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This thesis examines Liu Cixin's Diqiu Wangshi (The Remembrance of Earth's Past), a Chinese science fiction trilogy whose translation is unprecedently popular in the Western world. In his interviews and critical writings, Liu Cixin often explains that he is predominantly influenced by modern and contemporary Anglophone authors, including George Orwell, Arthur C. Clarke and Aldous Huxley, among others. By considering Liu's trilogy in view of such influences, this thesis breaks down the aesthetic and thematic components of Diqiu Wangshi, these being scientism, humanism, historicism and utopianism. It also considers the influence of the Chinese author Wang Meng's youth fiction Qingchun Wansui and how its idealism helps to shape the aesthetic and moral character of Liu's work. The purpose of this analysis is to account for the originality of Diqiu Wangshi, arguing that its ingenuity is found in its conscious engagement with translated fiction rather than in the literature of Chinese science fiction. The dissertation more generally aims at exploring how contemporary Chinese writers of the post-Mao period are clearly more influenced by western fiction, translated and untranslated, and universal thematic concerns than current critical approaches seem to suggest.
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The development of artificial intelligence (AI) techniques that can assist with the creation and analysis of digital content is a broad and challenging task for researchers. This topic has been most prevalent in the field of game AI research, where games are used as a testbed for solving more complex real-world problems. One of the major issues with prior AI-assisted content creation methods for games has been a lack of direct comparability to real-world environments, particularly those with realistic physical properties to consider. Creating content for such environments typically requires physics-based reasoning, which imposes many additional complications and restrictions that must be considered. Addressing and developing methods that can deal with these physical constraints, even if they are only within simulated game environments, is an important and challenging task for AI techniques that intend to be used in real-world situations. The research presented in this thesis describes several approaches to creating and analysing levels for the physics-based puzzle game Angry Birds, which features a realistic 2D environment. This research was multidisciplinary in nature and covers a wide variety of different AI fields, leading to this thesis being presented as a compilation of published work. The central part of this thesis consists of procedurally generating levels for physics-based games similar to those in Angry Birds. This predominantly involves creating and placing stable structures made up of many smaller blocks, as well as other level elements. Multiple approaches are presented, including both fully autonomous and human-AI collaborative methodologies. In addition, several analyses of Angry Birds levels were carried out using current state-of-the-art agents. A hyper-agent was developed that uses machine learning to estimate the performance of each agent in a portfolio for an unknown level, allowing it to select the one most likely to succeed. Agent performance on levels that contain deceptive or creative properties was also investigated, allowing determination of the current strengths and weaknesses of different AI techniques. The observed variability in performance across levels for different AI techniques led to the development of an adaptive level generation system, allowing for the dynamic creation of increasingly challenging levels over time based on agent performance analysis. An additional study also investigated the theoretical complexity of Angry Birds levels from a computational perspective. While this research is predominately applied to video games with physics-based simulated environments, the challenges and problems solved by the proposed methods also have significant real-world potential and applications.
