cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
High-Velocity Features in Type Ia Supernova Spectra
Creators: name: Childress, Michael J.
name: Filippenko, Alexei V.
name: Ganeshalingam, Mohan
name: Schmidt, Brian P.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We use a sample of 58 low-redshift (z <= 0.03) Type Ia supernovae (SNe Ia) having well-sampled light curves and spectra near maximum light to examine the behaviour of high-velocity features (HVFs) in SN Ia spectra. We take advantage of the fact that Si II 6355 is free of HVFs at maximum light in all SNe Ia, allowing us to quantify the strength of HVFs by comparing the structure of these two lines. We find that the average HVF strength increases with decreasing light-curve decline rate, and rapidly declining SNe Ia (dm_15(B) >= 1.4 mag) show no HVFs in their maximum-light spectra. Comparison of HVF strength to the light-curve colour of the SNe Ia in our sample shows no evidence of correlation. We find a correlation of HVF strength with the velocity of Si II 6355 at maximum light (v_Si), such that SNe Ia with lower v_Si have stronger HVFs, while those SNe Ia firmly in the "high-velocity" (i.e., v_Si >= 12,000 km/s) subclass exhibit no HVFs in their maximum-light spectra. While v_Si and dm_15(B) show no correlation in the full sample of SNe Ia, we find a significant correlation between these quantities in the subset of SNe Ia having weak HVFs. In general, we find that slowly declining (low dm_15(B)) SNe Ia, which are more luminous and more energetic than average SNe Ia, tend to produce either high photospheric ejecta velocities (i.e., high v_Si) or strong HVFs at maximum light, but not both. Finally, we examine the evolution of HVF strength for a sample of SNe Ia having extensive pre-maximum spectroscopic coverage and find significant diversity of the pre-maximum HVF behaviour.
description: Version accepted by MNRAS
Performance Prediction for Multi-hop Question Answering
Creators: Samadi, Mohammadreza
Publisher: name: University of Alberta Library
Year: 2023

In this thesis, we study the problem of performance prediction for open-domain multi-hop Question Answering (QA), where the task is to estimate the difficulty of evaluating a multi-hop question over a corpus. Despite the extensive research on predicting the performance of ad-hoc and QA retrieval models, there has been a lack of study on the estimation of the difficulty of multi-hop questions. The problem is challenging due to the multi-step nature of the retrieval process, potential dependency of the steps and the reasoning involved. To tackle this challenge, we propose multHP, a novel pre-retrieval method for predicting the performance of open-domain multi-hop questions. Our evaluation on one of the largest multi-hop QA dataset shows that the proposed model is a strong predictor of the performance of several modern QA systems, outperforming traditional single-hop query performance prediction methods. Furthermore, given the dynamic nature of information retrieval in multi-hop question answering, post-retrieval methods offer a more accurate means of measuring the difficulty of multi-hop questions compared to pre-retrieval methods. Thus, we present a post-retrieval method tailored for multi-hop question answering, highlighting the limitations of other methods proposed in the ad-hoc retrieval domain that may not be applicable in this specific context. We demonstrate that our approach can be effectively used to optimize the parameters of the systems, such as the number of documents to be retrieved, resulting in improved overall retrieval performance.
Sonnenfleckenzeichnung Nr. 251.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 26.11.2015, 08:30, erstellt von Marco Cagnotti
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 2015

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 1.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Electronic properties of Co$_{2}$FeSi investigated by x-ray magnetic linear dichroism
Creators: name: Emmel, Mirko
name: Alfonsov, Alexey
name: Legut, Dominik
name: Kehlberger, Andreas
name: Vilanova, Enrique
name: Krug, Ingo P.
name: Gottlob, Daniel M.
name: Belesi, Marilena
name: Büchner, Bernd
name: Kläui, Mathias
name: Oppeneer, Peter M.
name: Wurmehl, Sabine
name: Elmers, Hans-Joachim
name: Jakob, Gerhard
Publisher: name: arXiv
Year: 2013
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We present experimental XMLD spectra measured on epitaxial (001)-oriented thin Co$_{2}$FeSi films, which are rich in features and depend sensitively on the degree of atomic order and interdiffusion from capping layers. Al- and Cr-capped films with different degrees of atomic order were prepared by DC magnetron sputtering by varying the deposition temperatures. The local structural properties of the film samples were additionally investigated by nuclear magnetic resonance (NMR) measurements. The XMLD spectra of the different samples show clear and uniform trends at the $L_{3,2}$ edges. The Al-capped samples show similar behavior as previous measured XMLD spectra of Co$_2$FeSi$_{0.6}$Al$_{0.4}$. Thus, we assume that during deposition Al atoms are being implanted into the subsurface of Co$_{2}$FeSi. Such an interdiffusion is not observed for the corresponding Cr-capped films, which makes Cr the material of choice for capping Co$_{2}$FeSi films. We report stronger XMLD intensities at the $L_{3,2}$ Co and Fe egdes for films with a higher saturation magnetization. Additionally, we compare the spectra with \textit{ab initio} predictions and obtain a reasonably good agreement. Furthermore, we were able to detect an XMCD signal at the Si $L$-edge, indicating the presence of a magnetic moment at the Si atoms.
Sonnenfleckenzeichnung Nr. 246.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 21.11.2015, 11:00, erstellt von Andrea Manna
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 2015

