| Project Title |
Metastable neural dynamics in the functional connectome of the healthy neonate brain |
| Project Code |
HPC_19_01071 |
| Principal Investigator |
Dr Arun Bokde |
| Start Date |
2019-10-31 |
| End Date |
2020-05-31 |
| Abstract |
Introduction
Current theory proposes that healthy neural dynamics operate in a metastable regime, where brain regions interact to simultaneously maximize integration and segregation, yet little is known of how and when these dynamical properties arise (Tognoli and Kelso, 2014). Lesion studies can provide us with a better understanding of brain networks. In previous studies, they have been used to assess the structural robustness of cortical networks (Hagmann et al., 2007) and to better understand the human white matter connectome (Irimia and Van Horn, 2014). Moreover, they have previously been used to understand how lesion-induced changes can propogate throughout the whole network in the macaque brain (Honey & Sporns, 2008), and how graph theoretical properties of the lesioned regions relate in simulated and empirical neural dynamics (Alstott et al., 2009). Accordingly, this study seeks to examine the effect of lesions on synchrony and metastability in the neonate brain which has not yet been investigated.
Objective
The study aims to compare the coordinative interactions between the brains connectivity networks at rest in a cohort of healthy neonates and adults. Secondly, we wish to assess the resilience of brain networks by simulating the effect of lesions and their consequence on metastable neural dyanmics.
Analysis
Rs-fMRI data obtained from the developing human connectome project (N=400), and 100 unrelated adult participants from the HCP (N=100), will be used for the analysis (dHCP; Makropoulos et al., 2018, HCP; Van Essen et al., 2013). Resting state cortical networks will be defined using both the Schaefer 7 and 17 network parcellations (Schaefer et al., 2017). Additionally, subcortical networks will be included from the Automated anatomical labeling atlas (Shi et al., 2011, Tzourio-Mazoyer et al., 2002). For each network, synchrony and metastability will be computed using the Kuramoto order parameter and compared between the healthy neonate and adult group. For the lesion study, individual regions and all their connections will be quantified, and removed from the model in order to assess the effect of lesions on both global and local dynamics. |
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| Project Title |
Segmentation of hippocampus subfields in a longitudinal study with adolescents |
| Project Code |
HPC_19_01070 |
| Principal Investigator |
Dr Arun Bokde |
| Start Date |
2019-10-09 |
| End Date |
2020-02-29 |
| Abstract |
Depression in adolescence is a possible consequence of negative/stressful life events. The hippocampus and the amygdala are key regions to understand the development of depressive symptoms that lead to brain structural changes. With Freesurfer, I want to sub-divide the hippocampus in its subfields, and to obtain measures of their volume at three different stages of life, so that I will be able to compare possible changes between less and more stressed adolescents over time. This will lead to understand more what happens to the brain structures when adolescents live stressful experiences. |
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| Project Title |
Charge Transfer States in Organic LED's |
| Project Code |
HPC_19_01069 |
| Principal Investigator |
Dr Charles Patterson |
| Start Date |
2019-09-24 |
| End Date |
2020-06-01 |
| Abstract |
This project will use many body methods to calculate excitations in organic molecules with applications as organic light emitting diodes. It is being conducted as a final year project in Theoretical Physics. |
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| Project Title |
Magnetoelectricity in Ni-based Tellurates |
| Project Code |
HPC_19_01068 |
| Principal Investigator |
Prof Stefano Sanvito |
| Start Date |
2019-07-24 |
| End Date |
2020-07-24 |
| Abstract |
Multiferroics (MFs) are materials that can combine at least two primary ferroic properties: ferromagnetism, ferroelectricity and ferroelasticity. In the case of magnetoelectric (ME) MFs, coupling between ferroelectricity and ferromagnetism occurs. The understanding of the underlying quantum-level microscopic mechanisms that lead to ME coupling is essential for the engineering of novel ME MFs, since the ones already existing in nature are very limited. Spin-induced ferroelectrics manifest among the strongest ME effects ever recorded. In particular, the polar antiferromagnet Ni3TeO6 transcends the ME performance of all other single-phase MFs, because it exhibits non-hysteretic colossal ME coupling. A solid theoretical approach is essential for further insight in the fundamental physics hidden behind magnetoelectricity. On these grounds, we propose electronic and magnetic structure first principles calculations for Ni3TeO6, aiming at investigating the magnetocrystalline anisotropy and magnetic exchange interactions in Ni3TeO6. |
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| Project Title |
development of an on-chip optical frequency synthesizer |
| Project Code |
HPC_19_01066 |
| Principal Investigator |
Prof John Donegan |
| Start Date |
2018-01-01 |
| End Date |
2021-12-31 |
| Abstract |
With the help of a self-referenced optical frequency comb (OFC), optical frequencies can be controlled to the same precision as microwave frequencies. Currently self-referenced OFC systems are only available through bench-top setups such as a combination of femtosecond pulsed lasers, EDFAs, and highly nonlinear optical fiber. The whole setup is bulky, expensive and sensitive to environment changes. There is strong interest to miniaturize the whole setup to chip-scale so that a highly accurate optical frequency source would be cheap and easily available for applications such as a chip-scale optical clock, high spectral efficiency optical communications, and LiDAR. |
