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Coarse-grained modelling of DNA nanostructures allows their structural, mechanical and thermodynamic properties to be characterised. In this thesis, we illustrated how coarse-grained modelling combined with umbrella sampling can be applied to compute the free energy landscapes of large DNA nanostructures, and how these landscapes can be used to characterise the self-limiting assembly of DNA origamis. We first described the mechanical deformation of DNA nanotubes by computing their free energy landscapes using distance-based order parameters. We analysed the behaviour of the nanotubes under different levels of bending stress and compared their behaviour to the worm-like chain model, revealing two regimes of bending depending on the localisation of the bending stress. We further demonstrated the computation of free energy landscapes on a mechanically bistable DNA origami. Interestingly, the landscape computed from simulations only shows one minimum, which is different from the bistable landscape inferred from experimental observations of ensembles of origamis. We decomposed the landscape into one component for each joint in the origami and discovered that only one such component showed bistability, which was masked by the other components and resulted in an overall landscape with a single minimum. We also examined the self-limiting assembly of DNA origamis. We studied a DNA origami that assembles with stress propagation through displacement accumulation. We characterised the structural properties of the origami monomer and its polymers, as well as the free energy landscapes of the monomer associated with the main stress accumulation mechanisms. We parameterised a simple one-dimensional model using the landscapes and ran Monte Carlo simulations to estimate the stress free energy of polymers as a function of their lengths. As an extension, we explored other possible DNA origami designs that could undergo self-limiting assembly through mechanisms other than displacement accumulation. In particular, we evaluated the use of curvature and twist accumulation to propagate stress in assemblies of DNA origamis.

Three problems that are linked by way of motivation are addressed in this work. In the first part of the thesis, we study the generalised Langevin equation for simulated annealing with the underlying goal of improving continuous-time dynamics for the problem of global optimisation of nonconvex functions. The main result in this part is on the convergence to the global optimum, which is shown using techniques from hypocoercivity given suitable assumptions on the nonconvex function. Alongside, we investigate numerically the problem of parameter tuning in the continuous-time equation. In the second part of the thesis, this last problem is addressed rigorously for the underdamped Langevin dynamics. In particular, a systematic procedure for finding the optimal friction matrix in the sampling problem is presented. We give an expression for the gradient of the asymptotic variance in terms of solutions to Poisson equations and present a working algorithm for approximating its value. Lastly, regularity of an associated semigroup, twice differentiable-in-space solutions to the Kolmogorov equation and weak numerical convergence rates of order one are shown for a class of stochastic differential equations with superlinearly growing, non-globally monotone coefficients. In the relation to the previous part, the results allow the use of Poisson equations for variations of Langevin dynamics not permissible before.

In face of global population ageing, the World Health Organization (WHO) launched the Age-friendly Movement in 2006 and developed the WHO age-friendly framework that is being widely adopted around the world. Although there is an extensive body of literature on age-friendly development following the WHO movement, limited discussion was on the process at the neighbourhood level, particularly in relation to the interplay of different stakeholders. To fill in this research gap, this study adopted a neo-institutionalist lens with elements of street-level bureaucracy in comparing the process of how age-friendliness is being enacted at the neighbourhood scale in Manchester and Hong Kong, through a comparative case study approach. This is the one of the first truly international comparisons on age-friendly cities of western and non-western contexts. Data was collected through document analysis, in-depth interviews and participatory observation. The findings of this thesis document the process of age-friendliness at the neighbourhood level, with rich detail on the interplay of the different stakeholders involved. The major contribution of these findings is bringing a new perspective in understanding age-friendly processes by introducing the role of street-level bureaucrats (SLB), who are the determining agent in shaping how age-friendliness is being enacted at the neighbourhood level. Moreover, the findings in both cases also suggest an interdependent relationship between the processes at the city and neighbourhood levels. This thesis also suggests that the role of academics can be strengthened through a collaborative partnership of different stakeholders in developing age-friendliness at the community level. Finally, by contrasting the two case studies, it is shown that the ways of interpreting age-friendliness among different stakeholders vary place by place. This thesis hence concludes by suggesting age-friendliness as a fluid concept that should be embraced with a flexible mindset.

