Dissertations / Theses on the topic 'Space sciences not elsewhere classified'

This study is an investigation in and through media arts practice. It set out to develop a novel type of new media artistic praxis built upon concepts drawn from the disciplines of scientific and cultural ecology. The rationale for this research was based upon my observation as a practising new media artist that existing praxis in the new media domain appeared to operate largely without awareness of the ecological implications of those practices. The thesis begins by explaining key concepts of ecology, spanning the arts and the sciences. It then outlines the thinking of contemporary theorists who propose that the problem of ecology is a critical issue for the 21st century, suggesting that our well-documented ecological crisis is indicative of a more general crisis of human subjectivity. It then records an investigation into particular strategies for artistic praxis which might instigate an active engagement with this problem of ecology. The study employed a methodology based in action research to focus upon the development and analysis of three new artistic works, '#14', 'Public Relations' and 'transit_lounge'. These were used to explore diverse theories of ecology and to hone a series of pointers towards Ecosophical arts/new media praxis. This journey constitutes an emergent theory for new media space design. The thesis concludes with a toolkit of tactics and approaches that other arts/new media practitioners might employ to begin working on the problem of ecology.

This study investigates the perceptive modalities constituted by the multi-screen projection installation and its architectural and spatial forms. The thesis explores the hypothesis that the affective spatial experience created by the spatially configured moving image space (MIS) produces changed spectatorial positions from that of the single screen (or one-directional multi screen). The research asks: How can we understand the spatially configured multi-screen projection installation as constituting a changed aesthetic perception for the spectator? The MIS comprises two major temporalities, the multi-image structure and the mobile spectator whose physical interaction articulates the receptive process. Thus, perception in the MIS is not purely constructed through vision. Instead, the spatio-temporal assemblage shapes other direct sense phenomena. These are the spatial intensities produced by the spatial field, i.e. variable sensations of spatial receptivity, which are not mediated by the gaze but experienced directly by the body. Further, the mobile gaze of the moving spectator intersects with the moving images, and constructs vision as fluid and transient. Merleau-Ponty (2006), first published 1945, proposed that the mobile orientation of the body in space creates changing points of reference and alters both vision and embodied experience of space. The analysis of two inter-related concepts aims to contribute to a new understanding of the MIS. The first is the interstitial modality established by the screen architecture which engenders temporal and spatial gaps that interrupt the process of perception. Interstitiality here serves as an analytical tool in discerning the specific spectatorial positions instituted by individual installations. The second is the process of inter-animation which is constituted by the corporeal interaction of the spectator in the animated space of the MIS. Spatial and temporal effects act upon the body of the viewer. In turn, the viewer negotiates the unfamiliar space and multiple interstices through intuitive reaction. Deleuze (1994), first published 1968, suggested that spatial intensities and differences create immediate sensory impact which is experienced as intuition. Intuition intervenes in the visual process and expands perception from observation and reflection to intuitive action.

Human spatial experience has recently expanded due to the development of location-aware technology. Locative information has become more significant within urban space; as such, related discourses have attempted to focus on the issue as a way in which we acquire locative information when we experience space. Digital location-aware methods enable the demonstration of live densities of telecommunication through which one can infer temporal and spatial factors of live urban situations. When locative telecommunication data is mapped onto urban space, temporal-spatial demographic maps are obtained. Based on these maps, one can infer the correlation between spatial experience and architectural programmes via on site observation and by determining the multi-layered structure of spatial experience via designed data installation. These considerations aim to investigate locative interaction in urban space in order to expand spatial experience. This research begins with two linked theoretical notions: rhythm analysis and heterotopia—in other words, temporality as it relates to our everyday life and spatiality as it relates to our search for ideal space. In addition to these positions, the following discourses are specifically developed to investigate locative interaction in urban space. Firstly, the temporal and spatial patterns of urban activities are investigated in an attempt to grasp current urban interactions. The telecommunication data is then mapped geographically. Secondly, the gap between the endowed architectural programmes and the observed activities in urban space is explored in order to examine the multi-layered structure of urban interaction. Thirdly, the above discussions are synthesised using a design project that interprets epistemic aspects of this initiative. Lastly, urban rhythms and locative virtual layers are suggested as the concept for locative interaction in urban space where architectural programmes become more flexible, thus expanding spatial experience. Two projects demonstrate as applicable scenarios of locative interaction in urban space; they involve a heterotopia finder and a floating gallery over London. This research suggests a new viewpoint from which to consider our world and its digital presence by mapping a ‘live urban space’ using telecommunication data—an initiative that highlights the importance of people as a crucial aspect of our digital surroundings. This research ultimately contributes to expanding urban spatial experience and providing an informative and holistic mapping structure for architecture and urban design, interweaving it with the digital environment.

