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UV-photochemical generation of volatile selenium compounds for ultratrace analysis by AAS
Rybínová, Marcela ; Rychlovský, Petr (advisor) ; Komárek, Josef (referee) ; Šíma, Jan (referee)
This thesis deals with the study of UV-photochemical generation of volatile compounds (UV-PVG) in connection with atomic absorption spectrometry (AAS). Selenium (Se(IV)) was selected as a model analyte and many experiments were carried out to expand the current sum of knowledge of the topic. The study was commenced by assembling the UV-PVG apparatus in the continuous flow mode. The detection method used was AAS with externally heated quartz furnace atomizer. The focus of the first step of the study was on the construction of the volatile compounds generator (UV-photoreactor) with emphasis on the material used; tubes made of teflon or quartz of different diameters were tested. The construction of the apparatus was followed by optimization of the reaction conditions (the type and concentration of the photochemical agent and other agents, which increase the analytical signal; the carrier gas and the auxiliary hydrogen gas flow rate; the sample flow rate). Eventually, the analytical figures of merit of the selenium determination using the proposed method were found. The results showed that teflon reaction tubes are a good competitor to those made of quartz. The accuracy of the method has been successfully verified by analysis of certified reference material and its applicability has been further tested...
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Liver regeneration after partial hepatectomy in rats suffering from non-alcoholic fatty liver disease
Garnol, Tomáš ; Červinková, Zuzana (advisor) ; Pantoflíček, Tomáš (referee) ; Šiller, Jiří (referee)
1. SUMMARY Liver regeneration after partial hepatectomy in rats suffering from non-alcoholic fatty liver disease Non-alcoholic fatty liver disease (NAFLD) is currently the most frequent chronic liver disease in economically developed countries with prevalence of about 30 %. Liver resection from different reasons is nowadays common surgical procedure. Successful recovery and renewal of liver functions depend on regenerative capacity of liver remnant. The course of liver regeneration could be profoundly influenced by concomitant liver pathological processes including NAFLD. The aim of this work has been study of early phase of liver regeneration after partial hepatectomy (PHx) in rats with nutritionally induced simple steatosis. At the beginning we introduced a model of NAFLD by a high-fat diet giving to Wistar or Sprague-Dawley rats for 3 and 6 weeks, resp. This regimen induced simple steatosis without signs of inflammation, necrosis or fibrotic changes in both strains. In the second part of our study we followed if liver regeneration after PHx in rats with NAFLD is altered. Liver regeneration was assessed by bromodeoxyuridin incorporation into DNA of hepatocytes. Regeneration of liver with simple steatosis induced by 2/3 PHx was not significantly influenced in comparison to non-steatotic liver. The only...
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Possibilities of clinical use single and tandem shock waves.
Zeman, Jan ; Beneš, Jiří (advisor) ; Kneppo, Peter (referee) ; Bolek, Lukáš (referee)
Shock waves have been used in medicine for more than 30 year. At the beginning was mainly use for lithotripsy, but today is also applied in other fields of medicine, such as orthopedics, rheumatology and others. Single shock wave is one shock that usually is repeated every 1-1.5 seconds. By contrast tandem shock waves are two shocks consecutively (ideal interval between shocks is from 8 to 15 microseconds), that are repeated. In this work we investigated the clinical use of single and tandem shock waves that are generated entirely new source. It is based on the principle of multichannel discharge. It was found that a single shock wave can destroy the union between bone and bone cement, this effect could be used in orthopedics. Single and tandem shock wave can damage the tumor in vivo, but the principle damage is different. Tandem shockwave is able to cause damage in a depth of acoustically homogeneous medium and enhances the effect of chemotherapy. It would therefore be possible to used single and tandem shock waves in oncology either alone, or their combination with other chemicals. Functional sample of clinically usable applicator of shock waves with a new source was made for these applications. Powered by TCPDF (www.tcpdf.org)
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Metaphors of Madness: Silenced Myth-Makers and Disordered Brains.
