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ADeR Methods for Hyperbolic equations with a Time-Reconstruction Solver for the Generalized Riemann Problem: the Scalar Case

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Communications on Applied Mathematics and Computation 2020年第3期2卷 369-402页

作者： R.Demattè V.A.Titarev G.i.Montecinos e.F.Toro Department of Aerospace Science and Technology Politecnico di MilanoMilanItaly Dorodnicyn Computing Center Federal Research Center Computer Science and ControlRussianAcademy of SciencesMoscowRussia Departamento de Ciencias Naturales y Tecnología Universidad de AysénCoyhaiqueChile Laboratory of Applied Mathematics DICAMUniversity of TrentoTrentoItaly

The ADeR approach to solve hyperbolic equations to very high order of accuracy has seen explosive developments in the last few years,including both methodological aspects as well as very ambitious *** spite of methodological progress,the issues of efficiency and ease of implementation of the solution of the associated generalized Riemann problem(GRP)remain the centre of attention in the ADeR *** the original formulation of ADeR schemes,the proposed solution procedure for the GRP was based on(i)Taylor series expansion of the solution in time right at the element interface,(ii)subsequent application of the Cauchy-Kowalewskaya procedure to convert time de.i.a.ives to functionals of space de.i.a.ives,and(iii)solution of classical Riemann problems for high-order spatial de.i.a.ives to complete the Taylor series *** realistic problems the Cauchy-Kowalewskaya procedure requires the use of symbolic manipulators and being rather cumbersome its replacement or simplification is highly *** this paper we propose a new class of solvers for the GRP that avoid the Cauchy-Kowalewskaya procedure and result in simpler ADeR *** is achieved by exploiting the history of the nume.i.a. solution that makes it possible to devise a time-reconstruction procedure at the element *** relying on a time Taylor series expansion of the solution at the interface,the time de.i.a.ives are then easily calculated from the time-reconstruction *** resulting schemes are called ADeR-TR.A thorough study of the linear stability properties of the linear version of the schemes is carried out using the von Neumann method,thus deducing linear stability ***,via careful nume.i.a. experiments,we deduce stability regions for the corresponding non-linear *** examples using the present simplified schemes of fifth and seventh order of accuracy in space and time show that these compare favourably with conventional ADeR ***

关键词： Hyperbolic equations Finite volume ADeR methods Generalized Riemann problem(GRP) Time-reconstruction(TR)

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Clinical assessment and management of liver fibrosis in nonalcoholic fatty liver disease

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World Journal of Gastroenterology 2020年第39期26卷 5919-5943页

作者： Alejandro campos-Murguía Astrid Ruiz-Margáin JoséA González-Regueiro Ricardo U Macías-Rodríguez Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico

Non-alcoholic fatty liver disease(NAFLD)is among the most frequent etiologies of cirrhosis worldwide,and it is associated with features of metabolic syndrome;the key factor influencing its prognosis is the progression of liver *** review aimed to propose a practical and stepwise approach to the evaluation and management of liver fibrosis in patients with NAFLD,analyzing the currently available *** the assessment of NAFLD patients,it is important to identify clinical,genetic,and environmental determinants of fibrosis development and its *** properly detect fibrosis,it is important to take into account the available methods and their supporting scientific evidence to guide the approach and the sequential selection of the best available bioche.i.a. scores,followed by a complementary imaging study(transient elastography,magnetic resonance elastography or acoustic radiation force impulse)and finally a liver biopsy,when *** help with the selection of the most appropriate method a Fagan′s nomogram analysis is provided in this review,describing the diagnostic yield of each method and their post-test probability of detecting liver ***,treatment should always include diet and exercise,as well as controlling the components of the metabolic syndrome,+/-vitamin e,considering the presence of sleep apnea,and when available,allocate those patients with advanced fibrosis or high risk of progression into clinical *** final end of this approach should be to establish an opportune diagnosis and treatment of liver fibrosis in patients with NAFLD,aiming to decrease/stop its progression and improve their prognosis.

