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Modestly Modular vs. Massively Modular Approaches to Phonology
Get PDFPh. D. ThesisThis thesis considers the extent to which phonology (that is, the phonological processor) can
be considered a module of the mind. It is divided into two parts. In the first, an approach of
'modest' modularity owing to Fodor (1983) is explored. In the second, the 'massive'
modularity model, due to evolutionary psychologists in general, but Caruthers (2006a) in
particular, is examined. Whilst for Fodor (1983, 2000) the mind is only modular around its
periphery (i.e. only its input and output systems are modules), for massive modularists the
mind is modular through and through, up to and including its central capacities. The two
authors, therefore, by extension differ in their definitions of modularity: Fodor (1983, 2000)
sees 'informational encapsulation' as being essential to modularity, whereas for Carruthers
(2006) domain specificity is much more important. The thesis concludes that whether
phonology is a module or not then depends on the definition of modularity, for although a
substance-free phonology which has no phonetic grounding could count as strong evidence
for the informational encapsulation (and therefore the modularity) of phonology by Fodor's
(1983) standards, some aphasiology data has shown that semantic treatments can remediate
phonological word finding difficulties in aphasia, which would be indicative that phonology
is not domain-specific, and therefore amodular in the terms of massive modularists like
Carruthers (2006a).1 In order to answer whether phonology is modular, then, we must first
define, once and for all, what modularity (and indeed phonology) means. Until then, the
debate remains, and so does my resolve to settle it.Arts and Humanities Research Council, Northern Bridge Doctoral Training
Partnershi
Characterising the Role of Mitochondrial Dysfunction in Ageing Liver Regeneration and Inflammation
Get PDFPh. D. Thesis.Ageing is a major risk factor for chronic liver disease in which reduced regeneration and age-associated chronic inflammation or “inflammageing” is observed. In ageing, mitochondrial respiratory chain dysfunction is shown to be a key arbitrator of the process, accruing somatic mitochondrial DNA (mtDNA) mutations with increasing time. Mechanisms linking these themes remain elusive; however, respiratory dysfunction is thought to be important in excess ROS production and apoptosis. Knock-in mitochondrial replicase γ (PolgA) mice are known to recapitulate some progeroid and phenotypic features of human ageing as a result of clonally expanded somatic mtDNA mutations. Basally whilst PolgA+/mut and PolgAmut/mut ageing mice livers was shown to be histologically normal, immunohistological analysis of tissues revealed reduced hepatocellular turnover in the presence of increasing mitochondrial respiratory deficiency. This proliferative defect was attributed to mitochondrial dysfunction within the liver parenchyma and specifically hepatocytes, observing reduced complex I expression. Subsequent subjection to mechanical stress by means of two-thirds partial hepatectomy in PolgA+/mut and PolgA+/mut mice also showed a blunted proliferative response. Additionally, accelerating ageing, mitochondrial dysfunction and downstream ROS production is linked to oxidative stress and altered proinflammatory signalling. Indeed, this study of PolgA+/mut and PolgAmut/mut mice reveals skewing towards a proinflammatory environment. Analysis revealed increased honing of neutrophils within the liver that when stimulated, releases increased amounts of ROS. Such a proinflammatory phenotype appears secondary to the proliferative defect, in which the PolgAmut/mut liver following exposure to acute oxidative CCl4 stress revealed delayed regeneration and cell cycle p16 induction, as well as a failure to clear proinflammatory immune cells. Observations coincided with increasing induction of mitochondrial dysfunction and additional compensatory mechanisms of mitochondrial and antioxidant gene expression. The findings of this thesis suggests that complex I mitochondrial respiratory dysfunction plays a role in ageing hepatocellular regeneration, with ETC deficiency having further roles in regulating proinflammatory cell signalling. Dissecting the role of respiratory dysfunction in liver homeostasis and regeneration would enable understanding for therapeutic intervention in the context of ageing liver disease.MRC and Barbour Foundatio
Design of hybrid photo-voltaic/thermal solar systems and performance analysis for residential building case studies
Get PDFPh. D. Thesis.PV/T systems (Photovoltaic/Thermal Systems) is a hybrid assembly of PV and solar thermal collector technology and generates both electric and heat energy. Over the past three decades, various numerical analysis was conducted on PV/T systems under steady-state, quasi-dynamic state and dynamic state. It was realised that a set of factors affected the performance of the PV/T. However, a lack of standard for the PV/T, combined with limited experimental data to assess the variation in operating performance with respect to all the affecting factors is low.
