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This thesis studied the influence of moisture content on the dynamic estimation of stiffness in wood of Pinus radiata D. Don. This is an important non-destructive measure for estimation of stiffness in standing trees, logs and lumber. Moisture content affects both acoustic velocity and density in the fundamental equation of dynamic MOE (DMOE = V²ρ, where V = acoustic velocity and ρ = density). Investigation included measurements with boards in the laboratory considering moisture contents below and above FSP as well as temperatures below and above 0°C. This also included field measurements of trees in contrasting climate sites and over different seasons including a long drought. Methods for measuring green density and moisture content and the patterns of variation of these parameters were also investigated. A secondary component of this thesis explored the wood quality and some mechanisms of tree response to water stress in two contrasting sites in terms or rainfall and water deficits in a region of Australia. The large increases in DMOE for frozen wood above the FSP (4.5 to 6 GPa) will limit the use of DMOE for grading logs in regions with freezing winters. Results from the experiment remeasuring young trees and the upper range of moisture content and temperatures above 0°C from the experiment with boards showed small to moderate variation in DMOE (0.1 to 1 GPa) which calls for further investigation on analytical procedures for adjustment of DMOE. Such procedures should consider that variations in acoustic velocity and density with changes in moisture content are not proportional and that there are counteracting effects between the two parameters. It remains to be investigated whether the typical variation (under normal climate conditions) in sapwood green density observed in our experiments has some implications for the use of DMOE. On the other hand, it is anticipated that the large differences along the stem and among stands in whole-section green density may bias DMOE measurements in logs for resource assessment. This also needs to be investigated. A comparison between acoustic velocity alone and DMOE for resource assessment under different scenarios is recommended. The study in two contrasting climate sites (high-altitude vs. warm-dry) in the Hume region of Forests NSW, Australia, including young (10-11 years) and mature trees (34 36 years) of radiata pine showed distinctive short and long-term responses of trees to cope with the water-limiting environment. In response to long-term water deficits the warm-dry site developed heartwood and thus reduced sapwood earlier and at faster rates than the high-altitude site. The onset of heartwood formation seemed to be triggered by some site threshold for water use as broadly indicated by the sapwood area/ha. The latter was consistently lower for the warm-dry site across the different stands. The warm-dry site also showed increased short-term responses to water stress and these were interpreted as seasonal mechanisms of the trees to cope with the limiting environment. The trees compensated for the lower available moisture and higher transpiration rates by lowering their saturation and disrupting water conduction at some points (cavitation). The inverse trends of cavitation spots and cavitation bands with height in the stem suggested the trees have different strategies to sacrifice conducting xylem depending on the position on the stem. Finally, it is suggested that saturation tended to fall to critical 'safe' levels as a result of water stress and this varied depending on age, site, and position in the stem. Significant decreases in DMOE and basic density were observed for the warm-dry site and were attributed to lower proportions of latewood due to lower rainfall for that site during the period of latewood formation. These showed no obvious association with any of the long-term water-stress traits (sapwood percentage and number of heartwood rings).

This thesis describes the design of an instrument for the protection of personnel carrying out live line bare hand maintenance of power transmission circuits. This instrument monitors the leakage current along equipment to ground and sounds an alarm when preset thresholds are exceeded. The leakage current monitor is microprocessor controlled, resulting in both flexible and user friendly operation. The prototype constructed, has been tested and found to perform very well.

Productivity and safety concerns of traditional cable harvesting systems have been the key drivers for increasing levels of mechanisation in New Zealand. The use of grapples in cable yarding could eliminate the need for motor-manual tree fallers and breaker-outs in most situations. A comparative time study was carried out on two mechanised cable harvesting systems utilising grapple carriages in an attempt to better understand the benefits and limitations of each system in different harvest settings. These systems include the Mechanical system which involved a swing yarder operating a mechanical grapple carriage and the Motorised system, which used a tower yarder with a motorised grapple carriage. The Mechanical system took less time to accumulate felled trees but took longer to unhook trees on the landing than the Motorised system. The Mechanical system had a shorter cycle time (2.07 minutes) than the Motorised system (2.32 minutes) and extracted 1.3 tonnes more than the Motorised system per cycle. The Motorised system had shorter cycle times when in horizontal haul distances of less than 90 metres, but had the longest times when the distance exceeded this. Utilisation rates were similar between the two systems, although the main difference in delays between the two systems was the use of surgepiles on the landing by the Motorised system. Both systems were effective, although on average the Mechanical system was more productive, with a productivity of 45 t/SMH, compared to 40 t/SMH for the Motorised system. The Mechanical system was the most productive when extracting mechanically felled and pre-bunched or trees while the Motorised system was the most productive when extracting motor-manually felled trees. Pre-bunching with an excavator was a more cost effective method than handing stems directly to the grapple carriage. Further research of the Mechanical system under more adverse conditions would allow a better overall comparison.

