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Influenza A virus (AIV) has an extremely high rate of mutation. Frequent exchanges of gene segments between different AIV (reassortment) have been responsible for major pandemics in recent human history. The presence of a wild bird reservoir maintains the threat of incursion of AIV into domestic birds, humans and other animals. In this thesis, I addressed unanswered questions of how diverse AIV subtypes (classified according to antigenicity of the two surface proteins, haemagglutinin and neuraminidase) evolve and interact among different bird populations in different parts of the world, using Bayesian phylogenetic methods with large datasets of full genome sequences. Firstly, I explored the reassortment patterns of AIV internal segments among different subtypes by quantifying evolutionary parameters including reassortment rate, evolutionary rate and selective constraint in time-resolved Bayesian tree phylogenies. A major conclusion was that reassortment rate is negatively associated with selective constraint and that infection of wild rather than domestic birds was associated with a higher reassortment rate. Secondly, I described the spatial transmission pattern of AIV in China. Clustering of related viruses in particular geographic areas and economic zones was identified from the viral phylogeographic diffusion networks. The results indicated that Central China and the Pearl River Delta are two main sources of viral out flow; while the East Coast, especially the Yangtze River delta, is the major recipient area. Simultaneously, by applying a general linear model, the predictors that have the strongest impact on viral spatial diffusion were identified, including economic (agricultural) activity, climate, and ecology. Thirdly, I determined the genetic and phylogeographic origin of a recent H7N3 highly pathogenic avian influenza outbreak in Mexico. Location, subtype, avian host species and pathogenicity were modelled as discrete traits and jointly analysed using all eight viral gene segments. The results indicated that the outbreak AIV is a novel reassortant carried by wild waterfowl from different migration flyways in North America during the time period studied. Importantly, I concluded that Mexico, and Central America in general, might be a potential hotspot for AIV reassortment events, a possibility which to date has not attracted widespread attention. Overall, the work carried out in this thesis described the evolutionary dynamics of AIV from which important conclusions regarding its epidemiological impact in both Eurasia and North America can be drawn.

It is important to develop methods to search for photons in the ultra-high energy cosmic ray beam. Photons above 6 × 10^18 eV can be created if the highest energy cosmic rays are dominated by light nuclei (such as protons) but not if the primaries are dominated by heavy nuclei such as iron. In this thesis a new method is developed to attempt to distinguish showers initiated by photons from those initiated by hadrons. Data from January 2004 to March 2014 that have zenith angle 0 < θ < 60 ̊ are used in the analysis. This is the first time that a parameter based on the surface detectors from the Pierre Auger Observatory is valid for the entire zenith angle range and even for energies below 10^19 eV. 81, 9, 2, 0 and 0 photon-like events were found for the energies above 10^18.8, 10^19, 2 × 10^19, 3 × 10^19 and 4 × 10^19 eV respectively (all photon candidates are considered as hadronic background). The upper limit (95% c.l.) of the photon flux compared to previous analyses that were obtained by other methods has been improved by a factor of 3.

This dissertation examines the interface between music and language in "Huju", which is a Shanghai dialect based regional opera. Chapter I is a short introduction. Chapter II presents a thorough review of the studies on linguistic tone and music tune, and provides descriptive background information about "Huju" and Shanghai dialect. Chapter III introduces the theory of prosodic phonology and its related studies on Shanghai dialect. Chapter IV presents a quantitative research on the mapping conditions via comparing the music melody and linguistic tone in "Huju" within the prosodic domains. Chapter V presents the linguistic Optimality Theory(OT) analysis to study about the music structure in "Huju" based on the Generative Theory of Tonal Music (GTTM). Chapter VI summarizes the findings and conclusions. This dissertation tries to solve the following questions: 1) Does music follow melody in tonal language or is there a mismatch between them? 2) If there is a mismatch between music and language, what causes such mismatch and how are music still be understood, and 3) What interface area can be studied between music and language? "Huju", as a dialectal opera with moderate tonal system of five tones, is the research subject. For the quantitative study, a metric, including melodic, syllabic and tonal tiers with tone-melody matching rules within prosodic units has been proposed. After analyzing through different prosodic domains, including Prosodic Word(PW), Clitic Group(CG), Phonological Phrase(PPh), Intonational Phrase(IP) and Foot(Ft), the results suggest that there is a high correspondence between music melody and language tone in "Huju", and the fewer tones a language has, there tends to be fewer possibilities to link tone and music melody. The OT analysis provides the comparison on the innate structure between music and language, and suggests that music resembles language from innate structure in certain ways with constraints. A discussion about the well-formedness and preference rule in music and language is also provided. This dissertation provides a new model of studying the tone-tune relationship in tonal language, and moreover, it is may fill in the gap in the interface studies between music and language in Chinese languages. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

