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Microelectromechanical systems (MEMS) technology allows the realization of mechanical parts, sensors, actuators and electronics on silicon substrate. An attractive utilization of MEMS is to develop micro instruments for chemical analysis. An example is gas chromatography (GC) which is widely used in food, environmental, pharmaceutical, petroleum/refining, forensic/security, and flavors and fragrances industries. A MEMS-based micro GC (µGC) provides capabilities for quantitative analysis of complex chemical mixtures in the field with very short analysis time and small amounts of consumables. The aim of this research effort is to enhance the sensitivity and selectivity of µGC instruments by implementing chemical amplification method known as preconcentration. A micro preconcentrator (µPC) extracts the target analytes from the sample matrix, concentrates them, and injects them into the separation column for analysis. This work resulted in the development of silicon-glass bonded chips consisting of 7 mm x 7 mm x 0.38 mm multiport cavity with thousands of embedded 3D microstructures (to achieve high surface-to-volume ratio) coated with polymeric thin film adsorbents. Deep reactive ion etching (DRIE) was the enabling technology for the realization of µPCs. Several coating methods, such as inkjet printing of polymers and polymer precipitation from solution have been utilized to coat complex geometrical structures. One major outcome was the development of cobweb adsorbent structure. Moreover, the porous polymeric adsorbent Tenax TA in the film form was characterized, for the first time, for μPC application and shown to have similar properties to that of the granular form. Several μPC designs were experimentally evaluated for their performance in concentrating volatile organic compounds, including cancer biomarkers, Propofol (anesthetic agent), environmental pollutants, and chemical warfare simulants. The possibility of utilizing the μPCs in practical applications such breath analysis was also demonstrated. / Ph. D.

Measuring lipid oxidation is useful as a means of monitoring oxidative stress, such as that induced by clinical conditions or environmental exposure. Characteristic volatile compounds, often with low threshold odors, are secondary products of lipid oxidation reactions. Metallic flavor in food and beverages has been linked with oxidation of lipids in the oral cavity. Breath, an emerging medium for analysis of internal condition, is one means of measuring the metal-induced lipid oxidation responsible for this flavor. This project analyzes the breath of human subjects, as well as lipid oxidation of in vitro samples to identify compounds responsible for producing metallic flavor, which result from the oxidation of lipids in the oral cavity. Because these analytes are found at extremely low (picomolar to nanomolar) concentrations, preconcentration of samples prior to gas chromatography-mass spectrometry analysis is crucial. This study utilizes both solid phase microextraction (SPME) and micromachined silicon micropreconcentrators to concentrate compounds in breath to optimize analysis. / Master of Science

The places in which we live have a direct influence on our health and wellbeing. The interest in human health and experience of a space was apparent in the work of 20th century architects such as Le-Corbusier and Alvar Aalto during the tuberculosis epidemic. The Paimio Sanatorium, which was a collaboration between doctors and architect by Alvar Aalto in 1929-33, was one of the most famous projects that shows the tuberculosis influence on architecture. Therefore, the need to redesign spaces in order to live a happier and healthier life began to influence modern architecture from the early 20th century. The change of body perception because of disease impacted architecture, reconfiguring it in a way that the building could function as a medical tool. However, after years of living in a world without pandemics, designers just about to forget the importance of the design and its influence on human health. Although, the new restrictions placed on society due to Covid-19 outbreak, played an important role to reconsider the functional connection between the built environment and human wellness. This thesis explores the ways that the built environment and its surroundings can affect human physical and mental wellbeing by examining the ways that the world has adapted to the new trends and strategies through the design of an assisted living facility in Oldtown, Alexandria, Virginia. / Master of Architecture / In the early months of 2020, the World Health Organization announced a pandemic due to Covid-19 which was first reported in China. Following the WHO declaration, people were forced to be quarantined for months. The fear of the contagious airborne disease became the most important factor in determining which spaces people can safely frequent. Therefore, space became an essential component of concern during the Covid-19 pandemic and will continue to play a role in architecture thereafter. These issues are examined through the design of an assisted living facility in Oldtown Alexandria, Virginia.

