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In this project, remote standoff laser spectroscopy systems working at 3-15 m have been developed for cultural heritage research, employing Raman spectroscopy, laser induced breakdown spectroscopy (LIBS), and laser induced fluorescence spectroscopy (LIF). To address the problems encountered during in situ analysis due to environmental restrictions, the adoption of remote techniques offers advantages such as convenient deployment on the ground, allowing sensitive measurements over long integration time and there is no need to redeploy for different areas of interest. The research focuses on the design and development of remote standoff laser spectroscopy systems with special needs in heritage research considered, as well as their application for in situ analysis. A remote standoff Raman system was developed and optimised. It is the first of its kind that is dedicated to cultural heritage research. It can identify most of common historic artist pigments. A daylight subtraction procedure enables the remote standoff Raman system to operate in the presence of indoor ambient light. Laser induced degradation effect was studied using various laser configurations on a range of common pigments. The remote standoff Raman system is proved to be safe for the analysis of most pigments tested when using typical integration time required for Raman measurements. In situ remote macro-Raman mapping is achieved in two field campaigns, revealing the pigments distribution on wall paintings and salt distribution in historical buildings in costal environments. A remote standoff LIBS system was developed. Assisted with Raman and reflectance spectroscopy, a multimodal approach allowing in situ standoff depth-resolved material identification of wall paintings was demonstrated for the first time. The combined elemental, molecular and reflectance information contributes to a more complete data interpretation. Consequently, the stratigraphy of whitewashed wall paintings was successfully uncovered in a unique field campaign.

Magnetic materials can host a rich variety of nanoscale magnetic structures with non-collinear spin orientations, known as topological spin textures. A plethora of intriguing phenomena entwines magnetism and topology, especially where a Dzyaloshinskii-Moriya interaction is present. Exploitations of the robust topological stability inherent in these textures promise applications in magnetic data storage and nanocomputing devices. To fully realise the potential of these spin structures, fundamental studies exploring the underlying mechanisms in real systems are essential with specific foci, including their formation, stability, transition, detection, and annihilation. The work presented in this thesis explores topological spin textures in the context of three-dimensional ferromagnets and addresses the ramifications of field-induced transitions, thermal stabilities, and associated emergent electromagnetic fields. In particular, from the three-dimensional perspective, fruitful insights are spotted by considering the depth-resolved complexity of magnetisation profiles. The first aspect of this study lies in the complex dynamics of extremely small topological defects - Bloch points, during the temporal evolutions of single topological spin textures, such as skyrmion tubes in bulk magnets and skyrmion chains in multilayers. Under the application of an external magnetic field, the transition mechanism is dominated by the combined effects of the Dzyaloshinskii-Moriya interaction and magnetostatic interaction. During the process, the Bloch-point propagation speeds are km/s. Meanwhile, the speed is periodically modulated by regular ''washboard'' potential wells that originate from the atomic arrangement, and oscillates with a THz frequency. Moreover, we report the thermal stabilities of such systems via exploration of minimum energy paths to other possible equilibrium states. It seeks to build upon the knowledge that topological spin textures can be stabilised as metastable states in a wide parameter space. The results show that the transitions are mediated by Bloch-point dynamics, where the presence of saddle points in the energy landscape is associated with the creation/destruction of Bloch points. It is notable that due to the discrete nature of magnetic systems, the topological protection property partially breaks, which leads to finite magnitudes of energy barriers. The resulting spatial and temporal non-uniformities of the magnetisation within the topological structure create emergent electromagnetic fields that act on conduction electrons. We reveal a phenomenological connection between the emergent magnetic field and three-dimensional topology, allowing unambiguous recognition of different textures based on their topological Hall signals. The transitions also bring drastic modifications to local emergent magnetic fields. It is shown that the ultra-fast propagation of a Bloch point radiates solenoidal emergent electric fields with MV/m magnitude and THz oscillation frequency. Using the understandings of the studies in this thesis, we propose several designs that seek to enable tuneabilities of thermal stabilities and ultra-fast transition phenomena. Relevant techniques are compatible with existing nanofabrication technologies. Thus, validation by future experiments should be within reach.

