The main aim of this thesis is to design a communication and control card for an electron microscope, eventually for other equipments of the company Delong Instruments a.s., which is dealing with its development and production. This card should replace existing communication card because of its low computational performance. Also, it should replace control and measure card manned with A/D and D/A converters. Thus, the new card will be providing not only the communication with a superior PC and other electronic systems, but also the control of other subsystems of the electron microscope, the determining of processional states and the measuring of internal physical quantities. At the beginning the requirements were determined and the main concept was made with the inclusion of the simple block diagram. It was very important to choose a suitable microcontroller, which will be an intelligence of the whole card and so it will be the most important component. The accent was set mainly on the sufficient computational performance, high modularity of its periphery, good vision of the future innovation and support and, of course, the price. The next requirement was the implementation of the Ethernet, which will be used for the communication between the card and the superior PC. The microcontroller which was chosen have the core architecture ARM Cortex-M3 and it is described in separate chapter. The next part of this thesis is dealing with the main communication standard of the card, which is the Ethernet. After the general description, the Ethernet was mainly discussed in context of the chosen microcontroller. The possibilities of the application of higher layer TCP/IP protocols were also discussed. Implied part of the thesis was the selection of other important components, especially A/D and D/A converters. Its characteristics will have a big effect on the characteristics of the card. In the last and the most important phase the electrical scheme was designed and it was described in detail. This scheme is the main result of this thesis and it is the main document for the future realization. Designed card will be able to process and control 16 differential analogue input signals, 16 differential analogue output signals, 8 digital inputs, 8 simple digital outputs and 4 digital outputs triggered by optocouplers. It will be able to communicate with the superior PC over the Ethernet with the maximum bit rate of 100 Mbit/s, with other electronic cards over the serial line UART through the optical fibers and with other internal and external equipments over the RS-485 and RS-232.

Tato práce se zabývá návrhem a implementací zařízení na měření opakovatelnosti pohybu goniového mechanismu, dále měřením pohybových vlastností mechanismu a vyhodnocením naměřených dat. Popisuje navrhnuté a zavedené změny na mechanismu a vyhodnocuje vlastnosti prototypu.

This diploma thesis deals with the structural analysis of semiconductor nanowires by transmission electron microscopy. The construction of microscope is introduced together with its basic imaging modes and with the function of each construction element in these modes. In the experimental part the results of analysis of several germnaium nanowires are discussed, with emphasis on their crystallographic structure and orientation.

Objective: This study was conducted to determine the effectiveness of physical and mechanical disinfection of P. gingivalis from implant disks and to evaluate bone cells growth and attachment to the disks. Background. Each year, over three million of Americans replacing missing teeth with dental implants. An inflammatory process around an implant that causes bone loss, characterizes peri-implantitis, first diagnosed in the 1980s. The prevalence is approximately 22%. To date, no treatment protocol of peri-implantitis has been proposed. Methods. 207 implants disks. Four different implant surfaces utilized. Disks were contaminated by p. gingivalis and consequentially disinfected by physical means (spraying prophy jet, titanium brush, and ultrasonic activation) and chemically by Hydrogen Peroxide 3%, 0.12% Chlorhexidine Gluconate, and Sodium Bicarbonate. Osteoblasts were added to the disks. Growth factors (Emdogain and Gem21S) were used in two groups. Osteoblast vitality, attachment and morphology were evaluated. Results. On 3iT3 the all disinfection methods had similar results. On Osseotite and Nanotite surfaces, the citric acid combined with ultrasonic activation granted the worse results. Hence, disks that did not have the surface altered by physical decontamination had most cells attached. Hydrogen Peroxide 3% showed to be the most biocompatible and 0.12% Chlorhexidine gluconate showed most cellular toxicity. Implant coating did not influence osteoblast attachment. Growth factors did not promote osteoblast attachment. Conclusion: Further investigations are necessary.

