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effects of nano-voids and nano-cracks on the elastic properties of a host medium: xfem modeling with level-set function and free surface energy

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Acta Mechanica Sinica 2019年第4期35卷 799-811页

作者： b.e. hachi D. hachi M. Haboussi Laboratoire de Développement en Mécanique et Matériaux (LDMM) Université de Djelfa PB 3117 Djelfa Algérie Laboratoire d’Automatique Appliquée et Diagnostics Industriels (LAADI) Université de Djelfa PB 3117 Djelfa Algérie Laboratoire des Sciences des Procédés et des Matériaux (LSPM) Université Paris 13 UPR 3407 CNRS Paris France

This work deals with the influences of nano-heterogeneities in the form of voids/cavities or cracks on the elastic (please confirm which word is correct. effective or elastic? According to the title of paper, I choose elastic.) properties of a host medium. With a relatively large ratio of apparent-surface to volume and particularly strong physical interactions with the surrounding medium at nano-scale, nano-heterogeneities can potentially affect the elastic(effective or elastic?) properties of the parent medium (matrix) containing them in a significant manner. This has b.e. reported by various theoretical and experimental studies, some of them are discussed in the present paper. To describe the positive (reinforcement) or negative (degradation) effect of the nano-heterogeneities from the modeling perspective, it is necessary to take into account the energy of interfaces/surfaces between nano-heterogeneities and the matrix which, by the fact of the relatively large extent of their apparent surface and their strong physical interaction with their neighborhood, can no longer be neglected compared to those of the volume energy. Thus, to account for the effects of interfaces/surfaces in a nanostructured heterogeneous medium, the coherent interface model is considered in the present investigation within a periodic homogenization procedure. In this interface/surface model, the displacement vector is assumed to be continuous across the interface while the stress vector is considered to be discontinuous and satisfying the Laplace-Young equations. To solve these equations coupled to the classical mechanical equilibrium prob.e., a numerical simulation tool is developed in a two-dimensional (2D) context using the eXtended Finite element Method (XFeM) and the Level-Set functions. The developed numerical tool is then used to carry out a detailed analysis about the effect of nano-heterogeneities on the overall mechanical properties of a medium. The nano-heterogeneities are present

关键词： Interface/Surface energy XFeM Level-Set function Periodic homogenization Nano-voids/Nano-cavities Nano-cracks Nano-inclusions/Nano-heterogeneities

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A systematic scoping review of study methodology for randomized controlled trials investigating probiotics in athletic and physically active populations

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Journal of Sport and Health Science 2024年第1期13卷 61-71页

作者： Alex e.Mohr David b.Pyne Geovana Silva Fogaça Leite Deborah Akins Jamie Pugh College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Research Institute for Sport and exercise University of CanberraCanberraACT 2617Australia Laboratory of Functional Fermented Food Faculty of Pharmaceutical SciencesUniversity of São PauloSão Paulo 05508-030Brazil Research Institute for Sport and exercise Sciences Liverpool John Moores UniversityLiverpool L33AFUK

background:The purported ergogenic and health effects of probiotics have b.e. a topic of great intrigue among researchers,practitioners,and the lay public *** has also b.e. an increased research focus within the realm of sports science and exercise medicine on the athletic gut ***,compared to other ergogenic aids and dietary supplements,probiotics present unique study *** ob.e.tives of this systematic scoping review were to identify and characterize study methodologies of randomized controlled trials investigating supplementation with probiotics in athletes and physically active ***:Four databases(MeDLINe,CINAHL,Cochrane CeNTRAL,and Cochrane Database of Systematic Reviews)were searched for randomized controlled studies involving healthy athletes or physically active *** intervention with probiotics and inclusion of a control and/or placebo group were *** peer-reviewed articles in english were considered,and there were no date *** were extracted and presented in tabular form to detail study protocols,characteristics,and *** in randomized controlled trials was determined with the Rob 2.0 ***:A total of 45 studies were included in the review,with 35 using a parallel group design and 10 using a cross-over *** half the studies used a single probiotic and the other half a multi-strain *** probiotic dose ranged from 2×10^(8)to 1×10^(11)colony forming units daily,and the length of intervention was between 7 and 150 *** than half the studies directly assessed gastrointestinal symptoms,gut permeability,or the gut *** sex ratio of participants was heavily weighted toward males,and only 3 studies exclusively investigated ***-level adverse events were reported in only 2 studies,although the methodology of reporting varied *** risk of bias was generally low,although details on randomization were lacking in some s

关键词： exercise experimental methodology Gastrointestinal symptoms Gut microbiota Probiotic supplementation

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Cellulose synthesis in land plants

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Molecular Plant 2024年第2期17卷 359-361页

作者： Gustav b.Pedersen Leonard blaschek Kristian e.H.Frandsen Lise C.Noack Staffan Persson 不详

After the original publication of the above article,we and/or attentive readers identified several instances of unclear or erroneous writing that needed correcting,as *** are added for emphasis.

