534 research outputs found
Embedding surfaces into with maximum symmetry
We restrict our discussion to the orientable category. For , let
be the maximum order of a finite group acting on the closed surface
of genus which extends over , where the maximum
is taken over all possible embeddings . We will
determine for each , indeed the action realizing .
In particular, with 23 exceptions, is if or
if , and moreover can be realized by unknotted
embeddings for all except for and .Comment: 42 pages, 37 figures, 6 tables of figure
Graphs in the 3--sphere with maximum symmetry
We consider the orientation-preserving actions of finite groups on pairs
, where is a connected graph of genus , embedded
in . For each we give the maximum order of such acting on
for all such . Indeed we will classify all
graphs which realize these in different levels: as
abstract graphs and as spatial graphs, as well as their group actions.
Such maximum orders without the condition "orientation-preserving" are also
addressed.Comment: 34 pages, to appear in Discrete Comput. Geo
Bordered surfaces in the 3-sphere with maximum symmetry
We consider finite group actions on the 3-sphere which leave invariant an embedded, compact, bounded surface of algebraic genus g > 1 (orientable or non-orientable), and determine for each g the maximum order of such an action. For example, the maximal possibility 12(g-1) is obtained for the finitely many values g = 2, 3, 4, 5, 9, 11, 25, 97, 121 and 241. For each g > 1, we classify the topological types of the surfaces and their embeddings into the 3-sphere
Characterization and Quantification of Livestock Odorants using Sorbent Tube Sampling and Thermal Desorption coupled with Multidimensional Gas Chromatography–Mass Spectrometry–Olfactometry
Characterization and quantification of livestock odorants is one of the most challenging analytical tasks because odor-causing gases are very reactive, polar and often present at very low concentrations in a complex matrix of less important or irrelevant gases. The objectives of this research is to develop a novel analytical method for characterization of the livestock odorants including their odor character, odor intensity, and hedonic tone and further quantitative analysis of the key odorants responsible for livestock odor emissions. Sorbent tubes packed with Tenax TA were employed for sampling. The automated one-step thermal desorption coupled with multidimensional gas chromatography-mass spectrometry-olfactometry system was developed for simultaneous chemical and odor analysis. Fifteen odorants identified from different livestock species operations are quantified. In addition, odor character, odor intensity and hedonic tone associated with each of the target compounds are also analyzed. The method developed in this research is being used on a multistate, multispecies project focused on quantifying odor and chemical analysis of odor
Embedding compact surfaces into the 3-dimensional Euclidean space with maximum symmetry
We give the maximum orders of finite group actions on Euclidean 3-space which leave invariant an embedded compact bordered surface (orientable or non-orientable), in terms of the algebraic genus of the surface. We also identify the topological types of the bordered surfaces realizing the maximum order, and find simple representative embeddings for such surfaces
- …