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Animal pigment patterns are as diverse as they are beautiful. Characterised by their striking blue and golden stripes along the body tails and fins, the adult Danio rerio (zebrafish) has become a major model organism for the study of pigment patterns. The stripes are comprised of three different pigment producing cell types which selforganise over a period of three weeks into the adult stripe pattern. Over the past two decades, a multitude of observational, cell and genetic studies have determined numerous mechanisms involved in this self-organisation, yet, it has still been unclear whether or not these rules were sufficient to generate the pattern. To aid analysis of complex systems such as this, mathematical modelling has become a powerful assistive tool. By providing a theoretical framework, a mathematical model allows us to clearly articulate our hypotheses in a quantitative manner and then test these hypotheses. The goal of this thesis is to develop a mathematical model of zebrafish stripe formation which will be used both within this thesis and in the future, in conjunction with biological experimentation to elucidate the key mechanisms underlying zebrafish stripe formation. We will start by introducing the known mechanisms as determined from biological experiments, as well as introducing the findings and limitations of previous mathematical models of zebrafish stripe formation. Based on this knowledge, we will build our own comprehensive mathematical model of zebrafish stripe formation incorporating all the up-to-date biological information. As we will demonstrate, not only does this model quantitatively and qualitatively reproduce the wild-type striped pattern, but it can also reproduce many of the mutant patterns. Thus we show that the rules determined from the biology are, to at least a good approximation, sufficient for producing the striped patterns. Having validated our approach, we next use the model as a predictive tool to guide further investigation. For example, in the last chapter of the thesis, we will use the model alongside biological experimentation to explore the importance of growth during pattern metamorphosis in the context of both Danio rerio and its close relatives. Along the journey of this interdisciplinary study, we will develop new techniques across mathematics and biology that will aid this investigation. For example, in order to validate our mathematical models ability to generate wild-type zebrafish stripes, as well as other mutant patterns, we will develop a pair correlation function: a statistical tool used for quantifying spatial correlation. In order to compare our theoretical model with the biology, we will refine a method for anaesthetising and subsequently imaging juvenile fish during pattern development that minimises suffering. Therefore the outcomes of this thesis not only aids our understanding of pattern formation, but provides a framework for future investigations of its kind.

Pavlovian conditioning processes may be central to hedonic overeating. The following experiments were conducted to explore how learning shapes motivational and attentional processes that might enhance reactivity to food-related cues. A primary aim was to explore the efficacy of a novel, naturalistic appetitive conditioning procedure, first described by Blechert et al. (2016), for producing rapid conditioned responses in as little as a single conditioning trial. This novel paradigm was designed to mimic a real-life experience with a new food, from the initial sight, smell and touch, to consumption. Subjective measures of craving, expectancies and liking tapped in to explicit motivational processes, and an Emotional Blink of Attention (EBA) task, originally reported by Piech, Pastorino & Zald (2010), was used to explore implicit attentional processes. The degree of incentive salience acquired by newly learned cues was measured as the extent to which they captured attention in a rapid serial visual presentation task (RSVP), preventing accurate target detection in a phenomenon known as an attentional blink. Experiments 1 and 2 (Chapter 3) failed to show evidence for appetitive conditioning on explicit measures, which I suggest can be attributed to the relatively low reward value of the food item chosen for conditioning (marzipan). Findings presented in Chapters 4 – 7 found more convincing evidence that appetitive conditioning shapes motivational processing of newly learned food cues; after a single pairing, an edible object made from a highly rewarding foodstuff (chocolate) elicited cravings, expectancies for chocolate and was perceived as more highly pleasant than a visually similar plastic object. Experiment 4 (Chapter 5) demonstrated that additional trials did not enhance conditioning, supporting the view that single trial learning with hedonic food rewards is a powerful phenomenon. Furthermore, Chapter 6 demonstrated how this learning spreads to cues varying in their similarity to the original conditioned stimulus via generalisation. A consistent finding throughout Chapters 3-6 was that attentional processing was modulated by this naturalistic conditioning procedure, although not as originally predicted. After just one conditioning trial, both reinforced and non-reinforced cues captured attention more readily than neutral cues, suggesting salience acquisition independent of reward. Whilst Chapter 4 confirmed that reward-paired cues acquire greater salience than novel or familiar cues after a single exposure, it seems that the novelty has a synergistic influence over this process. I suggest that contextual novelty, in the form of the unusual conditioning procedure, promotes further learning and exploration of newly encountered stimuli, thus maximizing the possibility of acquiring reward. Chapter 7 presents a final experiment, which explored the neural correlates of appetitive conditioning in a single trial. Again, conditioning was evident based on subjective evaluations. Tentative evidence suggested a potential role for the right superior frontal gyrus in enhancing inhibitory control in response to passive viewing of cues signalling no reward. Brain activity in areas related to salience attribution was greater for a reward-paired cue presented briefly in an EBA paradigm. Although, evidence for reward-driven attentional capture was absent at a behavioural level. Overall, this thesis supports the utility of a novel naturalistic conditioning paradigm for studying appetitive conditioning processes in a single trial. Just one experience with a novel edible object transformed it into a highly desirable, craved cue. Potential applications of these findings for informing treatment and interventions for obesity and eating disorders, as well as methodological considerations and limitations are discussed in chapter 8.

