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Functionalisation of synthetic polymers by using enzymes has been recently demonstrated. The major advantage of enzymes over chemical processes lies in their surface specific and endo-wise mode of action. Surface hydrophilisation of PET with lipases and cutinases leads to a dramatic increase of the surfacial acid and hydroxyl group content while conventional chemical treatment does not cause any change. However, this PET-hydrolysing activity by enzymes from distinct classes has not yet been correlated to activity on natural polyesters. Here, we show that lipases, cutinases and a PHA-depolymerase are all capable of hydrolysing PET, while only lipases and cutinases also hydrolysed cutin to various degrees. Lipases showed a higher specificity for terminal fatty acids while the cutinases preferred hydroxy fatty acids during cutin hydrolysis.  相似文献   
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Algebras and Representation Theory - For a smooth irreducible affine algebraic variety we study a class of gauge modules admitting compatible actions of both the algebra $\mathcal {A}$ of functions...  相似文献   
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In this Letter we construct Abelian extensions of the group of diffecomorphisms of a torus. We consider the Jacobian map, which is a crossed homomorphism from the group of diffeomorphisms into a toroidal gauge group. A pull-back under this map of an invariant central 2-cocycle on a gauge group turns out to be an Abelian cocycle on the group of diffeomorphisms. In the case of a circle we get an interpretation of the Virasoro–Bott cocycle as a pull-back of the Heisenberg cocycle. We also give an Abelian generalization of the Virasoro–Bott cocycle to the case of a manifold with a volume form.  相似文献   
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For an affine algebraic variety X we study a category of modules that admit compatible actions of both the algebra A of functions on X and the Lie algebra of vector fields on X. In particular, for the case when X is the sphere S2, we construct a set of simple modules that are finitely generated over A. In addition, we prove that the monoidal category that these modules generate is equivalent to the category of finite-dimensional rational GL2-modules.  相似文献   
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We study the Verma modules M((μu)) over the Yangian Y associated with a simple Lie algebra . We give necessary and sufficient conditions for irreducibility of M(μ(u)). Moreover, regarding the simple quotient L((μu)) of M((μu)) as an -module, we give necessary and sufficient conditions for finite-dimensionality of the weight subspaces of L((μu)).  相似文献   
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7-Methyl-8-oxo-2'-deoxyguanosine, an analogue of the abundant promutagen 8-oxo-2'-deoxyguanosine, was incorporated into oligonucleotides and tested for its stability in various base pairs.  相似文献   
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