Desorption Electrospray Ionization Mass spectrometry Imaging (DESI-MSI) is an area of great interest and a promising tool in the field of chemical imaging. It is a powerful, label-free technique, which can determine, map and visualize different molecular compounds on a sample surface. The amount of information acquired in a single DESI-MSI experiment is enormous compared to other techniques, as it can simultaneously detect different compounds with their spatial distribution on the surface. The experiment can be used to produce two-dimensional and three-dimensional images. Chapter 2 focuses on the design and optimization of the setup for performing DESI-MS imaging on various substrates. The proposed setup was tested for its lateral spatial resolution. To provide proof-of-concept of the design, preliminary tests were performed to generate images from commercial thin layer chromatographic plates and photographic paper. Chapter 3 focuses on demonstrating the compatibility of novel microfabricated Thin Layer Chromatography plates (M-TLC plates) for detection with DESI-MSI.

Keywords: ambient ionization techniques; mass spectrometry; desorption electrospray ionization; desorption atmospheric pressure photoionization; thin layer chromatography; lipids, mass spectrometry imaging Ambient ionization technique in mass spectrometry is an ionization, which carries out in open space outside the machine and which does not require any, or only a minimal sample pretreatment. DESI (desorption electrospray ionization) and DAPPI (desorption atmospheric pressure photoionization) equipped with software control of the spray emitter position for analysis of low molecular organic compounds were investigated in this thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate. Conditions for the successful analysis of phospholipids, wax esters and some other compounds were developed. Ambient ionization techniques were quantitatively compared. The application was HPTLC/DESI-MS of lipid's mixture and HPTLC/DAPPI-MS of vernix caseosa. DAPPI-MS was applied for the analysis of termites of Prorhinotermes genus (Isoptera, Rhinotermitidae). Pilot experiments of two dimensional analysis and mass spectrometry imaging were realized.

Ambient ionization techniques, such as nanoDESI and nanoESI, allow for the direct analysis of complex samples under atmospheric pressure with no sample pretreatment. These ionization techniques are utilized for a variety of applications, including lipidomics, online reactions and imaging of small molecules. Nanoelectrospray ionization (nanoESI) is an ionization technique that is similar to electrospray ionization (ESI) but uses smaller sample volumes. NanoESI can be used for complex biological sample analysis and when coupled with online photochemical reactions, such as the Paternò-Büchi (PB) reaction, structural information about lipids can be determined. Likewise, nanoDESI is another ambient ionization technique that employs the ESI mechanism but incorporates online liquid extraction of analytes. This technique is easily incorporated to mass spectrometry imaging (MSI) to provide spatial localization of biomolecules in tissues. Additionally, nanoDESI allows for tunable solvent extraction and online derivatization reactions. These techniques were used to determine structural information of neutral lipids, to image lipids from different developmental stages of lung tissue, and to image and quantify small molecule drugs and metabolites in tissue.

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South Asian Americans are one of the fastest growing sub-groups within the Asian American population in the United States today. Between 1960 and 1990, the South Asian American population witnessed an increase of approximately 900% (Leonard, 1997). This increase in population also corresponds with the increase in South Asian American students enrolling in institutions of higher education. However, despite their physical visibility on college and university campuses across the nation, South Asian American students remain invisible in higher education research. Student affairs practitioners have a limited understanding of the unique needs and issues confronted by South Asian American college students. This qualitative study addressed the paucity of research on South Asian American college students by specifically exploring the college experiences of South Asian American women. In particular, the study examined the central intergenerational issues between first-generation South Asian mothers who immigrated to the United States as adults and second-generation South Asian American daughters who are currently enrolled at the University of Texas at Austin. Secondly, it investigated the impact of these intergenerational issues on the identity development and overall college experiences of second-generation South Asian American female college students. Using a postcolonial, critical feminist framework, this study attempted to dismantle the one-dimensional, dominant narrative of South Asian Americans as the successful, high-achieving, model minority and present instead the multi-layered and complex narratives of these participants. Key findings indicated that the intergenerational issues between mothers and daughters were complex with both negative and positive impacts on the mother-daughter relationships, identity development, and the overall college experiences of the daughters. The transmission of culture and cultural values were primary ways in which mothers affected the identity development of their daughters. South Asian American peers and social networks were another significant source of identity development for the students. Additionally, narratives of both mothers and daughters revealed that the impact of the model minority image on women was qualitatively different than men where women had to often strive to fulfill simultaneous expectations of being a successful student and professional as well as conforming to the standards of being the model traditional South Asian wife and mother. / text

