cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Robust Classification using Hidden Markov Models and Mixtures of Normalizing Flows
Creators: name: Ghosh, Anubhab
name: Honoré, Antoine
name: Liu, Dong
name: Henter, Gustav Eje
name: Chatterjee, Saikat
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: We test the robustness of a maximum-likelihood (ML) based classifier where sequential data as observation is corrupted by noise. The hypothesis is that a generative model, that combines the state transitions of a hidden Markov model (HMM) and the neural network based probability distributions for the hidden states of the HMM, can provide a robust classification performance. The combined model is called normalizing-flow mixture model based HMM (NMM-HMM). It can be trained using a combination of expectation-maximization (EM) and backpropagation. We verify the improved robustness of NMM-HMM classifiers in an application to speech recognition.
description: 6 pages. Accepted at MLSP 2020
Plagiarism Detection in arXiv
Creators: name: Sorokina, Daria
name: Gehrke, Johannes
name: Warner, Simeon
name: Ginsparg, Paul
Publisher: name: arXiv
Year: 2007
Subjects: subject: Databases (cs.DB)
subject: Digital Libraries (cs.DL)
subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: We describe a large-scale application of methods for finding plagiarism in research document collections. The methods are applied to a collection of 284,834 documents collected by arXiv.org over a 14 year period, covering a few different research disciplines. The methodology efficiently detects a variety of problematic author behaviors, and heuristics are developed to reduce the number of false positives. The methods are also efficient enough to implement as a real-time submission screen for a collection many times larger.
description: Sixth International Conference on Data Mining (ICDM'06), Dec 2006
Cosmologies with Energy Exchange
Creators: name: Barrow, John D.
name: Clifton, T.
Publisher: name: arXiv
Year: 2006
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We provide a simple mathematical description of the exchange of energy between two fluids in an expanding Friedmann universe with zero spatial curvature. The evolution can be reduced to a single non-linear differential equation which we solve in physically relevant cases and provide an analysis of all the possible evolutions. Particular power-law solutions exist for the expansion scale factor and are attractors at late times under particular conditions. We show how a number of problems studied in the literature, such as cosmological vacuum energy decay, particle annihilation, and the evolution of a population of evaporating black holes, correspond to simple particular cases of our model. In all cases we can determine the effects of the energy transfer on the expansion scale factor. We also consider the situation in the presence of anti-decaying fluids and so called phantom fluids which violate the dominant energy conditions.
description: 12 pages, 1 figure
First-principles study of the robust superconducting state of NbTi alloys under ultrahigh pressures
Creators: name: Zhang, Jian-Feng
name: Gao, Miao
name: Liu, Kai
name: Lu, Zhong-Yi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A recent experiment reported that robust superconductivity appears in NbTi alloys under ultrahigh pressures with an almost constant superconducting $T_c$ of ~19 K from 120 to 261.7 GPa [J. Guo et al., Adv. Mater. 31, 1807240 (2019)], which is very rare among the known superconductors. We investigate the origin of this novel superconducting behavior in NbTi alloys based on density functional theory and density functional perturbation theory calculations. Our results indicate that the pressure tends to transform NbTi alloys from a random phase to a uniformly ordered crystal phase, and the exotic robust superconductivity of NbTi alloys can still be understood in the framework of BCS theory. The Nb element in NbTi alloys plays a dominant role in the superconductivity at low pressure, while the NbTi crystal with an alternative and uniform Nb and Ti atomic arrangement may be responsible for the stable superconductivity under high pressures. The robust superconducting transition temperature of NbTi under ultrahigh pressure can be explained by a synergistic effect of the enhanced phonon frequency, the modestly reduced total electron-phonon coupling, and the pressure-dependent screened Coulomb repulsion.
description: 7 pages, 5 figures, 1 table
Renormalizable parameters of the sine-Gordon model
Creators: name: Nagy, S.
name: Nandori, I.
name: Polonyi, J.
name: Sailer, K.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The well-known phase structure of the two-dimensional sine-Gordon model is reconstructed by means of its renormalization group flow, the study of the sensitivity of the dynamics on microscopic parameters. Such an analysis resolves the apparent contradiction between the phase structure and the triviality of the effective potential in either phases, provides a case where usual classification of operators based on the linearization of the scaling relation around a fixed point is not available and shows that the Maxwell-cut generates an unusually strong universality at long distances. Possible analogies with four-dimensional Yang-Mills theories are mentioned, too.
description: 12 pages, 7 figures. Revised form, to appear in Phys. Lett. B
Radflow: A Recurrent, Aggregated, and Decomposable Model for Networks of Time Series
Creators: name: Tran, Alasdair
name: Mathews, Alexander
name: Ong, Cheng Soon
name: Xie, Lexing
Publisher: name: arXiv
Year: 2021
Subjects: subject: Social and Information Networks (cs.SI)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: We propose a new model for networks of time series that influence each other. Graph structures among time series are found in diverse domains, such as web traffic influenced by hyperlinks, product sales influenced by recommendation, or urban transport volume influenced by road networks and weather. There has been recent progress in graph modeling and in time series forecasting, respectively, but an expressive and scalable approach for a network of series does not yet exist. We introduce Radflow, a novel model that embodies three key ideas: a recurrent neural network to obtain node embeddings that depend on time, the aggregation of the flow of influence from neighboring nodes with multi-head attention, and the multi-layer decomposition of time series. Radflow naturally takes into account dynamic networks where nodes and edges change over time, and it can be used for prediction and data imputation tasks. On real-world datasets ranging from a few hundred to a few hundred thousand nodes, we observe that Radflow variants are the best performing model across a wide range of settings. The recurrent component in Radflow also outperforms N-BEATS, the state-of-the-art time series model. We show that Radflow can learn different trends and seasonal patterns, that it is robust to missing nodes and edges, and that correlated temporal patterns among network neighbors reflect influence strength. We curate WikiTraffic, the largest dynamic network of time series with 366K nodes and 22M time-dependent links spanning five years. This dataset provides an open benchmark for developing models in this area, with applications that include optimizing resources for the web. More broadly, Radflow has the potential to improve forecasts in correlated time series networks such as the stock market, and impute missing measurements in geographically dispersed networks of natural phenomena.
description: Published in The Web Conference 2021. Code is available at https://github.com/alasdairtran/radflow
Παρασκευή και χαρακτηρισμός διμεταλλικών ηλεκτροκαταλυτών Pt-Ir για ηλεκτρόδια οξυγόνου διπλής λειτουργικότητας (έκλυσης/αναγωγής οξυγόνου)
Creators: name: Ματούλη, Ιωάννα Κωνσταντίνου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Γαλβανική αντικατάσταση
Καταλύτες Pt, Ir
Ηλεκτρόδια διπλής λειτουργίας
Galvanic replacement
Pt, Ir catalysts
Bifunctional electrodes

