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MHD from a Microscopic concept and Onset of Turbulence in Hartmann Flow

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communications in Theoretical Physics 2010年第3期53卷 579-583页

作者： l.Jirkovsky l.Ma.Bo-ot c.M.chiang Department of Informatics and Geo-informatics Fakulta Zivotniho ProstrediUniversity of J.E. Purkyne National Institute of Physics University of the Philippines Department of Architecture National Cheng Kung University Taiwan college of Architecture University of the Philippines

We derive higher order magneto-hydrodynamic (MHD) equations from a microscopic picture using projection and perturbation formalism. In an application to Hartmann flow we find velocity profiles flattening towards the center at the onset of turbulence in hydrodynamic limit. comparison with the system under the effect of a uniform magnetic field yields difference in the onset of turbulence consistent with observations, showing that the presence of magnetic field inhibits onset of instability or turbulence. The laminar-turbulent transition is demonstrated in a phase transition plot of the development in time of the relative average velocities vs. Reynolds number showing a sharp increase of the relative average velocity at the transition point as determined by the critical Reynolds number.

关键词： projection techniques onset of turbulence MHD Hartmann flow

Effect of static annealing on superplastic behavior of a friction stir welded Ti-6Al-4V alloy joint and microstructural evolution during deformation

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Journal of Materials Science & Technology 2022年第35期130卷 112-123页

作者： c.l.Jia l.H.Wu P.Xue D.R.Ni B.l.Xiao Z.Y.Ma Shi-changxu Innovation center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Structural integration is one of the most critical developing directions in the modern aerospace field,in which large-scale complex components of Ti alloys are proposed to be fabricated via the method of welding + superplastic ***,the undesired strain localization appeared during superplastic deformation of the entire joint has largely hindered the development of this *** our study,a combination process of friction stir welding(FSW) + static annealing+ superplastic deformation was first time proposed to eliminate severe local *** achieve this result,a fully fine lamellar structure was obtained in the nugget zone(NZ) via FSW,which was totally different from the mill-annealed structure in the base material(BM).After annealing at 900℃ for 180 min,the BM and NZ then exhibited the similar elongation of> 500% and similar flow stress at 900 ℃,3 × 10^(-3)s^(-1),which was the precondition for achieving uniform superplastic deformation in the entire ***,the different microstructures in the BM and NZ tended to become the similar equiaxed structure after deformation,which was the result of different microstructural evolution mechanisms in the NZ and *** the NZ,there was a static and dynamic spheroidization of the fully lamellar structure during the process,which could largely reduce the flow softening of the fully lamellar *** the BM,a new view of "langdon-cRSS theory"(cRSS,critical resolved shear stress) was proposed to describe the fragmentation of the coarse equiaxed structure,which established the relationship between grain boundary sliding and intragranular deformation during deformation.

关键词： Friction stir welding Titanium alloys Superplasticity Static annealing Microstructure

comments on the release laboratory Manual for the Human Semen of the 5th edition of the WHO Examination and Processing of

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Asian Journal of Andrology 2010年第1期12卷 59-63页

作者： W. c. l. Ford Obstetrics ＆ Gynaecology Unit Clinical Science at South Bristol University of Bristol St Michael＇s Hospital Bristol BS28EG UK

The authors of the World Health Organization Semen Analysis Manual are to be congratulated on producing a new edition; it is an essential tool to disseminate good practice in andrology. However, the tests described have poor prognostic power to predict a man＇s fertility and show little about the underlying causes of sub-fertility. This commentary urges a revival of research into the diagnosis of male fertility. It suggests that fertility should be regarded as a continuum and that the artificial binary division between fertile and infertile should be abandoned. Models to predict a sub-fertile couple＇s chance of conception in a year should be developed on the basis of prospective data. These models would allow for sophisticated decision making about management. The future lies in the identification of tests to detect underlying pathologies open to specific treatment. leads such as oxidative stress, defects in the intracellular regulation and the developing field ofproteomics should be explored.

