cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Impact of Semi-continuous and Alternating Microbial Feeding Patterns on Methane Yield from UASB Reactors
Creators: Yuan, Yiyang
Publisher: name: University of Alberta Library
Year: 2023

The anaerobic treatment of wastewater is considered a promising technology for simultaneous organic matter removal and energy recovery. Compared to aerobic digestion, anaerobic digestion conserves energy and is cost-effective in handling high-strength wastewater and wastes. However, the high sensitivity of anaerobic systems to operational conditions such as temperature, pH, mixing conditions and feeding regimes has limited their application. In particular, feeding patterns have been shown to significantly impact the reactor operations, while a flexible feeding regime is commonly needed when treating the unequalized feedstock. To date, our understanding of the impact of bioreactor feeding strategies on anaerobic bioreactor performance is still limited.

The overall objective of this thesis is to evaluate the impact of various feeding strategies on the development of robust microbial communities in bioreactors and the anaerobic bioreactor treatment performance. Three feeding strategies, including continuous, semi-continuous (with starvation-feast cycle), and alternate feeding (with high loading-low loading cycle), were compared in this study to assess anaerobic digestion of synthetic wastewater and methane yields using three continuously operating laboratory-scale up-flow anaerobic sludge blanket (UASB) reactors. Observation of this study revealed that both long and short starvation-feast cycles provided by semi-continuous feeding did not sustain stable anaerobic digestion, whereas alternate feeding with high and low loading cycles promoted microbial community development. With dominant methanogens shifted from Methanosaeta in the continuous reactor to Methanosarcina in semi-continuous feeding reactors, significantly higher methanogenic activities were observed once reactors were recovered. Interestingly, the reactor undergoing the alternate feeding mode

ii

successfully maintained a stable operation and thus the alternate feeding pattern is preferred over semi-continuous feeding when reactor feeding is not continuously and consistently available.
A GMOS/IFU Study of Jellyfish Galaxies in Massive Clusters
Creators: name: Lee, Jeong Hwan
name: Lee, Myung Gyoon
name: Mun, Jae Yeon
name: Cho, Brian S.
name: Kang, Jisu
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Jellyfish galaxies are an intriguing snapshot of galaxies undergoing ram-pressure stripping (RPS) in dense environments, showing spectacular star-forming knots in their disks and tails. We study the ionized gas properties of five jellyfish galaxies in massive clusters with Gemini GMOS/IFU observations: MACSJ0916-JFG1 ($z=0.330$), MACSJ1752-JFG2 ($z=0.353$), A2744-F0083 ($z=0.303$), MACSJ1258-JFG1 ($z=0.342$), and MACSJ1720-JFG1 ($z=0.383$). BPT diagrams show that various mechanisms (star formation, AGN, or mixed effects) are ionizing gas in these galaxies. Radial velocity distributions of ionized gas seem to follow disk rotation of galaxies, with the appearance of a few high-velocity components in the tails as a sign of RPS. Mean gas velocity dispersion is lower than 50 \kms~in most star-forming regions except near AGNs or shock-heated regions, indicating that the ionized gas %in these star-forming regions is dynamically cold. Integrated star formation rates (SFRs) of these galaxies range from $7~{\rm M_{\odot}~{\rm yr^{-1}}}$ to $35~{\rm M_{\odot}~{\rm yr^{-1}}}$ and the tail SFRs are from $0.6~{\rm M_{\odot}~{\rm yr^{-1}}}$ to $16~{\rm M_{\odot}~{\rm yr^{-1}}}$, which are much higher than those of other jellyfish galaxies in the local universe. These high SFR values imply that RPS triggers intense star formation activity in these extreme jellyfish galaxies. The phase-space diagrams demonstrate that the jellyfish galaxies with higher stellar masses and higher host cluster velocity dispersion are likely to have more enhanced star formation activity. The jellyfish galaxies in this study have similar gas kinematics and dynamical states to those in the local universe, but they show a much higher SFR.
description: Accepted for publication in ApJ, 26 pages, 13 figures, 6 tables
An explanatory evo-devo model for the developmental hourglass
Creators: name: Akhshabi, Saamer
name: Sarda, Shrutii
name: Dovrolis, Constantine
name: Yi, Soojin
Publisher: name: arXiv
Year: 2013
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Molecular Networks (q-bio.MN)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: The "developmental hourglass" describes a pattern of increasing morphological divergence towards earlier and later embryonic development, separated by a period of significant conservation across distant species (the "phylotypic stage"). Recent studies have found evidence in support of the hourglass effect at the genomic level. For instance, the phylotypic stage expresses the oldest and most conserved transcriptomes. However, the regulatory mechanism that causes the hourglass pattern remains an open question. Here, we use an evolutionary model of regulatory gene interactions during development to identify the conditions under which the hourglass effect can emerge in a general setting. The model focuses on the hierarchical gene regulatory network that controls the developmental process, and on the evolution of a population under random perturbations in the structure of that network. The model predicts, under fairly general assumptions, the emergence of an hourglass pattern in the structure of a temporal representation of the underlying gene regulatory network. The evolutionary age of the corresponding genes also follows an hourglass pattern, with the oldest genes concentrated at the hourglass waist. The key behind the hourglass effect is that developmental regulators should have an increasingly specific function as development progresses. Analysis of developmental gene expression profiles from Drosophila melanogaster and Arabidopsis thaliana provide consistent results with our theoretical predictions.
Limits on anisotropic inflation from the Planck data
Creators: name: Kim, Jaiseung
name: Komatsu, Eiichiro
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Temperature anisotropy of the cosmic microwave background offers a test of the fundamental symmetry of spacetime during cosmic inflation. Violation of rotational symmetry yields a distinct signature in the power spectrum of primordial fluctuations as $P({\mathbf k})=P_0(k)[1+g_*(\hat{\mathbf k}\cdot\hat{\mathbf E}_{\rm cl})^2]$, where $\hat{\mathbf E}_{\rm cl}$ is a preferred direction in space and $g_*$ is an amplitude. Using the \textit{Planck} 2013 temperature maps, we find no evidence for violation of rotational symmetry, $g_*=0.002\pm 0.016$ (68% CL), once the known effects of asymmetry of the \textit{Planck} beams and Galactic foreground emission are removed.
description: 5 pages, 2 figures. (v2) References added. A typo fixed. (v3) Various confidence levels included, Journal reference added (v4) error of a duplicated pdf file fixed
High Harmonic Generation With Focal Cone Geometry
Creators: Gjevre, John
Publisher: name: University of Alberta Library
Year: 2023

