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Safety of operation of construction machines
Procházka, Radek ; Kašpárek, Jaroslav (referee) ; Škopán, Miroslav (advisor)
This thesis deals with the major security risks in the operation of construction machines with regard to the nature of the work of the individual assemblies. There is also present an overview of the risks associated with the technology works. The work is divided into four parts and is developed on the basis of lessons learned in the form of a technical report for training workers for construction machinery in the area of safety. The first part deals with a general overview of work safety in the construction machinery sector in terms of the applicable laws of the Czech Republic. In the second part contained the main risks and safety in terms of individual groups of earthmoving machines according to valid standards. In the third part of the processing analysis of the major risks in the operation of construction machines and work safety. In the fourth schedule of all the important knowledge and prepare a draft methodological guide for training operators of earthmoving machines in terms of safety.
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The role of microRNAs in regulation of mammalian oocyte and embryo development
Marcollová, Kateřina ; Procházka, Radek (advisor) ; Svoboda, Petr (referee)
Cumulus-oocyte complex (COCs) is crucial for mammalian reproduction. Cumulus cells not only nurture the oocyte; they also represent important communicational nodes for mediating information towards and from the oocyte. The non-coding miRNAs can modulate posttranscriptional events they might serve as a useful biomarker for evaluating cell conditions. Based on the COCs staining with vital Lissamine Green B stain we divided cumulus cells into high- and low-quality ones. Furthermore, we implemented division based on the maturation stage, the GV and MII. Sequencing data analysis showed that DE miRNAs from qualitatively different stages donot significantly vary. Nonetheless, significantly DE miRNAs were detected between two developmentally different stages. We identified e.g. ssc-miR-183, ssc-miR-182, and ssc-miR-21-5p to be highly downregulated when comparing GV to MII stage. Among the highly expressed miRNAs from all samples were members of let-7 family (let-7c, let-7a, let- 7f-5p), ssc-miR-16, ssc-miR-21-5p, and ssc-miR-125a. Targeted genes by the DE miRNAs were involved in ErbB, TGF-β, MAPK, FoxO, gap junction and cGMP signalling pathways. We conclude that single miRNAs in cumulus cells probably cannot be used as a reliable oocyte quality marker. On the other hand,changes in the miRNA expression in...
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Effect of sperm ubiquitination in early embryonic development of porcine embryos
Petelák, Aleš ; Krylov, Vladimír (advisor) ; Šušor, Andrej (referee) ; Procházka, Radek (referee)
The PhD thesis is focused on the effect of porcine sperm cell extracellular ubiquitination on early embryonic development up to the blastocyst stage after ICSI. In addition, it also presents a potential improvement of the technique of in vitro fertilization using oocyte incubation with ion channels regulators. To address these aims, we established an entirely novel methodology for sperm cell sorting using flow cytometry and subsequent cryopreservation. We determined the conditions for successful sperm cell sorting based on extracellular ubiquitination rate providing highly specific selection as well as sufficient numbers of viable sperms for fertilization using the ICSI method. Concerning the following cryopreservation, established methods were optimized to enable freezing of a minimal sperm cell suspension volume with low cell numbers. The performed experiments showed a direct relationship between the rate of extracellular ubiquitination and the capability of sperms to give rise to a properly developing embryo. Highly ubiquitinated sperm cells were less successful regarding the embryonic development to the blastocyst stage if compared with the lowly ubiquitinated group (6,2 % vs. 16,7 %, P<0,001). Interestingly, the rate of extracellular ubiquitination showed no effect on the pronuclear formation...
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Faktoring jako nástroj optimalizace řízení pohledávek malých automobilových dopravců
Procházka, Radek
Each company must deal how to resolve funding of business activities. One option could be factoring. Client gains funds as well as administration of receivables. The aim of my disertation is prove whether factoring contribued to financial stability of selected companies.There is a Financial analysis in the practical part of my disertation. You can find business´s conditions before and after using factoring. I compared the costs of factorng and costs of operating credit. Statistical verification was performed. Finally, suggestions and recommendations are specified.
