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Rheological properties of biodegradable thermosensitive copolymers
Chamradová, Ivana ; Poláček, Petr (referee) ; Vojtová, Lucy (advisor)
Hlavním cílem předložené diplomové práce byla příprava, charakterizace a reologická studie "inteligentních" injektovatelných hydrogelů, které jsou biodegradovatelné, biokompatibilní a s řízenou životností sestávajících se z hydrofilního polyethylenglykolu (PEG) a hydrofobního kopolymeru kyseliny polymléčné a polyglykolové (PLA/PGA). Výsledný termosenzitivní PLGA–PEG–PLGA kopolymer, který geluje při teplotě lidského těla, byl dále funkcionalizován anhydridem kyseliny itakonové získané z obnovitelných zdrojů, přinášející jak reaktivní dvojné vazby tak i funkční –COOH skupiny na konce kopolymeru. Navíc byl PLGA–PEG–PLGA kopolymer modifikován bioaktivním anorganickým hydroxyapatitem pro použití jako injektovatelné kostní adhezivum. Oba modifikované kopolymery jak ITA/PLGA–PEG–PLGA/ITA tak i PLGA–PEG–PLGA/HAp ovlivňují reologické vlastnosti původního PLGA—PEG—PLGA kopolymeru rozhodující o tom, zda by mohly být nové polymerní materiály vhodné jako injektovatelné nosiče léčiv nebo kostní lepidla v lékařských aplikacích. Experimentální část této práce je zaměřena především na charakterizaci viskoelastických vlastností jak nemodifikovaného PLGA—PEG—PLGA kopolymeru tak i s přidáním ITA nebo HAp metodou obrácených testovacích vialek (TTIM) a dynamickou reologickou analýzou. Výhodou TTIM je vizualizace přechodu sol-gel, určení kritické gelační teploty a kritické gelační koncentrace. Reologická měření poskytují informace o viskozitě a vizkoelasticitě gelu změnou elastického (G´) a ztrátového (G´´) modulu. Připravené kopolymery byly také charakterizovány 1H NMR a GPC. Povrch a velikost částic HAp byl popsán pomocí SEM a laserového analyzátoru částic. Původní PLGA—PEG—PLGA kopolymer i kopolymer modifikovaný ITA a HAp vykazovaly sol-gel přechod vyvolaný zvýšením teploty. Reologické vlastnosti kopolymerů v koncentračním rozmezí 6 až 24 hm. % ve vodě byly studovány buď TTIM nebo užitím reometru a získané výsledky spolu velmi dobře korespondovaly. Reologické vyhodnocení prokázalo dvě „překřížení“, kde G´ =G´´. První překřížení velmi dobře korespondovalo s prvním sol-gel přechodem nalezeným prostřednictvím TTIM. Maximální hodnota G´ odpovídající nejvyšší tuhosti polymerního gelu byla situována v bílém gelu. Druhý fázový přechod představuje přechod mezi gelem a suspenzí, kdy je bílý polymer oddělen od vody. Tuhost gelu roste s rostoucí koncentrací polymeru ve vodě. Pro srovnání, kopolymer modifikován jak ITA, tak i přidáním HAp (0, 10, 20, 30, 40, 50 hm %) vykázal zvýšení tuhosti gelu oproti původnímu kopolymeru PLGA–PEG–PLGA a přiblížení teploty maximální hodnoty G´ tělesné teplotě (37 °C). Bylo prokázáno, že jak ITA/PLGA–PEG–PLGA/ITA kopolymer tak i PLGA—PEG—PLGA/HAp kompozit jsou vhodnými kandidáty na injekovatelné systémy pro řízené uvolňování léčiv či kostní adhezivum pro ortopedii nebo zubní aplikace.
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Non-conventional bacterial signaling pathways
Krupička, Jiří ; Branny, Pavel (advisor) ; Beranová, Jana (referee)
Two component systems were traditionally considered as main phosphorylation systems of bacteria involved in cell signalling. Recently, attention focuses increasingly on bacterial eukaryote-like Ser/Thr protein kinases (eSTKs). These protein kinases are structurally similar to their eukaryotic counterparts. Some eSTKs possess additional domains such as extracellular PASTA domains that were discovered in a variety of gram-positive bacteria. It has been proved that these domains can act as sensors for unlinked peptidoglycan fragments. However, majority of environmental signal molecules still remains unknown. eSTKs phosphorylate a broad spectrum of substrates including proteins involved in various cell processes such as virulence, cell wall biosynthesis, cell division, and central and secondary metabolism. Cross talk between eSTKs and two component systems also occurs. In this thesis, the current knowledge about eSTKs and their significant substrates in different bacterial species is discussed.
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Engineering optimization models
Tydlačka, Martin ; Plšek, Jan (referee) ; Popela, Pavel (advisor)
A cross-section of a girder made out of profile I is designed with respect to random loads, to which a girder will face during life time. Because the random loads are there, we need another aaproach to solving this exercise. Acceptable aproach is usage of optimisation and four choosen models, solving random loads. The cross-section has been to optimize with respect to minimal weight subject the safety constraint. Goal of this thesis is to present method of transfer structural exercise to exercise of mathematical optimisation, present four choosen models and apply this to exercise with random loads.
