21684 research outputs found
Sort by
Impact of exercise combined with consumption of caloric-restricted meals/diets with different carbohydrate and fat content on body weight and gastrointestinal appetite hormones, subjective appetite in adults with overweight and obesity
No full textNo abstract available
Synthesis and application of Mo₆S₈₋ₓSeₓ (x = 0 - 8) solids in zinc ion batteries
No full textAbstract not currently available
Conceptualising corporate philanthropy and measuring its effects on employee-based brand equity
Get PDFThis thesis explores the evolving role of corporate philanthropy (CP) in forming and developing employee-based brand equity (EBBE), set against the backdrop of increasing global disruptions and the growth of philanthropic contributions. There is a need to refine the understanding and clarify the conceptual ambiguities of CP nowadays, particularly its impact on business management and societal engagement. Additionally, the potential of linking corporate philanthropic activities with the perspectives of internal stakeholders has been insufficiently recognised.
Addressing these gaps, this research aims to redefine CP within a business context, distinguishing it from general philanthropic efforts and similar concepts such as Corporate Social Responsibility (CSR). Focusing on the ‘unintentional reciprocal’ nature of CP, where benefits flow between the corporation and society, this study particularly examines how philanthropic involvement in the workplace influences the development of employeebased brand equity. It seeks to understand CP’s role not just as an altruistic practice but as a capable tool of enhancing corporate brand strength through employees’ active roles.
The research employs a mixed-methods approach with a sequential exploratory design. It begins with semi-structured interviews to get insights about employees’ perceptions, feelings, and actions towards CP and their corporate brands by thematic analysis, followed by an online survey with a representative UK employee sample to empirically test the proposed EBBE model. Supported by Fuzzy-set Qualitative Comparative (fsQCA) Analysis, it enables a nuanced examination of the complex dynamics between CP and EBBE.
Building on Keller’s Brand Equity Model, this thesis contributes to the theoretical landscape by offering a refined understanding of CP’s integration within corporate branding and how this drives brand equity from an employee-centric perspective and a new focus on taking employee-based brand equity as a process with complex nature. The practical implications of this research are that it provides a diagnostic tool for practitioners to enhance their internal branding practices and strengthen employee-based brand equity effectively through CP initiatives. This research bridges theoretical gaps and enhances practical understanding, paving the way for more informed brand management and philanthropic involvement
Chiralization of star-products and the isomorphisms of deformations and quantizations of Kleinian singularities
Get PDFThis thesis contains two directions of research, both related to the quantizations and deformations of Poisson structures.
In the first part, we study the chiralization of star-products, a problem related to the quantization of Poisson vertex algebras. For a Poisson algebra A, a star product is a new product ⋆ such that the associative algebra A = (A, ⋆) is a quantization of A. Famous examples are the Moyal-Weyl and Gutt star-products. Poisson vertex algebras are the chiralization of Poisson algebras and their quantizations are vertex algebras, which are the chiralization of associative algebras. A star-deformation of a Poisson vertex algebra V is a vertex algebra structure Y⋆ such that the vertex algebra V = (V, Y⋆) is a quantization of V. Star-deformations can thus be seen as the chiral analogue of a star-product, although they are not compatible with the Zhu functors. To solve this, we introduce and study the algebraic structure of ℏ-deformed vertex algebras, which is closely related to the Zhu functor. A chiral star-product is then defined as a deformation of a Poisson vertex algebra into an ℏ-vertex algebra. We show that chiral star-products commute with the Zhu functor, giving back a star-product on the corresponding Poisson algebra. By putting ℏ = 0, we obtain a star-deformation. We study the problem of constructing chiral star-products and we provide explicit formulae in some important examples, including when V is a free-field vertex algebra, the affine vertex algebra, or the Virasoro vertex algebra. In particular, these formulae give the chiralization of the Moyal-Weyl and Gutt star-products. Additionally, we provide a new, more natural proof of the associativity of the Zhu algebra using the formalism of ℏ-vertex algebras.
In the second part, we deal with the algebra of functions on Kleinian singularities. It is known that, in this case, the parameter space of filtered Poisson deformations and the parameter space of non-commutative quantizations coincide. We consider all possible isomorphisms between the various deformations (as Poisson algebras) and all isomorphisms between the quantizations (as associative algebras); these form two groupoids, which we denote PIso and Iso. We prove that, for a Kleinian singularity of type A or D, the groupoids Iso and PIso are isomorphic. In particular, the group of automorphisms of the deformation and the quantization corresponding to the same deformation parameter are isomorphic. Furthermore, we describe the groups of automorphisms as abstract groups: for type A they have an amalgamated free product structure, for type D they are subgroups of the group of Dynkin diagram automorphisms. For type D we additionally compute all the possible isomorphisms between deformations as affine varieties
Applications of process analytical tools in digital chemistry
No full textAbstract not currently available
Peer support workers’ experiences of wellbeing and their role in the implementation of advance statements: a systematic review and grounded theory study
Get PDFAbstract available at each chapter
Can anthropogenic biodiversity and geodiversity associated with legacy industrial waste help offset decreasing global biodiversity?
