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UNIO MYSTICA AND THE AURORA CONSURGENS: MYSTICAL THEOLOGY IN A LATE MEDEIVAL ALCHEMICAL TREATISE
Get PDFThis thesis examines a late medieval alchemical treatise known as the Aurora Consurgens, which is ascribed to the early decades of the fifteenth century. The Aurora was among the first of its kind in a tradition of poetico-rhetorical alchemy that became popular in the late middle ages and early modern period. While it is indisputable that early Latin alchemical texts contained allegorical language and religious symbolism, the Aurora heralded a new form of alchemical literature, where mysticism became thoroughly and inseparably interpolated with the operations of the laboratory. The Aurora is framed as a dialogue between an unnamed alchemist and Sapientia, a female embodiment of God’s wisdom, which in the text, is conflated with the philosopher’s stone. This thesis focuses on a series of visions that appear throughout the document. These visions invoke the unitive imagery of late medieval mystical theology and contain many of the themes that appear in medieval contemplative literature. These are, namely, the image of the ‘cloud’ that appears in the tradition of pseudo-Dionysian mystical theology, motifs of darkness and illumination, purgation, and union with the divine. The principal argument contends that the author of the Aurora Consurgens used the motifs of mystical theology to elucidate his understanding of the alchemical work
Unsupervised Automatic Detection Of Transient Phenomena In InSAR Time-Series using Machine Learning
Get PDFThe detection and measurement of transient episodes of crustal deformation from global InSAR datasets are crucial for a wide range of solid earth and natural hazard applications. But the large volumes of unlabelled data captured by satellites preclude manual systematic analysis, and the small signal-to-noise ratio makes the task difficult. In this thesis, I present a state-of-the-art, unsupervised and event-agnostic deep-learning based approach for the automatic identification of transient deformation events in noisy time-series of unwrapped InSAR images. I adopt an anomaly detection framework that learns the ‘normal’ spatio-temporal pattern of noise in the data, and which therefore identifies any transient deformation phenomena that deviate from this pattern as ‘anomalies’. The deep-learning model is built around a bespoke autoencoder that includes convolutional and LSTM layers, as well as a neural network which acts as a bridge between the encoder and decoder. I train our model on real InSAR data from northern Turkey and find it has an overall accuracy and true positive rate of around 85% when trying to detect synthetic deformation signals of length-scale > 350 m and magnitude > 4 cm. Furthermore, I also show the method can detect (1) a real Mw 5.7 earthquake in InSAR data from an entirely different region- SW Turkey, (2) a volcanic deformation in Domuyo, Argentina, (3) a synthetic slow-slip event and (4) an interseismic deformation around NAF in a descending frame in northern Turkey. Overall I show that my method is suitable for automated analysis of large, global InSAR datasets, and for robust detection and separation of deformation signals from nuisance signals in InSAR data
New Synthetic Routes for Natural and Synthetic Fragrance Ingredients
Get PDFResearch & development of alternative routes for fragrance ingredients currently produced by International Flavours & Fragrances Inc. (IFF) in Benicarlò, Spain is reported herein. Past and current industrial syntheses of these ingredients are initially summarised as well as their primary role in the industry. The research disclosed has focused on designing and developing sustainable and safe methods for their industrial preparation and, where possible, evaluation to/of continuous flow approaches.
The first target was the musky, earthy natural ingredient known as Veramoss. For this molecule, three alternative synthetic pathways were explored starting with cheap and widely available raw materials such as butanone, dimethyl malonate, methyl acetoacetate, methyl crotonate, and acetaldehyde. Despite being unable to achieve the final compound, the study enabled the development of a continuous-flow Knoevenagel reaction employing polymer-supported dimethylamine catalyst to obtain dimethyl ethylidene malonate in moderate yields (38%) as well as an interesting one-pot methodology for the preparation of 4-chlorohex-4-en-3-one from dimethyl oxalate and butanone in good yields (76%). These developed methodologies could become interesting starting points for future works. Along with route scouting, the main goal of the project was to propose an improved “green” alternative to the currently employed toxic elemental chlorine. To this aim, four main alternative chlorination processes were investigated, one of which proved to be the candidate of choice: trichloroisocyanuric acid (TCCA). An optimisation based on utilizing TCCA was carried out by employing one-factor-at-the-time (OFAT) and design of experiment (DoE) approaches. The optimised one-pot procedure was scaled up to multi-grams quantities allowing the isolation of Veramoss whose quality was validated for commercial purposes. Furthermore, the study also proposed a de novo procedure for the purification of discoloured Veramoss obtained from mischarge and side reactions during chlorination. The methodology based upon selective phenol-amine H-bonded complex formation allowed the recovery of purified white material in 60% overall yield, reducing waste and the need to dispose of discoloured batches.