High Harmonic Generation (HHG) is a convenient method of producing coherent extreme ultraviolet (XUV) radiation and is typically produced by focusing a laser onto a gas jet. The total intensity of XUV generated in this method is limited by the ionization threshold of the gas and absorption of XUV radiation in the gas. A new geometry of Focal Cone High Harmonic Generation (FCHHG) is examined. This geometry involves focusing the incoming cone of light through a gas sheet rather than placing a gas jet at laser focus. Such a focusing geometry generates a converging cone of XUV radiation producing a high intensity high harmonic hot spot (HHHS) at focus. Using 100 TW to 1 PW laser pulses, high energy, microjoule to millijoule, coherent XUV pulses should be achievable. An experiment to test this concept was carried out at the Centro de L´aseres Pulsados (CLPU) in Salamanca Spain. For this a gas nozzle was designed to produce a rectangular gas sheet capable of providing a uniform density region over which the laser can interact. A number of diagnostics were used to characterize the XUV beam both

spectrally and spatially. These included an Xray CCD camera and XUV photodiodes to observe the XUV and measure its intensity, spectral measurements using a transmission grating and knife edge diffraction, and divergence measurements using the knife edge and shadowgraphic imaging of perforated meshes. The conversion efficiency as a function of backing pressure, nozzle distance from laser focus and the laser axis, and intensity is also explored.
Dobrushin's ergodicity coefficient for Markov operators on cones
Creators: name: Gaubert, Stephane
name: Qu, Zheng
Publisher: name: arXiv
Year: 2013
Subjects: subject: Functional Analysis (math.FA)
subject: Operator Algebras (math.OA)
subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics

