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1.
P. Symonds 《Commentarii Mathematici Helvetici》1998,73(3):400-405
We show that the quotient space of the p-subgroup complex of a finite group by the action of the group is contractible. This was conjectured by Webb.
Received: June 28, 1996 相似文献
2.
The author of this paper has shown previously how a complexrepresentation of a finite group can be split into a virtualsum of representations induced from one-dimensional representationsof subgroups in a natural way (sometimes known as explicit Brauerinduction). Here the modular case is treated, yielding an analogousresult at the level of Brauer characters in general, and inthe Green ring for trivial source modules. 2000 MathematicsSubject Classification 20C20 (primary); 55M35, 14F20 (secondary). 相似文献
3.
Symonds Ria; Lawson Duncan; Robinson Carol 《Teaching Mathematics and its Applications》2008,27(3):140-149
This article reports the findings of qualitative research undertakento seek to identify the key reasons why some students are notengaging with mathematics support provided by Loughborough University.The research involved a number of focus groups and onthe spot interviews with non-users fromacross the campus. Barriers identified include a lack of awarenessof the location of support and a fear of embarrassment. Furtherinterviews were conducted with regular users of the supportin an attempt to understand how some of these barriers to usagemight be overcome. The article will discuss actions that maybe taken to improve student engagement with mathematics supportand the issue of how student motivation may affect such action. 相似文献
4.
We prove a relative version of the theorem of Webb that the augmented chain complex of the p-subgroup complex of a finite group, considered as a complex of modules for the group, is homotopy equivalent to a complex of projectives. This allows us to take into account the group of automorphisms of the group. 相似文献
5.
Clementine Cailleteau Ludovic Micallef Clemence Lepage Philippe Jean-Paul Cardot Jean-Louis Beneytout Bertrand Liagre Serge Battu 《Analytical and bioanalytical chemistry》2010,398(3):1273-1283
Differentiation therapy could be one strategy for stopping cancer cell proliferation. A plant steroid, diosgenin, is known
to induce megakaryocytic differentiation in human erythroleukemia (HEL) cells. In recent studies, the use of sedimentation
field-flow fractionation (SdFFF) allowed the preparation of subpopulations that may differ in regard to sensitivity to differentiation
induction. The specific goal of this study was to determine the relationship between cell cycle stage and sensitivity to megakaryocytic
differentiation induction of HEL cells. After first confirming the capacity of diosgenin to specifically select targets, hyperlayer
SdFFF cell sorting was used to prepare fractions according to cell cycle position from crude HEL cells. The sensitivities
of these fractions to diosgenin-induced differentiation were then tested. The coupling of SdFFF cell separation to imaging
flow cytometry showed that G1-phase cells were more sensitive to differentiation induction than S/G2M-phase cells, confirming
the relationship between cell status at the start of induction, the extent of the biological event, and the potential of SdFFF
in cancer research. 相似文献
6.
Weiss BM Symonds H Spong P Ladich F 《The Journal of the Acoustical Society of America》2007,122(6):3710-3716
Vocal communication within and between groups of individuals has been described extensively in birds and terrestrial mammals, however, little is known about how cetaceans utilize their sounds in their natural environment. Resident killer whales, Orcinus orca, live in highly stable matrilines and exhibit group-specific vocal dialects. Single call types cannot exclusively be associated with particular behaviors and calls are thought to function in group identification and intragroup communication. In the present study call usage of three closely related matrilines of the Northern resident community was compared in various intra- and intergroup contexts. In two out of the three matrilines significant changes in vocal behavior depending both on the presence and identity of accompanying whales were found. Most evidently, family-specific call subtypes, as well as aberrant and variable calls, were emitted at higher rates, whereas "low arousal" call types were used less in the presence of matrilines from different pods, subclans, or clans. Ways in which the observed changes may function both in intra- and intergroup communication. 相似文献
7.
Stephan Pritz Yvonne Wolf Clementine Klemm Michael Bienert 《Tetrahedron letters》2006,47(33):5893-5896
The phosphonium-type coupling reagent PyBOP, when applied to the synthesis of peptide nucleic acid (PNA) oligomers, was found to form O4-phosphonium compounds of the nucleobase guanine which can be converted into C4-modified guanine-derived PNAs by nucleophiles. 相似文献
9.
In the introduction to [3] it is mistakenly claimed that Mislin'sproof uses Carlsson's proof of Segal's Burnside ring conjecture.In fact, Mislin uses instead the work of Carlsson, Miller andLannes on Sullivan's fixed-point conjecture, and work of Dwyerand Zabrodski [1]. There is, however, a proof by Snaith [2]that depends on a version of the Segal conjecture. 2000 MathematicsSubject Classification 20J06 (primary), 20C05 (secondary). 相似文献
10.
J. J. Cruywagen I. F. J. Van der Merwe Luigi R. Nassimbeni Margaret L. Niven Elizabeth A. Symonds 《Journal of chemical crystallography》1986,16(4):525-535
On standing, an acid solution of tungstate yields single crystals of the paratungstate salt Na10[H2W12O42]·26H2O. The space group is P¯1, (No. 2),a=11.811(2),b=12.486(2),c=12.206(2) Å,=82.29(1),=115.12(1), =113.76(1)°,V=1485.6 Å3,Z=1. The structure was solved by direct methods and refined toR=0.0397,R
w
=0.0403 [w=(
2
F)–1]. The 12 WO6 octahedra (shared edges and vertices) are distorted from regular geometry; one of the sodium ions exhibits disorder and there is extensive hydrogen bonding between the water molecules and the oxygens of the paratungstate anion. 相似文献