description: Η παρούσα εργασία παρουσιάζει την παρασκευή διμεταλλικών αποθεμάτων PtIr(Ni) με τη μέθοδο της γαλβανικής αντικατάστασης, σε ηλεκτροδιακά υποστρώματα προαποτεθέντος Ni (πάχους μερικών εκατοντάδων nm) σε υποστρώματα υαλώδους άνθρακα (glassy carbon, GC). Η παρασκευή αυτών πραγματοποιήθηκε με δυο τρόπους: α) με διαδοχική απόθεση του Ir κι έπειτα του Pt (από διαφορετικά διαλύματα), στο προαποτεθέν Ni πάνω στο υπόστρωμα GC και β) από την παρασκευή μικτού διαλύματος Ir και Pt στο οποίο εμβαπτίστηκε το ηλεκτρόδιο GC με το προαποτεθέν σε αυτό Ni. Η αυθόρμητη μερική αντικατάσταση του Ni από Pt και Ir οδήγησε σε ηλεκτρόδια PtIr(Ni)/GC των οποίων η σύσταση και επιφανειακή μορφολογία μελετήθηκαν με τη χρήση των φασματοσκοπικών τεχνικών EDS, XPS και της μικροσκοπίας SEM αντίστοιχα. Τα αποτελέσματα από την επιφανειακή ηλεκτροχημεία των αποθεμάτων PtIr(Ni) αποδεικνύουν την έντονη εξάρτηση της αναλογίας Ir:Pt στο τελικό απόθεμα, από το λόγο των πρόδρομων συγκεντρώσεων στο διάλυμα ανταλλαγής και το χρόνο εμβάπτισης του υποστρώματος σε αυτό. Ο Pt είναι καλός καταλύτης για την αντίδραση αναγωγής οξυγόνου και το Ir αντίστοιχα, καλός καταλύτης για την αντίδρασης έκλυσης οξυγόνου. Το μικτό αποτέλεσμα που αποφέρει ο συνδυασμός των δυο παραπάνω στοιχείων, εξασφαλίζει ένα ηλεκτροκαταλυτικό σύστημα που μπορεί να χρησιμοποιηθεί ως ηλεκτρόδιο οξυγόνου σε μια αναγεννώμενη κυψέλη καυσίμου
description: This work presents the preparation of bimetallic PtIr(Ni) layers by a galvanic replacement method whereby Ni electrodeposited on glassy carbon substrates . They were prepared in two ways a) by sequential deposition of Ir and then Pt (from different solutions) at Ni electrodeposited layer and b) from the preparation of a mixed solution of Ir and Pt in which the GC electrode was immersed with the Ni electrodeposited therein. The spontaneous partial replacement of Ni by Pt and Ir resulted in PtIr(Ni)/GC electrodes whose composition and surface morphology were studied using EDS, XPS spectroscopic techniques and SEM technique respectively. The results from surface electrochemistry of PtIr(Ni) deposits, demonstrate the strong dependence of Ir ÷ Pt ratio on the final deposit by the ratio of precursor in the exchange solution. Pt and Ir are the best catalysts for the oxygen reduction and evolution reaction respectively. The mixed PtIr(Ni) electrocatalyst provides an electrocatalytic component that can be used in a regenerative fuel cell
Quark and lepton flavor model with leptoquarks in a modular $A_4$ symmetry
Creators: name: Nomura, Takaaki
name: Okada, Hiroshi
name: Orikasa, Yuta
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We propose a quark-lepton model via leptoquarks and modular $A_4$ symmetry. Since the neutrino mass is induced at one-loop level mediated by down quarks as well as leptoquarks, we have to explain lepton and quark masses and mixings with a single modulus $τ$. Here, we find predictions for lepton and quark sectors with unified modulus $τ$, and show several constraints originating from leptoquarks.
description: 23 pages, 8 figures, 4 tables
Protostar Formation in Magnetic Molecular Clouds beyond Ion Detachment: I. Formulation of the Problem and Method of Solution
Creators: name: Tassis, Konstantinos
name: Mouschovias, Telemachos Ch.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We formulate the problem of the formation of magnetically supercritical cores in magnetically subcritical parent molecular clouds, and the subsequent collapse of the cores to high densities, past the detachment of ions from magnetic field lines and into the opaque regime. We employ the six-fluid MHD equations, accounting for the effects of grains (negative, positive and neutral) including their inelastic collisions with other species. We do not assume that the magnetic flux is frozen in any of the charged species. We derive a generalized Ohm's law that explicitly distinguishes between flux advection (and the associated process of ambipolar diffusion) and Ohmic dissipation, in order to assess the contribution of each mechanism to the increase of the mass-to-flux ratio of the central parts of a collapsing core and possibly to the resolution of the magnetic flux problem of star formation. We show how our formulation is related to and can be transformed into the traditional, directional formulation of the generalized Ohm's law, and we derive formulae for the perpendicular, parallel and Hall conductivities entering the latter, which include, for the first time, the effect of inelastic collisions between grains. In addition, we present a general (valid in any geometry) solution for the velocities of charged species as functions of the velocity of the neutrals and of the effective flux velocity (which can in turn be calculated from the dynamics of the system and Faraday's law). The last two sets of formulae can be adapted for use in any general non-ideal MHD code to study phenomena beyond star formation in magnetic clouds. The results, including a detailed parameter study, are presented in two accompanying papers.
description: 17 pages, emulateapj; accepted for publication in the Astrophysical Journal
Ανάλυση συναισθήματος σε ελληνικά κείμενα από κοινωνικά δίκτυα με χρήση αλγορίθμων στατιστικής μάθησης
Creators: name: Πάντογλου, Δημήτριος Νικολάου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Ανάλυση Συναισθήματος
Επεξεργασία Φυσικής Γλώσσας
Στατιστική Μάθηση
Sentiment Analysis
Natural Language Processing
Statistical Learning

