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51.
In this paper, we propose a new general method to compute rigorously global smooth branches of equilibria of higher-dimensional
partial differential equations. The theoretical framework is based on a combination of the theory introduced in Global smooth solution curves using rigorous branch following (van den Berg et al., Math. Comput. 79(271):1565–1584, 2010) and in Analytic estimates and rigorous continuation for equilibria of higher-dimensional PDEs (Gameiro and Lessard, J. Diff. Equ. 249(9):2237–2268, 2010). Using this method, one can obtain proofs of existence of global smooth solution curves of equilibria for large (continuous)
parameter ranges and about local uniqueness of the solutions on the curve. As an application, we compute several smooth branches
of equilibria for the three-dimensional Cahn–Hilliard equation. 相似文献
52.
53.
Hardelauf H Sisnaiske J Taghipour-Anvari AA Jacob P Drabiniok E Marggraf U Frimat JP Hengstler JG Neyer A van Thriel C West J 《Lab on a chip》2011,11(16):2763-2771
Spatially defined neuronal networks have great potential to be used in a wide spectrum of neurobiology assays. We present an original technique for the precise and reproducible formation of neuronal networks. A PDMS membrane comprising through-holes aligned with interconnecting microchannels was used during oxygen plasma etching to dry mask a protein rejecting poly(ethylene glycol) (PEG) adlayer. Patterns were faithfully replicated to produce an oxidized interconnected array pattern which supported protein adsorption. Differentiated human SH-SY5Y neuron-like cells adhered to the array nodes with the micron-scale interconnecting tracks guiding neurite outgrowth to produce neuronal connections and establish a network. A 2.0 μm track width was optimal for high-level network formation and node compliance. These spatially standardized neuronal networks were used to analyse the dynamics of acrylamide-induced neurite degeneration and the protective effects of co-treatment with calpeptin or brain derived neurotrophic factor (BDNF). 相似文献
54.
The structure and absolute configuration of natural 8-epi-9-deoxygoniopypyrone have been confirmed by an efficient and highly diastereoselective synthesis in 15 steps from (S)-mandelic acid with an overall yield of 43%. 相似文献
55.
SUMMARY: Sarcoidosis is a multisystem disease with various clinical manifestations. It is characterized primarily on a histopathologic basis by the presence of noncaseating granulomata. Laryngeal involvement reportedly occurs in 3-5% of cases, and it is typically localized to the supraglottic region. Patients often present with hoarseness, dysphagia, stridor, or dyspnea. Laryngoscopy typically demonstrates a pale, edematous epiglottis studded with nodules. Tissue biopsy reveals the classic noncaseating granuloma; however, the finding is not diagnostic. Sarcoidosis remains a diagnosis of exclusion to be entertained once other verifiable etiologies for granulomatous disease of the larynx, such as TB, syphilis, fungal infection, berylliosis, or Wegener's granulomatosis, have been ruled out. Systemic corticosteroids remain the mainstay of treatment; however, new steroid-sparing therapies that target the inflammatory response of sarcoidosis are currently being investigated. The case history of a patient with laryngeal sarcoidosis who was managed with the immunosuppressant azathioprine (Imuran) is summarized along with a discussion of other treatment options. 相似文献
56.
Nathalie Deruelle Jean-Philippe Uzan 《International Journal of Theoretical Physics》1997,36(11):2461-2468
We briefly recall the problem of defining conserved quantities such as energy in general relativity, and the solution given
by introducing a symmetric background. We apply the general formalism to perturbed Robertson-Walker spacetimes with de Sitter
geometry as background. We relate the obtained conserved quantities to Traschen's integral constraints and mention a few applications
in cosmology. 相似文献
57.
Paul Godin 《Journal of Differential Equations》2002,183(1):224-238
We give a complete discussion of the C∞ or analytic regularity of blow-up curves for Cauchy problems or some mixed problems for the Liouville equation in one space dimension. In the case of mixed problems, the regularity results depend on the boundary condition: actually, we show the existence of a sequence of boundary conditions for which the regularity of the blow-up curve is better than in the general case. 相似文献
58.
Henk Schierbeek Denise Rook Frans W. J. te Braake Kristien Y. Dorst Gardi Voortman Jean‐Philippe Godin Laurent‐Bernard Fay Johannes B. van Goudoever 《Rapid communications in mass spectrometry : RCM》2009,23(18):2897-2902
Determination of glutathione kinetics using stable isotopes requires accurate measurement of the tracers and tracees. Previously, the precursor and synthesized product were measured with two separate techniques, liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) and gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). In order to reduce sample volume and minimize analytical effort we developed a method to simultaneously determine 13C‐glutathione as its dimeric form (GSSG) and its precursor [1‐13C]glycine in a small volume of erythrocytes in one single analysis. After having transformed 13C‐glutathione into its dimeric form GSSG, we determined both the intra‐erythrocytic concentrations and the 13C‐isotopic enrichment of GSSG and glycine in 150 µL of whole blood using liquid chromatography coupled to LC/IRMS. The results show that the concentration (range of µmol/mL) was reliably measured using cycloleucine as internal standard, i.e. with a precision better than 0.1 µmol/mL. The 13C‐isotopic enrichment of GSSG and glycine measured in the same run gave reliable values with excellent precision (standard deviation (sd) <0.3‰) and accuracy (measured between 0 and 5 APE). This novel method opens up a variety of kinetic studies with relatively low dose administration of tracers, reducing the total cost of the study design. In addition, only a minimal sample volume is required, enabling studies even in very small subjects, such as preterm infants. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
59.
Jean-Philippe Rocher Mohammed Ahmar Joelle Paris 《Journal of heterocyclic chemistry》1988,25(2):599-601
Condensation of dimethyl 3-methylglutaconate with ketones provides a one pot route for the preparation of 5-methoxycarbonyl-4-methyldihydropyran-2-ones. The experimental conditions to give selectively pyran-2-ones isomers are discussed. The structure of the different products was established on the basis of 1H and 13C nmr spectral data. 相似文献
60.
We show that pointlike defect model of glasses cannot explain the thermodynamic properties of glass formers, as for example, the excess specific heat close to the glass transition, contrary to the claim of Garrahan and Chandler [Proc. Natl. Acad. Sci. U.S.A. 100, 9710 (2003)]. More general models and approaches in terms of extended defects are also discussed. 相似文献