This thesis comprises an empirical review of the cost asymmetric behaviour and two empirical studies on cost structures in family-type organisations. In this thesis, I first introduce cost asymmetric behaviour and review the relevant literature in Chapter 2. Scholars refer to the phenomenon of cost asymmetric behaviour as "cost stickiness". This chapter includes the evidence for cost stickiness and the significant critical determinants that impact the degree of cost stickiness. In two empirical studies in Chapters 3 and 4, I explore the cost stickiness in firms based on the unique characteristics and culture of a family type of organisational structure. Because of greater alignment of owner-manager incentives, higher accounting conservatism, and being more risk-averse, research on family firms has shown that founding family firms have fewer agency problems between owners and managers than non-family firms (Shleifer and Vishny 1997; Villalonga and Amit 2006; Anderson and Reeb 2003b; Chen et al. 2010). This context provides an interesting case for examining how managerial choices in family firms can adjust resources to influence family firms' cost structure and stickiness. Chapter 3 investigates the effects of different agency problems on selling general and administrative (SG&A) cost stickiness in family and non-family firms based on the unique characteristics and culture of family firms. I use four measures of agency problems arising from CEOs' incentives, including free cash flow, CEO tenure of the first three years, CEO tenure of the final year, and the percentage of fixed pay in the CEO's total compensation. In additional tests, I examine the role of corporate governance in moderating to mitigate the effect of the agency problem on SG&A asymmetrical cost. As managers in family firms face different incentives, I conjecture that they are more likely to avoid rapidly increasing or slowly decreasing SG&A costs when sales grow or decline, respectively, compared with non-family firms. The interests of managers in family firms align with those of the owners, and that effective monitoring by the board lessens managerial empire-building incentives. Therefore, reducing agency problems of separation of ownership and control in family firms decreases the degree of cost stickiness. The results show that, compared with non-family firms, a higher free cash flow does not lessen the degree of SG&A cost stickiness in family firms. Compared with non-family firms, CEOs in the first three years of tenure are more likely to exhibit higher SG&A cost stickiness in family firms. However, CEOs in the final year of tenure are less likely to exhibit the SG&A cost stickiness in family firms. The degree of cost stickiness is more pronounced in non-family firms than in family firms when considering the CEO fixed pay percentage. Chapter 4 examines the relationship between another characteristic of family firms, risk aversion, and cost stickiness. Current literature in family firms shows that family firms are risk-averse and conservative regarding the innovative behaviour of pursuing entrepreneurial strategies compared to non-family firms (Duran et al. 2015; Jones, Makri, and Gomez-Mejia 2008; Nordqvist and Melin 2010). Family firms are often reluctant to invest in new ventures and unwilling to develop, grow, take advantage of opportunities and take risks (Habbershon and Pistrui 2002; Cabrera-Suárez, De Saá-Pérez, and García-Almeida 2001; Hall, Melin, and Nordqvist 2001). I consider five measures of risk aversion: family ownership, founder-CEO duality, CEO gender, risk tone disclosure in 10-K, frequency of management earnings guidance, and idiosyncratic risk. I also investigate the moderating role of financial constraints in firms that make family firms more risk-averse to take innovation opportunities and affect SG&A cost behaviour. The results show that higher ownership decreases the degree of cost stickiness in the active family firms and cost anti-stickiness in pooled and passive family firms. When founder-CEOs are in the active family firms, cost stickiness decreases. Female CEOs also decrease the degree of cost sticky behaviour. The more risk-averse content in risk tone disclosures from pooled family firms, the more they show cost anti-stickiness behaviour. Furthermore, the degree of cost stickiness behaviour in passive and pooled family firms is negatively associated with how frequently the company issues more management earnings guidance. The two empirical studies contribute to both management and financial accounting literature. This thesis extends the cost behaviour literature by investigating how cost management decisions are related to managers' incentives, stakeholders, and organisational culture and structure. This thesis has implications for management accountants, firm management, auditors, and analysts. They might be interested in understanding the behaviour of their expense activities (for example, when generating financial forecasts) and gaining awareness of how managers make accounting decisions to adjust their costs within a family-type governance structure in the United States.

The development of the classification systems of psychiatric disorders illustrates a long-term debate on whether a discrete and categorical or a continuum and spectral view best describes psychiatric disorders. This is because comorbidity between mental disorders is common and the symptoms of the same psychiatric disorders are heterogeneous. These all increase the difficulty to diagnose and to treat mental disorders. Generally, the diagnostic systems have attempted to develop diagnostic criteria of psychiatric disorders that resemble a solid medical model, where each disorder is described by a discrete category of symptoms. However, these attempts have been plagued by problems. Even though having a categorical classification system makes diagnoses easier than having nothing to work from, a categorical classification system cannot explain clinical conditions. Having alternative classification systems such as one based on dimensions (spectra) or a mixture of categorical and spectral classification systems may be better than using either classification system alone. It has been suggested that a mechanistic property clusters (MPC) would be a suitable alternative (Kendler et al., 2011). The MPC described psychiatric disorders are caused by multi-level causal loops and interactions. A similar view of symptoms forming a causal network – the network theory – has been advocated (Borsboom, 2008, 2017). The network theory hypothesizes that the present psychiatric symptoms are caused by the same and/or other psychiatric symptoms occurred earlier. This PhD project investigated the heterogeneous nature of the symptoms of major depression (MD) by using their repeated measures in daily-life settings in three studies. We used on-line questionnaires, mobile questionnaires, and activity sensors. MD symptoms at the moment were measured using mobile questionnaires and daily physiological signals were recorded using activity sensors. The on-line questionnaires were administered before and after the participants completed the momentary questionnaires. Study 1 measured the momentary MD symptoms using Android devices, Study 2 was a replicate of Study 1 and iOS devices were employed in Study 2. Study 3 measured the momentary MD symptoms and activity levels using Android and iOS devices and activity sensors. Study 3 was a replication of Studies 1 and 2. The replicability of the results across the three studies was tested. Meta-analysis was used to see whether there were similar patterns across studies. In addition to the network theory, discriminant and convergent validity of the mobile and retrospective MD assessments were tested. The heterogeneity of MD symptoms was examined in the relationships between momentary MD symptom ratings and controlling factors (i.e., age, gender, employment status, marital status, educational level, MD severity, circadian rhythm, personality traits and facets, daily activity and heart rate variability). The results suggested heterogeneity among MD symptoms in how they linked to other variables. These findings challenge the existing clinical practice of using the total sum-score of symptoms in clinical diagnoses. Marginal support for the network theory was reported. The findings showed moderate replicability across studies.

This study questioned whether exploitation and exploration were both "panaceas" for export performance by developing an integrated theoretical model that drew on explanations from innovation ambidexterity and the internationalization process literature. It was assumed that exploitation- and exploration-focused innovation follow two distinctive paths: efficiency-enhancing versus demand-expansion, which help explain their export performance heterogeneities. The study further investigated the implications of the geographical (i.e. domestic vs. international) proximity of knowledge-sourcing strategies in influencing the effects of exploitation- and exploration-focused innovations on export performance. Based on 852 exporting firms from the UK Community Innovation Survey (CIS) between 2010 and 2014, the investigation found opposing relationships with regards to the impact of exploitation-versus exploration-focused innovations on export performance and significant interactions in terms of the breadth of domestic and international collaborations.

