This thesis describes a series of experiments that were undertaken to extend the limits of output power and wavelength coverage of optically pumped mid-infrared lasers. Initially, two new CW Raman lasers operating at wavelengths of 11.5 and 12.5 pm were developed. Maximum powers of 650 and 150 mW were produced, with pump powers of 11 and 3.3 W, respectively. The effect of the pump offset on the output power was then determined by measuring the efficiency of an NHg laser pumped at frequency offsets of 94 and 274 MHz. In lasers operating in pure NH3, the larger pump offset required a greater pump intensity to reach threshold, but efficiency increased with pump offset. Higher NH3 pressures could be used at larger pump offsets and the improved efficiency was attributed to reduced saturation effects at the higher operating pressures. Experiments carried out with NHg inversion lasers have greatly increased the output powers available at a large number of wavelengths in the 10 to.14 pm range. In a buffered NH3 mixture, the sR(5,0) transition was pumped on resonance. C^llis;o^r^s with either — or Ar buffer gases were effective in thermalizing the rotational populations in the v>2=1 vibrational level and producing gain on a wide range of frequencies. Output powers as large as 3.5 W on a single line and greater than 5 W multi-line were produced, at efficiencies of 20 and 30 % respectively. The number of lasing wavelengths increased substantially, as more than forty ortho-NH3 transitions were observed to lase in a grating-tuned cavity. The optical pumping technique was then used for the first time to produce line-tunable lasing on para-NH3 transitions. The sR(5,l) transition was pumped near resonance and 24 para-transst'lons were observed to lase. In total, lasing was achieved on 65 different transitions in 14NH3, with wavelengths of 10.3 to 13.8 pm. / Thesis / Master of Science (MSc)

"July 2004." / Bibliography: leaves 120-136. / vii, 136 leaves : ill. (some col.), maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigates the effects of soil moisture dynamics on the growth and interactions between invasive annual grasses and native perennial grasses in the mid-north of South Australia. At most sites annual grass abundance was positively correlated with rainfall, soil moisture after rainfall and higher soil productivity. Perennial grass abundance was negatively correlated with annual grass abundance and soil moisture after rainfall, and was weakly positively correlated with percentage summer rainfall, elevation, radiation, gravel and slope. Overall perennial grasses responded little to the environmental variables investigated, but strongly to annual grass abundance, while for annual grasses soil moisture was the driving variable. / Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2004

Thesis (Ph. D.)--University of Hawaii at Manoa, 1995. / Includes bibliographical references (leaves 77-86). / Microfiche. / ix, 86 leaves, bound ill. (some col.) 29 cm

This thesis explores the role of non-classical correlations in bipartite continuous variable quantum systems, and the approach taken is three-fold. We show that given two initially entangled atomic ensembles, it is possible to probabilistically increase the entanglement between them using a beamsplitter-like interaction formed from two quantum non-demolition (QND) interactions with auxiliary polarised light modes. We then develop an elegant method to calculate density matrix elements of non-Gaussian bipartite quantum states and use this to show that the entanglement in a two mode squeezed vacuum can be distilled using QND interactions and non-Gaussian elements. Secondly, we introduce a potential new measure of quantum entanglement in bipartite Gaussian states. This measure has an operational meaning in quantum cryptography and provides an upper bound on the amount of a secret key that can be distilled from a Gaussian probability distribution shared by two conspirators, Alice and Bob, given the presence of an eavesdropper, Eve. Finally, we go beyond the realm of quantum entanglement to explore other non-classical correlations in continuous variable systems. We provide solutions for a number of these measures on two mode Gaussian states and introduce the Gaussian Ameliorated Measurement Induced Disturbance (GAMID). The interplay between these different measures and quantum entanglement is examined. We then attempt to take small steps into the non-Gaussian regime by computing these non-classicality measures on the three-parameter continuous variable Werner states.

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Previous research has found that hand preference can be detected reliably in infants as young as 6 months of age through the use of reach-grasp tasks. While many studies have targeted their efforts at discerning hand preference in infants younger than 12-months of age, a lack of knowledge about hand preference during the ages of 1-2 years remain. The aim of the present study was to investigate whether 12-month-old infants demonstrate a clear hand use preference during unimanual reaching and grasping. Participants consisted of 54 healthy, full term 12-month-old infants (+2/-2 weeks). Goal objects were placed at a reachable distance, in front of the infants and randomly allocated to either left, midline or right positions. Infant hand choices and the success of each grasp were coded offline from video recordings made of the reach-grasp sessions and an overall lateralisation index (LI) was calculated later for each infant. The results demonstrated that the 12-month-old infants were generally right-preferred. Additionally, almost double the frequency of grasps were accounted for by right hand grasps. Further, a significant right hand preference was found when children reached across the midline to grasp objects. The findings imply that hand preference may be readily observed in the prehension activities of 12-month-old infants, and particularly prominent when reaching across the midline.

