Nereis diversicolor O.F. Müller and N. succinea Frey et Leuckart (Polychaeta, Nereidae) living in brackish shallow areas in Denmark are naturally infected with tetractinomyxon actinospores. Infected Nereis spp. were experimentally fed to various potential fish hosts, and the actinosporean stages developed into myxosporean stages of Ellipsomyxa gobii Køie, 2003 (Ceratomyxidae) in the gallbladder of the common goby Pomatoschistus microps (Krøyer) (Gobiidae). The European eel Anguilla anguilla (L.), three-spined stickleback Gasterosteus aculeatus L., small sand eel Ammodytes tobianus L., flounder Platichthys flesus (L.), European plaice Pleuronectes platessa L. and common sole Solea solea (L.) did not become experimentally infected. In Danish shallow brackish areas P. microps is naturally infected with E. gobii, in some areas with a prevalence >90%. We compared small subunit ribosomal DNA sequences of the actinosporean with E. gobii from P. microps. Sequences were identical, which further verifies that both forms belong to the same organism. This is the first myxozoan two-host life cycle in the marine environment.
Authors examine issue of abortion in the Czech Republic in the era of socialism and in post-communism period. They compare statistical data (collected by Czech Statistical Office) and data from public opinion survey concerning abortions and reproduction trends. Data from public opinion survey differs from the statistical one and it cannot prove that a special group of women prefer abortion as a solution of the unwanted pregnancy. The paper handles the topics such as models of reproduction behavior in socialism based on statistical data. Authors present that the abortion was used as a specific way of contraception before the 1989, particularly by the married women with two and more children and childless women get the abortion occasionally. The abortion rate started to slump after the decline of state socialism especially due to the spread of modern contraception. However, during the 1990s the number of childless women who got abortion increased.
The basic quantum equations for transverse electron wave modes in an electrically conducting metallic or semiconductor homogeneous mesoscopic thin layer are formulated and interpreted in dependence on the adequate static tranverse parabolic extend of the interior electric potential energy and operated external tuning homogeneous magnetostatic field. The starting point is the modified non-temporal schrödinger equation of one electron with chosen normalized monowave number wavefunction and relevant transverse eigenfunctions and eigenenergies. Their analysis is then directed successively towards the transverse electric, magnetic and magneto-electric electron wave modes. The established separated transverse wave modes in electron waveguides under discussion are analogous to the transverse wave modes of electromagnetic waveguides. The problems mentioned above are topical and important in practice for development of integrated electronical, opto-electronical and electro-optical systems. and V článku jsou formulovány a interpretovány základní kvantové vzorce pro příčné elektronové vlnové módy v elektricky vodivé kovové nebo polovodičové homogenní mezoskopické tenké vrstvě v závislosti na přiměřeném statickém příčném parabolickém rozložení vnitřní elektrické potenciální energie a působícím vnějším ladicím homogenním magnetostatickém poli. Východiskem je modifikovaná nečasová Schrödingerova rovnice jednoho elektronu se zvolenou normovanou monovlnočtovou vlnovou funkcí a příslušnými vlastními příčnými vlnovými funkcemi a vlastními energiemi. Jejich analýza je pak postupně zaměřena k příčným elektrickým, magnetickým a magneto - elektrickým elektronovým vlnovým módům. Zavedené separované příčné vlnové módy v diskutovaných elektronových vlnovodech jsou analogické s příčnými vlnovými módy v elektromagnetických vlnovodech. Jde o aktuální problematiku s praktickým významem pro rozvoj integrovaných elektronických, optoelektronických a elektrooptických systémů.