This thesis studied the iron smelting technology of Southwest China. It introduces the natural and human environment of Southwest China and gives a systematic review on the important archaeological sites of Southwest China. A total of 75 iron smelting related sites of Southwest China were surveyed. Five of these sites were excavated and studied in detail including the furnace structures, smelting related materials and their smelting process. A statistical study of over 5,100 iron objects (and bronze and iron bi-metallic objects) in published excavation reports was carried out to understand the pattern and statistical distribution of iron objects excavated in Southwest China. This was followed by metallographic analysis of 66 samples taken from 42 iron objects and slags (mostly from the Lijiaba site, and from the Qiaogoutou site). The slag samples (from the Xuxiebian site) helped to identify the bowl-shaped furnaces, that discovered at the iron smelting sites of Southwest China, as refining furnaces. The results of the metallographic studies helped to characterise the range of technologies that developed in Southwest China primarily during the Han dynasty (202BC-220AD). According to these studies, some issues such as the origin and development of technology, the labourers’ identities, the origin of the blacksmiths, and the management and policy of iron production in Southwest China are discussed.

District heating and cooling (DHC) systems are attracting increased interest for their low carbon potential. However, most DHC systems are not operating at the expected performance level. Optimization and Enhancement of DHC networks to reduce (a) fossil fuel consumption, CO2 emission, and heat losses across the network, while (b) increasing return on investment, form key challenges faced by decision makers in the fast developing energy landscape. This thesis hypothesises that optimization of existing district heating networks can contribute to the development of smart thermal grids by integrating sustainable energy and intelligent management technology. This requires an accurate simulation capability at the district level factoring in building fabric and optimization of the system through energy generation, energy distribution, heat substation and terminal users. First, the thesis presents a novel concept to determine building envelope thermal transmittance (known as U-values) and air infiltration rate by a combination of energy modelling (DesignBuilder and EnergyPlus), regression models and genetic algorithm at quasi-steady state conditions. The calibrated U-values and air infiltration rate are employed as inputs in EnergyPlus to model one workday heat consumption. When compared with thermal demand from measured data, the accuracy of the calibrated model has improved significantly. Next, dynamic simulation of distribution network is demonstrated. A numerical simulation model is developed in Simulink to analyse dynamic heat losses in the pipe network at different periods of the week. Results show that heat losses vary between 1-2% during the weekday daytime, while the heat losses increase to 8-12% at other time periods. Supply and return temperatures of each building are presented and simulation results are in line with measured data. Meanwhile, Heat losses of the next generation DH are investigated based on the constructed model. Results show that lower distribution temperature and advanced insulation III technology greatly reduce network heat losses. Also, the network heat loss can be further minimized by a reduction of heat demand in buildings. Finally, a holistic district heating simulation capability is proposed. The simulation capability is carried out under the BCVTB (Building Controls Virtual Test Bed) environment. And the results display the operational schedule under the current operation scheme. Economic and environmental evaluation of the current operation scheme shows that biomass boiler is the cheapest option for heat generation due to renewable heat incentive. This district simulation capability is used to perform day-ahead optimization to determine the optimal schedules, targeting operation cost minimization. MILP is employed for optimization as it can be used to represent non-linear boiler efficiency without sacrificing the advantages brought by linear programming. Efficiency with respect to heat output level is introduced. The results indicate that smart control can be used for peak shaving, installation capacity reduction and operation cost saving. Future work involves investigating the optimization in a broader perspective sense toward smart thermal grid realization.

Over the last four decades, the research interest on foreign language anxiety (FLA) as a distinct complex of situational anxiety has been arising in EFL setting. Especially in Chinese EFL classrooms, such an anxiety is observed frequently among Chinese learners in their English speaking apprehension. Many scholars have investigated the anxiety-provoking factors to FLA or English-Speaking Anxiety in their empirical studies within different Asian contexts and findings have shown varying associations to cultural and contextual variables. However, these cultural and contextual-subjective influences on Chinese students English speaking anxiety (ESA) have not been explored extensively or specified and most importantly, little research exists for experimenting ways to a solution through systematic teaching practice. With Stern’s (1980) proposal and the researcher’s personal experience in the subject, drama approach has inspired the researcher to take the study further. Therefore this thesis focuses on formulating theories of the nature of the English-speaking anxiety experienced by Chinese learners of English, establishing the relation between the anxiety and drama approach, and exploring the influence of a specifically-designed drama class intervention in a higher education setting. The research questions aim to answer how the level of the participants’ anxiety is influenced by the diverse factors situating in this drama English class, e.g. classroom social factors, cultural variables, teacher and learner variables. In addition, this study aims to identify the crucial factors to the ESA experienced in the Chinese context as for explicating the cultural-situational dimension and how this relates to the application of drama approach. This study reflects the nature of action research and adopts mainly qualitative and partially quantitative data collection procedures. The field work took place in a Chinese university over a period of three months. The researcher designed the course and worked as the teacher of a random group of thirteen students who reported the anxiety. The survey was included as part of the questionnaire to assess the participants’ general ESA levels, selected and reformed on existing scales. Qualitative data was obtained from the teacher’s journals, observing the class and interviewing every participant. Both group results and three individual cases were presented and analysed. The findings of this research suggest that this drama course has a positive effect on reducing participants’ anxiety to various degrees. Three types of change in the anxiety level were revealed as drastic, fluctuated and mild decrease. The decrease in anxiety was explained by the increase in self-confidence through repeated conversation rehearsals of drama plays as oral practice in a learner-friendly language environment. The potentials of creating learning interest, effective collaboration and interaction contributed to a supportive language environment, which helped the reversal of vicious cycle of ESA. The teacher’s role is also essential in facilitating such a friendly learning environment. The predictors of the anxiety are shown to link to socio-psychological factors interacting with classroom social variables. Self-confidence was found to greatly influence the anxiety level and the willingness to communicate, which was directly or indirectly connected to fears of negative evaluation, public attention, face-protection and face loss. The lack of experience in learning and using oral English was highlighted as the main source of the anxiety to affect the self-confidence. This study furthers the understanding of ESA construct in the Chinese context, and contributes to increase the methodological and socio-geographical diversity in both FLA research and action research for language programme development in drama approaches.

