Development and mapping of DArT markers within the Festuca - Lolium complex

<p>Abstract</p> <p>Background</p> <p>Grasses are among the most important and widely cultivated plants on Earth. They provide high quality fodder for livestock, are used for turf and amenity purposes, and play a fundamental role in environment protection. Among cultivated grasses, species within the <it>Festuca-Lolium </it>complex predominate, especially in temperate regions. To facilitate high-throughput genome profiling and genetic mapping within the complex, we have developed a Diversity Arrays Technology (DArT) array for five grass species: <it>F. pratensis</it>, <it>F. arundinacea</it>, <it>F. glaucescens</it>, <it>L. perenne </it>and <it>L. multiflorum</it>.</p> <p>Results</p> <p>The DArTFest array contains 7680 probes derived from methyl-filtered genomic representations. In a first marker discovery experiment performed on 40 genotypes from each species (with the exception of <it>F. glaucescens </it>for which only 7 genotypes were used), we identified 3884 polymorphic markers. The number of DArT markers identified in every single genotype varied from 821 to 1852. To test the usefulness of DArTFest array for physical mapping, DArT markers were assigned to each of the seven chromosomes of <it>F. pratensis </it>using single chromosome substitution lines while recombinants of <it>F. pratensis </it>chromosome 3 were used to allocate the markers to seven chromosome bins.</p> <p>Conclusion</p> <p>The resources developed in this project will facilitate the development of genetic maps in <it>Festuca </it>and <it>Lolium</it>, the analysis on genetic diversity, and the monitoring of the genomic constitution of the <it>Festuca × Lolium </it>hybrids. They will also enable marker-assisted selection for multiple traits or for specific genome regions.</p

Structure of the dimeric N-glycosylated form of fungal β-N-acetylhexosaminidase revealed by computer modeling, vibrational spectroscopy, and biochemical studies

<p>Abstract</p> <p>Background</p> <p>Fungal β-<it>N</it>-acetylhexosaminidases catalyze the hydrolysis of chitobiose into its constituent monosaccharides. These enzymes are physiologically important during the life cycle of the fungus for the formation of septa, germ tubes and fruit-bodies. Crystal structures are known for two monomeric bacterial enzymes and the dimeric human lysosomal β-<it>N</it>-acetylhexosaminidase. The fungal β-<it>N</it>-acetylhexosaminidases are robust enzymes commonly used in chemoenzymatic syntheses of oligosaccharides. The enzyme from <it>Aspergillus oryzae </it>was purified and its sequence was determined.</p> <p>Results</p> <p>The complete primary structure of the fungal β-<it>N</it>-acetylhexosaminidase from <it>Aspergillus oryzae </it>CCF1066 was used to construct molecular models of the catalytic subunit of the enzyme, the enzyme dimer, and the <it>N</it>-glycosylated dimer. Experimental data were obtained from infrared and Raman spectroscopy, and biochemical studies of the native and deglycosylated enzyme, and are in good agreement with the models. Enzyme deglycosylated under native conditions displays identical kinetic parameters but is significantly less stable in acidic conditions, consistent with model predictions. The molecular model of the deglycosylated enzyme was solvated and a molecular dynamics simulation was run over 20 ns. The molecular model is able to bind the natural substrate – chitobiose with a stable value of binding energy during the molecular dynamics simulation.</p> <p>Conclusion</p> <p>Whereas the intracellular bacterial β-<it>N</it>-acetylhexosaminidases are monomeric, the extracellular secreted enzymes of fungi and humans occur as dimers. Dimerization of the fungal β-<it>N</it>-acetylhexosaminidase appears to be a reversible process that is strictly pH dependent. Oligosaccharide moieties may also participate in the dimerization process that might represent a unique feature of the exclusively extracellular enzymes. Deglycosylation had only limited effect on enzyme activity, but it significantly affected enzyme stability in acidic conditions. Dimerization and <it>N</it>-glycosylation are the enzyme's strategy for catalytic subunit stabilization. The disulfide bridge that connects Cys⁴⁴⁸with Cys⁴⁸³stabilizes a hinge region in a flexible loop close to the active site, which is an exclusive feature of the fungal enzymes, neither present in bacterial nor mammalian structures. This loop may play the role of a substrate binding site lid, anchored by a disulphide bridge that prevents the substrate binding site from being influenced by the flexible motion of the loop.</p

Internal audit control in the Czech National Health Insurance

Katedra finančního práva a finanční vědyDepartment of Financial Law and FinancesFaculty of LawPrávnická fakult

Evaluating of hyperelastic material behavior

Nowadays one of the most used method able to solve non-linear problems is finite-elemnt method. Mooney-Rivlin is the method describing the behaviour of hyperelastic materials with large elastic (reversible) deformations. The problem with the determining the hyperelastic materials' characteristics is one of the most important factors effecting the accuracy of the calculation result. The material's constants A and B are determined experimentally from the practical tests. This paper shows the possibility how to determinate these materials' characteristics and their verification with help of ABAQUS. The material coefficients of the hyperelastic models can be calibrated by ABAQUS from experimental stress-strain data. The material constants are determined through a least-squares-fit procedure, which minimizes the relative error in stress. We provided experimental data from uniaxial test for chosen material are used to have ABAQUS automatically determine appropriate values of the coefficients

Pracoviště pro měření antén

Measurements of test antennas are performed on antenna ranges. The operated microwave far-field outdoor range was built-up in 1970’s and therefore it was not appropriate for the today measurements. Thus, it was decided to perform the complete reconstruction and testing. Some results of new ample measurement campaign are just given. The optimization of antenna range using merely measurement is very inefficient, and therefore that is done by numerical simulations. Consequently the paper surveys briefly electromagnetic wave propagation over irregular terrain. The physical optics approximation of vector problem was chosen. That allows the comparison of selected numerical simulations and measurements for the reconstructed far-field range. A possibility of antenna range optimizing by using numerical simulation considering various constraints is verified.Měření se provádí na speciálním pracovišti. Pracoviště bylo vybudováno v sedmdesátých letech a proto se provedla kompletní rekonstrukce. Optimalizace se prováděla numericky

Optimalizace pracovičtě pro měření antén

Measurements of test antennas are performed on antenna ranges. The operated microwave far-field outdoor range was built-up in 1970’s and therefore it was not appropriate for the today measurements. Thus, it was decided to perform the complete reconstruction and testing. Some results of new ample measurement campaign are just given. The optimization of antenna range using merely measurement is very inefficient, and therefore that is done by numerical simulations. Consequently the paper surveys briefly electromagnetic wave propagation over irregular terrain. The physical optics approximation of vector problem was chosen. That allows the comparison of selected numerical simulations and measurements for the reconstructed far-field range. A possibility of antenna range optimizing by using numerical simulation considering various constrains is verified.Měření antén se provádělo na pracovišti ze sedmdesátých let a proto se rozhodlo o kompletní rekonstrukci. Optimalizace se prováděla pomocí fyzikální optiky numerickou simulací a různá omezení se verifikovala experimentálně