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Exploring stakeholders’ views on the Change4Life ‘Sugar Smart’ campaign and school food to improve children’s diets: two qualitative studies
Get PDFPh. D. ThesisThere is a current childhood obesity pandemic and a high prevalence of dental
caries amongst children worldwide. This thesis comprises two studies which provide
an in-depth qualitative exploration of stakeholders’ views on the impact of the
national Change4Life ‘Sugar Smart’ campaign, and the influence of school food on
children’s diets in Newcastle upon Tyne.
In 2017, twenty-seven telephone interviews were conducted with parents, one-year
post ‘Sugar Smart’ campaign. Key findings were: a reported raised awareness of
child sugars intake by parents and children; ‘hidden sugars’ were a barrier to
reducing sugars intake; and, reported household shopping changes including
reduced purchasing of ‘sugary’ drinks and breakfast cereals. The national campaign
was helpful in raising awareness of the impacts of Free Sugars, one-year postcampaign. However, a more integrated approach is needed to increase the impact
and sustainability of future health marketing campaigns.
A number of parents who participated in the ‘Sugar Smart’ campaign evaluation
reported a difficulty in reducing their child’s Free Sugars intake when their children
were at school. This finding warranted further research, therefore, a second study
was designed to explore stakeholder views on school food contribution to the diets of
children. Three schools in Newcastle upon Tyne were recruited. Focus groups were
conducted with parents and children. Head teachers, canteen staff and employees of
Newcastle City Council who are involved in school food provision were interviewed.
Identified themes included puddings being a controversial addition to school dinners,
a preference for school dinners over packed lunches, and the ability of school
dinners to encourage children to try new foods. Communication between
stakeholders needs to be improved, and clearer, more consistent messages about
the importance of nutritionally balanced school meals are needed.
This research highlights that a diverse range of initiatives are needed across
different settings to improve children’s diets. A single approach to achieving positive
improvement is unlikely to be successful. To ensure the environments which children
interact with allow easy and accessible healthy food and drink choices, there is a
need for change within legislation and policy, as well as the development of whole
school approaches. All stakeholders involved should prioritise the health of children
and work together to achieve a positive improvement of children’s diet
Studying polyoxometalates for application in redox flow batteries
Get PDFPhD ThesisEnergy storage is important to an energy sector in which renewable energy sources become
more prevalent and the use of energy from fossil fuels is minimised. As energy from
renewable sources is produced intermittently (e.g. from wind and solar photovoltaic systems),
energy storage can be used to stabilise these energy sources by storing excess energy
produced during times of low demand and releasing it later.
Redox Flow Batteries (RFBs), a type of secondary battery, are an energy storage
technology that is of interest to both large-scale energy storage and smaller off-grid energy
storage systems. RFBs have differences in operation compared to other secondary batteries.
For instance, all of the active material of an RFB is dissolved in the electrolytes and no
plating or intercalation reactions occur at the electrodes during charge and discharge. Further,
the electrolytes are stored in external tanks and transported to the cells of an RFB by using
pumps. This decouples the power and energy content of an RFB; power and energy can be
adjusted independently by varying the size of the cell stack or the volume of electrolyte.
In RFB research, a common endeavour is the investigation of active materials that
could target some of the limitations of the most mature RFB, the all-vanadium RFB, which
uses vanadium ions as the active species. Polyoxometalates (POMs) are one type of
compound that have been studied as RFB active materials. POMs are anionic metal-oxygen
clusters containing early transition metals, termed the addenda atoms of the POM, which are
often tungsten, molybdenum and vanadium. These elements can exhibit reversible redox
reactions when incorporated into a POM. An additional element, such as silicon or
phosphorus, is sometimes present in the core of a POM and is termed a heteroatom.
