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Úloha některých proteinů při zmrazování spermatu rybXIN, MiaoMiao January 2019 (has links)
Sperm damage during cryopreservation is considered a major obstacle to the expansion of sperm storage technology in fish. In-depth knowledge of cryoinjury and cryoprotectants with respect to the quality of fish sperm can enhance future use of cryopreservation. We used antifreeze proteins as cryoprotective agents to improve the quality of frozen/thawed spermatozoa, along with optimization of cryopreservation protocols. Reviews vitrification, a promising cryopreservation technique for fish sperm storage. Vitrification requires rapid cooling/warming, small volume containers, and use of permeable cryoprotectants at high concentrations to solidify both intra- and extra-cellular materials. While high concentration of cryoprotectant show toxicity to cells. The quantity of permeable cryoprotectant can be reduced or eliminated by use of apparatus or techniques that dramatically increase freezing and warming rates by treating a much smaller quantity of sperm. Thus, vitrification may be more suitable for fish producing small quantities of highly concentrated sperm, but not sturgeon producing high quantities of sperm with low concentration. As second aim of the present study, proteomic methods were applied to characterize the protein profiles of sterlet spermatozoa and seminal plasma and assess their effect on spermatozoa function in conventional cryopreservation. The motility variables of cryopreserved sterlet sperm were also investigated. The motility rate of sterlet sperm significantly decreased after cryopreservation, while no difference in mean curvilinear velocity of fresh and cryopreserved sperm was detected. Six proteins were altered in seminal plasma and thirteen in spermatozoa following cryopreservation. Among them, eight proteins were positively identified: a) two (mitochondrial ATP synthase subunit alpha and heat shock protein 70) were from seminal plasma, associated with metabolism and response to stress; b) four (triosephosphate isomerase, mitochondrial ATP synthase subunit ?, glycerol-3-phosphate dehydrogenase [NAD(+)], enolase B) in spermatozoa are involved in metabolic pathways such as gluconeogenesis and glycolysis to provide efficient energy for spermatozoon movement; c) the other two (tubulin ? chain and tubulin ? chain, testis-specific) in spermatozoa are major constituents of sperm microtubules, playing important roles in the organization of the microtubule cytoskeleton. These results broaden the understanding of protein-related cryoinjury in sperm, which may help to determine the function of altered proteins and provide new insights into improving sperm cryopreservation. Since cryopreservation is known to cause lethal and sublethal damage to sperm, different concentrations of antifreeze proteins (AFPI or AFPIII) were employed as cryoprotectants. The flow cytometry analysis revealed that supplementation with antifreeze proteins was associated with significantly higher membrane integrity in cryopreserved sterlet sperm, except with the use of 0.1 ?g/ml of AFPI. However, motility rate, curvilinear velocity, straight-line velocity, and fertilization rate of frozen-thawed sperm did not differ from that without addition of antifreeze proteins. It was concluded that addition of antifreeze proteins to cryopreservation medium was the source of the protective effects on sperm plasma membrane integrity.
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Změny antikorozního systému nemrznoucích teplonosných kapalin / Changes anticorrosive system non - freezing heat transfer liquidPexa, Michal January 2008 (has links)
This diploma thesis is focused on proposition of non-freezing heat transfer fluid for solar systems. Fluid will be based on mixture of new available compound propane-1,3-diol with water and modern corrosion inhibitors. Then will be investigate, if this new compound is competetive to common used liquids like ethylene glycol or propylene glycol.
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Fyzikálně-chemické aspekty ekologických teplonosných kapalin / Physicochemical Aspects of Ecological Heat-transfer FluidsSkolil, Jan January 2016 (has links)
This thesis develops composition of heat transfer fluids with antifreeze properties next to traditional one component glycols produced from propene and ethene. Based on assessment of physical properties it considers application of progressive antifreeze compounds of glycerine and propan-1,3-diole and their mixtures with classic glycols, which do not have negative influence on the environment and which are produced in last years from renewable sources. Due to the necessity of selection of certain compromise between their heat transfer properties, price, solubility and other factors physical properties of selected mixtures are determined together with synergy of each compound, including formulas with glycols: ethan 1,2 diol and propan 1,2 diol Another evaluated factor of studied formulations in addition to their heat transfer properties was anticorrosive protection of common corrosion inhibitors mixtures. The result of whole work is the proposal of several most perspective formulations based on mixtures of polyhydric alcohols in terms of their features enabling them heat transfer, reasonable costs, and the restrictions of impact of their use, particularly in heat transfer systems, to human health and the environment. The knowledge of physical properties of water solutions of polyhydric alcohols mixtures also helps to better using of recycled materials from planning recycling plant for glycols.
