Research suggests that plaque morphology plays a crucial role in determining plaque vulnerability. However the relationship between plaque morphology and rupture is still not clearly understood due to the limited information of plaque morphology. The aim of this study is to improve our understanding of the relationship between plaque morphology and rupture, and to use this to predict the risk of plaque rupture from the morphology at the molecular level. This can enable the identification of culprit lesions in clinical situations for assessing plaque rupture risk. Histological assessments were carried out on 18 carotid plaque specimens. The 3-D collagen, lipid and macrophage distributions along the entire length of the plaque were analysed in both ruptured and non-ruptured symptomatic plaques. In addition, plaque morphology on the rupture sites were examined and compared with the surrounding regions. It was found that ruptured plaques had thinner fibrous caps and larger lipid cores compared to non-ruptured plaques. Also, ruptured plaques had lower collagen content compared to non-ruptured plaques, and higher collagen contents upstream compared to downstream region from the plaque throat. At the rupture site there was lower collagen content, and a larger lipid core thickness behind a thin fibrous cap compared with the mean for the longitudinally adjacent and circumferential regions. Macrophage cells were located nearer to the boundary of the luminal wall in ruptured plaques. For both groups, the area occupied by macrophages is greater at the upstream shoulder of the plaque. There is a positive correlation between macrophage area and lipid core area, a negative correlation between macrophage area and collagen content, and between lipid core size and collagen content for both plaque groups. 3D reconstruction of ex-vivo specimens of carotid plaques were carried out by a combined analysis of US imaging and histology. To reconstruct accurate 3D plaque morphology, the non-linear tissue distortion in histological images caused by specimen preparation was corrected by a finite element (FE) based deformable registration procedure. This study shows that it is possible to generate a 3D patient specific plaque model using this method. In addition, the study also quantitatively assesses the tissue distortion caused by histological procedures. It shows that at least 30% tissue shrinkage is expected for plaque tissues. The histology analysis result was also used to evaluate ultrasound (US) tissue characterization accuracy. An ex-vivo 2D ultrasound scan set-up was used to obtain serial transverse images through an atherosclerotic plaque. The different plaque component region obtained from ultrasound images was compared with the associated histology result and photograph of the sections. Plaque tissue characterisation using ex-vivo US can be performed qualitatively, whereas lipid core assessment from ultrasound scan can be semi-quantitative. This finding combined with the negative correlation between lipid core size and collagen content, suggests the ability of US to indirectly quantify plaque collagen content. This study may serve as a platform for future studies on improving ultrasound tissue characterization, and may also potentially be used in risk assessment of plaque rupture.

The topic of the diploma thesis is A Linguistic Analysis of a Baroque Sermon. The text, written by Václav Ignác Blovský, dates back to 1724. The diploma thesis continues in my bachelor work. It´s aim was to give the analysis of phonetic and morphological features of the same text. The diploma thesis is divided into two parts - the theory and the research. The first one deals with the author´s life and his work, the cult of St. John of Nepomuk and sermons dedicated to this Czech patron saint in general. The analytical part summaries the results of the previous research and includes the syntactic analysis. The aim of the diploma thesis is to find out the level of the Czech language in the early 18th century on the basis of the findings.

This diploma thesis continues in my bachelor work. It´s topic was the analysis of three preachments by Daniel Nitsch from the collection called Berla královská Jezu Krista (1709). The purpose of the task was to make an analysis of phonetic appearances in these preachments and to find out the presence of spoken components in author´s language. The topic of my diploma thesis is the morphological analysis of the preachment called Já hlas volajícího na poušti by the same writer. There will be observed especially searched appearances different from the present Czech. This research might continue with the analysis of the composition or stylistics. The work is divided into two parts ? the theory and the research. The first one deals with the life and work of Daniel Nitsch, the brief charakteristics of the baroque period, the definition of the baroque Czech, the progress of humanism and baroque grammars, level of the contemporary language and the orthografical codification of humanism Czech. The research includes the morphological analysis of the text and the statistic formulation of the number of searched appearances. The purpose of the analysis is to find out the level of Czech language at the beginning of the 18th century on the base of the findings and graphic data.