In this work, aspects of POMs for application in symmetric and asymmetric RFBs are
investigated. Symmetric RFBs use the same active species in the positive and negative halfcell whereas asymmetric RFBs use a different species in each half-cell. [SiV3W9O40]
7-
, a
mixed-addenda POM containing tungsten and vanadium, is studied as an active species for a
symmetric RFB. Selected electrochemical properties of two POMs containing one type of
addenda atom but a different heteroatom, [SiW12O40]
4-
and [CoW12O40]
6-
, are also investigated
in relation to their application as the active material in the negative electrolyte of an
asymmetric RFB.
In symmetric flow cell testing of [SiV3W9O40]
7-
, coulombic efficiencies were >98%
with 65% of the theoretical capacity of the battery accessed and a capacity fade of 2.7% over
50 cycles observed. Analysis of cycled [SiV3W9O40]
7-
electrolytes did not indicate
decomposition had occurred, indicating stability of [SiV3W9O40]
7-
to the charge/discharge
testing conditions in this study. In a study of the kinetics of the electron transfer o
The Economic Effects of Childhood Speech and Language Difficulties: A Cross-Cohort Quantitative Life Course Analysis
Get PDFPh. D. Thesis.Introduction
Early vocabulary and speech development predict poorer broader childhood skills, educational attainment, mental health, and employment. However, little is known beyond early adulthood about how language relates to income, non-cognitive skills, or physical health.
Aims
The thesis aims to utilise historical data to highlight the broad and enduring impact of early communication over the life course. Appropriate, evidence-based recommendations are established for research and clinical practice.
Methodology
Two datasets were selected, capable of modelling the importance of early communication skills on life chances. The Newcastle Thousand Families Study (1947) incorporates novel health visitor observation data from age two to seven of 881 children, identifying 161 with Speech, Language and Communication Needs. The British Cohort Study (1970) complements this analysis with a national dataset of thousands of children, containing a continuous assessment of receptive vocabulary at age five. Regression, mediation, and counter-factual econometric methods (Oaxaca-Blinder Decomposition and Regression Discontinuity Design) are utilised to maximise the value in the historical data.
Findings
SLCN is associated with introverted personality traits, and a reduced tendency to enjoy new experiences in later adulthood. Lower earnings and health were observed at age 50 but not age 62.
Mediation analysis confirms the existence of a direct relationship between early receptive vocabulary and later earnings across adulthood. No significant mediation effect was observed through education or non-cognitive skills after accounting for this direct effect.
However, when comparing income differences between high and low vocabulary groups (no direct effect of vocabulary), higher levels of educational attainment and cognitive skills were found in the high vocabulary group on average, explaining most of the observed group
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differences in income. Returns to these variables are not statistically different between vocabulary groups, implying that vocabulary does not moderate the importance of known drivers of income. In summary, it is disadvantage in early years rather than discrimination in adulthood which explains the income gap.
Furthermore, whilst vocabulary scores predict a range of functional outcomes, this is not true over narrow thresholds. Small differences in language scores do not predict outcomes, regardless of the placement of the threshold, suggesting that thresholds are an unreliable method of identifying functional language disorders. Therefore, strictly applied thresholds should be removed from clinical diagnoses, and academic research should reduce its reliance on unsupported distinctions.
Conclusion
Varying methodological approaches and data enable the illustration of substantial positive associations between early verbal communication skills and a range of previously unmeasured lifelong outcomes.The Economic and Social Research Counci
The transformative potential of philosophical dialogue: space for children and young people to explore their multi-storied lives
Get PDFDAppEdPsy ThesisThis thesis explores experiences of philosophical dialogic inquiry as a pedagogical
approach with children and young people (CYP), for example, the use of Philosophy
for Children (P4C). It contains four chapters: a systematic literature review, a critique
of ethical and methodological choices, an empirical research project and a reflexive
chapter, which considers personal and professional implications of the thesis.
Chapter 1: How do children and young people experience the process of
philosophical dialogic inquiry and the wider implications of this pedagogical
approach?
This systematic literature review explores children and young people’s (CYP’s)
experiences of philosophical dialogic inquiry, a pedagogical approach that invites
CYP to engage in critical thought and discuss a philosophical topic together. A metaethnography was used as a process to search and synthesise qualitative literature.