The aim of this research is to study and model the dynamic behaviour of PV/T systems while identifying all the contributing factors responsible for its performance at any location. These factors are then investigated further to enable an accurate working model for application in residential buildings. The dynamic model that can identify the performance, efficiency, and impact of various factors for the given PV/T system was proposed and validated based on the experimental data and three different case studies were chosen based at three different locations(Newcastle, Lisbon and Cochin).
The main methodology chosen here was by solving the energy balance equations using the RK4 method in MATLAB which is supported by experimental results at real-time conditions in Newcastle with error of 4.2%. It was found that there is a significant improvement in the efficiency of at least 3% when compared to a real-time PV and solar collector unit in Portugal. The model was designed to supply load-demand for two residential cases (4-bed domestic house in Newcastle and Cochin). An exergy analysis was conducted to find the feasibility of these simulated models. The life-cycle cost efficiency for the case study in Newcastle was found to be 10.6% while in Cochin the life cycle cost efficiency was found to be at 23.2% with respect to exergy. The simulated model thus indicates that the exergy from Cochin is more feasible than from the system in Newcastle for the case studies considered in their respective locations.
Employing this model, the performance effect of various parameters can be established, an improved system can be designed and applied for residential buildings. This model can also be used as an indicator to comprehend PV/T performance based on location and thus, can act as a rudimentary support for PV/T standardisation
Improved modelling of disperse multi-phase transport based on numerical simulation and PDF analysis
Get PDFPh. D. Thesis.In this work probability density function (PDF) models are used as a method for
studying the statistical distribution of particles in turbulent flows, which is of interest
in many industrial and environmental processes. This approach involves derivation of
a transport equation for describing the evolution of the joint PDF of particle variables.
In different flow configurations the PDF approach identifies various contributions to
the particle phase mass flux that act as additional drift and diffusion terms. These
terms, which are critical in the formulation of two-fluid models, require closure. In
order to evaluate the effect of the different flux contributions arising in the various
flow configurations, these terms are considered in the context of both homogeneous
and inhomogeneous flows. In the case of homogeneous flows the enhancement of the
settling rate of inertial particles under an applied body force, specifically gravity, is
investigated. Inhomogeneous turbulence is used to study the clustering of particles in
a framework associated with the behaviour of particle pair dynamics in homogeneous
flows. Existing closures based on simple local approximations are shown to neglect the
contributions of interest to the particle phase mass flux, and an improved methodology is proposed which takes into account underlying physical mechanisms behind the
observed behaviour, and consists of modelling various correlations that arise from the
PDF formulation. The performance of this closure strategy is evaluated making use
of particle trajectory simulations in a synthetic flow field generated using Kinematic
Simulation (KS). The Eulerian two-point, two-time fluctuating velocity correlations
for the continuous phase are central to the modelling, and these are determined in the
specification of the flow field. Similarly the particle response tensor to perturbations in
the continuous phase is computed allowing for exact evaluation of the unclosed terms.
A linear drag law is used in the particle equation of motion, and the influence of both
Stokes number and applied body forces on the increase in particle settling rate and
clustering is investigated. In agreement with previous work it is seen that the mechanism responsible for these effects can be quantified in terms of the preferential sampling
of strain over rotation by inertial particles due to interaction with the structures in the
flow field.Newcastle Universit
The biochemistry of algal bioactives : their role in modulation of digestive processes
Get PDFPh. D. ThesisObesity is a serious global threat to public health causing serious chronic metabolic diseases. The drug Orlistat has been used for obesity treatment; however, orlistat causes unpleasant gastrointestinal side-effects. Recent research has investigated bioactive compounds from seaweeds, like alginate, as pancreatic lipase inhibitors to modulate fat digestion and reduce caloric intake. Previous work has shown that certain alginates can inhibit pancreatic lipase activity in vitro by up to 72%.
The aim of this thesis is to investigate the effect of alginate on lipase activity in vitro, using three different approaches: turbidimetric assay, a kinetic assay and a synthetic model gut system.