description: Η ανάλυση συναισθήματος την τελευταία δεκαετία δεν έχει εξελιχθεί μόνο σαν ένα πολύ σημαντικό πεδίο έρευνας, αλλά και σαν μια ραγδαία αναπτυσσόμενη βιομηχανία. Αυτό συμβαίνει καθώς υπάρχουν πολλοί τομείς που επωφελούνται από τα αποτελέσματά της, όπως το μάρκετινγκ, η ανάλυση ειδήσεων, προβλέψεις χρηματιστηρίου, πολιτική ανάλυση κ.ά.. Ωστόσο, η περισσότερη δουλειά σε αυτόν τον τομέα έχει γίνει στην αγγλική γλώσσα με αποτέλεσμα έρευνες σε άλλες γλώσσες να βρίσκονται σε πιο πρώιμο στάδιο. Οπότε, το βασικό κίνητρο για αυτήν την εργασία είναι να εφαρμοστούν κάποιες από τις κυριότερες τεχνικές ανάλυσης συναισθήματος σε ελληνικά κείμενα και να συζητηθούν κάποια από τα θέματα που προέκυψαν με σκοπό να εδραιωθεί ουσιαστικότερη έρευνα στο μέλλον. Με αυτό σαν πυξίδα, πραγματοποιήθηκε μια περιεκτική επισκόπηση του τομέα της ανάλυσης συναισθήματος, καθώς επίσης και των εφαρμογών της και των δυσκολιών της. Στη συνέχεια αναπτύχθηκε ένα βαθμολογημένο σύνολο δεδομένων με tweets και εφαρμόστηκαν κάποιες τεχνικές προεπεξεργασίας κειμένου. Τέλος, έγινε εφαρμογή ενός μοντέλου απλού Bayes και ανάλυση των αποτελεσμάτων
description: Sentiment Analysis has not only become a hot research field over the last decade, but also a booming industry, because of the wide variety of applications that could benefit from its results, such as marketing, news analytics, stock market predictions, political analysis and so on. While most of the work done in this field focuses in applications in the English language, and for good reason, not much has been done in other languages. So, the primary motivation of this thesis is to apply some of the most popular Sentiment Analysis techniques and methods in texts written in Greek and discuss some of the issues that emerged as a way to facilitate further research in the future. To this end, a comprehensive survey of the field of Sentiment Analysis, as well as its applications and challenges is performed. Then, a labeled dataset containing tweets for Sentiment Analysis is developed and some text pre-processing techniques are applied. Lastly, a Naïve Bayes classifier is trained and tested, and results are being analysed and discussed
Calibrating X-ray binary luminosity functions via optical reconnaissance I. The case of M83
Creators: name: Hunt, Qiana
name: Gallo, Elena
name: Chandar, Rupali
name: Mulia, Paula Johns
name: Mok, Angus
name: Prestwich, Andrea
name: Liu, Shengchen
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Building on recent work by Chandar et al. (2020), we construct X-ray luminosity functions (XLFs) for different classes of X-ray binary (XRB) donors in the nearby star-forming galaxy M83 through a novel methodology: rather than classifying low- vs. high-mass XRBs based on the scaling of the number of X-ray sources with stellar mass and star formation rate, respectively, we utilize multi-band Hubble Space Telescope imaging data to classify each Chandra-detected compact X-ray source as a low-mass (i.e. donor mass ~ 8 solar masses) or intermediate-mass XRB based on either the location of its candidate counterpart on optical color-magnitude diagrams or the age of its host star cluster. In addition to the the standard (single and/or truncated) power-law functional shape, we approximate the resulting XLFs with a Schechter function. We identify a marginally significant (at the 1-to-2 sigma level) exponential downturn for the high-mass XRB XLF, at logLx ~ 38.48^{+0.52}_{-0.33} (in log CGS units). In contrast, the low- and intermediate-mass XRB XLFs, as well as the total XLF of M83, are formally consistent with sampling statistics from a single power-law. Our method suggests a non-negligible contribution from low- and possibly intermediate-mass XRBs to the total XRB XLF of M83, i.e. between 20 and 50%, in broad agreement with X-ray based XLFs. More generally, we caution against considerable contamination from X-ray emitting supernova remnants to the published, X-ray based XLFs of M83, and possibly all actively star-forming galaxies.
description: 18 pages (text, 44 with figures), 8 figures + 1 long figure, 1 table + 1 long table. Accepted by ApJ
Current-induced magnetization switching in MgO barrier based magnetic tunnel junctions with CoFeB/Ru/CoFeB synthetic ferrimagnetic free layer
Creators: name: Hayakawa, Jun
name: Ikeda, Shoji
name: Lee, Young Min
name: Sasaki, Ryutaro
name: Meguro, Toshiyasu
name: Matsukura, Fumihiro
name: Takahashi, Hiromasa
name: Ohno, Hideo
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We report the intrinsic critical current density (Jc0) in current-induced magnetization switching and the thermal stability factor (E/kBT, where E, kB, and T are the energy potential, the Boltzmann constant, and temperature, respectively) in MgO based magnetic tunnel junctions with a Co40Fe40B20(2nm)/Ru(0.7-2.4nm)/Co40Fe40B20(2nm) synthetic ferrimagnetic (SyF) free layer. We show that Jc0 and E/kBT can be determined by analyzing the average critical current density as a function of coercivity using the Slonczewski's model taking into account thermal fluctuation. We find that high antiferromagnetic coupling between the two CoFeB layers in a SyF free layer results in reduced Jc0 without reducing high E/kBT.
description: 16 pages, 4 figures. Jpn. J. Appl. Phys., in press
Do consumption-based asset pricing models explain own-history predictability in stock market returns?
Creators: name: Ashby, M.
name: Linton, O. B.
Publisher: name: Faculty of Economics, University of Cambridge
Year: 2022
Subjects: consumption-based asset pricing models
serial correlation
predictability
martingale difference sequence
variance ratio
quantilogram
rescaled range
power spectrum
MIDAS

