NUI Maynooth Eprint Archive
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Franck-Condon Calculations of the Absorption and Emission Spectra of Aromatic Molecules – Phthalocyanines and Squarates
No full textQ-state absorption spectra of the phthalocyanines (Pc) H2Pc, MgPc, ZnPc and AlPcCl
have been simulated by calculating Franck-Condon (FC) factors with time-dependent
density functional theory (TD-DFT) using M11, PBE0 and B3LYP functionals and the 6-
31G(d) basis set. Comparisons of the electronic band origins (�0,0) recorded under low
temperature, jet-cooled conditions with the predicted (T = 0 K) values, indicate that the
B3LYP functional provides the best results for the three metal phthalocyanines (MPc).
For H2Pc the M11 functional performed marginally better than B3LYP. The FC spectrum
simulated for AlPcCl at 60 K accounts very well for strong hot bands present in the
recorded excitation spectrum. The vibrational motion responsible was identified as a low
frequency out-of-plane bending mode at 17.77 cm-1
activated when the GS C4v symmetry
is reduced to C2v in the ES. The long-range FC vibronic structure was compared with He
droplet data which provides the simplest spectra enabling the direct vibronic mode
assignments. The assigned band structures present in excitation are also present in
emission - a finding consistent with the similarities in the geometries calculated for the
phthalocyanines in the ground and excited Q-state. TDDFT was used to calculate vertical
excitation energies of squarate dianion (C4O4
2-
) revealing a previously undocumented
� → �
∗
transition occurring at 25066.43 cm-1
in vacuum. This lowest energy allowed
transition was investigated by optimising the ground state geometry and calculating its
absorption in a variety of solvents with a range of dielectric constants using the
Polarisable Continuum Model (PCM). It was found that the � → �
∗
transition is highly
solvent dependent due to a large charge separation in the associated molecular orbitals.
The transition blueshifts strongly with the increase in dielectric constant so that in water
it is located in the UV region (44477 cm-1
A new multiplex SARS-CoV-2 antigen microarray showed correlation of IgG, IgA, and IgM antibodies from patients with COVID-19 disease severity and maintenance of relative IgA and IgM antigen binding over time
No full textZoonotic spillover of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to humans in December 2019 caused the coronavirus disease 2019 (COVID-19) pandemic. Serological monitoring is critical for detailed understanding of individual immune responses to infection and protection to guide clinical therapeutic and vaccine strategies. We developed a high throughput multiplexed SARS-CoV-2 antigen microarray incorporating spike (S) and nucleocapsid protein (NP) and fragments expressed in various hosts which allowed simultaneous assessment of serum IgG, IgA, and IgM responses. Antigen glycosylation influenced antibody binding, with S glycosylation generally increasing and NP glycosylation decreasing binding. Purified antibody isotypes demonstrated a binding pattern and intensity different from the same isotype in whole serum, probably due to competition from the other isotypes present. Using purified antibody isotypes from naïve Irish COVID-19 patients, we correlated antibody isotype binding to different panels of antigens with disease severity, with binding to the S region S1 expressed in insect cells (S1 Sf21) significant for IgG, IgA, and IgM. Assessing longitudinal response for constant concentrations of purified antibody isotypes for a patient subset demonstrated that the relative proportion of antigen-specific IgGs decreased over time for severe disease, but the relative proportion of antigen-specific IgA binding remained at the same magnitude at 5 and 9 months post-first symptom onset. Further, the relative proportion of IgM binding decreased for S antigens but remained the same for NP antigens. This may support antigen-specific serum IgA and IgM playing a role in maintaining longer-term protection, important for developing and assessing vaccine strategies. Overall, these data demonstrate the multiplexed platform as a sensitive and useful platform for expanded humoral immunity studies, allowing detailed elucidation of antibody isotypes response against multiple antigens. This approach will be useful for monoclonal antibody therapeutic studies and screening of donor polyclonal antibodies for patient infusions
Spring Regional Sea Surface Temperatures as a Precursor of European Summer Heatwaves
No full textDifferent spring and early summer North Atlantic sea surface temperature anomalies (SSTAs)
have been shown to precede recent European summer heatwaves (EuSHWs). So far, the limited number of
observed events associated with several physical mechanisms has prevented a robust identification of SSTAs as