With continued advancement in semiconductor manufacturing tech- nologies, process variations become more and more severe. These variations not only impair circuit performance but may also cause po- tential hazards in integrated circuits (IC). Asynchronous IC design, which does not rely on the use of an explicit clock, is more robust to process variations compared to synchronous design and is suggested to be a promising design approach in deep-submicron age, especially for low-power or harsh environment applications. However, the correctness of asynchronous circuits is also becoming challenged by the shrinking technology. The increased wire delays compared to gate delays and threshold variations could bring glitches into the circuit. This work proposes a method to generate a set of su cient timing constraints for a given speed-independent circuit to work correctly when the isochronic fork timing assumption is lifted into a weaker timing assumption. The complexity of the entire process is polyno- mial to the number of gates. The generated timing constraints are relative orderings between the transition events at the input of each gate and the circuit is guaranteed to work correctly by ful lling these constraints under the timing assumption. The benchmarks show that both the number of total constraints and the constraints that are only needed to eliminate strong adversary paths are reduced by around 40% compared to those suggested in the current literature, thus claiming the weakest formally proved condi- tions.

The purpose of this study was to explore why and how stories and drama can encourage children’s participation in class and also affect their learning of English as a foreign language in Taiwanese primary schools. The author takes a strong interest in both fields, English for Young Learners (EYL) and educational drama, and attempts to propose a solution, story-based drama, to two of the more common problems faced by teachers at primary level—mixed ability classes and limited teaching hours. The key methodological approach was action research in a case study format, using mixed methods and gathering quantitative as well as qualitative data in order to evaluate the impact of the author’s teaching on the children’s English learning. The quantitative research data was gathered with the aid of questionnaires responded to by one hundred and nine teachers and thirty-two fifth graders, while the qualitative data was collected from interviews, participant observation, fieldnotes, journals, artefacts, and video and audio recordings. Quantitative and qualitative data analyses revealed that the incorporation of stories and drama into the existing school curriculum was workable, and the story-based drama assisted the pupils to have greater participation in class and a higher degree of improvements than before in terms of their four language and non-verbal communication skills. This was corroborated by questionnaire results, interviewees’ responses, the co-teacher’s observations, and the pupils’ written work. The author recommends that a collaborative approach to curriculum design and research methodology could be adopted by teachers themselves or between teachers and researchers in order to stimulate more research on the use of story-based drama in similar contexts, while deepening our understanding of this resourceful teaching approach.

Zeolites have been used as catalysts in a number of industrial processes for the last half century. The photooxidation of hydrocarbons on cationic forms of zeolites is one area of research that has recently attracted growing interest. In this work the selective oxidation of I-butene on cationic forms of zeolites was achieved in the presence and absence of light, at temperatures ranging from 30-IOO°C. The latter was performed successfully both in a static and continuous tlow system, monitored by Fourier transform infrared spectroscopy and diffuse reflectance infrared spectroscopy respectively. Of the samples tested the most informative results were obtained from experiments employing Y zeolites, which possessed pores and cages of adequate size to allow for reaction to take place, with minimal amounts of acid sites thereby preventing the occurrence of competing polymerisation reactions. By utilising UV diffuse reflectance it was possible to observe the charge-transfer state of I-butene and oxygen on the more reactive materials. The products of I-butene oxidation were then employed in a series of adsorptiondesorption experiments on cation-exchanged forms of zeolite Y. This study showed that the removal of such products intact from a zeolite suhstrate was difficult, with complete desorption from some samples only at 350°C, and in some cases the procedure was complicated by decomposition and transformation of the sorbates. An investigation into the structure of SrY and its relationship with adsorbed ethylene was performed utilising X-ray diffraction (XRD) with synchrotron radiation. A study with similar objectives was also carried out via a computational approach, which utilised NaY and I-butene as the host and guest respectively. The findings from both analyses suggested that the extra-framework cations and guest molecules were in close III proximity of one another, with the XRD study indicating the possibility of cation migration from the smaller cages to the supercages upon adsorption of ethylene. Overall, this research has shown that the partial oxidation of short-chain hydrocarbons was possible without the addition of sensitisers and in mild conditions; the electrostatic fields generated by the extra-framework cations were sufficient for a reaction to take place, and for divalent cations this occurred even in the absence of a light source. The removal of oxidation products was more problematical. Consequently, the concentration of cations present in the zeolite proved to be a significant factor in both the zeolite's reactivity and the retention of the products formed.

Bovine coronaviruses (BCoVs) are important members of the Betacoronavirus genus, Embecovirus subgenus in Orthocoronavirinae subfamily within the Coronaviridae family. They can cause enteric or/and respiratory diseases in cattle. However, the mechanisms for BCoV tissue tropism and pathogenesis are still unknown and could be due to interactions of viral, host, and environmental factors. There are limited studies to investigate whether co-infection with other bovine pathogens, environmental factors (such as season of the year) and host factors (such as beef vs dairy; age, such as pre- vs post-weaning; and the level of pre-existing BCoV antibodies) contribute to enteric or respiratory tropism. In our study, we isolated recent BCoV strains and compared them with historical strains to study the evolution of BCoVs. Bovine fecal samples were collected from dairy calves, dairy cows, and beef cattle in Georgia by Dr. Palomares Lab at the University of Georgia. Bovine fecal and nasal samples from asymptomatic veal calves from an Ohio farm were provided by Dr. Habing’s Lab at The Ohio State University. We detected BCoVs from both nasal (n=10) and fecal samples (n=156) and isolated BCoV strains from enteric samples. The BCoV genomic sequences of five strains BC7, BC8, BC9, BC39, and BC47 were characterized, and they all belong to genogroup II by phylogenetic analyses. Sequence analyses were performed to compare the mutations between the historical and current viruses and between the viruses isolated from respiratory and enteric samples. We found that one pair of samples BC8 and BC18 from the same calf, but different collection sites (fecal and nasal sites), showed two amino acid differences in the spike (S) protein; We predicted the locations of these two amino acid residues in the 3D protein structures. Reverse genetics is a state-of-the-art technology to study viral factors, but until now no infectious clones have been generated for BCoVs, and this has hampered in-depth research on disease mechanisms and vaccine development. In our study, we are constructing an infectious clone for BCoV. We will introduce the viral genomic RNA (gRNA) into HRT-18 cells to generate the infectious clone-derived BCoV (icBCoV). The construction of this platform will enable future studies of which viral genes are critical for its virulence, tissue tropism, and antagonism to host innate immunity. Our long-term goal is to develop approaches to prevent and control BCoV infections to improve cattle health.