The second target molecule was the newly established IFF compound Ambertonic™, a synthetic tricyclic musk odorant featuring a pyrimidine scaffold. The investigation focused on finding valuable alternative routes starting from a readily available intermediate: Cashmeran. Five viable methods were explored, however, only one allowed the ultimate cyclisation to occur. The effective strategy was then optimised for the preparation of the material. Hence, a two steps one-pot synthesis was developed to yield Ambertonic™ in good yield (53%). The methodology consists in the formylation of the dihydro-cashmeran material with subsequent pyrimidine formation inspire by a publication by Bredereck et al. The optimisation of both stages were initially found to be challenging presenting low yields, solid precipitation, and formation of impurities. Scouting different reaction conditions and parameters, the issues were tackled and eventually solved. Additionally, the first SCXRD structure and racemic resolution of the trans-isomer was carried out allowing us to gain a deeper understanding of the absolute configuration of the active odorant species.
The final target investigated was dehydroherbac, a key intermediate for the preparation of the fresh, green odorant known as Galbascone. Three synthetic routes were envisioned starting from different raw materials such as acrylonitrile, 4,4-dimethylcyclohexanone, 5-methyl-hexan-2-one, and 3-carene. Two of the proposed strategies aimed at preparing an enaminone intermediate which undergoes de-amination through selective enamine reduction and elimination. The latter procedure ultimately proved to be impracticable on the desired scaffold. Regardless of the outcomes, a continuous-flow photo-catalysed method for the preparation of a cyano-ketone was optimised to yield 630 mg h-1 of material in 63% isolated yield as a proof-of-concept study. Employing 3-carene as a precursor was also considered through catalytic hydrogenolysis and CH activation of a tertiary carbon. Such a strategy allowed access to three possible oxidative hydroxylation methods as described in the literature utilising dioxiranes, and peracids. Due to the lack of time, the investigation was not completed, however it has established a solid foundation for future work. The project also involved the optimisation of a previously designed route to Galbascone via a Henry-Nef reaction. Kinetic studies performed on the amine-catalysed Henry reaction enabled establishment of a better understanding of the latter and reduced the amount of nitroethane employed for the reaction.
In summary, potential preparative routes to the three fragrance ingredients were developed and optimised. The process utilised known chemistry which employs safe and cheap raw materials. Both the developed methodologies for Veramoss and Galbascone have also been considered for scale up at IFF in Benicarlò, achieving interesting manufacturing results
Understanding the gamma-ray emission from Globular Clusters
Get PDFObservations with the Large Area Telescope (LAT) on-board the Fermi Gamma-ray
Space Telescope have led to the discovery of gamma-ray emission from many Globular
Clusters. The high stellar encounter rates in Globular Clusters favour the formation
of millisecond pulsars, which have been postulated as the source of the gamma-ray
emission. However, the evidence for this is indirect and there have been limited studies
attempting detailed spectral comparison between Globular Clusters and their millisecond
pulsar populations. The detection of pulsed gamma-ray emission would constitute direct
evidence of millisecond pulsars contributing to the Globular Cluster emission.
In this work, I use 13 years of Fermi-LAT data to perform a detailed spectral analysis of 6 Globular Clusters where no pulsed gamma-ray emission has been reported, but
millisecond pulsars have been detected using radio telescopes. I also analyse the Globular Cluster NGC 6624, where pulsed gamma-ray emission has already been observed
and find that a single millisecond pulsar can account for the majority of NGC 6624’s
gamma-ray emission over 13 years. I then find no evidence of any statistically significant pulsed emission in any of the Globular Clusters I selected. Based on these findings
and motivated by previous studies, I consider the possibility of dark matter annihilation contributing to the Globular Cluster emission. I perform likelihood fits of three
scenarios for the Globular Cluster emission: dark matter only, millisecond pulsars only,
and a combination of millisecond pulsars and dark matter. I use these results to place
upper limits on the millisecond pulsar contribution to the gamma-ray emission in each
Globular Cluster. I find evidence that the millisecond pulsars in some of the Globular
Clusters are fainter than those in the Galactic neighbourhood. Finally, I conclude that a
dark matter component cannot be ruled out for any of the Globular Clusters I studied
Determining the geothermal potential of natural gas fields in the Southern North Sea
Get PDFRenewable energy uptake must increase to reduce carbon emissions and curb today’s unprecedented rate of global warming. CO2-based geothermal energy extraction could be used to produce near zero-carbon power from the heat stored in depleted natural gas reservoirs. CO2-plume geothermal (CPG) is a conceptual technology designed to produce power by circulating CO2 through permeable and porous formations sealed by low- permeability cap rocks, ultimately storing industrial quantities of CO2 in the subsurface. Few feasibility studies have considered the application of this technology to wide-scale geographical areas and no offshore CPG prospects have been evaluated. Several factors make natural gas fields in the Southern North Sea (SNS) promising CPG prospects; geothermal gradients are higher on average than those found onshore in the UK, infrastructure is already in place, extensive geological data are available, and seawater can be used as a heat sink to improve CPG performance. In this research, CPG power production is estimated for 64 SNS gas fields using a few identified and simplifying assumptions.