Thirty years ago the self-storage industry in the UK was non-existent; now it is the biggest in Europe. Renting a self-storage unit is advertised as the solution to controlling clutter, a secure space for valuable objects and way to enable mobility. Its growth in size and popularity is thought to be symptomatic of wider material afflictions and shifts in Western society including overconsumption, an increase in divorce rates, an ageing population, increased mobility and 'generation rent'. Self-storage plays a significant role in routine domestic practices as well as distinct periods of transition (i.e. moving house), trajectories (i.e. growing up, growing older) and events (i.e. bereavement, divorce) that occur over the life course. The overall aim of this thesis has been to form an understanding of what self-storage units signify including, and besides, their storage function. Based on interviews and object elicitation at self-storage units with users in the UK, this thesis argues that our possessions, as they are sorted, packed, moved and stored, are integral aspects of our dwelling and mobility in the contemporary world. By bringing to light the narratives surrounding hidden objects stored in self-storage units, this thesis has shown that 'unpacking' this kind of materiality provides rich possibilities to understand and grasp the world beyond and displaced from people's immediacies. This thesis firmly situates self-storage use within a range of contextual forces: the categorisation, ordering and hierarchical place(ment) of matter in response to ideas of clutter, mess and excess; the containment of contingency and potential futures in the face of uncertainty; and the connection and consolidation of identities in light of mobility and changes across the life course. It adds new sets of ideas to engage with theories of consumption, home and identity, and demonstrates the importance of acknowledging stored materiality as a distinct, necessary and complex phase in biographies and geographies of objects, which has previously been underplayed in the material culture literature.

This thesis constitutes an investigation into the depiction of dreams in imagery accompanying the late-medieval manuscripts and printed editions of the Roman de la Rose. It reflects on the changing approaches to depicting dreams during the 250 years of the Rose’s popularity in central France, as well as discussing the historical theoretical understanding of the concept of dreams, and its expression in a specific Rose context. It examines the representation of dreams in a number of Rose manuscripts – in particular their prominent dreamer incipits – alongside other relevant miniatures of both a secular and religious nature. Furthermore, the alteration of trends for depicting the dream space in Rose manuscripts during the fifteenth century are also considered, as well as a case-study of the luxurious Valencia manuscript, which contains a variety of dream subjects. This is followed by a discussion of the methodology of manuscript production in the medieval period, gleaned from a number of extant Roses. This chapter underscores the important role played by artistic originality and intention in the processes of manuscript making – addressing the ‘artistic vision’ indicated in the title of this thesis. An outline of the printed editions of the Rose and their resurrection of earlier tropes of dream depiction is also included. Finally, the appendix contains a Catalogue of the Rose manuscripts studied in preparation for and throughout the production of the thesis.

Severe windstorms regularly inflict damage throughout Europe. This research examines a set of 31 midlatitude cyclones, investigating each in depth but encompassing a wide variety of such storms. The set is selected using the Storm Severity Index, and categorised using two methods. The first method is based on the relationship between the storm and the jet stream. Four groups emerge: storms that move along the edge of the jet; that cross the jet stream early; that cross later; or have a split jet. The second method is based on the Pressure Tendency Equation. This establishes whether horizontal temperature advection or diabatic processes dominate during storm development. These two approaches are linked: storms in the first two jet groups tend to be driven by horizontal temperature advection, and the other two groups by diabatic processes. This work then studies the storms’ forecast quality and spread using ECMWF data. It finds that storm intensity tends to be under-forecast, the forecast storms move too slowly and are too far south. Forecast quality improves and spread decreases earlier in storms that cross the jet early, compared to those that cross later, suggesting a link between jet interaction and forecast error. Storms where horizontal temperature advection dominates are on average less well forecast than their diabatic counterparts, but diabatically driven storms tend to have greater forecast spread. Finally, this study proposes metrics for storm-prone situations, examining the configuration of the atmosphere prior to the development of the storms. These describe a variety of key factors for cyclogenesis, such as baroclinicity, barotropicity and moist stability. Of the 31 storms, 29 are associated with a value greater than the 98th percentile of one or more metrics. There is a large overlap between storms where baroclinicity is strong and those where horizontal temperature advection dominates the deepening, confirming that the two approaches are dynamically linked. This relationship between the storms, the dynamics, and the metrics will allow future work to identify sources of uncertainty in modelling severe European windstorms.