description: We show that three prominent consumption-based asset pricing models - the Bansal-Yaron, Campbell-Cochrane and Cecchetti-Lam-Mark models - cannot explain the own-history predictability properties of stock market returns. We show this by estimating these models with GMM, deriving ex-ante expected returns from them and then testing whether the difference between realised and expected returns is a martingale difference sequence, which it is not. Furthermore, semi-parametric tests of whether the models' state variables are consistent with the degree of own-history predictability in stock returns suggest that only the Campbell-Cochrane habit variable may be able to explain return predictability, although the evidence on this is mixed.
The model of particle production by strong external sources
Creators: name: Dremin, I. M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Using some knowledge of multiplicity disributions for high energy reactions, it is possible to propose a simple analytical model of particle production by strong external sources. The model describes qualitatively most peculiar properties of the distributions. The generating function of the distribution varies so drastically as it can happen at phase transitions.
description: 7 pages, no Figures, LATEX; Eq. (10) corrected, Eqs (25), (26) added, ref [20] corrected; Pisma v Zhetf 84, n5 (2006)
Hot topics in global health: Alignment of global health education delivery using an interspeciality cross-collaborative approach
Creators: name: D'Souza, Amrita
name: Chapman, Arabella
name: Apichaya Amrapala
name: Davies, Thomas
name: Orhan, Orhan
Publisher: name: F1000 Research Limited
Year: 2024

description: Background:

Most UK postgraduate specialities list Global Health on their Royal College curricula to varying degrees. However, there is no formalised Global Health Education (GHE) training to achieve this within most specialities, and no recommended method of GHE delivery to UK medical postgraduates by the Royal Colleges.

This project set out to address this gap in GHE delivery to meet trainees’ curricular needs by delivering a 2-day international Global Health conference in May 2024.



Summary of Work:

Hot Topics in Global Health was designed against Walpole and Al-Shakarchi's et al's frameworks of GHE core competencies for UK postgraduate trainees, the only two frameworks outlining UK GHE competencies to date.

Speakers include Royal College Global teams, UK NGOs and UK Tropical Medicine institutes. This is a novel UK Global Health conference promoting cross-specialty collaborative learning on Global Health across medical and surgical specialities. A Registration of Interest form sent to all interested attendees has scoped learner-identified needs, which are being addressed through carefully-planned sessions.



