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The morphogenetic movements in epithelial sheets seen during organogenesis are driven in part by changes in cell shape, which in turn depend on changes in the cytoskeleton. In this thesis I used the formation of the salivary glands in the Drosophila embryo, which are formed by coordinated apical constriction and invagination of a polarised epithelial placode, as a model to understand these changes. The role of microtubules (MTs) during morphogenetic processes such as this are not well understood. In order to ascertain their role in successful tubulogenesis I looked at both stable and newly polymerized MTs within the salivary gland placode. Apical constriction is accompanied by the loss of a centrosomal apically localised MT network and the appearance of a longitudinal acentrosomal MT network. In parallel, MTs become increasingly more stable, starting from the apical surface and spreading more basally, leading to stable MT bundles that appear nucleated and anchored near the apical surface independent of centrosomes. Disrupting the MTs specifically in the salivary gland placode using the MT-severing protein Spastin results in defects in apical constriction, and at later stages tube lumen defects. Wild type cells generate an apical medial actomyosin meshwork that likely drives apical constriction. MT ends present at the apical surface colocalise with apical medial actomyosin, and cells lacking MTs fail to maintain apical medial actomyosin. This indicates crosstalk between the MT and actomyosin cytoskeleton during apical constriction and tissue bending. The cytolinker protein Short Stop (Shot) has previously been shown to be able to link the actin and MT cytoskeleton. Shot rearranges concomitant with the MT cytoskeleton and colocalises with both with the tips of MT bundles and apical medial actin. Further to Shot, the formin Diaphanous regulates both actin and microtubules in morphogenesis, and was also found to localize to MT tips at the apical surface. Overexpression of constitutively active Diaphanous results in precocious invagination of the salivary gland. Overall this suggests a role for acentrosomal MT bundles in maintaining an apical actomyosin meshwork for successful apical constriction and subsequent tubulogenesis. Cytoskeletal crosstalk may be mediated by the cytolinker Shot and the formin Diaphanous.

A growing field of research has evolved around the design and synthesis of a variety of porous metal-organic framework (MOF) materials. Some of the most promising areas for which these materials are potentially useful candidates include gas-separation, heterogeneous catalysis, and gas-storage, and all of these applications involve placing the MOF under pressure. There is clearly a need to understand the structural response of MOFs to applied pressure. Nevertheless, hitherto there are very few published investigations dedicated to determining the behaviour of porous hybrid materials under pressure. Through the use of high-pressure single-crystal X-ray diffraction studies, a series of MOF materials have been studied. Here we present the effect of pressure on a series of MOFs. In chapter 2, the effect of pressure on the prototypical MOF called MOF-5 was studied experimentally from ambient pressure to 3.2 GPa. Here, application of pressure was driven by the hydrostatic medium being forced into the pores of the MOF, which altered the mechanical properties of MOF-5, in particular, medium inclusion delayed the onset of amorphization. Complementary computational analysis was also performed to elucidate further the effect of medium inclusion on compressive behaviour. Detailed structural data was also collected as a function of pressure on the MOF Cu-btc. Application of pressure caused solvent to be squeezed into the pores (like MOF-5) until a phase transition occurred, driven by the sudden compression and expansion of equatorial and axial Cu–O bonds. High-pressure post-synthetic modification of a MOF is reported for the first time. On application of pressure of 0.2 GPa to the Cu-based MOF called STAM-1, a ligand exchange reaction takes place resulting in a change in pore size, shape, and hydrophilicity of the resulting pores. Here, we also demonstrate the ability to force hydrophilic molecules into hydrophobic pores using pressure, counteracting the hydrophobic effect. A high-pressure combined experimental and computational study has been carried to probe the effect of pressure on ‘breathing’ mechanisms in a zeolitic imidazolate framework (or ZIF) called ZIF-8. The penetration of guest molecules and the accommodation of pressure are shown to be inextricably linked to the rotation of methylimidazolate groups in the structure. Finally, the application of pressure to the MOF Sc₂BDC₃ and the nitro functionalized derivative Sc₂(NO₂-BDC)₃ was also studied. Here, the effect of chemical modification of the organic ligand, whilst maintaining framework topology, has been investigated as it pertains to compressibility. Directionality of compression is observed and this is rationalized with respect to the framework topology and medium inclusion/exclusion.

