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Abstract Wolfiporia cocos, a versatile fungus acclaimed for its nutritional and therapeutic benefits in Traditional Chinese Medicine, holds immense potential for pharmaceutical and industrial applications. In this study, we aimed to optimize liquid fermentation techniques and culture medium composition to maximize mycelial biomass (MB) yield, pachymic acid (PA) concentration, and overall PA production. Additionally, we investigated the molecular basis of our findings by quantifying the expression levels of genes associated with PA and MB biosynthesis using quantitative real-time polymerase chain reaction. Under the optimized fermentation conditions, significant results were achieved, with maximum MB reaching 6.68 g l−1, PA content peaking at 1.25 mg g−1, and a total PA yield of 4.76 g l−1. Notably, among the four examined genes, squalene monooxygenase, exhibited enhanced expression at 0.06 ratio under the optimized conditions. Furthermore, within the realm of carbohydrate-active enzymes, the glycoside hydrolases 16 family displayed elevated expression levels at 21 ratios, particularly during MB production. This study enhances understanding of genetic mechanism governing MB and PA production in W. cocos, highlighting the roles of squalene monooxygenase and glycoside hydrolases 16 carbohydrate-active enzymes.

Halide perovskites are the leading candidates for next-generation, low-cost optoelectronics with power conversion efficiencies well above 25%. However, operational stability remains a key challenge. Although there is an understanding that the microscale and nanoscale play a consequential role in determining the macroscopic performance and stability, significant gaps remain in the mechanistic understanding of degradation processes at the nanoscale and the mechanisms for stability in cation-alloyed systems. Nanoscale hexagonal phase impurities have been identified as problematic for operational stability, leading to both performance losses and morphological degradation. However, it is still unclear at what stage these phase impurities originate. Understanding this better is critical in order to mitigate the harmful effects of these phase impurities on performance and operational stability. Cation alloying is a commonly used technique in the field to mitigate these hexagonal phase impurities, although not without its challenges. In this thesis study, the nanoscale structural landscape of key halide perovskite compositions is studied. By taking snapshots of the perovskite at different states of the annealing process, the impact of phase impurities on device performance is characterised. Thereon, the mechanism by which composition dictates photostability in FA-rich perovskite absorber layers is studied. It is demonstrated that the composition impacts the degree of octahedral tilt, which is essential to restricting the transition to hexagonal phase impurities. Additionally, it is demonstrated that while a judicious mix of A-site cations can be used to stabilise the photoactive black phase of halide perovskites, it is challenging to achieve this homogeneously over large areas, necessitating a search for alternative or complementary approaches to stabilise perovskite via octahedral tilt. Using scanning electron diffraction (SED) studies, the spacegroup of additive-stabilised-CsPbI3 is demonstrated to be a low symmetry tilted γ-phase. Furthermore, using SED, the nanoscale structural landscape of mixed-phase CsPbI3 absorber layers is studied and it is demonstrated that both narrow-bandgap γ-phase and wide-bandgap δ-phase co-exist at the nanoscale, enabling stable and bright white-light emission. Overall, this thesis provides insights into the role of nanoscale structure in dictating the properties and behaviour of halide perovskites and offers rational guidelines for their optimisation and use in optoelectronic devices. Additionally, it is demonstrated that SED is a powerful tool for studying these materials at the atomic scale, allowing for the detailed characterisation of their structures and properties.

