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The colouration of the underparts of the Barn Owl ranges in Europe from reddish-brown to white. This character, that shows a clinal variation, is thought to be a marker of subspecies identity. The subspecific identity or transitional state of a total 64 Barn Owl Tyto alba pairs was determined on the basis of their phenotypic characteristics. The present authors investigated the breadth of the transition zone in Hungary on the basis of the distribution of the white-chested subspecies and the transitional phenotype, and it was found to be at least 500 km wide. The width of the transition zone may result from the lack of preferences in mating pair choice. The observed pattern of phenotypic distribution is due to the marginal location of the studied population in the transition zone.
Temperature dependences of components of the complex modul us of rigidity and complex electric permittivity of freeze-dried starch gel were obtained for the temperature interval from about 100 to 500 K. At low-temperature region relaxation process with free energy of activation of about 38 kJ /mol related with release of reorientational degrees of freedom of the polar hydroxymethylol groups was observed in DETA as well as in DMTA tests. Secondary relaxation processes with activation energies of 48 and 67 kJ /mol found in mechanical spectra only were ascribed to the local conformational mobilities of polymeric chains.
We have recently developed a transformation method for representation of different relaxation processes data (DMTA, DETA and 1H-NMR) as a function of free energy of activation in freeze-dried wheat starch gel. In our previous paper [12] the method of transformation was applied for freeze-dried wheat starch gel of density of 0.13 g/cm3, while in this paper we present results of a similar analysis of relaxation parameters measured in a wide temperature range in dehydrated wheat starch gel of a twice lower density. In the system studied, we observed a decreasing value of the complex rigidity modulus, due to much lower degree of crosslinking. Similar courses of dispersion profile obtained with 1H-NMR relaxation method and DMTA method, at temperature ranging from 100 to 380 K, point to a correlation between the nuclear and mechanical relaxation processes, confirming the results of our previous work, which are related to the dynamics of hydroxymethylene groups in freeze-dried starch gel.
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