The increasing demands placed on conventional methods of liquid atomization, in terms of spray quality, now mean that there is a need for a new, disruptive, liquid atomization technology which can rapidly improve spray performance to meet the growing sophistication required of modern liquid spray systems. This thesis details an investigation into the mode of action of a liquid atomization system (pMISTe) which shows promise to be able to provide this disruptive new spray technology. Influenced by the defence mechanism of the bombardier beetle, this atomization method produces a large amount of volumetric shear in a body of liquid, by inducing a flash evaporation of a proportion of the total liquid mass in an enclosed chamber. The flash evaporation is created firstly by heating the liquid far above its saturation temperature at an ambient external pressure - in a chamber cavity sealed by an electronically controlled ejection valve. This valve is released very rapidly, causing the liquid in the chamber to suddenly `see' the ambient external pressure. It is this sudden exposure of a superheated liquid to the low external ambient pressure that drives the flash evaporation and the atomisation. The atomization system was investigated using a staged experimental method, including a mixture of Taguchi Design of Experiment (DoE) and full factorial techniques. From these investigations the main characteristics of the mode of action of the system were identified. These were that, in general, increases in chamber liquid temperature caused decreasing average droplet size, and that increases in refill flow rate caused increasing droplet size; due to the primary flash evaporation mechanism. In addition more complex secondary behaviours, attributed to the fluid dynamic properties of the system, were discovered. The performance of the system is also discussed with reference to its suitability for a range of spray applications

The thesis discusses the subject of time as dealt with in the writings of Edwin Muir, exploring the ways in which his poetry, novels, and critical writings articulate a range of perspectives regarding the nature of time and its relation to human experience. Following the adaptation of ideas through Muir’s career, a trajectory is traced from his early writings in which time is seen as a destructive power antithetical to life through to the celebration of mortality in his late writings. Integral to this development was his persistent interrogation of the relationship between time and eternity. Identifying the important role of Muir’s autobiographical method, this thesis begins by exploring his desire to obtain an objective view of human life by establishing a critical distance in his writings between the subject being presented and the imagination that presents it. To this end, his creative writings often incorporate myths, biblical allegories, heraldic symbolism, and surreal abstractions to present archetypal or timeless events and situations. In doing so, Muir is seen drawing on an array of literary and philosophical influences, many of which relate to his adolescence and formative adulthood in Glasgow. His rural childhood in Orkney and his early contact with Presbyterian and Evangelical Christianity made a lasting impression on his imagination with the resultant preoccupation with Eden and the Fall being dominant features of his poetry. Often dealt with in an abstract way in his poetry, Eden is frequently associated with his childhood on Wyre in his autobiographical writings, with the Fall, in Muir’s theorizing, forming the moment at which time becomes of relevance to humanity. Critically under-appreciated as ephemera and juvenilia, Muir’s earliest prose and poetry in The New Age magazine between 1913 and 1923 convey a strong sense of his desire to engage with the popular debates of the day regarding contemporary literary and social matters. For this reason, a significant amount of space has been given in this thesis to allow these writings to be re-evaluated; not just as portents of his later work, but also as important contributions to the vibrant journal and magazine culture of the period. Offering substantive detail to sketch the relevant biographical context, the essays, critical monographs and volumes of poetry are discussed chronologically and with reference to each other to allow the development of Muir’s ideas to be seen as an organic evolution rather than as a series of philosophical epiphanies. However, the significance of Muir’s reconciliation to Christianity in 1939 is highlighted as the single most important creative breakthrough of his mature adulthood. The extensive range of Muir’s critiques of Scottish and European culture, and his essays on the relationship between literature and society more generally, underline his position as a modernist writer immersed in the affairs of his time. Through detailing Muir’s creative and philosophical struggles with himself and modernity (which he felt he had fallen into through a time-accident) he is seen repeatedly reaffirming his commitment to exploring the nature of time and its meaning for human society.