关键词： Non-alcoholic fatty liver disease Liver fibrosis Clinical assessment Diagnosis Treatment Test accuracy

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Nume.i.a. Analysis of the Behavior of A New Aeronautical Alloy (Ti555-03) Under the effect of A High-Speed Water Jet

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China Ocean engineering 2019年第1期33卷 114-126页

作者： i.Ben Belgacem L.Cheikh e.M.Barhoumi W.Khan W.Ben Salem Laboratoire de Génie Mécanique Ecole Nationale d’Ingénieurs de MonastirUniversité de Monastir institut Préparatoire aux etudes d’ingénieur de Monastir Université de Monastir Department of electrical and Computer engineering College of EngineeringDhofar University University of Waterloo institut Supérieur des Arts et Métiers de Mahdia Université de Monastir

in this paper, we present a nume.i.a. simulation of a water jet impacting a new aeronautical material Ti555-03 *** Computational Fluid Dynamics(CFD) behavior of the jet is investigated using a FV(Finite Volume) *** Fluid–Structure interaction(FSi) is studied using a coupled SPH(Smoothed Particle Hydrodynamics)-Fe(Finite element) method. The jets hit the metal sheet with an initial velocity 500 m/s. Two configurations which differ from each other by the position(angle of inclination) of the plate relatively to the axis of revolution of the jet inlet are investigated in this study. The objective of this study is to predict the impact of the fluid produced at high pressure and high speed especially at the first moment of impact. Nume.i.a. simulations are carried out under ABAQUS. We have shown in this study that the inclination of the titanium alloy plate by 45° stimulates the phenomenon of recirculation of water. This affects the velocity profile, turbulence and boundary layers in the impact zone. The stagnation zone and the phenomenon of water recirculation are strongly influenced by the slope of the plate which gives a pressure gradient and displacement very important between the two configurations. Fluctuations of physical variables(displacement and pressure) prove the need for a noise and vibratory study. These predictions will subsequently be used for the modeling of the problem of an orthogonal cut in a high-speed machining process assisted by high-pressure water jet.

关键词： Titanium alloy(Ti555-03) CFD turbulence ABAQUS Smoothed Particle Hydrodynamics(SPH) Fluid Structure interaction(FSi)

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Titanium oxide artificial synaptic device:Nanostructure modeling and synthesis,memristive cross-bar fabrication,and resistive switching investigation

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Nano Research 2023年第7期16卷 10222-10233页

作者： Vadim i.Avilov Roman V.Tominov Zakhar e.Vakulov Lev G.Zhavoronkov Vladimir A.Smirnov Research Laboratory Neuroelectronics and Memristive Nanomaterials(NeUROMeNA Lab) Southern Federal UniversityTaganrog 347922Russia institute of Nanotechnologies Electronics and Electronic Equipment EngineeringSouthern Federal UniversityTaganrog 347922Russia

The paper shows the results of the mathematical model development and the nume.i.a. simulation of the oxygen vacancies,and the distribution of TiO,Ti_(2)O_(3),and TiO_(2)oxides in the titanium oxide nanostructure obtained by local anodic oxidation(anodization).The effect of the anodization voltage pulse duration and amplitude on the titanium oxide composition distribution and the conduction channel formation was *** device prototypes based on electroche.i.a. titanium oxide are fabricated and *** was shown that forming free resistive switching between the low resistances state(LRS)1.43±0.54 kΩand the high resistance state(HRS)28.75±9.75 kΩwere observed during 100,000 switching cycles and LRS 1.49±0.23 kΩwas maintained for 10,000 *** resistive switching of the synaptic device prototype was *** was shown that increasing Uset from 0.5 to 1.5 V leads to different LRS from 3.96±0.19 to 0.71±0.10 kΩ.The results obtained can be used in the development of technological foundations for the formation of high-performance multilevel artificial synapses for elements of neuroelectronics and hardware neural networks.