This timely study is an investigation of the English language learning experiences and related empowerment capabilities and deprivations of female rural migrant TVET students in two locales in Western China at macro, mezzo, and micro levels during the years of the great expansion of the TVET school system. This study adopted basic interpretive research using semistructured interviews and field observations. The capability approach provided the conceptual framework for designing interview questions and analysis. The macro level entailed the history of English language learning in China, English instructional policies, and access to language learning and resources. The mezzo level involved sociological influences relevant to rural migrant youth’s studying of English: peer environment, family capital, English teachers, and teaching methods. The micro level encompassed individuals’ voices and experiences of learning English, and their formulation of related constitutive and instrumental capabilities. Multilevel analysis revealed that for rural migrant youth, learning English presented a hurdle to further education and created a consistent educational attainment gap. It also reflected unequal access to opportunities and resources as well as the unequal distribution of power, privilege, and capital shaped by the residence control (hukou) system. English exams had become not only the bottleneck for migrant students’ educational advancement but also delimited employment opportunities. The underfunded and underresourced rural school was a key creator of social inequality and rural deprivation. Recommendations include reformulating the national English education policy, allocating more resources to English learning, improving English teacher training in rural schools, and adapting TVET English curriculum to economic imperatives.

T cells are integral to the adaptive immune response against foreign pathogens and tumor cells. They respond to foreign substances, termed antigens, that can elicit immune responses. After becoming activated due to recognition of antigens presented by professional antigen-presenting cells (APCs), T cells can mount multiple effector functions, such as cytotoxic activities, which eliminate infected cells and tumor cells, and helper activities that assist other immune cells’ responsiveness. Memory T cells, which differentiate upon antigen encounter, respond rapidly to subsequent antigen exposure and provide long-lasting protection against pathogens. While one T cell can recognize few antigens, T cells collectively can recognize and respond to a very diverse array of antigens. This unique property by which T cells recognize and respond to a myriad of antigens stems from the rearrangement of their T cell receptor (TCR) genes during development. The highly random TCR rearrangement during development gives each T cell a unique TCR that can recognize a specific antigen, and collectively, the entire T cell repertoire is able to respond to a wide range of antigens. However, autoreactive T cells, which express TCRs that recognizes normal antigens found in the host, could potentially arise from this TCR rearrangement process, posing a potential risk of mounting an autoimmune reaction and damaging the host’s healthy tissues and organs if released to the periphery. The immune system has multiple tolerance mechanisms in place to prevent autoimmunity, and one such tolerance mechanism, termed central tolerance, works by inducing apoptosis of developing autoreactive T cells or by diverting them to the suppressive regulatory T cell (Treg) lineage. T cell development takes place in the thymus. Developing T cells (thymocytes) migrate through the thymic cortex and the medulla at different developmental stages, interacting with and receiving differentiation, proliferation, and selection cues from different thymic stromal cells. After being positively selected for correctly rearranged TCRs that are able to bind self-peptide:MHC complexes expressed by the host, thymocytes migrate from the cortex into the medulla, where they interrogate medullary stromal cells including medullary thymic epithelial cells, dendritic cells (DCs), and B cells. These medullary stromal cells express, process, and present a broad range of self-antigens. Thymocytes that react strongly to the presented self-antigens undergo apoptosis, a process referred to as “negative selection”, or they differentiate into Tregs, thereby removing autoreactive T cells from the naïve T cell repertoire and establishing central tolerance. Chemokine receptor signaling contributes to the orchestrated movement and localization of thymocytes, and their interaction with thymic stromal cells at different development stages. Chemokine receptors are G-protein coupled receptors that respond to a family of small cytokines termed chemokines. Thymocytes upregulate different chemokine receptors at various development stages and receive chemokine cues from different thymic stromal cells. Chemokine receptor signaling plays an important role in thymocytes’ directional movement, speed changes and interactions with thymic stromal cells. Some thymic stromal cells also express chemokine receptors, which may facilitate their own survival, differentiation, and localization within the thymus. The mechanism by which chemokine receptor signaling contributes to the establishment of central tolerance is not fully elucidated. In this dissertation, I will report on the distinct roles of the chemokine receptors CCR4 and CCR7 in the establishment of central tolerance in the thymus. While the role of CCR7 in central tolerance has been relatively well-characterized, the contribution of CCR4 to this process is not well understood. Both CCR4 and CCR7 are expressed by thymocytes after positive selection, raising the question of whether these two chemokine receptors have distinct or redundant impacts on medullary accumulation and tolerance of post-positive selection thymocytes. In Chapter 2, I investigate the roles of CCR4 and CCR7 expression on thymocyte negative selection. Our data reveal a striking disconnect between CCR7 expression and function on intermediate post-positive selection thymocyte subsets, arguing against the consensus in the field that CCR7 expression decisively locates thymocytes to the medulla. Instead, we find that thymocytes express CCR4 within hours of positive selection signaling and swiftly migrate into the thymic medulla in a CCR4-dependent manner, days before CCR7 expression begins. Additionally, CCR4 and CCR7 promote medullary accumulation of immature versus mature post-positive selection thymocyte subsets, and contribute to early versus late phases of negative selection, respectively. The contribution of CCR4 to central tolerance against activated APCs is then highlighted. Collectively, this study suggests a layered model of central tolerance in which CCR4 directs medullary migration and negative selection of immature post-positive selection thymocytes, and CCR7 directs medullary migration and negative selection of more mature post-positive selection thymocytes. The exact mechanism by which chemokine receptors regulate Treg generation in the thymus is not fully understood. In Chapter 3, I investigate the impact of CCR7 expression on thymic dendritic cells (DCs) on the thymic Treg compartment. An increase in Treg generation in thymus was discovered in Ccr7 [superscript -/-] mice. Surprisingly, CCR7 deficiency in the thymic DC compartment, rather than on the thymocytes, contributed to the increased Treg generation in Ccr7 [superscript -/-] mice. CCR7 is expressed by MHCII [superscript hi] thymic conventional DCs (cDCs) of both the Sirpα⁻ cDC1 and Sirpα⁺ cDC2 lineages. Ccr7 deficiency does not alter the cell-intrinsic potential of different DC subsets to induce Treg; however, CCR7 deficiency results in increased apoptosis of MHCII [superscript hi] Sirpα⁻ DCs and a relative increase of MHCII [superscript lo] Sirpα⁺ DCs, which possess the greatest potential to induce Tregs of all thymic DC subsets. This study reveals that CCR7 deficiency alters the composition of the thymic DC compartment, thus dysregulating the induction of Treg. Together, my studies further elucidate the contribution of chemokine receptor signaling to the maintenance of central tolerance in the thymus and provide additional insights into the understanding of mechanisms underlying autoimmune diseases.