In order for computers to interact with and understand the visual world, they must be equipped with reasoning systems that include high–level quantities such as objects, actions, and scenes. This thesis is concerned with extracting such representations of the world from visual input. The first part of this thesis describes an approach to scene understanding in which texture characteristics of the visual world are used to infer scene categories. We show that in the context of a moving camera, it is common to observe images containing very few individually salient image regions, yet overall texture structure often allows our system to derive powerful contextual cues about the environment. Our approach builds on ideas from texture recognition, and we show that our algorithm out–performs the well–known Gist descriptor on several classification tasks. In the second part of this thesis we we are interested in scene understanding in the context of multiple calibrated views of a scene, as might be obtained from a Structure–from–Motion or Simultaneous Localization and Mapping (SLAM) system. Though such systems are capable of localizing the camera robustly and efficiently, the maps produced are typically sparse point-clouds that are difficult to interpret and of little use for higher–level reasoning tasks such as scene understanding or human-machine interaction. In this thesis we begin to address this deficiency, presenting progress towards modeling scenes using semantically meaningful primitives such as floor, wall, and ceiling planes. To this end we adopt the indoor Manhattan representation, which was recently proposed for single–view reconstruction. This thesis presents the first in–depth description and analysis of this model in the literature. We describe a probabilistic model relating photometric features, stereo photo–consistencies, and 3D point clouds to Manhattan scene structure in a Bayesian framework. We then present a fast dynamic programming algorithm that solves exact MAP inference in this model in time linear in image size. We show detailed comparisons with the state–of–the art in both the single– and multiple–view contexts. Finally, we present a framework for learning within the indoor Manhattan hypothesis class. Our system is capable of extrapolating from labelled training examples to predict scene structure for unseen images. We cast learning as a structured prediction problem and show how to optimize with respect to two realistic loss functions. We present experiments in which we learn to recover scene structure from both single and multiple views — from the perspective of our learning algorithm these problems differ only by a change of feature space. This work constitutes one of the most complicated output spaces (in terms of internal constraints) yet considered within a structure prediction framework.

Studies of complex systems and agent-based models often focus on the relationship between microscopic behaviour and phenomena on a macroscopic level. Such models have applications in sociology, biology and economics. Here we study specific models in evolutionary game theory and game learning, analysing the differences between deterministic, population-level descriptions and stochastic, individual-level descriptions. We also examine the relationships between individual actions and global features in data from a financial market. Attempts to explain the emergence of altruism commonly use evolutionary game theory. Here, stochastic models can exhibit continued oscillations when the equivalent deterministic dynamics approach a fixed point. We classify the power spectra of such stochastic oscillations using an expansion of the master equation in the inverse system size. We find that the choice of update rule can have significant effects on the frequency and amplitude of these fluctuations.In light of recent experimental setups of social dilemmas to test the applicability of evolutionary theories to human players, we show that noise-induced oscillations can also be found in models of multiplayer game learning. We again perform an expansion in the noise strength to classify these oscillations analytically. We examine the effect that the parameters of the model can have on these fluctuations in both well-mixed and networked setups. We also use financial time series from the Spanish Stock Market to quantify features of the actions of individual trading firms. Examining how trades impact prices we find that the variety of individual behaviours cannot be inferred from that of the market. We test the applicability of an existing model by Bouchaud et al for reconstructing the response of the price to trades over time and show that it does not extend to describing any particular firm.