关键词： synthesis instance identif

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RbC aggregation,deformation and adhesion to endothelium:Role of nitric oxide derived from L-Arginine and sodium nitroprusside

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 53-65页

作者： M.K.Maksimov P.b.e.molinskiy O.N.Scheglovitova N.N.Sklyankina A.V.Muravyov A.e.Lugovtsov A.V.Priezzhev Faculty of Physics M.V.Lomonosov Moscow State University bld.1subbuilding.2Leninskie goryMoscow 11991Russia N.F.Gamaleya National Research Center for epidemiology and Microbiology 18 Gamaleya StreetMoscow 123098Russia K.D.Ushinsky Yaroslavl State Pedagogical University 108/1 Respublikanskaya StreetYaroslavl 150000Russia

Red blood cells(RbCs)are the most abundant human blood *** aggregation and deformation strongly determine blood viscosity which impacts hemorheology and *** turn,RbC properties depend on di®erent endogenous and exogenous *** such factor is nitric oxide(NO),which is mainly produced by endothelial cells(eC)from L-arginine amino acid in the circulatory *** the mechanisms of the RbC-endothelium interplay are not clear up to date and considering its possib.e.clinical importance,the aims of this study are to investigate in vitro:(1)The e®ect of L-arginine induced NO on RbC aggregation and adhesion to endothelium;(2)the NO e®ect on RbC aggregation and deformation induced by L-arginine and sodium nitroprusside without the presence of endothelium in the *** RbC aggregation and adhesion to a monolayer of eC were studied using optical tweezers(OT).The RbC deformability and aggregation without endothelium in the samples were studied using the°ow chamber method and Myrenne *** con¯rmed that NO increases deformability and decreases aggregation of *** showed that the solub.e.guanylate cyclase pathway appears to be the only NO signaling pathway *** the samples with the endothelium,the\bell-shaped"dependence of RbC aggregation force on L-arginine concentration was ob.e.ved,which improves our knowledge about the process of NO production by ***,data related to L-arginine accumulation by endothelium were obtained:Necessity of the presence of extracellular L-arginine stated by other authors was put under *** our study,NO decreased the RbC-endothelium adhesion,however,the tendency appeared to be weak and was not con¯rmed in another set of *** our knowledge,this is the¯rst attempt to measure the forces of RbC adhesion to endothelium monolayer with OT.

关键词： Red blood cells aggregation L-arginine endothelium optical tweezers Myrenne flow chamber

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epidemiologic investigation of pediatric distal humerus fractures: An American insurance claims database study

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World Journal of Orthopedics 2024年第1期15卷 52-60页

作者： Kyle Jay Klahs Jake e Dertinger Grant T Mello Kevin Thapa Alexis b Sandler e'Stephan J Jesus Garcia Nata Parnes Department of Orthopaedic Surgery Texas Tech University Health Sciences-El PasoEl PasoTX 79905United States Medical School California Health Sciences University College of Osteopathic MedicineClovisCA 93611United States Undergraduate School Binghampton UniversityVestalNY 13902United States Department of Orthopaedic Surgery William Beaumont Army Medical CenterFort BlissTX 79918United States Department of Orthopaedic Surgery Carthage Area HospitalCarthageNY 13619United States

bACKGROUND Distal humerus elbow fractures are one of the most common traumatic fractures seen in pediatric patients and present as three main types:Supracondylar(SC),lateral condyle(LC),and medial epicondyle(Me)*** To evaluate the epidemiology of pediatric distal humerus fractures(SC,LC,and Me)from an American insurance claims *** A retrospective review was performed on patients 17 years and younger with the ICD 9 and 10 codes for SC,LC and Me fractures based on the IbM Truven MarketScan®Commercial and IbM Truven MarketScan Medicare Supplemental *** from 2015 to 2020 were queried for treatments,patient age,sex,length of hospitalization,and *** A total of 1133 SC,154 LC,and 124 Me fractures were *** fractures had the highest percentage of operation at 83%,followed by LC(78%)and Me fractures(41%).Male patients were,on average,older than female patients for both SC and Me *** In the insurance claims databases used,SC fractures were the most reported,followed by LC fractures,and finally Me *** was identified to be a factor for how a pediatric distal humerus fractures,with patients with SC and LC fractures being younger than those with Me *** peak age per injury per sex was similar to reported historic central tendencies,despite reported trends for younger physiologic development.

