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The COVID-19 pandemic has exposed deep health inequalities between more economically developed and less economically developed countries: both in terms of diagnostics and vaccinations. Robust and low-cost point of care devices are needed to ease these diagnostic inequalities. Current point of care lateral flow immunoassays, utilise proteins, such as antibodies, to sense for analytes. This is epitomised by the malaria rapid diagnostic test and archetypal home pregnancy test. Glycans are emerging as alternative detection units due to their fundamental role in biological signalling and recognition events. Furthermore, the increased robustness, low-cost and synthetic possibilities offered by glycan-based systems, especially glycosylated polymers, make them a promising alternative to antibody-based biosensing and diagnostic systems. Chapter 1 discusses the current use of protein-based lateral flow and flow-through devices; their advantages and disadvantages versus non-point of care techniques, and the potential of glycan-based lateral flow devices. The concepts introduced in Chapter 1 are then applied in Chapters 2 through 5. Chapter 2 demonstrates the use of glycosylated polymer-coated nanoparticles, produced by controlled radical polymerisation techniques for the sensitive, label-free detection of lectins in lateral flow and flow-through. The systems produced use only glycans, not antibodies, to provide recognition - a "lateral flow glyco-assay." The lessons learned in Chapter 2 are applied in Chapter 3 to probe the glycan-binding of the SARS-COV-2 spike protein in a "flow-through glyco-assay" and target a pseudovirus mimic of the target coronavirus in a lateral flow glyco-assay. Chapter 4 builds on Chapters 2 and 3, applying the fledgling glyco-assay technology to the "real-world" by sensing for the SARS-COV-2 virus in patient samples, alongside exploring the robustness of the devices themselves. Having explored the concept of glycosylated polymer-coated nanoparticles in lateral flow and flow-through setups; Chapter 5 changes focus and explores the use of polymeric anchors for the design of all-polymer ("vegan") lateral flow and flow-through devices. This work completely removes proteins as either detecting units or anchors from lateral flow for the first time. Chapters 6 and 7 explore more fundamental Chemistry than the previous chapters. Chapter 6 considers the use of the Mannich reaction to produce monosaccharides with amine functionality at C2, ideal for polymer conjugation, while maintaining hydroxyl functionality at C2. Although unsuccessful with the reagents used, the chapter highlights a potential avenue of future chemical exploration in novel glycan synthesis. Chapter 7 pulls together the x-ray photoelectron analysis data and spectra collected across a range of studies, including data collected in previous chapters, and considers if x-ray photoelectron spectroscopy can be used to determine relative grafting density in glycosylated polymer-coated nanoparticle systems. In summary, the key components of the emerging technology of lateral flow glycoassays are introduced, interrogated and investigated. The prototype devices tested against model proteins, viral proteins and patient samples, are found to show specificities and sensitivities that rival lateral flow immunoassay systems. The understanding developed in this thesis could pave the way to the first generation of lateral flow glyco-assays that are low-cost, stable in a wide range of conditions, and able to target a wide range of analytes and diseases.

Adenoviruses are a diverse virus family, infecting a range of animal hosts. The human adenoviruses comprise over 100 types, divided into seven species, A-G. Adenoviruses are clinically important as both engineered therapeutic vectors and pathogens. Adenoviruses are non-membrane bound viruses with double stranded DNA genomes, making them amenable to genetic manipulation and manufacturing at scale. This makes them attractive candidates as therapeutic vectors, currently under development as gene therapy vectors, viral vaccines, and oncolytic viruses. Adenovirus based vectors are in clinical trials for the prevention and treatment of diseases as diverse as Ebola infection and cancer, but are hindered by pre-existing antiviral immunity, leading to neutralisation of the virotherapy before it can have its therapeutic effects, and off-target tissue infections resulting in reduced delivery of therapeutic vector to the site of need. Many natural adenovirus infections do not require medical intervention as they are easily neutralised by the hosts immune system, though they can result in serious disease. Predominantly, this is a concern for immunocompromised patients. However, some types can cause symptoms including gastroenteritis, epidemic keratoconjunctivitis (EKC), and potentially fatal acute respiratory distress syndrome, in healthy adults. Species D adenoviruses are especially diverse, accounting for more than 50% of total adenovirus diversity and many instances of disease, including outbreaks of EKC. They can also be attractive as a basis for therapeutic viruses due to low rates of seroprevelance in the population and favourable immunogenicity profiles. However, little is known about most members of this species or the mechanisms which can make them either pathogenic or therapeutically useful. The work presented herein seeks to better understand how species D adenoviruses infect cells. We therefore investigate their fiber proteins, which mediate primary cell surface receptor binding. We identify previously unknown adenovirus receptor interactions and examine these results in the context of developing new therapeutic adenovirus vectors.

