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Where’s the benefit? Exploring outcomes relating to enterprise, poverty and the UK welfare system
Get PDFThe primary aim of this research is to contribute towards the advancement of knowledge
on self-employment as a context of low income. In particular, this research explores
experience of claiming welfare benefits amongst self-employed people in the UK.
Historically the UK has encouraged self-employment in the belief that the greater the
business start-up rate, the better it is financially for the economy. This belief has persisted
throughout the years despite research to the contrary. The rates of self-employment have
grown considerably with a lot of the growth attributed to the gig economy and bogus self-employment.
Throughout recent decades academic research has tended to focus on how entrepreneurs
can be created and improved, as well as how their business and economic contributions
can be increased. This has tended to fuel the neo-liberal narrative that the value of
entrepreneurship is mostly financial, for individuals and for society as a whole. However,
recently attention has started to turn towards the value of self-employment to the
individual in non-pecuniary forms such as skills development, confidence and self esteem, flexibility and work life balance and enjoyable forms of work. The thesis explores
value and it explores it in the context of the capitals available to individuals who are self employed and experiencing poverty.
An inductive, qualitative approach was used for this study. In-depth, semi-structured
interviews were carried out with 40 individuals who were self-employed, in poverty and
either claiming welfare benefits or entitled to claim. The data collected was analysed
thematically using a mix of computer software and manual processes.
Key findings from this study include that the personal circumstances of the individual
influence decisions. These circumstances relate to domestic life including caring
responsibilities or health problems, and to other capitals such as education. Furthermore,
the findings highlight the role of the welfare system and how financial support influences
personal and business outcomes. In some cases, the restrictions and complexities of the
UK welfare system meant the individuals deliberately kept their businesses small despite desires to grow because the insecurity of poverty meant they could not risk going without
their benefit payments.
From a theoretical perspective, the research draws from capitals theories and
entrepreneurial capital theory in particular. The key theoretical contribution is a
reconceptualised model of entrepreneurial capital, placing the individual at the centre
with capital resources embedded within personal circumstances. From a policy
perspective, the thesis contributes towards policy debates on how the UK welfare system
supports those who are self-employed and experiencing poverty
Nanomaterial fate and bioavailability in freshwater environments
Get PDFGiven the widespread use of silver nanomaterials (AgNM), their accidental or intentional
release into the environment is inevitable. AgNM release into riverine systems is a daily
occurrence, and following their release, they will undoubtedly interact with naturally
occurring organic and inorganic particulates and sediment interfaces. At this point, AgNM's
long-term threat to freshwater ecosystems is unclear. We must develop our understanding
of AgNM fate, toxicity, and bioavailability using testing approaches that systematically
investigate AgNM environmental interaction within single-factor and multifactor systems.
This body of research aimed to comprehensively examine selected AgNM particles that
were tracked within parallel fate scenarios and toxicity and bioavailability studies. Results
showed contrasting behavior between the two tested AgNM. Findings also demonstrated
that low shear flow is a significant factor influencing the flocculation and settling rates of
AgNM, which differentially regulated the persistence and residence time of aqueous phase
AgNM within simulated riverine systems. Experiments with low shear flow showed a
significant increase in AgNM water column removal and modulated the physicochemistry
differentially compared to quiescent systems. The findings on the influence of bed
sediment interactions with waterborne AgNM demonstrated that they are a vital process
that increases the transfer and exchange of AgNM from the water column to the bed.
Toxicity studies showed how abiotic factors could modulate toxicity differentially between
aquatic species and how inorganic and organic matter can increase and decrease AgNM
toxicity. Exposure studies contrasting singular and multifactor exposures with and without
low shear flow demonstrated that they modulate the exposure of AgNM significantly
differently. In conclusion, the proof-of-concept flume designs for testing the environmental
fate and exposure of AgNM showed promise and that, with further refinement, could be
further incorporated into the life-cycle testing framework of ENMs, to produce accurate
semi-empirical coefficients for environmental models for the assessment of hazard
Recycling of waste polymers through catalytic depolymerization
No full textAbstract unavailable. Please refer to PDF. Restricted access until 31.08.2031
What does this notation mean anyway? Interpreting BNF-style notation as it is used in practice
Get PDFBNF (Backus Naur Form) notation, as introduced in the Algol 60 report, was followed
by numerous notational variants (EBNF ISO (1996), ABNF Crocker et al. (2008), etc.),
and later by a new metalanguage which is used for discussing structured objects in Computer Science and Mathematical Logic. We call this latter offspring of BNF MBNF
(Math BNF). MBNF is sometimes called “abstract syntax”. MBNF can express structured objects that cannot be serialised as finite strings. What MBNF and other BNF
variants share is the use of production rules, whose form is given below, which state
that “every instance of ◦i
for i ∈ {1, . . . , n} is also an instance of •”.