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The role of growth factors and cytokines in regulation of mammalian oocyte maturation
Marcollová, Kateřina ; Procházka, Radek (advisor) ; Vávra, Jiří (referee)
Reproduction is key for species survival. Oocytes are blocked in prophase I of meiosis in follicle. Gonadotropin stimulation leads to follicle growth and competent oocyte. First polar body extrusion is a sign of meiotic division resumption. Oocyte is blocked at prophase I by a high cAMP level, activating PKA, that inhibits MPF. CNP binds to NPR2, that stimulates the generation of cGMP in granulosa cells, which diffuses to oocyte where it competes with cAMP on PDE3A. LH and FSH released from pituitary gland initiates signaling cascade restoring meiotic division. Synthesis of AREG, EREG and BTC activates EGFR and MAPK pathways in somatic cells which contribute to reduction of gap junction permeability, lowering NPR2 activity, that leads to reduction of cGMP production and transport. Less cGMP diffuses to oocytes, which leads to PDE3A activation and cAMP hydrolysis. This causes MPF activation and meiotic division resumption. MAPK together with PI3K participate on increasing production of hyaluronic acid, thereby cumulus cells expansion and oocyte ovulation. Oocyte maturation and growth is improved with utilization of in vitro technics and oocyte cultivation with growth factors and cytokines. FLI medium, combining FGF2, LIF and IGF-1, increases oocyte cultivation success and blastocyst quality of farm...
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Effect of sperm ubiquitination in early embryonic development of porcine embryos
Petelák, Aleš ; Krylov, Vladimír (advisor) ; Šušor, Andrej (referee) ; Procházka, Radek (referee)
The PhD thesis is focused on the effect of porcine sperm cell extracellular ubiquitination on early embryonic development up to the blastocyst stage after ICSI. In addition, it also presents a potential improvement of the technique of in vitro fertilization using oocyte incubation with ion channels regulators. To address these aims, we established an entirely novel methodology for sperm cell sorting using flow cytometry and subsequent cryopreservation. We determined the conditions for successful sperm cell sorting based on extracellular ubiquitination rate providing highly specific selection as well as sufficient numbers of viable sperms for fertilization using the ICSI method. Concerning the following cryopreservation, established methods were optimized to enable freezing of a minimal sperm cell suspension volume with low cell numbers. The performed experiments showed a direct relationship between the rate of extracellular ubiquitination and the capability of sperms to give rise to a properly developing embryo. Highly ubiquitinated sperm cells were less successful regarding the embryonic development to the blastocyst stage if compared with the lowly ubiquitinated group (6,2 % vs. 16,7 %, P<0,001). Interestingly, the rate of extracellular ubiquitination showed no effect on the pronuclear formation...
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The Long-term Natural Corrosion of Uranium Coloured Glasses
Procházka, Radek ; Goliáš, Viktor (advisor) ; Zeman, Josef (referee) ; Helebrant, Aleš (referee)
klíčová slova: koroze skla, zvětrávání skla, přírodní alterace skla, přírodní analog, uran, experimentální loužení Historická skla barvená uranem byla vyráběna v řadě českých skláren přibližně mezi lety 1830 a 1945. Obsah uranu v těchto sklech se pohybuje v řádu desetin procenta. Materiál představuje vhodný analog tzv. nukleárních skel sloužících k imobilizaci radioaktivního odpadu. Vzhledem ke složitosti procesů předpokládaných v podzemním úložišti v době kdy se odpadní skla dostanou do kontaktu s vodou má materiál velkou vypovídací hodnotu pro posouzení dlouhodobé stability skla v přírodních podmínkách se zaměřením na chování uranu. V předložené práci jsou studovány změny historických uranem barvených skel vystavených až 150 let působení přírodních roztoků v exogenních podmínkách. Během této doby došlo na povrchu vzorků ke korozi. U draselných skel bylo při povrchu zjištěno preferenční vyloužení alkálií a vznik hydratované difúzní zóny o mocnosti až 0,6 mm. V této korodované části bylo pozorováno srážení novotvořeného kalcitu (CaCO3) patrně v důsledku zvýšeného pH. Oproti původnímu sklu byla ve vyloužené zóně potvrzena stabilní, v některých případech zvýšená koncentrace uranu. Ačkoli došlo k vyloužení až 17,5 % K2O a nahrazení prakticky veškerého draslíku ionty H3O+ z roztoku, uran zůstal ve...
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