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861.
862.
863.
Günter F. Steinke 《Results in Mathematics》1993,24(3-4):326-341
It is shown that a 2-dimensional Laguerre plane that admits a closed connected 4-dimensional point-transitive group of automorphisms must be classical. Further, up to conjugacy in the automorphism group of the classical real Laguerre plane, all closed connected 4-dimensional point-transitive subgroups are determined. 相似文献
864.
Geometric continuity is a central topic of Computer Aided Geometric Design. In this paper we study the geometric continuity of arbitrary order between tensor product Bézier surfaces of arbitrary degree.
Herrn Prof. Dr. Oswald Giering zum 60. Geburtstag gewidmet 相似文献
Herrn Prof. Dr. Oswald Giering zum 60. Geburtstag gewidmet 相似文献
865.
Sebastien Couillard-Despres Eike Quehl Katrin Altendorfer Claudia Karl Sonja Ploetz Ulrich Bogdahn Juergen Winkler Ludwig Aigner 《BMC neuroscience》2008,9(1):31
Background
During developmental and adult neurogenesis, doublecortin is an early neuronal marker expressed when neural stem cells assume a neuronal cell fate. To understand mechanisms involved in early processes of neuronal fate decision, we investigated cell lines for their capacity to induce expression of doublecortin upon neuronal differentiation and develop in vitro reporter models using doublecortin promoter sequences. 相似文献866.
Lukas Biesen Nithiya Nirmalananthan‐Budau Katrin Hoffmann Ute Resch‐Genger Thomas J. J. Müller 《Angewandte Chemie (International ed. in English)》2020,59(25):10037-10041
N‐Benzyl aroyl‐S,N‐ketene acetals can be readily synthesized by condensation of aroyl chlorides and N‐benzyl 2‐methyl benzothiazolium salts in good to excellent yields, yielding a library of 35 chromophores with bright solid‐state emission and aggregation‐induced emission characteristics. Varying the substituent from electron‐donating to electron‐withdrawing enables the tuning of the solid‐state emission color from deep blue to red. 相似文献
867.
Silver- and Coomassie-staining protocols: detection limits and compatibility with ESI MS 总被引:3,自引:0,他引:3
Staining protocols for PAGE have to be sensitive and should not impair further MS analysis of selected samples. In this study, the MS compatibility of different silver- and Coomassie-staining protocols with a nano-LC-MS/MS system was systematically elucidated. Altogether, 13 different silver-staining, 1 imidazole-staining and 2 Coomassie-staining protocols were used and compared to each other for their achieved sequence coverage and their detection sensitivity. Three proteins were used as model proteins (bovine serum albumin, rabbit L-lactate dehydrogenase, bovine milk beta-lactoglobulin) in decreasing concentration (12 pmol down to 30 fmol) and different staining protocols were applied. The conclusion of this study is that two silver-staining protocols (Blum, H. et al.,. Electrophoresis 1987, 8, 93-99 and Shevchenko, A. et al.,. Anal. Chem. 1996, 68, 850-858) combine good sequence coverage and good sensitivity and are recommended for nano-LC-MS/MS analysis. 相似文献
868.
We consider the motion of a fluid in the exterior of a rotating obstacle. This leads to a modified version of the Stokes system which we consider in the whole space ${\mathds R}^n$, n = 2 or n = 3 and in an exterior domain $D\subset {\mathds R}^3$. For every q ∈ (1, ∞) we prove existence of solutions and estimates in function spaces with weights taken from a subclass of the Muckenhoupt class Aq. Moreover, uniqueness is shown modulo a vector space of dimension 3. © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim 相似文献
869.
Christina L. Crawford Stephan Graf Marc Gonin Katrin Fuhrer Xing Zhang Herbert H. HillJr. 《International Journal for Ion Mobility Spectrometry》2011,14(1):23-30
Increasing the dimensionality of an analysis enables more detailed and comprehensive investigations of complex mixtures. One
dimensional separation techniques like gas chromatography (GC) and ion mobility spectrometry (IMS) provide limited chemical
information about complex mixtures. The combination of GC, ion mobility spectrometry, and time-of-flight mass spectrometry
(GC-IM-TOFMS) provides three-dimensional separation of complex mixtures. In this work, a hybrid GC-IM-TOFMS with a secondary
electrospray ionization (SESI) source provided four types of analytical information: GC retention time, ion mobility drift
time, mass-to-charge ratios, and ion intensity. The use of secondary electrospray ionization enables efficient and soft ionization
of gaseous sample vapors at atmospheric pressure. Several complex mixtures, including lavender and peppermint essential oils,
were analyzed by GC-SESI-IM-TOFMS. The resulting 3D data from these mixtures, each containing greater than 50 components,
were plotted as 3D projections. In particular, post-processed data plotted in three dimensions showed that many mass selected
GC peaks were resolved into different ion mobility peaks. This technique shows clear promise for further in-depth analyses
of complex chemical and biological mixtures. 相似文献
870.
Loerting T Winkel K Seidl M Bauer M Mitterdorfer C Handle PH Salzmann CG Mayer E Finney JL Bowron DT 《Physical chemistry chemical physics : PCCP》2011,13(19):8783-8794
Many acronyms are used in the literature for describing different kinds of amorphous ice, mainly because many different preparation routes and many different sample histories need to be distinguished. We here introduce these amorphous ices and discuss the question of how many of these forms are of relevance in the context of polyamorphism. We employ the criterion of reversible transitions between amorphous "states" in finite intervals of pressure and temperature to discriminate between independent metastable amorphous "states" and between "substates" of the same amorphous "state". We argue that the experimental evidence suggests we should consider there to be three polyamorphic "states" of ice, namely low-(LDA), high-(HDA) and very high-density amorphous ice (VHDA). In addition to the realization of reversible transitions between them, they differ in terms of their properties, e.g., compressibility, or number of "interstitial" water molecules. Thus they cannot be regarded as structurally relaxed variants of each other and so we suggest considering them as three distinct megabasins in an energy landscape visualization. 相似文献