The South Sean field was selected as the field best suited for CPG in terms of power production potential and practicality. Power production was re-estimated for South Sean with increased accuracy. The gas fields are classified as geothermal resources following the United Nations Framework Classification for Resources (UNFC). Findings indicate that moderate amounts of power (in the order of kilowatts electric) could be produced from 50 of the 64 fields. An injection-production well doublet configured to South Sean could produce from 59 kWe to 552 kWe depending on well diameter sizing. This research demonstrates that low parasitic cooling loads can be achieved using seawater as a cooling medium, giving offshore CPG systems an edge over their onshore counterparts. All fields are classified under the UNFC system as having additional quantities in place, highlighting the need for a follow- up economic analysis
Decoding the intention to expatriate: A comparative analysis of employees from developed and emerging countries
Get PDFAssigned expatriates (AEs) are strategic resources for the successful operation of
multinational companies (MNCs). More recently, though, employees have been more
reluctant to expatriate. In this context, it is crucial to investigate the predictors of employees’
intention to expatriate to widen organisations’ talent pool. Notably, while most expatriation
research has focused on individuals from Western developed countries, very limited research
has been conducted on those from Latin emerging countries. In this respect, this study aimed
to identify the psychological process involved in forming developed and emerging
employees’ intention to expatriate. The first step was to develop a conceptual framework,
which integrated the self-determination theory (SDT) and the theory of planned behaviour
(TPB). It assumes that autonomous and controlled motivations from SDT affect employees’
intention to expatriate through the socio-cognitive variables (attitude, subjective norms - SN,
and perceived behavioural control - PBC) from TPB. In addition, the model incorporated
individual-subjective and national-level moderating variables, psychic distance (PD) and
cultural distance (CD). A sample of 431 AEs, of which 218 were from emerging countries
(Brazil and Mexico) and 213 were from developed countries (Germany, the Netherlands, the
United Kingdom, and the United States), answered an online questionnaire. Descriptive
statistics showed that, although the samples of developed and emerging AEs resemble in
aspects such as the proportion of male expatriates and family composition, they differ in
many other aspects: emerging AEs are fluent in more foreign languages than developed AEs,
and have, on average, three years less of previous international experience than developed
AEs. The model was tested using multi-group structural equation modelling, and the results
support a different psychological process explaining developed and emerging AEs’
expatriation intention. For example, autonomous motivation and PBC are the key predictors
of developed AEs’ intention to expatriate; conversely, controlled motivation and attitudes are
the leading antecedents of emerging AEs’ intention to expatriate. These results can be
primarily linked to employees’ cultural and socio-economic backgrounds. Moreover, the
types of motivation directly affected employees’ intention to expatriate, indicating that the
expatriation decision is very complex and the result of a combination of influences that can
be cognitive and driven by motivations. The results also support the moderating role played
by the CD and PD, which alter the motivational and cognitive processes explaining
employees’ expatriation intention. The findings of this study shed new light on the
international human resource management and expatriation literature. Foremost, this research
provides a more comprehensive appreciation of the antecedents of employees’ expatriation
intention, adding another layer of understanding to previous studies, and emphasises the
lasting impact of the country of nationality on employees’ formation of their intention to
expatriate
The issues of poverty and participation in community development: A case study in Terengganu, Malaysia
Get PDFIn Malaysia, community development has been used primarily by the government as an approach to develop and empower the community, especially the economically disadvantaged population, with the main aim of addressing poverty within this group. Many community development programmes designed to address poverty have been provided for this group, but the government data shows that the relative poverty rate is still persistent (with a slight increase in recent years) despite all the programmes provided. This study explores how community development has been used as a response to address poverty in this context and the related issues of social inequalities in relation to improvement in the participants’ quality of life.