Five papers were selected and reviewed. The key themes identified were features of
a dialogic process, experiences of learning as a sociocultural experience and,
reconstructed perceptions of the self, others, and learning. The influence of the
context on the experiences of CYP was also identified as a critical theme. A line of
argument was expressed in a visual form to illustrate the relationship of these themes
to one and other. The review highlights the momentary experience of engaging in a
dialogic process and wider implications for CYP, such as, engagement in dialogue
outside of the school context and shifts in perceptions. Teacher accounts in the
synthesised research also illustrated how philosophical dialogic inquiry can challenge
adults’ perceptions of CYP and what they are capable of. This may illustrate the
potential for transformative change for CYP and adults.
Chapter 2: An ethical and methodological critique
This chapter explores ethical and methodological considerations during the
development of the research project outlined in Chapter Three. The philosophical
orientation of the research was social constructionism; therefore, the construction of
language and power were critically considered throughout. The research was
informed by participatory principles and narrative inquiry. Due to the COVID-19
pandemic, the research was facilitated virtually. Thus, virtual methodologies, and the
associated implications of this, were continually reflected upon.
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Relational ethicality guided the process of the research as there was ongoing
attunement to interpersonal dynamics. This is arguably an aspect of quality and
rigour in qualitative research (Groundwater‐Smith & Mockler, 2007).
Chapter 3: A narrative inquiry with autistic young people and teachers in their
school: how are the narratives they have constructed about themselves and
their experiences woven and explored during philosophical dialogue?
The purpose of this empirical research is to understand how stories can be
constructed and enacted in P4C. The project was undertaken in a specialist school /
sixth form in the North East of England and adopted a qualitative approach. Autistic
CYP, and teaching staff participated in the construction of the research approach,
analysis, and dissemination decisions. Virtual semi-structured interviews were carried
out to explore biographical stories and experiential stories. The interviews were
constructed and analysed using Narrative Orientated Inquiry, Collocation Analysis
and Critical Narrative Analysis. Findings are discussed with regards to the
connections in the rich life stories and experiential stories shared by an individual,
this aims to address how narratives can be woven and explored during a P4C
process. By developing an understanding of the transformative potential of
philosophical dialogue, I hope this will inform holistic understandings of CYP, and
creative pedagogical practice.
Chapter 4: How did I shape the research and how did the research shape me?
Personal and professional implications.
This chapter explores personal and professional implications of the research project
outlined in Chapter Three. Engaging in participatory processes had implications on
how I negotiated a relational dynamic when working alongside CYP and teachers.
The use of narrative psychology was therapeutic and transformational, this
consolidated narrative ways of ‘being’ as a key aspect of my professional practice.
The stories shared in the research also prompted me to rethink pedagogy and how I
could construct space for shared reflection on pedagogical approaches, and the
underpinning philosophical principles, in education. Unpicking and understanding
moments of reflexivity during the research has highlighted my key values as a
person, researcher, and Educational Psychologist (EP)
Integrating life cycle assessment with genetic selection to reduce the environmental impacts of pig production
Get PDFPhD ThesisSusPig project, funded through the Horizon 2020
ERA-NET scheme and through DEFR
Validating Next Generation Therapeutics and Targets in Castrate-Resistant Prostate Cancer
Get PDFPhD ThesisAberrant androgen receptor (AR) signalling is a key driver of prostate cancer (PC) manifestation and
progression. Therefore, therapeutic intervention has focused on interrupting the AR signalling axis using
androgen deprivation strategies and direct receptor antagonists, such as enzalutamide, collectively
termed hormone therapy. Despite initial efficacy, hormone therapy ultimately fails due to a cohort of
resistance mechanisms which enable reactivation of AR signalling and PC progression to a more aggressive
form called castrate resistant prostate cancer (CRPC). Clinically, CRPC presents as a disease with minimal
effective treatment options and therefore, new targets and therapeutics are required to improve patient
outcome.
