62880 research outputs found
Sort by
The mediating role of coping in the relationship between perceived health and psychological wellbeing in recurrent urinary tract infection: The rUTI Illness Process Model
Get PDFBackground: Recurrent urinary tract infection (rUTI) is associated with significant symptom and quality of life burden. Given the unique challenges in diagnostics and management, healthcare disillusionment and stigmatisation which distinguish rUTI from other urological conditions, specific identification of the key illness processes experienced by this patient population is required. This study aimed to identify the unique illness processes and perceptions that contribute to quality of life in rUTI, through perceived health status, psychological wellbeing, and coping.
Methods: An international sample of adults living with rUTI (N=389, 96.9% female) completed a cross-sectional survey comprising the following standardised questionnaires: the EuroQoL EQ-5D-5L, Patient Health Questionnaire 9 (PHQ-9), Generalised Anxiety Disorder 7 (GAD-7), Connor-Davidson Resilience Scale–10 (CD-RISC-10), Pain Catastrophising Scale (PCS). Sociodemographic characteristics were also assessed. Structural equation modelling was conducted to identify the underlying constructs which contributed to psychological wellbeing in rUTI, establishing the ‘rUTI Illness Process Model’.
Results: The positive relationship between ‘perceived health status’ and ‘psychological wellbeing’ was partially mediated by ‘rUTI coping’, after controlling for the impact of household income and age (p<.001). The model demonstrated a large effect size (R2=.81) and good local and global fit. Overall, rUTI coping skills, boosted by resilience and weakened by pain catastrophising, contribute to a significant proportion of the positive relationship between perceived health status and psychological wellbeing in rUTI. A uniquely vulnerable patient phenotype emerges from this new research, with patients who are younger and/or of lower socioeconomic status at greater risk of poorer rUTI health outcomes and psychological wellbeing, potentially requiring further support.
Conclusions: The rUTI Illness Process Model establishes the crucial need to clinically characterise the individualised illness perceptions and metacognitive strategies held by people living with rUTI, revealing that patient-centred interventions targeting illness perceptions and coping strategies require prioritisation to enhance patient outcomes and the patient experience of living with rUTI
Atomic structure of different surface terminations of polycrystalline ZnPd
Get PDFThe intermetallic compound ZnPd has been found to have desirable characteristics as a catalyst for the steam reforming of methanol. The understanding of the surface structure of ZnPd is important to optimize its catalytic behavior. However, due to the lack of bulk single-crystal samples and the complexity of characterizing surface properties in the available polycrystalline samples using common experimental techniques, all previous surface science studies of this compound have been performed on surface alloy samples formed through thin-film deposition. In this study, we present findings on the chemical and atomic structure of the surfaces of bulk polycrystalline ZnPd studied by a variety of complementary experimental techniques, including scanning tunneling microscopy (STM), x-ray photoelectron spectroscopy (XPS), low energy electron microscopy (LEEM), photoemission electron microscopy (PEEM), and microspot low-energy electron diffraction (μ-LEED). These experimental techniques, combined with density functional theory (DFT)-based thermodynamic calculations of surface free energy and detachment kinetics at the step edges, confirm that surfaces terminated by atomic layers composed of both Zn and Pd atoms are more stable than those terminated by only Zn or Pd layers. DFT calculations also demonstrate that the primary contribution to the tunneling current arises from Pd atoms, in agreement with the STM results. The formation of intermetallics at surfaces may contribute to the superior catalyst properties of ZnPd over Zn or Pd elemental counterparts
A study of hegemonic masculinity in select plays by Harold Pinter
Get PDFThis thesis expands existing scholarship on Harold Pinter by integrating perspectives from
gender studies, sociolinguistics, and performance analysis. It investigates how Pinter's
characters contribute to and perpetuate hegemonic masculinities, exploring the
consequences of challenging or maintaining gender hierarchies. Through the lens of
prototypicality threats in Pinter's text, the analysis reveals specific linguistic tools characters
employ to reinforce gender hegemonies.
In performance, Pinter’s depiction of gender inequality becomes much more overt,
and this thesis aims to recognise how contemporary audiences perceive gender and
hegemony in productions of Pinter's plays. Utilising semiotics, this study identifies dominant
characteristics of Pinter's dramatic language and how they are realised on stage. The
spectator's role in meaning production is considered by acknowledging the impact of a
political unconscious on the reception of hegemonic masculinity in contemporary
productions.
