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131.
J. E. Scott 《Structural chemistry》2007,18(3):257-265
Our shape is defined and maintained by the connective tissues (skin, tendons, cartilages, blood vessels, etc.) or more precisely
by their extracellular matrices. These highly ordered supramolecular organisations are modules of protein fibrils held together
by elastic carbohydrate strings. I called these the ‘shape modules.’ The ‘laws.’ which underpin this tissue jigsaw, the changes
which come with age and the insight that the concepts give in economically important disorders such as osteoarthrosis begin
to provide a new and coherent picture stretching across the animal world and its evolution. This structure/function picture
is built on biochemical analyses, which developed into histochemical microscopy and thence into electron histochemistry, and
from nuclear magnetic resonance (NMR), molecular modelling and computer simulations on the physicochemical and biomechanical
side. As usual, originality bred dissent. 相似文献
132.
We prove an existence result for topologically locally flat embeddings of 2-spheres in simply connected 4-manifolds. This topological result is deduced from a splitting theorem for pointed Hermitian modules over a cyclic group ring. A stability result for such modules is also proved. This applies to the isotopy classification of locally flat embeddings.Partially supported by the NSF. 相似文献
133.
左R—模E是ann—内射的。如果对于R的每个有限生成右零化子理想r(L)到R的R—模同态都能延拓为到E的R—模同态.同样,我们称左R—模M是ann—平坦的如果对于R的每个有限生成右零化子理想r (L),都可以得到正合列0→r(L)⊕_RM→R__R⊕M.在本文中,我们证明了R—模B是ann—平坦的当且仅当它的示性模B~·=Hom_R(B,Q/Z)是ann—内射的. 相似文献
134.
Summary We characterize finitely generated Laskerian modules over a commutative ring in terms of weakly associated prime ideals. 相似文献
135.
F. E. A. Johnson 《K-Theory》2005,34(2):141-150
In [F.E.A. Johnson, Stable Modules and the D(2)-Problem, LMS Lecture Notes In Mathematics, vol. 301, CUP (2003)], for finite groups G, we gave a parametrization of the stable class of the augmentation ideal of Z[G] in terms of stably free modules. Whilst the details of this parametrization break down immediately for infinite groups,
nevertheless one may hope to find parallel arguments for restricted classes of infinite groups. Subject to the restriction
that Ext1(Z, Z[G]) = 0, we parametrize the minimal level in Ω1(Z) by means of stably free modules and give a lower estimate for the size of Ω1(Z). 相似文献
136.
137.
ON Δ-GOOD MODULE CATEGORIES OF QUASI-HEREDITARY ALGEBRAS 总被引:2,自引:0,他引:2
A useful reduction is presented to determine the finiteness of △-good module category F(△)of a quasi-heredltary algebra. As an application of the reduction, the f(△)-finitenetess of quasi-hereditary M-twisted double incidence algebras of posets is discussed. In particular, a complete classification of F(△)-finite M-twisted double incidence algebras is given in case the posets are linearly ordered. 相似文献
138.
Xiang Fang 《Journal of Functional Analysis》2003,198(2):445-464
We define and study Hilbert polynomials for certain holomorphic Hilbert spaces. We obtain several estimates for these polynomials and their coefficients. Our estimates inspire us to investigate the connection between the leading coefficients of Hilbert polynomials for invariant subspaces of the symmetric Fock space and Arveson's curvature invariant for coinvariant subspaces. We are able to obtain some formulas relating the curvature invariant with other invariants. In particular, we prove that Arveson's version of the Gauss-Bonnet-Chern formula is true when the invariant subspaces are generated by any polynomials. 相似文献
139.
SUP-阿基米德T模合成算子模糊关系方程的求解 总被引:1,自引:0,他引:1
论文根据阿基米德 T模的一些特性 ,给出求解 SUP-阿基米德 T模合成算子模糊关系方程的方法 ,以及求解最大解和全体极小的解方法 . 相似文献
140.
广义幂级数环的Morita对偶 总被引:1,自引:0,他引:1
设A,B是有单位元的环, (S,≤)是有限生成的Artin的严格全序幺半群, AMB是双模.本文证明了双模[[AS,≤]][MS,≤][[BS,≤]]定义一个Morita对偶当且仅当 AMB定义一个Morita对偶且A是左noether的,B是右noether的.因此A上的广 义幂级数环[[AS,≤]]具有Morita对偶当且仅当A是左noether的且具有由双模AMB 诱导的Morita对偶,使得B是右noether的. 相似文献