During the last 30 years computer and videogames have grown into a large entertainment industry of economic as well as cultural and social importance. As a distinctive field of academic inquiry begins to evolve in the form of Game Studies, the majority of approaches can be identified as emerging either from a background of literary theory which motivates a concentration on narrative structures or from a dedicated focus on the rules of video and computer games. However, one of the most evident properties of those games is their shared participation in a variety of spatial illusions. Although most researchers share the view that issues related to mediated space are among the most significant factors characterising the new medium, as of yet, no coherent conceptual exploration of space and spatial representation in video and computer games has been undertaken. This thesis focuses on the novel spatial paradigms emerging from computer and video games. It aims to develop an original theoretical framework that takes the hybrid nature of the medium into account. The goal of this work is to extend the present range of methodologies directed towards the analysis of digital games. In order to reveal the roots of the spatial apparatus at work an overview of the most significant conceptions of space in western thought is given. Henri Lefebvre's reading of space as a triad of perceived, conceived and lived space is adopted. This serves to account for the multifaceted nature of the subject, enables the integration of divergent spatial conceptions as part of a coherent framework, and highlights the importance of experiential notions of spatiality. Starting from Michel Foucault's notion of the heterotopia, game-space is posited as the dynamic interplay between different spatial modalities. As constitutive elements of the dynamic spatial system mobilized by digital games the following modalities are advanced: the physical space of the player, the space emerging from the narrative, the rules, the audiovisual representation and the kinaesthetic link between player and game. These different modalities are examined in detail in the light of a selected range of exemplary games. Based on a discussion of film theory in this context an original model that serves to distinguish between different visual representational strategies is presented. A chapter is dedicated to the analysis of the crucial and often overlooked role of sound for the generation of spatial illusions. It is argued that sound has to be regarded as the privileged element that enables the active use of representational space in three dimensions. Finally the proposed model is mobilised to explore how the work of contemporary artists relates to the spatial paradigms set forth by digital games. The critical dimension of artistic work in this context is outlined. The thesis concludes with a discussion of the impact of the prevalent modes of spatial practice in computer and video games on wider areas of everyday life.