Müller, Matyáš ; Komárek, Stanislav (advisor) ; Horáček, Ivan (referee) ; Fulka, Josef (referee)
The work has basically three aims: 1st to map the wide range of various approaches in the current debate about madness, 2nd to formulate a specific theory of madness, 3rd to identify general philosophical problems the topic brings about, (a 4th aim is also outlined: to understand the presented theory in terms of therapeutic potential). The central thesis of this work is that insanity is an inherently ambiguous and elusive phenomenon and that trying to understand it we are using various metaphors borrowed from other areas, and consequently forget their metaphorical nature. The work is generally motivated by an effort to reconcile conflicting approaches, to understand them as complementary. It also wants to avoid creating an all-embracing synthesis on the one hand, and purely relativistic and pragmatic viewpoint on the other hand. The first part identifies four levels on which particular approaches understand madness as a problem: the level of the individual, the level of the collective, the transpersonal level and the existential level. At the end of the part, I discuss the possibilities and risks of creating a theoretical framework that would enable to understand various contradictory approaches on a common basis. In the second part, I develop my own analysis of madness. It is based on a...
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The role of protein kinase C and its targets in cardioprotection
Holzerová, Kristýna ; Hlaváčková, Markéta (advisor) ; Alán, Lukáš (referee) ; Vízek, Martin (referee)
The mortality of cardiovascular diseases remains high and it likely tends to increase in the future. Although many ways how to increase the resistance against myocardial ischemia- reperfusion damage have been described, few of them were transferred into clinical practice. Cardioprotective effect of chronic hypoxia has been described during 60s of the last century. Its detailed mechanism has not been elucidated, but a number of components has been identified. One of these components presents protein kinase C (PKC). The role of PKC was described in detail in the mechanism of ischemic preconditioning, but its involvement in the mechanism of cardioprotection induced by chronic hypoxia remains unclear. One reason is the amount of PKC isoforms, which have often contradictory effects, and the diversity of hypoxic models used. The most frequently mentioned isoforms in connection with cardioprotection are PKCδ and PKCε. The aim of my thesis was to analyze changes in these PKC isoforms at two different cardioprotective models of hypoxia - intermittent hypobaric (IHH) and continuous normobaric hypoxia (CNH). We also examined the target proteins of PKCδ and PKCε after the adaptation to IHH, which could be involved in the mechanism of cardioprotection. These included proteins associated with apoptosis and...
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Body size as an implicit factor: case studies of life-history strategies and behaviour
Šimková, Olga ; Frynta, Daniel (advisor) ; Sedláček, František (referee) ; Rehák, Ivan (referee)
Body size has a potential to influence almost any trait in animal biology. The thesis contains four case studies (I - IV) covering four various situations and four various taxa, mainly squamate reptiles (Lepidosauria). Body size is a connecting factor for all these studies, in which I and my co-authors tried to elucidate various implications of body size. I. The sex ratio in Cuban boa (Chilabothrus angulifer) litters is often male or female biased. The neonates are so large, that are able to accept the same type of prey as are adults (in contrast to the other Chilabothrus species). We found that both the sexes are of the same size and shape at birth. Large size of the neonates a long lifespan lead to considerable generation overlaps. This could clarify our findings that small females produce sons whereas the larger ones deliver daughters. Males are smaller than females, probably also less philopatric and refuse food during breeding season. We can conclude that females manipulate the sex ratio of neonates according to its own body size, in order to decrease the probability of competition with their own offspring. II. Mangrove-dwelling monitor lizard (Varanus indicus) shows one of the greatest degrees of sexual size dimorphism among monitor lizards. We recorded the growth of the individuals from...
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The Birth of Cyber as a National Security Agenda
Schmidt, Nikola ; Hynek, Nikola (advisor) ; Stevens, Timothy Charles (referee) ; Polčák, Radim (referee)
The following dissertation studies the question how cyber security has become a national security agenda and discusses implications of the observed processes to current international security status quo. I divided the research into three parts. The first part embodies theoretical and methodological approach. The second part studies three distinct discourses related to cyber security, the techno-geek discourse, the crime-espionage discourse and the nation-defense discourse using the method of Michel Foucault about archaeology of knowledge. The third part then draws on these three discourses and discusses implications through lens of several theoretical perspectives. Namely through concepts taken from science and technology studies, from actor network theory and network assemblages. The critical point of the research is a distinct reading of these discourses. While techno-geeks are understood as a source of semiosis, hackers' capability and crypto-anarchy ideology influenced by cyberpunk subculture, the cyber-crime and espionage discourse is read as a source of evidence of the hackers' capability. The inspiration in popular subculture is combined with current efforts in development of liberating technologies against oppression by authorities, oppression recognized by the eyes of the crypto-anarchist...