Of the characterised mechanisms of hormone therapy resistance that enable progression to CRPC point
mutations within the ligand binding domain of the AR enhance promiscuity of the receptor to promote
binding and activation by alternative ligands, including enzalutamide. Crucially, next generation
compounds are currently in development to improve targeting of clinically-relevant mutated forms of the
AR. Other resistance mechanisms include androgen bypass in which AR is controlled by other signalling
pathways, including kinase cascades such as PI3K-AKT. Consistent with this phenomenon the kinase SGK1
has been linked to AR signalling and has been postulated to be a potential therapeutic target in CRPC.
The aims of this study were to:
• better understand the mechanism of action and efficacy of the newly developed JNJ-Pan-AR
compound, which is a non-clinically-relevant derivative of JNJ-63576253, across a cohort of
CRPC relevant cell lines
• validate SGK1 as a therapeutic target and understand whether SGK1 regulates AR activity.
This study showed the JNJ-Pan-AR has antagonistic activity comparable to enzalutamide in CRPC cell lines
expressing wild-type AR, and significantly outperforms enzalutamide in a clinically-relevant ARF877L point
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mutant-expressing cell line. JNJ-Pan-AR mediates these effects by binding AR and preventing nuclear
translocation and enrichment at key cis-regulatory elements of AR-target genes. For the second aim of
the project, it was concluded that SGK1 knockdown significantly reduces proliferation of a cohort of CRPC
cell lines, and significantly effects a subset of AR target genes. However, these results were not emulated
using SGK1 inhibitors previously used in the literature (GSK650394), with publicly available kinase screen
data suggesting that these compounds are highly un-selective. Gene set enrichment analysis (GSEA) on
RNASeq data suggested that SGK1 drives a cohort of genes with a similarity to neuroendocrine prostate
cancer (NEPC) associated pathways MYC and mTOR. In all, the work has helped define the mechanism of
action of a novel next generation anti-androgen which will be of value for understanding which patients
would benefit from the clinical candidate compound JNJ-63576253. Furthermore, although the evidence
suggests that SGK1 is not strongly implicated in AR regulation, its depletion rather than kinase inactivation
using a selective inhibitor impacts prostate cell proliferation suggesting a potential scaffolding role of
SGK1 in controlling cell fate. Future studies are required to help define this phenomenon
Computational modelling of the spread of tree disease through forests
Get PDFPhD ThesisThe impact of infectious tree diseases, such as Ash dieback, are wide-ranging: economic
losses are estimated to be in the region of billions of pounds, for example with the cost
of Ash dieback to the UK estimated to be £15 billion over the next century [1], risking
thousands of jobs. Ecological losses can extend beyond the affected tree species to many
dependent species, at a time when concern over the precariousness of many species is
mounting; the loss of some tree species can also lead to desertification and permanent
habitat loss. Palm trees, which are threatened by Bayoud disease, in particular can help
to prevent desertification [2].
In order to control outbreaks of infections and mitigate this damage, it is desirable to
develop reliable warning signals, which can indicate when a localised outbreak is likely to
become an epidemic. Outbreak events can also be predicted or prevented by identifying
characteristics, such as planting density or homogeneity, which may make a forest especially
vulnerable or resilient. However, the possibility of identifying these through experiment is
limited: tree diseases typically spread over long time scales, it is hard to control the relevant
parameters, for example, maintaining a particular density of trees without continual human
interference, and the areas of land required would be considerable. In this thesis, we will
further develop existing mathematical models for disease spreading while making a broad
examination of the effect of the parameters involved, in particular, the tree density, the
infection rate and effective distance, and the uniformity of the forestscapes.
