It is desirable to obtain residual aberrations of designed optical systems as small as possible during the design process of optical systems. By analysis of the dependence of aberrations on the numerical aperture, it is possible to find such values of the numerical aperture, where the residual aberration is zero. These values of the numerical aperture are called correction zones. The work theoretically analyses the described problem and equations are derived for expression of wave aberration coefficients using correction zones for the third and fifth order aberrations. Moreover, it is shown the process of derivation of orthogonal polynomials that are suitable for the optical imaging theory. Using the derived polynomials, it was performed the calculation of optimal correction zones and optimal position of the centre of reference sphere for two cases: minimization of maximal deviation of the wave aberration from zero, and minimization of the root-mean-square error of wave aberration.
Physico-chemical properties and carbohydrate-binding specificity of hemagglutination activity (HA) were compared in tissue lysates and haemolymph of unfed and bloodied females of five sandfly species. Sandfly gut lectins were found to be heat-labile, sensitive to dithiotreitol treatment, freezing/thawing procedures and were affected by divalent cations. The pH optimum of HA ranged between 7.0-7.5. Specificity of gut HA of all species studied was directed towards aminosugars and some glycoconjugates, mainly lipopolysaccharide from Escherichia coli K-235, heparin and fetuin. Gut HA of Phlebotomus papatasi (Scopoli, 1786) was strongly inhibited by lipophosphoglycan (LPG) from Leishmania major promastigotes. In females, that took blood, the HA was higher but the carbohydrate-binding specificity remained the same; this suggests that the same lectin molecule was present, at different levels, both in unfed and fed flies. High HA was found in ovaries of fed females of Lutzomyia longipalpis (Lutz et Nieva, 1912), P. papatasi and P. duhoscqi Neveu-Lemaire, 1906. In P. papatasi and P. duboscqi the HA was present also in the haemolymph and head lysates of both fed and unfed females. Carbohydrate-binding specificity of HA present in these tissues was similar with the gut lectin.
The reduction in chlorophyll (Chl) and protein contents and the increase in amino acid content in leaf discs in response to aqueous SO2 exposure under continuous irradiance were more expressed in Amaranthus paniculatus (C4 plant) than in Cajanus cajan (C3 plant). The content of SH-compounds increased more in pigeonpea than in amaranth leaf discs in response to SO2. Aqueous SO2 exposure also reduced the CO2 fixation and ribulose-l,5-bisphosphate carboxylase (RuBPC) and phosphoenolpyruvate carboxylase (PEPC) activities in leaf discs of both plant species. The differences in sensitivity of these plants to SO2 were related to their conversion efficiency of SO2 to less toxic substances and sulphydryl compounds.
The paper concerns infinite paths (in particular, the maximum number of pairwise vertex-disjoint ones) in locally finite graphs and in spanning trees of such graphs.
An interference between a thermosensitive (ts) mutant and the wild-type (wt) of tick-borne encephalitis (TBE) virus in Ixodes ricinus L, and Rhipicephalus appendicuiatus (Neumann) ticks is reported. /. ricinus females were dually infected by a parenteral inoculation of ts and wt strains at 10-day interval. Interference was demonstrated by the lowered ability of wt virus to replicate in ticks previously infected by ts virus. The wt virus was demonstrated in only 30% of the ticks; the average virus titre was lowered by 2.1 log|0 compared with the control group, which was infected with the wt virus only. The oral infection of R. appendicuiatus ticks with the same viruses also revealed an interference with the growth of the superinfecting wt virus. While in the control group all the ticks became infected, in the dually infected group the wt virus was found in only 50% of the ticks. However, when the ticks were infected orally with is virus and superinfected parenterally with the wt virus, no interference was observed. In a R. appendicuiatus-derived cell line persistently infected with the ts virus (100% of the cells), a partial inhibition of the growth of the superinfecting wt virus was observed. The ts virus retained its thermosensitive phenotype throughout the persistent infection of both the ticks and the tick cell line.
The interactive effects of NO3 fertilization and salinity levels on leaf CO2 fixation, the dry matter accumulation, the proline and sugar contents in tomato shoots were determined in a greenhouse experiment using a well-controlled aerohydroponic systém. Under high salinity levels, increasing N fertilization from 5 mM NO3 up to 20 mM NO3 was ineffective in countering adverse effects of growth. Photosynthesis was inhibited as a result of both osmotic and specific ion effects. The high šalině concentrations stimulated the sugar accumulation in leaves, whereas the proline accumulation was primarily induced by increased NO3 levels.
In this article the history and current status of the standard model of electroweak interactions is briefly described. Starting with quantum electrodynamics and the phenomenological V - A theory of weak interactions, we proceed to the key theoretical concepts of the Yang-Mills field and the Higgs mechanism. The idea of the electroweak unification and the birth of the standard model is then discussed in more detail, including the peculiarities of the quark sector, anomalies and CP violation. Some open problems that could lead us to new physics beyond the standard model are mentioned in the concluding section. Future prospects of particle physics using high energy colliders are also briefly discussed., Jiří Hořejší., and Obsahuje bibliografii
The European hedgehog, Erinaceus europaeus Linnaeus, 1758, is a common host of Ixodes ricinus L. and I. hexago-nus Leach, vectors of the Lyme disease spirochaete, Borrelia burgdorferi sensu iato. To investigate whether hedgehogs are reservoirs for li- burgdorferi, hedgehogs were captured in a suburban area suitable for both tick species and in an urban area where /. ricinus is absent. The infection status of the hedgehogs was determined by xenodiagnosis using I. ricinus and I. hexagonus larvae. /. hexagonus and/or I. ricinus were found on all hedgehogs (n = 8) from the suburban area. In contrast, only I. hexagonus was infesting animals (n = 5) from the urban area. A total of 12/13 hedgehogs harboured B. burgdorferi infected ticks. Xeno-diagnostic I. ricinus and I. hexagonus larvae that fed on hedgehogs became infected. The results clearly show that European hedgehogs are reservoir hosts of the Lyme disease spirochetes. DNA of B. burgdorferi sensu stricto, В. garinii and В. afzelii was detected in culture from ear biopsy and needle aspiration material and characterized by using a genospecies-specific PCR assay. One hedgehog presented a mixed infection of the skin with fi. burgdorferi sensu stricto and fi. garinii. This study also identifies an enzootic transmission cycle in an urban area involving E europaeus and /. hexagonus. The close association of /. hexagonus with the burrows of its hosts mean that the risks of contact between /. hexagonus and humans may be low.