Summary of Results:

168 professionals have registered interest with 126 preferring both days in-person attendance; including Foundation Trainees (28), SHOs (60), Registrars (59), SAS (7), Consultants (10) and AHPs (4). Attendees are across a wide array of specialities.

Learner-identified GHE needs include climate change, LGBT+ health inequalities, social media’s impact on global mental health, healthcare decolonisation, digitalisation of primary care in low-resource settings, alternative therapies, and planetary health. This has been highlighted to speakers in advance so learning needs are met.



Discussion & Conclusion:

This GHE initiative aims to provide high-quality training to fill the current gap in UK GHE delivery that meets curricular needs. Learner-identified GHE needs have evolved since Walpole et al’s 2016 framework reflecting global affairs, particularly climate change.

Inter-speciality educational collaboratives benefit learning and are aligned with the cross-speciality collaborative approach needed in global healthcare delivery.



Take Home Message:

We will pilot Hot Topics in Global Health in May 2024 as a novel cross-speciality GHE initiative and evaluate UK trainees’ perceptions on GHE delivery to establish a yearly UK GHE conference meeting postgraduates’ needs.
Η σχέση μεταξύ εικαστικών καλλιτεχνών και εικαστικών επιμελητών
Creators: name: Λιούτας, Θωμάς Αστερίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Επιμελητής
Εικαστικός καλλιτέχνης
Σύγχρονη επιμέλεια
Εικαστικές τέχνες
Curator
Visual Artist
Contemporary curating
Visual Arts

description: Η παρούσα μεταπτυχιακή διπλωματική εργασία εστιάζει στο σύγχρονο τοπίο των εικαστικών τεχνών, ερευνώντας δύο από τους βασικούς δρώντες, τους εικαστικούς καλλιτέχνες και τους εικαστικούς επιμελητές. Σκοπός της είναι να αναδείξει την περίπλοκη σχέση που έχει αναπτυχθεί και συνεχίζει να αναπτύσσεται μεταξύ τους, διερευνώντας σημεία που προκαλούν προβληματισμό και ανιχνεύοντας τόσο θετικά στοιχεία, όσο και πιθανές παθογένειες. Για την εύρεση των αποτελεσμάτων ακολουθήθηκε η ποιοτική μέθοδος, και συγκεκριμένα η διενέργεια συνεντεύξεων. Οι συνεντεύξεις ήταν ημιδομημένου τύπου και πραγματοποιήθηκαν με 3 επιμελητές και 7 εικαστικούς καλλιτέχνες. Οι συνεντεύξεις αυτές αποτιμήθηκαν και έδωσαν ιδιαίτερα ενδιαφέροντα αποτελέσματα σε σχέση με τα ευρήματα της διεθνούς βιβλιογραφίας που μελετήθηκε. Συγκεκριμένα, φαίνεται ότι υπάρχουν αρκετές διαφωνίες μεταξύ εικαστικών καλλιτεχνών και επιμελητών, οι οποίες εστιάζουν κυρίως στον ρόλο που οφείλουν να διαδραματίζουν οι επιμελητές στο πεδίο των εικαστικών τεχνών. Η αυξημένη ισχύς που έχουν οι επιμελητές σε αυτόν τον χώρο φαίνεται να είναι πηγή προβληματισμού για τους εικαστικούς καλλιτέχνες, ενώ παράλληλα αναδύεται ένα μεγάλο ζήτημα ρευστότητας και ασάφειας μεταξύ αυτών των ρόλων. Το τελευταίο είναι γνωστό στη διεθνή βιβλιογραφία, αλλά δεν είχε αποσαφηνιστεί πλήρως κατά πόσο είναι μία εν δυνάμει πηγή προβλημάτων, που μπορεί να δημιουργήσει σύγχυση και προβληματικές τριβές μεταξύ εικαστικών καλλιτεχνών και επιμελητών
description: The present thesis focuses on the field of contemporary visual arts, researching two of the main protagonists: the visual artists and the curators. The aim is to address the complicated relationship that has been formed between them, while unearthing elements that are possible reasons for concern, healthy practices and possible ills. The chosen method for this research were semi-structured interviews, that were conducted with 3 curators and 7 visual artists, with the interviews being evaluate while also considering the findings of the literature on the topic. The results indicate that there is discord between visual artists and curators, mainly focused on the curatorial role. The growing influence of the curators is proposed a concern amongst visual artists, while there is also an issue of ambiguity. The last has already been noticed in the literature, but it had not been adequately explored as a reason for conflicts between artists and curators
Aspects relating to the spread and survival of Phellinus root rot
Creators: name: Rusch, David R.
Publisher: name: University of British Columbia
Year: 2008

