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Computer design of a digital radio link
Havel, Ladislav ; Nováček, Zdeněk (referee) ; Láčík, Jaroslav (advisor)
The Terrestrial digital radio links are used for transmitting digital information between fixed stations on a line of sight of a radio path. Each digital radio link has many characteristics and parameters for transmission. We require technical parameters in the design of digital radio link such as data rates and capacities. In this design we should take into account most effects of the electromagnetic waves propagation, if we want to meet user technical requirements of the link and if that link may correctly transmit digital signals with minimum errors. Prediction methods for the design of terrestrial line of sight systems are still in progress. Some effects of electromagnetic waves propagation and methods of the digital radio link design depend on natural variability and climate. The goal of this diploma thesis is to investigate methods for the design of terrestrial line of sight links with taking into account of ITU recommendation. Make computer program which implement this investigate methods
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Cell cycle regulation in plants: the role of CDK activatory dephosphorylation at entry into mitosis
Mašková, Petra ; Macháčková, Ivana (advisor) ; Havel, Ladislav (referee) ; Vaňková, Radomíra (referee)
t I I I I I I I I I I I I I I Summary of PhD. thesis Cel1 division representsone of fundamentalattributesof all living creatuÍes.Basic molecular mechanisms operating during cell proliferation seem to be evolutionary conservedamongeukaryotes.The cell cycle is dividedin four subsequentphases;themost regulatoryeventsareconcentratedin Gr/S andGzlM checkpoints. The key regulatory proteins, cyclin-dependentkinases (CDKs), govern the progress throughthe whole cell cycle. Their function is strictly dependenton catalytic cyclin subunits.The correspondingcyclin partnerbinding CDK determinesthe time window of the specific CDlVcyclin complex actionin individual cell cycle phase.To becomefully active, the complex requiresfurtherposttranslationalmodificationincluding activatory phosphorylationanddephosphorylationof theCDK on specificaminoacidresidues. Plant cell cycle, besideswell-conservedmechanismscoÍlmonto all eukaryotes,exhibits other specific mechanismsresultingfrom plant survival strategy.The Gr/S transitionis stronglyaffectedby extemalandinternalsignals,mainlyphytohormonesandmetabolites, reflectingthe elementaryconditionssuitablefor accomplishmentof the whole cell cycle. The centralmoleculerespondingto thesesignalsat Gr/S is D cyclin, whoseexpressionis regulatedby cýokinin and sucrose(Riou-Khamlichi et aI.,...
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Characterization of the role of cytokinins and abscisic acid during abiotic stress response
Přerostová, Sylva ; Vaňková, Radomíra (advisor) ; Havel, Ladislav (referee) ; Doležal, Karel (referee)
Abiotic stresses significantly reduce crop yield, causing serious problems in agriculture. Understanding the mechanisms of plant stress responses could contribute to the improvement of their stress tolerance. Phytohormones play an important role in plant stress defence as well as in regulation of growth and development. This thesis summarizes the results published in four articles focused on the evaluation of the effects of phytohormones during abiotic stresses, namely salinity, drought, ZnO nanoparticle treatment and cold stress. The main emphasis is put on abscisic acid as the key regulator of water status and stress defence, and on cytokinins, which regulate plant growth and stabilize photosynthetic machinery. Cytokinins act antagonistically to abscisic acid. Our results showed that abscisic acid is a general abiotic stress response regulator. Stress- tolerant plants (halophyte Thellungiella salsuginea or winter line of einkorn wheat Triticum monococcum) had a higher basal level of this hormone, especially in shoot meristematic tissues (apices, crowns), than stress-sensitive plants. Stress-tolerant plants reacted faster and in a more flexible way to stress. Active cytokinins were negatively affected by stress, which was associated with growth suppression. The drought stress study showed that...
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Study of the function of the hybrid proline-rich protein family
Dvořáková, Lenka ; Fischer, Lukáš (advisor) ; Vágner, Martin (referee) ; Havel, Ladislav (referee)
Lenka Dvořáková SUI'^,ÍARYoF TřE PH.D. TFDSIS 4. CONCLUSIONS Ancestral HyPRP evolved probably from a lipid transfer protein (LTP) relative that had acquired a sequence encoding a long proline-rich N-terminal domain. The origin of HyPRPs may be one of the evolutionary innovationsof seedplants. Specific sequence is not probably important for formation of the functional 8 CM domain of HyPRPs with exception of eight conserved cysteine residues.which stabilize the tertiary structureof the domain. HyPRPs with long proline-rich N-terminal domains are relatively well-conserved and probably evolutionary more original. Proteins with aýpical N-terminal domains (very short. glycine-rich) evolved apparently relatively recently and independentlyin differentplant speciespossibly by means of shortening, loss or re€uTangements of the ancestral longer proline-rich domains. Glycine-rich domains could originate from proline-rich ones by way of inversion in the coding sequence.This mechanismcould have greatimpact in evolution of cell wall proteins in general, becausethey are often rich eitherin prolineor glycine. N-terminal domains of angiosperm C-type HyPRPs remained relatively well conserved (long and hydrophobic), while the rest of angiosperm HyPRPs has been undergoing rapid and continuous diversification. However, in the...