In this work, we performed an experimental analysis using a two-dimensional semiconducting transition metal dichalcogenide (TMD), specifically tungsten diselenide (WSe2), for gas sensor applications. Our method entailed building a chemically liquid exfoliated WSe2 gas sensing device with gold (Au) electrodes to measure its reaction and sensitivity to environmental gasses such as CO2 and N2. The 2D thin film was created through a solution processing method and electrically coupled in a two-terminal configuration; photonic curing system along with the hot plate annealing process was used on the thin film for rapid annealing, enhancing particle connectivity, stable crystal structure, and increasing overall electrical conductivity. The inkjet printing technology is used to explore the potential of the 2D thin film fabrication process that defines a well-controlled and scalable additive manufacturing process at the nano level that makes it possible to develop next-generation flexible devices. The additive nano-manufacturing process allowed us to establish the film's structure and chemical properties before measuring the electrical characteristics of the films when exposed to CO2 and N2 gases at room temperature. To explore and validate the sensitivity to human interaction with the gas-sensing device, we carried out further experiments with direct exposure to human breath in an open environmental space which shows a promising landmark for developing a next-generation flexible breath-sensing device.

Lau Yin Kei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 58-79). / Abstracts in English and Chinese. / Acknowledgement --- p.I / Abstract --- p.IV / Abstract in Chinese --- p.VI / Abbreviations --- p.VIII / Introduction --- p.1 / Chapter 1.1 --- Prevalence of COPD and asthma in Hong Kong --- p.1 / Chapter 1.2 --- Players in pathogenesis of COPD --- p.2 / Chapter 1.3 --- Players in pathogenesis of asthma --- p.4 / Chapter 1.4 --- The use of exhaled breath condensate in previous studies --- p.6 / Chapter 1. 5 --- Brief overview of chemokines --- p.8 / Chapter 1.6 --- Objective of this study --- p.12 / Materials and methods --- p.14 / Chapter 2.1 --- Study population --- p.14 / Chapter 2.1.1 --- Patients with COPD and control subjects --- p.14 / Chapter 2.1.2 --- Patients with asthma and control subjects --- p.15 / Chapter 2.2 --- Lung function --- p.15 / Chapter 2.3 --- Dyspnoea score measurement of patients with COPD --- p.16 / Chapter 2.4 --- Classification of patients and asthma severity --- p.16 / Chapter 2.5 --- Skin prick test and blood tests --- p.16 / Chapter 2.6 --- Collection of exhaled breath condensate --- p.17 / Chapter 2.7 --- Measurement of constituent in EBC --- p.17 / Chapter 2.7.1 --- "Measurement of 8-isoprostane, MCP-1 and GROα in patients with COPD and the corresponding control subjects" --- p.17 / Chapter 2.7.2 --- Measurement of eotaxin and MDC of patients with asthma and the corresponding control subjects --- p.18 / Chapter 2.8 --- Reproducibility of exhaled breath constituent --- p.18 / Chapter 2.8.1 --- "Assessment of reproducibility of the exhaled MCP-1, GROα and8- isoprostane measurements" --- p.19 / Chapter 2.8.2 --- Assessment of reproducibility of the exhaled eotaxin and MDC measurement --- p.19 / Chapter 2.9 --- Statistical analysis --- p.19 / Results --- p.21 / Chapter 3.1 --- Patients with COPD and corresponding control subjects --- p.21 / Chapter 3.2 --- Patients with asthma and corresponding control subjects --- p.28 / Discussion --- p.36 / Chapter 4.1 --- "Exhaled 8-isoprostane, GRO-α and MCP-1 of patients with COPD and corresponding control subjects" --- p.36 / Chapter 4.2 --- Exhaled eotaxin and MDC from patients with asthma and corresponding control subjects --- p.43 / Chapter 4.3 --- Technical aspects of EBC assessment --- p.49 / Future prospect --- p.54 / Conclusion --- p.56 / References --- p.58 / Tables and Figures / Table 1. Demographics of the COPD and control subjects --- p.22 / Figure 1. The level of 8-isoprostane in the exhaled breath condensate of COPD and control subjects --- p.23 / Figure 2. The level of GROa in the exhaled breath condensate of COPD and control subjects --- p.25 / "Figure 3 Bland and Altman's Plot of the repeatability of 8-isoprostane, GROa and MCP-1 in the exhaled breath condensate of normal controls" --- p.27 / Table2. Clinical and physiological details of the subjects --- p.29 / Figure 4. Level of eotaxin in exhaled breath condensate of asthma and control subjects --- p.30 / Figure 5 Level of MDC in exhaled breath condensate of asthma and control subjects --- p.31 / Table 3. Levels of eotaxin and MDC in exhaled breath condensate of asthma subjects on different dose of inhaled corticosteroids --- p.33 / Figure 6. Relationship between exhaled breath condensate level of MDC and total serum IgE level --- p.35