This thesis addresses a significant research gap in critical research on forced eviction. It attempts to shift focus from the experiences of the evicted, examined in previous studies, to the work of evictors and eviction enforcement. It asks how the ‘tools, technologies, strategies, and tactics’ of forced eviction develop and are implemented in England and Wales. Using qualitative interviews centred around a case study of a city in the North of England to examine the ‘everyday’ form of evictions, this thesis looks at the work of a Rent Arrears Recovery Team on the ‘Benford’ housing estate in the city, and the working lives of County Court Bailiffs at the local court as they work in the context of a national ‘housing crisis’. Interviews with third party organizations and a High Court Enforcement firm, video footage, and online accounts of large-scale evictions provided by a wide range of sources from social movements are used to explore the ‘exceptional’ forms of displacement that emerge on a national scale. This research shows that Eviction enforcement actors and specialists have to employ forms of coercion which exist on a continuum between the ‘emotional’ and the ‘physical’; these practices are underpinned by ‘intuitive’ tactics built through individual and personal histories and the historical context in which evictions take place. These strategies and tactics of eviction are shaped by the resistance of the evicted, and the development of the disciplinary institutions of eviction happens in response to this resistance, which sets the pace for the development of the capacity of the state and economy to displace. This points to a need for more work critiquing the disciplinary institutions of forced eviction, and the global economy of eviction enforcement.

Spin transfer in magnetic multilayers offers the possibility of a new generation of ultra-fast, low-power spintronic devices. New ways to control the resonance frequency and damping in ultrathin films are actively sought, fuelling study of the precessional dynamics and interaction mechanisms in such samples. One effect that has come under particular scrutiny in recent years is the spin-transfer torque, wherein a flow of spins entering a ferromagnet exerts a torque on the magnetisation, inducing precession. A flow of spin angular momentum is usually generated through a spin-polarised electrical current, but a promising alternative is the pure spin current emitted by a ferromagnet undergoing ferromagnetic resonance (FMR). This allows spins to be transferred without a net charge flow. The physics of the generation, transmission and absorption of pure spin currents is a developing field, and holds great promise for both industrial applications and as a means to study fundamental physical phenomena in exotic materials. This thesis presents an investigation into the magnetodynamics of ferromagnetic thin films and heterostructures grown by molecular beam epitaxy and studied using vector-network analyser ferromagnetic resonance (VNA-FMR), x-ray magnetic circular dichroism, vibrating sample magnetometry and x-ray detected ferromagnetic resonance (XFMR). Particular attention is paid to the anisotropy of damping processes that occur in thin films, and the different coupling mechanisms that can exist across non-magnetic spacer layers in spin valves and magnetic tunnel junctions. It is first shown that the static and dynamic magnetic properties of thin Fe films can be effectively tailored by dilute doping with Dy impurities, which introduces a sizeable anisotropy of Gilbert damping. The mechanism underlying this effect is discussed, as is the concurrent modification of the spin and orbital contributions to the magnetic moment. The focus then turns to magnetodynamics of ferromagnetic films coupled across a nonmagnetic spacer layer, examining how different materials permit different interactions. First, an insulating MgO layer is used to separate the FM layers; it is found that this attenuates a spin current in under 1~nm, but permits a static interaction for at least 2 nm. XFMR measurements are used to ascertain the different contributions of the two interactions, and shed light on their interplay. Next, the same techniques are applied to spin valves with a spacer layer of the topological insulator (TI) Bi2Se3. TIs are the subject of much attention in the physics community, as they hold the potential for dissipationless transport, extremely high spin-orbit torques, and a host of novel physical effects. Here, their ability to absorb and transmit a pure spin current is studied, testing their suitability for incorporation into existing device schemata. VNA-FMR measurements confirm that the TI functions as an efficient angular momentum sink. XFMR measurements, however, demonstrate the presence of a weak interaction between the two ferromagnets, able to persist up to at least 8~nm, and possibly mediated by the topological surface state. Finally, the angle-dependence of spin pumping through a Cr barrier is examined, finding that a strong anisotropy of spin pumping from the source layer can be induced by an angular dependence of the total Gilbert damping parameter in the spin sink layer. VNA-FMR measurements show that anisotropy is suppressed above the spin diffusion length in Cr, which is found to be 8 nm, and is independent of static exchange coupling in the spin valve. XFMR results confirm induced precession in the spin sink layer, with isotropic static exchange and an anisotropic dynamic exchange. Taken together, these studies provide an insight not only into the magnetisation dynamics of thin films (and ways to modify them) but a demonstration of the power of ferromagnetic resonance techniques, and their applicability across materials and concepts. The results offer valuable information on the transmission and absorption of spin currents by different materials, and several mechanisms by which enhanced spin torques and angular control of damping may be realized for next-generation spintronic devices.

