8,445 research outputs found
Direct and inverse measurement of thin films magnetostriction
Two techniques of measurements of thin film magnetostriction are compared:
direct, when changes of the substrate curvature caused by the film
magnetization are controlled, and inverse ("indirect"), when the modification
of the magnetic anisotropy induced by the substrate deformation (usually
bending) is measured. We demonstrate how both the elastic strength of the
substrate and the effective magneto-mechanical coupling between the substrate
deformation and magnetic anisotropy of the film depend on different conditions
of bending. Equations to be used for magnetostriction value determination in
typical cases are given and critical parameters for the corresponding
approximations are identified.Comment: 13 pages, 10 figures, 1 table, submitted to JMM
Multi-block polyurethanes via RAFT end-group switching and their characterization by advanced hyphenated techniques
The detailed characterization of poly(styrene)-b-poly(tetrahydrofuran) (pS-b-pTHF) multiblock copolymers (17800 g mol(-1) <= M-n <= 46800 g mol(-1)) generated via urethane linkages is presented. The synthesis of the block copolymers is enabled via a mechanistic switch of the thiocarbonyl thio end group of a poly(styrene) to dihydroxyl terminated polymers that subsequently react with a diisocyanate terminated polytetrahydrofuran based prepolymer to form multiblock copolymer structures. The characterization of the multiblock copolymers and their substructures includes size exclusion chromatography (SEC), liquid chromatography at critical conditions (LCCC), nuclear magnetic resonance (NMR), and infrared (IR) spectroscopy as well as matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. To obtain even further details of the polymer size and its composition, SEC with triple detection as well as newly developed SEC coupled online to IR spectroscopy was carried out. The quantification of the average block fractions via online SEC-IR (41-61 mol % pTHF) is in very good agreement with the results obtained via NMR spectroscopy (39-66 mol % pTHF)
Using Heavy Quark Spin Symmetry in Semileptonic Decays
The form factors parameterizing the B_c semileptonic matrix elements can be
related to a few invariant functions if the decoupling of the spin of the heavy
quarks in B_c and in the mesons produced in the semileptonic decays is
exploited. We compute the form factors as overlap integral of the meson
wave-functions obtained using a QCD relativistic potential model, and give
predictions for semileptonic and non-leptonic B_c decay modes. We also discuss
possible experimental tests of the heavy quark spin symmetry in B_c decays.Comment: RevTex, 22 pages, 2 figure
Ціноутворення земель техногенного походження як чинник формування рівня їх споживчих властивостей
Визначено засади ціноутворення як головного чинника обгрунтування рівня відтворення екологічної та господарської цінності земель техногенного походження, встановлено вплив грошової оцінки на формування їх цільового споживчого ринку, представлено принципи поєднання екологічних та економічних складових оцінки рекультивованого ґрунту.Определены основы ценообразования как главного фактора обоснования уровня восстановления экологической и хозяйственной ценности земель техногенного происхождения, определено влияние денежной оценки на формирование их целевого потребительского рынка, представлены принципы объединения экологических и экономических составляющих оценки рекультивированного грунта.Defined pricing principles as the main factor of level playing ground environmental and economic values of land anthropogenic origin, the effect of monetary valuation of forming their target consumer market, representing a combination of ecological principles and economic evaluation of reclaimed soil constituents
Optical nanofibers and spectroscopy
We review our recent progress in the production and characterization of
tapered optical fibers with a sub-wavelength diameter waist. Such fibers
exhibit a pronounced evanescent field and are therefore a useful tool for
highly sensitive evanescent wave spectroscopy of adsorbates on the fiber waist
or of the medium surrounding. We use a carefully designed flame pulling process
that allows us to realize preset fiber diameter profiles. In order to determine
the waist diameter and to verify the fiber profile, we employ scanning electron
microscope measurements and a novel accurate in situ optical method based on
harmonic generation. We use our fibers for linear and non-linear absorption and
fluorescence spectroscopy of surface-adsorbed organic molecules and investigate
their agglomeration dynamics. Furthermore, we apply our spectroscopic method to
quantum dots on the surface of the fiber waist and to caesium vapor surrounding
the fiber. Finally, towards dispersive measurements, we present our first
results on building and testing a single-fiber bi-modal interferometer.Comment: 13 pages, 18 figures. Accepted for publication in Applied Physics B.
Changes according to referee suggestions: changed title, clarification of
some points in the text, added references, replacement of Figure 13
The Flagella of an Atypical Enteropathogenic Escherichia coli Strain Are Required for Efficient Interaction with and Stimulation of Interleukin-8 Production by Enterocytes in Vitro
The ability of some typical enteropathogenic Escherichia coli (EPEC) strains to adhere to, invade, and increase interleukin-8 (IL-8) production in intestinal epithelial cells in vitro has been demonstrated. However, few studies regarding these aspects have been performed with atypical EPEC (aEPEC) strains, which are emerging enteropathogens in Brazil. in this study, we evaluated a selected aEPEC strain (1711-4) of serotype O51:H40, the most prevalent aEPEC serotype in Brazil, in regard to its ability to adhere to and invade Caco-2 and T84 cells and to elicit IL-8 production in Caco-2 cells. the role of flagella in aEPEC 1711-4 adhesion, invasion, and IL-8 production was investigated by performing the same experiments with an isogenic aEPEC mutant unable to produce flagellin (FliC), the flagellum protein subunit. We demonstrated that this mutant (fliC mutant) had a marked decrease in the ability to adhere to T84 cells and invade both T84 and Caco-2 cells in gentamicin protection assays and by transmission electron microscopy. in addition, the aEPEC 1711-4 fliC mutant had a reduced ability to stimulate IL-8 production by Caco-2 cells in early (3-h) but not in late (24-h) infections. Our findings demonstrate that flagella of aEPEC 1711-4 are required for efficient adhesion, invasion, and early but not late IL-8 production in intestinal epithelial cells in vitro.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Colegio Doutoral Franco BrasileiroInstitut PasteurFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Programa de Apoio a Nucleos de ExcelenciaPRONEXConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, BR-04023062 São Paulo, BrazilInst Pasteur, Unite Pathogenie Bacterienne Muqueuses, F-75724 Paris 15, FranceInst Butantan, Bacteriol Lab, BR-05503900 São Paulo, BrazilInst Fleury Ensino & Pesquisa, BR-04344903 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, BR-04023062 São Paulo, BrazilInstitut Pasteur: PTR165FAPESP: 05/59128-0Web of Scienc
A new case of t(1;11)(q21;q23) in a child with M1 ANLL
Case report of a translocation : A new case of t(1;11)(q21;q23) in a child with M1 ANLL
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