In today’s world, antimicrobial resistance is one of the biggest global health issues that mankind is facing. This most effective way to ensure a wound does not become infected is through cleanliness and continued disinfection of the wound site. There is a lack of new antimicrobial drugs coming to the market due to economical and clinical reasons, this is evident in Lord O’Neill’s 2016 report and is addressed by Professor Dame Sally Davies in Parliament, (“We have reached a critical point and must act now on a global scale to slow down antimicrobial resistance”2). Prescription drugs have led to this epidemic that was highlighted by O’Neill. The latest report (2016) by O’Neill states, it is critical to improve sanitation and hygiene, refrain from overusing antibiotics in agriculture and the environment as well as introducing rapid diagnostics and vaccines3. This is leading to the need for photodynamic antimicrobial chemotherapy (PACT) that involves the use of a reactive oxygen species (ROS), photosensitiser, and light to cause microbial death. PACT is a treatment for resistant and non-resistant pathogens that is included in the treatment of multidrug resistant infections. The approach is to use novel antimicrobial drugs topically, avoiding systemic photo-toxicity, thus leading itself towards topical infection control. Herein, we report the development of a range of novel photosensitisers based on the second generation photodynamic therapeutic dyes (PDT) that are based on the tricyclic isoalloxazine structure of riboflavin, vitamin B2. Photosensitisers were synthesised using similar strategies to the isoalloxazine for a number of reasons: e.g. photoactivity and capability of degradation. In order to investigate which photosensitisers gave the highest reactive oxygen yield, functional group changes were made on the N-phenyl ring by substituting a range of electron withdrawing/donating substituents at different positions (ortho, meta, para). The free amide moiety was used to attach the photosensitiser to a solid support that would act as proof of principal of a photosensitiser attached to a bandage. These dyes show a phototherapeutic response via a Type I and II mechanism upon illumination by light of a selected wavelength. The mechanisms produce highly toxic oxygen-species, such as radical production via Type I pathway and singlet oxygen generation by Type II, thus causing terminal damage to microbes in a short time period. The synthesised photosensitisers are illuminated using blue light (440 - 490 nm) and white light in order to monitor and compare the singlet oxygen and radical yields generated as they absorb approximately at 440 nm, thus blue light being ideal for irradiation. The outstanding singlet oxygen result generated by compound 12c of 172% and a radical production by 11c of 227% show promising generators of cytotoxic species, resulting in microbial death. The synthesised photosensitisers have been tested against two opportunistic microbes (Gram positive and Gram negative bacteria; Staphylococcus aureus (S. aureus), and Escherichia coli (E.coli). They have proven to be problematic from its presence within the healthcare system especially when found on surgical site infections. From the statistics generated for the National Health Service (NHS) in the UK we can see that 52.4 % of S. aureus, and 43.1 % E.coli originates within the hospital environment. Antimicrobial activity was observed for several compounds under different light regimes on and off the solid support. As a result, the best observed MIC value of 0.25 mM/mL was achieved for S. aureus in darkness and in blue light without the polymer support. Additionally, when these compounds were linked to a polymer support (mimicking a bandage), antimicrobial activity was retained when irradiated using blue light at 1.0 mM/mL. These results show potential towards the next generation of antimicrobial disinfection agents. In time, these compounds could be integrated into the healthcare system for use as a new generation of self- cleaning bandages towards post-operative wound disinfection rather than employing front line antimicrobials. This is a moot subject under review in parliament and former UK prime minister has highlighted the concern. In a statement recently released, he states “If we fail to act, we are looking at an almost unthinkable scenario where antibiotics no longer work and we are cast back into the dark ages of medicine" – David Cameron, UK Prime Minister2.

Stroke is the third leading cause of death in the western world, and the primary cause of adult disability. There is a great need for methods to identify patients at risk of stroke and decide appropriate treatment. The main criterion for identifying patients at risk of stroke is the percentage of the narrowing in the carotid arteries, which lead blood from the heart to the brain, which currently is quantified manually. This project is in collaboration with Blackpool Victoria Hospital and Christies Hospital in Manchester. The aim of this project is to develop software methods to improve computer-assisted carotid artery stenosis measurement based on Magnetic Resonance Images. A methodology is therefore presented, based on 3D geometry extracted from Contract-Enhanced MR Angiograms, to identify and segment the internal carotid arteries for stenosis quantification. The MRA data volume is initially automatically reduced, by locating the carotid arteries and creating two volumes of interest, each including a single set of carotids (either left or right). The artery of interest (Internal Carotid Artery - ICA) is identified in each sub-volume automatically, by tracking the carotid bifurcation and selecting the artery branch with no further arterial branches. The central axis of the ICA is consequently determined by calculating and connecting together the centres of gravity (centroids) of the 2D contours of the carotid in the axial plane. Segmentation of the ICA is carried out, perpendicular to the central axis, by applying adaptive thresholds along the ICA central axis based on local image characteristics. Hence, the cross-sectional area of the segmented ICA is then measured at different points along the vessel. The most stenotic area is identified, and a reference region is manually selected. The degree of stenosis is then quantified based on the reference and stenosed area measurements, according to the NASCET criterion. This provides a fully automated methodology to locate, identify, and measure the internal carotid stenosis. It is the first time that such complete methodology that covers the processing of the MRI data until the stenosis measurement is taken is developed and is fully automatic. The segmentation results are thoroughly evaluated against the manual delineations of two clinical experts (each performed the delineations twice), and against two popular segmentation techniques. The results were found successful and perform better than manual measurements and other current techniques. They present smaller variability than manual measurements and are able to deal with irregularities in the arterial structure, where other computerised techniques fail. The suggested methodologies seem promising and able to improve considerably both current clinical practice and other existing methodologies.