This thesis attempts to identify what the barriers to building a trusted police service in China and India are through answering the questions: How has economic modernisation impacted upon policing? To what extent are the two police forces trusted by its citizens? Do the police carry out their duties in a fair and unbiased fashion? What do police corruption/malpractices look like and why does it persist? And what are the influencing factors in decision-making at the moments-of-truth? There is very limited research into the Chinese Police generally and even less on factors affecting organisational culture, practices, and decision making. There is no comparative study between the Chinese and Indian Police. This thesis found that the Chinese Police are held in higher esteem than the Indian Police by their respective citizenry. Both the Chinese and Indian police use stereotypes and are biased against certain section of society in the way they carry out their duties and that corruption and malpractices are tolerated and engrained in its culture but is subtler in China than in India. However, one surprised finding is that India is more at risk of the rule by man than China, even though India is said to be the world's largest democracy grounded on the principles of the rule of law.

We consider several random walk related problems in this thesis. In the first part, we study a Markov chain on R₊ x S, where R₊ is the non-negative real numbers and S is a finite set, in which when the R₊-coordinate is large, the S-coordinate of the process is approximately Markov with stationary distribution πi on S. Denoting by μi(x) the mean drift of the R₊-coordinate of the process at (x,i) Ε R₊ x S, we give an exhaustive recurrence classification in the case where Σiπiμi(x) → 0, which is the critical regime for the recurrence-transience phase transition. If μi(x) → 0 for all i, it is natural to study the Lamperti case where μi(x) = O(1/x); in that case the recurrence classification is known, but we prove new results on existence and non-existence of moments of return times. If μi(x) → di for di ≠0 for at least some i, then it is natural to study the generalized Lamperti case where μi(x) = di + O(1/x). By exploiting a transformation which maps the generalized Lamperti case to the Lamperti case, we obtain a recurrence classification and an existence of moments result for the former. The generalized Lamperti case is seen to be more subtle, as the recurrence classification depends on correlation terms between the two coordinates of the process. In the second part of the thesis, for a random walk Sn on R^d we study the asymptotic behaviour of the associated centre of mass process Gn = n⁻¹Σ^n i=1 Si. For lattice distributions we give conditions for a local limit theorem to hold. We prove that if the increments of the walk have zero mean and finite second moment, Gn is recurrent if d=1 and transient if d≥2. In the transient case we show that Gn has diffusive rate of escape. These results extend work of Grill, who considered simple symmetric random walk. We also give a class of random walks with symmetric heavy-tailed increments for which Gn is transient in d=1.

In Romantic studies, Romanticism is regarded as a reaction against modernity, or more accurately, a self-critique of modernity. There have been critical debates over the nature of the preoccupation of the Romantics with the past and the natural world, whether such concern is an illustration of the reactionary tendency of Romanticism, or an aesthetic innovation of the Romantics. This study tries to approach this problem from the perspective of space. It draws from the spatial theory of Henri Lefebvre, discussed in the Production of Space, in which Lefebvre conceives a spatial history of modernity, and sees Romanticism as the cultural movement that took place at the threshold of the formation of abstract space. The poetry of three British Romantic writers, William Wordsworth, S. T. Coleridge and Joanna Baillie, is examined. This study analyses how the writers’ thinking and poetry writing are interactive with the formation of social space during the Romantic period. Their poetry embodies the lived experience of the time. The writers show an awareness of the performative aspect of poetry, that poetry is a kind of linguistic creation instead of mere representation, which can be used to appropriate the lived space of reality. This awareness is particular to these Romantic writers because their poetic tactics are socially contextualized. Poetry is their method, as well as manner of life, for confronting the unprecedented social changes brought by modernity. By using Merleau-Ponty’s phenomenology, an examination of the significance of the body and perception in Romantic poetry is also employed to show how, through the use of performative poetic language, the writers re-create their lived space so as to counter the dominance of abstract space.