A common and serious complication of radiation treatment for cervical cancer is vaginal stenosis, defined as the narrowing or shortening of the vaginal canal. Prior studies have found that vaginal dilators can be an effective early treatment for vaginal stenosis but suffer from low patient adherence due to pain and discomfort. Inflatable silicone balloon dilators have recently been designed and implemented in the Talke lab to address low patient adherence of traditional dilators. By taking advantage of the high flexibility of silicone and the continuously adjustable size of an inflatable balloon, the new dilator design reduces pain and discomfort for the patient. To simulate a stenosed vaginal canal and evaluate the efficacy of the inflatable dilator, we have built a vaginal model using a specially designed composite material consisting of silicone and thermoplastic polyurethane. This material can create a vaginal phantom with stiffness variation. The two-material composite allows us to tune the stiffness of our vaginal tissue analog, a critical symptom of vaginal stenosis. This thesis investigates this newly designed composite material of silicone and thermoplastic polyurethane to help in the understanding of the treatment of vaginal stenosis. Investigating how stenosed vaginal tissue reacts to an inflatable dilator will be a guide to clinical applications and the assessment of vaginal stenosis. Tensile coupons were manufactured and tested with a uniaxial tensile tester and a digital image correlation setup. The constitutive equations for the silicone-polyurethane composite were determined and analyzed in terms of Mooney-Rivlin coefficients for hyperelastic materials.

In his work on crystal bases [13], Kashiwara introduced a certain degeneration of the quantized universal enveloping algebra of a semisimple Lie algebra g, which he called a quantum boson algebra. In this work, we construct Kashiwara operators associated to all positive roots and use them to define a variant of Kashiwara’s quantum boson algebra. We show that a quasi-classical limit of the positive half of our variant is a Poisson algebra of the form (P=C[n∗], {,}P), where n is the positive part of g and {,}P is a Poisson bracket that has the same rank as, but is different from, the Kirillov-Kostant bracket {,}KK on n∗. Furthermore, we prove that, in the special case of type A, any linear combination a1{,}P+a2{,}KK, a1,a2∈C, is again a Poisson bracket. In the general case, we establish an isomorphism of P and the Poisson algebra of regular functions on the open Bruhat cell in the flag variety. In type A, we also construct a Casimir function on the open Bruhat cell, together with its quantization, which may be thought of as an analog of the linear function on n∗ defined by a root vector for the highest root.

Candida glabrata is the second most common cause of invasive candidiasis. Intrinsic resistance has greatly limited the utility of the triazole antifungal, fluconazole, in the treatment of invasive fungal infection. The transcription factor Upc2 regulates the expression of sterol biosynthesis genes in yeast. Disrupting UPC2A in C. glabrata greatly increases its susceptibility to fluconazole (FLU) in both FLU-susceptible and -resistant clinical isolates. Therefore, the Upc2A and its target genes represent a potential pathway for overcoming FLU resistance in C. glabrata. We aimed to delineate the Upc2A regulon to determine its target genes involved in FLU resistance. Transcriptome sequencing (RNA-seq) analysis was used to compare gene expression profiles of: a) wild-type (WT) strains with and without UPC2A under non-stressed conditions; b) those same strains treated with three sterol biosynthesis inhibitors (SBIs; FLU, terbinafine, fenpropimorph); and c) strains with an activating mutation (GOF) in UPC2A. Global chromatin Immunoprecipitation (ChIP-seq) was used to identify genes whose promoters were bound by Upc2A in strains carrying WT and GOF alleles of Upc2A with and without fluconazole exposure. Only three genes (UPC2A, ERG25, and ERG3) were found to be downregulated in the absence of UPC2A. Sixteen genes were commonly upregulated in response to SBIs’ treatment in a Upc2A-dependent way, including ERG2, ERG3, and ERG11, the promoters of 10 of which were bound by Upc2A. A total of 15 genes were upregulated, including ERG2, ERG3, ERG25, and ERG11 in the strain containing GOF mutation and the promoters of 6 of these genes were bound by Upc2A. Based on our data, ERG3, ERG11, HEM13, and CAGL0H09592g (ScTIR1) could be potential targets of Upc2A in C. glabrata. This more comprehensive understanding of the Upc2A regulon in C. glabrata may eventually lead to strategies to overcome FLU resistance and enhance fluconazole activity against this important fungal pathogen.