Background: Previous research has demonstrated that chronic stress negatively impacts cognition and overall health. Perseverative cognitions such as worry can hold the physiological response of a stressor in the body (Brosschot, Gerin, & Thayer, 2006). The current study consists of two components: 1) a conceptual replication examining whether worry mediates the effect of stress on somatic health and stress and 2) extension of the model with cognition as the outcome. Methods: This study used data from the second wave of the Midlife in the United States data collection: Project 1 (cross-sectional), Project 2 (daily diary), and Project 3 (cognition). Doing so approximated the time-series requirement of a mediation model and enabled access to the variables of interest. Mediation models were run via PROCESS software with covariates adjusted for at each path. Results: Controlling for age, gender, education, household income, and chronic health conditions, the mediation models revealed mediation of the effect of stress severity on somatic health by worry frequency, duration, and self-identification. Conclusions: Worry may be the process through which the physiological response to stress is prolonged thereby increasing the prevalence of effects on somatic health and cognition. By understanding the nuances of how stress impacts somatic health and cognition, prevention and intervention strategies can be implemented to reduce potential long-term outcomes. / Graduate

In this thesis, I present results that broadly fall into two themes. The first involves understanding active tectonic and magmatic processes at mid-ocean ridges. The second involves using small stress changes due to the tides to probe earthquake processes at mid-ocean ridges. The four main results of my thesis are as follow: (1) The spatiotemporal evolution of an eruption at a fast-spreading mid-ocean ridge, the East Pacific Rise, is now characterized and understood to be mainly controlled by the buildup of tectonic stress to a critical level rather than magma overpressure. (2) Microearthquakes at the East Pacific Rise are found to be strongly modulated by tides in the years before an eruption but not immediately after the eruption, suggesting the potential utility of tidal triggering strength for eruption forecasting. (3) Earthquake size-frequency distribution, often quantified using the b value, is shown to vary systematically with tidal stresses which lends support to the use of earthquake b value as an in-situ stressmeter. (4) The 2015 Axial Seamount eruption is revealed to be preceded by variable rates of melt influx into the shallow reservoir, highlighting the short-timescale variability of magmatic systems as they are primed for an eruption.

Student Number : 0213053E MSc research report - School of Electrical and Information Engineering - Faculty of Engineering and the Built Environment / One of the risks that have a great impact on society is military con- °ict. Militarised Interstate Dispute (MID) is de¯ned as an outcome of interstate interactions which result in either peace or con°ict. E®ective prediction of the possibility of con°ict between states is a good decision support tool. Neural networks (NNs) have been implemented to predict militarised interstate disputes before Marwala and Lagazio [2004]. Sup- port Vector Machines (SVMs) have proven to be very good prediction techniques in many other real world problems Chen and Odobez [2002]; Pires and Marwala [2004]. In this research we introduce SVMs to predict MID. The results found show that SVM is better in predicting con°ict cases (true positives) without e®ectively reducing the number of correctly classi¯ed peace (true negatives) than NN. A sensitivity analysis for the in°uence of the dyadic (explanatory) variables shows that NN gives more consistent and easy to interpret results than SVM. Further investigation is required with regards to the sensitivity analysis of SVM.

In this dissertation, I use seismic imaging techniques to constrain the physical state of the upper mantle beneath regions of young oceanic lithosphere. Mantle convection is investigated beneath the Galápagos Archipelago and then beneath the Juan de Fuca (JdF) plate, with a focus on the JdF and Gorda Ridges before turning to the off-axis asthenosphere. In the Galápagos Archipelago, S-to-p receiver functions reveal a discontinuity in seismic velocity that is attributed to the dehydration of the upper mantle. The depth at which dehydration occurs is shown to be consistent with prior constraints on mantle temperature. A comparison between results from receiver functions, seismic tomography and petrology shows that mantle upwelling and melt generation occur shallower than the depth of the discontinuity, despite the expectation of high viscosities in the dehydrated layer. Beneath the JdF and Gorda Ridge, low Vs anomalies are too large to be explained by the cooling of the lithosphere and are attributed to partial melt. The asymmetry, large Vs gradients, and sinuosity of the anomalies beneath the JdF Ridge are consistent with models of buoyancy-driven upwelling. However, deformation zone processes appear to dominate mantle flow over seafloor spreading beneath the Explorer and Gorda diffuse plate boundaries. Finally, S-to-p receiver functions reveal a seismic discontinuity beneath the JdF plate that can only be attributed to seismic anisotropy. Synthesis of the receiver function results with prior SKS splitting results requires heterogeneous anisotropy between the crust and the discontinuity. Models of anisotropy feature increasing anisotropy before the decrease at the discontinuity, but well below the base of the lithosphere, and a clockwise rotation of the fast direction with increasing depth. In these results and even in the SKS splitting results, additional driving mechanisms for mantle flow such as density or pressure anomalies are required.