cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Rates of convergence to non-degenerate asymptotic profiles for fast diffusion via energy methods
Creators: name: Akagi, Goro
Publisher: name: arXiv
Year: 2021
Subjects: subject: Analysis of PDEs (math.AP)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: Primary: 35K67, Secondary: 35B40, 35B35

description: This paper is concerned with a quantitative analysis of asymptotic behaviors of (possibly sign-changing) solutions to the Cauchy-Dirichlet problem for the fast diffusion equation posed on bounded domains with Sobolev subcritical exponents. More precisely, rates of convergence to non-degenerate asymptotic profiles will be revealed via an energy method. The sharp rate of convergence to \emph{positive} ones was recently discussed by Bonforte and Figalli (2021, CPAM) based on an entropy method. An alternative proof for their result will also be provided. Furthermore, dynamics of fast diffusion flows with changing signs will be discussed more specifically under concrete settings; in particular, exponential stability of some sign-changing asymptotic profiles will be proved in dumbbell domains for initial data with certain symmetry.
ScreeNOT: Exact MSE-Optimal Singular Value Thresholding in Correlated Noise
Creators: name: Donoho, David L.
name: Gavish, Matan
name: Romanov, Elad
Publisher: name: arXiv
Year: 2020
Subjects: subject: Statistics Theory (math.ST)
subject: Methodology (stat.ME)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences

description: We derive a formula for optimal hard thresholding of the singular value decomposition in the presence of correlated additive noise; although it nominally involves unobservables, we show how to apply it even where the noise covariance structure is not a-priori known or is not independently estimable. The proposed method, which we call ScreeNOT, is a mathematically solid alternative to Cattell's ever-popular but vague Scree Plot heuristic from 1966. ScreeNOT has a surprising oracle property: it typically achieves exactly, in large finite samples, the lowest possible MSE for matrix recovery, on each given problem instance - i.e. the specific threshold it selects gives exactly the smallest achievable MSE loss among all possible threshold choices for that noisy dataset and that unknown underlying true low rank model. The method is computationally efficient and robust against perturbations of the underlying covariance structure. Our results depend on the assumption that the singular values of the noise have a limiting empirical distribution of compact support; this model, which is standard in random matrix theory, is satisfied by many models exhibiting either cross-row correlation structure or cross-column correlation structure, and also by many situations where there is inter-element correlation structure. Simulations demonstrate the effectiveness of the method even at moderate matrix sizes. The paper is supplemented by ready-to-use software packages implementing the proposed algorithm: package ScreeNOT in Python (via PyPI) and R (via CRAN).
Synthesis of Unnatural Tryptophan Analogs to Investigate the Molecular Recognition of Methylated Lysine by the HP1 Chromodomain
Creators: name: Tsai, Mary Kaitlyn
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: DNA is wrapped around a histone protein bundle, and these histone proteins can undergo post-translational modifications which then participate in signaling pathways to regulate important cellular functions. One such histone modification is methylation, where lysine can be mono, di, or tri-methylated. Reader proteins bind to methyl lysine and serve as docking sites for additional proteins that alter gene expression or chromatin structure. Dysregulation of histone methylation has been associated with certain types of cancer; therefore, it is necessary to understand the driving forces for binding of methylated lysine by these reader proteins to aid the development of reader protein probes or inhibitors with the desired specificity. In this project, the cation- interaction between trimethylated lysine 9 (Kme3) of H3 and the Drosophila reader protein, HP1 chromodomain, is investigated. The binding site of HP1 is comprised of three aromatic amino acids, two tyrosine residues and a tryptophan. To better understand the contribution of tryptophan in this cation- binding event, an unnatural tryptophan analog is synthesized with 1 fluorine atom, which is highly electron-withdrawing, attached to the outer aromatic rung. Once synthesized, these unnatural analogs will then be inserted into the HP1 binding site. Comparative binding studies between the wild type and mutant protein with the Kme3 peptide will provide a better understanding of the cation- mechanism. If Kme3 binds less tightly to the mutated binding pockets, it will indicate the importance of the tryptophan- contribution to binding.
