National University of Ireland, Maynooth
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The heart of the campus: How academic libraries in Ireland are supporting student well-being
Get PDFAcademic libraries are at the heart of campus life and are therefore in a unique position to provide mental health and well-being support to students. Despite many initiatives taking place on the island of Ireland very little literature has been published providing evidence of this. Academic librarians who were either library directors, or who had responsibility for student services in the library, enthusiastically responded to a survey which asked questions regarding the provision of mental health and well-being supports in their libraries, and the drivers and barriers in doing so. The study also investigated the impact of the COVID-19 pandemic on service provision. The findings of this study and recommendations for academic libraries in Ireland will be discussed in this presentation
Impact of ischemic lesion on sleep related connectivity in the sensorimotor cortex
Get PDFIschemic events can cause cell death and tissue loss, leading to the impairment of neural circuitry by disconnection of its neural substrates. However, the highly plastic properties of the nervous system can provide recovery by boosting circuital redundancies or triggering functional adaptation/repurposing of closely related networks. In this context, understanding how ischemic brain lesions reorganize circuits directly or indirectly connected to the injury site is crucial for developing therapeutic approaches, particularly neuroprostheses based on neurostimulation for brain-rewiring. Furthermore, it is also fundamental to consider the sleep–wake cycle in such an inquiry, considering its well-established role as bearer of key mechanisms of neuroplasticity. This study aimed to investigate how an ischemic lesion in the rat’s primary motor cortex affects the connectivity of areas involved in the sensorimotor loop, specifically the premotor cortex (RFA) and the primary somatosensory cortex (S1), during sleep. We analyzed Local Field Potentials recorded during slow-wave sleep in rats with and without ischemic lesions. Functional connectivity and cross-frequency interactions were quantified using Phase Locking Value (PLV) and Phase-Amplitude Coupling (PAC) analyses, respectively. Our findings revealed a marked increase in PAC 7 days after the lesion, followed by a partial return toward baseline levels at 14 days post-lesion. These results suggest a transient reorganization of network dynamics associated with early recovery processes. The observed changes provide insights into spontaneous post-stroke plasticity during sleep and identify potential electrophysiological biomarkers of recovery. Our findings may contribute to the design of sleep-integrated neurostimulation strategies to promote motor rehabilitation after stroke
Editorial: A Fond Farewell to the Irish Journal of Management
Get PDFThe abstract is included in the text
Characterisation of host adaptation processes in the fungal pathogen Aspergillus fumigatus
Get PDFAspergillus fumigatus represents an ever-present threat for vulnerable individuals as fungal conidia are ubiquitous and are inhaled daily. Infection occurs when optimal conditions are present resulting in a range of disease states, primarily in the context of preexisting lung damage and immunosuppression. Despite the threat this species imposes it appears to be an accidental pathogen as its primary niche is as a saprophyte in decaying plant matter. Survival in the soil has shaped A. fumigatus traits that facilitate survival in human host. This existence also equipped A. fumigatus with an array of effectors that have cross-reactivity through targeting of conserved mechanisms which can be repurposed to survive in the human body. The human lung is a terminal host for fungal development and dissemination and as such the fungus can only aim to survive but not disseminate. The lung represents a hostile environment consisting of challenges from the innate immune response, nutrient limitation and competition with microorganisms competing for the same limited resources. The rates of A. fumigatus infections are increasing globally, compounded by climate change and the rise in drug resistant strain. Despite the growing burden of disease, the mechanisms governing host adaptation and persistence remain poorly elucidated. To examine the host adaptation processes occurring in the lung, phenotypic and proteomic analysis of
