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Inscribing the core memories of killers

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Cellular & Molecular Immunology 2019年第2期16卷 104-105页

作者： Sarah j.Dulson Laurie E.Harrington Allan j.Zajac Department of Cell Developmentaland Integrative BiologyUniversity of Alabama at BirminghamBirminghamAL 35294United States Department of Microbiology University of Alabama at BirminghamBirminghamAL 35294United States

Recent studies on natural killer(NK)cells have challenged the dogma that immunological memory is a phenomenon restricted to the adaptive immune *** interactions between the NK cell receptor Ly49H and the murine cytomegalovirus virus(MCMV)-encoded glycoprotein m157 result in selective expansion of the Ly49H+NK cell subpopulation and the establishment of a long-lived memory-like population.1–3 Further,memory NK cells show augmented IFNγresponses,and transfer of the memory population into naive mice confers enhanced protection against infection-induced mortality.1 These observations along with cytotoxicity and cytokine secretion functions that overlap with CD8 T cells have led to the description of NK cells as a bridge between the innate and adaptive immune systems.

关键词： killer mortality cytotoxicity

Mechanical properties and deformation mechanisms of Ti-3Al-5Mo-4.5V alloy with varied β phase stability

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作者： p.j·普列托

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journal of Materials Science & Technology 2018年第12期34卷 2507-2514页

作者： Q.Xue Y.j.Ma j.F.Lei R.Yang C.Wang Institute of Metal Research Chinese Academy of Sciences School of Metallurgy Northeastern University

Evolution of deformation mechanisms and mechanical properties of Ti-3Al-5Mo-4.5V alloy with different β phase stability have been systematically investigated. β phase stability alteration is achieved through quenching temperature variation from dual α+β field(700℃) to single β field(880℃). Tensile tests at ambient temperature show that apparent yield strength of the alloy experiences an abrupt decrease followed by a significant increase from 700℃ to 880℃. Work hardening behavior is characterized by transition from the initial two-regime feature to the three-stage outlook. Concurrently, the maximum working hardening rate drops from 14000 Mpa to 3000 Mpa, which is concurrent with the shrinking volume fraction of primary a phase. Detailed discussion about the relationship between deformation mechanisms and β phase stability has been outlined.

关键词： Dual-phase titanium alloy β phase stability Work hardening behavior Deformation mechanisms

Evolution of microstructure and phase composition of Ti-3Al-5Mo-4.5V alloy with varied β phase stability

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journal of Materials Science & Technology 2018年第12期34卷 2325-2330页

作者： Q.Xue Y.j.Ma j.F.Lei R.Yang C.Wang School of Metallurgy Northeastern University Institute of Metal Research Chinese Academy of Sciences

The microstructure evolution and phase composition of an α+β titanium alloy, Ti-3Al-5Mo-4.5V(wt.%),have been investigated. Electron probe micro analysis(EpMA) quantitative results manifest that the stability of β phase decreases with increasing quenching temperature, which is influenced by the significant variation of β-stabilizing elements concentration. Detailed microstructure analysis shows that the β→ωphase transformation does occur when quenching at 750℃ and 800 ℃. The ω-reflections change from incommensurate ω-spots(750 ℃) to ideal ω-spots(800 ℃) as the β stability of the alloy decreases. Further the decrease of β phase stability encourages the formation of athermal α " martensite, which has the following orientation relationships: [111]β//[110]α",[100]p//[100]α " and [-110]p//[00-1]α" with respect to the β matrix.

关键词： Dual-phase titanium alloy β phase stability ω phase α" martensite Microstructure

Real-time forecasts of the COVID-19 epidemic in China from February 5th to February 24th,2020

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Infectious Disease Modelling 2020年第1期5卷 256-263页

作者： K.Roosa Y.Lee R.Luo A.Kirpich R.Rothenberg j.M.Hyman p.Yan G.Chowell Department of population Health Sciences School of Public HealthGeorgia State UniversityAtlantaGAUSA Department of Mathematics Center for Computational ScienceTulane UniversityNew OrleansLAUSA Infectious Disease prevention and Control Branch Public Health Agency of CanadaOttawaCanada

