Theronts of the ciliate Ichthyophthirius multifiliis (Fouquet) with up to 4 micronuclei were recorded in populations from two different parasite isolates, maintained as primary infections in juvenile carp through 2 and 10 cycles, respectively. The largest number of multimicronucleate forms occurred within the older isolate (10 cycles) following cyst incubation at 20"C. Tro-phonts were induced to emerge from the host epidermis following incubation of the fish in Eagles MEM for 10-15 min at 20"C. This provided for the first time a technique to recover trophonts in all stages of development; observations were made on the transition from theront to trophont, with respect to nuclear events, the organelle of Lieberklihn, and phagocytosis of host cells. On re-exposure of carp already carrying a two-day primary infection, recently entered trophonts were found in various stages of fusion with established parasites. Results are discussed with respect to conjugation, anisogamy and senescence.
Terbium (Tb^'*") was ušed as a fluorescence probe in the study of calcium-binding sites on 33 kDa protein of photosystem 2. The fluorescence of Tb^^ was enhanced markedly when bound to the 33 kDa protein, and the non-radiative energy transfer between tryptophan (Trp) residue and Tb^+, bound to the calcium-binding sites on the 33 kDa protein, took plače. According to the Forster non-radiative energy transfer mechanism, the average distance between the bound Tb3+ and Trp residue was found to be 1.05 nm. The pH titration indicated that major groups in the 33 kDa protein, involved in Ca2+ ions binding, were the carboxylic side groups of the glutamic acid and/or aspartic acid.
Measurements of very small phase changes in optical measurement techniques are usually performed by interferometric methods that are based on evaluation of interference patterns that correspond to a phase change of the investigated wave field. If values of the phase change are small, it is difficult to determine accurately the phase values, and one needs very expensive measurement systems. Our work presents a simple method for evaluation of small phase variations that uses the interference of polychromatic light. The phase change affects the color of the interference pattern, and color of the interference pattern corresponds to a specific phase change that can be evaluated using colorimetric analysis. The colorimetric phase evaluation method is described and analysed in our work. The proposed method offers accurate results and it is suitable for practical utilization in various fields of optical testing.
In this article, the calculation of cloud point positioning with optical 3D scanner is derived. Relationships can be used for a variety of reflective configurations. They are applicable to single-mirror scanners and, for example, to polygonal scanners, even for different variations of the reflective surfaces relative to the unit coordinate axes. There is also an overview of currently available scanners including their parameters. All are suitable for terrestrial applications. and V této práci je odvozen výpočet polohy bodů mračna zaměřeného optickým 3D skenerem. Vztahy mohou sloužit pro celou řadu konfigurací rozmítací jednotky. Jsou aplikovatelné jak pro jednozrcadlové skenery, tak např. pro polygonální, a to i pro různé varianty natočení odrazných ploch vzhledem k souřadným osám jednotky. Dále je zde uveden přehled v současnosti dostupných skenerů včetně jejich parametrů. Všechny jsou vhodné pro terestrické aplikace.
An examination of a sample of European eels, Anguilla anguilla (L.), collected from Lake Bracciano near Rome in 1993, the only known European locality with the occurrence of the introduced swimbladder nematode Anguillicola novaezelandiae Moravec et Taraschewski, 1988, revealed for the first time the presence of two Anguillicola species, A. novaezelandiae and A. crassus. In view of the investigations carried out by current authors in Bracciano Lake in the years 1982-1992, it is apparent that the latter species has been introduced into the lake quite recently, where it quickly became a dominant species. The development of A. novaezelandiae was experimentally studied in the copepod intermediate host, Cyclops strenuus, for the first time. The copepods were infected with nematode second-stage larvae at 21-22°C; fully developed infective third-stage larvae were obtained 13 days p.i. The general morphology of individual larval stages of A. novaezelandiae was similar to that of larvae of the related species Λ. crassus.