Research into applying finite volume methods to problems in solid mechanics is presented. The investigation has been motivated by the idea that a high-fidelity aeroelastic simulation can be made possible by extending the finite volume methods already implemented in many existing computational fluid dynamics solvers to solid mechanics. A detailed study and survey of applicable methods have been conducted to identify suitable candidates for a three-dimensional time-accurate large-deformation solid mechanics solver. A vertex-centred and a cell-centred solver were initially implemented. Upon comparison, the cell-centred solver appeared to be computationally more efficient despite suffering from a numerical issue. From this analysis, an improved formulation was subsequently developed for the cell-centred solver. In addition, a robust method for numerical gradient evaluation has been developed and incorporated to minimise errors associated with skewed cells or poorly supported cells at domain boundary. The method is based upon the Green-Gauss method, but takes advantage of a secondary numerical gradient to improve overall accuracy and reliability . The improved cell-centred solver has been shown to be accurate, robust and suitable for large deformations in a non-linear validation case against NASTRAN. High computational efficiency has also been demonstrated in OpenMP parallelisation and convergence acceleration via multigrid. The multigrid implementation has been made possible through incorporating a dual-time implicit scheme into the solver.

This study was an attempt to assist Muslim societies in articulating indigenous solutions to the myriad of political challenges confronting them. Continuously facing intellectual and ethical alternatives to their own convictions and values, these rapidly changing societies are looking for pragmatic solutions that do not necessarily compromise their own principles, values and ideals. Specifically pertaining to the political realm, many Muslim polities grapple with the reconciliation of modernity and tradition. This process of reconciliation often leads to ideological and, consequently, political instability. This study focuses on an analysis of political culture for understanding ideological and political instability in Pakistan. It begins with a thorough overview of the literature on political culture and locates constant references to the 'core', 'enduring cultural component or 'stock of knowledge' in a society that accounts for national variations in political culture. However, what those descriptive labels precisely consist of and amount to was left vague, ambiguous and undefined. Therefore, this study proceeded to define that 'enduring cultural component, in regards to Muslim polities, and labelled it as the ’foundational’ aspect of Islamic political culture. More clearly the 'foundational' is representative of those metaphysical aspects of permanence in Islamic political culture and consists of Muslim societies' deeply cherished political ideals. Yet, this articulation is only the initial sphere of inquiry required to understand the complexity of political culture in Muslim polities. Specifically, understanding political culture in Muslim polities involves three spheres of inquiry: 'foundational', 'contextual' and 'individual.’ Those three spheres of inquiry are engaged in an ongoing triangular relationship. In other words, this interplay involves the ՝foundational political principles, thoughts and ideas - ՝ the ideals’; the ‘contextual’ in which those political ideals find depth, meaning and expression, as in Pakistan – ‘the reaľ; and, the ‘individual’ by the method and manner that political leadership chooses to interact with both the 'foundational' and contextual. The differing method and manner in which political leaders in Pakistan - the 'individual’ sphere of inquiry, choose to interact with the 'foundational' produces three variant political cultures: 'traditionalisť, 'secularist and 'revivalist. Amongst these variant political culture types, both the 'traditionalist' and 'secularist method of interaction are unable to achieve equilibrium, as the 'revivalist, between the spheres of inquiry. As a result, they both contribute towards ideological and political instability. On the other hand, the 'revivalist' method of interaction between the three spheres of inquiry produces a balance with the belief that the principle endures but its application is dependent on space-time.

Pyoverdins are siderophores which chelate with ferric ions forming a ligand complex. Pyoverdins are excreted from bacteria such as Pseudomonas, for example, Pseudomonas fluorescens, when grown in iron-deficient conditions, to scavenge for iron. Although, different species of Pseudomonas produce different pyoverdins with various constituents in their amino acid chains, they all share a common chromophore structure within the various natural siderophores. The possible biosynthesis of the pyoverdins chromophore is discussed. Herein a biomimetic synthesis of a model of the chromophore unit based on an oxidative cyclisation pathway was carried [out].

