399,299 research outputs found
Production matrices for geometric graphs
We present production matrices for non-crossing geometric graphs on point sets in convex position, which allow us to derive formulas for the numbers of such graphs. Several known identities for Catalan numbers, Ballot numbers, and Fibonacci numbers arise in a natural way, and also new formulas are obtained, such as a formula for the number of non-crossing geometric graphs with root vertex of given degree. The characteristic polynomials of some of these production matrices are also presented. The proofs make use of generating trees and Riordan arrays.Postprint (updated version
Two-photon mediated resonance production in e+e- collisions: cross sections and density matrices
Earlier described model amplitudes are used in this paper to evaluate both
cross sections and density matrices for two-photon mediated resonance
production in e^+e^- collisions. All 25 q\bar{q} low-lying ^1S_0, ^3P_J and
^1D_2 resonances can thus be treated. Two independent methods are described to
obtain the resonance production density matrices and cross sections. These
density matrices combined with a resonance decay density matrix give the
detailed angular distributions of the resonance decay products. For two
particular decays, \chi_{c2},\chi_{c1}\to\gamma J/\psi the details are given.
Several numerical results are presented as well.Comment: 27 pages, 4 figure
Production of lectin-affinity matrices for process-scale glycoprotein purification
A selection of prokaryotic lectins with a variety of glycan specificities and affinities have been identified, cloned, expressed in Eschericia coli and characterised. The aims of this project are to:
- express the lectins at 1L scale to produce sufficient quantities for immobilisation studies (~100 mg)
- immobilisethelectinsonSepharose
- evaluate lectin performance on column by monitoring their ability toreproducibly capture and elute glycoprotein glycoforms
- …