Our approach uses a lattice-based model, which combines a compartmental model of
infection with a spatial component. Each lattice point represents either a tree or an empty
space. We start with an infection with local interactions, such that an infected tree can only
transmit the disease to its nearest neighbours. We consider two types of neighbourhoods:
von Neumann and Moore, and quantify the observed dynamics by measuring the spreading
velocity of the disease. As the forestscape density increases, we see a transition from local
confinement to widespread outbreak at a critical density. The critical density is consistent
with the percolation threshold, that is, the point at which the domain is spanned by a
single connected cluster. We also further investigate an established framework of early
warning signals such as the standard deviation, skewness and kurtosis of the velocity to
predict the occurrence of the transition to the outbreak regime. Further measures, such as
the mortality, also indicate a critical shift at the same critical density.
Previous work has focused on homogeneous forests, but this is not very representative of
real forests, which frequently exhibit large scale features, such as man-made structures, or a
natural clustering of trees. We develop an algorithm for generating forests with clustering,
with a single parameter governing the degree of clustering. We characterise the observed
distributions of trees in terms of Besag’s function, which captures how far a distribution is
from random at particular length scales. We also extract data on the distribution of trees
in real forests, using the Mahalanobis distance, a measure of how close the properties of
an individual are to the properties of a set, to classify cells as either containing trees or
not, and compare this to our synthetically generated data.
Using our synthetically generated clustered forestscapes in our local model, we observe
that the dynamics strongly depend on the degree of clustering. We find that an increase
in the level of tree aggregation suppresses the infection propagation. The critical density
for the transition to the epidemic is consequently shifted to higher values for clustered
forestscapes.
We then consider how the dynamics of an infection which spreads in a more realistic non local way differ from an infection which only spreads locally. We observe that, in addition
to the tree density and the degree of clustering, the dynamics are strongly influenced by the
characteristic spreading distance, with some interesting interplay between the parameters.
Measuring the spreading velocity, we again see that clustering suppresses the infection, but
as the spreading distance increases, this effect is diminished. For the non-local infection,
the transition to the epidemic regime is not clear when considering the velocity, but can
be seen in the mortality. However, it occurs at much smaller tree densities than for the
local infection. Overall, the dynamics of the infection can be remarkably altered by the
switch from local to non-local interactions, with several observed effects that are relevant
to understanding and predicting the propagation of tree diseases.King Abdulaziz University and the government of Saudi Arabia
Robust optimisation of dry port network design in the container shipping industry under uncertainty
Get PDFPhD ThesisThe concept of dry port has attracted the attention of many researchers in the field of containerised
transport industry over the past few decades. Previous research on dry port container network
design has dealt with decision-making at different levels in an isolated manner. The purpose of
this research is to develop a decision-making tool based on mathematical programming models to
integrate strategic level decisions with operational level decisions. In this context, the strategic
level decision making comprises the number and location of dry ports, the allocation of customers
demand, and the provision of arcs between dry ports and customers within the network. On the
other hand, the operational level decision making consists of containers flow, the selection of
transportation modes, empty container repositioning, and empty containers inventory control. The
containers flow decision involves the forward and backward flow of both laden and empty
containers. Several mathematical models are developed for the optimal design of dry port networks
while integrating all these decisions.
One of the key aspects that has been incorporated in this study is the inherent uncertainty of
container demands from end customers. Besides, a dynamic setting has to be adopted to consider
the inevitable periodic fluctuation of demands. In order to incorporate the abovementioned
decision-making integration with uncertain demands, several models are developed based on twostage stochastic programming approach. In the developed models, the strategic decisions are made
in the first stage while the second-stage deals with operational decisions. The models are then
solved through a robust sample average approximation approach, which is improved with the
Benders Decomposition method. Moreover, several acceleration algorithms including multi-cut
framework, knapsack inequalities, and Pareto-optimal cut scheme are applied to enhance the
solution computational time.