This thesis comprises three independent papers on applied microeconomics. The first chapter studies the impact of primary care provider mergers on quality in England. The second chapter investigates the effect of price dispersion on consumer search behavior, drawing evidence from the retail gasoline market in Greece. The final chapter builds on the second, studying the asymmetric price adjustment and the impact of market competition on the asymmetric price adjustment. The details of the three papers are summarized below: The Effects of General Practice Mergers on Quality in England The primary care market has witnessed a growing trend of provider consolidation through mergers and acquisitions, yet the implications of this concentration remain uncertain. This study addresses this gap by providing the first empirical evidence on the effects of provider mergers on quality using evidence from the English primary care market. By analyzing all provider mergers from 2014 to 2018, I find predominantly negative effects of mergers on quality. Clinical quality does not change at best, and patient satisfaction decreases dramatically. Notably, the impact on quality varies based on the size of the general practices involved. Mergers between large general practices show a detrimental impact on quality, while mergers between small general practices may yield quality benefits. Additionally, there is no difference in the quality impact between mergers involving parties in the same geographical market and those in different markets. An exploration of the mechanism reveals that mismanagement, rather than changes in market concentration, drives the observed decline in quality following mergers. The Effect of Competition and Price Dispersion on Search Behavior We investigate the impact of price dispersion on consumer search behavior, while credibly controlling for market structure. Using the retail gasoline market on isolated, oligopolistic markets, as defined by small Greek islands, we exploit an excise duty tax increase policy as a plausibly exogenous shock to price dispersion. We directly measure consumer search using the number of user visits to a price information platform and mobile application. We find that the tax shock increases price dispersion and that in turn causes a short term increase in consumer search. The effect of price dispersion on consumer search remains regardless of market competition level. Asymmetric Pass-Through and Competition We study the pass-through to retail prices of four major changes in taxes for petroleum products (three increases and one subsequent decrease). We use daily pricing data from gas stations on small Greek islands, which define isolated markets with different number of competitors. First, we find that, on average, the pass-through of the tax hikes is five times higher than for the tax decrease. Second, the pass-through of the tax hikes increases with the number of competitors, but that of the tax decrease does not vary with competition (asymmetric competition effect). Third, there is significant asymmetry in the speed of price adjustments. Fourth, the asymmetric adjustment of retail gasoline prices cannot be explained by tacit collusion and the evidence points to search as the most plausible explanation.

This thesis examines a group of freemen trading in coal at Newcastle upon Tyne in the sixteenth century known as the Hostmen’s Company. The Newcastle hostmen had established an unincorporated guild by 1508 and held the monopoly in the sale of coal from the town’s port during the rapid expansion of the Tyneside coal trade in the half-century from 1550. Their guild was granted legal status by the Crown in 1600. Existing research on the activities of the Newcastle hostmen in the sixteenth century offers important evidence about their monopoly but leaves open questions about the organization and membership of their guild. No comprehensive history of the Tudor hostmen has been attempted before. There has been no detailed assessment of their ascendancy or the trade of their principal members during a period of decisive change in the mining and sale of Tyneside coal and England’s transition to an industrial economy. This thesis uses little-explored town chamberlains’ accounts to investigate the origins, trading networks, family connections, and business activities of the Tudor hostmen for the first time. The accounts show that hosting coal at Newcastle was confined to a small group of citizens drawn mainly from the town’s mercantile and civic elite, and their widows. Some strangers, gentlemen, craftsmen, and yeomen also participated in the hosting trade. After the Dissolution of the Monasteries and the armed rebellions of the English Roman Catholic nobles the principal hostmen used their capital, political power, and religious connections to acquire the bulk of newly available mining land in the vicinity of Newcastle, creating a de facto monopoly in the production as well as the sale of coal. The hostmen shipped Tyneside coal to markets on the English coast, France, the Netherlands, and the Baltic Sea and had gained control over Newcastle’s governance by the mid-sixteenth century. This thesis shows the importance of two urban-industrial coal dynasties founded by the Newcastle corn merchants James Lawson (d. 1544) and Henry Anderson (d. 1559). Members of the Lawson-Anderson oligarchy dominated mining and hosting in Elizabethan Newcastle at a time when there was a more than three-fold increase in the volume of coal leaving the town’s port by the seaborne trade. They mined extensively in the vicinity of Newcastle on the banks of the River Tyne, created the most developed industrialized landscape in Elizabethan England, and built the two biggest integrated coal businesses in the town while continuing to trade as merchants in a wide variety of commodities. This thesis shows that the Lawson-Anderson oligarchy continued to dominate the Tyneside coal trade in the first half of the seventeenth century, though some of their members suffered heavy losses in the Civil War.

Self-organizing nanopatterns can enable economically competitive, industrially applicable light-harvesting platforms for thin-film solar cells. In this work, we present transparent solar cell substrates having quasiperiodic uniaxial nanowrinkle patterns with high optical haze values. The self-organized nanowrinkle template is created by controlled heat-shrinking of metal-deposited pre-stretched polystyrene sheets. A scalable UV nanoimprinting method is used to transfer the nanopatterns to glass substrates on which single-junction hydrogenated amorphous silicon p-i-n solar cells are subsequently fabricated. The structural and optical analyses of the solar cell show that the nanowrinkle pattern is replicated throughout the solar cell structure leading to enhanced absorption of light. The efficient broadband light-trapping in the nanowrinkle solar cells results in very high 18.2 mA/cm2 short-circuit current density and 9.5% energy-conversion efficiency, which respectively are 35.8% and 39.7% higher than the values obtained in flat-substrate solar cells. The cost- and time-efficient technique introduces a promising new approach to customizable light-management strategies in thin-film solar cells.