There are currently several evaluation methods suited to children within the Child-Computer Interaction (CCI) community. However, these methods are user based leaving a gap in inspection method suited to children, that is, where children will act as the inspection method evaluators. This research focused on how to design an effective and easy to use inspection method where children will perform the evaluation based on their values. To ensure that the above is met, a user centred approach and a mixed methodology was explored and finally resulted in the creation of the Inspection Method for Children (IMCH) with an accompanying guideline. This six stages method could be used by CCI researchers as a guide to develop similar methods for children, by industries to perform inspection method evaluation with children on technologies designed for children and could be used by designers to gather design criteria for children’s technology. The process undertaken within this research to develop the new method is also novel and could be adapted by new and old researchers when adapting method to suit children. Future work will focus on carrying out evaluation with wider age range of children in the method to ensure suitability of the method for more children. Comparative studies of the method with other usability method to determine the effectiveness of the method and as a refinement process to produce a validated and refined IMCH method.

The use of lipid profiles from the immobilised alga Selenastrum capricornuizim was investigated as a potential indicator of heavy metal pollution in freshwater environments. The toxicity of Cu", Zn 2 and Cd2t on algal growth was determined and the effective concentration inhibiting specific growth rate by 50 % (EC5 0) for each metal was found to be 124 pM Cu, 20 pM Zn and 5.7 pM Cd respectively. The Cu 24 EC50 value for immobilised cells was also shown to be 124 j.tM, suggesting that Cu exhibits similar toxic effects on growth in both free and immobilised cells. Studies of the effects of temperature and heavy metal exposure (Cu21, Zn 2 and Cd2 +) on S. caprzcornutum demonstrated that these factors altered the fatty acid and free sterol composition of free algal cells in batch culture. A shift in temperature from 25°C to 10°C led to an increase in the relative proportion of oleate and decrease in linoleate and parinate (18:4), together with a significant increase in the composition of ergostenol. Exposure to heavy metal ions led to an increase in oleate (with all three metals) and altered relative proportions of linoleate and parinate (changes being metal specific). Metal ion treatment also increased a22 desaturation of chondrillasterol. This characteristic lipid signature when S. capricornutum was exposed to heavy metal ions was significantly different from changes associated with other environmental factors. These changes in lipid composition upon heavy metal treatment were also observed during exposure of S. capricornuiwn to lower metal concentrations typically found in polluted environments. Studies of cells immobilised within alginate beads showed that gel confinement significantly affected the biochemistry and physiology of algal cells, with a reduction in growth rate and final cells numbers. Scanning electron microscopy demonstrated that growth was mainly limited to the bead periphery. Immobilisation altered the lipid of composition of cells as a consequence of alterations in membrane fluidity and membrane disruption. The Cu uptake from solution was greater in immobilised cells than free cells, thus gel confinement did not confer any protection to cells. The characteristic and significant changes within the lipid composition of free cells with Cu treatment were similarly observed in immobilised cells but were only apparent at 124 pM Cu. Thus lipid profiles, especially sterol composition of immobilised algal cells, may potentially be utilised as sensitive and novel indicators of heavy metal pollution in freshwater environments.

