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NUMErICAL STUDIES OF A CLASS OF COMpOSITE prECONDITIONErS

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Journal of Computational Mathematics 2014年第2期32卷 136-151页

作者： Qiang Niu Michael ng Mathematics and physics Centre Xi'an Jiaotong-Liverpool University Suzhou 215123 China Department of Mathematics Hong Kong Baptist University Kowloon Tong Hong Kong

In this paper, we study a composite preconditioner that combines the modified tangential frequency filter.ng decomposition with the ILU（O） factorization. Spectral property of the composite preconditioner is examined by the approach of Fourier analysis. We illustrate that condition number of the preconditioned matrix by the composite preconditioner is asymptotically bounded by O（hp -2/3） on a standard model problem. performance of the composite preconditioner is compared with other preconditioners on several problems arising from the discretization of pDEs with discontinuous coefficients. Numerical results show that performance of the proposed composite preconditioner is superior to other relative preconditioners.

关键词： preconditioner ILU Tangential frequency filter.ng decomposition GMrES.

A promiscuous interaction of SArS-CoV-2 with bacterial products

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Journal of Molecular Cell Biology 2020年第12期12卷 914-915页

作者： Guillaume Carissimo Lisa F.p.ng A*STAr Infectious Disease laboratories(A*ID Labs) Agency for ScienceTechnology and ResearchImmunosSingapore 138648Singapore Singapore Immunology Network(SlgN) Agency for ScienceTechnology and ResearchlmmunosSingapore 138648Singapore Institute of Infection Veterinary and Ecological SciencesUniversity of LiverpoolLiverpool L73EAUK

SArS-CoV-2 is the virus responsible for COVID-19 disease,and since its emergence it has spread globally with the number of total cases in the tens of ***-19 presents with varied clinical manifestations that r.nge from asymptomatic disease to severe respiratory disease(pneumonia)with multiple organ failure and *** risk factors have been associated with severe COVID-19 disease such as age,gender,diabetes,cardiovascular disease,treat-ments,and comorbidities that affect the immune system(Harrison et al,2020).

关键词： cardiovascular respiratory clinical

Lowered testosterone in male obesity： mechanisms, morbidity and management

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Asian Journal of Andrology 2014年第2期16卷 223-231,I0008页

作者： Mark ng Tang Fui Department of Medicine Austin Health University of Melbourne Melbourne Department of Endocrinology Austin Health Melbourne Victoria Australia

With increasing modernization and urbanization of Asia, much of the future focus of the obesity epidemic will be in the Asian region. Low testosterone levels are frequently encountered in obese men who do not otherwise have a recognizable hypothalamic-pituitary-testicular （HpT） axis pathology. Moderate obesity predominantly decreases total testosterone due to insulin resistance-associated reductions in sex hormone binding globulin. More severe obesity is additionally associated with reductions in free testosterone levels due to suppression of the HpT axis. Low testosterone by itself leads to increasing adiposity, creating a self-perpetuating cycle of metabolic complications. Obesity-associated hypotestosteronemia is a functional, non-permanent state, which can be reversible, but this requires substantial weight loss. While testosterone treatment can lead to moderate reductions in fat mass, obesity by itself, in the absence of symptomatic androgen deficiency, is not an established indication for testosterone therapy. Testosterone therapy may lead to a worsening of untreated sleep apnea and compromise fertility. Whether testosterone therapy augments diet- and exercise-induced weight loss requires evaluation in adequately designed randomized controlled clinical trials.

关键词： androgens hypogonadism obesity testosterone weight loss

Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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Matter and radiation at Extremes 2024年第2期9卷 12-25页

作者： J.-r.Marquès L.Lancia p.Loiseau p.Forestier-Colleoni M.Tarisien E.Atukpor V.Bagnoud C.Brabetz F.Consoli J.Domange F.Hannachi p.Nicolaï M.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance Universitéparis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear Safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance Universitéparis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailor.ng by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailor.ng on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailor.ng,by tailor.ng only the entrance side of the picosecond laser,and by tailor.ng both sides of the gas *** tailor.ng,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailor.ng both sides of the gas *** parameters are in good agreement with those required for CSA.