Formate production via both CO2 reduction and cellulose oxidation in a solar-driven process is achieved by a semiartificial biohybrid photocatalyst consisting of immobilized formate dehydrogenase on titanium dioxide (TiO2|FDH) producing up to 1.16±0.04 mmolformate gTiO2-1 in 24 hours. Isotopic labelling experiments with 13C-labelled substrates support the mechanism of stoichiometric formate formation through both redox half-reactions. TiO2|FDH was further immobilized on hollow glass microspheres to perform more practical floating photoreforming allowing vertical solar light illumination with optimal light exposure of the photocatalyst to real sunlight. Enzymatic cellulose depolymerization coupled to the floating photoreforming catalyst generates 0.36±0.04 mmolformate mirr-2 after 24 h. This work thus presents simultaneous solar-driven valorization of waste streams, demonstrates the advantages of biohybrid photocatalysts in photoreforming for the first time and will provide inspiration for the development of future semi-artificial waste-to-chemical conversion strategies.

This thesis grapples with two distinct but interrelated issues: Indigenous climate sovereignty and the imagination of climate apocalypse. It is particularly concerned with how these two themes intersect in the High North, a landscape continually constructed as a periphery and frontier. In the pages that follow, I explore the misalignments between colonial projections of the land and its people, and the lived experiences of climate change and colonialism as I encountered them in two Alaska Native villages. This thesis is rooted in a multisited ethnography in Norton Sound, in Western Alaska. The ethnographic object of this study is not Alaska Native communities, but rather the forms of politics that connect rural Indigenous governments to colonial centres of power in the United States Federal government. In that sense, the research presented here is as much a political ethnography as it is an environmental one. The conclusions presented in this thesis are fourfold. 1) Marginalised Alaska Native communities face a neo-colonial pressure whereby, in order to receive assistance, they are required to adopt the bureaucratic forms and logic of their colonisers; 2) the manner in which the Arctic has been enlisted to support popular apocalyptic climate discourse echoes the modernist role the region played in 19th- and 20th-century constructions, as a mirror for urban humanity; 3) social scientists and humanities scholars have broadly neglected the importance of situating knowledge about climate change and ecological futures, and instead resort to sweeping, planetary gestures; and 4) urban narratives of climate apocalypse offer a potent antidote to political alienation.

Removal of nitrogen compounds in wastewater represents more than 10% of the total electrical demand of the integral water cycle. However, more than 80% of the nitrogen in wastewater comes from urine, where it is highly concentrated in the form of urea (20000 mg L-1). Urea contains a significant amount of hydrogen in its structure which, if recovered, makes urea a potential source of green energy. This thesis demonstrates a novel approach for the energy recovery from urea present in urine at the production source, using decentralised wastewater treatment systems. A new process has been developed in this thesis based on the integration of three steps. In the first step, adsorption is used to recover urea from urea, overcoming the energy limitations of thermal treatments applied to big water volumes. In the second step, thermal treatment is used to desorb the urea, achieving the regeneration of the adsorbent and the production of ammonia. Finally, in the third step, ammonia is used as hydrogen storage molecule to catalytically produce hydrogen on demand. The adsorption of urea is evaluated using activated carbon, determining that urea adsorbs due to physical interactions with i) delocalised π electrons of the pristine surface of the carbon and ii) carboxyl functional groups. The adsorption of urea is reduced when working with real urine due to the presence of organic compounds with affinity for activated carbon that interferes with the adsorption of urea. Thermal treatment of adsorbed urea leads to desorption of urea and regeneration of activated carbon showing a stable urea adsorption capacity during 4 consecutive adsorption/desorption cycles. Simultaneously, ammonia is produced with a 50 – 60 % yield, which is coupled with an ammonia decomposition catalyst to obtain hydrogen. Pilot trials are developed and installed in relevant environments as conventional and waterless urinals, where a social analysis shows a good acceptance towards the solution and pointed some aspects for improving. Energy analysis shows a positive balance due to the combination of the hydrogen produced and the savings in the traditional nitrogen removal. Furthermore, economic analysis indicates that the direct use of ammonia to produce electricity or fertilisers can be a competitive alternative to the obtention of hydrogen.