In complex systems, it has been observed that the parts within the system are "loosely coupled". Loose coupling means that the parts of the system interact in some way, and as long as this interaction is maintained the parts can evolve independently. Detrimental evolutionary changes within one part of the system do not negatively affect other parts. Overall system functionality is maintained, leading to faster evolution. In swarm robotic systems there are multiple robots working together to achieve a shared goal. However it is not always obvious how to program the actions of the robots such that the desired aggregate behaviour emerges. One solution is to use a genetic algorithm to evolve robot controllers, this approach is called "Evolutionary Swarm Robotics". This thesis makes the case that swarm robotic systems are complex systems, and hypothesises that loose coupling between the robots in a swarm would lead to faster evolution. Robot swarms are investigated where robots describe environmental features to each other as part of a foraging task. Multiple descriptions can be used to describe a feature. The mappings between feature descriptions, and the signals used to express those descriptions, are manipulated. By doing this, the interactions between robots can change over time or stay the same. Results show that loose coupling leads to higher swarmfitnesses because it makes the communicated information easier to interpret. However there are some subtleties in its working. We also observe that if some of the information is not useful for completing the task, this negatively affects swarm fitness regardless of coupling. This problem can be mitigated by using loose coupling. This research has implications for the design of communication within robot swarms. Before evolution, it is difficult to know what information is relevant. This research shows that sharing unnecessary information between robots is detrimental to swarm fitness because the cost of interpreting information can be greater than the benefit gained from the information. Loose coupling can reduce, but not eliminate, the evolutionary cost of interpreting multiple pieces of information in exchange for slower message transmission.

This thesis examines the area of user-involvement in the development of computerised office information systems, with particular reference to gender relations and to initiatives in 'Human-Centred' systems design. it is based on a review of literature in computer science and in social science, and on case-study research. The thesis forms a contribution to the interdisciplinary work of the Human-Centred Office Systems Project, at Sheffield Polytechnic. Interdisciplinary research into information systems development is expanding, partly in response to evidence that many systems fail to meet their stated objectives. There is increasing emphasis on issues of "user relations', including user-involvement. In offices, as in other contexts, women tend to be defined as users or operators of technology; however, there has been little research into the constraints and opportunities women office workers face specifically in connection with information systems development. Previous projects within Human-Centred Systems research have been located in areas in which men predominate, such as printing and engineering. The thesis makes a contribution to new interdisciplinary research on information systems in two main respects. Firstly, the scope for clerical involvement is examined. It is argued that clerical skills and experience can form a strong basis for involvement in office systems design; in addition, managerial reliance on clerical skill and cooperation appear to increase, with the advent of on-line, integrated office systems. However, the case study research also illustrates the ways in which gendered associations can play a part in the definition of 'social' and 'technical' aspects of systems development, tending to marginalise clerical contributions. Secondly, therefore, the thesis examines the potential of Human-Centred systems development approaches to address gender inequalities in opportunities for user-involvement. Methods for establishing a Human-Centred approach in a local authority department are proposed; an assessment of their use, in a case-study context, exposes a weakness in the Human-Centred tradition in relation to management practices. In conclusion, specific proposals are formulated to support the creation of new links between organisational strategies on information technology and those on gender inequality.

Research has explored the relationship between posttraumatic growth (PTG) and communication trends. Yet, there is a gap in research regarding how positive declarations of desired outcomes can influence PTG and be applied in a therapeutic context. The purpose of this quantitative study was to examine if positive declarations of psychological growth facilitate PTG after trauma and impact levels of hope, anxiety, or depression. A small pilot study was conducted through six counseling sessions with participants (N = 16) divided into either the control (n = 8) or experimental group (n = 8). A novel Positive Communication Approach (PCA), distinguished by linguistic psychoeducation and use of positive declarations, was only implemented with the experimental group. Pretest-posttest data was collected using the SRGS-R, AHS, GAD-7, and PHQ-9 and analyzed by an analysis of covariance (ANCOVA). ANCOVA results indicated no significant difference between group level for each research question. However, cumulative scores on all four questionnaires were higher for the experimental group than the control group, with a more substantial change noted for PTG and hope. The differences between clinical and statistical findings may be attributed to the study’s small sample size. Findings support existing literature regarding communication and PTG while providing an empirical source of support for scripture. Furthermore, PCA may be an effective therapeutic intervention for facilitating PTG by cultivating hope and expectation.

It is the responsibility of mental health counselors to provide compassion for broken and hurting populations. For counselors, the continuous strain of empathizing with distressed clientele can often result in physical and emotional exhaustion known as compassion fatigue (Figley, 1995a). Although providing continuous compassion for others may contribute to negative experiences such as compassion fatigue, counselors can also experience positive outcomes from showing compassion towards clients, known as compassion satisfaction (Figley, 2002b). While risk factors to compassion fatigue have been widely explored among various occupations within the literature, less has been researched regarding moderating effects between compassion fatigue and compassion satisfaction, specifically among counselors. The purpose of this quantitative study is to assess the moderating effects of organizational culture and self-care practices between counselor compassion fatigue and compassion satisfaction, using regression analysis. Participants include licensed and pre-licensed counselors. As expected, compassion fatigue and compassion satisfaction were negatively correlated (r = -.367, p < .001). Data analysis results indicated that organizational culture and self-care practices did not have a significant moderating effect between compassion fatigue and compassion satisfaction. However, peer support, supervisory support, personal self-care, and professional self-care transmitted a significant positive effect on compassion satisfaction. Limitations for this study and implications for future research are presented.