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Glioblastoma multiforme (GBM) is the most malignant adult brain tumour. A subpopulation of cells, termed glioblastoma stem cells (GSCs), possesses similar phenotypic characteristics to normal neural stem cells (NSCs) and may drive tumorigenesis. GSCs frequently express many essential neurodevelopmental transcription factors (TFs) at high levels. Of particular note are SOX2 and SOX9 genes, which are master regulatory TFs in the forebrain development with reprogramming activity that are essential for GSC self-renewal. Here we explored a set of newly identified small-molecule compounds that was shortlisted following phenotypic screening for loss of SOX2 in GSCs. We showed that a subset of these hits operates via the ubiquitin-proteasome system (UPS), revealing a potentially new pathway controlling SOX2 and SOX9 protein turnover. We demonstrated that these compounds likely act through a class of enzymes called deubiquitylases (DUBs). The lead compound 1035 was validated across a range of different patient models using two orthogonal reporter lines. We also confirmed that the endogenous protein was degraded via a proteasomal mediated pathway. We explored the selectivity of effects on cell viability and proliferation using an independent panel of non-GBM cell lines, including human umbilical vein endothelial cells, fibroblasts, non-tumour pericyte-like cells as well as human pluripotent stem cells (hPSCs)-derived neuroepithelial. The compound appeared selective, yet had some degree of off-target toxicities at higher doses. However, we did notice a strikingly significant positive correlation between the effect on GSC proliferation and SOX2/SOX9 expression levels. USP36, USP39 and USP42 were determined as potential DUB targets to which 1035 might bind, based on their restricted subcellular localisation to the nuclear/nucleolar compartments, in addition to lower SOX2/SOX9 abundance after individual knockdown. Concurrent deletion of these USPs was also able to phenocopy the compound effects, with diminished cell viability as well as proliferative arrest, alongside a robust SOX2 and SOX9 protein decline. Next, four structural analogues of 1035 were significantly less effective in overall at reducing endogenous SOX2 and SOX9, implying that the presence of a chiral carbon atom or/and methyl group at the asymmetrical carbon position is/are absolutely critical to retain compound activity. Individually purified R or S enantiomer was unexpectedly less potent than the original 1035, but this was restored in a racemic mixture, consistent with both enantiomers possibly operating together with a concerted synergism. The right-handed stereoisomer R mainly facilitated SOX2 and SOX9 protein degradation via USP42 (and maybe USP36 to a limited extent); meanwhile the left-handed stereoisomer S gave rise to broad cytotoxicity via nucleolar disruption pathway in a non-cell-selective manner. The structure-activity relationship can then be applied for future medicinal chemistry optimisation to improve lead compound potency and on-target specificity, whilst minimising the non-selective killing impact on normal human cells.

This thesis combines the multidisciplinary fields of literary, film, music, and cultural studies in a timely re-positioning and re-evaluation of the current scholarship on Shakespeare film adaptations. It considers various aspects of the soundtrack from a range of sound films, and includes discussions of non-Anglophone adaptations. By challenging the traditional audio-centric hierarchy prominent in both film studies and human perception, 1 demonstrate the auditory dimension’s significant contributions in facilitating stage-to-screen transitions, and seek to decentralise the ‘word as image’ preoccupation currently dominating the discourse on cinematic Shakespeares. Chapter 1 examines the non-musical sound effects employed in a number of films, primarily to support an adaptation’s ’updated’ setting, and to lend verisimilitude to cinematic battle sequences. Focusing on the manifestations of Western 'art music’, Chapter 2 discusses the cinematic and cultural effects of original film ’scores* and classical music citations. Chapter 3, by contrast, evaluates insertions of popular music and covers, which both provide adaptations with an additional level of accessibility. Chapter 4 departs from Anglophone films, and turns Its critical attention to Asian films and their soundtracks in order to engage with current debates about Shakespeare’s status and efficacy on the global-local spectrum. Returning to the play-texts, Chapter 5 assesses the filmic functions of both the early modem and film-original musical settings of Shakespeare's songs. Finally, Chapter 6 demonstrates a method of analysing oft-overlooked cinematic silences, thus concluding this groundbreaking thesis on a particularly polemical note.