precursors. Here, we extend beyond previous studies by combining 100 historical simulations (1850–2005) of
the MPI Grand-Ensemble with an explainable neural-network method. We find that the spring tripolar North
Atlantic pattern with positive SSTAs in the Subtropical Gyre is a precursor of EuSHWs. In addition, positive
SSTAs west of the Iberian Peninsula, and in the North Sea, the Baltic Sea and the Mediterranean Sea relate to
distinct early summer soil moisture anomaly patterns and are precursors of western and southeastern EuSHWs,
respectively. While the phase of the tripolar North Atlantic pattern indicates whether a EuSHW might emerge,
regional SSTAs indicate the spatial characteristics of EuSHWs
Incremental adaptation when transformation fails: The importance of place-based values and trust in governance in avoiding maladaptation
No full textClimate change threatens human wellbeing and adaptation is essential. To-date, little research has examined connections between incremental and transformative adaptation. We address this gap using two multi-functional flood defence projects in Clontarf, a community in Dublin, Ireland, one of which represents transformative and the other incremental adaptation. Using a repeated study, we ask (i) does the importance of place-related values differ depending on whether adaptation is incremental or transformative, and (ii) what role does trust in governance play in incremental adaptation when transformation fails? Surveys were administered in Clontarf in 2014 (n = 280) after community resistance to transformative flood defences. A follow-up study using an identical survey was undertaken to evaluate separate incremental flood defences in 2016 (n = 242). Results highlight several important findings. First, both adaptation interventions show repeated potential threats to place from perceived weak governance rather than from disruptive place change caused by climate change. Second, where place attachment is strong, communities may repeatedly resist potential threats to place by challenging poor governance. However, this inadvertently threatens place disruption from climate change e.g., extreme climatic events. This could cause maladaptation, tying future decisions to past actions and failing to consider alternative transformative adaptation pathways. Finally, community discussions on transformative pathways and avoiding maladaptation risks are crucial for successful adaptation. This includes recognising trade-offs between place disruption threats from proposed adaptation strategies and climate change. Governance processes may subsequently need to transform and incorporate learnings or risk repeated resistance to adaptation previously considered rational. Many of these issues are likely to be encountered in all regions globally and across multiple adaptation sectors. Findings therefore provide important evidence to improve adaptation outcomes more generally
Reassessing long-standing meteorological records: an example using the national hottest day in Ireland
No full textThis analysis highlights the potential value in reanalysing early national meteorological records from around the world. These were oftentimes measured via techniques that preceded standardisation of instrumentation and methods of observation and thus could be subject to considerable biases and uncertainties. This analysis uses the techniques pioneered by WMO record assessment teams. The highest currently recognised air temperature (33.3 ∘C) ever recorded in the Republic of Ireland was logged at Kilkenny Castle in 1887. The original observational record however no longer exists. Given that Ireland is now the only country in Europe to have a national heat record that was set in the 19th century, a reassessment of the verity of this record is both timely and valuable. The present analysis undertakes a fundamental reassessment of the plausibility of the 1887 temperature record using methods similar to those used to assess various weather extremes under WMO auspices over recent years. Specifically, we undertake an inter-station reassessment using sparse available records and make recourse to the new and improved 20CRv3 sparse-input reanalysis product. Neither surrounding available stations nor the reanalysis offer substantive support for the Kilkenny record of 33.3 ∘C being correct. Moreover, recent data rescue efforts have uncovered several earlier extreme values, one of which exceeds the Kilkenny value (33.5 ∘C on 16 July 1876 recorded at the Phoenix Park). However, the sparsity of early observational networks, a distinct lack of synoptic support from 20CRv3 for many of the extreme heat values, and the fact that these measurements were obtained using non-standard exposures lead us to conclude that there is grossly insufficient evidence to support any of these 19th century extremes as robust national heat record candidates. Data from the early 20th century onwards benefit from a denser