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| Project Title |
Eco-Metrics |
| Project Code |
HPC_19_01065 |
| Principal Investigator |
Prof Laurence Gill |
| Start Date |
2017-09-01 |
| End Date |
2020-09-30 |
| Abstract |
Due to the inaccessibility of many wetlands, there is a growing recognition that remote sensing techniques can be a viable and cost-effective alternative to field-based ecosystem monitoring. The objective of the study is to investigate the use of multispectral satellite imagery for delineating the extent of raised bogs and then monitoring their ecological composition in order to help with Ireland’s obligations under the EU Habitats Directive. Mere classification of the wetlands will not be helpful or practical until there is a scope of generalisation. In order to generalise the findings, the study suggests the usage of a convolutional neural network for image classification and pattern recognition of various species present inside the wetlands such as raised bogs. |
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| Project Title |
Abundance tomography of SNe Ia |
| Project Code |
HPC_19_01064 |
| Principal Investigator |
Dr Mark Magee |
| Start Date |
2019-07-16 |
| End Date |
2022-03-01 |
| Abstract |
Abundance tomography is used to map the composition of the ejecta in supernovae. This allows for the interrogration of which elements are produced and in what amounts, providing vital constraints on explosion models. This project will involve testing abundance tomography models of SNe Ia by calculating light curves. Comparisons between the model and observed light curves will demonstrate whether the current abundance tomography analysis is suitable. |
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| Project Title |
Effects of the 56Ni distribution |
| Project Code |
HPC_19_01063 |
| Principal Investigator |
Dr Mark Magee |
| Start Date |
2019-07-08 |
| End Date |
2021-02-28 |
| Abstract |
Despite being generally regarded as a homogeneous group, it is becoming increasingly evident that normal SNe Ia can show significant diversity. Differences in the explosion mechanisms and conditions are imprinted on the light curve shapes and colours, allowing for the interrogation of the physical conditions (density profile, composition, etc.) within the supernova. This project will investigate how differences in the nucleosynthesis of the explosion impacts the light curves and key physical parameters that have been neglected in previous studies.
I will present models calculated with our radiative transfer code and show that these may be used to provide constraints on the explosion mechanism for individual objects and to determine the exact explosion date. With these models in hand, I will also discuss what observations are necessary to constrain the properties of future objects. This will become increasingly important in future years, as upcoming surveys discover SNe at earlier times, and in greater numbers. |
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| Project Title |
Krylov Subspace Techniques for Unitary dynamics in complex quatum systems |
| Project Code |
HPC_19_01062 |
| Principal Investigator |
Prof John Goold |
| Start Date |
2019-06-13 |
| End Date |
2019-12-31 |
| Abstract |
The study of diverse dynamical properties in complex quantum chaotic systems is central in applications related to quantum technologies and has received a renovated interest, in part due to recent advances in, e.g., quantum computation and simulation, cold atom experiments and superconducting nanowires. These technologies ultimately rely on the ability to communicate information using a quantum system as a working medium and these studies are, therefore, crucial.
In this project, we use Krylov subspace techniques to carry out simulations of unitary quantum dynamics of complex and strongly interacting systems; which constitutes a powerful technique for studies of dynamical properties. Specifically, we are interested in physical systems that exhibit a many-body localisation transition, a demanding task that requires the study of both large systems and long-time dynamics. The analysis we propose provides a theoretical description in recent experiments using ultracold atoms and trapped ions in optical lattices.
The goal of this research is to numerically study the properties of many body quantum systems. In particular we study large-scale spin-1/2 chains, and rings, modelled by the XXZ Hamiltonian. The aim is study chains with up to thirty sites, this being computationally expensive requires the use of numerical techniques and massive parallelisation. The dynamics of characterisations of the spin chain, such as density profiles , fidelity, under time evolution are studied. An investigation into various observables will also be carried out. |
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| Project Title |
SERS |
| Project Code |
HPC_19_01061 |
| Principal Investigator |
Prof Parvaneh Mokarian-Tabari |
| Start Date |
2019-05-24 |
| End Date |
2020-05-24 |
| Abstract |
We want to simulate the electric near-field enhancement of a novel plasmonic slab. The later consist of a perforated gold film that is coupled with a Babinet complementary disk array. Hole film and disk array are seperated by silicone nanopillars. We want to correlate simulated results with experimental surface enhanced Raman spectroscopy (SERS) enhancement factors. The SERS templates are fabricated in our groupe by block copolymer lithography. |
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