description: We give a characterization of the contraction ratio of bounded linear maps in Banach space with respect to Hopf's oscillation seminorm, which is the infinitesimal distance associated to Hilbert's projective metric, in terms of the extreme points of a certain abstract "simplex". The formula is then applied to abstract Markov operators defined on arbitrary cones, which extend the row stochastic matrices acting on the standard positive cone and the completely positive unital maps acting on the cone of positive semidefinite matrices. When applying our characterization to a stochastic matrix, we recover the formula of Dobrushin's ergodicity coefficient. When applying our result to a completely positive unital map, we therefore obtain a noncommutative version of Dobrushin's ergodicity coefficient, which gives the contraction ratio of the map (representing a quantum channel or a "noncommutative Markov chain") with respect to the diameter of the spectrum. The contraction ratio of the dual operator (Kraus map) with respect to the total variation distance will be shown to be given by the same coefficient. We derive from the noncommutative Dobrushin's ergodicity coefficient an algebraic characterization of the convergence of a noncommutative consensus system or equivalently the ergodicity of a noncommutative Markov chain.
description: An announcement of some of the present results has appeared in the Proceedings of the ECC 2013 conference (Zurich). Further results can be found in the companion arXiv:1302.5226
Answering Count Questions with Structured Answers from Text
Creators: name: Ghosh, Shrestha
name: Razniewski, Simon
name: Weikum, Gerhard
Publisher: name: arXiv
Year: 2022
Subjects: subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: In this work we address the challenging case of answering count queries in web search, such as ``number of songs by John Lennon''. Prior methods merely answer these with a single, and sometimes puzzling number or return a ranked list of text snippets with different numbers. This paper proposes a methodology for answering count queries with inference, contextualization and explanatory evidence. Unlike previous systems, our method infers final answers from multiple observations, supports semantic qualifiers for the counts, and provides evidence by enumerating representative instances. Experiments with a wide variety of queries, including existing benchmark show the benefits of our method, and the influence of specific parameter settings. Our code, data and an interactive system demonstration are publicly available at https://github.com/ghoshs/CoQEx and https://nlcounqer.mpi-inf.mpg.de/.
description: arXiv admin note: text overlap with arXiv:2204.05039
Signal formation and sharing in AC-LGADs using the ALTIROC 0 front-end chip
Creators: name: D'Amen, G.
name: Chen, W.
name: De La Taille, C.
name: Giacomini, G.
name: Marchand, D.
name: Morenas, M.
name: Camacho, C. Munoz
name: Rossi, E.
name: Seguin-Moreau, N.
name: Serin, L.
name: Tricoli, A.
name: Wang, P. -K.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The development of detectors that provide high resolution in four dimensions has attracted wide-spread interest in the scientific community for applications in high-energy physics, nuclear physics, medical imaging, mass spectroscopy as well as quantum information. However, finding a technology capable of fulfilling such aspiration proved to be an arduous task. Among other silicon-based candidates, the Low-Gain Avalanche Diode (LGAD) has already shown excellent timing performances but proved to be unsuitable for fine pixelization. Therefore, the AC-coupled LGAD (AC-LGAD) approach was introduced to provide high resolution in both time and space, making it a promising candidate for future 4D detectors. However, appropriate readout electronics must be developed to match the sensor's fast-time and fine-pitch capabilities. This is currently a major technological challenge. In this paper, we test AC-LGAD prototypes read out by the fast-time ASIC ALTIROC 0, originally developed for the readout of DC-coupled LGADs for the ATLAS experiment at the HL-LHC. Signal generated by either betas from a $^{90}$Sr source or a focused infra-red laser were analyzed. This paper details the first successful readout of an AC-LGAD sensor using a readout chip. This result will pave the way for the design and construction of a new generation of AC-LGAD-based 4D detectors.
Testing Modified Gravity Theories with Numerical Solutions of the External Field Effect in Rotationally Supported Galaxies
Creators: name: Chae, Kyu-Hyun
name: Lelli, Federico
name: Desmond, Harry
name: McGaugh, Stacy S.
name: Schombert, James M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The strong equivalence principle is violated by gravity theories of Milgromian dynamics (MOND) through the action of the external field effect. We test two different Lagrangian theories AQUAL and QUMOND based on their numerical solutions of the external field effect, by comparing two independent estimates of the mean external field strength of the nearby universe: a theory-deduced value from fitting the outer rotation curves of 114 galaxies and an empirical value from the large-scale distribution of cosmic baryons. The AQUAL-deduced external field strength from rotation curves agrees with that from the large-scale cosmic environment, while QUMOND-deduced value is somewhat higher. This suggests that AQUAL is likely to be preferred over QUMOND as an effective non-relativistic limit of a potential relativistic modified gravity theory.
description: 6 pages, 2 figures, 1 table (results revised, conclusions strengthened)
Steady state propulsion of isotropic active colloids along a wall
Creators: name: Desai, Nikhil
name: Michelin, Sebastien
Publisher: name: arXiv
Year: 2022
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Active drops emit/absorb chemical solutes, whose concentration gradients cause interfacial flows driving their own transport and the propulsion of the droplet. Such non-linear coupling enables active drops to achieve directed self-propulsion despite their isotropy, if the ratio of advective-to-diffusive solute transport, i.e. the Peclet number Pe, is larger than a finite critical threshold. In most experimental situations, active drops are non-neutrally buoyant and thus swim along rigid surfaces; yet theoretical descriptions of their non-linear motion focus almost exclusively on unbounded domains to circumvent geometric complexity. To overcome this gap in understanding, we investigate the spontaneous emergence and nonlinear saturation of propulsion of an isotropic phoretic colloid along a rigid wall, to which it is confined by a constant external force (e.g., gravity). This phoretic particle model is considered here as a limiting case for a viscous active drop. We show that, for moderate Pe, the particle motion and associated chemical transport reduce the chemically-induced wall repulsion, thereby causing the particle to swim progressively closer to the wall as Pe increases. Far from hindering self-propulsion, this reduction in the particle-wall separation is accompanied by a wall-induced efficient rearrangement of the solute concentration gradients driving the particle, thus augmenting its swimming speed.
description: to appear in Phys. Rev. Fluids, Special Collection on "Interfacial Active Matter", 11 pages, 7 figures, supplementary information (separate pdf)
Learning Models for Diagnosis and Prognosis from Electrocardiogram Data
Creators: Sun, Weijie
Publisher: name: University of Alberta Library
Year: 2023

