Marcel Weiden

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The genome of the protozoan Trypanosoma brucei contains a set of about 100 minichromosomes of about 50 to 150 kb in size. The small size of these chromosomes, their involvement in antigenic variation, and their mitotic stability make them ideal candidates for a structural analysis of protozoan chromosomes and their telomeres. We show that a subset of the(More)
In this article we look at the relatively new notion of " business rules ". We propose a new classification scheme for business rules, which is aimed at providing more support for business-rule elicitation. We show how this scheme was applied in a domain of offering mortgages. As a result we formulate guidelines for eliciting business rules and for choosing(More)
Using Raman scattering we studied the effect of substitutions on 1D spin fluctuations in CuGeO 3 observed as a spinon continuum in frustration induced exchange scattering. For temperatures below the spin-Peierls transition (T SP =14K) the intensity of this continuum at 120-500 cm −1 is exponentially suppressed and transferred into a 3D two-magnon density of(More)
In a magnetic substance the gap in the Raman spectrum, ∆ R , and the neutron scattering gap, ∆ S , are related by ∆ R /∆ S ≈ 2 if the the magnetic excitations (magnons) are only weakly interacting. But for CuGeO 3 the experimentally observed ratio is of the order ∆ R /∆ S ∼ 1.49 − 1.78, indicating attractive magnon-magnon interactions in the quasi-1D(More)
Protozoa represent a diverse group of single-celled eukaryotes, many of which have parasitic life styles, infecting hundreds of millions of people. Unique aspects of their biology relate to their distinct evolutionary position and their complex life cycles, frequently involving different hosts.
  • M H Weiden
  • 1971
The discovery of effective insecticidal materials among the carbamic-acid esters is surveyed to provide insight into some of the factors leading to the development of new control agents. Problems associated with attempts to correlate insecticidal activity with acetylcholinesterase inhibition are outlined. The intoxication syndrome is described and its(More)
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