In the early nineteenth century, the most important environmental issues were not a widespread concern. Humans believed that resources in the planet seemed immeasurably vast, and that nature itself would digest everything and continue to grow. In recent years, our understanding of nature has dramatically changed. We are now facing several environmental issues such as shortage of resources, pollution and waste generation. More and more people are starting to realize that today environmental problems are not simple environmental problems, but design problems. Therefore, increasing the sustainability of products has attracted public attention greatly in recent years. However, when most designers suggest how to make the product more sustainable, they neglect the importance of product life extension. “In many cases, longer-lived products could save resources and generate less waste and increase the sustainability of products significantly, because fewer units are needed to satisfy the same needs.” (Keoleian & Menerey, 1994, p. 656) There are several ways to meet the need to extend product life. Cultural factors have the most crucial influence on the extension of product life. This thesis focusses on building the relationship between cultural elements in the product and sustainability, and how to use cultural elements to increase the product’s sustainability. Finally, this thesis will generate guidelines to help product designer to create a sustainable product or improve the sustainability of their design with the use of cultural elements. By following the guidelines, the designer has the opportunity to create holistically sustainable product, providing a new method to address severe environmental problems while at the same time ensuring the profit of the manufacturer.

Sonatina for Clarinet Solo (1956) / Csaba Deák -- Clarinet Sonata in E-flat Major, Op. 120, No. 2 (1894) / Johannes Brahms -- Sonata in D Major, Op. 94 (1943) / Sergei Prokofiev ; arr. Kent Kennan

Security has become one of the most significant concerns for our cyberspace. Securing the cyberspace, however, becomes increasingly challenging. This can be attributed to the rapidly growing diversities and complexity of the modern cyberspace. Specifically, it is not any more dominated by connected personal computers (PCs); instead, it is greatly characterized by cyber-physical systems (CPS), embedded systems, dynamic services, and human-computer interactions. Securing modern cyberspace therefore calls for a multi-faceted approach capable of systematically integrating these emerging characteristics. This dissertation presents our novel and significant solutions towards this direction. Specifically, we have devised automated, systematic security solutions to three critical aspects of our modern cyberspace including i) cyber-physical systems, ii) dynamic web services, and iii) social networks. This dissertation makes the following contributions. First, we have conducted systematic vulnerability assessment for a real-world, complex CPS, namely Unmanned Systems Autonomy Services (UxAS). Our assessment has identified a set of exploitable vulnerabilities. Second, we have designed an adaptive traffic morphing algorithm to conceal CPS communications into background network traffic. Third, we have designed a CPS self-destruct model and studied the security-and-performance trade-off using probabilistic model checking. Fourth, we built a novel detection system to detect PHP-based malicious web shells. Finally, we have designed a novel detection system to detect suspicious behaviors in an online emotional support system.

My dissertation comprises two chapters. The first chapter is an empirical study of government spending effects in both developed and developing countries. Based on the panel structural VAR analysis and the sign-restriction method for identifying the government spending shock, I find that private consumption increases in response to a positive government spending shock in both groups, yet such consumption effect is greater in developing than industrial countries; the response of real effective exchange rate to the government spending shock varies across groups: it depreciates in developed countries and appreciates in developing countries.

Suite from The soldier's tale : for clarinet, violin and piano / Igor Stravinsky (with: Sean Riley, violin, and Q Langman, piano)-- Selections from Eight pieces for clarinet, cello and piano, op. 83 / Max Bruch (with: Kelvin Lee, cello, and Q Langman, piano) -- Clarinet quintet in B-flat major, op.34 / Carl Maria von Weber (with: Changming Li, William Lee, violin ; Chu Young Kim, viola ; Kelvin Lee, cello) .

Fantasia on the opera Un ballo in maschera by G. Verdi : op. 46 / Donato Lovreglio -- 4 pieces in bird shape : op. 18 / Takashi Yoshimatsu -- Abîme des oiseaux / Olivier Messiaen -- Clarinet concerto / Jean Françaix.

Antibiotic resistance (AR) has emerged as one of the major global public health challenges in recent years. The primary mitigation strategy nowadays focuses on limiting the use of antibiotics in human medicine and agricultural production, including eliminating the growth promotional uses of antibiotics in food animal production. However latest studies have found that multiple risk factors are contributing to the AR problem seen today. Thus an improved understanding on critical AR risk factors is necessary for effective AR mitigation. The first chapter of the dissertation provides a review of relevant literature. After a short summary for the rationale and research objectives of the Ph.D. project, the third chapter presented the results from the study that illustrated the profiles of fecal microbiota and AR in zoo animal feces. Since zoo animals were not subjected to growth promotional antibiotics, the prevalence and abundance of AR in zoo animal feces illustrated the contribution of additional risk factor(s) other than the applications of antibiotics to AR ecology. Fourteen zoo animal subjects were examined. Phenotypically resistant microflora were detected in all animal subjects, while the prevalence and abundance of AR varied among different animal subjects. Meanwhile, total fecal DNAs were extracted for profiling the fecal microbiota and AR genes. Bacterial amplicon libraries were constructed and sent for Illumina MiSeq. Data from amplicon sequencing showed that gut microbiota in carnivores and herbivores had distinctive profiles. Total DNAs were pooled into two samples, being carnivores and herbivores, respectively, and subjected to Illumina HiSeq. Results illustrated that both carnivores and herbivores harbor AR genes in fecal microbiota, with slightly higher abundance in carnivores. Meanwhile, the profiles of AR genes varied between carnivores and herbivores, indicating the the effect of potential risk factors on AR ecology in animal GI tract system. Chapter Four examined the potential impact of food animal production operation in sheep from northwest China. In common sheep practices, antibiotics were not used as growth promotors. Two types of operation practices were examined, including commercial farm and family operations. Commercial farms were large-scale, using commercial feed including soy, corn, and alfalfa. For family operations, small sheep herds were raised in meadows of mountain areas. Four commercial farms and five family operations were involved in the study. Sheep feces were collected and subjected to resistant bacteria recovery on medium supplemented with antibiotics. Phenotypically resistant bacteria were found in all animal subjects, while the prevalence of resistant bacteria to different antibiotics varied. Total fecal DNAs were extracted and sent for Illumina HiSeq sequencing. The sequencing data were analyzed for fecal microbiota compositions and AR gene profiles. The profiles of fecal microbiota from commercial farms and family operations represented two distinct groups, indicating the impact of operation practices on the fecal microbiota composition. Resistome analysis showed that AR genes were less abundant in sheep fecal microbiome of family operations comparing to those of commercial farms. Results from this study suggested the influence of operation practices on AR ecology in food animal gut as well.

