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Cryptosporidial and microsporidial infection on the pig farms, in the Czech Republic
HANZLÍKOVÁ, Dagmar
The cryptosporidia and microsporidia are worldwide spread opportunistic parasites. With regard to their wide host spectra and zoonotic potential there is a significant risk for immunocompromised humans, especially AIDS patients. Natural Cryptosporidium infections in pigs are widespread but generally apathogenic. A total of 411 faecal samples, 39 of sows, 127 of pre-weaned, 122 of post-weaned piglets and 123 of pre-growers from three farms were screened for Cryptosporidium spp. infection using the aniline-carbol-methyl violet staining method and positive molecular characterized (direct sequencing of partial SSU rRNA partial genes and PCR-RFLP at the SSU rRNA). Overall, infections were detected in 84 out of 411 animals (20 %), with highest infection rates among post-weaners (27 %). All positive samples were genotyped based on SSU rRNA sequence analysis. C. suis, Cryptosporidium pig genotype II, and C. muris were detected. The microsporidial infections are very frequent in breeds of pigs. Pigs have been frequently reported to be infected with E. bieneusi. Spores were detected in 258 samples of 342 (75 %). The high prevalence was determined in pre-growers (86 %). Genotyping based on the ITS regions of the rRNA gene identified that most pigs were infected with the species-specific genotype F, while two animals had the zoonotic genotype D and two had genotype Peru 9.
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Fiscal rules in selected EU countries between 2004-2015: sensible method for consolidation of public finances or fad of politicians?
Veselý, Lukáš ; Strejček, Ivo (advisor) ; Chmelová, Pavla (referee)
The subject of fiscal rules is very topical issue. The rise of public debt in certain developed countries resulted in what is sometimes called "debt crisis". Debt of those countries which is higher than their annual gross domestic product is viewed as unpayable by some economists. The main objective of this thesis has been to prove or disprove hypothesis that the fiscal rules studied in this paper are an effective solution for public finance consolidation. This verification was based on the analysis of fiscal rules functioning in selected countries between 2004 and 2015. As per results of analysis the paper aims to give recommendations for the Czech financial constitution proposal. The actual results of inquiry proved the hypothesis. Well-chosen fiscal rules are the right way towards fiscal consolidation, provided they are observed. Fiscal rules making thus requires an emphasis to be placed on the well-formulated exit clauses altogether with prospective sanctions. The current Czech financial constitution proposal is built on the correctly picked fiscal rule type, although the reference value lacks economic sense and it would not lead, with a high degree of probability, towards fiscal consolidation.
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Pulsed liquid jet generated by pulse multiplication technique
Dvorský, R. ; Sitek, Libor ; Sochor, T.
First theoretical papers summarizing the high mechanical energy cumulation when high-speed drops impacting the solid surface as a result of the water hammer effect have been known since 1960’s. Heymann has demonstrated that pressure maximum in the impact of a spherical drop of a liquid is several times higher than the presupposed maximum for the classical water hammer effect. The latter maximum pressure itself exceeds the mere stagnation pressure of the continuous jet many times hereat. When developing devices for pulse jet generation a new generalization of the classical water hammer theory for high pressures has been implemented. Based on this the new patented principle of “pulse multiplication” has been formulated. The pulse multiplier is the source of high-pressure pulses with 100% depth of modulation of liquid jet discharge velocity that allows increasing the jet disintegration effect significantly without the abrasive material application.
Fulltext: content.csg -  DOC
Plný tet: UGN_0398574 - DOC
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Microstructural Investigation and Mechanical Testing of an Ultrafine-grained Austenitic Stainless Steel
Chlupová, Alice ; Man, Jiří ; Polák, Jaroslav ; Karjalainen, L. P.
Special thermomechanical treatment based on high degree deformation followed by reversion annealing was applied to 301LN austenitic stainless steel to achieve ultrafine-grained (UFG) structure with considerably enhanced mechanical properties. Two different conditions of the thermomechanical treatment were adopted and resulting microstructures with different grain sizes were characterised by optical and high resolution scanning electron microscopy (SEM-FEG). Hardness measurements and tensile tests were performed to characterize mechanical properties. To reveal structural changes induced during thermomechanical treatment and during tensile tests a magnetic induction method was additionally applied. Experimental study validated the ability of the above special treatment to produce austenitic stainless steel with grain size about 1.4 m which exhibits tensile strength about 1000MPa while ductility remains on level about 60 %. The results obtained for both thermomechanical conditions are compared and the relationship between microstructure refinement, phase content and mechanical properties is discussed.