The main subject of this thesis is the exceptions in documentary credits in English law. The exceptions were established during the development of the documentary credits system to solve drawbacks of the payment means caused by its distinctive feature of autonomy. A rationale of the research is the current decline of the market share of documentary credits as a recognized means of settlement in international trade. This thesis aims to explore an appropriate and efficient way to apply certain necessary exceptions in documentary credits system. And hopefully, the current high rate of the rejection of the documents by banks by relying on the strict compliance principle can be decreased by the improving of the application of exceptions in documentary credits. The research centres primary the application of the exceptions in English law. An early study of the original development of the fraud exception will cover both English and American authorities. Because there is no statute law in English law to regulate the exceptions in documentary credits, the thesis will analyse the exceptions mostly through the case law. The main exceptions analysed in the thesis are the fraud rule, the illegality exception and the nullity exception. The application pattern for the three exceptions will be worked out respectively; the specific application of the injunction rules in applying the fraud rule will be concluded during the analysis of the fraud rule; some common features in the application among the exceptions will also be summarized in the thesis. An effort is made to suggest a prospective development of exceptions, which is in consistent with the autonomy principle. And as the necessary exceptions are applied efficiently, the disputes existing in documentary credits system currently may be settled without the appliance of any explanatory rules.

Outsourcing customer services abroad has become an important strategy for multinational firms. The service offshoring research suggests that consumers generally hold a negative response towards outsourcing abroad, but this varies depending on the location of the outsourced services (i.e. the COO effect). One noticeable aspect overlooked in this literature is to whom the service is outsourced, and the subsequent fit between the focal firm and its outsourcing partner. This perspective moves beyond COO effects and looks to the fit between the focal firm/brand and the foreign outsourced partner. In this thesis, the focal construct, namely, the perceived fit is developed and validated by examining the antecedents and consequences of it on responses of consumers. In addition to examination of the direct effects of service outsourcing, this thesis adds to the literature by also examining the mediating effects of customer certainty. Furthermore, this research incorporates two forms of individual-level differences, uncertainty avoidance and individual self-construal, in examining their moderating effects in the context of service outsourcing. Last but not least, in this thesis, two forms of marketing communication strategies, namely, customer-focused and society-focused communications were examined in the effectiveness of enhancing responses of consumers to the service outsourcing. This study concludes the following findings. First, the results concluded that perceived fit comprises three dimensions: cultural similarity between the host country and home country, corporate reputation of the partner, and advanced technology owned by the partner. Further testing also confirmed the mediating role of customer certainty. It is also found that uncertainty avoidance varied across different consumer groups and positively moderated the relationship between customer certainty and perceived value/purchase intentions. Finally, the results show positive main effects of communication strategies on customer certainty and U-shaped moderation effects on the relationship between the fit and customer certainty. The study also found a positive moderation of individual self-construal on the main effects of both types of communication strategies. Theoretical and managerial implications are offered along with directions for future research.

