In this paper, we show that K10n can be factored into C5-factors and 1-factors for all non-negative integers and satisfying 2+=10n–1.Research partially supported by an NSF-AWM Mentoring Travel Grant 相似文献
The Bryant-Ferry-Mio-Weinberger surgery exact sequence for compact homology manifolds of dimension is used to obtain transversality, splitting and bordism results for homology manifolds, generalizing previous work of Johnston.
First, we establish homology manifold transversality for submanifolds of dimension : if is a map from an -dimensional homology manifold to a space , and is a subspace with a topological -block bundle neighborhood, and , then is homology manifold -cobordant to a map which is transverse to , with an -dimensional homology submanifold.
Second, we obtain a codimension splitting obstruction in the Wall -group for a simple homotopy equivalence from an -dimensional homology manifold to an -dimensional Poincaré space with a codimension Poincaré subspace with a topological normal bundle, such that if (and for only if) splits at up to homology manifold -cobordism.
Third, we obtain the multiplicative structure of the homology manifold bordism groups .
A liquid chromatography-mass spectrometry (LC-MS)-based approach for characterizing the degree of nitration and oxidation of intact calmodulin (CaM) has been used to resolve ~250 CaM oxiforms using only 500 ng of protein. The analysis was based on high-resolution data of the intact CaM isoforms obtained by Fourier-transform ion cyclotron resonance mass spectrometry (FTICR MS) coupled with an on-line reversed-phase LC separation. Tentative identifications of post-translational modifications (PTMs), such as oxidation or nitration, have been assigned by matching observed protein mass to a database containing all theoretically predicted oxidation products of CaM and verified through a combination of tryptic peptide information (generated from bottom-up analyses) and on-line collisionally induced dissociation (CID) tandem mass spectrometry (MS/MS) at the intact protein level. The reduction in abundance and diversity of oxidatively modified CaM (i.e., nitrated tyrosines and oxidized methionines) induced by macrophage activation has been explored and semiquantified for different oxidation degrees (i.e., no oxidation, moderate, and high oxidation). This work demonstrates the power of the top-down approach to identify and quantify hundreds of combinations of PTMs for single protein target such as CaM and implicate competing repair and peptidase activities to modulate cellular metabolism in response to oxidative stress. 相似文献
The objective of this study was to evaluate the influence of size and surface functionality of amorphous silica nanoparticles
(SNPs) on their interaction with cultured cells. The intracellular uptake, phagocytic activity, and possible mechanisms of
toxicity induced by SNPs were studied on murine alveolar macrophages and two epithelial cancer cell lines. It was found that
phagocytic cells are more susceptible to amorphous SNPs than epithelial cells. SNPs with functionalized surfaces were capable
to induce the formation of apoptotic cells to a higher extent than plain particles. Plain SNPs induced plasma membrane damage
in phagocytic cells to a higher extent and caused cell death in a shorter period of time than surface-functionalized SNPs.
The prevalence of necrotic mode of cell death was observed after treatment with plain SNPs. In the range studied surface functionality
played an important role in SNPs toxicity. 相似文献
To contribute to an understanding of the nature of teachers’ mathematical knowledge and its role in teaching, the case study reported in this article investigated a teacher’s conception of a metamathematical concept, definition, and her use of examples in doing and teaching mathematics. Using an enactivist perspective on mathematical knowledge, the authors give an account of the case of Lily, a prospective, then beginning, teacher who conceived of mathematical definition as an object with particular form and function and engaged in purposeful, specialized use of examples when doing and teaching mathematics. Lily’s case illustrates how a teacher’s interpretation of examples (as exemplifications or single instances) and conception of the form and function of definitions can influence her doing and teaching mathematics. An implication is that teacher preparation should foster teachers’ abilities to use examples purposefully to provide students with rich opportunities to engage in mathematical processes such as defining. 相似文献