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There is now a considerable amount of research on the deficiencies of additively separable preferences for effective modelling of economically meaningful behaviour. Through analysis of observational data and the design of suitable experiments, economists have constructed progressively more realistic representations of agents and their choices. For intertemporal decisions, this typically involves a departure from the additively separable benchmark. A familiar example is the recursive preference framework of Epstein and Zin (1989), which has become central to the quantitative asset pricing literature, while also finding widespread use in applications range from optimal taxation to fiscal policy and business cycles. This thesis presents three essays which examine mathematical research questions within the context of recursive preferences and dynamic programming. The focus is particularly on showing existence and uniqueness of recursive utility processes under stationary and non-stationary consumption growth specifications, and on solving the closely related problem of optimality of dynamic programs with recursive preferences. On one hand, the thesis has been motivated by the availability of new and unexploited techniques for studying the aforementioned questions. The techniques in question primarily build upon an alternative version of the theory of monotone concave operators proposed by Du (1989, 1990). They are typically well suited to analysis of dynamic optimality with a variety of recursive preference specifications. On the other hand, motivation also comes from the demand side: while many useful results for dynamic programming within the context of recursive preferences have been obtained by existing literature, suitable results are still lacking for some of the most popular specifications for applied work, such as common parameterizations of the Epstein-Zin specification, or preference specifications that incorporate loss aversion and narrow framing into the Epstein-Zin framework, or the ambiguity sensitive preference specifications. In this connection, the thesis has sought to provide a new approach to dynamic optimality suitable for recursive preference specifications commonly used in modern economic analysis. The approach to examining the problems of dynamic programming exploits the theory of monotone convex operators, which, while less familiar than that of monotone concave operators, turns out to be well suited to dynamic maximization. The intuition is that convexity is preserved under maximization, while concavity is not. Meanwhile, concavity pairs well with minimization problems, since minimization preserves concavity. By applying this idea, a parallel theory for these two cases is established and it provides sufficient conditions that are easy to verify in applications.
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This thesis investigates active noise control over a large spatial region using efficient control systems. Active noise control (ANC) utilises secondary sound sources to cancel primary noise based on the principle of destructive interference, and has the advantage of high flexibility and easy adaptability. ANC over a large spatial region (spatial ANC), which requires multiple sensors and multiple secondary sources in the system, creates a large-sized quiet zone for multiple listeners in three-dimensional spaces. The existing multichannel approaches are not very efficient in spatial ANC, as the noise cancellation is optimized only around the error sensors. This thesis provides new adaptive solutions for spatial ANC in general noise fields and optimal methods for spatial ANC in sparse noise fields. In terms of adaptive solutions for spatial ANC in a general noise field, our approach is to utilize the wave-domain signal processing technique. Several outcomes resulting from this approach are (1) the design of the feedback wave-domain ANC system, and derivation of the filtered-x least mean square wave-domain approaches; (2) systematical formulation of the wave-domain ANC into different minimization problems and different updating variables, and derivation of four normalized wave-domain approaches. We show that, compared to the conventional multichannel approaches, the proposed wave-domain ANC approaches can achieve significant noise reduction over the entire spatial region with faster convergence speed. In terms of the optimal methods for spatial ANC in a sparse noise field, our approach is to incorporate the l1-norm constraint from compressive sensing into the spatial ANC. Several outcomes resulting from this approach are (1) derivation of the l1-constrained multichannel approaches; (2) derivation of the l1-constrained wave-domain approach. We show that, compared to the conventional multichannel approaches, the proposed l1-norm constrained approaches can reduce the number of active secondary sources with faster convergence speed. In addition, this thesis investigates the best possible spatial ANC performance for a given system, by analyzing the signal space spanned by the secondary sources within a given acoustic environment. The proposed subspace method can obtain best possible ANC performance and is demonstrated to be a feasible solution, especially when the secondary sources are not sufficient to cover all orthogonal spatial modes according to the spherical harmonic theory.