Despite improved knowledge and advanced treatments of high-grade gliomas, the overall survival rate of glioma patients remains low due to the recurrences and locations of the tumour. Evidence shows that the existence of a subpopulation of cells - cancer stem cells (CSCs) may be the major obstacle in treating gliomas. CD133 and nestin have been suggested as the markers of CSCs and natural stem cells. The primary focus of this study was to identify CD133+/nestin+ stem-like cells and discover their association with multidrug resistance (MDR) related genes, i.e. multiple drug resistance I (mdrl) gene and anti-apoptotic gene (bcl-2) in human glioma compared to normal brain tissues and cell lines. Glioma and normal astrocyte cell lines have been employed for CD133 isolating purposes to characterise the association with MDR related genotype and phenotype. The chemosensitivity of the isolated CD 133 population was investigated using chemosensitivity assay. Meanwhile, a serum deprivation method was established in this study to enrich and select CD 133+ CSCs in a glioma (GOS-3) cell line. As a secondary focus of this project, the possibility of immortalisation enzyme hTERT being a discriminative masker between normal and cancer brain stem cells and the transcriptional correlation between cd133 and bmi-lIc-myc oncogenes were investigated. For the first time, findings of the current study demonstrated that 1) there was an evident increase of CD133 gene expression in glioma compared to normal brain tissues where the latter expressed low levels of CD133, P-gp and Bcl-2 than glioma tissues, with an exception of nestin expression, 2) serum deprivation enriched CD133 expression and demonstrated a direct coexpression between CD133 and drug resistance in GOS-3 cells, 3) hTERT may not be a discriminative marker for normal and cancer brain stem cells, 4) although there was a strong transcriptional association between bmil and cmyc, there was an inverse transcriptional association between these genes and cd133 in serum deprived glioma cells, suggesting that bmil may not be essential for the maintenance of glioma stem cells, and 5) CD133+ glioma and normal brain cells showed a significantly high resistance towards chemotherapeutic drugs compared to the autologous CD133- cells. In conclusion, an improved understanding of molecules contributing to the maintenance of CSCs may lead to a combined treatment, targeting both CSCs and their protective MDR phenotypes leading eventually to attractive strategies for the treatment of gliomas.