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Molecular characterization of selected strains of amoebae of the genus Acanthamoeba, the potential human parasites.
ŠTAUBEROVÁ, Kamila
The genus Acanthamoeba belongs to a group of organisms generally called "amoebae". These amoebae can cause fatal disease in humans, being able to enter e.g. through skin in bloodstream and then spreading through the body. In the body they further parasitize in various tissues including the brain there they cause a little known disease called "granulomatous amoebic encephalitis". The disease is most prevalent in people previously ill with, e.g., systemic lupus erythematosus. Granulomatous amoebic encephalitis leads especially to a brain inflammation, which evolves in brain tissue necrosis. Most prominent symptoms are headaches, nausea and vomiting, aphasia and ataxia. This work mentions also some other amoebae as Neagleria fowleri, Balamuthia mandrillaris, Sappinia diploidea a Entamoeba histolytica. Neagleria fowleri is known as a causative agent of an illness called primary amoebic encephalitis. First, I had isolated DNA using Genomic Mini Kit from five amoeba strains. The next step was PCR amplification it is a method depending on alternation of high and lower temperatures in thermocycler. It was followed by electrophoresis, where the presence of bands in agarose gel, which I had prepared myself, showed the presence of absence of amoebic DNA fragments. In case of successful amplification (presence of PCR product) the fragment was excised from gel with scalpel and transferred in a test-tube. The DNA was then cleaned via extraction. The extraction was done with Gel/DNA Fragments Extraction Kit. An intermediate step before sequencing, we tried to clone the product it became obvious that this way is not very effective. The sequencing was provided by the company Seqme. Following work with sequences was conducted in programs BioEdit and alignment in ClustalX. Then, phylogenetic trees were computed in the program PAUP and viewed in TreeView. The results were interpreted in the terms of relationships between the amoebae majority of them belonged to the most common genotype, T4, but their relations within the genotype were not so tight. Concerning the clinical samples available to me (both from human eyes), one of them (O1) belonged to T4 genotype, whereas the other one (O2) belonged to the genotype T3. Another result was evaluation of the effectivity of different primers: specific primers AcaJDP1 and AcaJDP2 were much more efficient than originally used "eukaryotic" primers ERIB1 and ERIB10.
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Changes in structure and phase composition in the surface of tram rail
Švábenská, Eva ; Roupcová, Pavla ; Schneeweiss, Oldřich
We have investigated structure and phase composition of surface layer of tram rails after long time running and the results were compared with those obtained on the original part of material. Changes due to effects of severe plastic deformation together with thermal shocks by friction process were expected. The information about structure and phase composition was obtained by optical and scanning electron microscopy, X-Ray Powder Diffraction, Mössbauer Spectroscopy and Glow Discharge Emission Spectroscopy (GDOES) and this was completed by microhardness measurements. The results show that the surface layer in comparison with the original material exhibits important changes in grain structure, an increase in microhardness and high content of iron oxide and hydrooxides. According to the depth profile of the chemical composition measured by GDOES there is an increase in carbon content in the surface layer which can be effect of up-hill diffusion.
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STRAIN ENGINEERING OF THE ELECTRONIC STRUCTURE OF 2D MATERIALS
del Corro, Elena ; Peňa-Alvarez, M. ; Morales-García, A. ; Bouša, Milan ; Řáhová, Jaroslava ; Kavan, Ladislav ; Kalbáč, Martin ; Frank, Otakar
The research on graphene has attracted much attention since its first successful preparation in 2004. It possesses many unique properties, such as an extreme stiffness and strength, high electron mobility, ballistic transport even at room temperature, superior thermal conductivity and many others. The affection for graphene was followed swiftly by a keen interest in other two dimensional materials like transition metal dichalcogenides. As has been predicted and in part proven experimentally, the electronic properties of these materials can be modified by various means. The most common ones include covalent or non-covalent chemistry, electrochemical, gate or atomic doping, or quantum confinement. None of these methods has proven universal enough in terms of the devices' characteristics or scalability. However, another approach is known mechanical strain/stress, but experiments in that direction are scarce, in spite of their high promises.\nThe primary challenge consists in the understanding of the mechanical properties of 2D materials and in the ability to quantify the lattice deformation. Several techniques can be then used to apply strain to the specimens and thus to induce changes in their electronic structure. We will review their basic concepts and some of the examples so far documented experimentally and/or theoretically.
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