Technology of resurfacing Mn-steels used to manufacture rails

The track components that are the most heavily loaded from the axles of train units are the switch components and rail crossing parts. These parts can be refurbished by welding on suitable types of additional materials. Parts made of high alloyed Mn-steel (Hadfield steels) need to meet specific conditions for their welding. For the experiment, ESAB OK Tubrodur 14.71 and ESAB OK Tubrodur 15.65 materials were used. The results show the feasibility of appropriate procedures under specific conditions due to the occurrence of metallurgical defects affecting the safety of operation on railway and tram lines. The aim of the experiment was to perform and assess the properties of two types of austenitic welds of different chemical composition on the rail head and rail grooves with the same welding parameters.Web of Science20236384638

P53 binds preferentially to non-B DNA structures formed by the pyrimidine-rich strands of GaA·TTC trinucleotide repeats associated with Friedreich’s ataxia

Expansions of trinucleotide repeats (TNRs) are associated with genetic disorders such as Friedreich’s ataxia. The tumor suppressor p53 is a central regulator of cell fate in response to different types of insults. Sequence and structure-selective modes of DNA recognition are among the main attributes of p53 protein. The focus of this work was analysis of the p53 structure-selective recognition of TNRs associated with human neurodegenerative diseases. Here, we studied binding of full length p53 and several deletion variants to TNRs folded into DNA hairpins or loops. We demonstrate that p53 binds to all studied non-B DNA structures, with a preference for non-B DNA structures formed by pyrimidine (Py) rich strands. Using deletion mutants, we determined the C-terminal DNA binding domain of p53 to be crucial for recognition of such non-B DNA structures. We also observed that p53 in vitro prefers binding to the Py-rich strand over the purine (Pu) rich strand in non-B DNA substrates formed by sequence derived from the first intron of the frataxin gene. The binding of p53 to this region was confirmed using chromatin immunoprecipitation in human Friedreich’s ataxia fibroblast and adenocarcinoma cells. Altogether these observations provide further evidence that p53 binds to TNRs’ non-B DNA structures

Generated heat by different targets irradiated by 660 MeV protons

Calorimetric experiments have been performed to analyze different thick targets of natU, C, Pb material, irradiated by 660 MeV protons at the Phasotron accelerator facility, Joint Institute for Nuclear Research (JINR) in Dubna, Russia. The method of online temperature measurement has been compared with MCNPX 2.7.0 simulation and selected with Ansys Transient Thermal Simulation to compare measured temperature with the simulated one. Thermocouples type T and E have been used as a temperature probe. Many different positions have been measured for each target. Temperature results are following very well the processes inside of the cylinders. Changes of heat deposition caused by drops of the proton beam intensity are displayed very well as a jagged line shown in almost every chart. Accurate temperature changing measurement is a very modest variation of how to observe inner macroscopic behavior online

Vladislav Vančura v literárním kontextu 20. století

Title in English: Vladislav Vančura in the Literary Context of the 20th Century On June 23, 2021, it was the 130th anniversary of Vladislav Vančura’s birth, and June 1, 2022, was the 80th anniversary of his death. These anniversaries became the impetus for a collective volume entitled Vladislav Vančura in the Literary Context of the 20th Century. The editor Jiří Poláček approached researchers from various disciplines from literary studies to linguistics and to theatre studies with an appeal to think and rethink the literary and general cultural legacy of this important figure. The book volume by the team of researchers from six Czech universities is an attempt to reflect on the oeuvre by Vančura from the perspective of the current state of knowledge in literary studies and the broader context of the 20th century. The image of Vladislav Vančura within the context of the previous century arises from 15 texts by 15 authors, organized into four thematic blocks

Experimental investigation and Monte Carlo simulations of radionuclide production inside the Uranium spallation target QUINTA irradiated with a 660-MeV proton beam

The accelerator-Driven-System (ADS) is very important to study the neutron field and radionuclide production inside simple-geometry uranium subcritical setups irradiated with high energy particle beams. A subcritical setup QUINTA was irradiated with the 660-MeV proton beam from Phasotron accelerator at the Joint Institute for Nuclear Research (JINR). The radionuclide production in the region along the beam axis was investigated by the activation technique. The aim was to compare (n,x) with (p,x) reactions using activation detectors of 59Co and natPb, and compare experimental results with the calculated results using Monte Carlo simulation code MCNPX 2.7