In the mammal, anaesthetics are known to act via two distinct mechanisms, either increasing inhibition via GABAA receptors (eg. Na-thiopentone) or decreasing excitation via NIvIDA receptors (eg. ketamine). The aim of this thesis is to investigate the effects of both increased inhibition and decreased excitation at the synaptic level within an invertebrate model system, something which cannot readily be done in vertebrate systems. This was achieved by carrying out experiments using both the above mentioned anaesthetics on the whole animal, isolated brain and cultured neurons. In invertebrates it has been shown that GABA and Glutamate can be both excitatory and inhibitory, and injection of GABA into Lymnaea has been shown to result in behavioural changes in feeding, locomotion, escape reactions, male mating and respiration. Injection of Na-thiopentone into the whole animal was carried out in this investigation, in order to establish the anaesthetic response of the animal model to this barbiturate. The presence of gamma-aminobutyric acid (GABA) receptors has been demonstrated in a respiratory interneuron (RPeD1) both electrophysiologically and via molecular techniques, however inmiunostaining has proved negative in RPeD1 and follower cells VD2/3 (unidirectional excitatory synapse) and VD4 (mutual inhibitory synapse). This suggests that these neurons are not themselves GABAergic, although this investigation shows the responses of these neurons to bath and direct application of GABA. Na-thiopentone did not reliably anaesthetise Lymnaea upon injection into the sole of the foot, suggesting that Na-thiopentone binds to proteins within the snail, andlor has a low affininty for the GABAA receptor in Lymnaea. Other anaesthetic studies using propofol and ketaniine have also demonstrated a lack of anaesthetic response. RPeD1 hyperpolarised and became quiescent in response to the application of high concentrations of GABA (10 3-104M), however at lower doses (1O 8-1O 5M), no effect was observed (p < 0.05). Under these conditions simultaneous recordings from VD4 showed hyperpolarisation in response to the application of GABA, whereas VD2 and VD3 exhibited excitatory responses. Presynaptic picoinjection of GABA also resulted in hyperpolarisation and quiescence in RJeD1, but the simultaneous response in VD3 was not observed. Postsynaptic application of GABA directly to 'VD2, and VD4 however, resulted in responses similar to those seen in the whole brain. VD2 and 3 also receive input 2, which hyperpolarises RPeD1 and elicits an excitatory EPSP in VD2 and 3 as this is similar to the response observed in this experiment it is possible that the effects of input 2 on RPeD1 and VD2 & 3 are mediated by GABA. As RPeDI does not stain positively for GABA and hyperpolarises in response to the drug, it seems unlikely that the postsynaptie effects are due to presynaptic release of GABA. RPeD1 has been shown to form reciprocal synapses with VD4 both in vivo and in vitro. When perfused with GABA (lmJ'i4), both cells hyperpolarised reversibly. The postsynaptic response could be due to the action of GABA presynaptically inhibiting RPeDI, or directly on postsynaptic GABA receptors. However VD4 forms connections with other cells in the brain such as input 3 which may also have resulted in this inhibitory response. RPeD1 would however have received a simultaneous excitatory input from this interneuron. Attempts were made to establish the nature of the RPeD1JVD4 synapse in these experiments, but no synapses were evident. These experiments therefore confirm the presence of GABA receptors in RPeD1 and suggest theft presence in VD2, and VD4. This investigation confirms the findings of previous studies, that injection and bath perfusion of barbiturates does not lead to responses in Lymnaea comparable to that of the mammal. In addition to it's main target site, ketamine (a frequently used intravenous anaesthetic) has also been shown to act at cholinergic receptors. The effects of ketamine on learning and memory and apoptosis in the mammalian CNS are well recognised. Within the Lymnaea CNS, VD4 and LPeD1 form a unidirectional excitatory cholinergic synapse, and this was chosen to investigate the effects of ketamine on excitatory synaptic transmission, short term potentiation and synapse formation in the invertebrate animal model. Ketamine decreased synaptic transmission between VD4 and LPeD1 in a concentration dependent manner, but did not significantly affect short term synaptic plasticity (pc0.05). While neurite outgrowth remained extensive, actual sprouting was diminished by all doses of ketamine. Cells exhibited extensive veiling, which was not present in control cells. Percentage chemical synapse formation was reduced by all doses of ketamine, and in some cases inappropriate inhibitory chemical synapses were formed. Furthermore acute, clinically relevant levels of ketamine reduce excitatory cholinergic transmission between VD4 and LPeD1, but short term plasticity is unaffected. Nerve regeneration was seriously compromised, and formation of appropriate chemical synapses greatly reduced. This data has serious implications for the clinical - use of ketamine, particularly in pregnant women, children or critical care patients where nerve regeneration and synapse formation are of great importance and long term exposure common practice. In conclusion, this work supports that of other studies which have showed that invertebrates appear to be relatively insensitive to barbiturates, whereas ketamine appears to effect excitation in a manner similar to that in the mammal.

