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  • Author or Editor: M Kovács x
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This work deals with the leaf blade anatomical structures of the broad-leaved fescue taxa, natural populations of temperate forage grasses, collected from various habitats in Central Europe. The following anatomical features were examined and quantitatively characterised: the ribs of leaves, type of the mesophyll, number of the sclerenchyma ribs, quantity of sclerenchyma tissue, presence of the colourless cells, number of bulliform cells, stomatal complexes and presence of papilla number. It was concluded that the anatomical structures and the main leaf blade characteristics of broad-leaved fescues show several differences between the taxa of Schenodorus and Drymanthele subgenus. The populations of the Schenodorus subgenus present heterogeneous mesophyll, with radial parenchyma, and colourless cells. Strong correlations exist between the bulliform cells and the quantity of sclerenchyma and papillae. The populations of Drymanthele subgenus also present heterogeneous mesophyll, but this is not evident for every taxa and populations. The radial parenchyma and the colourless cells are not specific. There is a positive correlation between the bulliform cells and the quantity of sclerenchyma. The comparative leaf anatomical analysis, could contribute to the better understanding of taxonomic and anatomical diversity in this group.

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The phase changes in the solid state in E AlMgSi alloy are discussed. The dissolution and precipitation processes are investigated by DTA, and the results can be applied to control the technological parameters of dissolution heat treatments.

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Histological and electron microscopic examinations of the kidneys of 8 dogs suffering from fatal, naturally acquired Babesia canis infection and nephropathy are presented. Seven animals were treated with imidocarb dipropionate on average 4.5 days prior to death. Severe anaemia was present only in 2 cases. Degenerative histological changes observed mostly in the proximal convoluted tubules included vacuolar-hydropic degeneration, necrosis and detachment of renal tubular epithelial (RTE) cells from the basement membrane. Necrotic debris occasionally formed acidophilic casts within the tubules. In some cases, necrosis of the whole tubule was observed. Haemoglobin casts in the tubules and haemoglobin droplets in RTE cells seldom appeared. No significant histological changes were seen in the glomeruli. Ultrastructural lesions in RTE cells included nuclear membrane hyperchromatosis, karyopyknosis, karyolysis, swelling or collapse of mitochondria with fragmentation of cristae and vacuolar-hydropic degeneration in the endoplasmic reticulum and microvilli. Nuclear oedema was also observed. Many RTE cells exhibiting necrosis collapsed. Vacuolar-hydropic degeneration and necrosis were also observed in the glomerular and interstitial capillary endothelium. The severe acute tubular necrosis described in this study is probably the result of hypoxic renal injury. Systemic hypotension leading to vasoconstriction in the kidneys might be the most important cause of renal hypoxia in B. canis infections, but anaemia may also contribute to inadequate oxygenation. Imidocarb should be applied with caution in patients with possible renal involvement until further data become available on its potential nephrotoxicity in dogs.

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The aim of dogrose breeding for fruit purposes is to select genotypes suitable for cultivation and to produce new genotypes by crossing. Physical and chemical analyses, prospective genotypes have been developed from R. inodora , R. corymbifera, R. rubiginosa and R. canina varieties.In the course of the investigations, the highest vitamin C content was found in the hips of R. inodora and R. rubiginosa . The glucose and fructose contents ranged from 9.57–13.36 g/100 g, averaged over several years. The amounts of these two carbohydrates were equal, or in some taxa (e.g. R. corymbifera, R. canina Sz3) the fructose content was higher.The glucose, fructose and vitamin C contents changed at different rates in each taxon during ripening. The results showed that the fructose content reached its peak a week earlier than the glucose content. The vitamin C content of morphological varieties of R. canina did not change substantially during ripening.