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 3.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Student Experiences of Extrinsic and Intrinsic Motivation During Assessment
Creators: Schatz, Talia
Publisher: name: University of Alberta Library
Year: 2023

Often, one may think of assessments, assignments, and tests as purely extrinsic

motivators and that students have no intrinsic interest or drive to engage with them. However, there may be instances where students are intrinsically motivated by assessment. It is important to illuminate the various factors associated with both extrinsic as well as intrinsic motivation during the assessment process in order to understand student experiences and to support intrinsic motivation. As well, it is essential to understand how students are intrinsically and extrinsically motivated by assessment, because both types of motivation have been shown to result in differing outcomes in learning and achievement. For example, students that experience intrinsic motivation learn better, experience higher enjoyment, and have better psychological health (Niemiec & Ryan, 2009; Wang et al., 2019), while extrinsic motivation is associated with lesser interest, value, and effort toward tasks (Ryan & Connell, 1989).

This study aimed to investigate students’ experiences of extrinsic and intrinsic motivation during assessment. Students were asked to describe their experiences of extrinsic and intrinsic motivation during assessment through written responses to two prompts. A qualitative descriptive research design was used to examine students’ responses. As there are few studies that examine the relationship between extrinsic and intrinsic motivation and assessment, this study will contribute to filling the gap in the research literature. The results of this study will have implications for educators seeking to improve assessment practices, increase students’ intrinsic motivation, and mitigate the negative effects of extrinsic motivation.
Sonnenfleckenzeichnung Nr. 148.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 15.07.2015, 08:00, erstellt von Sergio Cortesi
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 2015

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 3.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Singularity resolution by lattice shifts in discretised quantum mechanics
Creators: name: Louko, Jorma
name: Philpott, Samuel P.
name: Waller, Matthew D.
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We investigate the robustness of singularity avoidance mechanisms in nonrelativistic quantum mechanics on the discretised real line when lattice points are allowed to approach a singularity of the classical potential. We consider the attractive Coulomb potential and the attractive scale invariant potential, on an equispaced parity-noninvariant lattice and on a non-equispaced parity-invariant lattice, and we examine the energy eigenvalues by a combination of analytic and numerical techniques. While the lowest one or two eigenvalues descend to negative infinity in the singular limit, we find that the higher eigenvalues remain finite and form degenerate pairs, close to the eigenvalues of a theory in which a lattice point at the singularity is regularised either by Thiemann's loop quantum gravity singularity avoidance prescription or by a restriction to the odd parity sector. The approach to degeneracy can be reproduced from a nonsingular discretised half-line quantum theory by tuning a boundary condition parameter. The results show that Thiemann's singularity avoidance prescription and the discretised half-line boundary condition reproduce quantitatively correct features of the singular limit spectrum apart from the lowest few eigenvalues.
description: 16 pages, 2 figures. v2: presentational clarifications. Published version
Sonnenfleckenzeichnung Nr. 190.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 06.09.2015, 07:45, erstellt von Andrea Manna
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 2015

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 3.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Measurement of the top quark charge in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
Creators: name: The ATLAS Collaboration
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: A measurement of the top quark electric charge is carried out in the ATLAS experiment at the Large Hadron Collider using 2.05 fb-1 of data at a centre-of-mass energy of 7 TeV. In units of the elementary electric charge, the top quark charge is determined to be 0.64 +- 0.02 (stat.) +- 0.08 (syst.) from the charges of the top quark decay products in single lepton ttbar candidate events. This excludes models that propose a heavy quark of electric charge --4/3, instead of the Standard Model top quark, with a significance of more than 8 sigma.
description: 26 pages plus author list (45 pages total), 8 figures, 7 tables, submitted to JHEP, All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/TOPQ-2011-13/
Sonnenfleckenzeichnung Nr. 247.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 22.11.2015, 10:45, erstellt von Andrea Manna
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 2015