关键词： artificial intelligence neuromorphic systems memristive cross bar resistive switching scanning probe microscopy titanium oxide

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Management of lateral pelvic lymph nodes in rectal cancer:is it time to reach an Agreement?

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World Journal of Clinical Oncology 2024年第4期15卷 472-477页

作者： Sigfredo e Romero-Zoghbi Fernando López-campos Felipe Couñago Department of Radiation Oncology GenesisCareTalavera de la Reina 45600ToledoSpain Department of Radiation Oncology Hospital Universitario Ramón Y CajalMadrid 28034Spain Department of Radiation Oncology GenesisCare-Hospital Universitario Vithas Madrid La MilagrosaMadrid 28010Spain

in this editorial,we proceed to comment on the article by Chua et al,addressing the management of metastatic lateral pelvic lymph nodes(mLLN)in stage ii/iii rectal cancer patients below the peritoneal *** treatment of this nodal area sparks significant controversy due to the strategic differences followed by eastern and Western physicians,albeit with a higher degree of convergence in recent *** dissection of lateral pelvic lymph nodes without neoadjuvant therapy is a standard practice in eastern *** contrast,in the West,preference leans towards opting for neoadjuvant therapy with chemoradiotherapy or radiotherapy,that would cover the treatment of this area without the need to add the dissection of these nodes to the total mesorectal *** the presence of high-risk nodal characteristics for mLLN related to radiological imaging and lack of response to neoadjuvant therapy,the risk of lateral local recurrence increases,suggesting the appropriate selection of strategies to reduce the risk of recurrence in each patient *** the heterogeneous and retrospective nature of studies addressing this area,an international consensus is necessary to approach this clinical scenario uniformly.

关键词： Rectal cancer Lateral pelvic lymph node metastases Pelvic lymph node dissection Total neoadjuvant therapy Selective management of the lateral pelvic nodes Prophylactic management of the lateral pelvic nodes Chemoradiotherapy Total mesorectal excision

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intracellular interactions in the Reproduction Control of introgressed Strains involving Species from Drosophila saltans Group(Sophophora Subgenus)with emphasis to the effect of Wolbachia infection

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Open Journal of Animal Sciences 2019年第3期9卷 324-340页

作者： Thais de Franca Patarro Hermione e.M.de campos Bicudo Departamento de Biologia Instituto de Biociencias Letras e Ciencias Exatas(Ibilce)Campus Sao Jose do Rio PretoUniversidade Estadual Paulista(Unesp)Sao Jose do Rio PretoBrasil

interspecific hybrids and constructed research models have provided infor-mation on intracellular interactions. We used two introgressed, chromosomally differentiated strains (H4 and H2) derived from F1 hybrids of crosses between D. prosaltans females and D. saltans males. in H4, the D. prosaltans chromosomes were eliminated. in H2, a mixture was maintained, preserving the entire genome of D. prosaltans (except the Y chromosome) and parts of the D. saltans genome. The iiR arm and a segment of chromosome iii were eliminated. A third strain, used for comparison, was a normal D. prosaltans strain (P). This study aimed primarily to analyze the effect on the reproductive char-acteristics productivity (number of progeny) and sex-ratio caused by Wolbachia infection in interaction with different chromosome constitutions. For this, infected and uninfected flies were used in intrastrain cross combinations. Firstly, we analyzed the productivity of intracrosses of uninfected parents, in each strain, in order to detect the effects of intracellular interactions, in flies carrying different chromosome constitutions and sharing a Wolbach-ia-free, D. prosaltans cytoplasm. Data indicated that the chromosome parts that were eliminated, in H2, carry the isolating genes that impair productivity in hybrids of the two species, and suggested the occurrence of a nuclear/nuclear interaction. The analysis of Wolbachia-infected flies showed that the three strains presented different responses, depending on the chromosome constitution. As to productivity, the infection was harmful in P strain, in H2 behaved as mutualistic, and, in H4, produced the effect cytoplasmic incompatibility. As to sex-ratio, intracrosses showed significant differences in P and H4 strains. These results, associated with the cytological characteristics of the strains, pointed to the fundamental importance of host chromosome constitution to define the interactive process host/Wolbachia, and showed the flexibility of the en

