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991.
At present, compared with bovine milk, the characterization of donkey milk caseins is at a relatively early stage progress, and only limited data are related to its genetic polymorphism. In this work, the heterogeneity of donkey caseome was investigated using a proteomic approach, based on one- (PAGE, UTLIEF) and two-dimensional (PAGE → UTLIEF) electrophoresis, stained with either Coomassie Brilliant Blue or specific polyclonal antibodies, and structural MS analysis. These combined methodologies allowed the contemporary identification of donkey αs1, αs2, β and κ-CN with their related heterogeneity due to phosphorylation (αs1, αs2 and β-CN), glycosylation (κ-CN) and incorrect splicing of RNA in mRNA (deleted forms of αs1-CN and β-CN). The results achieved showed 11 components for κ-CN, six phosphorylated components for β and αs1-CN and three main phosphorylated components for αs2-CN, each accounting for 10, 11 and 12 P/mole. At this regard, for the first time, the primary structure of the expressed protein corresponding to the only available donkey αs2-CN cDNA sequence was determined. Furthermore β-CN was found in homozygous and heterozygous state for the occurrence of a genetic β-CN variant having a MW value 28 mass units higher than the common β-CN phenotype.  相似文献   
992.
Fe-Pt thin films were deposited by rf sputtering on an MgO substrate heated at different temperatures to induce the formation of the perpendicular Fe-Pt L10 phase with a different grain morphology on the nanometer scale. All films are characterized by a mazelike pattern of FePt nanograins with interconnected bases. MFM images and magnetization curves indicate that all samples have a strong perpendicular magnetic anisotropy arising from (0 0 1) growth. The temperature behaviour of the electrical resistance indicates that a percolating path exists for conduction electrons in the mazelike pattern. The magnetoresistance was measured as a function of magnetic field (applied longitudinally) and temperature in the ranges −70 kOe<H<+70 kOe and 4 K<T<150 K, respectively. All samples display a complex behaviour of the electrical resistance as a function of applied field. The role of the different magnetoresistance effects (both intrinsic and extrinsic) measured in these FePt thin films is elucidated.  相似文献   
993.
Poly-BF3a, a new hydrophobic polymer obtained by spontaneous polymerization of 1-methylene-3-phenyl-1H-indene, was found to give nanoparticles characterized by favorable shape and dimensions. Poly-BF3a nanoparticles were loaded with CR3124, a potent 5HT3 antagonist, as a drug model by desolvation methods either in the absence or in the presence of polyethylene glycol (PEG1000) as a wetting agent. The SEM studies showed that the introduction of CR3124 into the preparation led to a variable degree of aggregation–cementation, which afforded a sort of nanocomposite material. In the absence of PEG1000, the drug molecule was found to stay in the amorphous state (DSC studies) when its percentage is not higher than 10% by weight. In vitro release experiments showed that the formation and stability of the dispersion as well as the drug release were remarkably affected by the presence of PEG1000, demonstrating its beneficial effect to the nanoparticle morphology and disaggregation.  相似文献   
994.
We present a morphologic and spectroscopic study of cluster-assembled TiO x films deposited by supersonic cluster beam source on clean silicon substrates. Data show the formation of nanometer—thick and uniform titanium silicides film at room temperature (RT). Formation of such thick TiSi x film goes beyond the classical interfacial limit set by the Ti/Si diffusion barrier. The enhancement of Si diffusion through the TiO x film is explained as a direct consequence of the porous film structure. Upon ultra high vacuum annealing beyond 600 °C, TiSi2 is formed and the oxygen present in the film is completely desorbed. The morphology of the nanostructured silicides is very stable for thermal treatments in the RT—1000 °C range, with a slight cluster size increase, resulting in a film roughness an order of magnitude smaller than other TiO x /Si and Ti/Si films in the same temperature range. The present results might have a broad impact in the development of new and simple TiSi synthesis methods that favour their integration into nanodevices.  相似文献   
995.
The inclusive Higgs production cross section from gluon fusion is calculated through NNLO QCD, including its top quark mass dependence. This is achieved through a matching of the 1/M t expansion of the partonic cross sections to the exact large- $\hat{s}$ limits which are derived from k T -factorization. The accuracy of this procedure is estimated to be better than 1% for the hadronic cross section. The final result is shown to be within 1% of the commonly used effective theory approach, thus confirming earlier findings.  相似文献   
996.
We report on the numerical analysis of the area correlations in spin foam gravity on a single 4-simplex considered by Rovelli [C. Rovelli, Phys. Rev. Lett. 97 (2006) 151301]. We compare the asymptotics and confirm the inverse squared distance leading behaviour at large scales. This supports the recent advances on testing the semiclassical limit of the theory. Furthermore, we show that the microscopic discreteness of the theory dynamically suppresses and regularizes the correlations at the Planck scale.  相似文献   
997.
An interacting scalar field with largish coupling to curvature can support a distinctive inflationary universe scenario. Previously this has been discussed for the Standard Model Higgs field, treated classically or in a leading log approximation. Here we investigate the quantum theory using renormalization group methods. In this model the running of both the effective Planck mass and the couplings is important. The cosmological predictions are consistent with existing WMAP5 data, with 0.967?ns?0.980.967?ns?0.98 (for Ne=60Ne=60) and negligible gravity waves. We find a relationship between the spectral index and the Higgs mass that is sharply varying for mh∼120–135 GeVmh120135 GeV (depending on the top mass); in the future, that relationship could be tested against data from PLANCK and LHC. We also comment briefly on how similar dynamics might arise in more general settings, and discuss our assumptions from the effective field theory point of view.  相似文献   
998.
