The master thesis analyzes the Act No. 234/2014 Coll., On Civil Service, from the aspect of related legislation, Act No. 312/2002 Coll., On Public Officials of the Local Self-Government Units. When ...the Law On the Civil Service came into force, at the beginning of last year, two categories of officials were created. On the one side there are civil servants who are in service of the Czech Republic, on the other side there are officials who are employed by local self-government units. The analysis is focused on five areas, where it is possible to compare the method of legislation under both laws. After review of these selected areas, the application problems of the civil service are identified. At the end of the thesis, there are legislative proposals for changes that are inspired by relevant legislation.
Spiders are an ancient and extremely diverse animal order. They show a considerable diversity of genome sizes, karyotypes and sex chromosomes, which makes them promising models to analyse the ...evolution of these traits. Our study is focused on the evolution of the genome and chromosomes in haplogyne spiders with holokinetic chromosomes. Although holokinetic chromosomes in spiders were discovered a long time ago, information on their distribution and evolution in these arthropods is very limited. Here we show that holokinetic chromosomes are an autapomorphy of the superfamily Dysderoidea. According to our hypothesis, the karyotype of ancestral Dysderoidea comprised three autosome pairs and a single X chromosome. The subsequent evolution has frequently included inverted meiosis of the sex chromosome and an increase of 2n. We demonstrate that caponiids, a sister clade to Dysderoidea, have enormous genomes and high diploid and sex chromosome numbers. This pattern suggests a polyploid event in the ancestors of caponiids. Holokinetic chromosomes could have arisen by subsequent multiple chromosome fusions and a considerable reduction of the genome size. We propose that spider sex chromosomes probably do not pose a major barrier to polyploidy due to specific mechanisms that promote the integration of sex chromosome copies into the genome.
Abstract
Previous studies suggested that holocentric chromosomes may confer a selective advantage under high ionizing or UV-B radiation due to their tolerance of fragmentation, and that the first ...plant and animal colonizers of land in the Palaeozoic were or may have been holocentric. Holocentric chromosomes could have, therefore, aided terrestrialization of Earth’s biota half a billion years ago, because leaving water meant facing a sharp increase of UV-B. Because we cannot go back in time, the hypothesis needs to be tested with present-day species using an indicator of UV-B stress. We took advantage of the fact that UV-B intensity increases with elevation and tested whether holocentric plants (six species of Cyperaceae and Juncaceae) are less stressed with increasing elevation than monocentric plants (six species of Poaceae). Phylogenetically corrected regression showed that the proxy for UV-B stress (endopolyploidy index from 671 samples measured by flow cytometry) increased with elevation in holocentric and monocentric species, but the increase was more rapid in monocentric species. Although half a billion year elapsed since terrestrialization, holocentric Cyperaceae and Juncaceae still appear less stressed by UV-B than monocentric Poaceae, despite the other counter UV-B adaptations they both have evolved (graminoid morphology, silica bodies).
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Holocentric chromosomes have evolved in various plant and animal taxa, which suggests they may confer a selective advantage in certain conditions, yet their adaptive potential has scarcely been ...studied. One of the reasons may reside in our insufficient knowledge of the phylogenetic distribution of holocentric chromosomes across eukaryotic phylogeny. In the present study, we focused on Droseraceae, a carnivorous plant family with an unknown chromosomal structure in monotypic genera Dionaea andAldrovanda, and a closely related monotypic family Drosophyllaceae. We used flow cytometry to detect holocentric chromosomes by measuring changes in the ratio of the number of G2 nuclei to the number of G1 nuclei in response to gamma irradiation and determined chromosomal structures in Aldrovanda vesiculosa, Dionaea muscipula, Drosera tokaiensis, and Drosera ultramafica from Droseraceae and Drosophyllum lusitanicum from Drosophyllaceae. We confirmed monocentric chromosomes in D. Lusitanicum and detected holocentric chromosomes in all four Droseraceae. Our novel finding of holocentric chromosomes in monotypic genera Aldrovanda and Dionaea suggests that all Droseraceae may be holocentric, but to confirm that further research is needed due to previously reported conflicting results in Drosera rotundifolia.
