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41.
MnBi films were prepared by annealing Bi-Mn composite films. The grain size of the MnBi films was strongly influenced by the
temperatureT
s
of the film substrate during evaporation of Bi and Mn. For 55-nm-thick films, the numberN of MnBi grains per mm2 decreased from 4×106 per mm2 forT
s
=+90°C to 1 per mm2 forT
s
=−40°C. The diameters of the largest grains observed were about 5 mm. For interpretation of this result, the formation process
of MnBi films was observed magneto-optically and electronmicroscopically. It was found thatN was determined by the structure of Bi in the Bi-Mn composite films and that this strongly depended onT
s
. 相似文献
42.
43.
Edward Harms 《Nuclear Physics A》1975,247(1):51-58
The improved method of moments procedure which was developed in an earlier paper is applied to the solution of the three-body scattering equations for separable two-body interactions. Results of these calculations further support conclusions reached previously that the improved method of moments provides a rapid and accurate calculational procedure for solving scattering problems. 相似文献
44.
45.
G. Alexander L. Criegee H.C. Dehne K. Derikum R. Devenish G. Flügge G. Franke Ch. Gerke E. Hackmack P. Harms G. Horlitz Th. Kahl G. Knies E. Lehmann R. Schmitz R.L. Thompson U. Timm K. Wacker 《Physics letters. [Part B]》1978,76(5):652-656
The polarization of the f0(1270) and ?0(770) produced in the J/ψ decays into f0γ and ?0π0 are measured in e+e? collisions at 3.1 GeV. A fit to the f0 production and decay angular distributions yields the values A1/A0 = 0.6 ± 0.3 and A2/A0 = 0.3 ?1.6+0.6, where Aλ are the f0 helicity amplitudes. These results are in good agreement with the values predicted from a QCD two-gluon-exchange model. In addition an upper limit of 2.3 × 10?4 is obtained for the J/ψ → f′0(1514) γ decay branching ratio which implies Γ(J/ψ → f′γ)/Γ(J/ψ → f0γ) ? 0.12 ± 0.05. 相似文献
46.
47.
Eira Jansson-Verkasalo Timo Ruusuvirta Minna Huotilainen Paavo Alku Elena Kushnerenko Kalervo Suominen Seppo Rytky Mirja Luotonen Tuula Kaukola Uolevi Tolonen Mikko Hallman 《BMC neuroscience》2010,11(1):1-7
Background
Protein aggregation plays important roles in several neurodegenerative disorders. For instance, insoluble aggregates of phosphorylated tau and of Aβ peptides are cornerstones in the pathology of Alzheimer's disease. Soluble protein aggregates are therefore potential diagnostic and prognostic biomarkers for their cognate disorders. Detection of the aggregated species requires sensitive tools that efficiently discriminate them from monomers of the same proteins. Here we have established a proximity ligation assay (PLA) for specific and sensitive detection of Aβ protofibrils via simultaneous recognition of three identical determinants present in the aggregates. PLA is a versatile technology in which the requirement for multiple target recognitions is combined with the ability to translate signals from detected target molecules to amplifiable DNA strands, providing very high specificity and sensitivity.Results
For specific detection of Aβ protofibrils we have used a monoclonal antibody, mAb158, selective for Aβ protofibrils in a modified PLA, where the same monoclonal antibody was used for the three classes of affinity reagents required in the assay. These reagents were used for detection of soluble Aβ aggregates in solid-phase reactions, allowing detection of just 0.1 pg/ml Aβ protofibrils, and with a dynamic range greater than six orders of magnitude. Compared to a sandwich ELISA setup of the same antibody the PLA increases the sensitivity of the Aβ protofibril detection by up to 25-fold. The assay was used to measure soluble Aβ aggregates in brain homogenates from mice transgenic for a human allele predisposing to Aβ aggregation.Conclusions
The proximity ligation assay is a versatile analytical technology for proteins, which can provide highly sensitive and specific detection of Aβ aggregates - and by implication other protein aggregates of relevance in Alzheimer's disease and other neurodegenerative disorders. 相似文献48.
Colorless single crystals of Cd2[μ8‐MTB] · 3H2O · DMF ( 1 ) were prepared in DMF/H2O solution [ 1 : space group C2/c (no. 15) with a = 1821.30(6), b = 2175.08(6), c = 1269.87(4) pm, β = 129.684(1)°]. The connection between the methane‐p‐benzoate tetraanions (MTB4–) and the Cd2+ cations leads to a three‐dimensional framework with channels extending along [1 10] and [110] with openings of 670 pm × 360 pm. The channel‐like voids accommodate water molecules and N,N‐dimethylformamide (DMF) molecules not bound to Cd2+. Colorless single crystals of [Cd4(2,2′‐bipy)4(μ7‐MTB)2] · 7DMF ( 2 ) were prepared in DMF in the presence of 2,2′‐bipyridine [ 2 : space group P1 (no. 2) with a = 1224.84(4), b = 1418.85(5), c = 2033.49(4) pm, α = 85.831(2)°, β = 88.351(2)°, γ = 68.261(1)°]. The coordination of MTB4– to Cd2+ results in infinite layers parallel to (001). The layers, not connected by any hydrogen bonds, contain small openings of about 320 pm × 340 pm. 相似文献
49.
Philipp S. Steinlandt Wei Zuo Dr. Klaus Harms Prof. Dr. Eric Meggers 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(67):15333-15340
A new class of bis-cyclometalated rhodium(III) catalysts containing two inert cyclometalated 6-tert-butyl-2-phenyl-2H-indazole ligands and two labile acetonitriles is introduced. Single enantiomers (>99 % ee) were obtained through a chiral-auxiliary-mediated approach using a monofluorinated salicyloxazoline. The new chiral-at-metal complex is capable of catalyzing the visible-light-induced enantioselective α-cyanoalkylation of 2-acyl imidazoles in which it serves a dual function as the chiral Lewis acid catalyst for the asymmetric radical chemistry and at the same time as the photoredox catalyst for the visible-light-induced redox chemistry (up to 80 % yield, 4:1 d.r., and 95 % ee, 12 examples). 相似文献
50.