The proposed models are applied to a hypothetical case of dry port container network design in
North Carolina, USA. Extensive numerical experiments are conducted to validate the dry port
network design models. A large number of problem instances are employed in the numerical
experiments to certify the capability of models. The quality of generated solutions is examined via
a statistical validation procedure. The results reveal that the proposed approach can produce a
reliable dry port container network under uncertain environment. Moreover, the experimental
results underline the sensitivity of the configuration of the network to the inventory holding costs
iii
and the value of coefficients relating to model robustness and solution robustness. In addition, a
number of managerial insights are provided that may be widely used in container shipping
industry: that the optimal number of dry ports is inversely proportional to the empty container
holding costs; that multiple sourcing is preferable when there are high levels of uncertainty; that
rail tends to be better for transporting laden containers directly from seaports to customers with
road being used for empty container repositioning; service level and fill rate improve when the
design targets more robust solutions; and inventory turnover increases with high levels of holding
cost; and inventory turnover decreases with increasing robustness
Analysis of active watch data after stroke
Get PDFPhD ThesisDue to the rapid development of modern technology and the low cost of wearable
devices, a very large amount of accelerometer data has been recorded and used in many
different areas, particularly in medical research. However, the analysis of accelerometer
data is very challenging due to its complex structure, i.e., the large noise-signal ratio, the
very large amount of data and the heterogeneity in different data sets. In this thesis, we use
wavelet in a functional data analysis (FDA) framework to analyse the data and apply this
method to evaluate upper limb function after stroke, a difficult task in medical research. In
addition to the commonly used features (Preece et al., 2009; Sekine et al., 1998) based on
the wavelet energy preserving condition for accelerometer data under the discrete wavelet
transform (DWT), we propose two new types of scalar features. They extract different
types of information from the accelerometer data and use to predict upper limb function
for stroke patients. To further investigate the ‘details’ based on wavelet-domain, under a
Bayesian hierarchical model (NIG-MT), the wavelet coefficients with small values can be
eliminated properly and efficiently with negligible loss from the total information. We will
use the slide window approach and multivariate functional principal component analysis
(fPCA) based on the small DWT tree structure. This further reduces the size of the data
set and extracts the useful information from the pattern of small DWT tree structures in
wavelet-domains. Classification and regression models are developed based on the small
DWT tree structure. The models have been applied to distinguish between the different
activities in the designed data and refine the new features in free-living data to assess the
patients’ upper limb function respectively
Local communities as infrastructure for place-based mobile learning
Get PDFPh. D. Thesis.The last decade has seen a significant reconfiguration of the UK’s public services through
policies of austerity. Severe funding cuts have beenmade tomany local councils, resulting
in various services—such as the upkeep of local parks, and educational activities within
them—to be cut from some authorities’ funding altogether, with their upkeep instead relying
upon volunteerism or charges. Coinciding with an increase in the use of mobile technologies
in schools, stakeholder groups are frequently also turning to them in an effort to promote
the places they care for: attempting to engage with new audiences and promote the value of
place to younger generations.
This thesis explores the design space for mobile learning platforms which harness places
and communities as resources for both formal and informal learning, and how such technologies
can be used by stakeholders to share their knowledge and further their own agendas.
This design space is then further explored through the design, development and evaluation
of OurPlace—a mobile learning platform consisting of Android and iOS applications and
a supplementary website. Through multiple engagements, OurPlace was shown to support
community members, teachers and learners in creating, sharing and engaging with
place-based mobile learning activities through seamless learning experiences. To further
investigate how such mobile learning technologies and local resources could be effectively
used within formal education, this work also proposes a framework for ‘project-basedmobile
learning’, applying and evaluating this framework using OurPlace in three different schools
and a summer school of Travelling Showchildren, working within the unique constraints of
each.
Through a design-based research approach, this project combines findings of longitudinal
observational studies with volunteer community groups and a mix of long and short-term
case studies with schools to contribute: implications for designing digital platforms which
harness places’ existing social infrastructures as resources for civic learning; OurPlace, a
platformdesigned to harness these resources; and the introduction and demonstration of a
generalisable framework for structuring the use of such mobile learning technologies within
project-based learning, along with recommendations for its re-configuration in response to
contextual constraints