关键词： Supracondylar humerus fracture Lateral condyle fracture Medial epicondyle fracture Pediatric elbow Truven epidemiology

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evaluation of stress intensity factors for bi-material interface cracks using displacement jump methods

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Acta Mechanica Sinica 2017年第6期33卷 1051-1064页

作者： K. C. Nehar b. e. hachi F. Cazes M. Haboussi Laboratoire de développement en mécanique et matériaux (LDMM) Université de Djelfa PB 3117 Djelfa Algeria Laboratoire des Sciences des Procédés et des Matériaux (LSPM) UPR 3407 CNRS Université Paris 13 Paris France

The aim of the present work is to investigate the numerical modeling of interfacial cracks that may appear at the interface between two isotropic elastic materials. The extended finite element method is employed to analyze brittle and bi-material interfacial fatigue crack growth by computing the mixed mode stress intensity factors(SIF). Three different approaches are introduced to compute the SIFs. In the first one, mixed mode SIF is deduced from the computation of the contour integral as per the classical J-integral method,whereas a displacement method is used to evaluate the SIF by using either one or two displacement jumps located along the crack path in the second and third approaches. The displacement jump method is rather classical for mono-materials,but has to our knowledge not b.e. used up to now for a bimaterial. Hence, use of displacement jump for characterizing bi-material cracks constitutes the main contribution of the present study. Several benchmark tests including parametric studies are performed to show the effectiveness of these computational methodologies for SIF considering static and fatigue prob.e.s of bi-material structures. It is found that results based on the displacement jump methods are in a very good agreement with those of exact solutions, such as for the J-integral method, but with a larger domain of applicability and a better numerical efficiency(less time consuming and less spurious boundary effect).

关键词： bi-material interface crack Mixed mode stress intensity factor Displacement jump X-FeM Fatigue crack growth

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CLASSIFICATIONS OF DUPIN HYPeRSURFACeS IN LIe SPHeRe GeOMeTRY

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Acta Mathematica Scientia 2024年第1期44卷 1-36页

作者： Thomas e.CeCIL Department of Mathematics and Computer Science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in S^(n)(or R^(n))that have b.e. obtained in the context of Lie sphere *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of S^(n)(or R^(n)),are described in *** paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures

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Audio-frequency heating of particulate magnetic systems

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China Particuology 2007年第1期5卷 84-92页

作者： b.e. Kashevsky I.V. Prokhorov S.b. Kashevsky A.V. Luikov Heat and Mass Transfer Institute Belarus Academy of Sciences P. Brovka str. 15 Minsk 220072 Belarus

This paper presents theoretical and experimental studies on the magnetodynamics and energy dissipation in suspensions of small ferromagnetic particles with magnetic hysteresis and mechanical mobility in an AC magnetic field. energy absorption by particles suspended in a solid, liquid or gas environment and sub.e.ted to high frequency magnetic fields is of great interest for cancer treatment by hyperthermia, chemical technology, biotechnology and smart materials science. Sub-micron needle-like γ-Fe2O3 particles dispersed in liquid were sub.e.ted in this study to a 430 Hz magnetic field with an intensity of up to 10^5 A/m. Dynamic magnetization loops were measured in parallel to the energy dissipated in the samples. Combined magnetomechanical dynamics of particle dispersions was simulated by using a chain-of-spheres model allowing for incoherent magnetic field reversal. In liquid dispersions, within the kilohertz frequency range, the mechanical mobility of particles does not interfere with their hysteretic magnetic reversal that makes heat release comparab.e.to that ob.e.ved with solids; for instance, in the present study using γ-Fe2O3 particles in liquid sub.e.ted to 10^4 Hz field exhibited heat release rates from 250 up to 600W oer 1 cm^3 of the dry oarticle content.