Iron modified zeolites represent interesting group of catalysts suitable for organic compounds removal from waste streams. In this work the MFI structured catalysts with various Fe contents ...incorporated by isomorphous substitution were prepared hydrothermally using two methods with different sources of silica and iron. The structure of the catalysts was tested by XRD, contents of Fe were determined by XRF, Fe centers were characterized by UV–Vis spectroscopy, and BET isotherms were used for porosity measurements. Iron silicate MFI catalysts were used in catalytic phenol removal from water by wet peroxide oxidation in batch arrangement. Catalysts with at least 1% of Fe provided full phenol conversion after 5 h of reaction.
•Temperature distribution in medium fire compartment is investigated experimentally.•Numerical simulation of the travelling fire test is completed by using FDS.•Measurements from the travelling fire ...test are used to validate the simulation.•Travelling fire is compared to compartment fire with uniform temperature conditions.•A potential impact of temperature heterogeneity on a structure is highlighted.
In order to follow modern trends in contemporary building architecture which is moving off the limits of current fire design models, assumption of homogeneous temperature conditions used for structural fire analysis needs to be validated. In this paper it is described, how temperature distribution in a medium-size fire compartment has been investigated experimentally by conducting fire test in two-storey experimental building in September 2011 in the Czech Republic. In the upper floor, a scenario of travelling fire was prepared. It has been observed that as flames were spreading across the compartment, considerable temperature gradients appeared. Numerical simulation of the travelling fire test conducted using FDS (Fire Dynamics Simulator) has been compared with simulation of compartment fire under uniform temperature conditions to highlight the potential impact of the gas temperature heterogeneity on structural behaviour. The temperature measurements from the fire test have been used for validation of the numerical simulation of travelling fire. The fire test has provided important data for design model of travelling fire and shown that its impact on structural behaviour is not in agreement with the assumption of homogenous temperature conditions.
Enteroviruses, members of the family of picornaviruses, are the most common viral infectious agents in humans causing a broad spectrum of diseases ranging from mild respiratory illnesses to ...life-threatening infections. To efficiently replicate within the host cell, enteroviruses hijack several host factors, such as ACBD3. ACBD3 facilitates replication of various enterovirus species, however, structural determinants of ACBD3 recruitment to the viral replication sites are poorly understood. Here, we present a structural characterization of the interaction between ACBD3 and the non-structural 3A proteins of four representative enteroviruses (poliovirus, enterovirus A71, enterovirus D68, and rhinovirus B14). In addition, we describe the details of the 3A-3A interaction causing the assembly of the ACBD3-3A heterotetramers and the interaction between the ACBD3-3A complex and the lipid bilayer. Using structure-guided identification of the point mutations disrupting these interactions, we demonstrate their roles in the intracellular localization of these proteins, recruitment of downstream effectors of ACBD3, and facilitation of enterovirus replication. These structures uncovered a striking convergence in the mechanisms of how enteroviruses and kobuviruses, members of a distinct group of picornaviruses that also rely on ACBD3, recruit ACBD3 and its downstream effectors to the sites of viral replication.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The paper presents fire test and numerical simulation results of temperature distributions in reverse channel connections to concrete-filled tubular columns during standard and natural fire tests. ...The experiments included a furnace fire test with the composite frame subjected to increasing fire temperature according to the ISO 834 standard time–temperature curve and two natural fire tests in a full-scale structure including a cooling phase. These fire tests examined the effects of fire protection, different connection locations and different connection dimensions. Temperatures at different connection components were recorded. The recorded connection component temperatures were simulated by using the SAFIR fire engineering software to calibrate the thermal boundary conditions in different connection components. From the numerical simulation results, it has been concluded that radiation to the inner surfaces of the reverse channel and the adjacent part of the column tube is only from the gas volume bounded by these surfaces. A lower flame emissivity value than the standard value should be used. For simplicity, a value of εf=0.1 is proposed. Also a lower value of the convective heat transfer coefficient of 10W/m2K can be used in the connection area.
•Temperature of bolts, end plate and reverse channel may be considered as uniform.•Temperature of column tube and adjacent welds is influenced by column concrete core.•Gas volume enclosed by reverse channel surface is used to calculate gas emissivity.•For simplicity, proposed gas emissivity for connection inner surfaces is εf=0.1.•Convective heat transfer coefficient of 10W/m2K can be used in connection area.
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