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A widely described phenomenon all over Europe is that reed decline begins from greater water depths - i.e. clumping is more expressed at the open water fringe while stands towards the lakeshore are homogeneous and intact. To understand the possible background processes, the present paper examined the differences between the element concentrations of reed organs (root, rhizome, stem and leaf), and the substrate (i.e. sediment or soil) along water depth gradients in Lake Balaton, Hungary. Differences between the mineral compositions of reed organs and the substrate and the impact of water depth on element concentration of samples were investigated. Relations between water depth and element concentrations of substrate and plant organs and interelement correlations in the samples were also considered. In addition to other results, element concentrations provided indirect evidence for increasing hypoxia (anoxia) in the sediment under greater water depths possibly contributing to reed decline. Although, the greater water depth is associated with higher element concentrations in the substrate, the uptake of minerals in reed are impeded by anoxia. Towards the greater water depth, for instance, the higher N concentration of substrate was not associated with more N in leaves (even a slight decrease was observed). On the other hand, elements (e.g. Fe and S) with increasing availability in reduced state, reached high concentrations in reed leaves from greater water depth, which may also indicate the insufficient O2 level in the rhizosphere

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Authors: J. Boldvai, M. Götz and E. Posgay-Kovács
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Authors: Muammel M. Hanon, Márk Kovács and László Zsidai

3D printing of Acrylonitrile Butadiene Styrene (ABS) and Poly Lactic Acid (PLA) were used to prepare specimens utilising fused deposition modelling (FDM) technology. Two colours of PLA filament were printed; white and grey, whereas ABS only in white colour. Determining the tribological properties of 3D printed samples have been carried out, through obtaining the frictional features of different 3D printable filaments. Alternating-motion system employed for measuring the tribological factors. Studying the difference between static and dynamic friction factors and the examination of wear values were included. A comparison among the tribological behaviour of the 3D printed polymers has been investigated. The printed white ABS and PLA specimens show insignificant differences in the results tendency. On the contrary, the grey PLA exhibits a considerable variation due to the incredible growth in the coefficient of friction and wear average as well.

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In recent years 56 accessions of Triticum timopheevii Zhuk. (2n=4x=28, AtAtGG) were characterized for the main phenotypic and resistance characters. Among these accessions 38 originated from the base species together with subspecies and varietas forms thereof, and 18 belong to the subspecies armeniacum group. After the evaluation of field assessment data gathered over 12 years, the most promising 11 accessions were selected for a crossability trial with cultivated einkorn. As a result of this trial, the accession with the highest seed set (Acc. No.: MVGB845) was chosen for the development of a new synthetic amphiploid using the same semi-dwarf line of diploid cultivated einkorn (Triticum monococcum L. ssp. monococcum 1T-1, 2n=2x=14, AmAm) as in the crossability trial. This einkorn line was bred in Martonvásár, and has both outstanding resistance and other promising phenotypic and agronomic characters.After crossing the accession MVGB845 with 1T-1, the triploid hybrids were treated with colchicine to obtain fertile progenies with a doubled genome. The newly developed synthetic hexaploid wheat breeding stock (named Triticum timococcum Kost., 2n=6x=42, AtAtGGAmAm) could ease the introgression of valuable resistance genes into bread wheat at the hexaploid level (bridge-crossing).The aim of the present research was to redevelop Triticum timococcum based on a detailed characterization of gene bank accessions, and to introduce this new material into wheat breeding.

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Authors: Míra Mándoki, M. Dobos-Kovács, T. Bakonyi and M. Rusvai

Kidney samples from chickens diagnosed with acute nephritis and gout were subjected to histological and electron microscopic examination. The investigations revealed cytoplasmic inclusion bodies in the tubular epithelial cells containing round virions of about 30 nm in diameter. Since avian nephritis virus (ANV) is known as a potential causative agent of the so-called baby chick nephropathy, an RT-PCR assay was developed for the molecular detection of ANV-specific nucleic acid in the specimen. The specificity of the assay was confirmed by direct sequencing of the amplicon obtained in the reaction. The nucleotide sequence of the PCR product showed 92% identity with the reference ANV sequence deposited in the GenBank database. After having been validated on some other suspicious cases of avian nephritis, the PCR method described in this study can be a potential tool for routine diagnostic examination of samples submitted from cases of gout and nephropathy in chickens.

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