The electrocardiogram (ECG) records the electrical activity of a patient’s heart movement. It is one of the standard routine healthcare tests as it is non-invasive and easy to apply. In this thesis, we analyze 2 million ECGs and over 260,000 patients’ health records from the Alberta Health Service, and propose frameworks for learning diagnostic and prognostic models based on supervised learning methods, including ones for survival prediction. First, we learned many models that each use a patient’s ECG to determine if s/he has a specific disease, corresponding to an ICD-10 diagnosis code. Our results show that these diagnosis models can accurately predict numerous health conditions, beyond cardiovascular conditions. Second, we develop ECG diagnosis models for COVID-19 and then use transfer learning to produce models with superior performance. Finally, motivated by the evidence from earlier tasks, we develop binary classification ECG models for predicting all-cause (fixed time) mortality for hospitalized (resp., emergency) patients, and also survival models that produce meaningful survival predictions for each patient. We demonstrate state-of-the-art performance for predicting the time-until-death by using machine learning techniques that first re-express each ECG in latent representations.
title: Das Wissensnetz der Frühen Neuzeit. Von der virtuellen Bibliothek zur virtuellen Enzyklopädie
Creators: name: Gruhl, Reinhard
Publisher: name: University Library Heidelberg
Year: 2013

description: At first glance the project of a Virtual Encyclopedia of the Early Modern Period might appear superfluous: there are a number of printed reference books on the topic available. Among the particularly useful ones we find the “Encyclopedia of the Early Modern World” (Scribner's Sons) and the “Enzyklopädie der Neuzeit” (Metzler). Nevertheless, there is room for innovation. The Heidelberg Project “The Knowledge Map of the Early Modern Period” brought together reference books of the Early Modern Period with the CAMENA text database in a single data base in order to put the data collected to use through a text mining procedure developed by the Institute for Computer Science of Leipzig University. The results are presented in form of a list of contexts for each lemma. They can furthermore be visualized as graphs, giving an intuitive picture of a knowledge map. By including a corpus of ancient texts, epistemic changes in the early modern period can be made visible. This way a Virtual Encyclopaedia that primarily serves the needs of scholars but also a wider audience is being developed.
description: At first glance the project of a Virtual Encyclopedia of the Early Modern Period might appear superfluous: there are a number of printed reference books on the topic available. Among the particularly useful ones we find the “Encyclopedia of the Early Modern World” (Scribner's Sons) and the “Enzyklopädie der Neuzeit” (Metzler). Nevertheless, there is room for innovation. The Heidelberg Project “The Knowledge Map of the Early Modern Period” brought together reference books of the Early Modern Period with the CAMENA text database in a single data base in order to put the data collected to use through a text mining procedure developed by the Institute for Computer Science of Leipzig University. The results are presented in form of a list of contexts for each lemma. They can furthermore be visualized as graphs, giving an intuitive picture of a knowledge map. By including a corpus of ancient texts, epistemic changes in the early modern period can be made visible. This way a Virtual Encyclopaedia that primarily serves the needs of scholars but also a wider audience is being developed.
title: Detailed description of eAQUA search portal
Creators: name: Schubert, Charlotte
Publisher: name: University Library Heidelberg
Year: 2013

description: In order to perform a search for a simple word or a conjunction of multiple words there is in classics currently some established software available (e.g. Diogens by P. Heslin, the Text Search function of TLG-online, Pandora). The search functions of newer text mining methods are going further by offering the potential to show syntagmatic contexts. If two terms are occurring together in at least one local context they are in a relationship that can be denominated as syntagmatic context. The search function of eAQUA is based on this fact. By typing a term in the search mask results of this kind are displayed as a graph visualization
(graphical display of a word net of sentence cooccurrences) and as lists of significant cooccurrences and neighborhood cooccurrences (both ordered by significance). With the help of examples derived from the project work in eAQUA (e.g. rare cooccurrences) shall be elucidated below which new and innovative potentials for the modus operandi of classicists are gained from the use of this search method.
Image color transfer to evoke different emotions based on color combinations
Creators: name: He, Li
name: Qi, Hairong
name: Zaretzki, Russell
Publisher: name: arXiv
Year: 2013
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Graphics (cs.GR)
subject: FOS: Computer and information sciences

description: In this paper, a color transfer framework to evoke different emotions for images based on color combinations is proposed. The purpose of this color transfer is to change the "look and feel" of images, i.e., evoking different emotions. Colors are confirmed as the most attractive factor in images. In addition, various studies in both art and science areas have concluded that other than single color, color combinations are necessary to evoke specific emotions. Therefore, we propose a novel framework to transfer color of images based on color combinations, using a predefined color emotion model. The contribution of this new framework is three-fold. First, users do not need to provide reference images as used in traditional color transfer algorithms. In most situations, users may not have enough aesthetic knowledge or path to choose desired reference images. Second, because of the usage of color combinations instead of single color for emotions, a new color transfer algorithm that does not require an image library is proposed. Third, again because of the usage of color combinations, artifacts that are normally seen in traditional frameworks using single color are avoided. We present encouraging results generated from this new framework and its potential in several possible applications including color transfer of photos and paintings.
description: Signal, Image and Video Processing, September 2014
Gluon-initiated associated production boosts Higgs physics
Creators: name: Englert, Christoph
name: McCullough, Matthew
name: Spannowsky, Michael
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Analyses of boosted Higgs bosons from associated production comprise some of the main search channels for the Higgs boson at the LHC. The gluon-initiated $gg\to hZ$ subprocess has largely been ignored in phenomenological analyses of boosted associated production although this contribution is sizable as the $p_T$ spectrum for this process is maximised in the boosted regime due to the top quark loop threshold. In this paper, we discuss this contribution to boosted $pp\to hZ$ analyses in detail. We find there are previously overlooked modifications of Standard Model Higgs rates at the LHC which depend on the $p_T$ cuts applied and can be significant. There are also important consequences for physics beyond the Standard Model as the $gg\to hZ$ process introduces significant dependence on the magnitude and sign of the Higgs-top quark coupling $c_t$, which is overlooked if it is assumed that associated production depends only on the Higgs-$Z$ boson coupling as $c_V^2$. This new dependence on $c_t$ impacts interpretations of Higgs rates in the contexts of Supersymmetry, Two Higgs Doublet Models, and general scenarios with modified couplings. We suggest that these effects be included in current and future LHC boosted Higgs analyses.
description: Plots added for 7 & 8 TeV. Typo corrected in Eq 10. Matches published version
title: An early Byzantine silver plate with a portrait of St. Theodore
Creators: name: Fourlas, Benjamin
Publisher: name: University Library Heidelberg
Year: 2014