Plant Diversity Changes during the Postglacial in East Asia: Insights from Forest Refugia on Halla Volcano, Jeju Island

Understanding how past climate changes affected biodiversity is a key issue in contemporary ecology and conservation biology. These diversity changes are, however, difficult to reconstruct from paleoecological sources alone, because macrofossil and pollen records do not provide complete information about species assemblages. Ecologists therefore use information from modern analogues of past communities in order to get a better understanding of past diversity changes. Here we compare plant diversity, species traits and environment between late-glacial Abies, early-Holocene Quercus, and mid-Holocene warm-temperate Carpinus forest refugia on Jeju Island, Korea in order to provide insights into postglacial changes associated with their replacement. Based on detailed study of relict communities, we propose that the late-glacial open-canopy conifer forests in southern part of Korean Peninsula were rich in vascular plants, in particular of heliophilous herbs, whose dramatic decline was caused by the early Holocene invasion of dwarf bamboo into the understory of Quercus forests, followed by mid-Holocene expansion of strongly shading trees such as maple and hornbeam. This diversity loss was partly compensated in the Carpinus forests by an increase in shade-tolerant evergreen trees, shrubs and lianas. However, the pool of these species is much smaller than that of light-demanding herbs, and hence the total species richness is lower, both locally and in the whole area of the Carpinus and Quercus forests. The strongly shading tree species dominating in the hornbeam forests have higher leaf tissue N and P concentrations and smaller leaf dry matter content, which enhances litter decomposition and nutrient cycling and in turn favored the selection of highly competitive species in the shrub layer. This further reduced available light and caused almost complete disappearance of understory herbs, including dwarf bamboo

TRY plant trait database – enhanced coverage and open access

Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Acoustick Emission Measurement

Import 11/07/2012Cílem této diplomové práce je seznámit se s principem metody akustické emise, která se používá pro nalezení možných vad materiálu, vznikajících namáháním, a navrhnout a realizovat zařízení pro její měření. Zařízení bude pracovat na bázi programovatelných hradlových polí Actel s procesorovým jádrem a s Ethernet rozhraním pro komunikaci s nadřízeným systémem. K realizaci bylo vybráno hradlové pole rodiny SmartFusion ve spolupráci s procesorem Cortex-M3. Pro implementaci logických obvodů do tohoto pole bylo využito vývojové prostředí Libero IDE. Toto prostředí, jehož součástí je i simulátor ModelSim, pomocí kterého si ověříme funkčnost návrhu, poskytuje rovněž firma Actel. Pro popis hardwarových struktur hradlových polí byl použit programovací jazyk VHDL a pro naprogramování procesoru programovací jazyk C a vývojové prostředí SoftConsole IDE. Věřím, že má diplomová práce splní svůj účel, osvětlí problematiku akustické emise a srozumitelně vysvětlí mnou zvolený způsob realizace tohoto systému.The aim of this thesis is to introduce the principle of the method of acoustic emission and to design facilities for its measurement. This method is used for discovering potential material defects caused by stressing it. The device will operate on the basis of Actel programmable gate arrays with processor core and Ethernet interface for communication with host system. Gate array of SmartFusion family in collaboration with Cortex-M3 processor was chosen for the implementation. Actel company also provides the development environment Libero IDE which was used to implement the logic circuits into this array. This development environment includes the Model Sim simulator which enables the design functionality testing. Two programming languages were used: VHDL for the description of the hardware structure and C with SoftConsole IDE for CPU programming. I believe that this thesis has fulfilled its purpose, clarifies issues of acoustic emission and clearly explains my chosen method of the system implementation.460 - Katedra informatikyvýborn

Možnosti opakované renovace kolejnic navařováním

Import 20/04/2006Prezenční výpůjčkaVŠB - Technická univerzita Ostrava. Fakulta strojní. Katedra (345) mechanické technologi