关键词： diagnosis male infertility oxidative stress predictive value of tests sperm count

local heroes or villains:tissue-resident memory T cells in human health and disease

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cellular & Molecular Immunology 2020年第2期17卷 113-122页

作者： S.c.Sasson c.l.Gordon S.N.christo P.Klenerman l.K.Mackay Translational Gastroenterology Unit Nuffield Department of MedicineUniversity of OxfordOxfordUK Department of Microbiology and Immunology Peter Doherty Institute for Infection and ImmunityUniversity of MelbourneMelbourneVICAustralia Department of Infectious Diseases Austin HealthMelbourneVICAustralia Peter Medawar Building for Pathogen Research University of OxfordOxfordUK

Tissue-resident memory T(T_(RM))cells are increasingly associated with the outcomes of health and disease.T_(RM) cells can mediate local immune protection against infections and cancer,which has led to interest in T_(RM) cells as targets for vaccination and ***,these cells have also been implicated in mediating detrimental pro-inflammatory responses in autoimmune skin diseases such as psoriasis,alopecia areata,and ***,we summarize the biology of T_(RM) cells established in animal models and in translational human *** review the beneficial effects of T_(RM) cells in mediating protective responses against infection and cancer and the adverse role of T_(RM) cells in driving pathology in autoimmunity.A further understanding of the breadth and mechanisms of T_(RM) cell activity is essential for the safe design of strategies that manipulate T_(RM) cells,such that protective responses can be enhanced without unwanted tissue damage,and pathogenic T_(RM) cells can be eliminated without losing local immunity.

关键词： human T cells tissue-resident memory immunity

Effects of noisy quantum channels on one-qubit rotation gate

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Science china(Physics,Mechanics & Astronomy) 2012年第5期55卷 808-814页

作者： XU GuoFu Kwek l.c TONG DianMin Department of Physics Shandong UniversityJinan 250100China center for Quantum Technologies National University of SingaporeScience Drive 2 Singapore 117543Singapore

We investigate the effects of noisy quantum channels on the entanglement of cluster states and one way quantum computational *** take a basic model,the rotational gate about x axis based on the cluster state,in order to get the most essential effects of the paradigmatic noisy quantum *** entanglement of cluster states in the noisy channels and the fidelity between the rotated state without noisy channel and that with noisy channel are calculated.

关键词： one-way quantum computation entanglement decoherence

Estrogen enhances the functions of cD4^(+)cD25^(+)Foxp3^(+) regulatory T cells that suppress osteoclast differentiation and bone resorption in vitro

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cellular & Molecular Immunology 2011年第1期8卷 50-58页

作者： cY luo l Wang c Sun DJ li laboratory for Reproductive Immunology Hospital and Institute of Obstetrics and GynecologyFudan University Shanghai Medical CollegeShanghaiChina Jiangsu Province Hospital the First Affiliated Hospital with Nanjing Medical UniversityNanjingChina Department of Obstetrics and Gynecology Affiliated HospitalHainan Medical CollegeHaikouChina

cross-talk has been shown to occur between the immune system and bone metabolism *** the present study,we investigated the impact of cD4^(+)cD25^(+)Foxp3^(+) regulatory T(Treg)cells on osteoclastogenesis and bone *** cells that were isolated and purified from peripheral blood mononuclear cells(PBMcs)of healthy adults inhibited both the differentiation of osteoclasts(Ocs)from human embryo bone marrow cells(BMcs)and the pit formation in a dose-dependent *** cell cocultures,the production levels of both interleukin-10(Il-10)and transforming growth factor-beta 1(TGF-β1)were proportionally upregulated as the ratio of Treg cells to BMcs was increased,and the inhibition of Oc differentiation and bone resorption by Treg cells was completely reversed by anti-Il-10 and anti-TGF-β1 *** of BMc and Treg cell cocultures with 17β-estradiol(E2)at concentrations between 10^(-7) and 10^(-9) mol/l suppressed Oc differentiation and bone resorption more efficiently than it did in cultures of BMcs alone;this enhanced suppression occurred via the stimulation of Treg cell Il-10 and TGF-b1 *** data suggest that Treg cells suppress Oc differentiation and bone resorption by secreting Il-10 and TGF-β1.E2 enhances the suppressive effects of Treg cells on Oc differentiation and bone resorption by stimulating Il-10 and TGF-β1 secretion from these ***,Treg cell-derived Il-10 and TGF-b1 are likely involved in the regulation of E2 on bone metabolism and represent potential therapeutic targets for the treatment of postmenopausal osteoporosis(PMO).