This study adopted a qualitative design in a rural and an urban area in Terengganu, Malaysia and focused on a range of different community development interventions responding to poverty amongst the Bumiputera population. A total of 34 semi-structured interviews were conducted and the collected data were then systematically coded and thematically analysed. The research found that participation in community development activities affect the experiences of particular people living in poverty in a way that they remain in relative poverty despite their participation in those activities (alongside other individual approaches). The persistence in relative poverty could be maintained by the social dynamics issues embedded within implemented programmes whilst social aspects are also important and need to be taken into account in designing the community development programmes for the people. Nevertheless, it was found that through participating, the participants had improved their quality of life to some extent, especially in terms of social and emotional aspects. A model of community development that prioritises the voice of the participants (bottom-up approach) is recommended while at the same time, shifting the focus of the interventions from a deficit-based to an asset-based approach could potentially help to address the persisting relative poverty among the participants
Methodism and the British Armed Forces from John Wesley to the Second World War
Get PDFThe relationship between British Methodism and Britain’s armed forces has been under-researched. Whereas the past two decades have seen an extensive reappraisal of the connections between religion and the military, most of this work has focused on the Anglican and Roman Catholic traditions. However, the comparative neglect of Methodism is both noteworthy and paradoxical, especially given the importance of the soldier and sailor in the development of Methodism in the British Isles and worldwide. This thesis argues that the links between the movement and the British armed forces were significant throughout Methodism's first two hundred years. Despite some ambiguity in attitudes towards soldiers and sailors, Methodists maintained an active interest in the spiritual health and temporal welfare of the British soldiers, sailors and airmen. That commitment to the armed forces was constant throughout the movement’s history, underpinned by a political loyalism that was central to Methodism, particularly Wesleyan Methodism. The relationship is analysed by exploring the presence of Methodists in Britain’s forces, by studying the links that developed between the armed forces and the movement, and by investigating the development of chaplaincy and other kinds of ministerial and lay outreach. The struggle for recognition and representation in the army, navy and air force will be shown to mirror Methodist striving for political and societal acceptance. Opposition to engagement with the armed forces will be explored, and a prevailing narrative challenged: that Methodist attitudes towards peace and war, especially in the twentieth century, were predominately pacifist
Black Holes with Topological Defects: The C-metric in Three and Four Dimensions
Get PDFWe examine the effects of accelerating both isolated and coupled black
holes in a variety of contexts.
A detailed investigation of the thermodynamic phase space of a charged, rotating,
and accelerating black hole placed in a background of negative cosmological constant
is performed, and novel effects due to acceleration are identified. A modified
Christodoulou-Ruffini formula for the solution is shown to hold, providing compelling
evidence that the mass used, identified using holographic techniques, is the correct
one.
Motivated by the holographic results, we then identify the mass of an array of black
holes connected by conical deficits and without cosmological constant, of which the
C-metric is a special case. This mass is shown to obey a first law of thermodynamics,
with the string tensions acting as a thermodynamic charge. The black holes are
coupled in such a way that a variation applied to one affects all of the others. A
similar Christodoulou-Ruffini formula is shown to hold in this context.
We then examine a family of three-dimensional solutions analogous to the four-dimensional C-metric.
We identify three classes of geometry. From these, we construct stationary,
accelerating conical deficits; novel one-parameter extensions of
the static BTZ family which resemble the C-metric; and braneworld solutions. We
comment on the extent to which our solutions may be considered "accelerating black
holes"
Towards the trapping of single potassium atoms in optical tweezers
Get PDFThis thesis presents the development of a toolbox for trapping 39K atoms in a magneto-optical trap with the future vision of trapping a single atom in an optical tweezer. Such technique promise with potential applications in the fields of quantum computation, quantum information, quantum simulation, and precision measurement. In this work, we studied spectroscopic of two different transitions of 39K then we trap 39K in an MOT, which is a small step toward optically trap a single 39K atom in a tweezer.
In the second chapter, we present a summary of the theoretical framework relating to laser cooling and trapping. Also, include a detailed description of the energy level structure and challenges for cooling potassium. In the third chapter, we demonstrated a laser frequency stabilization technique. We include theoretical understanding along with the experimental results. We compare the D1 and D2 transitions of 4S to 4P lines of 39K by various experimental parameters.
In the fourth chapter, we present a history of pre-cooling of alkali atoms is necessary. We also explain our experimental apparatus require required for laser cooling. Then we discuss the laser system used for the experiments along with the alignment technique for the laser beam and AOMs alignment to control the frequencies. We also characterized and set up the tapered amplifer to increase the laser beam power.
And in chapter ve, we present the optimization and characterization of the different experimental parameters of the pyramid MOT to produce as much as bright MOT as possible.
In chapter sixth, we present details of the theoretical framework required to understand the absolute absorption of 4S to 5P transition of 39K along with the experimental results. For the future extension, to study the precision measurements to identify the Rydberg states of cold 39K atoms. And in order to cool down 39K atoms beyond the Doppler cooling limit, one can use degenerate Raman sideband cooling via the 4S1/2 to 5P1/2 transition.
Finally, in the last chapter, we discuss the immediate future experiment in order to achieve a single atom in an optical tweezer. Therefore, after slowing down the atoms in the pyramid chamber as we did for 39K, one can trap 39K atoms in a 3D-MOT in the science chamber, then using optical tweezers with a specific wavelength, one can trap 39K single atom in optical tweezers
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