In recent years, semiconductor quantum dots (QDs) have arisen as a new class of fluorescent probes that possess unique optical and electronic properties well-suited for single-molecule imaging of dynamic live cell processes. Nonetheless, the large size of conventional QD-ligand constructs has precluded their widespread use in single-molecule studies, especially on cell interiors. A typical QD-ligand construct can range upwards of 35 nm in diameter, well exceeding the size threshold for cytosolic diffusion and posing steric hindrance to binding cell receptors. The objective of this research is to develop tagging strategies that allow QD-ligand conjugates to specifically bind their target proteins while maintaining a small overall construct size. To achieve this objective, we utilize the HaloTag protein (HTP) available from Promega Corporation, which reacts readily with a HaloTag ligand (HTL) to form a covalent bond. When HaloTag ligands are conjugated to size-minimized multidentate polymer coated QDs, compact QD-ligand constructs less than 15 nm in diameter can be produced. These quantum dot-HaloTag ligand (QD-HTL) conjugates can then be used to covalently bind and track cellular receptors genetically fused to the HaloTag protein. In this study, size-minimized quantum dot-HaloTag ligand conjugates are synthesized and evaluated for their ability to bind specifically to purified and cellular HTP. The effect of QD-HTL surface modifications on different types of specific and nonspecific cellular binding are systematically investigated. Finally, these QD-HTL conjugates are utilized for single-molecule imaging of dynamic live cell processes. Our results show that size-minimized QD-HTLs exhibit great promise as novel imaging probes for live cell imaging, allowing researchers to visualize cellular protein dynamics in remarkable detail.

Der Begriff „live“, wie er in Zusammenhang mit audiovisuellen Arrangements verwendet wird, bezieht sich weniger auf menschliche Verhältnisse, sondern beschreibt eine spezifische zeitliche Dimension medientechnologischer Übertragung. Die Frage „What is live“ wird daher eher unter medienarchäologischen und epistemologischen Aspekten untersucht. Worauf beruht die Gegenwarts-generierende Macht von Medien? Neo-kybernetisch gesehen bewegt sich die Untersuchung also von den Medien inhärenten performativen und dramaturgischen Fragen weg. Elektrisch generierte Kommunikation – in der angelsächsischen Medienwissenschaft gern „Hertzean media“ genannt – zeichnet sich gerade dadurch aus, Gegenwart (also „liveness“) herzustellen. Auf der kognitiven Ebene herrscht jedoch beim Menschen weiterhin das Bewusstsein von der Distanz vor, die symbolischen Codes wie Texten und Alphabet eignet. Daraus entsteht eine affektiv-kognitive Dissonanz.

Theileria parva is a complex protozoan parasite causing East Coast fever in Eastern and Central Africa. Vaccination using live parasites is an effective control measure and has been used in Zambia based on locally isolated and introduced T. parva stocks. Diversity among T. parva populations was investigated in parasites from two Zambian provinces with different disease epidemiologies and control histories. Isolates from the pre-vaccination era, local and exotic stocks used for vaccination, and one recent field isolate were cloned and passaged in vitro to study genomic stability over time. The results of the data from three genome-wide probes indicate a marked homogeneity and stability among the Zambian isolates in contrast to East African isolates. Results from Southern blot profiles and the polymorphic immunodominant molecule (PIM) sequence analysis suggest a common origin for the Zambian isolates from the pre-vaccination era, except for one isolate (Zam5) from Southern Province. This isolate showed characteristics suggesting a buffalo origin. Assays for genotype characterisation were developed using five allelic markers. Multilocus characterisation revealed identical profiles in a recent Zambian isolate from Southern Province and two components of an exotic cocktail vaccine, indicating the escape of one of the vaccine stocks in the field. Characterisation of T. parva field populations by RFLP-PCR assays after immunisation revealed the presence of dominant genotypes from those that had been used for vaccination. Circumstantial evidence for the involvement of one of the exotic vaccine parasites in epidemics in Southern Province is presented and a hypothesis formulated for the rapid spread of this genotype. Analysis of the characterisation data suggested the existence of two groups of T. parva parasites of different origin. The classic T. parva group, characterised by a dimorphism of the p150, p104 and p32 loci and the absence of a p67 insert and a buffalo-derived group which showed a polymorphism of p150, p104 and p32 and the presence of a p67 insert. There is evidence that recombination occurs, resulting in parasites that have characteristics of both groups. The relevance of these recombinant parasites in the epidemiology of the disease seems low. Characterisation of larger samples from areas of regular buffalo-cattle contact is necessary to clarify this. Sequence analysis of the most discriminative locus (PIM) was undertaken and gene conversion could be the main mechanism generating diversity. A more appropriate nomenclature for T. parva is proposed based on the growing evidence of molecular differences among isolates and stocks.

