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Augmented Revolution: The Role of Social Media in the Arab Spring and the Hong Kong Umbrella Movement
No full textTheoretical thesis.Bibliography: pages 120-139.Introduction -- Literature Review -- The global digital sphere for social movements -- Social media and the emergence of the global digital sphere -- The global digital sphere and the digital public sphere -- Activists and social media use -- The transformation of activists -- The restructuring of social networks online -- Social movements in the era of social media -- Twitter /Facebook revolution? -- Social media and protest mobilisation -- Chapter 1 Social Movements in Arab and Hong Kong -- Chapter 2 Virtualising the Actual World -- Breaking the boundaries -- Truth or 'white lies'? -- 'We are all Khaled Said' -- Chapter 3 Actualising the Virtual World -- Mobilising through posting -- Connective actions and communal spaces -- Who speaks for whom? -- Conclusion - References.This thesis explores the role of social media in social movements. It focuses on how social media changes the environment of communication in social movements; how activists operate in social movements through social media; and how social movements travel from one region to the next through social media. The thesis views social media as an extension of activists' fields of operation, enabling them to fight for change in the actual and virtual worlds simultaneously. Supported by the perspectives of public sphere, networked publics, affective publics and augmented reality, the thesis argues for "augmented revolutions" where online and offline actions interact. The thesis proceeds through a comparative analysis of two social movements where social media played an important role: The Arab Spring in 2011 and the Hong Kong Umbrella Movement in 2014. These case studies show that social media changes the activists' ways to participate, to express and deliver messages, and to mobilise crowds. It enables connective actions and the reconstruction of communal spaces. Based on these findings, this thesis asserts that social media may trigger social movements in other regions.1 online resource (140 pages) illustrations, photograph
Social processing in Williams syndrome, Autism spectrum disorder and Social anxiety disorder
No full textThesis by publication.Includes bibliographical references.General introduction -- Paper 1. Extending the positive bias in Williams syndrome : the influence of biographical information on attention allocation -- Paper 2. Attention for faces in Williams syndrome, Autism spectrum disorder and Social anxiety disorder : the role of biographical information -- Paper 3. Emotional recognition in Williams syndrome, Autism spectrum disorder and Social anxiety disorder : the influence of biographical information -- Paper 4. Visual attention and executive function in Williams syndrome, Autism spectrum disorder and Social anxiety disorder : the role of biographical information -- Paper 5. Visual scanpaths and social approach judgements in Williams syndrome, Autism spectrum disorder and Social anxiety disorder : use of biographical rather than affective stimuli -- General discussion -- Ethics approval.Williams syndrome (WS), Autism Spectrum Disorder (ASD) and Social Anxiety Disorder (SoAD) are conditions which present with contrasting social profiles. With respect to social processing and social behaviour, these conditions appear to represent distinct points on a continuum, from increased social approach in WS, to social withdrawal and avoidance in ASD and SoAD. While social processing anomalies have been established across WS, ASD and SoAD, research to date has largely investigated each condition in isolation. Moreover, while it is known that individuals with these conditions display social processing abnormalities in response to emotional face stimuli, it is not known whether similar abnormalities are observed in response to biographical stimuli.This thesis aimed to assess the influence of biographical information on social processing in individuals with WS, ASD or SoAD, using a cross-disorder comparison. A biographical learning paradigm was adapted and implemented across five papers, specifically investigating the influence of biographical information on attention allocation, emotion recognition, the salience of certain face regions and approach/avoidance decisions.The principal findings of this thesis are as follows: 1) Biographical information influences attention allocation, with WS individuals exhibiting an attention bias for trustworthy biographical faces, while SoAD individuals display an attention bias for untrustworthy biographical faces. 2) Biographical information does not influence the direct perception of emotional expressions, however; 3) Biographical information influences the salience of the eye region of faces, with WS individuals spending more time looking at the eyes of trustworthy biographical faces, while ASD and SoAD individuals spend more time looking at the eyes of untrustworthy biographical faces. 4) Across WS, ASD and SoAD, social approach judgments are directly influenced by biographical information.Thus, using a cross-disorder comparison, this thesis showed that biographical information does influence social processing across WS, ASD and SoAD, largely in the direction that one would predict based on their divergent social profiles. The current thesis has contributed to the literature on social processing in WS, ASD and SoAD and provides important preliminary evidence of how biographical information may influence social processing in disorders featuring distinct social profiles.Mode of access: World wide web1 online resource (ix, 320 pages
