Workplace for testing of the photodiodes

Táto práca je zameraná na návrh a vytvorenie pracoviska vhodného na meranie základných parametrov a charakteristík bežných fotodiód. Súčasťou je experimentálne overenie jeho možností a porovnanie nameraných výsledkov s katalógovými hodnotami, ako aj vytvorenie programu na grafické spracovanie nameraných údajov.This paper is focused on design of the workplace for measuring basic parameters and characteristics of standard photodiodes. There is also experimental test of its possibilities and comparison of the measurement results with the catalogue data. It also includes elaboration of an algorithm that processes the measurement data into visual presentation.

Communication protocols for Free-Space Optical links

Táto diplomová práca sa zaoberá správaním protokolu TCP/IP pri prechode bezdrôtovým optickým spojom, ktorý je ovplyvnený atmosférickými turbulenciami. Tie spôsobujú fluktuáciu prijímaného optického výkonu a tým zmenu bitovej chybovosti spoja. Navrhnutý simulačný model využíva generovanie náhodnej úrovne prijímaného optického signálu a jeho prepočet na okamžitú bitovú chybovosť. Model je implementovaný do časovej analýzy sieťového simulátoru OMNeT++. Na základe simulácií je navrhnutá vyrovnávacia pamäť vo vysielači, ktorá pozastaví vysielanie v prípadoch výpadku linky. Metóda vyrovnávacej pamäte je realizovaná pomocou FPGA.This master’s thesis is focused on behaviour of the TCP/IP protocol on free-space optical link which is affected by the effect of atmospheric turbulence. This causes fluctuation of the received optical power and therefor bit error rate changes. In the simulation model short-time bit error rate is calculated from random generated received optical signal and then used in time-domain analysis of the OMNeT++ network simulator. A buffer in transmitter is designed based on simulation results. It pauses the data transmitting in cases of FSO link outage. This method is then implemented into FPGA device.

Architektura barbarů na Moravě v prvních staletích našeho letopočtu - stavební materiály, konstrukce a půdorysné dispozice

The article presents buildings representing architecture of the barbarian populations, which during the 1st-3rd century AD inhabited area of Moravia (Czech Republic) lying north of the Roman border on the Middle Danube. During archaeological excavations there were documented structures founded at the ground level, with pillars digged into the ground. There were used wooden structures with supporting elements in the form of stakes staffed in the ground, the walls were built using wicker and clay. There are known forms of large dimensions, but also small utility constructions. The surprising finding is fact, that when assessing the seemingly primitive recessed structures there were implemented measuring procedures requiring good knowledge of geometry and abillity to stake of right angles can be expected

Forward and Inverse Kinematics Using Pseudoinverse and Transposition Method for Robotic Arm DOBOT

Kinematic structure of the DOBOT manipulator is presented in this chapter. Joint coordinates and end-effector coordinates of the manipulator are functions of independent coordinates, i.e., joint parameters. This chapter explained forward kinematics task and issue of inverse kinematics task on the structure of the DOBOT manipulator. Linearization of forward kinematic equations is made with usage of Taylor Series for multiple variables. The inversion of Jacobian matrix was used for numerical solution of the inverse kinematics task. The chapter contains analytical equations, which are solution of inverse kinematics task. It should be noted that the analytical solution exists only for simple kinematic structures, for example DOBOT manipulator structure. Subsequently, simulation of the inverse kinematics of the above-mentioned kinematic structure was performed in the Matlab Simulink environment using the SimMechanics toolbox

Using of Virtual Instrumentation in the Teaching of Autotronics

This chapter presents using of virtual instrumentation for improvement of teaching and demonstration of communication of one of the most popular automotive buses CAN BUS. Virtual instrumentation is used in several ways for easier understanding of communication by using the automotive bus. The first way is a demonstration by visualization of data of programable gateway. The second way of using virtual instrumentation is the visualization of the instrument cluster which is controlled by the student’s development kit with the microprocessor. The visualization is also used for the demonstrational panel which consists of a development kit, instrument cluster, turbocharger, and accelerator pedal. The communication with these components is also visualized. The last usage of virtual instrumentation is controlling real instrument clusters from Skoda and VW vehicles using LabVIEW and CAN BUS interfaces. In both, controlling and visualizing of instrument cluster are used the same messages as in real vehicle, so it is easier for students to understand the structure of communication through automotive buses of the real vehicle

Efficient and robust preparation of tyrosine phosphorylated intrinsically disordered proteins

