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The purpose of this thesis is to probe the nature of Luke's soteriology by focusing on Luke’s geographical (spatial-temporal) perspective within which the narrative world of Luke-Acts moves. In this thesis, by presenting space-time as intertwined aspects of the same event or reality, I have proposed that we rethink Luke's space-time as a dynamic event in motion. Within this framework, I have proposed that Luke's notion of salvation should be understood not as a static system for containing motion or a fixed framework for defining action, but as a dynamic event in motion, becoming, and flowing, which creates a new salvific space-time (i.e. the kingdom of God) in-between, among, around, and beyond regions and persons. Thus, 1 have proposed that we think of salvation in terms of the nomadic movements of flows that unfold the multiple layers (multiplicity) of release from various fabrics of captivity and oppression - i.e., release from sins and various forms of physical-spiritual sicknesses, stigmas, and debts. Thus we should rethink salvation in the following ways. (1) Not in terms of a dichotomy between physical and spiritual, but as both physical spiritual: both conditions applying to the same saving event. (2) Not as hierarchical or singular, but as heterogeneous and multiple. (3) Not as static moments, but as something flowing, being-toward, and in motion, showing that salvation and its nomadic event of flows is pictured as being in a constant state of movement, signifying an endless qualitative change in type and kind. This means salvation is a nomadic event of release and deterritorialization from one sphere to another. It deterritorializes the fixed, binary, and hierarchical system of the Jerusalem temple, creates the heterogeneous and relational space of God, and establishes multiple access points to the dynamic network (the kingdom) of God.

In this dissertation, based on conservation of resources (COR) theory, I aim to provide insight into the dynamic nature of work-family conflict among working mothers by exploring trajectories of work-family conflict in terms of work interference with family (WIF) and family interference with work (FIW) and the extent to which increases in job and family satisfaction buffer the effects of work-family conflict over time. The two commonly-used perspectives in the work-family literature are the matching-domain perspective (i.e., that the primary effects of conflict lie in the domain where the conflict emerged) and the cross-domain perspective (i.e., conflict emerging from one domain causes problems in another). According to COR scholars, it is important to view COR theory in context and to explore resource boundary conditions. I contribute to the conceptualization of resources by investigating the matching- and cross-domain perspectives with regard to resources and where such resources stem from. Specifically, I examine whether job and family satisfaction work better as buffer resources when they come from the same domain as the conflict (i.e., the matching-domain perspective) or when they come from another domain (i.e., the cross-domain perspective). Using an archival data set with a panel longitudinal design in which data were collected from 261 working mothers in dual-earner couples in South Korea at four time points over a period of six years, this dissertation shows the stability of WIF and FIW over time and generally supports the hypothesis that increases in job satisfaction buffer the effect of WIF on subsequent WIF; however, increases in job satisfaction did not buffer the effect of FIW on subsequent of FIW. Increases in family satisfaction also did not buffer the effect of WIF on subsequent WIF or the effect of FIW on subsequent FIW. Although not hypothesized, I found that family satisfaction amplified the effect of WIF on subsequent FIW. These findings suggest that although both job and family satisfaction have been viewed as positive constructs, family satisfaction may not always act as a resource but can also be a hindrance when it comes to working mothers managing work-family conflict.

Biosynthetic studies of natural products are essential to the discovery and development of new drugs, because by understanding biosynthetic pathways and the enzymes that characterize them, new pathways can be engineered for the production of new compounds with improved clinical properties. Aminoglycosides have traditionally been used as important antibiotics, but resistance against aminoglycosides is well known. This has resulted in a need to better understand the biosynthesis of aminoglycosides. Besides the practical value, the discovery of new enzymes with unprecedented functions in the biosynthesis of aminoglycosides can expand our knowledge and advance our understanding of enzyme catalysis. The work described in this dissertation focuses on the in vitro characterization of two radical S-adenosyl-L-methionine (SAM) enzymes in the biosynthesis of aminoglycosides. First, GenK is a cobalamin (Cbl)-dependent radical SAM enzyme that is responsible for catalyzing the methylation of gentamicin X₂ to produce G418. In vitro assays of purified and reconstituted GenK from Micromonospora echinospora showed that this enzyme is a radical SAM enzyme with one [4Fe-4S] cluster. Assays of GenK with SAM, gentamicin X₂ and Cbl confirmed that the methylation reaction occurs at an unactivated carbon during gentamicin biosynthesis. Isotope labeling experiments strongly suggested that SAM is the preliminary methyl donor to cobalamin, followed by secondary transfer from Me-Cbl to gentamicin X₂. It was demonstrated that GenK also accepts alternative aminoglycoside substrates besides gentamicin X₂. Second, three possible mechanisms for the GenK reaction were suggested and tested. Experiments investigating the stoichiometry of the GenK reaction revealed 5'-deoxyadenosine (5'-dAdo), S-adenoxylhomocysteine (SAH), and G418 were produced in equal proportion and one-to-one with each methylation reaction catalyzed by GenK. The experiment with labeled substrates indicated that the 6'-pro-R-hydrogen atom of gentamicin X₂ is abstracted by 5'-dAdo• and that methylation occurs with retention of configuration at C6'. Several substrate derivatives were synthesized to investigate the manner of methyl transfer from cobalamin to the substrate. Finally, the in vitro characterization of AprD4 and AprD3 in the biosynthesis of C3'-deoxyaminoglycoside was also conducted. Purified and reconstituted AprD4 from Streptomyces tenebrarius is a radical SAM enzyme, catalyzing homolysis of SAM to 5'-dAdo in the presence of paromamine to produce 4-oxolividamine. AprD3 from the same strain is shown to be a dehydrogenase acting as the reductase counterpart to AprD4 to catalyze the reduction of 4-oxolividamine to generate lividamine. The experiments with labeled compounds confirmed the regiochemistry of hydrogen atom abstraction by 5'-dAdo• and the stereochemical course of C3'-deoxygenation of paromamine.