description: Active and inactive edges of a Phellinus weirii root rot center were compared to see if the reason for the inactivation of part of the center could be explained. The inactivation could not be shown to be the result of differences in root contacts or soil factors. Hypovirulence caused by a dsRNA virus was also investigated as a possible cause for the inactivation of Phellinus root rot centers. A survey of several isolates of P. weirii from British Columbia and the United States failed to reveal the presence of dsRNA in any of the isolates. The possible role of zone lines in the survival of P. weirii was also investigated. The rate of moisture loss from Douglas-fir blocks with and without zone lines was compared to see if zone lines slow the rate of moisture loss from decayed wood. No significant differences (alpha = 0.05) could be detected in the rate of moisture loss of blocks with and without zone lines.
Protostar Formation in Magnetic Molecular Clouds beyond Ion Detachment: II. Typical Axisymmetric Solution
Creators: name: Tassis, Konstantinos
name: Mouschovias, Telemachos Ch.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We follow the ambipolar-diffusion--driven formation and evolution of a fragment in a magnetically supported molecular cloud, until a hydrostatic protostellar core forms at its center. This problem was formulated in Paper I. We determine the density, velocity and magnetic field as functions of space and time, and the contribution of ambipolar diffusion and Ohmic dissipation to the resolution of the magnetic flux problem of star formation. The issue of whether the magnetic field ever decouples from the (neutral) matter is also addressed. We also find that the electrons do not decouple from the field lines before thermal ionization becomes important and recouples the magnetic field to the neutral matter. Ohmic dissipation becomes more effective than ambipolar diffusion as a flux reduction mechanism only at the highest densities (a few times 10^12 particles per cubic cm). In the high-density central parts of the core, the magnetic field acquires an almost spatially uniform structure, with a value that, at the end of the calculation (number density ~ 5 times 10^14 particles per cubic cm), is found to be in excellent agreement with meteoritic measurements of magnetic fields in the protosolar nebula. Outside the hydrostatic protostellar core, a concentration of magnetic flux (a "magnetic wall") forms, which gives rise to a magnetic shock. This magnetic shock is the precursor of the repeated shocks found by Tassis & Mouschovias (2005) which cause spasmodic accretion onto the hydrostatic core at later times.
description: 15 pages, 12 figures, emulateapj; accepted for publication in the Astrophysical Journal
title: Evaluation of high-resolution video technology as a pedagogical approach for peripheral intravenous cannulation teaching and simulation in nursing education. A mixed action research project
Creators: name: Hernon, Orlaith
Publisher: name: University of Galway
Year: 2024
Subjects: subject: Medicine Nursing and Health Sciences
subject: Nursing
subject: FOS: Health sciences
subject: Pedagogy
subject: Video technology
subject: Intravenous Cannulation
subject: Teaching
subject: Nursing education

description: The main objective in nurse education is to develop student nurses’ competencies as they progress and transition to become registered nurses. Nursing programmes identify core competencies which include knowledge, clinical decision making, attitudes, and clinical skills that student nurses are expected to acquire by the time they finish their educational studies. Registered nurses are expected to perform the skill of venepuncture and peripheral intravenous cannulation, yet few countries ensure this clinical skill is a learning outcome of the undergraduate curriculum. As a result of this phenomenon, the training of these skills is often left until students become graduates and registered professionals. In Ireland, the Office of Nursing and Midwifery Service Directive (2020) updated the Undergraduate Nursing and Midwifery Curriculum to include the teaching of the clinical procedures, venepuncture, and peripheral intravenous cannulation. The aim of the work presented in this thesis was to develop, implement and evaluate a technology-driven pedagogical approach to teach and assess students on these skills. Aligning with the goal to ensure adequately prepared, highly skilled nurses who provide high quality, safe care to patients, the intended outcome of this study was to improve the knowledge, skills, and attitudes of student nurses in performing these specific skills.
Building Safer Autonomous Agents by Leveraging Risky Driving Behavior Knowledge
Creators: name: Rana, Ashish
name: Malhi, Avleen
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Simulation environments are good for learning different driving tasks like lane changing, parking or handling intersections etc. in an abstract manner. However, these simulation environments often restrict themselves to operate under conservative interaction behavior amongst different vehicles. But, as we know, real driving tasks often involve very high risk scenarios where other drivers often don't behave in the expected sense. There can be many reasons for this behavior like being tired or inexperienced. The simulation environment doesn't take this information into account while training the navigation agent. Therefore, in this study we especially focus on systematically creating these risk prone scenarios with heavy traffic and unexpected random behavior for creating better model-free learning agents. We generate multiple autonomous driving scenarios by creating new custom Markov Decision Process (MDP) environment iterations in the highway-env simulation package. The behavior policy is learnt by agents trained with the help from deep reinforcement learning models. Our behavior policy is deliberated to handle collisions and risky randomized driver behavior. We train model free learning agents with supplement information of risk prone driving scenarios and compare their performance with baseline agents. Finally, we casually measure the impact of adding these perturbations in the training process to precisely account for the performance improvement obtained from utilizing the learnings from these scenarios.
description: Published in CCCI 2021, Best Paper Award in Informatics
Splitting of doubly quantized vortices in dilute Bose-Einstein condensates
Creators: name: Gawryluk, K.
name: Karpiuk, T.
name: Brewczyk, M.
name: Rzazewski, K.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We investigate the dynamics of doubly charged vortices generated in dilute Bose-Einstein condensates by using the topological phase imprinting technique. We find splitting times of such vortices and show that thermal atoms are responsible for their decay.
description: 1 page, 1 figure
The first multi-wavelength campaign of AXP 4U 0142+61 from radio to hard X-rays
Creators: name: Hartog, P. R. den
name: Kuiper, L.
name: Hermsen, W.
name: Rea, N.
name: Durant, M.
name: Stappers, B.
name: Kaspi, V. M.
name: Dib, R.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: For the first time a quasi-simultaneous multi-wavelength campaign has been performed on an Anomalous X-ray Pulsar from the radio to the hard X-ray band. 4U 0142+61 was an INTEGRAL target for 1 Ms in July 2005. During these observations it was also observed in the X-ray band with Swift and RXTE, in the optical and NIR with Gemini North and in the radio with the WSRT. In this paper we present the source-energy distribution. The spectral results obtained in the individual wave bands do not connect smoothly; apparently components of different origin contribute to the total spectrum. Remarkable is that the INTEGRAL hard X-ray spectrum (power-law index 0.79 +/- 0.10) is now measured up to an energy of ~230 keV with no indication of a spectral break. Extrapolation of the INTEGRAL power-law spectrum to lower energies passes orders of magnitude underneath the NIR and optical fluxes, as well as the low ~30 microJy (2 sigma) upper limit in the radio band.
description: 6 pages, 1 figure. To be published in the proceedings of the conference "Isolated Neutron Stars: from the Interior to the Surface" (April 24-28, 2006, London, UK), eds. S. Zane, R. Turolla and D. Page
A tight lower bound on the matching number of graphs via Laplacian eigenvalues
Creators: name: Gu, Xiaofeng
name: Liu, Muhuo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C50 05C70