Eye movements are essential to the way that primates and humans investigate the visual world. These eye movements depend upon the task being performed, and thus cannot be accounted for by bottom-up features, as in the model of Itti et al. (1998). Here we seek to investigate the role of task information in the redirection of gaze, by starting with an existing biologically based model of the primate oculomotor system (Chambers. 2(07). We integrate a revised version of the model with a new model of object recognition, produced using inspiration from the HMAX model of Riesenhuber and Poggio (1999), combined with a computational advantageous and biologically accurate method of visual attention. This approach of utilising and combining existing models where possible we describe as 'systems integration'. The full model reproduces a wealth of experimental evidence, in- cluding the effect of set size on reaction time for different difficulty visual search tasks (Treisman and Gelade, 1980), and additionally on saccadic latency and fixation duration for difficult visual search tasks (Motter and Belky, 1998a), as well as the effect of onset on search behavior found by Yantis and Jonides (1996). Novel explanations for these behaviours are suggested, under an overarching framework, which can only be provided because of 'the biological realism present in this model. We then extend the model with additional competencies, using an enhanced 'systems integration' approach. This involves including engineered phenomenological components that replicate neural competencies. This extended model is embodied in robotic hardware - thereby improving the veracity of the world-model interaction. The extended competencies include reward based associative learning, and habituation to repeated task irrelevant distraction. This model is exercised with an ethological experiment, and provides predictions regarding the nature of the mechanisms behind reward based as- sociative learning - notably, the model predicts that reversal learning is important when the reward associated with objects changes.

The purpose of the thesis is to examine the International Community’s (IC) responses to post-conflict at the turn of the twenty-first century and in a period of transition. The thesis will establish whether there are any standard models for the IC’s engagement in post-conflict and if so whether these models are gradually ‘evolutionary’ or subject to radical change. The thesis will situate the IC’s response within the existing academic models and will encompass a review of these models so as to establish whether recent post-conflict interventions can be adequately defined by them. The thesis will also define a typology of post-conflict so as to establish whether the existing definitions are ‘fit for purpose’. The thesis will make use of a substantial body of empirical evidence which was gathered by the author during a period of fourteen years spent in the Western Balkans. It will in consequence address the issue of ‘observation’ in the research design and conclusion. The thesis will use this corpus of evidence gathered to illuminate the points raised during the thesis and to establish whether the changes in the typology of the IC’s response to post-conflict in the Western Balkans were specific to those particular missions or whether they represented a longer-term change in approach by the IC. As part of this changing approach to post-conflict, the thesis will also examine the role of the European Union (EU) and question the role which the EU, only one amongst many regional and sub-regional organisations, has ascribed to itself in the IC’s management of post-conflict.

This thesis examines representation, a key but relatively neglected issue in contemporary democratic theory, through an ethnography of engagements between indigenous representatives and the state in the Brazilian health sector, which has pioneered the adoption of participatory and deliberative “new democratic spaces”. Part I, “Locating Representation”, argues that contemporary debates that privilege the creation of new democratic spaces as a response to the shortcomings of representative democracy ignore the importance of these spaces' own issues of representation. The section goes on to outline the context for the research (which was conducted at the national level and in two sites in the Amazon region), describing the process of action research and multi-sited ethnography. The main body of the thesis makes the case for developing a situated understanding of three dimensions of representation: the representation of issues for political debate and policy deliberation; the representation of different social groups in relation to the state; and the representation of the process of democratic engagement itself. Part II, “Representing Health” examines the contrasting understandings of health expressed by two groups of policymakers and bureaucrats – those managing Brazil's national health system, the SUS, and those responsible for the Indigenous Health Subsystem of the SUS – and by shamanic practitioners and other indigenous health experts. Part III, “Representing People” examines the discourses and mediation roles of indigenous representatives operating in new democratic spaces, and the contrasting representation strategies of two regional indigenous movement organisations who took on management of outsourced services within the Indigenous Health Subsystem. Part IV, “Representing Democracy”, examines three cases of indigenous representatives' engagement with the state through new democratic spaces in the health sector, and concludes by analysing the potential for new approaches to representation to contribute both to the political inclusion of marginalised minorities and to the broader reinvigoration of democracy.

Chapter four discusses the crystal structures of the monomers and in particular the factors affecting the formation of inclusion compounds.

This thesis demonstrates why it is important to engage with and carry out psychogeographical research in psychology and why a psychogeographical turn to place is needed. I begin with a critique of mainstream experimental psychological attitudinal and behavioural responses to the events of September 11 2001. I draw on responses from psychology, mass media theory and situationism. Elements of discursive theory will be drawn on to demonstrate the importance of going beyond an analysis of words to study images and places. News reports in British newspapers of the World Trade Center attacks will be critically evaluated in relation to the day afterwards and then in explaining how the events were commemorated one and five years on.