The turbidimetric assay for pancreatic lipase showed alginates can inhibit pancreatic lipase, with the level of inhibition depending on alginate structure and concentration. Alginate with a high content of guluronate residues can inhibit pancreatic lipase activity more than alginate rich in mannuronate residues.
Kinetic analysis showed that alginates act as mixed inhibitors that can bind to both the free enzyme and the enzyme-substrate complex.
Alginate passed through the gastric phase of the synthetic model gut reduced glyceryl trioctanoate digestion, but not the digestion of olive or sunflower oil. However, alginate added at the small intestinal phase reduced olive oil digestion. The regulatory effect of alginate was affected by gastric pH resulting in gel formation and precipitation, reducing or preventing the release of free alginate and reducing lipase inhibition.
Alginate bread was digestible within the synthetic model with most alginate release occurring in the small intestinal phase. Alginate incorporated into bread did not reduce fat digestion, which may be due to alginate fragmentation resulting from high temperatures during the cooking process.
The capacity of unfragmented alginates to inhibit pancreatic lipase activity in vitro supports future investigations of alginate in vivo as a pancreatic lipase inhibitor to reduce fat digestion and absorption and hence, treat obesity.Tabuk Universit
Non-canonical RNA capping by DNA-dependent RNA polymerases & screen for bacteriophage regulators of mycobacterium smegmatis transcription
Get PDFPhD ThesisIn the process of gene expression, all living cells synthesise RNA. RNA is polymerised from nucleotide
monomers in dependence of a complementary sequence on a DNA template, a gene. This is done by
DNA-dependent RNA Polymerase (RNAP) and is called transcription.
Previously, it was believed that only eukaryotic RNA can be 5’-“capped”. The 5’-cap in eukaryotes is
attached post-transcriptionally and serves several functions in RNA metabolism and in translation
(process of protein synthesis from an RNA template). Recently, a cap was found on bacterial RNA. The
bacterial cap is not a modified canonical nucleotide (like the methylated guanosine cap of eukaryotes),
but consists of small metabolites or cell wall precursors which are covalently bound to 5’-RNA. This
thesis investigates how bacterial RNAP incorporates the non-canonical initiating nucleotide (NCIN)-
cap and discusses structural determinants of NCIN-capping of both RNAP enzyme and template DNA.
RNAP accepts the cofactor and cell wall precursor as initiating substrate due to the free 3’-hydroyl group
of the nucleotide moiety of the molecule. Functional moieties such as nicotinamide ribose or riboflavin
on the 5’-end of the nucleotide ribose are bound as substrate by wiltype RNAP catalytic centre and RNA
exit channel, and do not interact with upstream promoter regions. However, larger nucleotide-containing
molecules such as uridine diphosphate N-acetylmuramic acid pentapeptide are inefficiently incorporated
due to sigma subunit of RNAP.
We further show that primase, RNA-polymerase of replication, incorporates NCIN into primer RNA
and explore potential downstream effects on replication. DNA Polymerase I which replaces primer RNA
with DNA, is differentially affected by 5’-cofactors on primer RNA.
In the bigger picture, NCIN-caps as extensions of RNA primary structure might have a variety of
physiological consequences, which are as of yet uncertain, but extensively discussed in this thesis. We
argue that RNA stability, translation, localisation, and activity of regulatory RNA might be affected.
RNA synthesis regulation in bacteria makes a fantastic target for drug development, as the cellular
machineries of prokaryotes and eukaryotes differ. Also bacteria-infecting viruses, or bacteriophages, are
often reported to interfere with host transcription in order to monopolise cellular resources in favour of
their own gene expression and replication. We propose that studying the mechanisms by which
bacteriophages hijack host gene expression could lead to the discovery or development of new
antimicrobials. In order to investigate novel aspects of transcription regulation, we outline a
methodology to study how bacteriophages regulate host transcription in mycobacteria. This bacterial
family includes today’s most deadly bacterial pathogen, Mycobacterium tuberculosis. At the example
of mycobacteriophage D29 gene product Gp53, we show that the protocol can be used to find new
inhibitors of bacterial transcription
Repainting the Pitmen : The Ashington Art Group & Robert Lyon - Rethinking Legacy through Archive and Practice
Get PDFPh. D. ThesisThe Ashington Group’s paintings are a celebrated historical record of a working
community. However, central narratives based on limited accounts and partial
knowledge of their technical methods and materials, have led to arguably simplistic
interpretations and misleading characterisations, both through previous curatorial
approaches and popular media, including Lee Hall’s play, The Pitmen Painters.