Get PDFAnthropogenic substrates, including materials such as steel slag, paper mill sludge, oil shale spoil and colliery spoil, were frequently dumped and are still dumped today in many countries where such waste is produced. In some countries, dumping of such materials is restricted due to increased health and safety regulations and due to improved waste recycling streams. Such substrates have become byproducts and are used in various products and/or applications. Legacy dumps, those that have been around for many years, can theoretically be excavated for such useful byproducts, but this can be costly and time-consuming. Additionally, many legacy anthropogenic substrate sites have biodiverse and/or rare wildlife communities, as the characteristics of the substrate can support favourable or acceptable conditions for many species. Plant species that might easily be outcompeted on high-nutrient soils may benefit from reduced competition on lower-nutrient anthropogenic substrate, for example. Invertebrates on such sites can benefit from habitat mosaics, bare patches and varied topography, for example. Anthropogenic substrate sites can be grouped as a type of brownfield site, those that are associated with former industry and anthropogenic activities. Some biodiverse brownfield sites are recognised in legislation in multiple countries, for example, Open Mosaic Habitat on Previously Developed Land, or Calaminarian Grasslands. However, assessment and protection of wildlife on these sites is often lacking and they are often preferentially chosen for development by councils, governments, developers and so on. The very features of these sites which can be so advantageous to certain species are therefore vulnerable to being removed, covered or otherwise modified by people in the name of restoration, remediation or development, for example. In order to better understand the features of these sites that can be utilised by wildlife, it is important to recognise how the substrate heterogeneity and geodiversity of many anthropogenic substrates might influence or be associated with specific species, especially plants. This study addresses questions concerning the biodiversity and substrate associations of multiple plant species and communities of anthropogenic substrate sites. Substrate geochemistry and mineralogy was determined across a suite of case study sites with different types of anthropogenic substrate, in combination with plant surveys of the sites. Analyses were carried out to look for statistically significant associations between different substrate variables and the plant species and/or communities recorded on the sites. Upon examination of the biodiversity levels and substrate associations of open plant communities and species on six case study sites, high biodiversity levels and/or rare and uncommon species were recorded in multiple plant communities across all six sites. It was found that the geochemistry on capped and uncapped areas of a partially remediated slag bank, while statistically significantly different, supported biodiversity levels which were not statistically significantly different, demonstrating that both remediated and unremediated parts of the slag bank contributed to the site’s biodiversity. The sampling and analyses of overall geochemistry and plant communities and species present on two sites predominantly covered in blast furnace slag demonstrated multiple associations between decreased or elevated concentrations of certain elements and the presence of certain plant communities and species. Overall, many anthropogenic substrate sites can support high levels of biodiversity, but these can vary between substrate types. It was seen that in plant communities with lower biodiversity levels, there could be at least one rare or uncommon species present, so this study demonstrated that low biodiversity does not necessarily indicate the entire ecological value of the community. Additionally, biodiversity can be influenced by multiple factors, some of which were outside of the scope of this study due to time and sampling constraints. This study emphasises the need to assess anthropogenic substrate sites on a caseby-case basis, rather than treating them all with the same or similar management styles
Machine learning-based wind turbine control systems for demand-oriented scenarios
Get PDFWhen wind power has an increasing share towards a 100% renewable society, wind energy conversion systems (WECSs) need to consider a requirement of the grid generation-consumption equilibrium, i.e., wind turbines (WTs) should be able to adjust their output according to power demand. However, current WTs focus on maximum power capture, which has intrinsic disadvantages in power scheduling. Hence, this study aims for machine learning (ML) based control systems that realize flexible wind capture in demand-oriented scenarios.
First, this study reviews various turbine components and establishes corresponding control models. Second, aerodynamic modelling relies on an artificial neural network (ANN) to predict thrust, torque, and power from the turbine state. Subsequently, a novel online power strategy (OPS) based on an aerodynamic model solves the 2-degree-of-freedom (DOF) optimization of the rotor speed control (RSC) and pitch angle control (PAC), which has two implementations: power reference point tracking (PRPT) and reinforcement learning (RL). Besides, the OPS has a local linearization to estimate thrust and torque sensitivities for optimal control configuration. When a wind processing unit updates wind velocity and direction signals, the OPS receives the velocity signal to calculate the 2-DOF solution and unwraps the direction signal as the command of the yaw angle control (YAC), which achieves a complete 3-DOF regulation of rotation, pitch, and yaw. Besides, the OPS framework has four control implementations: one model-free controller and three model-based controllers. In addition, our turbine control system can integrate wind forecasting to enhance the capability of handling wind stochastics.