Nous évaluons des films polymères poreux structurés en tant que nouveaux supports pour des photosensibilisateurs de l’oxygène singulet. L’objectif de cette association est l’obtention de matériaux photo-actifs à grande surface d’échange. Ces surfaces polymères, structurées ici en nid d’abeille, sont obtenues par la technique « breath figure » (trad. figure de souffle), à partir de polymères bien définis synthétisés par polymérisation radicalaire contrôlée par des nitroxydes (NMP), par transfert d’atome (ATRP) et par transfert réversible par addition/fragmentation (RAFT). Le photosensibilisateur rose Bengale a été greffé de manière covalente au polymère, soit par post-greffage sur un polymère précurseur, soit par modification d’un monomère fonctionnel puis copolymérisation de ce dernier avec du styrène. Ces différentes synthèses conduisent à des films contenant différents taux de rose Bengale. Les films ont été examinés en microscopie (fluorescence, confocale et champ large, électronique à balayage) afin d’établir la structuration des films et la localisation des espèces fluorescentes. L’efficacité des films polymères pour la photo-oxydation a été testée à l’interface liquide/solide en suivant par spectroscopie UV-visible la dégradation du dihydroxynaphtalène (DHN) ou de l’α-terpinène par l’oxygène singulet produit sous irradiation visible. Les films structurés sont environ cinq fois plus efficaces que les films non-poreux de même composition utilisés dans les mêmes conditions, ce qui s’explique par leur surface spécifique et par la localisation préférentielle du rose Bengale à la surface du matériau. / We evaluate structured porous polymer films as new substrates for photosensitizers of singlet oxygen, with a view to obtaining photo-active materials with high specific exchange areas. Here, honeycomb polymer films are obtained by the breath figure process, using well defined polymers synthesized by nitroxide-controlled radical polymerization (NMP), atom transfer polymerization (ATRP) and reversible addition/fragmentation transfer (RAFT). The photosensitizer, rose Bengal, is either post-grafted covalently to the polymer precursor, or pre-grafted to a monomer functional unit which is copolymerized with polystyrene. These syntheses lead to films with different rose Bengal concentrations. We determine the structure of the films and the location of the fluorescent dye by scanning electron microscopy and widefield and confocal microscopy. Efficiency of production of singlet oxygen was tested at a solid/liquid interface by monitoring the oxidation of dihydroxynaphthalene and α-terpinene, using UV-visible absorption spectroscopy. Honeycomb films are about five times more efficient than non-porous films of the same composition used in the same, as may be explained by their higher specific surface area and the preferential location of the photosensitizer at the film surface.

Water drops that nucleate and grow over an evaporating polymer solution exposed to a current of moist air remain noncoalescent and self-assemble into close packed arrays. The hexagonally close packed, nearly monodisperse drops, eventually evaporate away, leaving a polymer film, with ordered array of pores. Meanwhile, typical breath figures or dew that form when moist air contacts cold surfaces involve coalescence-assisted growth of highly polydisperse, disordered array of water drops. This dissertation provides the first quantitative attempt aimed at the elucidation of the mechanism of the breath figure templated assembly of the ordered arrays of pores in polymer films. The creation and evolution of a population of close packed drops occur in response to the heat and mass fluxes involved in water droplet condensation and solvent evaporation. The dynamics of drop nucleation, growth, noncoalescence and self-assembly are modeled by accounting for various transport and thermodynamic processes. The theoretical results for the rate and extent of evaporative cooling and growth are compared with experiments. Further, the dissertation describes a rich array of experimental observations about water droplet growth, noncoalescence, assembly and drying that have not been reported in the published literature so far. The theoretical framework developed in this study allows one to rationalize and predict the structure and size of pores formed in different polymer-solvent systems under given air flow conditions. While the ordered arrays of water drops present an example of dynamics, growth and assembly of spherical particles, the study on colloidal gold nanorods focuses on the behavior of rodlike particles. A comprehensive set of theoretical arguments based on the shape dependent hydrodynamics of rods were developed and used for centrifugation-assisted separation of rodlike particles from nanospheres that are typical byproducts of seed mediated growth of nanorods. Since the efficiency of shape separation is assessed using UV-Vis-NIR spectroscopy and transmission electron microscopy (TEM), the present dissertation elucidates the shape dependent parameters that affect the optical response and phase behavior of colloidal gold nanorods. The drying of a drop of colloidal gold nanorods on glass slides creates coffee ring like deposits near the contact line, which is preceded by the formation of a liquid crystalline phase. The assemblies of rods on TEM grids are shown to be the result of equilibrium and non-equilibrium processes, and the ordered phases are compared with two dimensional liquid crystals. The methodology of pattern characterization developed in this dissertation is then used to analyze the structure of the exocuticle of iridescent beetle Chrysina gloriosa. The patterns were characterized using Voronoi analysis and the effect of curvature on the fractions on hexagonal order of tiles was determined. Further, these patterns were found to be analogous to the focal conic domains formed spontaneously on the free surface of a cholesteric liquid crystal. In summary, the dissertation provides the crucial understanding required for the widespread use of breath figure templated assembly as a method for manufacturing porous films, that requires only a drop of polymer solution (dilute) and a whiff of breath! Further, the dissertation establishes the physical basis and methodology for separating and characterizing colloidal gold nanorods. The dissertation also suggests the basis for the formation and structure of tiles that decorate the exoskeleton of an iridescent beetle Chrysina gloriosa.