To address the growing concerns over national energy security and climate change, significant amount of efforts have been made for developing sustainable biofuels and chemicals from renewable lignocellulosic biomass. Gluconic acid and xylonic acid are two important chemicals in food and pharmaceutical industries, which can be produced through fermentation by the microorganism Gluonobacter oxydans. The value-added chemicals production (such as gluconic acid and xylonic acid) from lignocellulosic biomass can generate extra revenue in the forest biorefinery process, which has the potential to significantly improve the viability of biofuels production from biomass. In this study, we first investigated the gluconic acid and xylonic acid fermentation on glucose and xylose respectively without pH control. A nearly 100% conversion of glucose was obtained resulting in a gluconic acid production yield of 100%. However, for xylonic acid fermentation, only 61% conversion of xylose was reached after 48 h with a xylonic acid production yield of 57%. The low conversion yield of xylose probably was caused by the quick pH dropping and pH-sensitive enzymes. Subsequently, the effects of pH control (addition of CaCO3, NaOAc buffering, NaOH neutralization) on gluconic acid and xylonic acid fermentation were further studied. Higher pH (>5.5) resulted in further oxidation of gluconic acid to 2-keto gluconic acid (2KGA) and 5-ketogluconic acid (5KGA) in the gluconic acid fermentation on glucose. With the addition of CaCO3 at 6 g/L, xylose was completely converted into xylonic acid in the 48 h fermentation by G. oxydans. iii Finally, we studied the gluconic acid and xylonic acid fermentation on pretreated woody biomass. Sweetgum (wood chips) was first pretreated with 50% ethanol and 1% H2SO4 at 170 ⁰C for 1 h. The pretreated substrate was washed and collected for gluconic acid production through SHF (separated hydrolysis and fermentation) and SSF (simultaneous saccharification and fermentation) with 2.5, 5.0 and 10.0 FPU/g enzyme loading. In SHF process, the hydrolyzed glucose was quickly converted to gluconic acid within 10 h, and considerable amount of KGA (up to 20 g/L) was also produced with the further extension of fermentation to 48 h. In the SSF process, the hydrolyzed glucose was accumulated during the fermentation, which indicated the fermentation conditions (pH 4.8 and 37 ºC) in the SSF process was not suitable for gluconic production by G. oxydans. In conclusion, we believe that pH plays a very important role in gluconic acid and xylonic acid fermentation by G. oxydans. For gluconic acid fermentation, relatively high pH (>5.5) results in the accumulation of ketogluconic acid. For xylonic acid production, pH should be governed under neutral condition.

Controllable liquid crystal alignment with the assistance of reactive monomers is realized by the Surface Localized Polymer Alignment (SLPA) system. The SLPA system allows fully controllable liquid crystal pretilt angles, which could open new types of liquid crystal device fabrication techniques.The SLPA method not only allows a fully controllable pretilt angle, but also allows different pretilt angles to be set in different areas. More specifically, the concept of this type of alignment is to polymerize a low concentration of reactive mesogens in a liquid crystal cell while a voltage is applied. In the SLPA system, the polymer layer is designed to be only present on the cell surface. Since most of monomers are polymerized on the cell surface and form a rigid polymer layer which is preferably less than a wavelength of light in thickness, the light scattering issue can be solved.

It is still an open problem whether smooth solutions to the 3D Navier-Stokes equations lose regularity in finite time. But it is known that if the enstrophy ( w 22 ) remains finite, the solution is regular. The growth rate of the enstrophy can be estimated from the Navier-Stokes equations by Sobolev inequalities. In general form, dw 22/dt≤c w2 2a , where c is a constant. In 2D the exponent alpha is 2 and leads to regularity. However, alpha = 3 in 3D, which yields only finite-time regularity of the solutions. In these estimates, incompressibility is not used. We formulate the maximal enstrophy growth rate as a variational problem and include incompressibility as a constraint. The variational problem is solved numerically by a gradient-flow type algorithm. Our results show that alpha = 1.78 for small enstrophies and alpha = 3 as enstrophy gets larger. Thus the Sobolev bounds are actually realizable even with incompressibility constraint.