Congenital cataract is a rare disorder but is a priority of Vision 2020, the international programme for the elimination of avoidable blindness, reflecting its treatment potential and the consequences for the child and family if left untreated. As the aetiology of congenital cataract is unknown in the majority of cases with only a minority being preventable, informing secondary and tertiary approaches to prevent visual impairment is currently essential. The quality of life of children with congenital cataract has not previously been reported. This study was a unique opportunity to engage parents and children in the assessment of their quality of life, an important outcome. Equally, data are limited on the impact of amblyopia treatment on the psychological wellbeing of the child with congenital cataract and their families. The British Congenital Cataract Study (BCCS) cohort comprises a nationally representative group of children who at the time of the present study, have been under management for at least 6 years after diagnosis. 61% of children with bilateral cataracts achieved an acuity of at least 6/18: commonly considered the vision level at which children can be educated at mainstream schools with minimum extra help. The worst median visual acuity (6/48) was recorded in the cataractous eyes of children with unilateral cataract who underwent surgery, suggesting that despite intervention in these children, the outcome is still poor. Concordance with occlusion is the most important predictor of visual acuity of children with unilateral cataracts. Earlier surgery and concordance with occlusion are associated with better visual acuity and poorer acuity was associated with the presence of a severe cataract and other medical conditions in children with bilateral cataracts. The incidence of postoperative open angle glaucoma was 5.25 cases/100 eyes operated/year. Early age at detection is the most important factor associated with the development of glaucoma after congenital cataract surgery. The majority of parents found occlusion difficult and almost a third thought their child's behaviour had worsened. Furthermore, a third of the parents thought that the relationship with their child had worsened as a result of occlusion. Despite this, no association was found between occlusion concordance and the child's or parental experience of occlusion and the majority of parents never worried the patches were harmful. The quality of life scores of children with congenital cataract in the present study were comparable to those reported by children with childhood cancers and rheumatological disorders. This study's findings should inform future parents of children with congenital cataract especially those with unilateral cataract and have implications for resource allocation in terms of schooling and additional help. The findings also emphasise the importance of early detection to enable early surgery and the importance of occlusion to prevent amblyopia. Identification of underlying causes of difficulties with occlusion may initiate changing emphasis on the management of children with congenital cataract. Postoperative open angle glaucoma may be the price of successful screening programmes to ensure early detection and treatment of congenital cataract to mitigate against amblyopia. Further work is required to delineate precisely the optimal timing of surgery to balance the benefits of early intervention with potential risks. The finding that the quality of life of children with congenital cataract is comparable with more debilitating and life threatening disorders is unexpected and has implications for ophthalmologists regarding how they view the impact of congenital cataract on the HRQOL of these children.

This thesis aims to address the research gap of understanding the relationship between "creativity" and "job-related motivators" in Hong Kong Chinese hotel employees. The Psychometric approach to measure creativity was adopted, and specifically Byrd's model (1971) was used as the instrument to measure creativity. Risk taking and Creativity are the two factors in Byrd's model. Kovach's (1980) ten job-related motivators were adopted as the measurement of work, which includes both intrinsic motivators and extrinsic motivators. Moos' (1986) Work Environment Scale was adopted as the instrument to measure organisational climate. This instrument has three dimensions, the relationship dimension, the personal growth dimension, and the system maintenance and change dimension. The sample consists of 983 hotel employees, and the data were gathered using the questionnaire method. The data analysis proves that there is a relationship between creativity and job-related motivators (r = 0.311) with a high significance level at 0.000. However, there is no significant difference found for this relationship in the eight different organisational climates, High vs. Low organisational climate and various innovative indexes. Two demographic variables, i. e. "Education level (r = 0.469) and "Level of Job" (r = 0.444) were found to exert a significant difference over the relationship between creativity and job-related motivators. The study also discovered there is a relationship between creativity and organisational climate (r = 0.339) with high significance level. Similarly, no significant difference existed in the eight sub-sample organisational climates. A number of 2 way MANOVA tests were conducted and significant differences were found which justified further ANOVA and post hoc tests. In each dimension (creativity, job-related motivators, organisational climate), several interaction effects were found in various demographic factors. The author developed a See-Saw model to explain the relationship between creativity and job-related motivators. Like the see-saw in every child's playground, both sides (creativity and job-related motivators) of the rod of the see-saw can be independent variables, and they can both exert a force on each other. Risk-taking was found to be placed on the far left side, while Intrinsic Motivators was found to be placed on the far right side. The author recommends six C's for motivating creativity in the hotel industry in Hong Kong. They are: 1. ) Creating a macro culture by education, 2. ) Commitment from top management, 3. ) Congratulating success by reward and recognition, 4. ) Courage - risk taking, 5. ) Change - willing to accept new things and 6. ) Communication - exchanges of opinions for incubating creative ideas. To conclude, this research satisfies both etic (universal) and emit (cultural specific) objectives. The etic approach proved that creativity is found in Chinese culture, and there is a relationship between creativity and job-related motivators. However, there was no significant difference by different organisational climates in the Hong Kong Chinese culture (emit approach). National Chinese culture may have a more influential impact over this relationship.