<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>

Vibration compaction is the most effective way of compacting coarse-grained materials. The effects of vibration frequency and amplitude on the compaction density of different backfill materials (No. 4 natural sand, No. 24 stone sand and No. 5, No. 8, No. 43 aggregates), were studied in this research. The test materials were characterized based on the particle sizes and morphology parameters using digital image analysis technique. Small-scale laboratory compaction tests were carried out with variable frequency and amplitude of vibrations using vibratory hammer and vibratory table. The results show an increase in density with the increase in amplitude and frequency of vibration. However, the increase in density with the increase in amplitude of vibration is more pronounced for the coarse aggregates than for the sands. A comparison of the maximum dry densities of different test materials shows that the dry densities obtained after compaction using the vibratory hammer are greater than those obtained after compaction using the vibratory table at the highest amplitude and frequency of vibration available in both equipment. Large-scale vibratory roller compaction tests were performed in the field for No. 30 backfill soil to observe the effect of vibration frequency and number of passes on the compaction density. Accelerometer sensors were attached to the roller drum (Caterpillar, model CS56B) to measure the frequency of vibration for the two different vibration settings available to the roller. For this roller and soil tested, the results show that the higher vibration setting is more effective. Direct shear tests and direct interface shear tests were performed to study the impact of particle characteristics of the coarse-grained backfill materials on interface shear resistance. A unique relationship was found between the normalized surface roughness and the ratio of critical-state interface friction angle between sand-gravel mixture with steel to the internal critical-state friction angle of the sand-gravel mixture.

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Today many cell biological techniques study large cell populations where an average estimate of individual cells’ behavior is observed. On the other hand, single cell analysis is required for studying functional heterogeneities between cells within populations. This thesis presents work that combines the use of microfluidic devices, optical microscopy and automated image analysis to design various cell biological assays with single cell resolution including cell proliferation, clonal expansion, cell migration, cell-cell interaction and cell viability tracking. In fact, automated high throughput single cell techniques enable new studies in cell biology which are not possible with conventional techniques. In order to automatically track dynamic behavior of single cells, we developed a microwell based device as well as a droplet microfluidic platform. These high throughput microfluidic assays allow automated time-lapse imaging of encapsulated single cells in micro droplets or confined cells inside microwells. Algorithms for automatic quantification of cells in individual microwells and micro droplets are developed and used for the analysis of cell viability and clonal expansion. The automatic counting protocols include several image analysis steps, e.g. segmentation, feature extraction and classification. The automatic quantification results were evaluated by comparing with manual counting and revealed a high success rate. In combination these automatic cell counting protocols and our microfluidic platforms can provide statistical information to better understand behavior of cells at the individual level under various conditions or treatments in vitro exemplified by the analysis of function and regulation of immune cells. Thus, together these tools can be used for developing new cellular imaging assays with resolution at the single cell level. To automatically characterize transient migration behavior of natural killer (NK) cells compartmentalized in microwells, we developed a method for single cell tracking. Time-lapse imaging showed that the NK cells often exhibited periods of high motility, interrupted with periods of slow migration or complete arrest. These transient migration arrest periods (TMAPs) often overlapped with periods of conjugations between NK cells and target cells. Such conjugation periods sometimes led to cell-mediated killing of target cells. Analysis of cytotoxic response of NK cells revealed that a small sub-class of NK cells called serial killers was able to kill several target cells. In order to determine a starting time point for cell-cell interaction, a novel technique based on ultrasound was developed to aggregate NK and target cells into the center of the microwells. Therefore, these assays can be used to automatically and rapidly assess functional and migration behavior of cells to detect differences between health and disease or the influence of drugs. The work presented in this thesis gives good examples of how microfluidic devices combined with automated imaging and image analysis can be helpful to address cell biological questions where single cell resolution is necessary. / <p>QC 20130927</p>