The recent rapid increase in the number of Korean children who return to Korea after time spent abroad studying English raises concerns about their follow-up education and their readjustment into the Korean education system. The number of returnee children also raises concerns about how Korean teachers teach these children. This study was grounded in my realization that my experiential knowledge of learning English influenced my teaching of returnee children. Through this study, I came to understand the ways teachers’ personal practical knowledge of English is shaped through many different experiences in many different contexts in which they are, and were, situated. Teachers’ personal practical knowledge is expressed in their classroom practices. Knowledge and context are linked by the narrative concept of stories to live by (Connelly & Clandinin, 1999). The research was a narrative inquiry into three Korean teachers’ personal practical knowledge as it was expressed in their teaching practices, as it shaped their stories to live by and as it was shifted on their professional knowledge landscapes when they taught returnee children. As a result of the study, four key considerations emerged. One, each teacher’s personal practical knowledge as expressed in teaching returnee children was shaped by his experiences of learning English. Two, shifting teachers’ ‘stories to live by’ depended on their professional knowledge landscapes. Three, teachers held different understandings about curriculum making. Four, teachers held different views about returnees’ readjustment into the Korean schools. Drawing upon a concept of ‘curriculum of lives’ (Clandinin & Connelly, 1992), the key considerations from the study give important implications about in-service teacher education in terms of curriculum making for returnee children. The study suggests the importance of providing in-service teachers with an opportunity to think about a narrative perspective about curriculum making in order to suggest new possibilities for teachers, returnee children, and their parents.

Despite the controversy over environmental sustainability, salmon aquaculture in British Columbia is economically important for many coastal communities and is reported as being the largest agricultural export product for the province. This thesis examined the welfare status of commercially produced Atlantic salmon smolts during transport from freshwater farms to the saltwater net pens using physiology and behaviour to assess transport stress. Smolts were transported first by truck from the freshwater farm to the dock, and then in the flow-through cargo holds of a live-haul vessel to the saltwater net pens. Fish and water were sampled before and after truck transport, and several times aboard the vessel. Assessment of stress was based on measurement of plasma cortisol, glucose, lactate, potassium, sodium and chloride concentrations, as well as behavioural observations made on underwater video footage. Seven transports of fish originating from two different hatcheries were sampled; one was a land-based tank hatchery that required a 30-min drive to the dock, and the other a lake net pen facility that was 90 min to the dock. Analysis of plasma constituents supported previous studies that recovery from the stress accumulated during loading and truck transport can be quite rapid in a live-haul vessel. Underwater video footage, recorded at the freshwater farms and in the cargo holds of the Sterling Carrier, also suggested recovery onboard in that for the most part, behaviour onboard was similar to behaviour at the freshwater farms. There were some significant differences between fish from the two types of hatcheries, particularly in the original hatchery conditions and in their behavioural responses to transport conditions; however, post-transport growth and mortality rates reported by the saltwater farms showed no significant difference. Although fish were subjected to moderately stressful conditions during part of the process, smolt transport as currently carried out by our industry partners reflects good husbandry practices and fish welfare.

Using the generative processes developed over two stages of creative development and the performance of The Physics Project at the Loft at the Creative Industries Precinct at the Queensland University of Technology (QUT) from 5th – 8th April 2006 as a case study, this exegesis considers how the principles of contemporary physics can be reframed as aesthetic principles in the creation of contemporary performance. The Physics Project is an original performance work that melds live performance, video and web-casting and overlaps an exploration of personal identity with the physics of space, time, light and complementarity. It considers the acts of translation between the language of physics and the language of contemporary performance that occur via process and form. This exegesis also examines the devices in contemporary performance making and contemporary performance that extend the reach of the performance, including the integration of the live and the mediated and the use of metanarratives.