network of stations undertaking measurements in a more standardised manner, many under the direct auspices of Met Éireann and its predecessors, adhering to WMO guidance and protocols. This enables more robust cross-checking of records. We argue that the Met Éireann-recognised 20th century heat record from Boora in 1976 is verified as the most plausible robust national temperature record based upon the synoptic situation and comparisons with nearby neighbouring stations. This measurement of 32.5 ∘C thus likely constitutes the highest reliably recorded temperature measurement in the Republic of Ireland. Ultimately, the formal decision on any reassessment and reassignment of the national record rests with the national meteorological service, Met Éireann
Current Topics in Technology-Enabled Stroke Rehabilitation and Reintegration: A Scoping Review and Content Analysis
No full textBackground. There is a worldwide health crisis stemming from the rising incidence of various debilitating chronic diseases, with stroke as a leading contributor.
Chronic stroke management encompasses rehabilitation
and reintegration, and can require decades of personalized medicine and care. Information technology (IT) tools
have the potential to support individuals managing chronic
stroke symptoms. Objectives. This scoping review identifies prevalent topics and concepts in research literature
on IT technology for stroke rehabilitation and reintegration,
utilizing content analysis, based on topic modelling techniques from natural language processing to identify gaps
in this literature. Eligibility Criteria. Our methodological
search initially identified over 14,000 publications of the last
two decades in the Web of Science and Scopus databases,
which we filter, using keywords and a qualitative review, to a
core corpus of 1062 documents. Results. We generate a 3-
topic, 4-topic and 5-topic model and interpret the resulting
topics as four distinct thematics in the literature, which
we label as Robotics, Software, Functional and Cognitive.
We analyze the prevalence and distinctiveness of each thematic and identify some areas relatively neglected by the
field. These are mainly in the Cognitive thematic, especially
for systems and devices for sensory loss rehabilitation,
tasks of daily living performance and social participation.
Conclusion. The results indicate that IT-enabled stroke literature has focused on Functional outcomes and Robotic
technologies, with lesser emphasis on Cognitive outcomes
and combined interventions. We hope this review broadens
awareness, usage and mainstream acceptance of novel
technologies in rehabilitation and reintegration among clinicians, carers and patients
Using formal methods for autonomous systems: Five recipes for formal verification
No full textFormal Methods are mathematically-based techniques for software design and engineering, which enable the unambiguous description of and reasoning about a system’s behaviour. Autonomous systems use software to make decisions without human control, are often embedded in a robotic system, are often safety-critical, and are increasingly being introduced into everyday settings. Autonomous systems need robust development and verification methods, but formal methods practitioners are often asked: Why use Formal Methods for Autonomous Systems? To answer this question, this position paper describes five recipes for formally verifying aspects of an autonomous system, collected from the literature. The recipes are examples of how Formal Methods can be an effective tool for the development and verification of autonomous systems. During design, they enable unambiguous description of requirements; in development, formal specifications can be verified against requirements; software components may be synthesised from verified specifications; and behaviour can be monitored at runtime and compared to its original specification. Modern Formal Methods often include highly automated tool support, which enables exhaustive checking of a system’s state space. This paper argues that Formal Methods are a powerful tool for the repertoire of development techniques for safe autonomous systems, alongside other robust software engineering techniques
Laser-Powered UAVs for Wireless Communication Coverage: A Large-Scale Deployment Strategy
