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Archaeological watermarks: Settlement, landscape and seasonal flooding in historical Ireland
No full textTurloughs are karst wetland ecosystems that are virtually unique to Ireland. They are intermittently inundated on an annual basis, mainly from groundwater. This thesis concerns the interaction of past communities with the dynamic nature of these seasonal lakes from the early medieval to the early modern period in Ireland (c.400AD-1850AD).
The primary aim is to investigate human interaction with the dynamic flooding regimes of turloughs through archaeological, historical, toponymic and folklore sources, and to identify evidence for their management and manipulation by communities in Ireland. Among the aims and objectives of this research is to determine the importance of these environments as valued and significant resources over time, and their role in the cognitive landscape of past communities.
Traditional archaeological methodologies are combined with the information gained from recorded contemporary human narratives. Three main theoretical models were used in the analysis of these landscapes. These included archaeological landscape theory which views cultural landscape is a product of the interaction of humans with the physical landscape, and historical archaeology which seeks to combine traditional archaeological methodologies with the information gained from recorded contemporary historical records. Concepts of ‘Space and Place’ and lost cognitive associations are drawn from the theoretical models associated with human geography where ‘space’ refers to the abstract physical environment without a particular substantial meaning, and place refers to how human populations are aware of and interact with a defined space.
This thesis demonstrates that turloughs, and their unique physiographic features, have been used as a significant natural resource through the historical period in Ireland and have frequently served as a focal point for human activity. A key finding of this thesis is that in the case of human settlement on turlough floodplains, symbiotic settlement which accommodated the natural, already productive flooding regime was preferred, and that the natural resources available in these environments, which included fisheries and seasonal grazing pastures, were strategically exploited by communities who settled in turlough landscapes in a manner that did not disturb the natural hydrological regime. This contrasts with comparable contemporary settlement in fluctuating wetlands in Britain which engaged in large scale reclamation works, often to improve the productivity of holdings there. Other evidence shows that turlough floodplains were also exploited as suitable venues for a variety of ritual and social practices, through multiple cultural layers and contexts. The recognition of turlough floodplains as important venues for seasonal, communal, and symbolic assembly of population groups through time has been a particularly important finding of this research and identifies these landscapes as places for ritual activity as well as a resourceful and valued natural habitat
Children\u27s rights and social justice: Case studies from Nicaragua as a resource for students and teachers
No full textThe eight case studies in this volume were written as part of the “Education for Social Justice” project coordinated by Leeds Development Education Centre. This project aimed to help make development education an embedded cross-curricular theme in European education policies, and in so doing help create a climate across Europe where young people felt enthusiastic about taking action for a fairer world. The project involved schools in Slovenia, Portugal, Latvia, Estonia and Bulgaria as well as the UK.Leeds Development Education Centr
Helminth products promote anti-inflammatory trained innate immunity by imprinting long-term hematopoietic stem cells
No full textRecent research has shown that immunological memory is not confined to the cells of the adaptive immune system but can be imbued upon innate immune cells, including monocytes and macrophages, in a process known as trained innate immunity. While the exact mechanisms remain largely uncharacterized, it is thought to require epigenetic and metabolic reprogramming induced by pathogens that modify the innate immune cell to respond faster and more robustly to secondary challenge. Recently, our laboratory has demonstrated that mature macrophages can undergo anti-inflammatory trained innate immunity following in vitro and in vivo exposure to helminth-derived products. Macrophages trained with helminth products secreted more anti-inflammatory but less pro-inflammatory cytokines, which resulted in modulated T cell responses that mediated the autoimmune disease experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. However, macrophages and monocytes are often short-lived cells, and this has led to uncertainty over the longevity of trained innate immunity in mature innate immune cells found in the periphery. There is emerging evidence to suggest that hematopoietic stem cells (HSCs) in the bone marrow (BM) can be modified to produce mature innate immune cells with enhanced pro-inflammatory effector functions in a process now known as central trained innate immunity.
This study demonstrated that excretory-secretory products of the helminth Fasciola hepatica (FHES) can imprint an anti-inflammatory phenotype on long-term HSCs (LT-HSCs) and monocyte precursor populations, enhancing their proliferation and differentiation into anti-inflammatory Ly6Clow monocytes. These monocytes expand and populate multiple compartments in mice, conferring hyporesponsiveness to pro-inflammatory stimuli and reduced susceptibility to induction of EAE. Furthermore, treatment of mice with FHES enhanced myelopoiesis, and reduced inflammatory innate immune responses and suppressed migration of pathogenic Th1 and Th17 cells into the central nervous system (CNS) during EAE.