description: Die 1977 erworbene Schale im Römisch-Germanischen Zentralmuseum in Mainz gehört zur Gruppe der mit fünf Kontrollstempeln versehenen frühbyzantinischen Silberobjekte. Die Stempel datieren das Objekt in die
Regierungszeit Kaiser Justinians I. (527-565). Wahrscheinlich entstand die Schale im Zeitraum 527 bis um die Mitte des 6. Jahrhunderts, möglicherweise während der Amtszeit des comes sacrarum largitionum Flavios Strategios (532-539). Der im Mittelmedaillon der Schale dargestellte Heilige kann durch den spezifischen Kopftypus als Theodor Tiron identifiziert werden. Die Ikonographie dieses Heiligenbildes geht mit einiger Wahrscheinlichkeit auf
eine Bildschöpfung der ersten Hälfte des 6. Jahrhunderts zurück. Der Bildtypus mit dem vor der Brust gehaltenen kleinen Kreuz ist ein Novum in der Kunst des 6. Jahrhunderts, der sich dauerhaft in der Heiligenikonographie der byzantinischen Kunst etabliert. Die Silberschale in Mainz stellt das wohl älteste fest datierte Zeugnis für diese richtungsweisende Ikonographie mit dem Attribut des kleinen Handkreuzes dar.
description: In 1977 an early Byzantine silver plate was purchased by the Römisch-Germanisches Zentralmuseum in Mainz. It is part of the group of silverware marked with five Imperial stamps. According to these stamps it was manufactured during the reign of Emperor Justinian I. (527-565), probably in the period between 527 and the middle of the 6th century and perhaps during the tenure of the comes sacrarum largitionum Flavios Strategios (532-539).
Owing to the specific head type the saint depicted in the central medallion of the plate can be identified as Theodore Tiron. The iconography of this image very probably originated during the first half of the 6th century. The type of image with the small cross held in front of his chest represents a novelty in the art of the 6th century, an image which would become well-established in the iconography of the saints in Byzantine art. The silver plate in Mainz seems to be the earliest securely dated example for this trend-setting iconography with the attribute of the small cross held in the hand.
A stable compound of helium and sodium at high pressure
Creators: name: Dong, Xiao
name: Oganov, Artem R.
name: Goncharov, Alexander F.
name: Stavrou, Elissaios
name: Lobanov, Sergey
name: Saleh, Gabriele
name: Qian, Guang-Rui
name: Zhu, Qiang
name: Gatti, Carlo
name: Deringer, Volker L.
name: Dronskowski, Richard
name: Zhou, Xiang-Feng
name: Prakapenka, Vitali B.
name: Konôpková, Zuzana
name: Popov, Ivan A.
name: Boldyrev, Alexander I.
name: Wang, Hui-Tian
Publisher: name: arXiv
Year: 2013
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Helium is generally understood to be chemically inert and this is due to its extremely stable closed-shell electronic configuration, zero electron affinity and an unsurpassed ionization potential. It is not known to form thermodynamically stable compounds, except a few inclusion compounds. Here, using the ab initio evolutionary algorithm USPEX and subsequent high-pressure synthesis in a diamond anvil cell, we report the discovery of a thermodynamically stable compound of helium and sodium, Na2He, which has a fluorite-type structure and is stable at pressures >113 GPa. We show that the presence of He atoms causes strong electron localization and makes this material insulating. This phase is an electride, with electron pairs localized in interstices, forming eight-centre two-electron bonds within empty Na8 cubes. We also predict the existence of Na2HeO with a similar structure at pressures above 15 GPa.
Lax matrix solution of c=1 Conformal Field Theory
Creators: name: Eynard, Bertrand
name: Ribault, Sylvain
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: To a correlation function in a two-dimensional conformal field theory with the central charge $c=1$, we associate a matrix differential equation $Ψ' = L Ψ$, where the Lax matrix $L$ is a matrix square root of the energy-momentum tensor. Then local conformal symmetry implies that the differential equation is isomonodromic. This provides a justification for the recently observed relation between four-point conformal blocks and solutions of the Painlevé VI equation. This also provides a direct way to compute the three-point function of Runkel-Watts theory -- the common $c\rightarrow 1$ limit of Minimal Models and Liouville theory.
description: 20 pages, v3: Corrected sign mistakes in eqs. (4.35), (4.37), (4.42), (4.45) and (4.52). Conclusions unchanged
title: On the use of caves in the Christian world during the Early Middle Ages (7th-10th century)
Creators: name: Schulze-Dörrlamm, Mechthild
Publisher: name: University Library Heidelberg
Year: 2014

