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排序方式: 共有516条查询结果,搜索用时 15 毫秒
1.
D. V. Artamonov 《Mathematical Notes》2007,81(5-6):573-589
A natural criterion for dimensional full-valuedness of locally compact spaces with finitely generated local homology is given. 相似文献
2.
We compute the cyclic homology of the coordinate ring A(SLq(2)) of the quantum algebraic group SL
q
(2). We observe a degeneration of the noncommutative de Rham complex. The results are also verified from the point of view of Connes' noncommutative differential geometry. 相似文献
3.
Henriques ES Floriano WB Reuter N Melo A Brown D Gomes JA Maigret B Nascimento MA Ramos MJ 《Journal of computer-aided molecular design》2001,15(4):309-322
We present the search for a new model of -factor XIIa, a blood coagulation enzyme, with an unknown experimental 3D-structure. We decided to build not one but three different models using different homologous proteins as well as different techniques and different modellers. Additional studies, including extensive molecular dynamics simulations on the solvated state, allowed us to draw several conclusions concerning homology modelling, in general, and -factor XIIa, in particular. 相似文献
4.
Cytochrome P-450 isozymes represent a critical component of nature’s spectrum of detoxification catalysts that could be exploited
for bioremediation. The ethanol-inducible human cytochrome P-450 2E1 serves as a model eukaryotic P-450 that complements the
bacterial P-450 cam in dehalogenation and detoxification of environmental pollutants. We explored the construction of novel
chimeric P-450s using cytochrome P-450 camC and 2E1 genes. For construction of chimera 1 (478 amino acids, 55.14 kDa), 145 amino acids from the N-terminus of P-450 2E1 protein
(493 amino acids, 56.84 kDa) were replaced with 130 amino acids from the N-terminus of P-450 camC protein (415 amino acids,
46.66 kDa). In chimera 2 (525 amino acids, 60.24 kDa) the strategy involves replacement of 28 amino acids in the C-terminus
of chimera 1 with 75 amino acids from the C-terminus of P-450 camC gene. Homology models of both the chimeric proteins were
developed using SWISS-MODEL based on the known crystal structure of cytochrome P-450 camC, BM-3, 1DT6A, and 2C17A. The models
indicated that the proposed heme-binding site was intact, which is inevitable for catalytic activity of cytochrome P-450s.
The expression of chimera 1 and 2 genes in Escherichia coli DH5α was evident from light-pink cell pellets, protein band in sodium dodecyl sulfate polyacrylamide gel electrophoresis,
and diagnostic carbon monoxide-difference spectra. Our studies show that strategies can be developed to exploit the natural
diversity of the P-450 superfamily to generate chimeric biocatalysts that would provide new templates amenable to directed
evolution. 相似文献
5.
《Indagationes Mathematicae》2022,33(3):546-580
We describe the homology intersection form associated to regular holonomic GKZ systems in terms of the combinatorics of regular triangulations. Combining this result with the twisted period relation, we obtain a formula of cohomology intersection numbers in terms of a Laurent series. We show that the cohomology intersection number depends rationally on the parameters. We also prove a conjecture of F. Beukers and C. Verschoor on the signature of the monodromy invariant hermitian form. 相似文献
6.
Bruce Gilligan 《Annals of Global Analysis and Geometry》1995,13(3):303-314
SupposeX=G/H is a connected homogeneous complex manifold, whereG is a Lie group andH is a closed subgroup. Assume
(X) and letG/H G/I be the holomorphic reduction ofX. If the top nonvanishing homology group ofX with coefficients in 2 is in codimension two, then either a complex Lie group acts tansitively onG/I (see [3]) orG/I is biholomorphic to the unit disk.Partially supported by NSERC Grant A3494 and by the Deutsche Forschungsgemeinschaft 相似文献
7.
Charles Weibel 《Proceedings of the American Mathematical Society》1996,124(6):1655-1662
Using hypercohomology, we can extend cyclic homology from algebras to all schemes over a ring . By `extend' we mean that the usual cyclic homology of any commutative algebra agrees with the cyclic homology of its corresponding affine scheme.
8.
LetR be a ring with unit and invariant basis property. In [1], the authors define a functorK(_;R):TOP/LIP
c-LPEP by combining the open cone construction of [7] with a geometric module construction and show this functor is a homology theory. This paper shows that if attention is restricted to objects TOP/LIP
c with a homotopy colimit structure, then the functorK(_;R) is a Quinn homology theory, In particular, for each having a homotopy colimit structure,K(;R) is a homotopy colimit in the category of -spectra. Furthermore, the constituent spectra of this homotopy colimit are obtained naturally from the fibres of .Partially supported by the National Science Foundation under grant number DMS88-03148.Partially supported by the SNF (Denmark) under grant number 11-7792. 相似文献
9.
Klaus Thomsen 《K-Theory》1991,4(3):245-267
We show that the homotopy groups of the group of quasi-unitaries inC
*-algebras form a homology theory on the category of allC
*-algebras which becomes topologicalK-theory when stabilized. We then show how this functorial setting, in particular the half-exactness of the involved functors, helps to calculate the homotopy groups of the group of unitaries in a series ofC
*-algebras. The calculations include the case of all AbelianC
*-algebras and allC
*-algebras of the formAB, whereA is one of the Cuntz algebras On n=2, 3, ..., an infinite dimensional simpleAF-algebra, the stable multiplier or corona algebra of a-unitalC
*-algebra, a properly infinite von Neumann algebra, or one of the projectionless simpleC
*-algebras constructed by Blackadar. 相似文献
10.
We show that the only rational homology spheres which can admit almost complex structures occur in dimensions two and six. Moreover, we provide infinitely many examples of six-dimensional rational homology spheres which admit almost complex structures, and infinitely many which do not. We then show that if a closed almost complex manifold has sum of Betti numbers three, then its dimension must be a power of two. 相似文献