关键词： isolating Genes Harmful interaction Mutualistic interaction Cytoplasmic incompatibility of Wolbachia

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Hydrothermal Characteristics of Blended Cement Pastes Containing Silica Sand Using Cement Kiln Dust as an Activator

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Journal of Materials Science & Technology 2002年第5期18卷 474-478页

作者： S.A.Abo-el-enein F.i.el-Hosiny e.el-Shimy T.A.Osman Faculty of Sci. Ain Shams Univ. Abbassia-Cairo Egypt Building Res. Cent. Cairo P. O. Box 1770 Egypt

The hydrothermal reactivity of silica sand was studied using cement kiln dust (CKD) as an activator in addition to the Portland cement fraction of el-Karnak cement (a blend of ordinary Portland cement and ground sand). Autoclaved ei-Karnak cement pastes were studied at pressures of 0.507, 1.013 and 1.520 MPa of saturated steam with respect to their compressive strength, kinetics of hydrothermal reaction and the phase composition of the formed hydrates. The role of CKD in affecting the physicoche.i.a. and mechanical properties of ei-Karnak cement pastes was studied by autoclaving of several pastes containing 5, 7.5, 10 and 20% CKD at a pressure of 1.013 MPa of saturated steam. CKD was added either as a raw CKD (unwashed) or after washing with water (washed CKD). The results of these physicoche.i.a. studies obtained could be related as much as possible to the role of CKD (raw or washed) in affecting the hydrothermal reactivity of silica sand in ei-Karnak cement pastes.

关键词： Blended cement Silica Cement kiln dust Hydrothermal characteristics

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Changes in rainfall partitioning caused by the replacement of native dry forests of Lithraea molleoides by exotic plantations of Pinus elliottii in the dry Chaco mountain forests, central Argentina

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Journal of Arid Land 2020年第5期12卷 717-729页

作者： Samia S CORTÉS Juan i WHiTWORTH-HULSe eduardo L PiOVANO Diego e GURViCH Patricio N MAGLiANO Land Science Research Center(CiCTeRRA-CONiCeT)and National University of Córdoba Av.Vélez Sarsfield 1611X5016GCA CórdobaArgentina Multidisciplinary institute of Plant Biology National University of Córdoba and CONICETCC 495X5000JJC CórdobaArgentina environmental Study Group Institute of Applied Maths of San LuisNational University of San Luis and CONICETEjército de los Andes 950D5700HHW San LuisArgentina Department of Biology Faculty of ChemistryBiochemistry and PharmacyNational University of San LuisEjército de los Andes 950D5700HHW San LuisArgentina

The replacement of native dry forests by commercial(exotic)tree plantations could generate changes in rainfall partitioning,which further affects the water *** this study,we determined(i)the rainfall partitioning into interception,throughfall and stemflow,(ii)the role of rainfall event size on rainfall partitioning,(iii)the pH of water channelized as throughfall and stemflow,and(iv)the runoff in Lithraea molleoides(a native species)and Pinus elliottii(an exotic species)stands in the dry Chaco mountain forests,central *** average,interception,throughfall and stemflow accounted for 19.3%,79.5%and 1.2%of the gross rainfall in *** stand,and 32.6%,66.7%and 0.7%of the gross rainfall in *** stand,*** of interception,throughfall and stemflow presented positive linear relationships with the increment of rainfall event size for both tree species(Pin all cases).Percentages of interception,throughfall and stemflow were all related to the increment of rainfall event size,showing different *** increasing rainfall event size,interception exponentially decreased,throughfall asymptotically increased and stemflow linearly *** *** and *** stands presented significant differences in the pH values of water channelized as throughfall(6.3 vs.6.7,respectively;Pemflow(4.5 vs.5.8,respectively;Pied only 0.3%of the gross rainfall in *** stand and was zero in *** *** results showed that the native species *** presented 13.6%more water reaching the topsoil(i.e.,net rainfall;net rainfall=gross rainfall-interception-runoff)than the exotic species *** study improves our understanding of the effects of native vegetation replacement on the local water balance in the dry forest ecosystems.