• ::= ◦1 | · · · | ◦n
This thesis studies BNF and its variant forms and contrasts them with MBNF production rules. We show via a series of detailed examples and lemmas that MBNF, differs
substantially from BNF and its variants in how it is written, the operations it allows,
and the sets of entities it defines. We demonstrate with an example and a proof that
MBNF has features that, when combined, could make MBNF rule sets inconsistent.
Readers do not have a document which tells them how to read MBNF and have to learn
MBNF through a process of cultural initiation. We propose a framework, MathSyn,
that handles most uses of MBNF one might encounter in the wild
Numerical simulation of surfactant flooding across scales in carbonate reservoirs
Get PDFConventional carbonate reservoirs contain most of the world’s oil and gas reserves.
However, their recovery factors after primary and secondary oil recovery remain low
overall because of the multiscale geological heterogeneities and the fact that carbonates
are usually mixed- to oil-wet. Surfactant injection has the ability to increase oil production
from carbonate reservoirs by changing the wettability of the rock and reducing the
interfacial tension.
In this thesis, I combine the analysis of laboratory experiments with simulation studies to
understand and quantify the impact of geological heterogeneity on the effectiveness of
surfactant-based enhanced oil recovery at the core, inter-well, and sector scales. I
parameterised surfactant models using data from two surfactant laboratory experiments,
one where capillary forces dominated (spontaneous imbibition) and one where viscous
forces dominated (core-flood). The parameterised surfactant models were then deployed
to high-resolution inter-well and sector-scale models that captured small-scale geological
heterogeneities observed in two outcrop analogues from France and Morocco.
Our simulation results showed a broad range of recovery predictions. The variability of
the recovery behaviour arises from the choice of surfactant model parameterisation (i.e.,
spontaneous imbibition vs. core-flood) and the way the heterogeneity in the inter-well
and sector models was upscaled, i.e., simplification of the reservoir model
Bodily perception of our hands, feet, and whole body
Get PDFThis thesis examines differences in sensing, imagining and feelings towards our hands,
feet, and whole body in healthy participants, via three online experimental studies. The
first chapter describes the theoretical background used to develop this thesis,
encompassing the most up-to-date theories on body representation that form the basis of
our knowledge on the topic.
The second chapter (sensing) describes a study exploring whether spontaneous sensations
(SPS), in other words, sensations we feel without external stimulation, differ between our
hands, feet and whole body. This study also explores whether visual attention influences
the experience of SPS. One hundred and seventy-five individuals completed an SPS task
measuring the general tendency to experience SPS (SPSTrait) and the experience of SPS
in a precise moment (SPSState), along with an endogenous visual attention task. The results
show that the SPS experience differs between the precise moment and the general
tendency, and across our body districts. My findings show that we tend to experience
SPS, in general, more strongly in our whole body than our feet (SPSTrait), while our in-the-moment attention to SPS (SPSState) is the same across the body districts. This
experience does not depend on visual attention differences.
The study described in the third chapter (imagining) explores whether the representation
of the body in action, measured via motor imagery, differs between our hands, feet, and
whole body depending on the levels of awareness required by the task administered. Sixty
participants completed a series of Implicit Association Tests (a more implicit motor
imagery task), a Mental Motor Chronometry task (a more explicit motor imagery task),
and a visual imagery questionnaire. All tasks targeted the representation of hands, feet
and whole body. The results show that when the task requires less awareness to be solved,
in other words, it is more implicit, there are no differences between hands, feet and whole
body. While differences can be found when more awareness of our own body
representation and related processes is required, with a stronger motor imagery for the
hands than the whole body. This finding is not due to visual imagery differences, as
demonstrated by the results of the visual imagery questionnaire I administered.
The study described in the fourth chapter (feelings towards our body) adopts a similar
approach to the previous one, but this time I focused on emotional body representations,
measured via body image. I explored whether these representations differ in our hands,
feet, and whole body, considering more implicit and explicit levels of awareness. Sixty-seven participants completed a series of Implicit Association Tests (a more implicit body
image task) and a Body Image Satisfaction Visual Analogue Scale (a more explicit body
image task) for hands, feet and whole body. The results show no differences in the more
implicit level of awareness in hands, feet and whole body, while differences are apparent
at a more explicit level of awareness, with higher scores for body image satisfaction for
the hands than the whole body and marginally significant lower scores for feet than hands.