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This thesis revisits a challenging classical problem in geometric computer vision known as "Non-Rigid Structure-from-Motion" (NRSfM). It is a well-known problem where the task is to recover the 3D shape and motion of a non-rigidly moving object from image data. A reliable solution to this problem is valuable in several industrial applications such as virtual reality, medical surgery, animation movies etc. Nevertheless, to date, there does not exist any algorithm that can solve NRSfM for all kinds of conceivable motion. As a result, additional constraints and assumptions are often employed to solve NRSfM. The task is challenging due to the inherent unconstrained nature of the problem itself as many 3D varying configurations can have similar image projections. The problem becomes even more challenging if the camera is moving along with the object. The thesis takes on a modern view to this challenging problem and proposes a few algorithms that have set a new performance benchmark to solve NRSfM. The thesis not only discusses the classical work in NRSfM but also proposes some powerful elementary modification to it. The foundation of this thesis surpass the traditional single object NRSFM and for the first time provides an effective formulation to realise multi-body NRSfM. Most techniques for NRSfM under factorisation can only handle sparse feature correspondences. These sparse features are then used to construct a scene using the organisation of points, lines, planes or other elementary geometric primitive. Nevertheless, sparse representation of the scene provides an incomplete information about the scene. This thesis goes from sparse NRSfM to dense NRSfM for a single object, and then slowly lifts the intuition to realise dense 3D reconstruction of the entire dynamic scene as a global as rigid as possible deformation problem. The core of this work goes beyond the traditional approach to deal with deformation. It shows that relative scales for multiple deforming objects can be recovered under some mild assumption about the scene. The work proposes a new approach for dense detailed 3D reconstruction of a complex dynamic scene from two perspective frames. Since the method does not need any depth information nor it assumes a template prior, or per-object segmentation, or knowledge about the rigidity of the dynamic scene, it is applicable to a wide range of scenarios including YouTube Videos. Lastly, this thesis provides a new way to perceive the depth of a dynamic scene which essentially trivialises the notion of motion estimation as a compulsory step to solve this problem. Conventional geometric methods to address depth estimation requires a reliable estimate of motion parameters for each moving object, which is difficult to obtain and validate. In contrast, this thesis introduces a new motion-free approach to estimate the dense depth map of a complex dynamic scene for successive/multiple frames. The work show that given per-pixel optical flow correspondences between two consecutive frames and the sparse depth prior for the reference frame, we can recover the dense depth map for the successive frames without solving for motion parameters. By assigning the locally rigid structure to the piece-wise planar approximation of a dynamic scene which transforms as rigid as possible over frames, we can bypass the motion estimation step. Experiments results and MATLAB codes on relevant examples are provided to validate the motion-free idea.
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Mucosal lymphoid tissues like human tonsils are colonized by bacteria and exposed to ingested and inhaled antigens, requiring tight regulation of immune responses. Antibody responses are regulated by follicular helper T cells (TFH) and Foxp3+ follicular regulatory T cells (TFR). Here we describe a subset of human tonsillar follicular T cells (TF) identified by expression of TFH cell markers and CD25 that are the main source of T cell-derived IL-10 in the follicle. Despite lack of FOXP3 expression, CD25+ TF cells resemble Tregs in high CTLA4 expression, low IL-2 production, and their ability to repress T cell proliferation. IL-10 boosts conversion of human tonsil TFH cells into FOXP3-expressing cells, possibly promoting peripherally- induced TFR cells at mucosal sites. CD25+ TF cell-derived IL-10 inhibits B cell class-switching to IgE. In children, serum total IgE titers were inversely correlated with the frequencies of tonsil CD25+ TF cells and IL-10-producing TF cells but not with total Tregs, TFR or IL-10-producing T cells. Thus, CD25+ TF cells emerge as a subset with unique T and B cell regulatory activities that may help prevent atopy.