关键词： drylands ecohydrology land use changes spatial heterogeneity water-limited environments

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Quantum-dot microlasers based on whispering gallery mode resonators

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Light(Science & Applications) 2021年第5期10卷 785-795页

作者： A.e.Zhukov N.V.Kryzhanovskaya e.l.Moiseev M.V.Maximov Laboratory of quantum optoelectronics National Research University Higher School of EconomicsKantemirovskaya 3ASt.Petersburg 194100Russia Nanophotonics laboratory Alferov UniversityKhlopina 8/3St.Petersburg 194021Russia

The subject of this paper is microlasers with the emission spectra determined by the whispering gallery *** to the total internal reflection of light on the sidewalls,a high Q-factor is achieved until the diameter is comparable to the *** light emission predominantly occurs in the plane of the structure,which facilitates the microlaser integration with other *** focus on microdisk lasers with various types of the in(Ga)As quantum dots(QDs).Deep localization of charge carriers in spatilly separated regions suppresses the lateral diffusion and makes it possible to overcome the unde.i.a.le effect of non-adiative recombination in deep ***,using conventional e.i.a.ial structures and relatively simple post-growth processing methods,it is possible to realize small microlasers capable of operating without temperature stabilization at elevated *** low sensitivity of QDs to e.i.a.ial and manufacturing defects allows fabricating microlasers using iiV heterostructures grown on silicon.

关键词： Quantum mode overcome

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effects of forest management on biomass stocks in Romanian beech forests

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Forest ecosystems 2019年第3期6卷 179-193页

作者： O.Bouriaud A.Don i.A.Janssens G.Marin e.-D.Schulze integrated Center for Research Development and Innovation in Advanced MaterialsNanotechnologiesand Distributed Systems for Fabrication and ControlStefan cel Mare University720229 SuceavaRomania National Forest inventory National Research Development Institute for Silviculture Voluntari Romania. vTi BraunschweigGermany Department of Biology University of AntwerpenUniversiteitsplein 12610 WilrijkBelgium Faculty of Silviculture and Forest engineering Transilvania University of BrasovStr. Sirul Beethovennr.1500123 BrasovRomania Max-Planck institute for Biogeochemistry PO Box 10016407701 JenaGermany

Background: Forest management aims at obtaining a sustainable production of wood to be harvested to generate products or energy. However, the quantitative influence of forest management and of removals by harvest on biomass stocks has rarely been analysed on a large scale based on measurements. Two hypotheses prevail: management induces a reduction of wood stocks due to cuttings, versus no impact because of increased growth of the remaining trees. Using data collected for 2840 permanent plots across Romania from the National Forest inventory representing^2.5 Mha, we have tested to what extent different management types and treatments can influence the biomass stock and productivity of beech forests, and attempt to quantify these effects both on the short and long terms. Three main types of beech forest management are implemented in Romania with specific objectives: intensive wood production in production forests, protection of ecosystem services (e.g. watersheds, avalanche protection) in protection forests, and protection of the forest and its biodiversity in protected forests. Production forests encompass two treatments differing according to the stand regeneration method: the age class rotation management and the group shelterwood management. Results: We show that forest management had little influence on the biomass stocks at a given stand age. The highest stocks at stand age 100 were observed in production forests (the most intensively managed forests). Consequences of early cuttings were very short-termed because the increase in tree growth rapidly compensated for tree cuttings. The cumulated biomass of production forests exceeded that of protected and protection forests. Regarding the treatment, the group shelterwood forests had a markedly higher production over a full rotation period. The total amount of deadwood was primarily driven by the amount of standing deadwood, and no management effect was detected. Conclusions: Given the relatively low-intensity mana

关键词： Forest management Forest productivity Biomass stocks National forest inventory

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