Using three distinct methodologies - archival research, curatorial and creative
practices, my research challenges dominant narratives about the Group’s intentions,
methods, output and legacy.
What new insights can be gained by the study of the pedagogical approach of tutor
Robert Lyon? Archival research and close analysis of Lyon’s MA thesis (previously
believed lost), informed by my deep knowledge of painting practices, provided a new
basis to interrogate established texts and ideas.
How can enhancing the Ashington Group public display better reflect their inherent
criticality, creative motivation and material sophistication, thereby improving
understanding? A curatorial project and new exhibition, Pitmen Painters Unseen,
identified and gathered previously un-exhibited work, addressed incomplete
narratives that exists within the Permanent Collection at Woodhorn Museum, and in
combination, presented the most comprehensive exhibition of Ashington Group
works ever staged. Expanding the range of publically available material reveals that,
whilst resolutely amateur, the Group demonstrated a sophisticated self-awareness,
actively responding to their own changing history and geography.
Can this increased understanding meaningfully inform contemporary painting?
Drawing upon innovative painting and psychogeographical practices, my major new
body of work, The Ashington Paintings, investigates the changed landscape of a
common geography. It engages with the Permanent Collection, its construction and
shared longitudinal study of the locale, and provides a neoteric position on how
contemporary practice can have an informed, discursive relationship with historical
collections.
The Ashington Group can, I conclude, be critically re-evaluated as a responsive and
self-reflexive group of artists, capable of informing contemporary practice.Arts and Humanities Research Council (AHRC
The management of the lightweight piglets from modern pig systems
Get PDFPhD ThesisThe management of lightweight pigs that have resulted from increases in sow prolificacy are a
major challenge for modern pig systems. The overall aim of this thesis was to develop
intervention strategies that improve the performance of light piglets without penalising heavy
piglets, with the pre- and immediate post-weaning period being the most critical windows for
intervention.
In the first experiment (Chapter 2) creation of litter uniformity pre-weaning optimized the
performance of piglets born lightweight, with long term benefits up to slaughter; heavy piglets
on the other hand were penalized by this strategy. Despite heavy piglet efforts to compensate
for insufficient milk intake by increasing creep feed intake, this was insufficient for achieving
similar growths to heavy piglets kept in mixed litters. That being said, piglets born heavy ate
high amounts of creep feed whereas piglets born light hardly consumed any creep feed.
In Chapter 3, it shown that irrespective of birth weight mid parity sows were identified as best
foster sows. Their piglets were weaned heavy, whilst having eaten high amounts of creep feed.
Second parity sows also weaned heavy piglets, but due to piglet low creep feed intake they were
unable to maintain this weight advantage post-weaning. Despite the high creep feed intake of
primiparous sow reared piglets, these piglets were weaned light and remained light postweaning.
Lightweight piglets did not seem to benefit from an amino acid enriched post-weaning starter
regime (Chapter 4). Although birth weight is still commonly used as indicator for identifying
runt piglets, not all light piglets are destined to remain light. In fact, piglet shape at birth such
as, length and head circumferences in relation to birth weight, seemed better predictors of postnatal
growth.
Chapter 5 evaluated the effect of weaning age, weaning weight and an increased allowance of
nursery diets on the performance of piglets through 5 months of age. The results suggested that
an enhanced allowance of the nursery diets was beneficial, but that delayed weaning may yield
long term benefits for piglets weaned lightweight.
The data from this thesis provide novel information and implications for the management of
lightweight piglets. Some lightweight piglets are able to improve their post-natal performance
and creating the optimal environment such as litter uniformity, rearing them by mid parity sows
and weaning later will be beneficial to them.Agriculture & Horticulture Development Board (AHDB) Pork and
Primary Diet
An appreciative exploration of what works to enhance the wellbeing of staff working in a special education school
Get PDFD. App. Ed. Psy. ThesisThis document includes three key sections; a systematic literature review, an empirical research study and a bridging document (linking the other two documents). Overall this project seeks to explore ‘what works’ to enhance the wellbeing of staff working in special education schools.