description: Es ist derzeit kaum bekannt, dass Höhlen von der christlichen Bevölkerung Europas und der kleinasiatischen Provinzen des Byzantinischen Reiches während des 7. bis 10. Jahrhundert sehr intensiv genutzt wurden. Die
Gründe dafür waren teils profaner, teils religiöser Natur. Zahlreiche Höhlen dienten als Zufluchtsorte, in denen sich bedrohte Menschen zunächst vor den Angriffen arabischer Reiterheere, später auch vor den Überfällen muslimischer Sarazenen, der Wikinger und Ungarn in Sicherheit brachten oder zumindest ihre Schätze versteckten. Besonders viele Höhlen wurden dagegen von Eremiten bewohnt oder zu Höhlen-Kirchen ausgebaut. Allerdings hat man nur wenige Kulthöhlen der Antike in christliche Kultstätten umgewandelt, z. B. die Grotte des Erzengels Michael auf dem Monte Gargano und die vermeintliche Cacus-Höhle unter S. Maria in Cosmedin (Rom). Vor allem fällt auf, dass die verlassenen Höhlen des Mithras-Kultes nicht zu Höhlen-Kirchen gemacht, sondern allenfalls von Kirchen überbaut worden sind. Zweifelsfreie archäologische Belege für das Fortdauern heidnischer bzw. abergläubischer Opferhandlungen in Höhlen gibt es nicht, auch nicht in der berühmten spätrömischen Kulthöhle von Zillis im Kt. Graubünden.

description: At present it is almost unknown that caves were used very intensively by the Christian population of Europe and the Asia Minor provinces of the Byzantine Empire during the 7th to 10th century. The reasons for this
were partly profane, partly religious. Numerous caves served as places of refuge in which threatened people sought security or, at least, hid their valuables, initially from the attacks of Arab mounted armies, later from the raids of Moslem Saracens, Vikings and Hungary. On the other hand especially many caves were inhabited by hermits or developed into cave-churches. However, only a few cult-caves from Antiquity were turned into places of Christian worship, e. g. the grotto of the Archangel Michael on the Monte Gargano und the supposed cave of Cacus beneath Santa Maria in Cosmedin in Rome. In particular, it is apparent that the deserted caves of the Mithras cult were not turned into cave-churches, but at most were built over by churches. There is no clear archaeological evidence for the survival of heathen or superstitious offerings in caves, even in the famous Late Roman cult-cave of Zillis in the canton of Graubünden.
Visualizing Characters and Evaluating their Balance in Competitive Video Games
Creators: Saravanan, Akash
Publisher: name: University of Alberta Library
Year: 2023

Many competitive online video games release new characters on a regular basis. Designing these characters requires significant effort on several aspects including art, story, music, and game balance. Thus automating the design of these aspects offers value in saving human effort.

This thesis offers two major contributions to the open problem of video game character generation.

Our first contribution is a novel methodology for representing pixel art. We introduce the Pixel VQ-VAE, an enhanced VQ-VAE model with two enhancements to improve performance on pixel art. We demonstrate that our approach outperforms standard approaches in representational quality on two different datasets. We further apply the learned representations on two downstream tasks.

Our second contribution is a framework to evaluate changes to game balance via a process known as meta discovery. We use this meta discovery framework to simulate a large number of games and analyze the resultant game state. In developing this framework we train several reinforcement learning agents to approximate average human players and introduce a dynamic team-generation system. We demonstrate the effectiveness of the framework in approximating the results of balance changes on Pokémon Showdown, a competitive online battle simulator.
Recipe for inferring sub-surface solar magnetism via local mode-coupling using Slepian basis functions
Creators: name: Das, Srijan Bharati
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Direct seismic imaging of sub-surface flow, sound-speed and magnetic field is crucial for predicting flux tube emergence on the solar surface, an important ingredient for space weather. The sensitivity of helioseismic mode-amplitude cross-correlation to $p$- and $f$-mode oscillations enable formal inversion of such sub-photospheric perturbations. It is well-known that such problems are written in the form of an integral equation that connects the perturbations to the observations via ``sensitivity kernels". While the sensitivity kernels for flow and sound-speed have been known for decades and have been used extensively, formulating kernels for general magnetic perturbations had been elusive. A recent study proposed sensitivity kernels for Lorentz-stresses corresponding to global magnetic fields of general geometry. The present study is devoted to proposing kernels for inferring Lorentz-stresses as well as the solenoidal magnetic field in a local patch on the Sun via Cartesian mode-coupling. Moreover, for the first time in solar physics, Slepian functions are employed to parameterize perturbations in the horizontal dimension. This is shown to increase the number of data constraints in the inverse problem, implying an increase in the precision of inferred parameters. This paves the path to reliably imaging sub-surface solar magnetic features in, e.g., supergranules, sunspots and (emerging) active regions.
description: 18 pages, 5 figures; Accepted for publication in the Astrophysical Journal
The Cardinality of Sumsets: Different Summands
Creators: name: Murphy, Brendan
name: Palsson, Eyvindur Ari
name: Petridis, Giorgis
Publisher: name: arXiv
Year: 2013
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 11B30