Antiulcer agents, notably inhibitors of gastric acid secretion, have been the most successful category of drugs to be discovered in recent years; and moreover, there are currently four such agents in the world list of top 25 best selling drugs. Histamine H2 antagonists have been the number one selling pharmaceutical product for more than a decade and inhibitors of the parietal cell HIC-ATPase, so called "proton pump inhibitors" (PPI), look set to continue this success. The proposed study was designed to establish the relative efficacy and mechanisms of action of three novel agents using both in vitro and in vivo models. The three compounds namely AG-1749 (Lansoprazole), PD-136450 and transforming growth factor alpha (TGF(x) were studied to evaluate their antisecretory and antiulccr activities. Lansoprazole, the second PPI to be developed for clinical use, is a non-competitive inhibitor of the H1C-ATPase and has recently been launched in a number of countries. PD-136450 is a competitive antagonist of central and peripheral cholecystokinin-B (CCK-B) receptors (gastrin receptor) and it under clinical development as an anxiolytic but which has actions on the stomach and pancreas. Anxiolytic drug is otherwise known as anti-anxiety drugs, which are used to treat anxiety disorders, like depression, panic disorders, phobias and many personality disorders. TOFu is a polypeptide growth factor, which acts at the EGF receptor and displays potent mitogenic and antisecretory activity. The initial study deals with the comparison of the three compounds with omeprazole and ranitidine in terms of their ability to inhibit acid secretion and their activity in a range of experimental ulcer models. Potency, duration of action and activity against a range of stimulants of acid secretion (histamine, pentagastrin and basal) was determined in anaesthetized rat models by establishing dose-response relationships. The compounds represent a spectrum of activities in as much as lansoprazole is a potent, long acting inhibitor, PD-136450 is an orally active but selective inhibitor, while TOFu has a very short duration and is only active after parenteral administration. In a view to find out the mechanism of action of these drugs on gastric acid secretion, isolated gastric glands from rabbits were employed as an in vitro technique using radiolabeled 14C-aminopyrine as a marker. The results show that lansoprazole was the most potent antisecretory agent compared to other two drugs. The second phase of the study deals with the activity of the three compounds against gastric ulcers induced by acid hypersecretion, indomethacin and stress. This study enabled us to assess the extent to which antisecretory activity per se compared with other actions such as wound healing (TGFa) or anxiolytic activity (PD-136450) contribute to ulcer healing. As other workers already established that prostaglandins and nitric oxide are involved in the cytoprotective activity, the present study investigated the influence of prostaglandin and nitric oxide by using indomethacin and L-NAME pretreatment on the cytoprotective activity of lansoprazole, PD-136450 and TGFcz. Moreover, the three drugs were tested for their activities on the mucus and bicarbonate production in the stomach. It was found that lansoprazole and TGFc increased the gastric mucus secretion while PD-136450 did not show any change. Moreover it was evidenced from this study that the protective activity of PD-136450 is associated with the influence of bicarbonate secretion from the pancreas. In conclusion, the results of this study have indicated that lansoprazole, PD- 136450 and TGFct are potent antisecretory and antiulcer agents which have great therapeutic importance.

Mature skeletal muscle fibres can be classified as type I, type IIa, type IIx or type IIb fibres according to the myosin heavy chain (MHC) isoform that they express. More broadly, type I fibres are classified as slow fibres and type IIa, IIx and IIb fibres as fast fibres. However, the phenotype of an adult skeletal muscle fibre is not fixed: it displays plasticity being capable of adapting to changing activity and loading levels by either transition towards a slower phenotype or transition towards a faster phenotype. Overall, the aims of these studies were to further investigate and define the signal transduction pathways implicated in the control of skeletal muscle fibre phenotype. The ability of a fast muscle to undergo a transition towards a slower phenotype in response to chronic low-frequency stimulation (CLFS) was assessed, via metabolic enzyme activity assays and NADH-TR staining, following blockade of the calcineurin signalling pathway. Metabolic enzyme assays and northern blots were employed to assess the changes in enzyme activities and MEC isoform expression levels following blockade of the calcineurin and ERK1/2 signalling pathways in primary cultures of rat myotubes. Differences in the levels of various signal transduction proteins/transcription factors between slow and fast muscle were investigated using western blotting. The nuclear translocation kinetics of NFAT and NF-κB in response to treatment with the calcium ionophore A23187 were investigated in L6 myotubes using immunocytochernistry. Calcineurin blockade using cyclosporin A failed to prevent a decrease in lactate dehydrogenase activity and an increase in NADH-TR staining intensity, both characteristics of a transition towards a slower phenotype, following CLFS of the fast rat tibialis anterior muscle. Blockade of the ERK1/2 pathway in primary cultures of rat myotubes using U0126 significantly decreased MHC Iβ mRNA levels and significantly increased MIHC IIx, MEC IIb and perinatal MHC mRNA levels. Calcineurin blockade significantly decreased MHC Iβ and embryonal mRNA levels and significantly increased MHC IIx mRNA levels. Calcineurin blockade also significantly increased the activities of lactate dehydrogenase and creatine kinase while ERK1/2 blockade significantly increased the activities of lactate dehydrogenase, creatine kinase, hexokinase, malate dehydrogenase and β-hydroxyacyl-CoA deydrogenase. ERK1/2 and NF-κB levels were found to be higher in slow muscle compared to fast muscle while calcineurin and p38α,β levels were higher in fast muscle compared to slow muscle. No nuclear translocation of NF-κB and only limited evidence for NFAT nuclear translocation was seen in L6 myotubes following treatment with A23187. Overall these studies further characterize the roles of the ERK1/2 and calcineurin pathways in the regulation of muscle phenotype suggesting that each pathway controls some, but not all, of the genes that are differentially expressed between slow and fast muscle fibres. Western blotting suggests further signal transduction protein/transcription factor targets, the functions of which may be explored in the future.