Parasite-host interactions during the blood and liver stage of rodent malaria parasites
No full textThesis by publication.Cotutelle thesis with Universität Bern (the University of Bern (Switzerland)).Includes bibliographical references.1. Introduction -- 2. Publication and manuscripts -- 3. Discussion -- Appendices.Malaria is a parasitic disease which puts almost half of the world's population at risk of infection. It is caused by Plasmodium, a parasite transmitted by Anopheles mosquitoes. During its life cycle in the vertebrate host, the malaria parasite invades and multiplies in hepatocytes and in red blood cells. During invasion of sporozoites and merozoites, the host cell membrane invaginates around the parasite to form the parasitophorous vacuole membrane (PVM). The membrane is extensively remodeled by the parasite: host cell membrane proteins are removed and parasite proteins are incorporated. The PVM shields the parasite from a direct attack by cytosolic host cell immune responses and provides the host-parasite interface. Important roles of the PVM are nutrient acquisition, excretion of waste products and export of host-targeted proteins which add to parasite fitness and virulence. Finally, egress is critical for parasite release from its host cell and the first step is PVM disintegration. PVM biology and remodeling is of great interest, but despite all of these important tasks fulfilled by proteins in the PVM, the composition is not yet clear. Here, a proximity labeling technique (BioID) was used to identify PVM or PVM-interacting proteins in P. berghei blood stage parasites. Using this technique, many of the already known PVM proteins were found. Apart from known resident PVM proteins, I detected several proteins that were that were hitherto unknown as PVM proteins. Uncharacterized protein candidates were endogenously GFP-tagged and analyzed using live- and fixed-cell microscopy during the liver and the blood stage. Using this approach, I was able to identify several novel PVM proteins, and proteins that come in close proximity to the PVM. During the intraerythrocytic symptomatic blood stage, Plasmodium digests up to 70% of host hemoglobin. Heme is an essential component of a number of proteins including hemoglobin and is essential for life. It is synthesized by a pathway involving at least eight enzymatic steps, and deficiency of any of these result in porphyria. Despite the abundance of hemoglobin and heme during the blood stage, the parasite expresses all enzymes of its canonical heme pathway, which can facilitate the de novo heme synthesis. Previous research has indicated that the parasite heme pathway is non-essential during the blood stage, and that the deficiency of host heme enzymes can influence parasite growth. That Plasmodium can be greatly influenced by the host background is well established. Here we hypothesized that host porphobilinogen deaminase (PBGD) and coproporphyrinogen oxidase (CPOX), two additional heme pathway enzymes, play a role during the blood stage. To facilitate this goal, in-depth studies by using rodent malaria species were utilized to infect mice deficient in PBGD and CPOX. Blood from porphyric patients was infected with P. falciparum and parasite growth was significantly inhibited. Host PBGD was localized to the parasite periphery which could indicate that the parasite imports this enzyme during the blood stage. PBGD deficient mice are more resistant to malaria infection which suggests that Plasmodium relies on host PBGD to sustain its growth in erythrocytes and cause blood-stage infection. CPOX deficient mice displayed an increased survival, probably due to iron deficiency anemia, but the exact underlying mechanism remains to be elucidated. A novel role for PBGD and CPOX was described in this thesis adding to the understanding of host-pathogen interactions during the blood stage. Together this thesis has identified a number of novel PVM proteins during the blood and liver stage which will help to gain a deeper understanding of PVM biology. Deficiency of host enzymes can influence Plasmodium and here two novel host proteins, PBGD and CPOX are added to them. This thesis increased the understanding of host-parasite interactions during the blood and liver stage of Plasmodium.1 online resource (150 pages : illustrations, map
Pulsed laser sources utilising liquid crystals as intracavity modulators
No full textEmpirical thesis.Bibliography: pages 165-191.1. Motivation -- 2. Background - theory and experimental methods -- 3. Liquid crystal cell -- 4. Liquid crystal Q-switched waveguide chip lasers -- 5. Compact Q-switched waveguide laser - an application -- 6. Summary and future work -- List of publications -- References.A range of techniques for fabricating optical waveguides in actively doped media has previously been developed. Macquarie University has specialised in the femtosecond laser direct-write technique, a flexible method that enables the inscription of three-dimensional structures into transparent media. By inscribing depressed-cladding waveguides into doped fluoride glass chips, continuous-wave (CW) lasers with extraordinarily large fundamental mode-field diameters have been realised. However, in order to generate optical pulses with high peak-power levels, an actively controlled intracavity loss modulator would be required. While the use of bulk acousto-optic modulators has been demonstrated, the waveguide chip laser architecture is best utilised with a modulator that is compatible with a monolithic and integrated design.In the present work, a novel type of a liquid-crystal based transducer was utilised as an intracavity loss modulator that can be integrated onto the laser chip, opening up the possibility