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Simple route of caspase-3 FRET sensor synthesis using “click chemistry”
Lišková, Marcela ; Křenková, Jana ; Klepárník, Karel ; Pazdera, P. ; Foret, František
Programmed cell death or apoptosis is regulated process of cell suicide. The central role in apoptosis play cysteine proteases called caspases. Caspases recognize tetra-peptide sequences Asp-Glu-Val-Asp (DEVD) on their substrates and hydrolyze peptide bonds after aspartic acid residues. Various techniques for the determination of caspase-3 are commercially available e.g. Enzyme Linked Immuno-Sorbent Assay (ELISA), Western blotting or flow cytometric analysis. The products of the cleavage can be detected by spectrophotometry, fluorimetry, chemiluminescence (CL) or ELISA. In this work, we suggested fluorescent sensor based on easily prepared Förster Resonance Energy Transfer (FRET). We use very simple chemistry called “click”. This type of chemistry takes advantages of quickness, simplicity and cheapness. “Click chemistry” is based on usage of various functional group and cross-linkers to combine individual molecules together.
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Pharmaceutical market economics: Do public subsidies on pharmaceuticals cause their wasteful use
Petrmann, Milan ; Špecián, Petr (advisor) ; Koubek, Ivo (referee)
This diploma thesis deals with the question of whether do public subsidies cause wasteful use of pharmaceuticals, and if so then to what extent. The hypothesis is tested on the Czech republic data for the years 2005-2012. The biggest contributions are defining the health system as an intra-temporal problem, which tells us that lower values of discount rate implies higher level of wasteful use. I express the environmental issues, which are caused by unprofessional pharmaceutical disposal. You can find the price (-0,11), the income (-0,2) and the cross-price (-0,14) elasticity of demand for pharmaceuticals in the empirical part. These estimates are obtained with the help of the Kuhn-Tucker method. Using the 2OLS method Model 2 comes with the major findings. With 10% increase of public subsidies, consumers tend to waste 13,2% more pharmaceuticals.
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Thermally stratified atmospheric flow modelling
Jirk, Aleš ; Brechler, Josef (advisor) ; Jaňour, Zbyněk (referee)
In this thesis there is simulated an incompressible laminar flow in a higher-order accuracy around a circle cylinder with usage of an immersed boundary method and around a cylinder with a square cross-section with an influence of a thermal stratification. In the theoretical part the system of Navier-Stokes equations with Bussinesq approximation is derived and the methods for simulating are described. Fifth order WENO shock-capturing scheme reconstructs advections terms on the boundaries of control volumes. An explicit fourth-order Runge-Kutta scheme solves the first step of a fractional steps method. The obstacle with the circle cross-section is described by the immersed boundary method. In the implementation section there is interpreted the structure of programs for 2D cases. In the section Numerical experiments there is realized testing of the examples with the exactknown results the linear hyperbolic equations, the Burgers equations and the Euler equations and of a square cavity flow with Reynolds numbers of 100,1000 and 5000 with known numerical results for the Navier-Stokes equation. There is solved the flow around a square (and a circle) cylinder for Reynolds numbers 30; 200. Strouhal numbers are computed for von Kármán vortex street. Finally the flow around a square cylinder with influence of thermal...
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The PXA270M ARM module and its usage as private branch exchange
Vojtíšek, Jindřich ; Šilhavý, Pavel (referee) ; Daněček, Vít (advisor)
This work deals with using the operating system Linux on diskless devices. This is solved on the development kit Voipac PXA270M, which is based on the ARM processor. This work deals further with the distributions of the Linux operating system, which are suitable to use for the device based on the ARM processor. The Linux was chosen because it is one of the most flexible operating systems and the Linux is kept as open source software code, except to the distribution of the Red hat and a few special distributions. The NFS protocol and TFTP are described there. The TFTP and NFS are used to deploy the operating system. It describes there, what are the TFTP and NFS and the principle of their use in computer networks. Practical part is as to, what is needed for the functioning of the TFTP and NFS server on the Ubuntu 11.10 plus how configure them. The OpenOCD is another part of this work. The OpenOCD is designed to work in the device memory. There is shown how to install and run the OpenOCD in order to communicate with the development kit Voipac PXA270M. This work shows how to configure the bootloader U-boot for booting the operating system from the network using the NFS and TFTP. There is described how compile and install PBX Asterisk on Voipac PXA270M with use of cross compiler and how cross compile zlib, OpenSSL and ncurses needed to install nad run Asterisk.
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Trust and Environmental Regulations
Hlaváček, Jan ; Geuss, Erik (advisor) ; Macháč, Jan (referee)
This thesis analyzes impact of social trust on environmental regulations stringency. Negative effect is suggested. Thesis documents that, in a cross section of countries, there is no evidence of such an effect. On the other hand, there is evidence of positive impact of GDP per capita and level of education.
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Krajina v pohraničí a její specifika
Dvořáčková, Klára
ABSTRACT Author: Klára Dvořáčková Title of work: The landscape in the borderland and its specifics. The bachelor thesis is focused on the landscape of the borderland in the National Park Podyjí and ongoing international cooperation join venture with the Thayatal National Park. State of the arts is divided into five parts. The landscape of the national park is described in the first section. Especially it is biotic and abiotic nature. The second and the third fundamental components are agriculture and forestry in this area and their effect on the landscape. The fourth and the fifth section describes the water regime of the National Park Podyjí including tourism related to the municipalities of the national park, following by the practical part of the thesis. The practical part contains the analysis of the economy, especially in the National Park Čížov and the cross-border cooperation with Austria -- neighbouring country. The results discribe situation in the crop and animal production in the area of Čížov and the subsequent care of the landscape. An integral part of the results is the international cooperation between the Podyjí National Park and the Thayatal National Park and their collective activities and administrations of parks. The conclusion presents the development of more environmentally friendly farming in the area of Čížov, and the gradual conversion of the whole area of cultivated land into permanent grassland. The natural location of Čížov creates good conditions for the development of tourism and recreation, which will continue to be developed and supported the common activities of both parks.
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