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41.
Let be a bounded, connected linearly convex set in with boundary. We show that the maximal ideal (both in ) and ) consisting of all functions vanishing at is generated by the coordinate functions .
Received: 2 July 2001; in final form: 26 September 2001 / Published online: 28 February 2002 相似文献
42.
Elói Medina Galego 《Monatshefte für Mathematik》2002,136(2):87-97
We study the relation of to the subspaces and quotients of Banach spaces of continuous vector-valued functions , where K is an arbitrary dispersed compact set. More precisely, we prove that every infinite dimensional closed subspace of totally incomparable to X contains a copy of complemented in . This is a natural continuation of results of Cembranos-Freniche and Lotz-Peck-Porta. We also improve our result when K is homeomorphic to an interval of ordinals. Next we show that complemented subspaces (resp., quotients) of which contain no copy of are isomorphic to complemented subspaces (resp., quotients) of some finite sum of X. As a consequence, we prove that every infinite dimensional quotient of which is quotient incomparable to X, contains a complemented copy of . Finally we present some more geometric properties of spaces.
Received 8 November 2000; in revised form 7 December 2001 相似文献
43.
Let (X,0) be the germ of a normal space of dimension n+1 and let f be the germ at 0 of a holomorphic function on X. Assume both X and f have an isolated singularity at 0. Denote by J the image of the restriction map , where F is the Milnor fibre of f at 0. We prove that the canonical Hermitian form on , given by poles of order at in the meromorphic extension of , passes to the quotient by J and is non-degenerate on . We show that any non-zero element in J produces a “mass concentration” at the singularity which is related to a simple pole concentrated at for (in a non-na?ve sense). We conclude with an application to the asymptotic expansion of oscillatory integrals , for , when .
Received: 28 May 2001 / Published online: 26 April 2002 相似文献
44.
An element σ of An, the Alternating group of degree n, is extendible in Sn, the Symmetric group of degree n, if there exists a subgroup H of Sn but not An whose intersection with An is the cyclic group generated by σ. A simple number-theoretic criterion, in terms of the cycle-decomposition, for an element of An to be extendible in Sn is given here. 相似文献
45.
Two different methods for the quantification of human tissue inhibitor of metalloproteinases-2 (TIMP-2) were developed using surface plasmon resonance (SPR) and gold nanoparticles for signal enhancement. The first method, a competitive assay, used TIMP-2 immobilized to the sensor surface and the inactive form of matrix metalloproteinase-2 (proMMP-2) (EC 3.4.24.24) adsorbed to gold nanoparticles. The sensor signals resulting from the interaction of MMP-2-gold nanoparticles with immobilized TIMP-2 were inversely proportional to the amounts of TIMP-2 of the sample. The measuring range for TIMP-2 was about 15–180 pM. The second method, a one-step sandwich assay, used proMMP-2 immobilized to the sensor surface and an anti-TIMP-2 monoclonal antibody coupled to gold nanoparticles. The lower detection limit of this assay format was 0.5 pM of TIMP-2. The binding signals were highly reproducible up to 100 pM of the inhibitor. The improvements obtained in TIMP-2 quantification over already existing tests could contribute to a better understanding and diagnosis of diseases like cancer. 相似文献
46.
In this study we describe the activation with chloroformates of Trisacryl-GF-2000, a new synthetic gel support that is stable,
hydrophilic, and contains large amounts of hydroxyl groups available for activation.
Of all the reagents tested, the activation withN-hydroxysuccinimide-chloroformate andp-nitrophenylchloroformate in organic solvents provides the best activation yield and subsequent coupling. When Trisacryl was
activated in acetone with the chloroformates in the presence of 4-dimethylaminopyridine as base and catalyst, up to 30% of
the hydroxyl groups, (i.e., 1/repeating unit) could be activated. Amino-containing ligands and proteins could be coupled to
these carriers at pH 8 or higher. For better results in affinitychromatographic applications, spacers of ε-amino caproic acid
or diaminohexane were introduced. The efficacy of these columns was demonstrated by purification of enzymes, antibodies, and
antigens. The performance of these new columns were compared with that of Sepharose columns activated in various ways. In
every case, the properties of the Trisacryl support proved superior with particular reference to the purity of the product
obtained. 相似文献
47.
Raman and IR spectra of methylarsonic acid, CH3AsO3H2, trideuteromethylarsonic acid, CD3AsO3H2 and their anions in aqueous solution and the solid state are discussed. Some results of a general valence force field and a Urey-Bradley force field are reported. 相似文献
48.
The complexity of different quality standards can, in principle, be covered by different approaches and strategies. In-depth
process mapping of quality control (QC) work streams was used by the analytical laboratories of Lonza AG to show up the principle
differences in being compliant to different quality systems. The results identified two main drivers for all necessary actions:
process-related activities and infrastructure-related activities. In addition, a clear indication of the economic impact of
these driving forces was gained, which led the laboratories to decide on a process-oriented approach. This approach has the
advantage of being able to reflect the different demands of different quality assurance (QA) regulations within the same QC
organizational structure. Following the process helps avoid unnecessary efforts in analytical work and represents a very economical
approach, at the same time, providing high flexibility to react to different QA or customer demands.
Received: 5 July 2002 Accepted: 12 November 2002
Acknowledgements The process-oriented approach resulted from many, very challenging discussions for which I would like to thank the staff
of my organization (Analytics & QC), especially, the QA staff and the LIMS team.
Presented at Analytica Conference, 23–26 April 2002, Munich, Germany
Correspondence to B. Ciommer 相似文献
49.
《Optimization》2012,61(1):77-94
In this article we study a recently introduced notion of non-smooth analysis, namely convexifactors. We study some properties of the convexifactors and introduce two new chain rules. A new notion of non-smooth pseudoconvex function is introduced and its properties are studied in terms of convexifactors. We also present some optimality conditions for vector minimization in terms of convexifactors. 相似文献
50.
《Optimization》2012,61(4):341-361
The ratio-conjugation-tool (RC) is constructed systematically, and its applicability for analysis of economic models is demonstrated. One of the main results establishes a general formula for RC of aggregative function. This tool is applied to the analysis of linear economic dynamics models of Neumann–Gale type which can be solved by a dynamic programming method: for each direct problem we construct the corresponding dual RC-problem. Moreover, we consider three examples of the most important economic dynamics models and look at these now from a unified general position. 相似文献