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This thesis provides a geographical analysis of the response of the Canadian nation-state to human smuggling. I contend that nation-states must be examined in relation to transnational migration and theorized as diverse sets of embodied relationships. As a case study, I conducted an ethnography of the institutional response to the arrival of four boats carrying migrants smuggled from Fujian, China to British Columbia in 1999. I studied the daily work of border enforcement done by civil servants in the federal bureaucracy of Citizenship and Immigration Canada (CIC), as well as the roles played by other institutions in the response to the boats. This "ethnography of the state" led me to theorize the nation-state geographically as a network of employees that interact with a variety of institutions in order to enact immigration policy. I also interviewed employees of other institutions involved in the response to human smuggling, including provincial employees, immigration lawyers, service providers, suprastate organizations, refugee advocates, and media workers. The thesis explores crossinstitutional collaboration among them and the resulting decision-making environment in which civil servants design and implement policy. Civil servants practice enforcement according to how and where they "see" human smuggling. My conceptual understanding of state practices relates to these efforts to order transnational migration. Diverse institutional actors negotiate smuggling at a variety of scales. Power relations are visible through discussions of smuggling at some scales, but obscured at others. I "jump scale" through embodiment in order to understand the micro-geographies of the response. This shift in the scale of analysis of the nation-state uncovers different relationships, interests, and negotiations in which state practices are embedded. This approach to geographies of the nation-state considers the time-space relations across which state practices take place, the everyday enactment of policy, the categorization of migrants, and the constitution of borders through governance. I argue that such an approach is key to understanding the relationship between nation-states and smuggled migrants. The findings suggest a re-spatialization of enforcement through which nation-states increasingly practice interception abroad and design stateless: spaces, and in so doing, reconstitute international borders. / Arts, Faculty of / Geography, Department of / Graduate

This study sheds light on the role of social networks in entrepreneurship in the e- commerce sector in contemporary China. It examines the usefulness of network ties for entrepreneurship, specifically the capacity of network ties to provide information, advice, resources and emotional support during the creation and growth stages of small and medium-sized e-commerce businesses. Using data from semi-structured interviews with 30 private entrepreneurs in Anhui province in China, I first identified the roles played by family, friendship, business and political ties in e-commerce entrepreneurship, as well as their respective advantages and disadvantages. I then examined the changes in the roles of different network ties in e-commerce entrepreneurship as businesses move from the firm creation stage to the firm growth stage. Following this, I compared online and offline social networks to understand the similarities and differences in their respective effects on e-commerce entrepreneurship. My study presents three main research findings. The first research finding is about the role of strong ties in entrepreneurship. Specifically, I found that strong ties, such as family and friendship ties, are especially important for Chinese entrepreneurs to acquire scarce resources, especially financial and human resources, and for providing emotional support to cope with the highs and lows of running a business. However, there are also disadvantages brought by these strong network ties, including 'over- embeddedness' and conflict with family members and between friends. In addition, although strong ties are important for entrepreneurs to acquire scarce resources during the firm creation stage, its role might diminish as the firm grows. The second research finding is about the role of weak ties in entrepreneurship. In contrast with strong ties, weak ties, such as online business ties, are quite important for e-businesses to connect with a diverse range of people to get a diverse range of resources, advice and information, and emotional support. With the help of the Internet, entrepreneurs can easily develop these weak ties. Last but not least, the third research finding is about the role of political ties. To be specific, under the marketization trend in the e- commerce sector, the role of political ties in entrepreneurship is decreasing. Political ties are not necessary during the firm creation stage, but they might become useful in solving problems that arise in the growth stage, such as tax issues. There are three contributions of the study on the relationship between social networks and entrepreneurship. Firstly, the role of strong ties is found to have advantages and limitations in providing resources, advice and information and emotional support in entrepreneurship in the e-commerce sector, like in other sectors studied by previous research. Secondly, weak ties play an important role in connecting with a diverse number of acquaintances in providing them, especially as firms grow. In e-commerce sector, the Internet helps entrepreneurs to develop these weak ties. Last but not least, the macro-social conditions in an economy and in a specific sector should be considered when studying the role of network ties in entrepreneurship.

Infectious diseases are the major cause of human death worldwide and the need for new generations of anti-infective agents to overcome the drug resistant urgently needs to be tackled. Plant natural products are potential sources of novel antimicrobial compounds. In this study, an investigation into the antimicrobial lead compounds from Michelia figo, Macleaya cordata and Ardisia gigantifolia in Lingnan region is presented. The prevention of dental diseases is targeted at the control of dental biofilm. Streptococcus mutans and S. sobrinus are the leading bacterial strains in the formation of dental biofilm. Extracts of Michellia figo and Macleaya cordata displayed antimicrobial potential in our screening assays. Bioassay-guided isolation of M. figo revealed the presence of artabotryside B and acteoside which were isolated for the first time from this plant. Moreover, chelerythrine and sanguinarine, the two alkaloids isolated from Macleaya cordata displayed the ability to prevent the formation of biofilms of S. mutans and S. sobrinus with the MIC50 values in the range of 18.5-34.0 μM. Anti-TB bioassay-guided isolation of the extract of Ardisia gigantifolia led to isolation of two 5-alkylresorcinols, 5-(8Z-heptadecenyl) resorcinol (1) and 5-(8Z-pentadecenyl) resorcinol (2). We further synthesized 15 derivatives based on these two compounds. Resorcinols 1 and 2 exhibited anti-TB activity with MIC values at 34.4 μM and 79.2 μM in MABA assay, respectively, and 91.7 μM and 168.3 μM in LORA assay, respectively. Among these derivatives, compound 8 was found to show improved anti-TB activity than its synthetic precursor (2) with MIC values at 42.0 μM in MABA assay and 100.2 μM in LORA assay. Chelerythrine and sanguinarine are the representative and the major active constituents of M. cordata. Both compounds showed significant fungicidal effects in vitro and significant therapeutic effects on guinea pigs of dermatophytosis. Mechanism study for the antifungal efficacy showed that chelerythrine and sanguinarine were potent inhibitors of ergosterol bio-synthesis by reducing the amount of ergosterol without affecting the synthesis of 1,3-β-glucan. In summary, these results highlight the promising antimicrobial activity of chelerythrine, sanguinarine and alkylresorcinols from the medicinal plants in Lingnan region. The active compounds may be regarded as new hits for further study as novel classes of antimicrobial agents for the treatment of infectious diseases.

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