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Anthropogenic carbon dioxide released into the atmosphere is taken up by the oceans. The most profound change has been the decline in ocean pH as it is likely to impact calcifying marine organisms.. In chapter 2, a method utilising purified Bromophenol Blue (BPB) as an indicator to make simple one-point alkalinity measurements via spectrophotometric detection was developed. Our purified BPB dye was characterised over a range of temperatures and salinities and using the absorbance ratio (R (t) = 25 A590/A436) via equation: pH=pK_a +log[((R_([25])-e_1))/((e_2-R_([25]).e_3))] where e1, = 0.00533, e2 = 2.232, e3 = 0.0319, the pH was calculated. The pKa of purified BPB was also determined as 3.513. The method used for the alkalinity of ANU in-house standard and CRM had an uncertainty of +- 1.5 umol kg-1. Comparing the results to unpurified BPB dye, the uncertainty for alkalinity measured was slightly higher approximately plus minus 3-4 umol kg-1. Thus, for experiments that does not require high precision alkalinity measurements (>=4 umol kg-1), then utilisation of the impure BPB could be suitable. The one-point titration method using purified BPB was tested on seawater samples collected from algal flats at One Tree Island, Australia. The method proved to be suitable for producing accurate and precise alkalinity data i.e. approximately 10-15 samples can be determined per hour. In chapter 3 we present the results of open algal pools and the dome experiments conducted on algal ridges to quantify fluxes of calcium carbonate production and dissolution which are isolated from surrounding ocean waters for approximately 3 - 4 hours. The pH and total alkalinity measurements were made for samples collected from algal pools and the dome experiments. During the day, pH increased from 8.1 to 8.7 pH units while alkalinity decreased from around 2200 to 2000 umol kg-1 this is consistent to photosynthesis and high magnesium- calcite production. During the night the opposite was observed, pH decreased from 7.8 to 7.5 and alkalinity increased from around 2300 to 2500 umol kg-1, via respiration and the dissolution of organic matter. The net production and dissolution rates were half of those observed for a nearby back reef when compared to day and night time periods. An automated spectrophotometric system that monitors changes in ocean pH and alkalinity in culture and field experiments simultaneously was developed in chapter 4. The pH-alkalinity spectrophotometric system was calibrated against multiple certified reference materials (CRM) and the in-house ANU standards. High precision range of pH and total alkalinity that is +- 0.0024 - 0.0059 pH units (n = 10) and +-0.84 - 1.07 umol kg-1 (n=10) were obtained respectively. The system was connected to ANU coral reef culturing tank to measure pH and total alkalinity for three months (mid-July, 2015 to mid-October, 2015). The system was also tested at One Tree Island, Australia. The field deployment of the system reveals significant diurnal variability in both pH and alkalinity at One Tree Island. Carbonate chemistry and metabolic processes on coral reefs over time enables the changes in coral calcification rates to be quantified and often used to predict future changes to calcium carbonate production. The pH and total alkalinity measurements will give an understanding of how ocean acidification and other environmental factors will impact coral reefs. Our new automated spectrophotometric pH-alkalinity system is portable and could be easily adapted for in situ measurements on ships and remote locations.
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C-Terminal amidated peptide hormones regulate numerous physiological process and are associated with many pathological conditions. Their C-terminal amidation is exclusively catalysed by the enzyme peptidylglycine alpha-amidating monooxygenase (PAM), which has two subunits: peptidylglycine alpha-hydroxylating monooxygenase (PHM; EC 1.14.17.3) and peptidyl-alpha-hydroxyglycine alpha-amidating lyase (PAL; EC 4.3.2.5). In the present study, the substrate specificity and inhibition of the PAM sourced from DMS53 human small cell lung cancer cells were investigated. A peptide consensus sequence N-Ac-Gly-(S)-Pro-Gln-(S)-Arg-(S)-Phe-Gly-COOH was constructed from the human amidated peptide hormone database, and a library of peptide substrates was designed by varying the amino acids located at the penultimate and antepenultimate positions from the C-terminus. These peptides were synthesised by solid phase peptide synthesis and studied in a competitive PHM binding assay. The results indicated that human glycine-extended hormone precursors having -Arg-Phe-Gly-COOH are likely to bind to PHM effectively in living bodies with IC50 values around twenty micro molar and those having -Asp-Phe-Gly-COOH and -Ala-Phe-Gly-COOH are likely to bind with IC50 values around seventy micro molar. The results also show that antepenultimate amino acids affect binding to PHM but to a lesser degree than the effect of penultimate amino acids. In a prodrug study, the anti-cancer drug Bexarotene was synthetically extended with a glycine to obtain a derivative