Doctoral theses

Doctoral theses 24,319 records found  beginprevious12927 - 12936nextend  jump to record: Search took 0.00 seconds. 
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)
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...
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...
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...
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...
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
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
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...
Phase transformations in modern titanium alloys
Šmilauerová, Jana ; Janeček, Miloš (advisor) ; Kalvoda, Ladislav (referee) ; Strunz, Pavel (referee)
This study deals with phase transformations in metastable β titanium alloys, focusing on the investigation of evolution of nanoparticles of thermodynamically metastable ω phase. For the purpose of this research, single crystals of two metastable β titanium alloys - LCB (Ti-6.8Mo-4.5Fe-1.5Al) and Ti-15Mo (in wt. %) - were grown in an optical floating zone furnace. It was established by differential scanning calorimetry that the phase transformations occurring in the material did not change significantly as a result of the single crystal growth process. Using single crystal X-ray diffraction, the shape and the size of ω particles were determined in a series of aged samples. The lattice parameters of ω particles and the β matrix, as well as the misfit between the two structures were calculated. The β phase was found to be locally deformed in compression around ω particles. Small-angle X-ray scattering (SAXS) experiments revealed a spatial ordering of ω particles in the β matrix in a disordered cubic array with the basis vectors along 100 β directions. The SAXS data also allowed the evaluation of the mean ω particle sizes and distances and confirmed that the ω particle growth obeys the t1/3 law following from the Lifshitz-Slyozov-Wagner theory. In situ SAXS performed during isothermal ageing at selected...
Adverse reactions after childhood vaccination in the Czech Republic
Kocourková, Aneta ; Dáňová, Jana (advisor) ; Marešová, Vilma (referee) ; Částková, Jitka (referee)
1 ABSTRACT In the Czech Republic a complex study of adverse reactions after vaccination in children has not been presented yet. Even though reporting of serious adverse reactions to the State Institute for Drug Control (SUKL) is mandatory by law, it is seldom performed. Moreover, there is no analysis correlating adverse reactions that occurred at doctors` surgeries with actual reported adverse reactions to SUKL. The main focus of presented work was to analyze and map adverse reactions appearing after vaccinations from the children's vaccination schedule in the Czech Republic. The study was conducted in the form of retrospective-prospective questionnaires concentrating on adverse reactions, their occurrence, character, seriousness, duration and frequency. Furthermore, the questionnaires also focused on socio-demographic data such as gender, age, residency, parents' education, birth weight. Also, the refusal of the compulsory vaccination was assessed. Occurrence of adverse reactions after vaccination in the Czech Republic was analyzed by questionnaires in pediatricians' surgeries (active surveillance). Obtained data were correlated with data available at SUKL (passive surveillance). The study data showed higher number of collected adverse reactions that number of adverse reactions reported to national program...

Doctoral theses : 24,319 records found   beginprevious12927 - 12936nextend  jump to record:
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