关键词： acceleration hydrodynamic collision

On compact splitting complex submanifolds of quotients of bounded symmetric domains

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Science China Mathematics 2017年第6期60卷 1057-1076页

作者： MOK ngaiming ng SuiChung Department of Mathematics The University of Hong Kong Department of Mathematics Shanghai Key Laboratory of PMMPEast China Normal University

We study compact complex submanifolds S of quotient manifolds X =Ω/F of irreducible bounded symmetric domains by torsion free discrete lattices of automorphisms, and we are interested in the characterization of the totally geodesic submanifolds among compact splitting complex submanifolds S C X, i.e., under the assumption that the tangent sequence over S splits holomorphically. We prove results of two types. The first type of results concerns S C X which are characteristic complex submanifolds, i.e., embedding Ω as an open subset of its compact dual manifold M by means of the Borel embedding, the non-zero （1, 0）-vectors tangent to S lift under a local inverse of the universal cover.ng map π → X to minimal rational tangents of M. We prove that a compact characteristic complex submanifold S C X is necessarily totally geodesic whenever S is a splitting complex submanifold. Our proof generalizes the case of the characterization of totally geodesic complex submanifolds of quotients of the complex unit ball B^n obtained by Mok （2005）. The proof given here is however new and it is based on a monotonic property of curvatures of Hermitian holomorphic vector subbundles of Hermitian holomorphic vector bundles and on exploiting the splitting of the tangent sequence to identify the holomorphic tangent bundle Ts as a quotient bundle rather than as a subbundle of the restriction of the holomorphic tangent bundle Tx to S. The second type of results concerns characterization of total geodesic submanifolds among compact splitting complex submanifolds S C X deduced from the results of Aubin （1978） and Yau （1978） which imply the existence of Kahler-Einstein metrics on S C X. We prove that compact s- plitting complex submanifolds S C X of sufticiently large dimension （depending on ） are necessarily totally geodesic. The proof relies on the Hermitian-Einstein property of holomorphic vector bundles associated to TS, which implies that endomorphisms of such bundles are parallel, and the co

关键词： bounded symmetric domains tangent sequence splitting complex submanifolds varieties of minimal rational tangents K/ihler-Einstein metrics

Evaluation of Mechanical properties and Surface Quality of Wood from Bosnia and Herzegovina Exposed to Outdoor Conditions

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Journal of renewable Materials 2024年第8期12卷 1417-1431页

作者： Hasanagić r. Šljivo U. Fathi L. Gautam p. Bahmani M. Humar M. Department of Wood Science and Technology Faculty of Technical Engineering University of Bihać Bihać 77000 Bosnia and Herzegovina Department of Wood and Furniture Industry Engineer.ng Faculty of Resources and Earth Science Shahrekord University Shahrekord 64165478 Iran Department of Botany Institute of Science Banaras Hindu University Uttar Pradesh Varanasi 221005 India Biotechnical Faculty Department of Wood Science University of Ljubljana Ljubljana 1501 Slovenia

This study investigated the mechanical properties of beech (Fagus sylvatica L.) and fir (Abies alba) wood from Bosnia and Herzegovina under outdoor exposure. Samples were exposed for 3-month exposure to assess bending str.ngth, color changes, and surface quality. results showed outdoor exposure negatively affected mechanical properties, particularly in samples with extended finger joints, causing significant surface cracks in uncoated sam-ples. Beech wood exhibited notable color changes under exposure, with approximately 50% darkening without coating compared to 25% under covered conditions. Coated samples displayed minimal color changes, affirming the efficacy of surface treatment. Fir wood exhibited a roughness of 8.264 μm, while beechwood average roughness increased from 6.767 to 13.916 μm after exposure, with micro-pore development affecting water perfor-mance. Microscopic analysis identified prevalent fungal colonies, including penicillium, Aureobasidium, Sclerophoma, and Chaetomium, underscor.ng their role in organic matter decomposition. This study highlights the importance of wood exposure and treatment selection for various applications. © 2024 The Authors.