Digital curation is an emerging topic of interest in the current museum development. If on-site museum experience can be enhanced by digital technology, the development of digital curation in cultural expression can not only promote the role of museum in this digital era but also boost the value of cultural heritage more than ever before. This research focuses on the development of digital curation in cultural expression applications, such as museums and art galleries, with special attention to the user experience perspective. The goal is to provide a novel approach that helps to enhance visitors’ on-site museum experience through digital technology. We illustrate how the use of technology can improve the production process and increase the interaction and personalization between visitors and collections by evaluating a prototype that is developed based on this principle.

"While the priest climbs a post, the devil climbs ten". The problem size gets larger as computers become faster. Using naive algorithms, even equipped with fast CPUs and large memories, computers still cannot handle many problems of certain size. Some searching tasks, however, can be answered with the help of the algorithmic technique, such as time and space trade-off.

This project applies the concepts of computer-based decision support system (DSS) to a planning project, Interstate 71 Corridor Study in Metropolitan Cincinnati Area. The final product will be a planning decision support system for two major issues in transportation planning: congestion control and emission-concentration estimation. This DSS will consist a geographic information system (GIS) of study area and a set of Graphic User Interface (GUI). It will allow planners and other decision-makers to select planning alternatives for specific areas and compare results. Four methodologies will be used: 1) geographic information system applications, 2) virtual reality technology, 3) quantitative analysis with mathematical models, and 4) object-oriented programming.

The present study examined the association between psychopathology and substance abuse using the Youth Self-Report scale. To ensure the psychometric properties of the YSR scale, its factor structure derived by Achenbach was evaluated. The data obtained from a three year follow-up study of adolescents hospitalized for psychiatric treatment was used to test the hypotheses set forth in the study. The data was collected using a nonexperimental research design at three points in time. In the study, time 1 data was utilized for generating the initial findings, and time 2 for cross validation. Time 3 data was not used because the sample size was too small. The study confirmed part of Achenbach's findings in that four first order factors remained unidimensional; they are Somatic Complaints, Anxious/Depressed, Thought Problems, and Attention Problems. However, subdimensions were further derived for Social Problems, Delinquent Behaviors, and Aggressive Behaviors. Additionally, Social Problems, Thought Problems, and Attention Problems were found cross loaded on both Internalizing and Externalizing scales. The results of the tests for the structural models revealed that the measures of psychopathology explained significant amount of variance in substance abuse for the total sample and for the girls (29% and 36%, respectively), whereas explained variance was only 10% for the boys. Externalizing had significant effect on substance abuse; among the first order factors, Delinquent Behaviors, Aggressive Behaviors, Attention Problem were the three predominant predictors of substance abuseThe results of discriminant function analyses demonstrated the usefulness of the YSR in classifying substance abusers among adolescents with psychiatric disorders. For the girls, it enhanced the classification accuracy 34 percent greater than that achieved by chance; whereas, for the boys, for boys, 26 percent greater than chance. The study found that the gender differences were not on the types of psychopathology associated with substance abuse, but the extent of the differences between substance abusers and nonsubstance abusers. The differences were larger among the girls. Finally, the initial findings based on time 1 remained stable on time 2 for both the measurement model of the YSR and the structural model

The study is to develop a historically oriented physical science curriculum model for the high schools in Taiwan. Taiwan is changing into a pluralistic society, in which the learners must be confronted with certain conflicts of the beliefs, values, and ideology raised by science and technology. Historical approach in science teaching has been identified as effective in helping the learners understand the nature of science in the social and cultural context. Also, science teachers in Taiwan have recognized that a historically oriented science curriculum model is in the needs of their teaching but the history of science hardly can be integrated into the current science curriculum. A historically oriented curriculum model can make a contribution to practical science teaching. The methodology of developing the curriculum model follows the Tyler Model. The study reviews the history of science in science curriculum development. The preliminary objectives of the curriculum model are suggested through investigating the nature of science, the learners' life, society and culture in Taiwan, and science education in Taiwan. Obtaining the objectives of the curriculum model, the study screens the preliminary objectives through philosophic assumptions and psychological basis of the curriculum model. According to the objectives of the curriculum model and the review of the history of science in science curriculum development, the science learning experiences consisting of historical approach are selected. Then, the selected learning experiences are organized according to psychology of learning. The concepts, skills, and values of the organization of learning experiences must be identified with the factors: continuity, sequence, and integration. The evaluation procedures of the curriculum model are developed based on the objectives of the curriculum model. Finally a diagram of the curriculum is developed to illustrate the curriculum model.