of realising monolithic miniaturised actively Q-switched high peak-power laser sources. This liquid crystal cell was initially developed by our collaborator in the context of distributed sensor networks and therefore its switching behaviour on a microsecond to sub-microsecond timescale had to be studied first. Next, the cell was employed as an active Q-switch in an ytterbium glass waveguide laser, resulting in peak power levels approaching 100 W. Further,the use of this technology in laser chips based on polarisation-maintaining waveguides in crystalline materials was investigated in the visible spectral region, and this approach was also extended towards the mid-infrared spectral region with the aim of utilising nonlinear optical effects in chalcogenide fibres to generate broadband radiation in the important mid-infrared fingerprint region of the optical spectrum.Finally, the feasibility of using the liquid-crystal modulator as a mode-locking device in fibre lasers was investigated and a fibre laser that can be switched between mode-locked, Q-switched and CW operation was demonstrated.Mode of access: World wide web1 online resource (xviii, 191 pages) colour illustration
Landscape genetic connectivity and sex-specific responses in a range expanding damselfly
No full textThesis by publication.Bibliography: pages 46-56.Introduction -- Materials and methods -- Results -- Discussion -- Conclusion -- Acknowledgements -- References -- Supplementary material.Range shifts induced by climate change have been documented in many insect taxa. The damselfly, Ischnura elegans, is undergoing a poleward range expansion in northern Europe showing local adaptation to environmental conditions at the range edge in Sweden. However,the role of neutral genetic connectivity and sex-specific responses in the range expansion process is unknown. We examine relative abundance, sex-specific landscape genetic relationships and morphological variation in I. elegans along a ~600km range expansion axis. We analysed 29 landscape resistance surfaces against genetic distances (FST and G`ST) calculated from 3,554 RAD seq-derived neutral Single Nucleotide Polymorphisms (SNPs) from 25 sites (n = 426 individuals). Resistance modelling showed cooler mean annual temperatures limited genetic connectivity linearly, with greater resistance at colder range limit sites. Relative site abundances were reduced along the sampled gradient; however,genetic diversity showed no significant change, suggesting recent colonisations. Results were consistent with female-biased dispersal, with females showing reduced temperature resistance to gene flow and a small, almost linear effect of land cover type that was not observed in males. Female, but not male, wing length also increased towards the range limit. Our findings demonstrate sex-specific morphological and landscape genetic responses during a climate-change induced range expansion.Mode of access: World wide web1 online resource (69 pages) colour illustrations, colour map
Research on theory and techniques of energy management for energy-harvesting powered wireless communications
No full textEmpirical thesis.Bibliography: pages 135-148.1. Introduction -- 2. Provisioning quality-of-service to EH-powered WSN communications -- 3. Smart-grid powered MIMO downlink communications -- 4. Smart-grid powered CoMP communications -- 5. Thesis conclusion and future work -- Appendices -- References.Energy harvesting (EH) is the process of capturing renewable energy from the environment and converting it into usable electrical energy. In wireless communication systems, collecting renewable energy from the environment is a key factor in building self-sustainable networks. In addition, EH-powered wireless communications help reduce carbon footprint and enable "green" communications to solve important issues such as haze, global warming, and climate change. Due to these ecological and economic reasons, various types of EH-powered wireless communications have become current research hotspots.However, challenges arise in EH-powered wireless communication systems. First, the reliability of data transmissions is challenged due to the inherent randomness and instability of environmental energy sources. Second, due to the limited energy provided by environmental energy sources, how to make full useof the limited energy and ensure the systems obtain optimal performances is also a stringent subject. Therefore, for EH-powered wireless communication systems, we need to conduct reasonable energy management and resource allocation to ensure reliable and efficient communications, thus optimizing system performances.On the one hand, for EH-powered WSN links, we optimize energy management for the transmitters, so that the collected energy is properly distributed to data transmissions. On the other hand, we introduce smart-grid technology to jointly provide renewable energy and grid's persistent energy to base stations (BSs) in cellular networks, compensating for unstable and insufficient EH power supply. Through the optimal energy management of BSs, we make full use of renewable energy, maximize the system throughput or minimize the electricity transaction cost with the grid, while satisfying users' quality of service (QoS).Optimal energy management is first investigated for EH-powered WSN links.A new "dynamic string tautening" algorithm is proposed to generate the most energy-efficient offine schedule for delay-limited traffc of transmitters. The algorithmis based on two key findings derived through convex formulation and resultant optimality conditions, specifies a set of simple but optimal rules, and generates the optimal schedule with a low complexity. The proposed algorithm is