A. fumigatus growth in response to isolated aspects of this environment was performed.
Examination of A. fumigatus development using Galleria mellonella as an innate immune system analogue, patterns regarding fungal metabolic preferences and virulence factor production have been further characterised. Prolonged subculture of
A. fumigatus within an agar system containing components of the immune response and the nutritional profile of G. mellonella identified reduced virulence and increased tolerance to oxidative stress and antifungal agents. These changes were governed by minor alteration to the fungal proteome, suggesting the requirements for survival as an environmental saprobe to persistence in a human host may not be a difficult transition. Examination of released fungal proteins in vivo in G. mellonella demonstrated an initial preference for carbon metabolism and an emphasis on amino acid metabolism in later stages of infection which may fuel the production of fungal secondary metabolites. Similar trends were observed in the ex-vivo pig lung (EVPL) model, an analogue of host lung tissue, where A. fumigatus induced immune activation and fibrosis within the tissue. Similar metabolic patterns and secondary metabolites were detected during colonisation in this model. Characterisation of fungal growth in response to bacterial lung pathogens identified secreted product of Klebsiella pneumoniae could induce secondary metabolite production including gliotoxin and inhibited fungal growth. Physical interaction with P. aeruginosa also demonstrated inhibited fungal development in the EVPL model. These studies provide key insight into the initial interaction of the fungus to its host and highlights key metabolic and fungal developmental factors integral to successful colonisation. These insights can be utilised in the development of next generation, more effective and specific antifungal agents to treat this deadly disease
Nonlinear model predictive control strategies for a cyclorotor wave energy device
Get PDFWave energy is one of the untapped renewable
energy sources, requiring further development of wave energy
converters (WECs) to become competitive with wind and solar
energy. A significant challenge for WEC development is the
high levelized cost of energy (LCoE) associated with traditional
heaving or diffraction-based devices. However, analytical and
experimental evaluation of lift-based cyclorotor WECs indicate
that these devices can achieve superior power absorption
when optimised using advanced control techniques, potentially
increasing power production by several times, compared to
uncontrolled scenarios. This work presents the first implementation of Nonlinear Model Predictive Control (NMPC) for a
cyclorotor WEC. The control strategy relies on the separation
principle, assuming accurate wave prediction over the control
horizon for panchromatic waves. A comparison of various pitch
and/or velocity control strategies is conducted for different
irregular sea states. The results, obtained by simulations,
confirm and exceed the capability, previously predicted by the
theoretical optimal control solution, of a cyclorotor WEC to
absorb up to 70% of wave energy
Palmitate enhances MSC immunomodulation of human macrophages via the ceramide/CCL2 axis in vitro
Get PDFAbstract Background
The immunomodulatory function of human mesenchymal stromal cells (MSCs) strongly depends on external factors; such as cytokines and other signalling molecules encountered in the disease microenvironment. An insufficiently inflammatory environment can fail to activate MSCs, and certain signals can impair their function. Obesity is on the rise worldwide, making it an additional factor to be considered prior to MSC therapy, as the microenvironment presents its own challenges. Elevated levels of serum free fatty acids, specifically palmitate, have the potential to affect MSC therapy. Palmitate-exposure has been shown to impair MSC immunomodulation of T cells in vitro. However, this is yet to be studied in the context of macrophages.
Methods
MSCs from three independent donors were exposed to 0.4mM of palmitate for 6–24 h. Gene expression, protein production and functional capacity were then assessed in response to palmitate. A ceramide synthesis inhibitor (Fumonisin B1) and a CC-chemokine ligand 2 (CCL2)-neutralising antibody were further used to assess the impact of these components on palmitate-associated immunomodulation.
Results
We demonstrated that palmitate-exposed MSCs have enhanced suppression of human monocyte-derived macrophage (MDM) production of tumour necrosis factor α (TNFα), in a CCL2-dependent manner. We further elucidated parts of the pathway, such as ceramide synthesis, through which palmitate promotes this enhanced immunomodulation of macrophages.