This thesis presents an original and provocative examination of Pinter's work,
contributing to previous research on gender, language, and performance. I identify distinct
hegemonies in each play and highlight consistent behaviours across Pinter's work. The
exploration of prototypicality offers an original lens for understanding gender and power
dynamics in Pinter's plays. Additionally, the study engages with contemporary productions
and their reception, shedding light on how British theatre contributes to perceptions of
gender inequality, violence, and misogyny.
Reflecting on the impact of this research, the thesis has taken Pinter scholarship in
a new direction, critically examining hegemonic masculinity and its portrayal of female
oppression. Future scholars are encouraged to maintain a critical perspective, addressing
the problematic aspects of gender hegemony in Pinter's work and exploring the
intersections with racial and xenophobic prejudice. The identification of prototypicality
threats is proposed as a valuable tool for analysing Pinter's text and aiding scholars in
understanding fluid gendered power dynamics between characters
Generalized scaling laws for the irrotational motions bordering a turbulent region
Get PDFIn turbulent free shear flows such as jets and wakes, and also in turbulent boundary layers, the turbulent region is bounded by a region of irrotational flow where the magnitude of the potential velocity fluctuations can be very high. This is particularly true close to the turbulent-nonturbulent interface layer (TNTI) that separates the regions of turbulent (rotational) and nonturbulent (irrotational) fluid motion in these flows. Previous works have shown that for distances from the TNTI x_2 much bigger than the integral scale L in the nearby turbulent region (x_2 >> L), the variance of the velocity fluctuations (i = 1,2,3) depends on the shape of the kinetic energy spectrum in the infrared region E(k) ∼ k^n [O.M. Phillips, Proc. Camb. Phil. Soc. 51, 220 (1955); Xavier et al., J. FluidMech. 918, A3 (2021)]. Using rapid distortion theory, we derive the generalized scaling laws for the potential velocity fluctuations, at distances sufficiently far from the TNTI layer, for any value of n. While the cases n = 4 (Batchelor turbulence) and n = 2 (Saffman turbulence) have been previously derived, with ~ x_2^(−4) and ~ x_2^(−3), for n = 4 and n = 2, respectively [O. M. Phillips, Proc. Camb. Phil. Soc. 51, 220 (1955); Xavier et al., J. FluidMech. 918, A3 (2021).], we extend these results by including any other value of n. In particular, we obtain ~ x_2^(-2) and ~x_2^(-4) for n = 2 and n > 4, respectively, while n = 3 yields ~ x_2^(-4) ln(x_2). These theoretical results are confirmed by direct numerical simulations of turbulent fronts evolving into an irrotational flow region in the absence of mean shear
Bringing intelligence to the edge: towards smart and adaptive residential learning healthcare systems
Get PDFIn light of an increasingly aging population, it becomes crucial to preserve good health
and independence for as extended a period as feasible. Rather than hospitalization and
placement in institutional care, individuals facing chronic illnesses or physical
limitations can benefit from the support of smart healthcare Information and
Communication Technology (ICT) solutions, right in the comfort of their own homes.
Currently, there is a shift in healthcare ICT solutions towards more balanced
approaches that integrate hospitals and homes, with the ultimate goal of transitioning
to home-centric healthcare systems in the future. However, for this evolution to
progress, it necessitates the integration of new technologies, system architectures, and
computing paradigms.
As this transformation advances towards the concept of Learning Healthcare Systems
(LHS) it brings forth fresh challenges that must be addressed to meet evolving
requirements. To enable the development of home-centric healthcare solutions it is
essential to extend the concept of LHS to personal residences by incorporating
intelligent Edge computing.
A gateway is a key component in residential healthcare systems. By enhancing its
adaptability and imbuing it with intelligence, we can elevate residential healthcare
systems to the status of Learning Healthcare Systems (LHSs), capable of making real-time decisions. To develop adaptable consumer gateways for consumer healthcare
applications, this research work outlines a set of technical requirements concerning
scalability, reliability, availability, interoperability, energy efficiency, and privacy that
need to be fulfilled before any product or service can be created.