The increasing demands for high-quality multimedia services have challenged the wireless industry to rapidly develop wireless network architecture and technologies. These demands have led wireless service providers to struggle with the current network migration dilemma of how to best deliver high-quality multimedia services. Currently, there are many alternative wireless network technologies, such as TDMA, GSM, GPRS, EDGE, WCDMA, cdma2000, etc. These wireless technology choices require close examination when making strategic decisions involving network evolution.This study assesses the technology options for wireless networks to establish next generation networks (i.e., 3G), based on the real options approach (ROA), and discusses wireless network operators¡¯ technology migration strategies. The goal of this study is to develop a theoretical framework for wireless network operators to support their strategic decision-making process when considering technology choices. The study begins by tracing the evolution of technologies in wireless networks to place them in the proper context, and continues by developing the strategic technology option model (STOM) using ROA as an assessment tool. Finally, STOM is applied to the world and US wireless industries for the formulation of technology migration strategies. Consequently, this study will help wireless network service providers make strategic decisions when upgrading or migrating towards the next generation network architecture by showing the possible network migration paths and their relative value. Through this study, network operators can begin to think in terms of the available network options and to maximize overall gain in networks. Since the migration issues concerning the next generation wireless network architecture and technologies remain the subject of debate, with no substantial implementation in progress now, this study will help the industry to decide where best to focus its efforts and can be expanded for further research.

Diverse biological activities of polyketide natural products are often associated with specific structural motifs, biosynthetically introduced after construction of the polyketide core. Therefore, investigation of such "post-polykektide synthase (PKS)" modifications is important, and the accumulated knowledge on these processes can be applied for combinatorial biosynthesis to generate new polyketide derivatives with enhanced biological activities. In addition to the practical value, a lot of unprecedented chemical mechanisms can be found in the enzymes involved therein, which will significantly advance our understanding of enzyme catalysis. The works described in this dissertation focus on elucidating a number of post-PKS modifications involved in the biosynthesis of an insecticidal polyketide, spinosyn A, in Saccharopolyspora spinosa. First, three methyltransferases, SpnH, SpnI, and SpnK, responsible for the modification of the rhamnose moiety, have been investigated to verify their functions and to study how they are coordinated to achieve the desired level of methylation of rhamnose. In vitro assays using purified enzymes not only established that SpnH, SpnI, and SpnK are the respective rhamnose 4ʹ-, 2ʹ-, and 3ʹ-O-methyltransferase, but also validated their roles in the permethylation process of spinosyn A. Investigation of the order of the methylation events revealed that only one route catalyzed by SpnI, SpnK, and SpnH in sequence is productive for the permethylation of the rhamnose moiety, which is likely achieved by the proper control of the expression levels of the methyltransferase genes involved in vivo. The key structural feature of spinosyn A is the presence of the unique tetracyclic architecture likely derived from the monocyclic PKS product. To elucidate this "cross-bridging" process, which had been hypothesized to involve four enzymes, SpnF, SpnJ, SpnL, and SpnM, the presumed polyketide substrate was chemically synthesized using Julia-Kocienski olefination, Stille cross-coupling, and Yamaguchi macrolactonization as key reactions. Incubation of the synthesized substrate with SpnJ produced a new product where the 15-OH group of the substrate is oxidized to the ketone. Next, it was demonstrated that incubation of this ketone intermediate with SpnM produces a tricyclic compound, via a transient monocyclic intermediate with high degree of unsaturation. Whereas it was initially thought that SpnM catalyzes both dehydration and [4+2] cycloaddition in sequence, detailed kinetic analysis revealed that SpnM is only responsible for the dehydration step, and the [4+2] cycloaddition step is indeed catalyzed by SpnF. Finally, successful conversion of the tricyclic intermediate to the tetracyclic core was demonstrated using SpnL. Proposed chemical mechanisms of SpnF and SpnL, Diels-Alder and Rauhut-Currier reactions, respectively, are interesting because enzymes capable of catalyzing these reactions have yet to be characterized in vitro. This work not only establishes the biosynthetic pathway for constructing the spinosyn tetracyclic core, but also epitomizes the significance of the post-PKS modification as a rich source of new enzyme catalysis.