description: Let $h$ be a positive integer and $A, B_1, B_2,\dots, B_h$ be finite sets in a commutative group. We bound $|A+B_1+...+B_h|$ from above in terms of $|A|, |A+B_1|,\dots,|A+B_h|$ and $h$. Extremal examples, which demonstrate that the bound is asymptotically sharp in all the parameters, are furthermore provided.
description: 25 pages. A minor change in the statement of Lemma 5.13
Exact quantum dynamics developments for floppy molecular systems and complexes
Creators: name: Mátyus, Edit
name: Daría, Alberto Martín Santa
name: Avila, Gustavo
Publisher: name: arXiv
Year: 2022
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Molecular rotation, vibration, internal rotation, isomerization, tunneling, intermolecular dynamics of weakly and strongly interacting systems, intra-to-inter-molecular energy transfer, hindered rotation and hindered translation over surfaces are important types of molecular motions. Their fundamentally correct and detailed description can be obtained by solving the nuclear Schrödinger equation on a potential energy surface. Many of the chemically interesting processes involve quantum nuclear motions which are `delocalized' over multiple potential energy wells. These `large-amplitude' motions in addition to the high dimensionality of the vibrational problem represent challenges to the current (ro)vibrational methodology. A review of the quantum nuclear motion methodology is provided, current bottlenecks of solving the nuclear Schrödinger equation are identified, and solution strategies are reviewed. Technical details, computational results, and analysis of these results in terms of limiting models and spectroscopically relevant concepts are highlighted for selected numerical examples.
Misinformation on Social Media: An Exploratory Sequential Mixed Methods Analysis of Users' Engagement with Religious Misinformation
Creators: Zaman, Md Sayeed Al
Publisher: name: University of Alberta Library
Year: 2023

Bangladesh, the world’s fourth-largest Muslim country, has a growing community of social media users. With the increasing social media usage, misinformation emerging from social media also becomes widespread in the country. In particular, religious misinformation has become more commonplace, inspiring violence against minorities and threatening interreligious harmony. Unfortunately, a lack of research prevents understanding Bangladesh’s multifaceted online religious misinformation problem. This research endeavors to fill this gap. Following an exploratory sequential mixed methods analysis combining a qualitative thematic analysis and a quantitative content analysis, this study analyzed Bangladeshi users’ Facebook data to answer two related research questions: (RQ1) How do social media users engage with religious misinformation? (RQ2) What are the frequencies of users’ different types of engagement? The qualitative analysis found three types of engagement: their topics of discourse, reactions to misinformation, and misinformation appraisal. Users’ discourse revolves around religious, radical, and political issues. Their expressions can be explained as positive and negative. The analysis also suggested that users appraise misinformation in four ways: trusting misinformation, denying misinformation, doubting misinformation, and no appraisal. The quantitative analysis of the second part of this study extended the qualitative findings, providing relevant statistical insights. It shows that radical issues (60.4%) dominate users’ discourse, followed by political issues (37.1%). In most cases, users’ reactions are negative (94.1%), exhibiting different destructive behaviors. Alarmingly, the negative reactions are more than seventeen times the positive reactions (5.5%). Results for misinformation appraisal suggest that 69.3% of users believe misinformation, and less than half of the believers (25.9%) can identify and deny misinformation. Users who both talk radical, react negatively, and trust misinformation comprise nearly half (48.21%) of the total users. Theoretical concepts, such as online vigilantism, destructive behavior, misinformation evaluation sets, and political Islam, help explain users’ various engagements with religious misinformation. I end with a discussion of some limitations and recommendations.
The Stochastic Solution to a Cauchy Problem for Degenerate Parabolic Equations
Creators: name: Chen, Xiaoshan
name: Huang, Yu-Jui
name: Song, Qingshuo
name: Zhu, Chao
Publisher: name: arXiv
Year: 2013
Subjects: subject: Probability (math.PR)
subject: Pricing of Securities (q-fin.PR)
subject: FOS: Mathematics
subject: FOS: Economics and business

description: We study the stochastic solution to a Cauchy problem for a degenerate parabolic equation arising from option pricing. When the diffusion coefficient of the underlying price process is locally Hölder continuous with exponent $δ\in (0, 1]$, the stochastic solution, which represents the price of a European option, is shown to be a classical solution to the Cauchy problem. This improves the standard requirement $δ\ge 1/2$. Uniqueness results, including a Feynman-Kac formula and a comparison theorem, are established without assuming the usual linear growth condition on the diffusion coefficient. When the stochastic solution is not smooth, it is characterized as the limit of an approximating smooth stochastic solutions. In deriving the main results, we discover a new, probabilistic proof of Kotani's criterion for martingality of a one-dimensional diffusion in natural scale.
description: Keywords: local martingales, local stochastic solutions, degenerate Cauchy problems, Feynman-Kac formula, necessary and sufficient condition for uniqueness, comparison principle
Knowledge Graph Population from Conversations
Creators: Strobl, Michael
Publisher: name: University of Alberta Library
Year: 2023

