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Abstract

The specific activity of natural gamma emitters like actinium (228Ac), bismuth (212Bi, 214Bi), lead (212Pb, 214Pb), potassium (40K), radium (224Ra), thallium (208Tl) and artificial radioisotope caesium (137Cs) was measured in 2005 in the surface layer of marine sediments in the northern Svalbard: Wijdefjorden, Woodfjorden, Vestfjorden and Bockfjorden as well as in the freshwater reservoirs in Andre Land. Nonuniform spatial distribution of these radionuclides was found. Sediment sample from Bockfjorden had the highest specific activities of all natural radionuclides. The specific radioactivity of 137Cs was much lower than specific radioactivities of natural radionuclides but there were differences between investigated locations. The distribution of 137Cs is similar to persistent organic pollutants of the lake sediments in the area.
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Abstract

AbstractThis papers refers to demographic processes in the period from the 19th century through to the present and tries to define what they will look like in the future. Demographic trends i.a. relating to fertility, mortality, migrations, the process of family-union-household formation and dissolution, and the process of population ageing, are described by the concepts of demographic transformations: first, second and third. The transformation of demographic trends has coexisted and will coexist with globalization processes, though the scope of the mutual influence changes over time. Despite the fact that it takes place in various geographical regions, the transformation of demographic trends is characterised by high cultural diversity and socio-economic development.
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