This research work aims to provide the requirements for the innovation of a one-for-all smart adaptive consumer gateway in residential learning healthcare systems and to
influence the consumer healthcare field to consider the benefits of moving to adaptive
gateways for future developments
Exploring mucoadhesive and toxicological characteristics of novel water-soluble polymers synthesised by modifying linear polyethyleneimine with various anhydrides
Get PDFLinear polyethyleneimine (L-PEI) has been extensively used in various fields, such as
pharmaceutical formulations, gene delivery, and water treatment. Though L-PEI is
considered as a potential gene delivery vector or as a pharmaceutical excipient, the
applications of L-PEI are limited as L-PEI displays relatively high toxicity and low
biocompatibility. The secondary amine groups within L-PEI can interact with cell
membranes and the extracellular matrix, and these interactions are predominantly
electrostatically driven. Herein, we selected succinic anhydride, phthalic anhydride,
methacrylic anhydride, crotonic anhydride and maleic anhydride to modify L-PEI to improve
functionality and lower its toxicity. Firstly, L-PEI was prepared by fully hydrolyzing
commercially available poly(2-ethyl-2-oxazoline) (PEOZ, 50 kDa) and then reacted
with different anhydrides. The obtained succinylated L-PEI, phthaylated L-PEI,
methacrylated L-PEI, crotonylated L-PEI and maleylated L-PEI were fully characterized
using 1
H-NMR and FTIR spectroscopies, turbidity-pH measurements and
electrophoretic mobility. The resultant polymers (succinylated L-PEI, phthaylated L-PEI
and maleylated L-PEI) were the polyampholytes which each have an isoelectric point
(pHIEP), and two cationic polyelectrolytes methacrylated L-PEI, crotonylated L-PEI
according to their structures. Water-soluble polymers generally exhibit mucoadhesive
activity, interacting with mucin via electrostatic effects or hydrogen bonding or/and
formation of interpenetrating layer between polymers and mucus gel. Mucoadhesion
of polymers can provide significant opportunities when designing pharmaceutical
formulations, such as tablets, films, patches and gels. However, the mucoadhesive
properties of polyampholytes are rarely reported in the literature. This work thus
explored the factors affecting the mucoadhesive properties of both synthetic and
natural polyampholytes. Turbidimetric titrations and isothermal titration calorimetry
(ITC) were conducted to investigate the interactions between polyampholytes and
porcine gastric mucin in solutions. Both synthetic and natural polyampholyte
demonstrated more pronounced interactions with mucin at pH<pHIEP than at pH≥pHIEP,
where the polyampholytes are positively charged and mucin remains negatively charged.
Electrostatic effects are predominantly responsible for their mucoadhesion whilst hydrogen
bonding and hydrophobic effects have synergistic effects. A system of polyampholyte and
fluorescein isothiocyanate (FITC) coated tablets were used to assess adhesion to porcine
gastric mucosa at different pHs in essentially “static” systems. In addition, to reflecting
fluid dynamics encountered on clinical application, the polyampholytes were labelled
fluorescently and prepared in solutions to determine their retention using a
fluorescence microscopy-based flow-through assay. These ex vivo assays confirmed
that the polyampholytes exhibited superior mucoadhesive properties at pH<pHIEP. All
these studies demonstrated solution pH and pHIEP of polyampholytes are primary factors
affect mucoadhesive properties of polyampholytes, and hydrogen bonding,
hydrophobic effects, water transport, capillary forces, penetration also contribute to
mucoadhesion. To test the generalisability of these findings, the retention of
methacrylated L-PEI, crotonylated L-PEI, maleylated L-PEI and succinylated L-PEI on
bovine palpebral conjunctiva at physiological pH (pH=7.4) was assessed using a
fluorescence microscopy-based flow-through assay. Methacrylated-L-PEI and
crotonylated L-PEI exhibited strong mucoadhesive properties at pH 7.4, due to the formation
of covalent bonding between unsaturated C=C moieties within these synthetic cationic
polyelectrolytes and mucin thiol groups. Conversely, maleylated L-PEI and succinylated L-PEI were poorly-mucoadhesive since physiological pH was above their isoelectric point,
leading to electrostatic repulsion between the polyampholytes and mucin. In addition, the
contribution of amine groups within these polyelectrolytes to adhesion are minimal at pH=7.4,
where these polyelectrolytes are either non-charged or negatively charged. Toxicological
evaluation and irritation studies of the modified L-PEI derivatives were undertaken. In vivo
assays with planaria and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium
bromide (MTT) cell viability assay, and slug mucosa irritation assay suggested anhydride
modified L-PEIs alleviated the adverse toxicity effects seen for the parent L-PEI.