Der Klimawandel wird sich voraussichtlich auf das Grundwasser auswirken, aber die Prognosen sind sehr unsicher. Die Quantifizierung der historischen Auswirkungen ermöglicht ein besseres Verständnis der Reaktion des Grundwassers, wurde aber aufgrund des komplexen Einflusses verschiedener Faktoren, wie Grundwasserentnahme für die landwirtschaftliche Bewässerung und Landnutzungsänderungen, nur selten untersucht. Diese Arbeit zielt darauf ab, zum Verständnis und zur Quantifizierung der historischen Auswirkungen von Klimawandel und -schwankungen auf das Grundwasser durch drei miteinander verbundene Forschungsfragen beizutragen: Frage 1: Wie sensitiv reagieren der Grundwasserstand und die Grundwasserneubildung auf Klimaschwankungen in Australien? Frage 2: Wie stark sind die Veränderungen des Grundwasserstands auf den anthropogenen Klimawandel in Australien zurückzuführen und wann haben sich diese Auswirkungen auf das Grundwasser bemerkbar gemacht? Frage 3: Wie haben und werden sich die langfristigen Klimawandel und -schwankungen auf den Grundwasserabfluss (niedriger, mittlerer und hoher Abfluss) in einem großen Karsteinzugsgebiet (schneebeeinflusst, gemäßigtes Klima) in Mitteleuropa auswirken? Die Frage 1 wurde durch Quantifizierung der Sensitivität des Grundwasserstands und der Grundwasserneubildung gegenüber Klimaschwankungen in Australien untersucht. Insgesamt 4350 Messstellen wurden zunächst mit der Zeitreihen-Grundwasser-Toolbox HydroSight modelliert, und 1143 (26%) davon wurden als klimadominierte Messstellen identifiziert. Zur Quantifizierung der Grundwassersensitivität wurde dann ein multipler linearer Regressionsansatz angewandt, der an Studien zur Elastizität von Wasserflüssen adaptiert wurde. Die Ergebnisse zeigen, dass der Grundwasserstand und die Grundwasserneubildung etwa achtmal sensitiver auf Niederschläge reagieren als auf Veränderungen der potenziellen Evapotranspiration. Die inhärenten Eigenschaften der Gebiete, wie Klimatyp und Hydrogeologie, scheinen eine wichtige Rolle bei der Kontrolle der Grundwassersensitivität zu spielen. Die Frage 2 wurde untersucht, indem historische Veränderungen des Grundwasserstands in Australien festgestellt und auf den anthropogenen Klimawandel zurückgeführt wurden. An den vom Klima dominierten Standorten wurde ein Modellierungsexperiment durchgeführt, um die Veränderungen des Grundwasserstands sowohl in der faktischen als auch in der kontrafaktischen (natürlichen) Welt mit und ohne menschlichen Einfluss zu simulieren. Die Ergebnisse zeigen, dass 90% der Standorte seit den 1950er Jahren eine signifikante Grundwasserabsenkung erfahren haben, die auf den anthropogenen Klimawandel zurückzuführen ist. Im Südwesten Australien ist die Abnahme am höchsten und liegt viermal so hoch wie der nationale Median (-74 gegenüber -19 mm pro Jahr). Diese Ergebnisse gehören zu den ersten, die zeigen, dass das Grundwasser bereits seit längerer Zeit den negativen Auswirkungen des anthropogenen Klimawandels leidet. Zur Beantwortung von Frage 3 wurde die Reaktion des Grundwasserabflusses auf Klimawandel und -schwankungen in einem schneebeeinflussten Karsteinzugsgebiet der gemäßigten Breiten (Blautopf) in Süddeutschland zwischen 1952 und 2100 quantifiziert. In dieser Studie wurden statistische Methoden und konzeptionelle Modellierungen eingesetzt, um die langfristigen Auswirkungen zu quantifizieren. Die Ergebnisse zeigen, dass die Veränderungen des jährlichen mittleren und niedrigen Abflusses nicht signifikant waren, aber der jährliche Spitzenabfluss hat sich aufgrund der weniger intensiven Schneeschmelze auf einen niedrigen Wert (< 13,6 m3/s) verschoben. Trotz nicht signifikanter historischer Veränderungen werden alle hoch-, niedrig- und mittleren Abflüsse bis zum Jahr 2100 voraussichtlich abnehmen. Diese Ergebnisse können auf potenzielle Risiken der Wassermangelversorgung an ähnlichen klimatischen und geologischen Standorten hinweisen. Die Quantifizierung der historischen Auswirkungen von Klimawandel und -schwankungen auf das Grundwasser trägt zu einem besseren Verständnis der Reaktion des Grundwassers bei und erhöht die Zuverlässigkeit der Vorhersagen. Nur wenn wir die Vergangenheit verstehen, können wir bessere Vorhersagen für die Zukunft machen.