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 2.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Persistent spin excitations in doped antiferromagnets revealed by resonant inelastic light scattering
Creators: name: Jia, C. J.
name: Nowadnick, E. A.
name: Wohlfeld, K.
name: Kung, Y. F.
name: Chen, C. -C.
name: Johnston, S.
name: Tohyama, T.
name: Moritz, B.
name: Devereaux, T. P.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: How coherent quasiparticles emerge by doping quantum antiferromagnets is a key question in correlated electron systems, whose resolution is needed to elucidate the phase diagram of copper oxides. Recent resonant inelastic X-ray scattering (RIXS) experiments in hole-doped cuprates have purported to measure high-energy collective spin excitations that persist well into the overdoped regime and bear a striking resemblance to those found in the parent compound, challenging the perception that spin excitations should weaken with doping and have a diminishing effect on superconductivity. Here we show that RIXS at the Cu L3-edge indeed provides access to the spin dynamical structure factor once one considers the full influence of light polarization. Further we demonstrate that high-energy spin excitations do not correlate with the doping dependence of Tc, while low-energy excitations depend sensitively on doping and show ferromagnetic correlations. This suggests that high-energy spin excitations are marginal to pairing in cuprate superconductors.
description: main text with 4 figures; supplementary material with 7 figures
The Development and Evaluation of a Frequently-Asked Question (FAQ) Answering Chatbot for an Online Mental Wellness Program for People with Chronic Disease
Creators: Sadasivan, Chikku
Publisher: name: University of Alberta Library
Year: 2023

Introduction: Chatbots are computer programs that interact with humans through natural language conversations. Chatbots are on the rise due to numerous benefits like convenience, 24/7, personalized support, and they show promise in healthcare to support people living with chronic diseases. While chatbots, like other digital health interventions, are promising tools for chronic disease management, they also face challenges such as limited user adoption and low engagement. One way to address these challenges is to involve patients in development.

Objectives: The purpose of these studies was to report the non-technical (e.g. non-software development related) approaches for chatbot creation while examining patient engagement in these approaches and to develop the FAQ chatbot and evaluate its acceptability, usability, and user engagement through a multi-method approach.

Methods: In Chapter 3, our team conducted a scoping review following the framework proposed by Arksey and O’Malley. Nine electronic databases were searched in July 2022. Studies were selected based on our inclusion/exclusion criteria. Data were then extracted, and patient involvement was assessed. In Chapter 4, a FAQ-answering chatbot (“Liv”) was developed from May 2022 to February 2023 and evaluated through a multi-phased, multi-method design. Liv was then deployed on an online mental wellness program and evaluated for acceptability, usability, and user engagement.

Results: In Chapter 3, 16 studies were included in the review. We report several approaches to chatbot development, assess patient involvement where possible, and reveal the limited detail available on reporting patient involvement in the chatbot implementation process. In Chapter 4, Liv was deployed for 120 days, and there were 259 conversations with Liv, with 175 instances of active engagement (back-and-forth user-chatbot interaction). Engagement was highest during the first 30 days of deployment. The chatbot had a resolution rate of 33%. Liv’s usability was evaluated with an overall score of 50.8 (below average), with successes in specific areas, including its navigation and ease of use. Findings from qualitative interviews included comments on Liv’s personality, the convenience of knowing the chatbot would escalate, and experiences with Liv and her improvement over time.

Conclusion: FAQ chatbots may be an engaging way to provide patient support in online mental wellness programming. Including patients in development may improve chatbot acceptability, usability, and user engagement. Future work that prioritizes patient engagement in the development and builds upon conversation log data to create a more advanced bot is warranted.
Sonnenfleckenzeichnung Nr. 6.
Zeichnung von Flecken und Fackelflächen zur Ermittlung der Sonnenaktivität am 06.01.2015, 11:30, erstellt von Andrea Manna
Creators: name: Observatorium Specola Solare Ticinese Locarno (1957 bis 1980 Teil der Eidgenössischen Sternwarte der ETH Zürich)
Publisher: name: [s.n.]
Year: 2015