description: Let $α'$ and $μ_i$ denote the matching number of a non-empty simple graph $G$ with $n$ vertices and the $i$-th smallest eigenvalue of its Laplacian matrix, respectively. In this paper, we prove a tight lower bound $$α' \ge \min\left\{\Big\lceil\frac{μ_2}{μ_n} (n -1)\Big\rceil,\ \ \Big\lceil\frac{1}{2}(n-1)\Big\rceil \right\}.$$ This bound strengthens the result of Brouwer and Haemers who proved that if $n$ is even and $2μ_2 \ge μ_n$, then $G$ has a perfect matching. A graph $G$ is factor-critical if for every vertex $v\in V(G)$, $G-v$ has a perfect matching. We also prove an analogue to the result of Brouwer and Haemers mentioned above by showing that if $n$ is odd and $2μ_2 \ge μ_n$, then $G$ is factor-critical. We use the separation inequality of Haemers to get a useful lemma, which is the key idea in the proofs. This lemma is of its own interest and has other applications. In particular, we prove similar results for the number of balloons, spanning even subgraphs, as well as spanning trees with bounded degree.
description: The first manuscript was done in May 2020, and the current manuscript was accepted by European Journal of Combinatorics in October 2021
title: Teaching old cells new tricks
Creators: name: Schlosser, Gerhard
Publisher: name: CRC Press
Year: 2021
Subjects: subject: Cells
subject: homology
subject: sensory evolution

description: This second introductory chapter clarifies conceptual issues relating to homology and evolutionary innovation and illustrates them with examples from sensory evolution. The first part of the chapter introduces the general concepts of character identity, homology and evolutionary innovation, while the second part applies these general concepts to the evolution of cell types. It is argued that characters can only be tracked through evolving lineages (allowing to identify homologs), if characters are conceptualized as independently evolving units. This in turn requires that characters are genetically individuated, meaning that they have at least a partially different genetic basis from other characters. Cell types are then introduced as a particular kind of independently evolving unit (or character). The identity of a cell type is typically determined by a core regulatory network (CoRN) of cross-regulating genes (often encoding transcription factors). Cell types in different species remain the same (homologous) as long as they retain the same CoRN, even though downstream target genes may change. Novel cell types originate, when a new CoRN is established either by duplication and divergence of a preexisting CoRN or by recombination and redeployment of genes previously used for other functions.
The challenges of changing teaching assistants' grading practices: Requiring students to show evidence of understanding
Creators: name: Marshman, Emily
name: Sayer, Ryan
name: Henderson, Charles
name: Yerushalmi, Edit
name: Singh, Chandralekha
Publisher: name: arXiv
Year: 2021
Subjects: subject: Physics Education (physics.ed-ph)
subject: FOS: Physical sciences

description: Teaching assistants (TAs) are often responsible for grading in introductory physics courses at large research universities. Their grading practices can shape students' approaches to problem solving and learning. Physics education research recommends grading practices that encourage students to provide evidence of understanding via explication of the problem-solving process. However, TAs may not necessarily grade in a manner that encourages students to provide evidence of understanding in their solutions. Within the context of a semester-long TA professional development course, we investigated whether encouraging TAs to use a grading rubric that appropriately weights the problem-solving process and having them reflect upon the benefits of using such a rubric prompts TAs to require evidence of understanding in student solutions. We examined how the TAs graded realistic student solutions to introductory physics problems before they were provided a rubric, whether TAs used the rubric as intended, whether they were consistent in grading similar solutions, and how TAs' grading criteria changed after discussing the benefits of a well-designed rubric. We find that many TAs typically applied the rubric consistently when grading similar student solutions but did not require students to provide evidence of understanding. TAs' written responses, class discussions, and individual interviews suggest that the instructional activities involving the grading rubrics in this study were not sufficient to change their grading practices. Interviews and class discussions suggest that helping TAs value a rubric that appropriately weights the problem-solving process may be challenging partly due to the TAs past educational experiences and the departmental context.
description: 18 pages
title: The application of continuous flow chemistry in the synthesis of iminosugars and c-glycosyl compounds
Creators: name: Bennett, Jack
Publisher: name: University of Galway
Year: 2024
Subjects: subject: Biological and Chemical Sciences
subject: Continuous flow chemistry
subject: Iminosugars
subject: C-glycosyl compounds
subject: Chemistry