Que ce soit lors de la prévention d'actes malveillants ou l'expertise post-attentat, les techniques de prélèvement par frottis et d'analyse d'explosifs se doivent d'être à la fois fiables et sensibles. La méthode par chromatographie en phase liquide (HPLC) couplée à la spectrométrie de masse (MS) présente les caractéristiques requises mais nécessite une étape importante de préparation de l'échantillon et un temps d'analyse conséquent. L'évaluation des performances du couplage HPLC-MS pour l'analyse de frottis réalisés sur des matrices textiles et le développement d'une méthode d'analyse directe et quasi-instantanée de la surface de l'échantillon constituent l'objet de ce mémoire. Pour ce second objectif, les sources d'ionisation ambiante DESI et DART, couplées à la spectrométrie de masse haute résolution (HRMS) ont été utilisées. Une part importante de ce travail a été consacrée à l'étude des mécanismes CID des explosifs, lors de laquelle la HRMS a montré tout son intérêt. Si l'utilisation de la source DESI est plus délicate pour l'étude des surfaces textiles hydrophiles et absorbantes, le potentiel qualitatif de la source DART a été démontré avec succès sur des échantillons simulés et réels. Des résultats prometteurs illustrent la validité de cette approche analytique à la fois sensible, rapide et facile à mettre en ¿uvre, et encouragent à poursuivre les travaux vers une analyse quantitative. / Swabbing and analysis protocols for trace explosives detection have to be both reliable and sensitive, either for prevention measures against bomb attacks or for post-blast scene investigations. The coupling of mass spectrometry (MS) with liquid chromatography (HPLC) offers the required features but important sample preparation steps are often needed and chromatographic separations can require long run times. The evaluation of an LC-MS coupling for the analysis of fabric swabs and the development of a direct and nearly instantaneous method for sample surface analysis are the subjects of this dissertation. DESI and DART ion sources coupled with high resolution mass spectrometry (HRMS) were used for this second method. Part of this work was devoted to the study of CID mechanisms of explosives, in which HRMS appears to present a great interest. Even though the use of DESI source for hydrophilic and absorbent fabric samples analysis is tricky, DART source was successfully applied to qualitative analysis of simulated as well as real samples. Very promising results strengthen the relevance of this direct approach both sensitive, rapid and easily implementable, and encourage pursuing the studies toward quantitative analysis. Keywords: Forensic, explosives, fabrics, extraction, high resolution mass spectrometry, ESI, ambient ionization/desorption (DESI, DART), CID mechanisms, negative ions.

Mass spectrometry imaging (MSI) has been extensively used to produce qualitative maps of distributions of proteins, peptides, lipids, neurotransmitters, small molecule pharmaceuticals and their metabolites directly in biological tissue sections. Moreover, during the last 10 years, there has been growing demand to quantify target compounds in tissue sections of various organs. This thesis focuses on development and application of a novel instrument- and manufacturer-independent MSI software suite, msIQuant, in the open access format imzML, which has been developed specifically for quantitative analysis of MSI data. The functionality of msIQuant facilitates automatic generation of calibration curves from series of standards that can be used to determine concentrations of specific analytes. In addition, it provides many tools for image visualization, including modules enabling multiple interpolation, low intensity transparency display, and image fusion and sharpening. Moreover, algorithms and advanced data management modules in msIQuant facilitate management of the large datasets generated following rapid recent increases in the mass and spatial resolutions of MSI instruments, by using spectra transposition and data entropy reduction (at four selectable levels: coarse, medium, fine or superfine) before lossless compression of the data. As described in the thesis, implementation of msIQuant has been exemplified in both quantitative (relative or absolute) and qualitative analyses of distributions of neurotransmitters, endogenous substances and pharmaceutical drugs in brain tissue sections. Our laboratory have developed a molecular-specific approach for the simultaneous imaging and quantitation of multiple neurotransmitters, precursors, and metabolites, such as tyrosine, tryptamine, tyramine, phenethylamine, dopamine, 3-methoxytyramine, serotonin, gamma-aminobutyric acid (GABA), and acetylcholine, in histological tissue sections at high spatial resolution by matrix-assisted laser desorption ionization (MALDI) and desorption electrospray ionization (DESI) MSI. Chemical derivatization by charge-tagging primary amines of analytes significantly increased the sensitivity, enabling mapping of neurotransmitters that were not previously detectable by MSI. The two MSI approaches have been used to directly measure changes in neurotransmitter levels in specific brain structures in animal disease models, which facilitates understanding of biochemical mechanisms of drug treatments. In summary, msIQuant software has proven potency (particularly in combination with the reported derivatization technique) for both qualitative and quantitative analyses. Further developments will enable its implementation in multiple operating system platforms and use for statistical analysis.

This diploma thesis is a monograph of the architect Otto Rothmayer. The analysis focuses on the symbiotic cooperation with his fellow architect Josip Plečnik at the Prague Castle, but also studies Rothmayer's other projects. Besides villas that Rothmayer designed for his friends, artistic blacksmith Otakar Hátle and sculptress Hana Wichterlová, the analysis will focus on the recently restored family villa of Božena and Otto Rothmayer in Střešovice, Prague. In addition to Rothmayer's architectural work, this thesis also studies Rothmayer's lifelong activity as a designer. By reflecting on this architect's various professional accomplishments, this thesis attempts to refine Otto Rothmayer's place in 20th century Czech architecture.