Intrinsically disordered proteins (IDPs) are subject to post-translational modifications. This allows the same polypeptide to undertake different interaction networks with different consequences, ranging from regulatory signalling networks to formation of membraneless organelles. We report a robust method for co-expression of modification enzyme and SUMO-tagged IDP with subsequent purification procedure allowing production of modified IDP. The robustness of our protocol is demonstrated on a challenging system, RNA polymerase II C-terminal domain (CM), that is a low-complexity repetitive region with multiple phosphorylation sites. In vitro phosphorylation approaches fail to yield multiple-site phosphorylated CTD, whereas our in vivo protocol allows to rapidly produce near homogeneous phosphorylated CTD at a low cost. These samples can be used in functional and structural studies

Achromobacter marplatensis sp. nov., isolated from a pentachlorophenol contaminated soil

A polyphasic taxonomic approach was applied to the study of a Gram-negative bacterium (B2T) isolated from soil by selective enrichment with pentachlorophenol. 16S rRNA gene sequence analysis of strain B2T showed that the strain belongs to the genus Achromobacter within the Betaproteobacteria. The 16S rRNA gene sequence displayed more than 99 % similarity to the sequences of the type strains of all species of Achromobacter, with the highest sequence similarity to those of Achromobacter spanius CCM 7183T and A. piechaudii CCM 2986T (99.8 %). On the basis of phylogenetic analysis, genomic DNA–DNA relatedness and phenotypic characteristics, including chemotaxonomic (cellular fatty acid profile) analysis, a novel species is proposed, Achromobacter marplatensis sp. nov., with the type strain B2T ( = CCM 7608T = CCUG 56371T = CECT 7342T)

Staphylococcus aureus Prophage-Encoded Protein Causes Abortive Infection and Provides Population Immunity against Kayviruses

Both temperate and obligately lytic phages have crucial roles in the biology of staphylococci. While superinfection exclusion among closely related temperate phages is a well-characterized phenomenon, the interactions between temperate and lytic phages in staphylococci are not understood. Here, we present a resistance mechanism toward lytic phages of the genus Kayvirus, mediated by the membrane-anchored protein designated PdpSau encoded by Staphylococcus aureus prophages, mostly of the Sa2 integrase type. The prophage accessory gene pdpSau is strongly linked to the lytic genes for holin and ami2-type amidase and typically replaces genes for the toxin Panton-Valentine leukocidin (PVL). The predicted PdpSau protein structure shows the presence of a membrane-binding a-helix in its N-terminal part and a cytoplasmic positively charged C terminus. We demonstrated that the mechanism of action of PdpSau does not prevent the infecting kayvirus from adsorbing onto the host cell and delivering its genome into the cell, but phage DNA replication is halted. Changes in the cell membrane polarity and permeability were observed from 10 min after the infection, which led to prophage-activated cell death. Furthermore, we describe a mechanism of overcoming this resistance in a host-range Kayvirus mutant, which was selected on an S. aureus strain harboring prophage 53 encoding PdpSau, and in which a chimeric gene product emerged via adaptive laboratory evolution. This first case of staphylococcal interfamily phage-phage competition is analogous to some other abortive infection defense systems and to systems based on membrane-destructive proteins. IMPORTANCE Prophages play an important role in virulence, pathogenesis, and host preference, as well as in horizontal gene transfer in staphylococci. In contrast, broad-host-range lytic staphylococcal kayviruses lyse most S. aureus strains, and scientists worldwide have come to believe that the use of such phages will be successful for treating and preventing bacterial diseases. The effectiveness of phage therapy is complicated by bacterial resistance, whose mechanisms related to therapeutic staphylococcal phages are not understood in detail. In this work, we describe a resistance mechanism targeting kayviruses that is encoded by a prophage. We conclude that the defense mechanism belongs to a broader group of abortive infections, which is characterized by suicidal behavior of infected cells that are unable to produce phage progeny, thus ensuring the survival of the host population. Since the majority of staphylococcal strains are lysogenic, our findings are relevant for the advancement of phage therapy

Celtic mercenaries in the military services of the medditerranean states and their homecoming to the countries of the Middle Europe

Activities of the Celtic mercenaries in the Mediterranean environment are surprisingly often mentioned by the ancient writers. They used to appear in services for authorities there, in the Near East, “Magna Graecia” and other parts of southern Europe and also in Egypt or Carthage. They completed armies of the states fighting each other or against the Roman republic when they joined the fighting for domination in this area, and the last troops were still in service during the last decades before the change of the era. The findings discovered during the archaeological research, mainly coins that had been produced in the Mediterranean area and which appear in the Middle Europe (Roseldorf, Němčice nad Hanou, Nowa Cerekwia) led to a hypothesis that some of the mercenaries returned to these places after finishing their service. The article comes up with arguments enabling a support for such hypotheses