关键词： cracks Mechanical properties outdoor conditions wood species

Malinger.ng or simulation in ophthalmology-visual acuity

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International Journal of Ophthalmology(English edition) 2011年第5期4卷 558-566页

作者： Ali Ihsan Incesu Güngr Sobaci S.B Konya Egitim-Arastirma Hastanesi Gz Klinigi GATA Gz Klinigi

Simulation can be defined as malinger.ng, or sometimes functional visual loss (FVL). It manifests as either simulating an ophthalmic disease (positive simulation), or denial of ophthalmic disease (negative simulation). Conscious behavior and compensation or indemnity claims are prominent features of simulation. Since some authors suggest that this is a manifestation of underlying psychopathology, even conversion is included in this context. In today's world, every ophthalmologist can face with simulation of ophthalmic disease or disorder. In case of simulation suspect, the physician's responsibility is to prove the simulation consider.ng the disease/disorder first, and simulation as an exclusion. In simulation examinations, the physician should be firm and smart to select appropriate test(s) to convince not only the subject, but also the judge in case of indemnity or compensation trials. Almost all ophthalmic sensory and motor functions including visual acuity, visual field, color vision and night vision can be the subject of simulation. Examiner must be skillful in selecting the most appropriate test. Apart from those in the literature, we included all kinds of simulation in ophthalmology. In addition, simulation examination techniques, such as, use of OCT (optical coherence tomography), frequency doubling perimetry (FDp), and modified polarization tests were also included. In this review, we made a thorough literature search, and added our experiences to give the readers up-to-date information on malinger.ng or simulation in ophthalmology.

关键词： malinger.ng simulation conversion hysteria

A dual-electrolyte system for photoelectrochemical hydrogen generation using CuInS_2-In_2O_3-TiO_2 nanotube array thin film

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Science China Materials 2018年第6期61卷 895-904页

作者： Charlene ng Jung-Ho Yun Hui Ling Tan Hao Wu rose Amal Yun Hau ng particles and Catalysis research Group School of Chemical Engineering The University of New South Wales

The utilization of Na2S/Na2SO3 mixture as the electrolyte solution to stabilize sulfide anode in a photoelectrochemical cell for hydrogen evolution generally compromises the current-to-hydrogen efficiency（ηcurrent） of the system. Here, the employment of a dual-electrolyte system,that is, Na2S/Na2SO3 mixture and p H-neutral Na2SO4 as the respective electrolyte solutions in the anode and cathode chambers of a water splitting cell is demonstrated to suppress the photocorrosion of CuInS2-In2O3-TiO2 nanotube（CISIn2O3-TNT） heterostructure, while simultaneously boosts theηcurrent. Although n-type CIS and In2O3 nanoparticles can be easily formed on TNT array via facile pulse-assisted electrodeposition method, conformal deposition of the nanoparticles homogeneously on the nanotubes wall with preservation of the TNT hollow structure is shown to be essential for achieving efficient charge generation and separation within the heterostructure. In comparison to Na2S/Na2SO3 solution as the sole electrolyte in both the anode and cathode chambers, introduction of dual electrolyte is shown to not only enhance the photostability of the CIS-In2O3-TNT anode, but also lead to near-unity ηcurrentas opposed to the merely 20% ηcurrentof the single-electrolyte system.

关键词： dual-electrolyte hydrogen generation photoelectrochemical TiO2 nanotubes CuInS2

Species delimitation in the White-faced Cuckoo-dove(Turacoena manadensis) based on bioacoustic data

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Chinese Birds 2016年第1期7卷 40-47页

作者： Nathaniel S.r.ng Frank E.rheindt Department of Biological Sciences National University of Singapore

Background: The White-faced Cuckoo-dove(Turacoena manadensis) is a poorly-known Wallacean endemic with a limited distribution on Sulawesi and its satellites, including the Togian, Banggai and Sula archipelagoes. In 1900, populations from the Sula archipelago were awarded subspecies status T. manadensis sulaensis based on smaller size and minor differences in plumage; however, this distinction has not been corroborated subsequently, and T. manadensis is considered by most modern sources to be monotypic across its ***: We conducted vocal analysis of the cuckoo-doves' main song using recordings collected from across the taxon's natural r.nge. Descriptive information on the songs was obtained from the recordings using bioacoustic analysis software, after which several statistical methods were used to investigate differences in vocalizations among ***: We report deep bioacoustic divergences in vocal trait pattern from across the cuckoo-doves' r.nge, with birds from peleng and Taliabu in the east having a different vocal trait pattern from birds from Sulawesi, Buton, and Togian in the west. These patterns agree with changes in landmass that accompanied the sea level fluctuations caused by pleistocene glacial cycles, and indicate that eastern and western cuckoo-dove populations are at the level of different biological ***: We propose that the eastern taxon be elevated to species level as T. sulaensis. Given the rampant degree of habitat destruction in its limited r.nge, this taxonomic change will have important implications on the conservation status of T. sulaensis.

关键词： Wallacea Sulawesi peleng Taliabu Buton pleistocene Island biogeography