Dynamical systems as models of complex biological systems are powerful tools that have been used to study problems in biology. This dissertation first discusses a problem in the theory of dynamical systems on the definition of topological entropy. Then dynamical systems are applied in two different fields of biology: proliferation of monolayer epithelia and the spread of infections and information.The notion of topological entropy is a measure of the complexity of a dynamical system. It can be conceptualized in terms of the number of forward trajectories that are distinguishable at resolution ε within T time units. It can then be formally defined as a limit of a limit superior that involves either covering numbers, or separation numbers, or spanning numbers. If covering numbers are used, the limit superior reduces to a limit. While it has been generally believed that the latter may not necessarily be the case when the definition is based on separation or spanning numbers, no actual counterexamples appear to have been previously known. Here we fill this gap in the literature byconstructing such counterexamples.We then use dynamical systems to study the proliferation of epithelia. Epithelia are sheets of tightly adherent cells that line both internal and external surfaces in metazoans (multicellular animals). Mathematically, a cell in an epithelial tissue can be modeled as a k-sided polygon. Empirically studied distributions of the proportions of k-sided cells in epithelia show remarkable similarities in a wide range of evolutionarily distant organisms. Multiple types of mathematical models have been proposed to explain this phenomenon. Among the most parsimonious of such models are topological ones that take into account only the number of sides of a given cell and the neighborhood relation between cells. The model studied here is a refinement of a previously published such model (Patel et al., PLoS Comput. Biol., 2009). While using the same modeling framework as that paper, we introduce additional options for the choice of the endpoints of the cleavage plane in the simulated development of epithelial tissues. Some of these options appear to be more biologically realistic approximations of known mechanisms that influence the cleavage plane orientation. A comparative analysis of comprehensive simulations for relevant combinations of both previously studied and our newly designed options is reported here. We compared the outcomes with the empirical distributions of the same five organisms as in (Patel et al., 2009), Drosophila (fruit fly), Hydra (closely related to jellyfish), Xenopus (clawed frog), Cucumber, and Anagallis (a flowering plant). We found that combinations of some of our new options consistently gave better fits with each of these data sets than combinations of previously studied options for choosing the cleavage plane.We also examine ODE models of epidemic spreading with a preventive behavioral response that is triggered by awareness of the infection. Previous research on such models has mostly focused on the impact of the response on the initial growth of an outbreak and the existence and location of endemic equilibria. Here we study the question whether this type of response is sufficient to prevent future flare-ups from low endemic levels if awareness is assumed to decay over time. In the ODE context, such flare-ups would translate into sustained oscillations with significant amplitudes. Our results show that such oscillations are ruled out in Susceptible-Aware-Infectious-Susceptible models with a single compartment of aware hosts, but can occur if we consider two distinct compartments of aware hosts who differ in their willingness to alert other susceptible hosts.

The signalling lipid ceramide has been implicated in the pathogenesis of obesity-related insulin resistance. Ceramide is synthesized by a family of six ceramide synthases in mammals (CerS1-6), each of which preferentially utilises fatty acids of particular acyl chain length (C14-C28). In skeletal muscle (SkM), C18 ceramide, which is synthesized almost exclusively by ceramide synthase 1 (CerS1), has been suggested to mediate systemic insulin resistance in obese humans and rodent models. Therefore, targeted reduction of SkM C18 ceramide may improve detrimental metabolic outcomes induced by a high fat diet (HFD). This thesis describes the characterisation of a new, selective inhibitor of CerS1, P053. P053 inhibits CerS1 with an IC50 of 0.5 micromolar and selectively reduced C18 ceramide in cultured cells. Lipidomic profiling revealed that P053 administration specifically reduced C18 ceramide levels in SkM of mice fed with standard chow or HFD for 4-6 weeks. The reduction of SkM C18 ceramide was coupled to a compensatory increase in C24 ceramides, which are synthesized by CerS2, and loss of triacylglycerols. No other complex lipid species were affected by P053 treatment. At the physiological level, P053 impeded fat deposition induced by a HFD. Despite its effect on adiposity, P053 treatment had no effect on glucose tolerance and insulin sensitivity, assessed by glucose tolerance test and hyperinsulinemic-euglycemic clamps. Unexpectedly, prolonged CerS1 inhibition with P053 improved mitochondrial oxidative capacity in SkM. This effect was associated with significant increases in mitochondrial respiratory chain complex levels, increased activity of TCA cycle and β-oxidation enzymes, and increased mitochondrial respiratory capacity in SkM. Enhanced mitochondrial metabolism may therefore underlie the reduced lipid accretion in mice treated with P053. A significant positive correlation between SkM C18 ceramide and body adiposity was identified. In contrast, SkM C24 ceramides were inversely correlated with adiposity. Thus, P053 may reduce adiposity both directly by reducing SkM C18 ceramide and indirectly through the associated increase in C24 ceramides. In conclusion, we have generated the first selective CerS1 inhibitor. Results from this thesis revealed a potential new role for CerS1 as an endogenous inhibitor of mitochondrial oxidative function in SkM and regulator of whole-body adiposity.

The innovation of P2P technology in digital world challenges the present copyright institutions and retailers. People are declined to look for the protection from the traditional law in digital circumstance. As the trend of extending copyright protection term across the world, most intellectual property institutions implement new technologies to deal with such situation. This paper uses a panel of country-level data to investigate the extent to which this is a consequence of the extension of copyright protection. Utilizing the economic model, the analysis suggests that the economic effects of implementing DRM technology are generally negative, albeit uncertain. The available evidence suggests the implementation of the technologies like DRM (Digital Rights Management) in copyright protection is likely to have little significant effects on music sales. The key factors that may have impact on music sales include Population, GDP, Internet Penetration and Domestic Piracy. Confronting the impact of new technological innovation, there might be temporarily declination in music industry and confusion in digital property protection system, but a balancing situation will finally be reached.