O. Adriani  G. A. Bazilevskaya  G. C. Barbarino  T. R. Bellotti  M. A. Bzheumikhova  E. A. Bogomolov  V. M. Boezio  V. Bonvicini  M. Bongi  L. Bonechi  S. Bottai  A. Bruno  A. Vacchi  E. Vannuccini  G. V. Vasiliev  S. A. Voronov  A. M. Galper  L. A. Grishantseva  G. Zampa  N. Zampa  V. G. Zverev  M. Casolino  T. D. Campana  P. Carlson  G. Castellini  F. Cafagna  A. N. Kvashnin  S. V. Koldashov  S. Yu. Krutkov  A. A. Leonov  V. V. Malakhov  V. Malvezzi  L. Marcelli  W. Menn  V. V. Mikhailov  E. Mocchiutti  S. Orsi  G. Osteria  P. Papini  M. P. De Pascale  T. P. Picozza  M. Pearce  G. De Rosa  M. Ricci  S. B. Ricciarini  M. Simon  N. De Simone  R. Sparvoli  P. Spillantini  Yu. I. Stozhkov  E. Taddei  V. Di Felice  D. Fedele  P. Hofverberg  Yu. T. Yurkin 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(3):364-366
Secondary electron and positron fluxes in the energy range from 3 MeV to 7 GeV were measured with the ARINA and PAMELA spectrometers onboard the Resurs-DK satellite launched on June 15, 2006 into an elliptical orbit with an inclination of 70.4° and an altitude of 350–600 km. It is shown that positrons dominate over electrons by a factor of up to 4–5 in the geomagnetic equator region (L < 1.2 and B > 0.25).  相似文献   
999.
O. Adriani  G. A. Bazilevskaya  G. C. Barbarino  R. Bellotti  M. Boezio  E. A. Bogomolov  L. Bonechi  M. Bongi  V. Bonvicini  S. V. Borisov  S. Bottai  A. Bruno  F. Cafagna  D. Campana  P. Carlson  M. Casolino  G. Castellini  M. P. De Pascale  G. De Rosa  D. Fedele  V. Di Felice  A. M. Galper  L. A. Grishantseva  P. Hofverberg  A. A. Leonov  S. V. Koldashov  S. Yu. Krutkov  A. N. Kvashnin  V. Malvezzi  L. Marcelli  W. Menn  V. V. Mikhailov  M. Minori  E. Mocchiutti  S. Orsi  G. Osteria  P. Papini  M. Pearce  P. Picozza  M. Ricci  S. B. Ricciarini  M. Simon  N. De Simone  R. Sparvoli  P. Spillantini  Yu. I. Stozhkov  E. Taddei  A. Vacchi  E. Vannuccini  G. V. Vasil’ev  S. A. Voronov  Yu. T. Yurkin  G. Zampa  N. Zampa  V. G. Zverev 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(5):568-570
The PAMELA experiment is being carried out on board the Russian satellite Resurs DK1 placed in the near-earth near-polar orbit on June 15, 2006. The apparatus comprising a silicon-strip magnetic spectrometer and an electromagnetic calorimeter allows measurement of electron and positron fluxes in cosmic rays in a wide energy interval from ~100 MeV to hundreds of GeV. The high-energy electron and positron separation technique is discussed and the data on positron-to-electron ratio in primary cosmic rays up to E ≈ 10 GeV from the 2006–2007 measurements are reported in this work.  相似文献   
1000.
F. Ambrosino  A. Antonelli  M. Antonelli  F. Archilli  P. Beltrame  G. Bencivenni  C. Bini  C. Bloise  S. Bocchetta  F. Bossi  P. Branchini  G. Capon  D. Capriotti  T. Capussela  F. Ceradini  P. Ciambrone  E. De Lucia  A. De Santis  P. De Simone  G. De Zorzi  A. Denig  A. Di Domenico  C. Di Donato  B. Di Micco  M. Dreucci  G. Felici  S. Fiore  P. Franzini  C. Gatti  P. Gauzzi  S. Giovannella  E. Graziani  M. Jacewicz  V. Kulikov  G. Lanfranchi  J. Lee-Franzini  M. Martini  P. Massarotti  S. Meola  S. Miscetti  M. Moulson  S. Müller  F. Murtas  M. Napolitano  F. Nguyen  M. Palutan  A. Passeri  V. Patera  P. Santangelo  B. Sciascia  A. Sibidanov  T. Spadaro  L. Tortora  P. Valente  G. Venanzoni  R. Versaci 《The European Physical Journal C - Particles and Fields》2009,64(4):627-636
We present a precise measurement of the ratio R K =Γ(Ke ν(γ))/Γ(Kμ ν(γ)) and a study of the radiative process Ke ν γ, performed with the KLOE detector. The results are based on data collected at the Frascati e + e ? collider DAΦNE for an integrated luminosity of 2.2 fb?1. We find R K =(2.493±0.025stat±0.019syst)×10?5, in agreement with the Standard Model expectation. This result is used to improve constraints on parameters of the Minimal Supersymmetric Standard Model with lepton flavor violation. We also measured the differential decay rate dΓ(Ke ν γ)/dE γ for photon energies 10<E γ < 250 MeV. Results are compared with predictions from theory.  相似文献   
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