Freestanding and permeable nanoporous gold membranes for surface-enhanced Raman scattering
Creators: name: Wyss, Roman M.
name: Parzefall, Markus
name: Gruber, Cynthia M.
name: Busschaert, Sebastian
name: Schlichting, Karl-Philipp
name: Lightner, Carin Rae
name: Loertscher, Emanuel
name: Novotny, Lukas
name: Heeg, Sebastian
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Surface-enhanced Raman spectroscopy (SERS) demands reliable, high enhancement substrates in order to be used in different fields of application. Here, we introduce freestanding porous gold membranes (PAuM) as easy to produce, scalable, mechanically stable, and effective SERS substrates. We fabricate large-scale sub-30 thick PAuM, that form freestanding membranes with varying morphologies depending on the nominal gold thickness. These PAuM are mechanically stable for pressures up to $>3$ bar, and exhibit surface-enhanced Raman scattering with local enhancement factors of $10^4$ to $10^5$, which we demonstrate by wavelength-dependent and spatially resolved Raman measurements using graphene as a local Raman probe. Numerical simulations reveal that the enhancement arises from individual, nanoscale pores in the membrane acting as optical slot antennas. Our PAuM are mechanically stable, provide robust SERS enhancement for excitation power densities up to $10^6$W$\,$cm$^{-2}$, and may find use as a building block in flow-through sensor applications based on SERS.
description: Roman M. Wyss and Markus Parzefal contributed equally. Supporting Information included
Exploring SES effects on emotion and health
Creators: name: Feldman, Mallory
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Social and Behavioral Sciences
subject: Psychology
subject: FOS: Psychology

description: Emotion has been hypothesized to consist of several constituent “ingredients." These “ingredients” include physiological sensations, environmental contexts, and concept knowledge (implicating past experiences, language, and culture). Preliminary evidence suggests plausible relationships between SES and body awareness, environmental predictability, and socialization/culture each of which we speculate may contribute to SES differences in emotional experience and health. Here we (1) begin to explore such relationships using well-validated questionnaires from social, cognitive, and affective psychology and furthermore (2) consider the implication of such relationships on outcomes pertaining to COVID-19.
High-fidelity single-shot readout of single electron spin in diamond with spin-to-charge conversion
Creators: name: Zhang, Qi
name: Guo, Yuhang
name: Ji, Wentao
name: Wang, Mengqi
name: Yin, Jun
name: Kong, Fei
name: Lin, Yiheng
name: Yin, Chunming
name: Shi, Fazhan
name: Wang, Ya
name: Du, Jiangfeng
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Applied Physics (physics.app-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: High fidelity single-shot readout of qubits is a crucial component for fault-tolerant quantum computing and scalable quantum networks. In recent years, the nitrogen-vacancy (NV) center in diamond has risen as a leading platform for the above applications. The current single-shot readout of the NV electron spin relies on resonance fluorescence method at cryogenic temperature. However, the the spin-flip process interrupts the optical cycling transition, therefore, limits the readout fidelity. Here, we introduce a spin-to-charge conversion method assisted by near-infrared (NIR) light to suppress the spin-flip error. This method leverages high spin-selectivity of cryogenic resonance excitation and high flexibility of photonionization. We achieve an overall fidelity $>$ 95% for the single-shot readout of an NV center electron spin in the presence of high strain and fast spin-flip process. With further improvements, this technique has the potential to achieve spin readout fidelity exceeding the fault-tolerant threshold, and may also find applications on integrated optoelectronic devices.
Magnetically induced QCD Kondo effect
Creators: name: Ozaki, Sho
name: Itakura, Kazunori
name: Kuramoto, Yoshio
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Lattice (hep-lat)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The "QCD Kondo effect" stems from the color exchange interaction in QCD with non-Abelian property, and can be realized in a high-density quark matter containing heavy-quark impurities. We propose a novel type of the QCD Kondo effect induced by a strong magnetic field. In addition to the fact that the magnetic field does not affect the color degrees of freedom, two properties caused by the Landau quantization in a strong magnetic field are essential for the "magnetically induced QCD Kondo effect"; (1) dimensional reduction to 1+1-dimensions, and (2) finiteness of the density of states for lowest energy quarks. We demonstrate that, in a strong magnetic field $B$, the scattering amplitude of a massless quark off a heavy quark impurity indeed shows a characteristic behavior of the Kondo effect. The resulting Kondo scale is estimated as $Λ_{\rm K} \simeq \sqrt{e_qB}\ α_{s}^{1/3} {\rm{exp}}\{-{4}π/N_{c} α_{s} {\rm{log}}( 4 π/α_{s}) \}$ where $α_{s}$ and $N_c$ are the fine structure constant of strong interaction and the number of colors in QCD, and $e_q$ is the electric charge of light quarks.