description: Bleistiftzeichnung mit schwarzer Farbe und Bleistift, erstellt als Projektionsbildzeichnung für die Beobachtungen in Locarno-Monti auf einem eigenen Vordruck. Instrument: Zeiss-Coudé-Refraktor mit 15 cm Öffnung und 225 cm Brennweite. Bildqualität (SIDC): 3.
Die Beobachtungen zu Einzelflecken und zu Sonnenfleckengruppen wurden auf dem Vordruck eingetragen. Zusätzlich sind zuhanden der späteren statistischen Verarbeitung die Angaben für die Bestimmung der Fleckenrelativzahl notiert.
Beobachtungstätigkeit unter eigenständiger Leitung (Associazione Specola Solare Ticinese ASST)
Fermionic Projected Entangled Pair States at Finite Temperature
Creators: name: Czarnik, Piotr
name: Dziarmaga, Jacek
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Superconductivity (cond-mat.supr-con)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: An algorithm for imaginary time evolution of a fermionic projected entangled pair state (PEPS) with ancillas from infinite temperature down to a finite temperature state is presented. As a benchmark application, it is applied to spinless fermions hopping on a square lattice subject to $p$-wave pairing interactions. With a tiny bias it allows to evolve the system across a high-temperature continuous symmetry-breaking phase transition.
description: 7 pages, 11 figures; new results on a high-Tc phase transition were added
Diffusion and Coulomb separation of ions in dense matter
Creators: name: Beznogov, M. V.
name: Yakovlev, D. G.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We analyze diffusion equations in strongly coupled Coulomb mixtures of ions in dense stellar matter. Strong coupling of ions in the presence of gravitational forces and electric fields (induced by plasma polarization in the presence of gravity) produces a specific diffusion current which can separate ions with the same A/Z (mass to charge number) ratios but different Z. This Coulomb separation of ions can be important for the evolution of white dwarfs and neutron stars.
description: 5 pages, 2 figures; slightly updated with respect to version 1
Environmental Chamber and Fixture Design for Hydrodynamic Thermal Aging of Coupons and Fibers
Creators: Wong, Jerome C.L.
Publisher: name: University of Alberta Library
Year: 2023

Accelerated aging of test specimens has always been the staple method for determining long term compatibility for any material in a given range of process conditions. The application of accelerated aging is to simulate real time conditions in an accelerated manner utilizing more severe conditions while maintaining consistency between the test specimens to minimize any unintended deviations of these parameters from target conditions. This thesis explores various designs for holding tensile test coupons and loose fibers along with their advantages and disadvantages. A brief discussion of the fiber aging fixtures are explored and compared. The tensile test coupon aging setup is investigated and described in detail with the use of temperature logging, visual dye tests, and computational fluid dynamics to quantify its effectiveness at maintaining fluid homogeneity and the aging conditions. Initial trials of both the fiber fixtures and tensile test coupon aging setups are discussed along with their initial issues and solutions. As the experiments are ongoing as of writing this thesis, the finalized results are not available for discussion and are also not in the scope of this thesis.
A Generalized Weil Representation for the finite split orthogonal group $O_q(2n,2n)$, $q$ odd greater than $3$
Creators: name: Gajardo, Andrea Vera
Publisher: name: arXiv
Year: 2013
Subjects: subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: 20C33

description: We construct via generators and relations a generalized Weil representation for the split orthogonal group $\ot_q(2n,2n)$ over a finite field of $q$ elements. Besides, we give an initial decomposition of the representation found. We also show that the constructed representation is equal to the restriction of the Weil representation to $\ot_q(2n,2n)$ for the reductive dual pair $(\Sp_2(\mathbb{F}_q),\ot_q(2n,2n))$ and that the initial decomposition is the same as the decomposition with respect to the action of $\Sp_2(\mathbb{F}_q)$.
title: Third-Eye
Creators: name: Fassler, Aaron
Publisher: name: Utah State University
Year: 2019

description: The Third-Eye Device is a peripheral device compatible with any firearm equipped with the Picatinny rail system. Its system of a camera attached to the weapon which connects to an eyepiece allows the user to aim the weapon without aiming down the sights. This device is potentially crucial to those who regularly engage in close-quarters combat such as police and military specialists, whose ability to quickly and accurately clear rooms during operations is critical to their safety and the safety of others. The student team was tasked with improving the device, primarily in its survivability in dusty and wet environments, its resistance to impact, and its accuracy at the expected ranges of operation. The impact resistance was to be tested against military standards for dropping. The waterproofing and dustproofing was to be tested against international Ingress Protection ratings. To that end, the student team redesigned the exoskeletons of both the transmitter and receiver to be watertight and impact-resistant. They were also designed to fit a new camera system, updated circuit boards, and an improved battery. Also included in the update were a variety of usability updates, including a side rail on the attachment for a flashlight or laser sight, simplified power, channel switching, and recording buttons, an unobstructive helmet mount, and power and channel indicators. The team created a prototype of the exoskeletons. Although only limited physical testing of the device was possible, the team concluded the device would be sufficient to meet the key requirements and exceeded expectations in the adding of new features.
Étale contractible varieties in positive characteristic
Creators: name: Holschbach, Armin
name: Schmidt, Johannes
name: Stix, Jakob
Publisher: name: arXiv
Year: 2013
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14F35