also extended to online scenarios, where the transmit schedule is generated on-the-fly.An infinite time-horizon resource allocation problem is then formulated to maximize the time-average downlink throughput for smart-grid powered multiple input multiple-output (MIMO), subject to a time-average energy cost budget. By using the advanced time decoupling technique, a novel stochastic subgradient based online control (SGOC) approach is developed for the resultant smart-grid powered communication system. It is established analytically that the proposed online control algorithm is able to yield a feasible and asymptotically optimal solution without a-priori knowledge of the stochastic system information.Last, a two-scale stochastic control framework is put forth for smart-grid powered coordinated multi-point (CoMP) systems. The energy management taskis formulated as an infinite-horizon optimization problem minimizing the time average energy transaction cost. Leveraging the Lyapunov optimization approach as well as the stochastic subgradient method, a two-scale online control (TSOC) approach is developed for the resultant smart-grid powered CoMP systems. Using only historical data, the proposed TS-OC makes online control decisions at two timescales, and features a provably feasible and asymptotically near-optimal solution.Mode of access: World wide web1 online resource (xxvi, 148 pages) graph
A new institutional economics analysis of the history of the regulation of the .cn (China) country-code top-level domain from 1990 to 2004
No full textTheoretical thesis.Bibliography: 255-339.1. Introduction and aims -- 2. Theoretical approach and methodology -- 3. New institutional economics theory -- 4. Institutional formation of the .cn ccTLD (1990-1997) – legal transplantation -- 5. The first institutional change in 2002 – legal localisation -- 6. The second institutional change in 2004 – legal characterisation -- 7. Conclusion -- Bibliography.The Domain Name System (DNS) operates at the literal root of the Internet. Governments can control cyberspace communications through controlling the DNS and countries can claim cyberspace sovereignty via their administration of country-code Top-Level Domains (ccTLDs). In order to understand how China governs the Internet and its cyberspace, it is necessary to know how Chinese governments regulate the DNS. Under the theoretical framework of New Institutional Economics theory, combining qualitative analysis, historical research, case studies, and triangulation research, this dissertation analyses the institutional formation and institutional change process for the .cn ccTLD administrative regulations. It also explores how Chinese governments’ governance practices are affected and how the constraints of politics, law, economics and technology improve and restrain the institutional formation and change of the .cn ccTLD administrative regulations. The structure of the thesis includes institutional transplantation, institutional localization and institutional specialization.This dissertation proposes and tests three key arguments: (1) within the context of the DNS and characterized with connectivity and hierarchy, and domain name administrative regulations with a hierarchic administrative mode, domain name technological path dependency led to China’s domain name administrative regulation’s path dependency; (2) the institutional change of the Administrative Measures on China’s Domain Names resulted from the synthesis of endogenous and exogenous institutional change factors; (3) Chinese governments sometimes supply or tolerate inefficient institutional arrangements so as to achieve other higher goals. Overall, this dissertation provides evidence that the Chinese governments tolerate, develop, and/or promote institutions and technologies which might increase the quality of citizens’ lives and which might develop the domestic economy, but constrain, supervise, or/and forbid institutions and technologies perceived to risk causing damage to China’s stability and unity.Mode of access: World wide web1 online resource (x, 340 pages) 1 colour ma
The cross in the visual culture of Christian Egypt: Byzantine to Fatimid eras
No full textTheoretical thesis.Bibliography: pages 268-291.Chapter 1. Introduction -- Chapter 2. Survey of crosses, Byzantine to Fatimid era -- Chapter 3. Material and techniques -- Chapter 4. Design and symbolism -- Chapter 5. Design, dating and location -- Chapter 6. Design in context -- Chapter 7. Findings and conclusion -- References -- Appendices.Egypt is better known for pharaohs, and their legacy, than for Christianity. Yet, in the early centuries after Christ, the Christian monastic movement grew roots and took shape in Egypt. Early adopters of the new faith in Egypt contributed to the development of Christian contemplative life. More relevant to this study, they als oexpressed themselves through material culture.This thesis focuses on representations of the cross, that most fundamental symbol of the Christian faith. More specifically, it is an art historical exploration of the varied designs of the crosses of Christian Egypt, from the fourth to the twelfth century. The corpus, across the monastic landscape, is rich and diverse, reflecting the syncretistic society that commissioned and produced it. The designs are remarkable and sometimes unique. Representations occur in wall paintings, funerary sculpture, architectural features in stone and wood, and on a wide range of domestic and liturgical objects.The study commences with a survey of monastic sites across Egypt, and the identification of significant crosses, acknowledging that the size of the corpus has been diminished by many factors including deliberate