Novel particulate vaccine candidates recombinantly produced by pathogenic and nonpathogenic bacterial hosts : a thesis presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Microbiology at Massey University, Manawatu, New Zealand.

Polyhydroxyalkanoates (PHAs) are biopolyesters synthesized as small spherical cytoplasmic inclusion bodies by a range of bacteria. Recently, PHA beads have been investigated for use as a vaccine delivery platform by using engineered heterologous production hosts that allowed the efficient display of vaccine candidate antigens on the beads surface and were found to greatly improve immunogenicity of the displayed antigens. However, like other subunit vaccines, these antigen-displaying (vaccine) PHA beads only provide a limited repertoire of antigens. In this thesis we investigate the idea of directly utilizing the disease causative pathogen or model organism to produce vaccine PHA beads with a large antigenic repertoire. These beads are hypothesized to have the potential to induce greater protective immunity compared to production of the same PHA bead in a heterologous production host. This concept was exemplified with Pseudomonas aeruginosa and Mycobacterium tuberculosis as model human pathogens. For P. aeruginosa we describe the engineering of this bacterium to promote PHA and Psl (polysaccharide) production. This represents a new mode of functional display for the engineering, production, and validation of a novel OprI/F-AlgE fusion antigen-displayed on PHA beads. For the disease tuberculosis we investigated the use of nonpathogenic M. smegmatis as a model organism for M. tuberculosis. We described the bioengineering, production, and validation of Ag85AESAT- 6 displayed on PHA beads produced in M. smegmatis. Here we showed that both organisms were harnessed to produce custom-made PHA beads for use as particulate subunit vaccines that carried copurifying pathogen-derived proteins as a large antigenic repertoire and the ability of these vaccine PHA beads to generate a protective immune response. This novel bioengineering concept of particulate subunit vaccine production could be applied to a range of pathogens naturally producing PHA inclusions for developing efficacious subunit vaccines for infectious diseases

Cognitive Structure of Social Mobility: Moral Sentiments and Hidden Injuries of Class

Drawing on the mobility accounts of eighty-nine respondents who perceived themselves as socially mobile in post-war Hong Kong, I devise a typology of four biographies – normal, choice, special, and emotional biographies – to examine the cognitive structure of their accounts in order to make sense of moral sentiments of class. Three tentative conclusions are drawn. First, class feelings could be seen as better class markers than self-reported class identity. Second, upward mobility does not simply complicate class feelings but could lead to a distorted class sentiment that justifies rather than challenges class inequality; yet four biographies show a variety of its operation. Third, upward mobility does not necessarily treat previous class injuries; instead, it could bring new class injuries. In sum, social fluidity of a class society does not make class inequality less arbitrary or more just nor does it necessarily render class feelings and moral sentiments of class as irrelevant.Moral Sentiments of Class, Class Injuries, Social Mobility, Biography, Middle Class, Hong Kong

Firms’ Innovative Performance: The Mediating Role of Innovative Collaborations

While existing studies have provided many insightful discussions on the antecedents to innovative collaborations and the benefits of collaborative behavior, few studies have focused on the mediating role of innovative collaborations in enhancing the firm’s technological innovative performance. In this paper, we investigate the mediating role of the firm’s innovative collaborations in the relation between government innovation support and the firm’s product and process innovation intensities. As a mediating factor in the innovation process, innovative collaborations form part of the innovative inputs that contribute to the firm’s product and process innovation intensities. Using arguments derived from the resource-based theory, we found that while receipts of government innovation support help increase the firm’s level of innovative inputs as observed in its collaboration intensity, it is equally important for firms to internalize management practices that encourage maximum leverage of government innovation support for pursuits of innovative collaborations. In a similar vein, while innovative collaborations are necessary for realizing innovative outputs including product and process innovations, it is not a sufficient condition for achieving strong innovative performance. The firm’s internal capabilities as observed in its learning, R&D, resource allocation, manufacturing, marketing, organizing, and strategic planning abilities have a positive influence on the relationship between innovative collaborations and innovative outputs.Innovative Performance; Innovative Collaboration; Firm’s Contextual Factors

Individual attitudes, organizational reward system and patenting performance of R&D scientists and engineers

The interactive process perspective of innovation suggests that the innovation performance of individual R&D scientist or engineers (RSEs) is influenced by a nexus of interaction between individual attributes and organizational characteristics. While numerous empirical studies have investigated the effects of various sets of individual and organizational antecedents on the innovation performance of individuals, few have examined the interaction effects between the two. This paper addresses this gap in the literature by providing empirical evidence on the interactive effects of the attitudes of individual RSEs and the organizational reward system on the patenting performance of these RSEs.Innovative performance; individual attitudes; organizational reward system

Antipersistant Effects in the Dynamics of a Competing Population

We consider a population of agents competing for finite resources using strategies based on two channels of signals. The model is applicable to financial markets, ecosystems and computer networks. We find that the dynamics of the system is determined by the correlation between the two channels. In particular, occasional mismatches of the signals induce a series of transitions among numerous attractors. Surprisingly, in contrast to the effects of noises on dynamical systems normally resulting in a large number of attractors, the number of attractors due to the mismatched signals remains finite. Both simulations and analyses show that this can be explained by the antipersistent nature of the dynamics. Antipersistence refers to the response of the system to a given signal being opposite to that of the signal's previous occurrence, and is a consequence of the competition of the agents to make minority decisions. Thus, it is essential for stabilizing the dynamical systems.Comment: 4 pages, 6 figure

Slot error rate performance of DH-PIM with symbol retransmission for optical wireless links

In this paper we introduce the dual-header pulse interval modulation (DH-PIM) technique employing a simple retransmission coupled with a majority decision detection scheme at the receiver. We analytically investigate the slot error rate (SER) performance and compare results with simulated data for the symbol retransmissions rates of three, four and five, showing a good agreement. We demonstrate that the proposed scheme significantly reduces the SER compared with the standard single symbol transmission system, with retransmission rate of five offering the highest code gain of 5 dB