Shape and attitude of near-Earth objects directly affect the orbit propagation via drag and solar radiation pressure. Obtaining information beyond the object states (position and velocity) is integral to identifying an object. It also enables tracing origin and can improve the orbit accuracy. For objects that have a significant distance to the observer, only non-resolved imaging is available, which does not show any details of the object. So-called non-resolved light curve measurements, i.e. photometric measurements over time can be used to determined the shape of space objects using a two step inversion scheme. It follows the procedure to first determine the Extended Gaussian Image and then going through the shape reconstruction process to retrieve the closed shape even while measurement noise is present. Furthermore, it is also possible to generate high confidence candidates when follow-up observations are provided through a multi-hypotheses process.

The prevalence of social media in political campaigns are changing the face of politics in the United States and abroad. The rapid pace at which this change is occurring demands inquiry into the previously unexplored area of unconventional political campaign messaging practices on social media. Investigation of Donald Trump’s use of tweets as rhetorical strategy in the discursive space of Twitter during the 2016 U.S. presidential campaign revealed a bypass of traditional media and its source verification processes. This circumventing of mainstream media channels facilitated Trump’s deployment of an unchecked ‘broken system’ narrative alleging government corruption

and a rigged system. Trump’s tweet discourses tapped into existing feelings of disenfranchisement and disaffection felt by a self-identified politically marginalized segment of society. This study

investigates how social media use in political campaigns can serve as a public sphere for contestation of social and political norms. An interdisciplinary theoretical frame comprised of Feenberg’s critical theory of technology, McLuhan’s media ecology, Fraser’s counterpublic spheres, and Iser’s implied reader offer new understandings about the power of anti-establishment discourses and a hybrid discursive space to destabilize governing institutions and redefine social and political identities. Study of Trump’s tweets as rhetorical strategy granted insights into the social and political capacity of alternative truth to undermine the political process. Further, it uncovered the power of social media to awaken and leverage existing political identities for personal political gain.

Plantation forests are susceptible to many pests, which can reduce the quality and value of the wood products they source. Certain species of the fungal genus Mycosphaerella are a concern in eucalyptus plantations around the world. Mycosphaerella leaf disease (referred to as MLD from here in) can cause significant leaf necrosis, discolouration and defoliation. In Australia severe outbreaks of MLD have been observed in various eucalyptus plantations. The three aspects of MLD research targeted in this Thesis were factors influencing its atmospheric ascospore concentrations, the effect of its symptoms on leaf spectral properties, and the use of remote sensing to detect MLD’s symptom distribution and severity.

With the growing popularity of using smartphones in business environments, it is increasingly likely that phones will be the target of attacks and sources of evidence in cyber forensic investigations. It will often be important to identify who was using the phone at the time an incident occurred. This can be very difficult as phones are easily misplaced, borrowed, or stolen. Previous research has attempted to find ways to identify computer users based on behavioral analysis. Current research into user profiling requires highly invasive examinations of potentially sensitive user data that the user might not be comfortable with people inspecting or could be against company policy to store. This study developed user profiles based on changes in a mobile phone's underlying block structure. By examining where and when changes occur, a user profile can be developed that is comparable to more traditional intrusion detection models, but without the need to use invasive data sets. These profiles can then be used to determine user masquerading efforts or detect when a compromise has occurred. This study included 35 participants that used Samsung Galaxy S3s for three months. The results of the study show that this method has a high accuracy of classifying a phone's actual sessions correctly when using 2-class models. Results from the 1-class models were not as accurate, but the Sigmoid SVM was able to correctly classify actual user sessions from attack sessions.