description: Unlike in characteristic 0, there are no non-trivial smooth varieties over an algebraically closed field k of characteristic p>0 that are contractible in the sense of etale homotopy theory.
description: 6 pages, accepted for publication in Algebra & Number Theory
Squeezing light with Majorana fermions
Creators: name: Cottet, Audrey
name: Kontos, Takis
name: Douçot, Benoit
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Coupling a semiconducting nanowire to a microwave cavity provides a powerfull means to assess the presence or absence of isolated Majorana fermions in the nanowire. These exotic bound states can cause a significant cavity frequency shift but also a strong cavity nonlinearity leading for instance to light squeezing. The dependence of these effects on the nanowire gate voltages gives direct signatures of the unique properties of Majorana fermions, such as their self-adjoint character and their exponential confinement.
description: long version: 11 pages, 5 figures
Baumslag-Solitar groups, relative profinite completions and measure equivalence rigidity
Creators: name: Houdayer, Cyril
name: Raum, Sven
Publisher: name: arXiv
Year: 2013
Subjects: subject: Group Theory (math.GR)
subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 20E06, 20E08, 22D05, 37A20

description: We introduce an algebraic invariant for aperiodic inclusions of probability measure preserving equivalence relations. We use this invariant to prove that every stable orbit equivalence between free pmp actions of direct products of non-amenable Baumslag-Solitar groups whose canonical subgroup acts aperiodically forces the number of factors of the products to be the same and the factors to be isomorphic after permutation. This generalises some of the results obtained by Kida and moreover provides new measure equivalence rigidity phenomena for Baumslag-Solitar groups. We also obtain a complete classification of direct products of relative profinite completions of Baumslag-Solitar groups, continuing recent work of Elder and Willis.
description: 23 pages
Finite Difference Weighted Essentially Non-Oscillatory Schemes with Constrained Transport for Ideal Magnetohydrodynamics
Creators: name: Christlieb, Andrew J.
name: Rossmanith, James A.
name: Tang, Qi
Publisher: name: arXiv
Year: 2013
Subjects: subject: Numerical Analysis (math.NA)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 35L65, 65M06, 65M20, 76W05

description: In this work we develop a class of high-order finite difference weighted essentially non-oscillatory (FD-WENO) schemes for solving the ideal magnetohydrodynamic (MHD) equations in 2D and 3D. The philosophy of this work is to use efficient high-order WENO spatial discretizations with high-order strong stability-preserving Runge-Kutta (SSP-RK) time-stepping schemes. Numerical results have shown that with such methods we are able to resolve solution structures that are only visible at much higher grid resolutions with lower-order schemes. The key challenge in applying such methods to ideal MHD is to control divergence errors in the magnetic field. We achieve this by augmenting the base scheme with a novel high-order constrained transport approach that updates the magnetic vector potential. The predicted magnetic field from the base scheme is replaced by a divergence-free magnetic field that is obtained from the curl of this magnetic potential. The non-conservative weakly hyperbolic system that the magnetic vector potential satisfies is solved using a version of FD-WENO developed for Hamilton-Jacobi equations. The resulting numerical method is endowed with several important properties: (1) all quantities, including all components of the magnetic field and magnetic potential, are treated as point values on the same mesh (i.e., there is no mesh staggering); (2) both the spatial and temporal orders of accuracy are fourth-order; (3) no spatial integration or multidimensional reconstructions are needed in any step; and (4) special limiters in the magnetic vector potential update are used to control unphysical oscillations in the magnetic field. Several 2D and 3D numerical examples are presented to verify the order of accuracy on smooth test problems and to show high-resolution on test problems that involve shocks.
description: 39 pages, 9 figures, 4 tables
Epitaxial Growth of VO$_{2}$ by Periodic Annealing
Creators: name: Tashman, J. W.
name: Lee, J. H.
name: Paik, H.
name: Moyer, J. A.
name: Misra, R.
name: Mundy, J. A.
name: Spila, T.
name: Merz, T. A.
name: Schubert, J.
name: Muller, D. A.
name: Schiffer, P.
name: Schlom, D. G.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We report the growth of ultrathin VO$_{2}$ films on rutile TiO$_{2}$ (001) substrates via reactive molecular-beam epitaxy. The films were formed by the cyclical deposition of amorphous vanadium and its subsequent oxidation and transformation to VO$_{2}$ via solid-phase epitaxy. Significant metal-insulator transitions were observed in films as thin as 2.3 nm, where a resistance change ΔR/R of 25 was measured. Low angle annular dark field scanning transmission electron microscopy was used in conjunction with electron energy loss spectroscopy to study the film/substrate interface and revealed the vanadium to be tetravalent and the titanium interdiffusion to be limited to 1.6 nm.
description: 25 pages, 6 figures
Introductory lectures to large-N QCD phenomenology and lattice results
Creators: name: Lucini, Biagio
name: Panero, Marco
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: An elementary, pedagogical introduction to the large-N limit of QCD and to its phenomenological implications is presented, and a survey of lattice results in the 't Hooft limit is briefly discussed.
description: 60 pages, 25 eps figures, prepared for submission to Progress in Particle and Nuclear Physics; v2: minor text revision, added references: version published in the journal
Self-energy and vertex functions from hybridization expansion continuous-time quantum Monte Carlo for impurity models with retarded interaction
Creators: name: Hafermann, Hartmut
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Optimized measurements for the susceptibility, self-energy, as well as three-leg and four-leg vertex functions are introduced for the continuous-time hybridization expansion quantum Monte Carlo solver for the impurity model in presence of a retarded interaction. The self-energy and vertex functions are computed from impurity averages which involve time integrals over the retarded interaction. They can be evaluated efficiently within the segment representation. These quantities are computed within dynamical mean-field theory in presence of plasmonic screening. In the antiadiabatic regime, the self-energy is strongly renormalized but retains features of the low energy scale set by the screened interaction. An explicit expression for its high-frequency behavior is provided. Across the screening-driven and interaction-driven metal-insulator transitions, the vertex functions are found to exhibit similar structural changes, which are hence identified as generic features of the Mott transition.
description: Published version; 20 pages, 17 figures
Beauty is more attractive: Particle Production and Moduli trapping with Higher Dimensional Interaction
Creators: name: Enomoto, Seishi
name: Iida, Satoshi
name: Maekawa, Nobuhiro
name: Matsuda, Tomohiro
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study quantum effects on moduli dynamics arising from particle production near the enhanced symmetry point (ESP). We focus on non-renormalizable couplings between the moduli field and the field that becomes light at the ESP. Considering higher dimensional interaction, we find that particle production is significant in a large area, which is even larger than the area that is expected from a renormalizable interaction. It is possible to find this possibility from a trivial adiabatic condition; however the quantitative estimation of particle production and trapping of the field in motion are far from trivial. In this paper we study particle production and trapping in detail, using both the analytical and numerical calculations, to find a clear and intuitive result that supports trapping in a vast variety of theories. Our study shows that trapping driven by a non-renormalizable interaction is possible. This possibility has not been considered in previous works. Some phenomenological models of particle physics will be mentioned to complement discussion.
description: 19 pages, 6 figures, 1 table
Improvement of Masonry Construction Site Conditions Using Lean Principles
Creators: Keyrouz, Karl
Publisher: name: University of Alberta Library
Year: 2023