The first chapter, the systematic literature review, critically examines the literature surrounding special educational teacher burnout. The review is guided by recommendations from Petticrew and Roberts (2006). Eight pieces of research literature are found to meet the inclusion criteria and are consequently used within the review. A process of textual narrative synthesis is used to inform synthesis of the studies. Themes are identified across the studies and subsequently, divided into two sub-categories; risk factors and protective factors. Within the first category, risk factors, the following themes were apparent: role conflict and role ambiguity; workload manageability; self-esteem, self-efficacy and classroom management efficacy; and perceived stress. Within the second category, protective factors, the following themes were apparent: perceived support, including the type of support and where the support came from; leadership style; building relationships with students; coping strategies; career professional development; and overall happiness and job satisfaction. Based on findings from the literature review, the empirical research project seeks to explore the organisational factors enhancing staff wellbeing in a special education setting. An empirical research project in Chapter Three, draws upon appreciative inquiry (Cooperrider, Whitney, & Stavros, 2003) to explore the factors enhancing their wellbeing. Inductive thematic analysis using a hybrid of semantic and latent coding is used to analyse the data (Braun & Clarke, 2006, 2013; Willig, 2013). Five organisational factors including leadership; having a shared goal and understanding; supportive structures being in place; staff feeling supported; and the adoption of a person-centred approach are determined to enhance the wellbeing of staff within the school. Links are then made to the wider literature, with particular exploration of ‘professional learning communities’ (PLCs). The project closes by considering the implications for Educational Psychologists looking to support staff wellbeing within schools. These chapters are linked by a bridging document – Chapter Two - which explores the research journey including consideration of the philosophical assumptions underpinning and the influence these may have had on the empirical research project
Modification of the molten carbonate in dual-phase membranes for improved carbon dioxide separation
Get PDFPh. D. ThesisSolid metal and metal oxide supports for high-temperature dual-phase molten salt membranes often contain high-cost metals such as samarium, cobalt or silver. These metals are used due to their oxide and/or electron-conductive properties, which assist in carbon dioxide transport by enhancing the rate of carbonate ion formation at the feed-side surface. A cheaper alternative approach would be to use a low-cost, abundant high-temperature stable ceramic support, such as alumina, and improve membrane performance by using small quantities of metals to modify or add functionality to the membrane.
First, CO2 release from the permeate-side surface was found to be slower than the uptake of CO2 on the feed-side surface. Therefore, two different doping methods were explored to improve the rate of CO2 release from the permeate side. However, due to difficulties with solubility and precipitation, both approaches proved unsuccessful. To navigate around these issues, an effective dopant would need to still provide functionality after precipitation, one such material is silver, as it maintains its electron conductivity after precipitation from molten carbonate. Therefore, by using silver as the dopant, precipitation was used advantageously to coat the walls of the support to produce self-forming pathways that contributes to the support’s functionality. The molten carbonate was used as a carrier to redistribute silver that was doped into the membrane using multiple controlled techniques. Due to the concentration gradient across the dual-phase membrane, the silver was redistributed to form electron-conducting pathways that span the cross-section of the membrane. This process was performed in-situ during permeation and transformed a low-flux alumina supported membrane (Al2O3-MC) into a high-flux, low-silver content alumina/silver supported membrane (Ag/Al2O3-MC).
The self-forming Ag/Al2O3-MC membrane presented in this thesis provided a CO2 flux of 1.25 mL min-1 cm-2 at 650°C. This flux is higher than any oxide or electron-conducting supported membrane at the same temperature while using a CO2 and O2 feed or CO2 alone. Furthermore, when normalising the flux to account for gas feed partial pressure, membrane thickness and amount of silver used (mol m-1 s-1 Pa-1 mol Ag-1), the Ag/Al2O3-MC membrane had a permeability per mol of silver one order of magnitude higher than silver-supported membranes in the literature. The membrane also demonstrated stability at temperatures exceeding 650°C, where silver-supported membranes have been known to suffer as a result of carbonate retention issues. Computed tomography investigations indicated that could be due to silver not coating the entire pore wall. The Ag/Al2O3-MC membrane reached a permeance and permeability in the range reported as required for economically competitive carbon capture.Newcastle University EPSRC DT