No full textThe use of unmanned aerial vehicles (UAVs) is strongly advocated for sixth-generation (6G) networks, as the 6G standard will not be limited to improving broadband services, but will also target the extension of the geographical cellular coverage. In this context, the deployment of UAVs is considered a key solution for seamless connectivity and reliable coverage. That being said, it is important to underline that although UAVs are characterized by their high mobility and their ability to establish line-of-sight (LOS) links, their use is still impeded by several factors such as weather conditions, their limited computing power, and, most importantly, their limited energy. In this work, we are aiming for the novel technology that enables indefinite wireless power transfer for UAVs using laser beams. We propose a novel UAV deployment strategy, based on which we analyze the overall performance of the system in terms of wireless coverage. To this end, we use tractable tools from stochastic geometry to model the complex communication system. We analyze the user’s connectivity profile under different laser charging capabilities and in different type of environments. We show a decrease in the coverage probability by more than 12% in moderate-to-strong turbulence conditions compared to low turbulence conditions. We also show how the connection rate to the aerial network significantly decreases in favor of the terrestrial network for short laser charging ranges. We conclude that laser-powered drones are considered interesting alternatives when placed in LOS with users, in low-to-moderate optical turbulence, and at reasonable ranges from the charging stations
Whose lips are sealed? Gender differences in knowledge hiding at work
No full textKnowledge hiding – intentionally concealing knowledge from a colleague who requested it – is often damaging for individuals and organizations. Amongst the factors explaining knowledge hiding, one has been overlooked, despite being an important lens for understanding employee behaviours: gender. In this article, we investigate its relevance by examining whether and how gender shapes two complementary aspects of knowledge hiding behaviour: frequency of hiding, and the approaches that knowledge hiders employ to do so. Building on extant literature about gender roles at the workplace, we suggest that the social roles into which women and men are socialized, and the sanctions they face if they behave incongruently with these roles affect both aspects of knowledge hiding. We explore these ideas in a multi-wave study of full-time employees based in the United Kingdom (n = 449). Our findings suggest that men hide their knowledge from colleagues more frequently. In addition, both women and men hide knowledge in a way that is congruent with the expectations of others regarding their social role: that is, women use evasive hiding and playing dumb more than men, while men use rationalized hiding more than women. A male-dominated context reduces these differences between genders
First-generation Migrant Student Experiences in Higher Education Spaces in Ireland
No full textFirst-generation students are a growing cohort in higher education (HE) and research around this group of learners is a developing area in Ireland and internationally. This qualitative study explored the accounts by ten first-generation students who self-selected and who are the first in their families to attend higher education in Ireland, of their experiences while enrolled in a higher education institute in Ireland. One-to-one in-depth interviews were conducted using semi-structured questions in order to bring to light how they accessed higher education in Ireland, the difficulties they encountered, their motivations, and the strategies that helped them to successfully participate in higher education.
The research presented here is guided by Bourdieu’s (1986) theoretical framework and his concepts of habitus, field, and capital, together with Yosso’s (2005) theory of Community Cultural Wealth (CCW), in particular her ideas around familial capital, along with drawing on the lens of Critical Race Theory (CRT) through which the experiential knowledge shared by the participants in the study is explored. The significance of the role of CCW is offered here as a form of resistant capital that may promote first-generation students’ access to and continued study in HE. In doing so, I suggest that a ‘personal capital of persistence’ is developed.
The findings are centred on four key areas: the long journeys into higher education, the importance of family relationships; pressures; and student engagement with learning. Findings show that cultural capital is supported by positive values around education in the domestic habitus and related familial and peer support networks. The students in this study showed evidence of acting on their capital to accomplish access to HE, and they do this despite the highly complex nature of their lives and the structural barriers to access that were found including: finance, inadequate recognition of prior learning pathways, lengthy periods waiting for acceptance, and language needs. Based on the findings, there is evidence to indicate that the participants encountered a higher education system that did not always have their interests at heart. A richer understanding of first-generation migrant students’ experiences is necessary in order to promote equity and diversity in HE. Recommendations are made for policy, practice and future research