description: Flow chemistry is a field of chemical synthesis which involves carrying out reactions in continuous streams of solvents. Despite the numerous potential advantages, flow chemistry has been applied in a limited number of areas in synthetic glycochemistry, such as oligosaccharide synthesis and deprotection steps. The main aim of this thesis is to apply continuous flow techniques in other areas of synthetic glycochemistry, and to provide a comparison with batch techniques for the reactions studied. Chapter 1 introduces carbohydrates and iminosugars, which are the main synthetic focus of this work. The bioactivity of iminosugars and major synthetic routes towards these substances are described. An overview of flow chemistry, its advantages over batch techniques and its application to date in glycochemistry is also included. Chapter 2 focuses on flow syntheses of iminosugars adapted from existing batch methods. This chapter includes a flow synthesis of 1-deoxynojirimycin (1-DNJ) and miglustat from an L-sorbose derivative, along with the synthesis of a C-glycosyl mannonojirimycin compound via cascade azide-alkene cycloaddition/aziridine formation/ring opening. Different protecting groups were also investigated for the synthesis of the mannonojirimycin structure. Chapter 3 describes the synthesis of new iminosugars in batch and flow, including protected deoxymannonojirimycin (DMJ) and L-DNJ structures via tandem intramolecular azide-alkene cycloaddition/aziridine formation/ring opening reactions. A Design of Experiments (DoE) study to improve the yield of the L-DNJ compound is discussed, and further attempts to improve yield via photosynthetic methods in batch and thermolysis in flow are also described. Additional synthetic modifications to the azide-alkene precursor with an aim to improve yield are also discussed. The main achievement was the development of a route to l-DNJ from D-xylose, which is also a new sequence. Chapter 4 details the application of cascade Wittig/intramolecular oxa-Michael additions to synthesise 2-(C-glycosyl)acetates under continuous flow conditions, from commercially available pyranoses. Access to higher temperatures in flow enabled the synthesis of these C-glycosyl compounds, while batch attempts are mostly unsuccessful using this method. A modified flow approach involving delayed addition of base (DBU), which further increased yields, is also described in this chapter. The flow synthesis of a precursor to b-D-galactopyranosyl-2-methylpropane, an inducer of protein synthesis in E. coli, is also described.
title: Novel construction of Specht modules for Monomial groups
Creators: name: Paul, Koushik
Publisher: name: University of Galway
Year: 2024
Subjects: subject: Symmetric Groups
subject: Monomial Groups
subject: Hyperoctahedral Groups
subject: Specht Matrices
subject: Specht Modules
subject: Simultaneous Multihistograms
subject: Polymultitabloids
subject: Mathematical and Statistical Sciences
subject: Mathematics
subject: FOS: Mathematics

description: In this thesis, I introduce a new method for constructing Specht modules using Specht matrices for families of symmetric groups, monomial groups, and hyperoctahedral groups. Specht modules are central to the representation theory of symmetric groups, connected to the concepts of Young symmetrizers and the subsequent development of polytabloids. These polytabloids form a basis for the Specht module associated with a particular partition of a natural number. In this work, I introduce a new combinatorial approach to replace polytabloids with columns of Specht matrices. The columns corresponding to the standard tableaux of shape λ, where λ is a partition of n ∈ N, form the basis of the Specht module S λ . This new construction is straightforward and easy to grasp, as it relies on basic linear algebra techniques, such as solving systems of linear equations. A longstanding open question in the representation theory of finite groups is whether a base change matrix can be found for a finite group G that transforms permutation matrices corresponding to irreducible representations into block forms. My thesis addresses this question for specific families of finite groups, including symmetric groups, monomial groups, and hyperoctahedral groups. It shows that a submatrix of the Specht matrix serves as a base change matrix that accomplishes this transformation, enabling us to obtain all irreducible representations of these groups over C. The methodologies employed in this thesis are computational, involving the development of several algorithms and computer programs to support the theoretical work. These have been implemented in the computer algebra system GAP (version 4).
Universal semiclassical equations based on the quantum metric
Creators: name: Leblanc, C.
name: Malpuech, G.
name: Solnyshkov, D. D.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We derive semiclassical equations of motion for an accelerated wavepacket in a two-band system. We show that these equations can be formulated in terms of the static band geometry described by the quantum metric. We consider the specific cases of the Rashba Hamiltonian with and without a Zeeman term. The semiclassical trajectories are in full agreement with the ones found by solving the Schrödinger equation. This formalism successfully describes the adiabatic limit and the anomalous Hall effect traditionally attributed to Berry curvature. It also describes the opposite limit of coherent band superposition giving rise to a spatially oscillating Zitterbewegung motion. At $k=0$, such wavepacket exhibits a circular trajectory in real space, with its radius given by the square root of the quantum metric. This quantity appears as a universal length scale, providing a geometrical origin of the Compton wavelength.