Construction site conditions are suboptimal and current practices generate a lot of waste in all its forms (material, equipment, resources, etc.), hindering the true potential of productivity and value generation on construction sites. Lean Construction research studies oriented toward improving site conditions are available, focusing on specific aspects of waste. Nevertheless, there is still a gap in improving construction flow research, both at the micro and macro levels.

This study presents a framework to analyze and optimize construction site conditions. The concept developed in the framework is rooted in Lean Thinking and Theory. A case study of the masonry construction process is performed to test and validate the framework. The different types of walls using masonry construction as a construction method were compiled and presented.

Lean tools were used in this case study, namely Value Stream Mapping and Simulation Modelling, to study the performance of the current masonry construction practices on construction sites. Bottlenecks in the current process were identified, and a base-case scenario was proposed with potential solutions; extracted and analyzed metrics included: construction lead time, daily productivity, and station utilization. Subsequently, the use of modular construction, interlocking masonry blocks and a robot platform were proposed as solutions for improving construction site conditions. These three systems were studied and analyzed using Simulation Modelling compared to the traditional masonry construction process. Each solution was shown to partially remediate some problems encountered in traditional masonry construction practices. Modular construction improved scheduling issues, whereas the interlocking blocks could solve the problematic use of mortar. The robot platform and arm would remediate the problems of waste related to material handling on site.

In conclusion, this study analyzed the construction systems, both at the micro and macro levels. Simulation Modelling showed that combining three interventions: modular construction, interlocking blocks, and a robotic platform, could substantially decrease waste while increasing generated value. This case study sets the ground for the future adoption of automated/robotic technology in Lean Construction Engineering.
Cross Ratios of Quadrilateral Linkages
Creators: name: Khimshiashvili, Giorgi
name: Siersma, Dirk
Publisher: name: arXiv
Year: 2013
Subjects: subject: Metric Geometry (math.MG)
subject: FOS: Mathematics

description: We discuss the cross-ratio map of planar quadrilateral linkages, also in the case when one of the links is telescopic. Most of our results are valid for a planar quadrilateral linkage with generic lengths of the sides. In particular, we describe the image of cross-ratio map for quadrilateral linkage and planar robot 3-arm.
description: 12 pages,9 figures. March 2014: Proofs are added, typo's corrected; March 2015: Typo's corrected
Generating all finite modular lattices of a given size
Creators: name: Jipsen, Peter
name: Lawless, Nathan
Publisher: name: arXiv
Year: 2013
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: Modular lattices, introduced by R. Dedekind, are an important subvariety of lattices that includes all distributive lattices. Heitzig and Reinhold developed an algorithm to enumerate, up to isomorphism, all finite lattices up to size 18. Here we adapt and improve this algorithm to construct and count modular lattices up to size 24, semimodular lattices up to size 22, and lattices of size 19. We also show that $2^{n-3}$ is a lower bound for the number of nonisomorphic modular lattices of size $n$.
description: Preprint, 12 pages, 2 figures, 1 table
G-Reconstruction and the Hopf Equivariantization Theorem
Creators: Riesen, Andrew
Publisher: name: University of Alberta Library
Year: 2023