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Characterization of the role of cytokinins and abscisic acid during abiotic stress response
Přerostová, Sylva ; Vaňková, Radomíra (advisor) ; Havel, Ladislav (referee) ; Doležal, Karel (referee)
Abiotic stresses significantly reduce crop yield, causing serious problems in agriculture. Understanding the mechanisms of plant stress responses could contribute to the improvement of their stress tolerance. Phytohormones play an important role in plant stress defence as well as in regulation of growth and development. This thesis summarizes the results published in four articles focused on the evaluation of the effects of phytohormones during abiotic stresses, namely salinity, drought, ZnO nanoparticle treatment and cold stress. The main emphasis is put on abscisic acid as the key regulator of water status and stress defence, and on cytokinins, which regulate plant growth and stabilize photosynthetic machinery. Cytokinins act antagonistically to abscisic acid. Our results showed that abscisic acid is a general abiotic stress response regulator. Stress- tolerant plants (halophyte Thellungiella salsuginea or winter line of einkorn wheat Triticum monococcum) had a higher basal level of this hormone, especially in shoot meristematic tissues (apices, crowns), than stress-sensitive plants. Stress-tolerant plants reacted faster and in a more flexible way to stress. Active cytokinins were negatively affected by stress, which was associated with growth suppression. The drought stress study showed that...
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Cell cycle regulation in plants: the role of CDK activatory dephosphorylation at entry into mitosis
Mašková, Petra ; Macháčková, Ivana (advisor) ; Havel, Ladislav (referee) ; Vaňková, Radomíra (referee)
t I I I I I I I I I I I I I I Summary of PhD. thesis Cel1 division representsone of fundamentalattributesof all living creatuÍes.Basic molecular mechanisms operating during cell proliferation seem to be evolutionary conservedamongeukaryotes.The cell cycle is dividedin four subsequentphases;themost regulatoryeventsareconcentratedin Gr/S andGzlM checkpoints. The key regulatory proteins, cyclin-dependentkinases (CDKs), govern the progress throughthe whole cell cycle. Their function is strictly dependenton catalytic cyclin subunits.The correspondingcyclin partnerbinding CDK determinesthe time window of the specific CDlVcyclin complex actionin individual cell cycle phase.To becomefully active, the complex requiresfurtherposttranslationalmodificationincluding activatory phosphorylationanddephosphorylationof theCDK on specificaminoacidresidues. Plant cell cycle, besideswell-conservedmechanismscoÍlmonto all eukaryotes,exhibits other specific mechanismsresultingfrom plant survival strategy.The Gr/S transitionis stronglyaffectedby extemalandinternalsignals,mainlyphytohormonesandmetabolites, reflectingthe elementaryconditionssuitablefor accomplishmentof the whole cell cycle. The centralmoleculerespondingto thesesignalsat Gr/S is D cyclin, whoseexpressionis regulatedby cýokinin and sucrose(Riou-Khamlichi et aI.,...
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Study of polyamine metabolism in cell division and their role in physiological plant processes
Gemperlová, Lenka ; Cvikrová, Milena (advisor) ; Šebela, Marek (referee) ; Havel, Ladislav (referee)
3. AIMS To study the role of PA biosynthesis,oxidation and conjugation in maintenanceof free intracellular PA levelsduring the growth and cell cycle of tobacco BY-2 cell culture (Nicotiana tabacum L.cv. Bright Yellow-2). Partial aims: o To describe alterations in the levels of free PA and PA conjugated with HCA during the growth and cell cycle oftobaccoBY-2 cell culture. o To charaďerjzechangesin the activities of PA bioqynthetic en4/mes(ADC, ODC and SAMDC) during the growth and cell cycle oftobacco BY-2 cell culture. o To detenrrinatechangesin the activiý of PA degradation en4fme (DAO) duringthegrowthandcell cycle of tobacco BY-2 cell culture. Following (next)aims: o To evaluatealterationsin the levels of intracellular free and conjugatedPA in tobacco BY-2 cell culture under Cd2*- inducedoxidativestress. o To studythemechanismsof PA homeostasis(biosynthesis, degradation and conjugation) during the diurnal cycle oftobacco plant(Nicotiana tabacumL. cv. Wisconsin 38). o To evaluate the role of excreted PA in PA homeostasis dwing the growth cycle of tobacco BY-2 and alfalfa (MedicagosativaL.) cell suspensionculture. o To comparechangesin the PA metabolismduring somatic and zygotic embryodevelopmentof Norway spruce(Picea abiesL. (Kars|). 7
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Study of the function of the hybrid proline-rich protein family
Dvořáková, Lenka ; Fischer, Lukáš (advisor) ; Vágner, Martin (referee) ; Havel, Ladislav (referee)
Lenka Dvořáková SUI'^,ÍARYoF TřE PH.D. TFDSIS 4. CONCLUSIONS Ancestral HyPRP evolved probably from a lipid transfer protein (LTP) relative that had acquired a sequence encoding a long proline-rich N-terminal domain. The origin of HyPRPs may be one of the evolutionary innovationsof seedplants. Specific sequence is not probably important for formation of the functional 8 CM domain of HyPRPs with exception of eight conserved cysteine residues.which stabilize the tertiary structureof the domain. HyPRPs with long proline-rich N-terminal domains are relatively well-conserved and probably evolutionary more original. Proteins with aýpical N-terminal domains (very short. glycine-rich) evolved apparently relatively recently and independentlyin differentplant speciespossibly by means of shortening, loss or re€uTangements of the ancestral longer proline-rich domains. Glycine-rich domains could originate from proline-rich ones by way of inversion in the coding sequence.This mechanismcould have greatimpact in evolution of cell wall proteins in general, becausethey are often rich eitherin prolineor glycine. N-terminal domains of angiosperm C-type HyPRPs remained relatively well conserved (long and hydrophobic), while the rest of angiosperm HyPRPs has been undergoing rapid and continuous diversification. However, in the...
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