissible parameter space,yielding a spectrum of CMDM values ranging from 10^(-10) to 10^(-3).

关键词： beyond standard model flavor physics chromomagnetic dipole light quarks