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Masters of Science / The infants of women who smoke during pregnancy have a lower birth mass than those born of women who abstain. Animal studies reveal that reduced growth due to maternal nicotine exposure during gestation is accompanied by lung hypoplasia. Biochemical analysis suggests that these lungs contain more cells which implies that lung damage occurs. In this study we examined the in vivo effects of maternal nicotine exposure (lmg/Kg/day), the equivalent of 32 cigarettes per day, on the following parameters of fetal and neonatal Wistar rat lung:(i) the content and distribution of glycogen in fetal and neonatal lung (ii) the status of connective tissue in neonatal lung (iii) the cell composition of the alveoli in neonatal lung. Fetal rat lungs of ages 17, 18, 19 and 20 days and neonatal lungs of 1, 7, 14 and 21 day old pups were used. Light microscope techniques and special stains were used to investigate glycogen, connective tissue, macrophage numbers and morphological status of the lungs. Fetal rat lungs of ages 17, 18, 19 and 20 days and neonatal lungs of 1, 7, 14 and 21 day old pups were used. Light microscope techniques and special stains were used to investigate glycogen, connective tissue, macrophage numbers and morphological status of the lungs. Transmission electron microscope (TEM) techniques were employed to investigate the characteristics and composition of the alveolus The results show clearly that maternal nicotine exposure elevates pulmonary alveolar macrophage numbers'(PAM's) and lung glycogen levels. The quantity of elastic fibres in 1 day old neonates was significantly reduced but no changes in the quantity of reticulin and collagen fibres was observed. As a result of this change in connective tissue status, emphysema-like lesions and alveolar collapse was evident in the lungs of nicotine-exposed pups. TEM investigations revealed that changes to the composition of alveoli occurred. These included increased numbers of type II pneumocytes with high numbers of lamellar bodies with degenerative changes. Thickening of the blood-air barrier was also observed. The effect of maternal nicotine exposure has been documented in this study. However, it has not been possible to pinpoint the mechanisms involved but explanations have been proposed. Further research is required to elucidate the mechanisms by which nicotine produces these effects. Information thus obtained could help prevent the harmful effects to the fetus and neonate caused by smoking during pregnancy.

The inclusions have a different chemical composition and give the steel different mechanical properties. These inclusions affect several properties of steel. In order to understand how the inclusions will affect the steel properties, the electrolytic extraction of 3D investigate method is applied on the steel grade of 42CrMo4. Then follow with Scanning Electron Microscope (SEM) observation. Steel samples from both ingot and rolling with and without heat treatment are observed and compared with different ratios. The result shown that, heat treatment can be applied for removing carbides successfully. And most inclusions are belonging to Type RS which is rod like MnS. The percentage of broken particles can be up to 80%, which means that the reason for the inclusions broken should be find. And heat treatment can affect the characteristics of elongated MnS.

<p> In this thesis the results of optical and scanning electron microscopic investigations of the evaporation morphology of zinc single crystals are presented. Dislocation etch pits developed on (0001) zinc cleavage surfaces. A mechanism is proposed to account for enhanced evaporation at decorated dislocations. The observation of macroledges on pit faces is reported and attributed to impurity-induced bunching of monatomic ledges, the impurities having out-diffused from the bulk. A proposed model for evaporation of faceted surfaces is used to interpret the ledge morphology which developed when samples were evaporated in an oxygen environment. Finally, a correlation between the effects of bulk impurities and gaseous impurities on ledge morphology is demonstrated.</p> / Thesis / Doctor of Philosophy (PhD)

<p> Dramatic advances over the past decade have occurred in the use of cryogenic electron microscopy (cryoEM) to elucidate the structures of macromolecules at atomic resolution. Unfortunately, the sample preparation process is one of the most time-consuming and empirical methods in the cryoEM workflow. Each sample must be tediously optimized to resolve issues with particle aggregation, ice quality, particle orientation, and particle density to enable high-resolution reconstruction analysis. Post-polymerization modifications of synthetic aqueous bottlebrushes offer a promising approach to streamline the workflow for cryoEM sample preparation. Our approach utilizes synthetic bottlebrush materials comprised of flexible polymer scaffolds bearing grafted side-chains, armed with high affinity ligands at the distal termini of the grafted polymers along the polymer core. Development of water-soluble one-dimensional (1D) synthetic bottlebrush polymers has led to new advancements in the biomaterials, antimicrobial, nanomedicine, and responsive materials fields. These synthetic bottlebrush materials are favorable as they confer properties that linear polymers and small molecules cannot achieve. Moreover, structural manipulations employed during post-polymerization processes can afford bottlebrush polymers with distinguishable topologies for advanced functions. These 1D constructs can be synthesized by atom transfer radical polymerization (ATRP), reversible addition- fragmentation chain-transfer polymerization (RAFT), ring-opening polymerization (ROP), cationic ring-opening polymerization (CROP), anionic ring-opening polymerization (AROP) or ring opening metathesis polymerization (ROMP). The chemical composition of the molecule, number of monomer repeats, grafting density and topology influence the morphology and function of polymer brushes. Elongated, vesicular or micellar morphologies can be specifically tuned for the desired application of the material. The morphology of the polymers can also be manipulated by concentration effects. The morphologies of amphiphilic bottlebrush materials specifically, can typically be influenced by structural topology, solvent choice, or external conditions. ROMP is a living polymerization mechanism that can suffer from catalytic backbiting, causing a loss of livingness. The synthesis of aqueous bottlebrush polymers and the comparison of morphologies via AUC, DLS, AFM and TEM will be presented in this dissertation. The synthetic amphiphilic bottlebrush polymer family presented suffered a loss of livingness and ultimately displayed distinct morphologies, relative to chemical composition, solvent, and ultimately polymerization time. Post-polymerization 11 modifications such as backbone hydrolysis and single-walled carbon nanotube complexation promoted even more unique morphologies of bottlebrushes. These synthetic materials indicate use as promising reagents for cryoEM sample preparation.  </p>

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