Anti-inflammatory modifications to the BM persisted for up to 8 months. Furthermore, transplantation of whole BM from mice treated with FHES transferred a bias for myelopoiesis and promoted the generation of anti-inflammatory macrophages in recipient mice that reduced susceptibility to the induction of EAE. Moreover, FACS-sorted LT-HSCs from mice treated with FHES were also capable of transplanting anti-inflammatory central trained innate immunity to recipient mice. Inhibition of epigenetic or metabolic reprogramming during FHES stimulation of BM cells blocked the development of anti-inflammatory central training in vitro.
The findings demonstrate that helminth-derived products can epigenetically and metabolically reprogram HSCs to promote development of anti-inflammatory myeloid cells in response to secondary challenge, resulting in suppressed pathogenic T cells that mediate EAE. The demonstration that helminths and their products can induce long-lasting modifications to BM-resident HSCs to produce anti-inflammatory innate immune cells sheds new light on innate immune memory and has the potential to identify novel therapeutic approaches for autoimmune diseases
T-Count optimized quantum circuit designs for single-precision floating-point division
No full textThe implementation of quantum computing processors for scientific applications includes
quantum floating points circuits for arithmetic operations. This work adopts the standard division algorithms for floating-point numbers with restoring, non-restoring, and Goldschmidt division algorithms for single-precision inputs. The design proposals are carried out while using the quantum Clifford+T gates set, and resource estimates in terms of numbers of qubits, T-count, and T-depth are provided for the proposed circuits. By improving the leading zero detector (LZD) unit structure, the proposed division circuits show a significant reduction in the T-count when compared to the existing works on floating-point division
A review of the dielectric properties of the bone for low frequency medical technologies
No full textThe dielectric properties are key parameters that quantify the interaction between electromagnetic waves and human biological tissues. In particular, the development of electromagnetic-based medical technologies rely on knowledge of the dielectric properties of bone, specifically for applications such as electrical stimulation and bone health monitoring. Electrical stimulation is used in clinics to promote the healing of bone fractures, treating non-unions, congenital pseudarthrosis, bone regeneration and during bone implant procedures. The response of the bone to any external electrical stimulation is governed by the dielectric properties of the bone, which vary with the applied frequency of the stimuli. Bone mineral density is considered a key indicator of osteoporosis diagnosis, and is assumed to be related to the dielectric properties of the bone. Therefore, dielectric properties of bones may potentially be used to diagnose osteoporosis. The bone dielectric properties can be assessed non-invasively for bone health monitoring. Several research studies have reported dielectric properties of cortical and trabecular bones in recent literature. Since dielectric properties of bone determine the response of the tissue to therapies, it is important to compile and analyze the reported dielectric data in order to have a thorough understanding of these properties. It is established from the literature that the low frequency (10 Hz-1 GHz) dielectric properties of bone are particularly important in diagnostic applications, as the correlation between the dielectric properties and bone mineral density is more significant than at higher frequencies. In this paper, the low frequency dielectric properties of the bone reported in the literature are compiled and quantitatively analysed. The results suggest that there is a significant inter- and intra- species variation in the reported dielectric data from human, bovine, porcine, and rat bone tissues. Moreover, the relationship between the dielectric properties and bone mineral density is inconsistent across the various studies, indicating that further research in this area is needed.The research leading to these results has received funding from the European
Research Council under the European Union’s Horizon 2020 Programme/ ERC Grant Agreement
BioElecPro n. 637780 and Science Foundation Ireland Grant n. 15/ERCS/3276
Impact of radial heterogeneities of biological tissues on dielectric measurements
No full textThe dielectric properties of biological tissues are relevant in dosimetry studies and in radio-frequency and microwave medical applications. Broadband tissue dielectric data is commonly acquired using open-ended coaxial probe techniques. Generally, heterogeneous tissues are accurately characterised by conducting a meticulous histological analysis of the tissue types involved in the dielectric measurement. To this extent, it is fundamental to evaluate the tissue volume interrogated by the probe, also known as the probe sensing volume or histology region. In this study, early-stage experiments are presented to investigate how radial heterogeneities can impact the histology depth. The findings of this study aim to provide the basis for more accurate dielectric characterisation of heterogeneous tissues to support microwave medical device design.The research leading to these results has received
funding from the European Research Council under
the ERC Grant Agreement BioElecPro n. 637780:
“BIOELECPRO”. This work was also supported by
the Hardiman Research Scholarship. This work has
been developed in the framework of COST Action
MiMed (TD1301)
Transitions in frailty phenotype states and components over 8 years: evidence from The Irish Longitudinal Study on Ageing
No full textAim: Fried\u27s frailty phenotype (FP) is defined by exhaustion (EX), unexplained weight loss (WL), weakness (WK), slowness (SL) and low physical activity (LA). Three or more components define the frail state, and one or two the prefrail. We described longitudinal transitions of FP states and components in The Irish Longitudinal Study on Ageing (TILDA).
Methods: We included participants aged ≥50 years with FP information at TILDA wave 1 (2010), who were followed-up over four longitudinal waves (2012, 2014, 2016, 2018). Next-wave transition probabilities were estimated with multi-state Markov models.