In the fifth and final chapter, a general discussion of the findings, their novelty and the
impact on applications of body representation is presented. Overall, my studies show that
the mental representations of our hands, feet and whole body are different. Hands appear
to have a more pronounced effect on our body representation at a more explicit level of
awareness and at imagining and feelings towards our body representational levels. This
suggests the possibility of a separate and different representation for hands, depending on
the level of awareness (more explicit) and representation (imagining/feelings towards our
body
The interdependent co-evolution of path dependency and dynamic capabilities
Get PDFResearch into dynamic capabilities (DC) has evolved from creating taxonomies of the
concept, to reconciliation of competing definitions, to the operationalization of the concept
to better determine the impacts of DC. Environmental conditions that underpin significant
change in companies requires investigation into the factors that create the conditions
necessary for such change. Although DC are not a necessary condition for organizational
change, they are possibly a prerequisite for change in innovation. As DC are path dependent
(PD), the PD state may have a bearing on the relevant DC. Paradoxically, DC may alter the
PD state. Although research has explored the relevance of path-dependent DC to innovation,
absent in the research is an understanding of the mechanics of how they co-evolve and what
specific DC micro-foundations are relevant across the path cycle. This study does so within
the context of the cycle of innovation across the path. Utilizing a single longitudinal case
approach on a specialty steel company, supported by the epistemology of critical realism and
a purposive sample of management, the study incorporated the critical incident method
through semi-structured interviews to identify the key activities and decisions supporting the
adoption and implementation of incremental and new innovations relevant to specialty steel.
Using a general inductive approach, the narrative from these interviews was analyzed to
aggregate the activities along key themes that represented stages of the path cycle and
identified DC micro-foundations and characteristics of PD. It was then determined how the
changes in DC and PD afforded evidence of the mechanics of co-evolution. The findings
from this study suggest that the pattern of co-evolution is characterised by oscillating states
of flexibility and rigidity of PD. DC present themselves in key “triggering events” that
emerge from higher order management initiatives and create inflexion point that shifts the
balance of flexibility and rigidity. The PD state remains relatively constant between these
triggering events, during which PD DC emerge and influence the continuous process of
innovation. Flexible elements of PD have bearing on the relevant DC, while the rigid
elements, in conjunction with internal and external context, mediate the innovation outcome
and type. This study presents a detailed interaction of elements that influence the co-evolution of PD and DC. Moreover, it reconciles the dichotomy between PD and DC by
suggesting DC, at certain phases, may influence PD, upon which these altered PD enable DC
throughout the innovation process
Exploring interpretations of urban vitality in newly developed residential areas. Cases in the peripheries of Madrid and Edinburgh
Get PDFThe concept of urban vitality celebrates the diversity and vibrancy of central parts of cities
and its principles are adopted as overarching sustainable planning and design guidance
worldwide. However, there is less evidence about how vitality operates in non-central
locations. This research adopts a phenomenological and interpretivist stance to explore
experiences of vitality through people’s daily practices in non-central residential areas. This
is deployed through a case study methodology which examines two ongoing residential
developments in the outskirts of Madrid and Edinburgh. The qualitative method of go-along including walking interviews with local residents and participant observation,
complemented with semi-structured interviews with local entrepreneurs and professional
stakeholders, provide a broad understanding of the ways in which vitality is experienced,
interpreted and implemented in Spain and Scotland.
This research reveals that vitality is a desirable quality of the environment even in non-central, not fully established locations undergoing change. Vitality is associated to
opportunities for sociability, active mobility, and participation at the local level. Everyday
spaces and opportunities near home provide contact between diverse people, encourage
healthy behaviours and help people feel connected to the local, thus contributing towards a
positive relationship with place. The vitality of non-central locations has got unique
characteristics, for it mediates between the vibrancy of cities and the quietness associated to
non-central living. Vitality is experienced through informal forms of interactions within
places that do not concentrate a busy activity, but offer attractive stimuli that stem out of
variety of people or things going on. People’s experiences of vitality, ingrained within their
daily practices, are often overlooked by academic, planning and design discourses. Thus,
this research proposes that any strategies to foster vitality in non-central locations should
recognise contextual and small scale solutions within long-term visions that incorporate the
voice of all actors involved in using and experiencing places.James Watt Scholarship
Strain tuning of two-dimensional quantum materials
No full textLarge scale two-dimensional (2D) moire superlattices are driving a revolution in
designer quantum materials. The strong electronic correlations in these superlattice critically depend on the periodicity and symmetry of the underlying lattices.