The case study verifies and proves the accuracy and reliability of the OPS-based control framework in four simulation cases. The proposed turbine control can track different power targets and ensure reliable output in stochastic winds. Therefore, this control framework can contribute to intelligent WTs for large-scale grid integration
Investigating Asymmetric dimethylarginine (ADMA) and Calcium-sensing receptor (CaSR) signalling in the macrophage
Get PDFMacrophages play a significant role in maintaining physiological homeostasis and orchestrating immune responses. In vascular diseases like atherosclerosis, they actively participate in plaque formation and progression by accumulating lipids and modulating inflammatory processes. A G-protein coupled receptor (GPCR) known as the calcium-sensing receptor (CaSR) is activated by a plethora of ligands and couples to distinct signalling cascades. Initially recognised for its role in regulating calcium (Ca2+) levels in calciotropic tissues, the CaSR has since been revealed to exhibit tissue/cell-specific effects. In macrophages, CaSR expression is confirmed where it influences immunological processes. Our research group demonstrated that asymmetric dimethylarginine (ADMA), an endogenous nitric oxide synthase (NOS) inhibitor, acts as a CaSR ligand in adipocytes, exerting NOS-independent effects. Based on this, it was hypothesised that a similar signalling pathway operates in macrophages, modulating inflammation and can be targeted in disease.
In this study, immunocytochemistry confirmed the expression of both CaSR and the ADMA-metabolising enzyme, dimethylarginine dimethylaminohydrolase-2 (DDAH-2), in the RAW264.7 macrophage cell line used in this investigation, indicating their functional presence within these cells. Furthermore, their mRNA expression was unaffected by the pro-inflammatory stimuli, lipopolysaccharides (LPS). Next, the immunological impact of the DDAH-2/ADMA metabolic pathway in inflammation was explored using RNA-sequencing of LPS-stimulated murine macrophages with a macrophage-specific DDAH-2 knockout. This revealed that DDAH-2 plays a crucial role in modulating several genes associated with the LPS-response, exerting an anti-inflammatory effect. Specifically, DDAH-2 attenuates LPS-stimulated effects in macrophages, including antigen presentation, phagocytosis and chemotaxis. Additionally, DDAH-2 was found to influence the expression of a number of CaSR target genes that were previously identified in the literature.
Furthermore, qPCR investigations on the role of ADMA in the expression of selected genes that displayed differential expression upon DDAH-2 deletion showed that ADMA regulates Il17a expression, highlighting a pro-inflammatory effect of ADMA in these cells. This study further revealed that ADMA does not influence the expression of any of the other selected genes for validation, including those recognsised as CaSR targets. This demonstrates that DDAH-2 has ADMA-independent effects in activated macrophages. This thesis also delved into the impact of CaSR on macrophage function, revealing its pro-inflammatory role. Specifically, in non-stimulated macrophages, activation of CaSR by its positive allosteric modulator (PAM), cinacalcet, induced IL-6 expression. ADMA treatment in these cells did not elicit a similar response, indicating the absence of ADMA-CaSR crosstalk in IL-6 regulation. This study further demonstrated the pro-inflammatory effect of ADMA in non-stimulated macrophages where ADMA induced a dose-dependent induction of IL-1β and TNF-α which was independent of CaSR signalling.
By developing a novel macrophage-specific CaSR knockout mouse model, this thesis validated the utility of this model for future investigations into macrophage CaSR. This validation was achieved through confirmed significant deletion of CaSR and the viability of these mice. Furthermore, this work demonstrated that macrophage CaSR deficiency resulted in the upregulation of TNF-α in non-stimulated macrophages, highlighting CaSR’s role in regulating both pro- and anti- inflammatory effects in macrophages. Additionally, the absence of the CaSR in macrophages resulted in an age- and sex-dependent reduction in weight gain observed in female mice, an observation that requires exploration in future studies.
Taken together, this thesis demonstrates DDAH-2, ADMA, and CaSR as regulators of the macrophage response. Nevertheless, it did not reveal a signalling crosstalk between ADMA and CaSR within this cell type. Future research should focus on elucidating the mechanisms underlying the observed effects, where they can be explored as potential drug targets against pathologies where macrophages are implicated
Data sources:
Access Repository Dashboard
Do you manage Open Research Online? Become a CORE Member to access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard! 👇