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Stárnutí teplonosných kapalin v termických solárních systémech a propan-1,3-diol jako nová možnost / Degradation of Heat Transfer Fluids in Thermal Solar Systems and Propane-1,3-diol as a New OptionMikšík, František January 2018 (has links)
Stárnutí teplonosných kapalin na organické bázi je dlouhodobým problémem, který je znám od počátku jejich používání. První část této disertační práce je tak věnována případové studii funkčního experimentálního systému, který byl jako nový naplněn teplonosnou kapalinou na bázi propan-1,2-diol a pozorován po období 7 let. Pro analýzu stárnutí kapaliny v tomto systému byly sledovány základní provozní vlastnosti kapaliny jako jsou hustota, viskozita, teplota tuhnutí, pH a obsah kovů. Skrze tyto vlastnosti tak bylo sledováno stárnutí kapaliny nepřímo. Přímé sledování stárnutí bylo posléze provedeno analýzou degradačních produktů, jako jsou organické kyseliny a změny ve složení směsi pomocí izotachoforézy a hmotnostní spektrometrie. Pro srovnání byly taktéž analyzovány vybrané vzorky z několik dalších systémů plněných identickou kapalinou s prokazatelně pokročilou formou degradace. V druhé části práce jsou představeny základní fyzikálně-chemické vlastnosti směsí propan-1,3-diolu s vodou a jejich analytické hodnocení a matematické modelování pro universální použití jakožto nového základu pro nemrznoucí teplonosné kapaliny. Na základě dostupných informací je pak hodnocena použitelnost této směsi. Výhoda propan-1,3-diolu je spatřována především ve výrobě z obnovitelných zdrojů a v některých fyzikálních a chemických vlastnostech, které dle dosavadních poznatků předčívají doposud používané glykolové směsi.
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Nemrznoucí teplonosné kapaliny pro solární systémy / Non - freezing heat transfer liquids for solar systemsMikšík, František January 2010 (has links)
This diploma thesis is focused on proposition of non-freezing heat transfer fluid for solar systems. Fluid will be based on mixture of new available compound propane-1,3-diol with water and modern corrosion inhibitors. Then will be investigate, if this new compound is competetive to common used liquids like ethylene glycol or propylene glycol.
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Nemrznoucí teplonosné kapaliny na bázi glycerolu / Non - freezing heat transfer liquids on glycerol platformTrombik, Tomasz January 2011 (has links)
This thesis is focused on proposition of non-freezing heat transfer fluid. Fluid will be based on mixture of propane-1,2,3-triol with water and modern corrosion inhibitors. Then will be investigate, if this new compound is competetive to common used liquids like ethylene glycol or propylene glycol.
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Nemrznoucí teplonosné kapaliny na bázi polyolů / Non - freezing heat transfer liquids on the polyol platformSolný, Tomáš January 2012 (has links)
This diploma thesis is focused on the evaluation of changes in non-freezing heat transfer liquid composed of mixture of polyols and water, used in the real solar thermic system. On the base of the research a new heat transfer liquid is proposed on the platform of 1,3-polyols. The emphasis is put on the non-toxic properties of such system revealing the two chemical candidates for a new heat transfer liquid: 1,3-propanediol and glycerol. These chemicals are mixed together with water using different volume concentrations and properties of such liquids are evaluated.
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Stárnutí nemrznoucí teplonosné kapaliny v solárních systémech / Monitoring ageing non - freezing heat transfer liquidsPidima, Tomáš January 2014 (has links)
This thesis deals with the evaluation of changes in properties of an antifreeze heat transfer fluid based on polyols used in real solar thermal system. Emphasis is placed on the use of substances with low impact on the environment.
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Návrh systému měření teplot na zkušebně tepelných čerpadel / Concept of Temperature Measurement System on Heat Pump Test-roomMacháčková, Petra January 2011 (has links)
This work deals with design of temperature measurement on heat pump test-room. Discusses diferent various variants of thermometers and their placements in measurement circuit. It contains sample software for control and processing of measured data on the test-room, which is controlled by the computer and built-in data acquisition card.
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Sledování stárnutí nemrznoucí teplonosné kapaliny nové generace / Monitoring ageing non - freezing heat transfer liquids new generationFousek, Pavel January 2017 (has links)
This diploma thesis deals with the evaluation of changes in properties of an antifreeze heat transfer liquids based on glycols used in real solar thermal system. Emphasis is placed on the use of non-toxic substances, which include propane-1,3-diol.
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