destruction, questionable excavation methods of early archaeologists and bounty hunters, ongoing infrastructure projects and the pressures of population. Nonetheless, the thesis is underpinned by a collection of around four hundred images, sourced mainly from archaeological reports and museum collections, which has allowed the designs to be analysed.The image collection has been essential to the project. Through it a typology based on design elements has been proposed. The likely influences apparent in the images have been examined and the symbolism of the motifs accompanying the crosses have been explored. Settings and contexts in which the varied designs occur have also been analysed. Designs have been charted against a timeline, and maps showing the distribution of types have been created to support the text.Mode of access: World wide web1 online resource (ix, 291, 27 pages) map
Buildups from the lower Cambrian Hawker Group, Arrowie Basin: construction, facies and geochemistry
No full textEmpirical thesis.Bibliography: pages 49-51.1. Introduction -- 2. Aims -- 3. Geological setting and biostratigraphy -- 4. Buildup types of the Lower Cambrian -- 5. Materials & methods -- 6. Results -- 7. Discussion -- 8. Conclusion -- References.The lower Cambrian carbonates of the Flinders Ranges are richly fossiliferous and contain a highly diverse assemblage of archaeocyaths. Lower Cambrian buildups formed by the aggregation of archaeocyaths, cemented together by calcified microbes, occurred on shallow carbonate platforms in low latitudes. The development of these buildups provides an early example of ecosystem engineering by archaeocyaths. The rigidity of these buildups created topographic relief, while the heterogeneity produced internal cavities that enhanced habitat complexity within benthic ecospace.In this study, buildup architecture is mapped to reveal the heterogeneity, structure and proportional relationship between archaeocyaths and calcified microbes. This centimetre-scale foundation provides contextual framework for deciphering the buildup architecture at millimetre- to micrometre-scale. This scale focuses on the biological composition of archaeocyaths, calcified microbes and associated faunas within the buildup. Additionally, this scale reveals the interaction between individual archaeocyaths and the calcified microbial support, with relevance to bioconstruction rigidity and the development of syndepositional cavities.Mode of access: World wide web1 online resource (v, 51 pages) illustrations (some colour
The role of a universal vascular access system in locoregional chemotherapy for solid tumours
No full textEmpirical thesis.Bibliography: pages 147-166.Chapter 1. Introduction -- Chapter 2. Design & development of a UVAS -- Chapter 3. The UVAS as a general vascular access device -- Chapter 4. Liver isolation chemotherapy using the UVAS -- Chapter 5. Discussion part 1 : trial outcomes and future direction -- Chapter 6. Discussion part 2 : mechanisms of the hepatic technique developed -- Chapter 7. Conclusions -- References -- Appendices.Since the advent of chemotherapy, much of the progress gained in the treatment of solid tumours has primarily has been brought about by the advancement of drug designs and chemotherapy combinations. However, in advanced cancers the standard route of intravenous systemic delivery is unable to exploit the full potential of even third generation chemotherapeutic agents and as such, the prognosis for these patients remains grim. Alternatively, locoregional chemotherapy (LRC) techniques focused on delivering chemotherapy as close to the tumour as possible have been able to achieve responses where systemic therapy has failed in some cases. Nonetheless, such techniques are limited to specialised centres, associated with high morbidity and mortality, and are generally not repeatable due to limitations in vascular access technologies.The aim of this thesis was to determine whether a universal vascular access device (UVAS) could be developed which could provide general vascular access and facilitate LRC treatments and if so, to assess the potential of the treatment it can facilitate.A design for a UVAS was developed based on an existing transcutaneous access device as well as the clinical requirements deemed necessary to enable LRC treatments. A meta-analysis was carried out of devices with similar features to obtain an understanding of the risks that may accompany the use of such a device. The developed UVAS was then used in 5 patients with critical limb ischaemia in a clinical trial as a general vascular access device. Additionally, a new LRC technique was developed with the UVAS and tested in another clinical trial of 10 patients with colorectal liver metastases.The device related outcomes in both studies demonstrated that the UVAS was able to perform its intended functions safely as a general vascular access device and in facilitating LRC treatments. The LRC technique developed demonstrated promising results (30% response rate) in patients that had previously exhausted all other therapies. The intra-arterial pressures measured and the minimal toxicity (grades I-II) reported is suggestive of the level of manipulation achieved within the liver which could potentially be applied to other organs.A UVAS was successfully designed, developed, and proven to be fundamental in being able to administer a new LRC treatment in the form of minimally invasive, repeatable liver organ isolation chemotherapy. A system with such capabilities provides encouragement for further LRC techniques that were previously considered too burdensome to be properly investigated.Mode of access: World wide web1 online resource (166 pages) illustrations (some colour