In this thesis, the author presents a numerical and experimental study of the application of active constrained layer damping to a clamped-clamped plate. Piezoelectric actuators with modal controllers are used to improve the performance of vibration suppression from the passive constrained layer damping treatment. Surface damping treatments are often effective at suppressing higher frequency vibrations in thin-walled structures such as beams, plates and shells. However, the effective suppression of lower frequency modes usually requires the additional of an active vibration control scheme to augment the passive treatment. Advances in the technologies associated with so-called smart materials are dramatically reducing the cost, weight and complexity of active structural control and make it feasible to consider active schemes in an increasing number of applications. Specifically, a passive constrained layer damping treatment is enhanced with an active scheme employing a piezoceramic (PZT) patch as the actuator. Starting with an established finite element formulation it is shown how model updating and model reduction are required to produce a low-order state-space model which can be used as the basis for active control. The effectiveness of the formulation is then demonstrated in a numerical study. Finally, in the description of the experimental study it is shown how modes in the frequency range from 0 to 600 Hz are effectively suppressed: the two lowest modes (bending and torsional) through active control, the higher modes (around ten in number) by the passive constrained damping layer. The study'S original contribution lies in the experimental demonstration that given a sufficiently accurate model of the plate and passive constrained damping layer, together with a suitable active feedback control algorithm, spillover effects are not significant even when using a single sensor and single actuator. The experimental traces show, in some instances, minor effects due to spillover. However, it can be concluded that the presence of the passive layer introduces sufficient damping into the residual modes to avoid any major problems when using only the minimum amount of active control hardware.

The possibility of developing a satisfactory serological test applicable to seroepidemiological studies of brugian and bancroftian filariasis was investigated. The cat-Brugla uahungi model was used. The relative sensitivities of the indirect fluorescent antibody test (IFAT), counter- immunoclectrophoresis (CISP) and ensyme-linked immunosorbent assay (ELISA), using crude or purified somatic, and metabolic antigens of various developmental stages of six different human and animal filarioids, for the detection of antibodies in sera were compared. Homologous antigens were always better than heterologous antigens in sensitivity. Metabolic antigens seemed to be more species-specific. A rise in antibody level was observed after chemotherapy. IFAT using B. pahanrj and Wuchereria bancroiti infective larvae as antigens were the most sensitive tests for feline (89% positivity), and human brugian (96%) and bancroftian (100%) filariasis respectively. In ELISA, fractions 1 and 2 of the partially purified antigen of B. nahangi adults seemed to be more specific for bancroftian and brugian filariasis respectively than the crude antigen. ELISA and IFAT were found useful in the seroepidemiological studies of human filariasis in New Guinea, Trinidad, the Seychelles Islands and Egypt. ELISA and CIEP wore used to detect circulating worm antigen in sera and urine, using rabbit antisera to B. pahangi antigen. Studies with phosphoglucomutese isoenzymes of B. pahangi adult worms suggested that these isoenzymes could be the source of specific antigen for serological tests. The histopathology of the lungs, liver, spleen, kidneys, infected lymph nodes and lymphatics of B. pahangi-infected cats was studied. A higher percentage of glomeruli in kidneys from 71 infected cats showed histological lesions when compared to the uninfected controls. Fluorescence studies demonstrated the presence of IgG» worm antigens and complement deposits in the glomeruli of kidneys from infected cats. 40% of infected cats had proteinuria by Albustix test. The presence of circulating immune complexes in sera from infected cats and humans with brugian and bancroftian filariasis was studied by C1q- and conglutinin-binding assays.