$G$-structures on fusion categories have been shown to be an important tool to understand orbifolds of vertex operator algebras \cite{Kirillov}\cite{Gcrossedmuger}\cite{Orbifold_Paper}. We continue to develop this idea by generalizing Eilenberg-Maclane's notion of an Abelian $3$-cocycle  to describe $G$-structures on fusion categories as $G$-(crossed, ribbon) Abelian $3$-cocycles on an algebra $H$. In particular, we show that a $G$-(crossed, ribbon) Abelian $3$-cocycle on $H$ will induce a $G$-(crossed braided, ribbon) tensor structure on its category of modules $\mathrm{Mod}(H)$. We then prove that every  $G$-(crossed braided, ribbon) fusion category $\mathcal{C}$ will be equivalent to the category of modules of some finite dimensional algebra $H$ with $G$-structure induced from a $G$-(crossed, ribbon) Abelian $3$-cocycle. We call this $G$-reconstruction.

Lastly, we prove that a $G$-ribbon Abelian $3$-cocycle $\Gamma$ on $H$ allows us to describe the equivariantization $(\Mod(H))^G$ as the category of modules of a ribbon (weak) quasi Hopf algebra $H\#_{\Gamma}\mathbb{C}[G]$. We call this the Hopf equivariantization theorem.

By $G$-reconstruction this shows that if $\mathcal{V}$ is a strongly rational vertex operator algebra where $G$ acts faithfully on $\mathcal{V}$ such that $\mathcal{V}^G$ is also strongly rational, then there is an equivalence of modular fusion categories:

\begin{equation}

\mathrm{Mod}\ \mathcal{V}^G \cong \mathrm{Mod}(H\#_{\Gamma}\mathbb{C}[G])