This thesis describes the design of a system that is capable of the generation of a Knowledge Graph (KG), referred to as Knowledge Graph Population (KGP), from conversations, specifically with elderly people. While this system still follows a traditional KGP approach with Entity Recognition (ER), Entity Linking (EL) and Relation Extraction (RE), we propose novel approaches for: (1) Annotating Wikipedia with Named Entities exhaustively in order to extract datasets for a variety of NLP tasks. (2) An interactive system to test and visualize the output of a KGP system based on a conversation. (3) Fast and accurate dataset creation for RE. (4) Dataset creation as well as training procedures for partially annotated ER datasets. (5) KG Question Answering (KGQA) using RE datasets for KGP instead of solely relying on dedicated KGQA datasets, not necessarily suited to the KG at hand.

A KG consists of nodes, corresponding to distinct entities, and edges, corresponding to semantic relations that link entities to each other. The main concern is composed of three topics: Family/Friends, Health, and Nutrition. We chose these since they are the main topics we think elderly people are interested in during daily conversations. The KGP follows a pipeline consisting of three systems: (1) ER, (2) EL and (3) RE. ER is concerned with finding entities of interest, mainly named entities and entities related to the topics Nutrition and Health. The EL system aims to link mentions of entities found by the ER system to their corresponding KG nodes or create a new one if not existing. The RE system then tries to find evidence in utterances that link entities to each other. In order to test the resulting KG, a KG Question Answering (KGQA) system is used to translate natural language questions into structured queries to retrieve answers from the KG. In addition, future tasks, such as response generation, could take advantage of such a KG in order to continue a conversation by creating informative utterances using the gained knowledge from previous utterances from the current or previous conversations in a structured way.
title: Zusammenfassung: Alberto Fernández. Die Anfänge des Kupferstichs in Granada
Creators: name: Pérez Galdeano, Ana María
Publisher: name: University Library Heidelberg
Year: 2014

description: Diese Arbeit analysiert die historischen und archivalischen Quellen, die zur Kontextualisierung der Anfänge der Tiefdruckgrafik in Granada von Hand des Silberschmiedes Alberto Fernández beitragen, dessen Herkunft noch unbekannt ist. Die gefundenen historiografischen Verweise auf seine Arbeit und deren Analyse werden die Hauptsäulen sein, die uns ermöglichen, neue Kenntnisse und Rückschlüsse auf den Umfang seiner Arbeit als Silberschmied und Stecher und zur Definition des Kupferstichs in Granada zu erarbeiten.
title: Denkmalpflege - vor allem ein menschliches Anliegen
Creators: name: Niester, Heinrich
Publisher: name: University Library Heidelberg
Year: 2014

description: Denkmalpflege in Baden-Württemberg – Nachrichtenblatt der Landesdenkmalpflege, Bd. 2, Nr. 1 (1959): Nachrichtenblatt der Denkmalpflege in Baden-Württemberg – Organ der Staatlichen Ämter für Denkmalpflege, Beginn und Erscheinungsfrequenz: Ausgaben pro Band: 4
Common origin of $θ_{13}$ and dark matter within the flavor symmetric scoto-seesaw framework
Creators: name: Ganguly, Joy
name: Gluza, Janusz
name: Karmakar, Biswajit
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: To understand the observed pattern of neutrino masses and mixing as well as to account for the dark matter we propose a hybrid scoto-seesaw model based on the $A_4$ discrete flavor symmetry. In this setup, including at least two heavy right-handed neutrinos is essential to employ the discrete flavor symmetry that mimics once popular tribimaximal neutrino mixing at the leading order via type-I seesaw. The scotogenic contribution then acts as a critical deviation to reproduce the observed value of the reactor mixing angle $θ_{13}$ (within the trimaximal mixing scheme) and to accommodate potential dark matter candidates, pointing towards a common origin of $θ_{13}$ and dark matter. The model predicts the atmospheric angle to be in the upper octant, excludes some regions on the Dirac CP phase, and restricts the Majorana phases too. Further, normal and inverted mass hierarchies can be distinguished for specific values of the relative phases associated with the complex light neutrino mass matrix. Owing to the considered flavor symmetry, contributions coming from the scotogenic mechanism towards the lepton flavor violating decays such as $μ\rightarrow e γ$, $τ\rightarrow e γ$ vanish, and a lower limit on the second right-handed neutrino mass can be obtained. Prediction for the effective mass parameter appearing in the neutrinoless double beta decay falls within the sensitivity of future experiments such as LEGEND-1k and nEXO.
description: 42 pages, 16 figures, 6 tables ; Version accepted for publication in JHEP