To date, the relative twist angle between adjacent layers has been the primary
parameter for in-situ tuning the moire lattice size.
Actively manipulating the system would allow one to control the electronic interactions that determine the emergent properties and phase diagrams of the
strongly correlated moire quantum materials. So far, the in-situ twisting of van
der Waals (vdW) layered materials is highly limited to experimental platforms
that are incompatible with state of the art quantum moire material devices. For
that reason, tuning of the electronic interaction in strongly correlated 2D moire
materials is still a missing piece in the path to solve the strong correlations puzzle.
In this thesis, I pursue a different path to achieve the in-situ tuning of the moire
lattice size and geometry. Strain tuning is established as a powerful mechanism to in situ modify not only the moire periodicity but also the symmetry
of the underlying lattice. First, a cryogenic strain tuning setup is developed to
allow reversible strain tuning of 2D materials. As a first demonstration of the
platform, the emission energy of quantum emitters in transition metal dichalcogenide (TMD) monolayers is tuned by up to 9.6 meV when ±0.52% strain is
applied. This demonstration validates the compatibility of strain tuning with
more advanced moire quantum material sample structure.
Next, an analytically exact mathematical description of the moire lattice under
arbitrary strain tuning acting on any bilayer structure is developed. This proves
the ability of moire strain tuning as a universal quantum material design platform and provides the underlying basis to analyze experimental results. To verify
the theoretical predictions, the strain tuning setup is integrated into an atomic
force microscope (AFM) to visualize the moire pattern of a TMD heterobilayer at
different strain levels. Using the newly developed experimental setup the moire
pattern is successfully imaged at different strain levels of the moire pattern. This
promising results pave the path towards future verifications of moire straintronics
as an experimental tool for the on-demand design of quantum materials
Novel image processing strategies for probing photoelectron dichroism effects in chiral molecules
No full textThe phenomenon of photoelectron circular dichroism (PECD) has revolutionised the
study of chiral molecules in the gas-phase. PECD presents itself as an asymmetry
in the photoelectron angular distribution (PAD) of chiral molecules upon photoionization with circularly polarized light, with measurable dichroism signals typically
of order ±10%. To study and extract the subtle features (including those due to
PECD effects) present in PADs, advanced experimental techniques, such as velocity
map imaging (VMI), and complementary sophisticated data-processing techniques
are required. The use of elliptically polarized laser pulses, or mixing together linear
and circular polarizations for creating the PADs further complicates the analysis
of experimental data, and often requires the use of comparatively time-consuming
tomographic imaging techniques.
This thesis investigates and develops a number of novel image processing approaches for tackling some of the challenges common to VMI experiments. This
includes exploring applications of machine learning and artificial neural networks for
solving ill-posed problems that frequently arise during the analysis of experimental
data. New tomographic reconstruction approaches are also investigated for the first
time within the context of VMI experiments. It is found that the Hankel Transform
Reconstruction (HTR) approach, in particular, has significant advantages over other
reconstruction options, and allows for PADs to be determined tomographically with
the minimum possible volume of imaging data.
These novel image processing strategies are tested by accurately reconstructing
the full three-dimensional PADs in a study of the photoelectron elliptical dichroism (PEELD) of (R)-camphor following three photon ionization with elliptically
polarized 400 nm light. This measurement revealed clear features in the PADs of
chiral molecules that have previously been thought to be negligible in other related
experiments.
Finally, the first experimental photoelectron images recorded using a laser-based
desorption source (LBD) coupled directly into a VMI spectrometer are presented.
LBD sources permit the vaporization of highly non-volatile molecules that would
otherwise be too challenging to study with gas-phase spectroscopy techniques. As
an initial test system, the multiphoton PECD of the amino-acid phenylalanine is
measured at 400 nm and shown to have a G-value of around ±7%.
Overall, the utility of photoelectron imaging experiments as a whole is anticipated to be expanded significantly as a result of the work presented here; with the
novel image processing strategies simplifying the use of more complex polarization
geometries in experiments, and the LBD technique allowing for a much wider range
of interesting molecules to be accessed in gas-phase spectroscopy measurements
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