The initial cluster of severe pneumonia cases that triggered the COVID-19 epidemic was identified inWuhan,China in December *** early cases of the disease were linked to a wet market,human-to-human transmission has driven the rapid spread of the virus throughout *** Chinese government has implemented containment strategies of city-wide lockdowns,screening at airports and train stations,and isolation of suspected patients;however,the cumulative case count keeps growing every *** ongoing outbreak presents a challenge for modelers,as limited data are available on the early growth trajectory,and the epidemiological characteristics of the novel coronavirus are yet to be fully *** use phenomenological models that have been validated during previous outbreaks to generate and assess short-term forecasts of the cumulative number of confirmed reported cases in Hubei province,the epicenter of the epidemic,and for the overall trajectory in China,excluding the province of *** collect daily reported cumulative confirmed cases for the 2019-nCoV outbreak for each Chinese province from the National Health Commission of ***,we provide 5,10,and 15 day forecasts for five consecutive days,February 5th through February 9th,with quantified uncertainty based on a generalized logistic growth model,the Richards growth model,and a sub-epidemic wave *** most recent forecasts reported here,based on data up until February 9,2020,largely agree across the three models presented and suggest an average range of 7409e7496 additional confirmed cases in Hubei and 1128e1929 additional cases in other provinces within the next five *** also predict an average total cumulative case count between 37,415 and 38,028 in Hubei and 11,588e13,499 in other provinces by February 24,*** estimates and uncertainty bounds for both Hubei and other provinces have remained relatively stable in the last three reporting dates(February 7th e 9th).We also observe that

关键词： COVID-19 Coronavirus China Real-time forecasts phenomenological models

EVOLUTION OF NACRE:A NEW EVIDENCE FOR CLOSE pHYLOGENETIC RELATIONSHIp OF CLASSES CEpHALOpODA AND GASTROpODA

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EVOLUTION OF NACRE:A NEW EVIDENCE FOR CLOSE PHYLOGENETIC REL...

A STUDY OF THE ONSET OF KINK BAND

第二届国际古生物学大会

作者： j.FRYDA M.RIEDER W.WEITSCHAT p.TYCOVA j.HALODA Czech Geological Survey Klarov 3/13111821 PragueCzech Republic Technicka Univerzita Ostrava Czech Republic Universitt Hamburg Germany Czech Geological Survey Czech Republic

On-going study of crystallographic textures and microstructures of nacre (mother of pearl) has provided new data of pivotal value for molluscan phylogeny. Nacre is considered to be the simplest of molluscan shell structures and it has been recorded in some members of the classes Gastropoda, Cephalopoda, Bivalvia, and Monoplacophora. Its sharing by different molluscan classes has been used for its interpretation as a plesiomorphic shell structure in some evolution-

关键词： Mollusca evolution nacre crystallographic textures

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Acta Mechanica Solida Sinica 1995年第3期8卷 189-201页

作者： GAO, j LIN, XL SHANDONG pOLYTECH UNIV JINANPEOPLES R CHINA

This paper suggests the asymmetric-plastic theory of crystalline solids concerning the plastic rotation of crystal. The deformation of crystalline solids undergoes three microprocesses, lattice distortion, slip over active crystallographic planes and the rotation- of the crystal. In the asymmetric-plastic theory of crystal suggested, the corotational rates of symmetric Cauchy stress and moment stress correspond to the rates of elastic strain and the gradient of the rotational rate of the crystal respectively. The Schmid yield condition and prager's consistency condition incorporating antisymmetric stress are formulated. Then the asymmetric-plastic model of crystalline solids is applied for the investigation of the onset of kink band by a standard stability analysis. The orientation of the kink band is perpendicular to the primary slip system. The width of the kink band is the function of the ''characteristic length'' of the microstructure of metal materials.

关键词： KINK BAND pLASTIC ROTATION OF CRYSTAL

Evaluation of Landsat 7 ETM＋ Data for Spectral Discrimination and Classification of Sugarcane Varieties in Colombia

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journal of Agricultural Science and Technology(B) 2011年第1期1卷 101-107页

作者： p. j. Murillo-Sandoval j. C. Carbonell-Gonzalez C. A. Osorio-Murillo Colombian Sugarcane Research Center CENICANA A.A 9138 Call Colombia Institute for Geoinformatics （IFGI） University of Munster Weseler Strasse 253 Muenster D 48151 Germany

An On-line Galvanic Cell Generated Electrochemiluminescence and Flow Injection Determination of Calcium in Milk and Vegetable

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Chinese Chemical Letters 2003年第6期14卷 599-602页

作者： Luo L.R. Lü j.G. Zhang Z.j. Department of Chemistry Shaanxi Normal University Xi'an 710062 China

An on-line Ag/Al galvanic cell is investigated and employed to generate electrochemiluminescence (ECL). The potential of the galvanic cell could be adjusted by varying the components of flow reagent. The cell performed perfect capability of supplying a stable potential for ECL generation. Based on the weak ECL of calcein blue could be greatly sensitized by the presence of calcium in alkaline solution, calcium contents in milk samples and in cabbage were assayed and the results were compared with those from ICp-AES method.

关键词： On-line galvanic cell electrochemiluminescence calcium.