In summary, modification of L-PEI with organic anhydrides enhanced mucoadhesive
properties and biocompatibility of L-PEI, and reduced its toxicity, displaying great potential
of modified L-PEI derivates as novel water-soluble functional excipients for mucoadhesive
delivery systems
Enhancing the properties of liquid crystal polymers and elastomers with nano magnetic particles
Get PDFSide-chain liquid crystal polymers have been mixed with ferromagnetic particles, and the formation of a monodomain in magnetic fields studied. At relatively low concentrations, the presence of ferroparticles substantially speeds up the rate of formation of a monodomain within the magnetic field, and, at a given concentration of ferroparticles, that rate is independent of the magnetic field’s strength. In this way, the rapid formation of a monodomain is possible at magnetic field strengths far lower those required for the liquid crystal polymer alone. This is anticipated to be very helpful in the fabrication of devices based on monodomain liquid crystal elastomers. Wide-angle x-ray scattering has been used to monitor the formation of the monodomain and small-angle x-ray scattering gives some indication of the ferroparticles’ behaviour. A model is developed to explain their behaviour. The alignment properties of the ferroparticles are related to their ability to form chains under the influence of very low magnetic fields; these chains are of relatively low stability and may become disrupted after long periods of time, high magnetic fields, or high concentrations. In general, the best results for alignment were at volume fractions below 1%, and under these conditions there is the potential for producing monodomain samples with improved properties; in particular, shape changes with temperature are significantly larger as a result of improved backbone orientation. Experiments involving monodomain formation and director realignment suggest that the presence of ferroparticles results in a modification of the mechanism for alignment development, driven by the organization of the polymer backbone, as a consequence of the constraints offered by the morphology of the chains of the ferroparticles
Identifying probabilistic weather regimes targeted to a local-scale impact variable
Get PDFLarge-scale atmospheric circulation patterns, so-called weather regimes, modulate the occurrence of extreme events
such as heatwaves or extreme precipitation. In their role as mediators between long-range teleconnections and local
impacts, weather regimes have demonstrated potential in improving long-term climate projections as well as sub-seasonal to seasonal forecasts. However, existing methods for identifying weather regimes are not specifically designed to capture the relevant physical processes responsible for variations in the impact variable in question. This paper introduces a novel probabilistic machine learning method, RMM-VAE, for identifying weather regimes targeted to a local-scale impact variable. Based on a variational autoencoder architecture, the method combines non-linear dimensionality reduction with a prediction task and probabilistic clustering in one coherent architecture. The new method is applied to identify circulation patterns over the Mediterranean region targeted to precipitation over Morocco and compared to three existing approaches: two established linear methods and another machine-learning approach. The RMM-VAE method identifies regimes that are more predictive of the target variable compared to the two linear methods, both in terms of terciles and extremes in precipitation, while also improving the reconstruction of the input space. Further, the regimes identified by the RMM-VAE method are also more robust and persistent compared to the alternative machine learning method. The results demonstrate the potential benefit of the new method for use in various climate applications such as sub-seasonal forecasting, and illustrate the trade-offs involved in targeted clustering
Evaluating the thermal impact of built environment surfaces on urban trees for achieving maximum cooling performance in the school’s car parking and walkways in the UK and Saudi Arabia
No full textDuring heatwaves built, urban areas can easily overheat, which can put people’s health at
risk or require expensive mechanical air conditioning. However, greener areas remain several
degrees colder and powerful in reducing the heat island effect and provide thermal comfort.
Urban greening proposed to be an approach to mitigating health consequences resulting from
climate change increased temperatures and heatwaves (Bowler, et al., 2010).
Built environment surfaces usually contribute to increasing local climate temperatures, and
this research would investigate the impact of built environment surfaces temperatures such
as walkways in streets and parking, on urban trees thermal performance. Before something
can be managed, it should be measured as a first step.
Urban tree thermal effect is one of the essential indicators of green infrastructure quality.
On the city scale, one of the biggest challenges of green infrastructure is how to deal with
severe heat waves by improving healthy growth and prosperity and improving the cooling
performance of urban trees. Particularly walkways and parking areas, where urban heat island
radiated. Those areas where impervious surfaces are increasing with urban expansion.
This research intends to enrich the decision-making process specifically architects, in
improving the pavement surface materials used in schools and built environments to tackle
climate change challenges in summer, particularly heat waves.
The purpose of this research is to examine the impact of built environment surfaces
temperatures on the urban tree cooling potentials and in turn, its impact on urban microclimate
in the UK and KSA hot climate.
This research examines and assesses the relationship between the surfaces of urban built
environments and the cooling potential of green spaces and trees in urban areas. A total of
18 experimental case studies have been conducted to assess the impact of heatwaves and
climate change on urban trees in both British and Saudi contexts. These studies also
examined the effects of construction materials used around trees in schools, walkways, and
car parking areas on the thermal performance of the trees. A comprehensive statistical
analysis has been conducted to assess the overall influence of construction materials on trees
in urban environments in both the UK and Saudi Arabia. The findings reveal that the impact of
construction materials temperature on urban trees is significant, and the effect in Saudi Arabia
is more substantial than it in UK. This variation could be attributed to the decrease in relative
humidity and the increase in air temperature. Consequently, climate change may result in a
similar outcome in the UK, as a result of more extensive heatwaves over the summer