We have constructed strains of Pseudomonas aeruginosa with mutations in the algC gene, previously shown to encode the enzyme phosphomannomutase. The algC mutants of a serotype O5 strain (PAO1) and a serotype O3 strain (PAC1R) did not express lipopolysaccharide (LPS) O side chains or the A-band (common antigen) polysaccharide. The migration of LPS from the algC mutant strains in Tricine-sodium dodecyl sulfate-polyacrylamide gels was similar to that of LPS from a PAO1 LPS-rough mutant, strain AK1012, and from a PAC1R LPS-rough mutant, PAC605, each previously shown to be deficient in the incorporation of glucose onto the LPS core (K. F. Jarrell and A. M. Kropinski, J. Virol. 40:411-420, 1981, and P. S. N. Rowe and P. M. Meadow, Eur. J. Biochem. 132:329-337, 1983). We show that, as expected, the algC mutant strains had no detectable phosphomannomutase activity and that neither algC strain had detectable phosphoglucomutase (PGM) activity. To confirm that the PGM activity was encoded by the algC gene, we transferred the cloned, intact P. aeruginosa algC gene to a pgm mutant of Escherichia coli and observed complementation of the pgm phenotype. Our finding that the algC gene product has PGM activity and that strains with mutations in this gene produce a truncated LPS core suggests that the synthesis of glucose 1-phosphate is necessary in the biosynthesis of the P. aeruginosa LPS core. The data presented here thus demonstrate that the algC gene is required for the synthesis of a complete LPS core in two strains with different LPS core and O side chain structures.

The roles of outer membrane permeability and Bush group 1 ␤-lactamase activity in determining Enterobacter cloacae susceptibility to either meropenem or imipenem were investigated. A ␤-lactamase-deficient strain was obtained by mutagenesis from a clinical isolate of E. cloacae, and a porin-deficient strain was selected from this mutant with cefoxitin. Both strains were transformed with the plasmid pAA20R, which contained the gene coding for the carbapenem-hydrolyzing CphA ␤-lactamase, and the carbapenem permeability coefficients were measured by the Zimmermann and Rosselet technique (W. Zimmermann and A. Rosselet, Antimicrob. Agents Chemother. 12:368-372, 1977). The permeability coefficient of meropenem was roughly half that of imipenem in the normally permeable strain and almost seven times lower than that of imipenem in the porin-deficient strain. In the porin-deficient strain, the virtual absence of porins caused the MICs of meropenem to increase from 8 to 16 times, while it did not affect the MICs of imipenem. Conversely, the ␤-lactamase affected imipenem but not meropenem activity: meropenem showed a similar activity in the parent strain and in the ␤-lactamase-deficient mutant with both a low-and high-density inoculum, whereas imipenem was 16 times less active against the parent strain when the high-density inoculum was used. It is concluded that outer membrane permeability and stability to group 1 ␤-lactamase have different impacts on the activities of meropenem and imipenem against E. cloacae.

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<p><b>The construction industry is often referred to as being ‘unproductive’, where studies by both BRANZ and MBIE highlight the importance for the industry to adopt new technologies (Building information modelling ((BIM)) to help improve productivity levels. Although BIM implementation can increase productivity levels (through adoption of collaborative work processes), its Implementation is being negatively influenced by restrictive contractual frameworks (referred to as procurement), where projects are being delivered misaligned to the promised deliverable’s.</b></p> <p>The aim of this thesis was therefore to investigate the fragmentation that procurement selection can have on projects implementing BIM (with a primary focus on the New Zealand construction industry). To begin this investigation, literature was investigated where it was found that traditional procurement methods such as design bid build (DBB) and design build (DB) were ‘inadequate forms of procurement for projects implementing BIM processes’ due to their ‘fragmented nature, where all stages of the development of the building (design, construction, and operation) were not well integrated’ (the stages were separated). Due to this separation between project stages the collaboration and sharing of information (the basis of BIM) between consultants and contractors is reduced, ultimately impacting the success BIM can have within a project.</p> <p>Further within the literature review, new forms of innovative procurement were identified, where these new methods have the ability to better support projects implementing BIM due to the basis of the contract being formed on collaborative work processes. With this information sourced on the various procurement methods, an exploratory sequential methodology was developed to explore the selection of procurement within BIM projects’, as well as the success of these projects’ (where success was measured as projects meeting the triple constraint). This information was gathered within a questionnaire, and a case study, where the intent of this two step methodology was to validate questionnaire findings, whilst allowing for a more comprehensive understanding as to why these results were occurring.</p> <p>Results from the questionnaire found that 93% of projects’ were procured via traditional procurement methods, with DBB being the most common method within New Zealand, with a 61% implementation rate. Of all the data collected on projects’ within the questionnaire It was also identified that only 1 project within New Zealand (implementing an innovative procurement method) met all three aspects of the triple constraint. Although the projects’ procured through innovative methods were identified as being the most successful, key findings within this thesis was that innovative procurement methods are not appropriate on all projects within New Zealand, with this due to the small construction project size, and the cost required to set a project up through these methods being unable to be justified.</p> <p>Discussions with industry professionals identified that a redevelopment of traditional procurement methods is required, to allow the methods to support digital processes, and collaboration amongst the design team, with there also being the need for an independent BIM procurement specialist. The role of this specialist would see them work along side the client, to ensure that BIM was effectively procured within the project in question. An education piece is also required to be undertaken, focusing on the client. This is due to the client being the primary selector of the procurement strategy and method, and it believed that clients do not have a sufficient understanding of the influence that this selection can have on project successes.</p>