The Asian Summer Monsoon generates intense seasonal precipitation across India, China and Indochina, comprising Earth’s largest monsoonal climate regime, and this vital component of the global energy and water cycles directly impacts the world’s most populous regions. Accurate palaeomonsoon reconstructions are required to investigate natural climate variability beyond the coverage of instrumental records and inform predictions of future monsoon trends. Stable oxygen isotope ratios (δ18O) are an important proxy for hydroclimate variability and stalagmite δ18O is widely used to investigate East Asian palaeoclimate, typically interpreted as a semi-quantitative measure of precipitation amount. However, recent studies suggest δ18O instead reflects multiple hydroclimatic processes, warranting a detailed understanding of precipitation and proxy δ18O systematics. This thesis (i) presents a quantitative Lagrangian study of atmospheric moisture transport and precipitation across central and eastern China, a continental region affected by the East Asian Summer Monsoon (EASM); (ii) investigates the hydroclimatic drivers of precipitation δ18O variability at Wanxiang Cave, an important site for palaeomonsoon reconstruction located near to the northerly EASM limit; (iii) evaluates the extent to which seasonal- to decadal-scale proxy δ18O variability reflects terrestrial moisture fluxes by constructing a pseudoproxy record for Wanxiang. Present-day precipitation across monsoonal China is primarily derived from the northern Indian Ocean and recycled intensely over the East Asian continent; Pacific Ocean moisture export peaks during winter. A geographically variable isotopic source effect is apparent in present-day mean monthly precipitation δ18O data. Wanxiang Cave precipitation δ18O variability during AD 2001-2002 is successfully reproduced by a recently-developed Lagrangian model which simulates air masses’ isotopic evolution along three-dimensional atmospheric trajectories, though winter values are ~2 ‰ over-depleted. Contributions of Tibetan Plateau- and free troposphere-derived moisture are identified as synoptic-scale isotopic depletion processes. Overall, land-derived moisture causes isotopic enrichment during summer, thus moderating depletion due to strengthened EASM circulation or increased precipitation amount. As such, periods of elevated summer surface temperatures may attenuate the seasonal EASM signal in precipitation and proxy δ18O. An idealised Rayleigh-type isotope model is unable to capture these effects accurately, emphasising the importance of regional moisture fluxes. A pseudoproxy record, driven by terrestrial moisture fluxes, replicates seasonal- to decadal-scale stalagmite δ18O variability at Wanxiang. The work presented in this thesis offers new insights into the influence of atmospheric moisture transport dynamics on precipitation and proxy δ18O variability across central and eastern China. This constitutes an important advancement in our ability to use δ18O to reconstruct past climate variability quantitatively in the EASM region.

This thesis is concerned with the wear of machinery during the rice milling process. Two machines have been studied in detail (which combined constitute “milling”). Background literature has been studied and further added to such that machine improvements can be made relating to both capacity and component wear life. The first part of the work undertaken considers material properties of rice grains in their various forms and machine components with which contact is made. Dimension measurements and SEM imagery have highlighted the organic nature of rice grains as an abrasive, and observations of the change in properties from pre to post process made. Mass change, grain profiles, coefficient of friction, grain hardness and compressive strength have all been measured. Wear observations of husking and polishing components has revealed similarities with known wear mechanisms. Microscopy and profilometry have shown the areas which are susceptible to increased wear rates whilst measurement of scratch angles has illustrated the motion of grains through the polisher. Small scale testing has been a key part of the research due to the impractically high capacity of full scale machines. Husking tests have established that the shear stress required to achieve a given husked ratio is constant suggesting that a harder rubber with the same coefficient of friction as a softer rubber will husk more efficiently. Fast capture camera footage of husking experiments has shown that grains rotate between the rubber counterfaces before husking which effectively creates a region of high pressure at either end of the grain. It has also revealed that grains maintain their initial contact with the slow roller whilst sliding against the fast roller once husked. Probable mechanisms for this effect have been determined and experiments have been conducted showing that the uneven wear created by the effect could be minimised by axial vibration of the slow roller. Small scale polishing experiments have been used to reveal the locations of the highest wear (through paint test) which have a pattern consistent with an uneven fill by the grains entering the polishing chamber or a resonance of the screens caused by cage spacing. High wear was noted at inlet thought to be a result of rapid scattering of grains on entry from the feed screw. Pressure sensitive paper has been used to determine contact pressure profiles for various stages and conditions in the polishing chamber and laser vibrometry has been used to observe the effect of loading on machine vibration. Computer simulations have been developed to simulate grain flow and have shown good compatibility with the physical experiments. This leads to the potential to use such methods for future machine design. Finally, this thesis covers the potential for further work along with how the work is best suited for industrial implementation.