关键词： bone resorption osteoclast PMO regulatory T cells

THE EFFEcT OF BORON AND cARBON ADDITION ON WElDABIlITY OF DS TMS-75 SUPERAllOY

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Acta Metallurgica Sinica(English letters) 2005年第1期18卷 24-32页

作者： M.c. chaturvedi N.l. Richards Department of Mechanical and Industrial Engineering University of Manitoba Winnipeg Manitoba R3T 5V6 CanadaDepartment of Mechanical and Industrial Engineering University of Manitoba Winnipeg Manitoba R3T 5V6 Canada

Four alloys TMS-75 (Base), Base+B, Base+c and TMD-103 (Base+B+c) with varying levels of B, c were directionally solidified (DS), and their weldability was investigated by bead-on-plate electron beam welding. It was found that cracking occurred in the weld-metal, as well as in the heat affected zone (HAZ). Both γ/γ' and/or γ/carbide eutectic contributed to the weld-metal cracking, and the γ/γ' eutectic was found to be mainly responsible for cracking in HAZ. However, constitutional liquation of carbides seems to have made some contribution also. The B addition had a detrimental effect on HAZ cracking susceptibility, while c addition improved it appreciably even in the presence of B. In addition, no obvious differences were observed in cracking susceptibility of weld-metal in the four alloys. The cracking modes and mechanisms underlying the effect of B and c addition on weldability could be explained on the basis of microstructures of the four alloys.

关键词： Ni-based superalloy low melting point constituents liquation cracking

How artificial intelligence uses to achieve the agriculture sustainability:Systematic review

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Artificial Intelligence in Agriculture 2023年第2期8卷 46-59页

作者： Vilani Sachithra l.D.c.S.Subhashini University of Sri Jayewardenepura Sri Lanka

The generation of food production that meets the rising demand for food and ecosystem security is a bigchallenge. With the development of Artificial Intelligence (AI) models, there is a growing need to use them toachieve sustainable agriculture. The continuous enhancement of AI in agriculture, researchers have proposedmany models in agriculture functions such as prediction,weed control, resource management, advance care ofcrops, and so on. This article evaluates on a systematic review of AI models in agriculture functions. It also reviewshow AI models are used in identified sustainable objectives. Through this extensive review, this paper discussesconsiderations and limitations for building the next generation of sustainable agriculture using AI.

关键词： AI Agriculture Sustainability Review Robotics Deep learning

Response of an old landslide to reservoir filling: A case history

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Science china(Technological Sciences) 2005年第z1期48卷 27-32页

作者： l.G. Tham c.F. lee Department of civil Engineering University of Hong Kong Hong Kong China

Unfavorable hydrodynamic evolution is considered as the major cause leading to reservoir slope instability and is often modeled by numerical method. However, this simulation is seldom checked by systematic field instrumentation. Taking the opportunity of filling the Three Gorges Reservoir, a system was established in Xietan landslide to monitor reservoir water level, subground water level, seepage pressure, rainfall and deformation, etc. The monitored data during reservoir filling shows that: (1) The water level rise in the bank lags behind the reservoir filling and the lag time depends on the bank permeability; (2) rainfall-induced subground water rise and its lag time is closely correlated to hourly rainfall, indicating that it is not feasible or sufficient to use daily rainfall for analysis; (3) the effect of inverse seepage during reservoir filling on stability is ephemeral and reservoir filling is the major cause leading to bank instability.

关键词： reservoir filling, old landslide, monitoring system, water level, deformation.