Solitary Subgroups

We call a subgroup A of a finite group G a solitary subgroup of G if G does not contain another isomorphic copy of A. We call a normal subgroup A of a finite group G a normal solitary subgroup of G if G does not contain another normal isomorphic copy of A. The property of being (normal) solitary can be viewed as a strengthening of the requirement that A is normal in G. We derive various results on the existence of (normal) solitary subgroups.     

The solvable radical of Sylow factorizable groups

Let G be a finite group. A complete Sylow product of G is a product of Sylow subgroups of G, one for each prime divisor of |G|. We shall call G a Sylow factorizable group if it is equal to at least one of its complete Sylow products. We prove that if G is a Sylow factorizable group then the intersection of all complete Sylow products of G is equal to the solvable radical of G. We generalize the concepts and the result to Sylow products which involve an arbitrary subset of the prime divisors of |G|. Received: 26 January 2005     

Comparison of stabilization modes of a symmetrical third-order non-linear oscillatory unit

The possibility of constructing symmetrical stabilized oscillator models that operate in several phases instead of operating in two phases, as is more usual, is considered in the present paper. In particular, symmetrical oscillator models operating in three phases are discussed comprehensively. An interesting feature of their dynamic behaviour, e.g. the appearance of limit cycles which are regionally stable and not orbitally stable, as is the case in the two phase counterpart, is suggested and dealt with.     

Functionalization of Silk Fibroin with NeutrAvidin and Biotin

New methods are needed to modify silk biomaterials with bioactive molecules for tissue engineering and drug delivery. In the present study, silk fibroin in solution or in microsphere format was coupled with NeutrAvidin via carbodiimide chemistry. Silk fibroin retained its self‐assembly features after reaction. It was found that more than four NeutrAvidin molecules bound to one silk molecule. Non‐specific binding of biotin or NeutrAvidin to silk microspheres could be reduced by pre‐treatment of the microspheres with BSA or post‐treatment with detergent. The NeutrAvidin‐coupled silk microspheres were coupled with biotinylated anti‐CD3 antibody and the functionalized microspheres were able to specifically bind to the CD3 positive T‐lymphocytic cell line Jurkat.

     

Destillation

Ohne Zusammenfassung     

Equilibrium and pre-equilibrium emissions in proton-induced reactions on <Superscript>203,205</Superscript>Tl

In this study, the excitation functions for the reactions ²⁰³Tl(p, n)²⁰³Pb, ²⁰⁵Tl(p, 3n)²⁰³Pb, ²⁰³Tl(p, 2n)²⁰²Pb, ²⁰⁵Tl(p, 4n)²⁰²Pb, ²⁰³Tl(p, 3n)²⁰¹Pb, ²⁰⁵Tl(p, 5n)²⁰¹Pb, ²⁰³Tl(p, 4n)²⁰⁰Pb and ²⁰⁵Tl(p, 6n)²⁰⁰Pb have been calculated using pre-equilibrium and equilibrium reaction mechanisms. Calculated results based on hybrid model, geometry-dependent hybrid model and cascade-exciton model have been compared with the experimental data.