Conclusion
Palmitate-exposed MSCs show enhanced immunomodulation of human MDMs, through the ceramide/CCL2 axis in vitro
Dysfunctional Fear? Explaining (Mis)alignment among the Emotive and Cognitive Dimensions of Reactions to Victimization Threat
Get PDFVictimization threat appraisals contain both cognitive and emotive components. Ideally, for precautionary choices, both components support one another; however, an imbalance has been a persistent concern in the fear of victimization literature, but there is little theory to account for why. We explore a theory that might account for (1) the sources of variation in the extent of threat reactions and (2) imbalances between cognitive perceptions of risk and emotional worry. Our method employs an item response theory (IRT) approach to measurement in a multilevel regression framework using a national sample of 1,500 adults from the United States. Results show significant evidence of variation in the balance of cognition and emotion in threat reactions, and these imbalances are predictable
CAPM and Skewness Pricing Under Probability Weighting: Based on the Generalised Wang Transform
Get PDFIn this paper, we examine the conditions under which the capital asset pricing model (CAPM) holds with heterogeneous probability weighting. Using the generalised Wang transform within rank‐dependent expected utility, we show that CAPM holds for heterogeneous risk‐averse investors, while the security market line theorem (SMLT) applies to heterogeneous loss‐averse investors. However, CAPM under loss aversion requires homogeneous investors. Revisiting skewness pricing, we find that probability weighting, rather than the S‐shaped value function, drives skewness overpricing. The preference for skewed assets stems from the high distorted mean under probability weighting
Advancing the Use of Service Statistics for Estimating Modern Contraceptive Use through Bayesian Modelling Approaches
Get PDFMonitoring family planning progress requires accurate and timely estimates of key
indicators such as the modern contraceptive prevalence rate (mCPR), defined as
the proportion of women of reproductive age using modern contraceptive methods.
However, large-scale survey data, often the primary source of these mCPR estimates,
are infrequently collected, leading to data gaps. Family planning service statistics,
routinely collected during service delivery, provide a supplementary data source.
From these statistics, an indicator known as Estimated Modern Use (EMU) can be
derived, but it is a biased estimator of mCPR and has uncertainties that need to
be considered. This thesis focuses on advancing the methodology, application, and
usability of EMU by quantifying and accounting for biases and uncertainties and
ultimately better supporting low- and middle-income countries in tracking family
planning progress.
First, we refine the derivation of EMU by improving upon necessary adjustments for
missing private sector contributions to family planning service statistics databases.
Previous methods carried out adjustments assuming constant contraceptive supply
share distributions over time and without quantifying uncertainty associated with
supply share estimates. We update and improve upon the EMU calculation to
reflect time-varying contraceptive supply and capture uncertainty in the private
sector adjustment, resulting in observation-specific uncertainty previously unseen
in EMU derivation. These improvements are demonstrated through country-level
case studies.
Next, we develop a new approach to incorporating EMUs into the Family Planning
Estimation Tool (FPET), which generates estimates and short-term projections
of mCPR. We use a Bayesian hierarchical modelling approach to estimate data
type-specific EMU uncertainty and across country variance parameters before
incorporating the resulting estimates into FPET. We introduce a Bayesian hierarchical
model when using EMUs in FPET to capture uncertainty, accounting
for country- and type-specific uncertainties through the hierarchically estimated
variance hyperparameters. Model validation results and anonymised country-level
case studies highlight the impact to mCPR estimates when including EMU data in
FPET using this approach. Validation findings demonstrate improved predictive
performance with EMU inclusion compared to relying on survey data alone, while
case studies provide further insights into its effects across different country contexts.
Finally, we present a paper to describe the details and implementation of ss2emu,
an open-source R package, developed to perform the most advanced SS-to-EMU
calculation process in R. This tool complements existing workflows performed by
country-level data experts, providing reproducible datasets and visualisations for
use in FPET. By offering a scalable and user-friendly solution, the tool enhances
accessibility and empowers users, such as family planning monitoring and evaluation
officers, to make more informed decisions in family planning monitoring.
Together, these contributions improve the accuracy, integration, and usability of
EMU as a family planning indicator, enabling countries to better monitor progress
toward family planning goals and address data gaps with confidence