关键词： AC magnetic field Particulate materials Audio-frequency heating

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A rat model of multicompartmental traumatic injury and hemorrhagic shock induces bone marrow dysfunction and profound anemia

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Animal Models and experimental Medicine 2024年第3期7卷 367-376页

作者： Lauren S.Kelly Jennifer A.Munley erick e.Pons Kolenkode b.Kannan elizabeth M.Whitley Letitia e.bib.e.Philip A.efron Alicia M.Mohr Department of Surgery and Sepsis and Critical Illness Research Center University of Florida College of MedicineGainesvilleFloridaUSA Pathogenesis LLCGainesvilleFloridaUSA

background:Severe trauma is associated with systemic inflammation and organ *** rodent trauma models are the mainstay of postinjury research but have b.e. criticized for not fully replicating severe human *** aim of this study was to create a rat model of multicompartmental injury which recreates profound traumatic ***:Male Sprague-Dawley rats were sub.e.ted to unilateral lung contusion and hemorrhagic shock(LCHS),multicompartmental polytrauma(PT)(unilateral lung contusion,hemorrhagic shock,cecectomy,bifemoral pseudofracture),or na?ve ***,plasma toll-l ike receptor 4(TLR4),hemoglobin,spleen to body weight ratio,bone marrow(bM)erythroid progenitor(CFU-GeMM,bFU-e,and CFU-e)growth,plasma granulocyte colony-stimulating factor(G-CSF)and right lung histologic injury were assessed on day 7,with significance defined as p valuesesults:Polytrauma resulted in markedly more profound inhibition of weight gain compared to LCHS(p=0.0002)along with elevated plasma TLR4(per hemoglobin(penlarged spleen to body weight ratios(p=0.004).both LCHS and PT demonstrated suppression of CFU-e and bFU-e growth compared to naive(pelevated in PT compared to both na?ve and LCHS(pemonstrated significant histologic right lung injury with poor alveolar wall integrity and interstitial ***:Multicompartmental injury as described here establishes a reproducib.e.model of multicompartmental injury with worsened anemia,splenic tissue enlargement,weight loss,and increased inflammatory activity compared to a less severe *** may serve as a more effective model to recreate profound traumatic injury to replicate the human inflammatory response postinjury.

关键词： anemia i nflammation polytrauma pseudofracture shock

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experimental measurements of gamma-photon production and estimation of electron/positron production on the PeTAL laser facility

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Matter and Radiation at extremes 2024年第5期9卷 32-47页

作者： F.brun L.Ribotte G.boutoux X.Davoine P.e.Masson-Laborde Y.Sentoku N.Iwata N.blanchot D.batani I.Lantuéjoul L.Lecherbourg b.Rosse C.Rousseaux b.Vauzour D.Raffestin e.D’Humières X.Ribeyre Centre Lasers Intenses et Applications UMR 5107Universitéde Bordeaux-CNRS-CEA33405 TalenceFrance CeA DAMCESTAF-33116 Le BarpFrance CeA DAMDIFF-91297 ArpajonFrance CeA LMCEUniversitéParis-Saclay91680 Bruyères-le-ChâtelFrance Institute of Laser engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan

This article reports the first measurements of high-energy photons produced with the high-intensity PeTawatt Aquitaine Laser(PeTAL)*** experiments were performed during the commissioning of the *** laser had an energy of about 400 J,an intensity of 8×10^(18)W cm^(−2),and a pulse duration of 660 fs(FWHM).It was shot at a 2 mm-thick solid tungsten *** high-energy photons were produced mainly from the b.e.sstrahlung process for relativistic electrons accelerated inside a plasma generated on the front side of the *** paper reports measurements of electrons,protons and *** electrons up to35 MeV with a few-MeV temperature were recorded by a spectrometer,called SeSAMe(SpectreÉlectronS Angulaire MoyenneÉnergie).K-and L-shells were clearly detected by a photon spectrometer called SPeCTIX(Spectromètre PetalàCristal en TransmIssion pour le rayonnnement X).High-energy photons were diagnosed by CRACC-X(Cassette de RAdiographie Centre Chamb.e.rayonnement X),a b.e.sstrahlung *** cannon analysis is strongly dependent on the hypothesis adopted for the spectral *** shapes can exhibit similar reproductions of the experimental *** eliminate dependence on the shape hypothesis and to facilitate analysis of the data,simulations of the interaction were *** model the mechanisms involved,a simulation chain including hydrodynamic,particle-in-cell,and Monte Carlo simulations was *** simulations model the preplasma generated at the front of the target by the PeTAL laser prepulse,the acceleration of electrons inside the plasma,the generation of MeV-range photons from these electrons,and the response of the detector impacted by the energetic photon *** this work enab.e. reproduction of the experimental *** high-energy photons produced have a large emission angle and an exponential distribution *** addition to the analysis of the photon spectra,positron production was also ***,if high

关键词： process. positron hypothesis

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