Results: 5683 wave 1 participants were included (2612 men and 3071 women; mean age 63.1 years). Probabilities from non-frail to prefrail, and non-frail to frail were 27% and 2%, respectively. Prefrail had a 32% probability of reversal to non-frail, and a 10% risk of progression to frail. Frail had an 18% probability of reversal to prefrail and 31% risk of death. Probabilities of transitioning from not having to having a component were: 17% for LA, 11% for SL, 9% for EX, 7% for WL and 6% for WK. Probabilities of having a FP component and dying were: 17% for WL, 15% for WK, 14% for SL, 13% for EX, and 10% for LA. Probabilities of having a component and recovering at the next wave were: 59% for WL, 58% for EX, 40% for WK, 35% for LA and 23% for SL.
Conclusions: FP states and components are characterized by dynamic longitudinal transitions. Opportunities exist for reducing the probability of adverse transitions
Understanding the global challenges to accessing appropriate wheelchairs: position paper
No full textIntroduction: Appropriate wheelchairs are often essential for the health and wellbeing of
people with mobility impairments to enhance fundamental freedoms and equal opportunity. To date, provision has mainly focused on just delivering the wheelchair instead of following an evidence-based wheelchair service delivery process. In addition, many governments have not committed to a national wheelchair provision policy. Approach: To prepare this position paper, a systemic development model, founded on the sustainable human security paradigm, was employed to explore the global challenges
to accessing appropriate wheelchairs. Positions: I: Consideration of key perspectives of wheelchair provision across the life course is essential to meet the needs to children, adults, older people and their families; II: Comprehensive wheelchair service delivery processes and a competent workforce are essential to ensure appropriate wheelchair service provision; III: Evaluations on wheelchair product quality development, performance and procurement standards are key as wheelchair product quality
is generally poor; IV: Understanding the economic landscape when providing wheelchairs is critical. Wheelchair funding systems vary across jurisdictions; V: Establishing wheelchair provision policy is a key priority, as specific policy is limited globally. Conclusion: The vision is to take positive action to develop appropriate and sustainable wheelchair service provision systems globally, for me, for you, for us
A multiscale experimentally-based finite element model to predict microstructure and damage evolution in martensitic steels
No full textThe objective of this work is to investigate the plastic deformation and associated microstructural evolution and damage in a martensitic steel at multiple length scales, using a combination of finite-element (FE) modelling and experimental measurements. A multiscale model is developed to predict damage evolution in the necked region of a uniaxial tensile test specimen. At the macroscale, a von Mises plasticity FE model in conjunction with a Gurson-Tvergaard-Needleman damage model is used to predict the global deformation and damage evolution. A physically based crystal plasticity model, incorporating a damage variable is used to investigate the microscale plastic deformation behaviour and the changes in crystal orientation under large strains. The model predicts that slip bands form at the onset of plastic deformation and rotate to become almost parallel to the loading direction at large strain. In the necked region, the initially
randomly orientated microstructure develops texture, brought about by inelastic deformation and lattice rotation towards the stable [011] orientation. The predicted crystal orientations and missorientation distribution are in good agreement with measurements obtained through electron backscatter diffraction in the centre of the necked region of the tensile test specimens. The experimental and modelling techniques developed in this work can be used to provide information on the evolution of plastic deformation and damage as well as the orientation-dependent crack initiation and microstructural evolution during large deformation of engineering materials
Quantification of the sensing radius of a coaxial probe for accurate interpretation of heterogeneous tissue dielectric data
No full textAccurate tissue dielectric measurements are crucial for the development of electromagnetic diagnostic and therapeutic devices that are designed based on estimates of the dielectric properties of diseased and healthy tissues. Although the dielectric measurement procedure is straightforward, several factors can introduce uncertainties into dielectric data. Generally, uncertainties are higher in the dielectric measurement of heterogeneous tissues, due to the fact that there is no standard procedure for acquiring and interpreting the dielectric data of heterogeneous tissues. Uncertainties related to tissue heterogeneity can be minimized by estimating the probe sensing volume, defined by the sensing depth and radius, and characterizing the tissue distribution within that volume. While several studies have investigated the sensing depth, this paper focuses on examining the sensing radius. Both dielectric measurements and numerical simulations with heterogeneous porcine tissues in the microwave range of 0.5-20 GHz have been conducted to quantify the sensing radius and the dielectric contribution of each tissue within the sensing volume. Experiments demonstrate that the sensing radius, which depends on the individual dielectric properties of the constituent tissue types, can be smaller than the probe radius. This paper further quantitatively demonstrates that the dielectric contribution of a particular tissue depends on both its location within the sensing volume and its dielectric properties. This study provides fundamental knowledge for accurately interpreting dielectric data of heterogeneous tissues, with the aim of supporting medical device development