\end{equation}

for some finite dimensional algebra $H$ with a $G$-ribbon Abelian $3$-cocycle $\Gamma$. This provides a proof of the Dijkgraaf-Witten conjecture, and generalizes it as far as possible in the semi-simple setting.
Non-$γ_{5}$hermiticity minimal doubling fermion
Creators: name: Kamata, Syo
name: Tanaka, Hidekazu
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We formulate new two dimensional fermions breaking $γ_{5}$hermiticity, based on the minimal doubling fermion. We investigate their properties: (I) Symmetries, (II) eigenvalue distributions, and (III)the number of poles. As a simple application of the fermions, the Gross-Neveu model in two dimensions is studied using the fermion. We obtain the parity broken phase diagram called Aoki phase and the chiral broken phase diagram of the model with an imaginary chemical potential.
description: 7 pages, 15 figures, presented at the 31st International Symposium on Lattice Field Theory (Lattice 2013), 29 July - 3 August 2013, Mainz, Germany
The Spectrum of Light States in Large N Minimal Models
Creators: name: Gaberdiel, Matthias R.
name: Gopakumar, Rajesh
name: Rangamani, Mukund
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: $W_{N,k}$ minimal models possess an interesting class of `light' primaries which control much of the low energy density of states in the large $N$ 't Hooft limit. In this paper we conduct a detailed exploration of their distribution using a combination of numerical and analytical techniques. We also make some observations about the density of states of the full CFT. Our results appear to support the contention that there is no finite temperature analogue of the Hawking-Page transition in these systems.
description: 40 pages, 8 figures. v2: typos fixed. published version
Latest Progress on the QUBIC Instrument
Creators: name: Ghribi, A.
name: Aumont, J.
name: Battistelli, E. S.
name: Bau, A.
name: Bergé, L.
name: Bernard, J-Ph.
name: Bersanelli, M.
name: Bigot-Sazy, M-A.
name: Bordier, G.
name: Bunn, E. T.
name: Cavaliere, F.
name: Chanial, P.
name: Coppolecchia, A.
name: Decourcelle, T.
name: De Bernardis, P.
name: De Petris, M.
name: Drilien, A-A.
name: Dumoulin, L.
name: Falvella, M. C.
name: Gault, A.
name: Gervasi, M.
name: Giard, M.
name: Gradziel, M.
name: Grandsire, L.
name: Gayer, D.
name: Hamilton, J-Ch.
name: Haynes, V.
name: Giraud-Héraud, Y.
name: Holtzer, N.
name: Kaplan, J.
name: Korotkov, A.
name: Lande, J.
name: Lowitz, A.
name: Maffei, B.
name: Marnieros, S.
name: Martino, J.
name: Masi, S.
name: Mennella, A.
name: Montier, L.
name: Murphy, A.
name: Ng, M. W.
name: Olivieri, E.
name: Pajot, F.
name: Passerini, A.
name: Piacentini, F.
name: Piat, M.
name: Piccirillo, L.
name: Pisano, G.
name: Prêle, D.
name: Rambaud, D.
name: Rigaut, O.
name: Rosset, C.
name: Salatino, M.
name: Schillaci, A.
name: Scully, S.
name: O'Sullivan, C.
name: Tartari, A.
name: Timbie, P.
name: Tucker, G.
name: Vibert, L.
name: Voisin, F.
name: Watson, B.
name: Zannoni, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: QUBIC is a unique instrument that crosses the barriers between classical imaging architectures and interferometry taking advantage from both for high sensitivity and systematics mitigation. The scientific target is the detection of the primordial gravitational waves imprint on the Cosmic Microwave Background which are the proof of inflation, holy grail of modern cosmology. In this paper, we show the latest advances in the development of the architecture and the sub-systems of the first module of this instrument to be deployed in Dome Charlie Concordia base - Antarctica in 2015.
description: 6 pages, 2 figures, conference LTD15
First determination of $f_+(0) |V_{us}|$ from a combined analysis of $τ\to Kπν_τ$ decay and $πK$ scattering with constraints from $K_{\ell3}$ decays
Creators: name: Bernard, Veronique
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We perform a combined analysis of $τ\to Kπν_τ$ decay and $πK$ scattering with constraints from $K_{\ell3}$ data using a $N/D$ approach that fulfills requirements from unitarity and analyticity. We obtain a good fit of the $I=1/2$ $πK$ amplitude in the $P$ wave using the LASS data above the elastic region while in this region data are generated via Monte Carlo using the FOCUS results based on $D_{\ell 4}$ decay. The spectrum and branching ratio of $τ\to Kπν_τ$ constrained by $K_{\ell3}$ decays are also well reproduced leading to $f_+(0) |V_{us}|= 0.2163 \pm 0.0014 $. Furthermore, we obtain the slope of the vector form factor $λ_+=(25.56 \pm 0.40) \times 10^{-3} $ while the value of the scalar form factor at the Callan-Treiman point is $\ln C=0.2062 \pm 0.0089$. Given the experimental precision our results are compatible with the Standard model.
description: 30 pages, 7 figures, Updated numerics and discussion slightly extended. Published version
Measuring proteomic changes associated with viral infections and neurodegenerative diseases using mass spectrometry
Creators: Moussa, Eman W
Publisher: name: University of Alberta Library
Year: 2023

Viral infection and the resultant cellular stress can trigger significant changes to the cellular host proteome. Viral proteases essential to viral replication have been shown to cleave human host protein substrates as a mechanism of immune response evasion. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of COVID-19 and the resulting COVID-19 pandemic. The widespread impact of this virus illustrates the need to better understand its biology and the role of its viral proteases. We used mass spectrometry to characterize the host protein substrates of the SARS-CoV-2 viral proteases that play a role in its evasion of the immune response. We show that bromodomain-containing protein 2 (BRD2) and splicing factor proline- and glutamine-rich (SFPQ) are potential substrates of the SARS-CoV-2 main (Mpro) and papain-like viral proteases (PLpro), respectively. The identification of these human host protein substrates aids in our understanding of the biology of viral infection and how the SARS-CoV-2 virus may evade the host's immune response. Our results may also provide a foundation of knowledge that can be used to guide studies of potential future coronaviruses, similar to how SARS-CoV-1 studies have guided SARS-CoV-2 studies.

Additionally, we highlight the use of mass spectrometry as a powerful tool to study proteomic changes in neurodegenerative diseases, viral infections in the cells of the central nervous system, and protein mistranslation. Our investigation into the role of gasdermin-D in multiple sclerosis, using a cuprizone mouse model, demonstrates changes in protein abundance with disease suggesting increased astrocyte and microglia activity. Furthermore, infection of human astrocytes with monkeypox virus (MPXV) and vaccinia virus (VACV) demonstrates the greater impact of MPXV infection on mitochondrial protein functions, compared to VACV infection. Lastly, we present alternative approaches for the identification of protein mistranslation due to oxidative stress and the disrupted function of the methionyl-tRNA synthetase (MARS). These results highlight the need for bioinformatic and database-driven analysis, in addition to traditional mass spectrometry, for the identification of low abundance mistranslational events.