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Physical and mechanical properties of lead-free solder joints
Harcuba, Petr ; Janeček, Miloš (advisor) ; Drozd, Zdeněk (referee) ; Očenášek, Vladivoj (referee)
Title: Physical and mechanical properties of lead-free solder joints Author: Petr Harcuba Department: Department of Physics of Materials Supervisor: prof. RNDr. Miloš Janeček, CSc., Department of Physics of Materials Abstract: Due to recent restriction of the classical Sn-Pb solder alloy, lead-free solders became an extensively investigated class of materials. This thesis focused on selected Sn-Cu based alloys. The influence of Cu content and minor additions of Ni and P on IMC layers morphology and reliability of simulated solder joints were investigated. The growth kinetics of IMC layers and mechanical properties of solder joints were studied after reaction of molten solders with Cu substrate at various times and temperatures, and after subsequent ageing at elevated temperatures. Detailed analysis of the evolution of IMC layers morphology was performed using EBSD. Higher Cu concentration in solders decreased the dissolution rate of Cu substrate. It was shown that the addition of 0.1 at.% of Ni significantly changed the morphology of IMC layers and improved mechanical properties of solder joints. Addition of P had only a minor effect on the IMC growth and the solder joint reliability. Keywords: Lead-free solders, intermetallic compound layers, growth kinetics, reliability of solder joints
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Preparation and Characterization of Porous Cerium Oxide/Carbon Bilayers on Silion Substrates
Dubau, Martin ; Matolínová, Iva (advisor) ; Jiříček, Petr (referee) ; Píš, Igor (referee)
This doctoral thesis concerns the preparation of porous cerium oxide/carbon bilayers on silicon substrates. In this regard, carbonaceous films in the form of amorphous carbon (a-C) and nitrogenated amorphous carbon (CNx) are considered. The influence of various process parameters of the cerium oxide deposition on the morphology of the final cerium oxide/carbon bilayer is investigated. A correlation could be found between the morphol- ogy of the bilayer and the stoichiometry of the cerium oxide film determined by means of XPS. Furthermore, a study regarding the chemical composition of the used carbonaceous films by means of various spectroscopic techniques is presented. It was found that the chemical composition of the carbonaceous films strongly depends on the deposition con- ditions of these films and influences the behaviour of these films during oxygen plasma treatment and cerium oxide deposition, respectively. 1
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Functionalized microporous polymer networks prepared from ethynylarenes
Stahlová, Sabina ; Sedláček, Jan (advisor) ; Etrych, Tomáš (referee) ; Červený, Libor (referee)
The preparation of a new group of functionalized conjugated polymer networks has been described based on spontaneous quaternization polymerization of ethynylpyridines with bis(bromomethyl)arenes. The networks consisted of polyacetylene chains with pyridyl and pyridiniumyl pendants cross-linked with -CH2(arylene)CH2- links. The variation of the ratio of monomer and quaternization agent in the feed modified the ratio of pyridyl and pyridiniumyl groups in the networks (pyridyl/pyridiniumyl ratios from 0 to 1.32). The networks did not exhibit a permanent microporosity that could be confirmed by nitrogen adsorption at 77 K. Nevertheless, all networks were active in capture of CO2 at 293 K (up to 0.73 mmol CO2/g, 750 Torr). It has been hypothesized that CO2 capture reflected formation of a temporary porous texture of the networks through conformational changes of the network segments enabled by the segments mobility at room temperature. The preparation of functionalized conjugated polymer networks with permanent micro/mesoporosity (SBET up to 667 m2 /g) has been described that was based on chain coordination copolymerization of acetylenic monomers. The copolymerization of 1,4-diethynylbenzene or 4,4'-diethynylbiphenyl with mono or diethynylbenzenes bearing NO2 or CH2OH groups has been demonstrated as...
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