Open-world videogames inherently allow players a significant amount of freedomwhen traversing the in-game world. Due to this fact, level designers for such games are taskedwith the challenge of maintaining engagement and motivating exploration without drasticallyinfringing on their player agency. With this study, the authors analyzed three popular open-world games via a comparative formal analysis to determine the presence and validity of thePOI Diversity Rule, a conceptual rule for effective open-world level design proposed bySkobelev (2023), which recommends having at least three points of interests on the player’sline of horizon, offering different gameplay experiences. The authors performed this study byplotting out a route known as a “critical path”, taking panoramic screenshots within 30 secondintervals and analyzing them. The results showed that the rule is largely prevalent in all threegames. However, the conditions of fulfillment differ in terms of what categories are mostcommon, and whether static or dynamic POI are most prevalent. / Open world-datorspel ger spelare en hög grad av frihet att resa runt i spelvärlden. Pågrund av detta står leveldesigners för sådana spel inför utmaningen att upprätthållaengagemang och motivera utforskning inom spelvärlden utan att allvarligt begränsa spelarnashandlingsfrihet. I denna studie analyserades tre populära open world-spel via en jämförandeformell analys för att avgöra närvaron och giltigheten av POI Diversity Rule, en konceptuellregel för effektiv open world-leveldesign föreslagen av Skobelev (2023). Regelnrekommenderar att det bör finnas minst tre intressepunkter inom spelarens synligahorisontlinje, som erbjuder olika spelupplevelser. Författarna genomförde denna studiegenom att plotta in en rutt kallad "critical path", ta panoramabilder med 30 sekundersintervaller och analysera dem. Resultaten visade att regeln är till stor del närvarande i alla trespel. Men de specifika villkoren gällande dess uppfyllelse skiljer sig åt när det kommer tillvilka kategorier som är vanligast, och huruvida statiska eller dynamiska intressepunkter ärmest framträdande. / <p></p><p></p>

THE VOICE OF RITUAL: AN EXPLORATION TEACHING BODY AND BREATH USING THE PEDAGOGICAL PRINCIPLES OF RITUAL POETIC DRAMA WITHIN THE AFRICAN CONTINUUM By Jacquelynn Rae Camden, MFA Candidate A thesis submitted in partial fulfillment of the requirements for the degree of Master of Fine Arts Theatre Pedagogy: Voice and Speech & Ritual Poetic Drama Within the African Continuum at Virginia Commonwealth University. Virginia Commonwealth University, 2012 Major Director: Dr. Tawnya Pettiford-Wates, Theatre The focus of my undergraduate training and the concentration of my graduate work have been specifically in two areas: Ritual Poetic Drama Within the African Continuum under the tutelage of Dr. Tawnya Pettiford-Wates, and Voice and Speech with Janet B. Rodgers. I spent my undergraduate years learning and absorbing the material and philosophy of both Rodgers and Pettiford-Wates, and in my first year of graduate work, I was able to study their teaching principles and methodologies within the classroom as a teaching assistant. I was also fortunate enough to study the teaching principles of fellow graduate students within both concentrations: Ritual Poetic Drama Within the African Continuum and Voice & Speech. It is my intention with this thesis, to explain how and why I decided to integrate some of the teaching methodologies of RPDWTAC into the Second Year Voice & Speech course I taught in the fall of 2010, which focused on body and breath. It is my belief that these particular practices of Ritual Poetic Drama within the African Continuum as applied to the Junior Acting Studio are also beneficial in the pedagogy of Voice and Speech in the classroom, because such practices create an environment that encourages the building of an artistic community, personal responsibility, and the freeing of the artist’s body, mind, and spirit, resulting in the freeing of the voice as well.