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21.
Hermann P Hermelink A Lausch V Holland G Möller L Bannert N Naumann D 《The Analyst》2011,136(6):1148-1152
Tip-enhanced Raman spectroscopy (TERS) is a highly sensitive spectroscopic technique which combines the advantages of optical spectroscopy with the requirements needed for the characterization of biological nano-structures. In this study, TERS was used to investigate the applicability of this spectroscopic technique for the detection of different virus strains like avipoxvirus and adeno-associated virus. TERS spectra obtained from different particles of the same virus strain show variations in relative peak intensities and positions of most spectral features observed. These spectral variations were higher for the larger avipoxvirus particles (?≈350 nm) than for the smaller adeno-associated virus particles (?≈26 nm). 相似文献
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23.
Gudrun Freitag 《Journal of multivariate analysis》2005,94(1):123-158
Semiparametric models to describe the functional relationship between k groups of observations are broadly applied in statistical analysis, ranging from nonparametric ANOVA to proportional hazard (ph) rate models in survival analysis. In this paper we deal with the empirical assessment of the validity of such a model, which will be denoted as a “structural relationship model”. To this end Hadamard differentiability of a suitable goodness-of-fit measure in the k-sample case is proved. This yields asymptotic limit laws which are applied to construct tests for various semiparametric models, including the Cox ph model. Two types of asymptotics are obtained, first when the hypothesis of the semiparametric model under investigation holds true, and second for the case when a fixed alternative is present. The latter result can be used to validate the presence of a semiparametric model instead of simply checking the null hypothesis “the model holds true”. Finally, various bootstrap approximations are numerically investigated and a data example is analyzed. 相似文献
24.
Lutz Grotjahn Ronald Frank Gudrun Heisterberg-Moutsis Helmut Blöcker 《Tetrahedron letters》1984,25(47):5373-5376
Negative ion FAB-MS is recommended for the rapid routine identification of monomeric as well as oligomeric building blocks used in the phosphotriester synthesis of DNA fragments. 相似文献
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Acyl- and Alkylidenephosphines. XXV. Molecular and Crystal Structure of 1,2-Di(tert-butyl)-3-dimethylamino-1-thio-4-trimethylsilylsulfano-1λ5, 2λ3-diphosphet-3-ene The title compound 1 formed in a nearly quantitative yield by decomposition of tert-butyl(N,N-dimethylthiocarbamoyl)trimethylsilylphosphine, crystallizes in the orthorhombic space group P212121 with {a = 1067.3(1); b = 1077.1(1); c = 1924.6(5) pm; Z = 4} at +20°C. An X-ray structure determination (RG = 0.038) shows two tert-butyl groups at a four- (P1) and a three-coordinate phosphorus atom (P2) to be placed on different sides of the four membered ring. Characteristic bond lengths as well as the angles at the atoms P1, P2, C3, and C4 inside the ring have already been given above. 相似文献
27.
Gudrun Schappacher 《Applications of Mathematics》2005,50(4):355-386
The notion of the Orlicz space is generalized to spaces of Banach-space valued functions. A well-known generalization is based on N-functions of a real variable. We consider a more general setting based on spaces generated by convex functions defined on a Banach space. We investigate structural properties of these spaces, such as the role of the delta-growth conditions, separability, the closure of
, and representations of the dual space. 相似文献
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29.
Arianna Passerini M. Cristina Patria Gudrun Thäter 《Annali di Matematica Pura ed Applicata》1997,173(1):43-62
In this paper we consider a domain which is tube-like at one exit to infinity and the halfspace at the other side. We prove existence of steady motions for the Navier-Stokes problem and for the case in which the fluid is moving through a porous medium at rest filling . In both cases the proof holds for arbitrary fluxes. We describe the asymptotic behaviour of the solutions in the halfspace for both problems. 相似文献
30.
Markt P McGoohan C Walker B Kirchmair J Feldmann C De Martino G Spitzer G Distinto S Schuster D Wolber G Laggner C Langer T 《Journal of chemical information and modeling》2008,48(8):1693-1705
The cysteine protease cathepsin S (CatS) is involved in the pathogenesis of autoimmune disorders, atherosclerosis, and obesity. Therefore, it represents a promising pharmacological target for drug development. We generated ligand-based and structure-based pharmacophore models for noncovalent and covalent CatS inhibitors to perform virtual high-throughput screening of chemical databases in order to discover novel scaffolds for CatS inhibitors. An in vitro evaluation of the resulting 15 structures revealed seven CatS inhibitors with kinetic constants in the low micromolar range. These compounds can be subjected to further chemical modifications to obtain drugs for the treatment of autoimmune disorders and atherosclerosis. 相似文献