that was expected to be cleaved by PAM and then deliver a cytotoxic drug. However, the derivative compound showed poor binding to PHM at the millimolar level, but had a similar cytotoxic activity against DMS53 cells to its parent agent. Unlike Bexarotene, a previous study showed that the glycine derivative of Temozolomide (another anti-cancer drug) has strong binding to PHM at micromolar concentration, but somehow does not convert to Temozolomide by PAM. One possible reason is that the glycine derivative possessing an imidazole moiety could inhibit PHM by metal chelation. To investigate this, a structurally-similar molecule N-Ac-(S)-His-Gly-COOH was tested and found to be processed by PAM and not undergo copper coordination. This implies that the glycine derivative of Temozolomide is unlikely to chelate the copper of the PHM active site. To investigate PHM and PAL activity simultaneously, a new PAM assay with a direct, rapid and sensitive HPLC-MS system was established. With this new assay the PAL inhibitor N-Ac-Phe-pyruvate and analogues were evaluated in terms of PAM inhibition through isolated enzyme competitive assays. This demonstrated that N-Ac-Phe-pyruvate is a PAL inhibitor at the nanomolar level against the medium PAM from DMS53 cells and deprotonation of its enol form results in a decrease of PAL inhibition. By using the established HPLC-MS detection system, the intermediate of the C-terminal amidation of calcitonin-Gly (CTG), alpha-hydroxyglycine-extended calcitonin (HO-CTG), was detected in the culture medium of DMS53 cells. This is the first time HO-CTG produced by cells has been detected. With and without a PAL inhibitor, the concentration of the HO-CTG in the medium sample was found to be more than two orders of magnitude lower than those of the corresponding substrate and amidated product, suggesting the PAL catalysis is much faster than PHM catalysis, and PHM catalysis is the rate-limiting step of amidation of calcitonin in human cells.
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Although the 1982 United Nations Convention on the Law of the Sea ('LOSC') separates ocean space into maritime zones, and delineates the rights and duties of coastal States over specific activities and resources within each zone, there remains significant uncertainty about the extent and limit of that jurisdiction - particularly with respect to the living resources of the 200 nautical mile exclusive economic zone ('EEZ'). This thesis addresses this gap by asking the follow question: What is the nature and extent of coastal State jurisdiction over living resources in the EEZ under contemporary international law? The objective of this research is twofold: first, to reach a specific conclusion about the substantive, technical extent of coastal State jurisdiction over living resources in the EEZ under the relevant provisions of the LOSC; and second, to formulate a broader conclusion about the underlying nature of coastal State jurisdiction with respect to those resources, in a manner that is consistent with both the framework of the LOSC and the general rules of international law. The thesis adopts an inductive approach, reviewing and analysing the practice of 145 coastal States by reference to the rules of international law, in order to articulate and justify a contemporary statement regarding the nature and extent of coastal State jurisdiction over the living resources of the EEZ. In order to ensure a comprehensive analysis, the thesis examines: - the type of 'fishing activities' and 'fishing vessels' that may be regulated by the coastal State on the basis of its sovereign rights over living resources; - the extent and expression of prescriptive jurisdiction that may be exercised by the coastal State with respect to foreign vessels fishing under licence in the EEZ; - the extent to which - and the manner in which - jurisdiction may be exercised by the coastal State over unlicensed foreign fishing vessels in transit through the EEZ; - the manner in which enforcement jurisdiction may be exercised by the coastal State over foreign fishing vessels within the EEZ; and - the circumstances under which - and the way in which - enforcement powers may be exercised by the coastal State over foreign fishing vessels beyond the EEZ following hot pursuit. The underlying hypothesis of the thesis is that coastal States use a variety of tools and techniques to maximise the extent of their jurisdiction. This has been clearly borne out in this research, which demonstrates that States adopt approaches that 'thicken' their jurisdiction within the EEZ, 'project' their jurisdiction beyond the EEZ, expand the effect of their jurisdiction through cooperation, and enhance the application of their jurisdiction through the use of technology. More broadly, the wide range of law and practice examined in this thesis clearly shows that the nature of coastal State jurisdiction over living resources in the EEZ is flexible, but functional. It consists of a broad discretion, which is exercisable within functional limits that are determined on the basis of reasonableness and by reference to the balance of rights and interests in the EEZ.
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