description: 34 pages, 6 figures, version published in PRD
Probing Wilson loops in ${\cal N}=4$ Chern-Simons-matter theories at weak coupling
Creators: name: Griguolo, Luca
name: Leoni, Matias
name: Mauri, Andrea
name: Penati, Silvia
name: Seminara, Domenico
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: For three-dimensional ${\cal N}=4$ super Chern-Simons-matter theories associated to necklace quivers $U(N_0) \times U(N_1) \times \cdots U(N_{2r-1}) $, we study at quantum level the two kinds of 1/2 BPS Wilson loop operators recently introduced in arXiv:1506.07614. We perform a two-loop evaluation and find the same result for the two kinds of operators, so moving to higher loops a possible quantum uplift of the classical degeneracy. We also compute the 1/4 BPS bosonic Wilson loop and discuss the quantum version of the cohomological equivalence between fermionic and bosonic Wilson loops. We compare the perturbative result with the Matrix Model prediction and find perfect matching, after identification and remotion of a suitable framing factor. Finally, we discuss the potential appearance of three-loop contributions that might break the classical degeneracy and briefly analyse possible implications on the BPS nature of these operators.
description: 7 pages, 2 figures
Bouncing and coasting universe with exact quantum-classical correspondence
Creators: name: John, Moncy Vilavinal
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: When the scale factor of expansion of the universe is written as $ a(t)\equiv Ae^{α(t)}$, with $A$ as some real constant and $α(t)$ a real function, the gravitational action $I_G$ appears in the same form as the matter action $I_M$ for a homogeneous and isotropic scalar field with a specific scale factor-dependent potential. We observe that by making analytic continuation of the Lagrangian function in this $I_G$ to the complex plane of $α$, one can obtain terms corresponding to both parts of a total action that describes a viable cosmological model. The solution gives a bouncing and coasting universe, which first contracts and then expands linearly, with a smooth bounce in between them. Such a bounce, called a Tolman wormhole, is due to a Casimir-like negative energy that appears naturally in the solution. In a novel approach to quantum cosmology, we perform canonical quantization of the above model using the operator method and show that it can circumvent the operator ordering ambiguity in the conventional formalism. It leads to a quantum wave equation for the universe, solving which we get the interesting result that the universe is in a ground state with nonzero energy. This solution is different from the Wheeler-DeWitt wave function and possesses exact quantum-classical correspondence during all epochs.
description: This preprint has not undergone peer review or any post-submission improvements or corrections. The Version of Record of this article is published in International Journal of Theoretical Physics, and is available online at https://doi.org/10.1007/s10773-021-04956-0
Structure-Function Studies of Essential Centrosomal Proteins Associated with Primordial Dwarfism and Microcephaly
Creators: name: Speed, Sarah
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2015

description: Centrosomes, composed of a pair of centrioles surrounded by pericentriolar material (PCM), are the main microtubule-organizing centers in eukaryotic cells involved in essential cell processes including nucleation and organization of the mitotic spindle. Heritable genetic defects in centrosomal components resulting in centrosome misregulation have been linked with developmental diseases such as primordial dwarfism and microcephaly. Centrosomes mature and duplicate once per cell cycle in a tightly controlled manner through the recruitment of hundreds of proteins, but explicit details on its organization have remained elusive. In particular, the role of centrioles is to recruit and organize the surrounding PCM, yet it is not well understood how these structures are physically linked. Using Drosophila as a model organism, our study aimed to elucidate the structural scaffolds that bridge the centrioles and PCM through characterization of several candidate proteins shown to associate through a directed yeast 2 hybrid screen. These proteins – Asl, CNN, PLP, and Sas-4 – were characterized through biochemical analysis and through structural analysis using X-ray crystallography to understand how they form a scaffold in order to recruit maturation and duplication factors to the centrosome. We have shown that several of the protein fragments chosen for crystallographic studies are able to localize independently to the centrosome in Drosophila S2 cells indicating they contain important targeting and/or binding domains. Biochemical analyses have revealed binding interactions and secondary structure of important protein fragments. Through bacterial cloning and expression, we have purified protein for all fragments of interest, and crystallization trials are under way in order to obtain high-resolution structures of interaction domains, both independently and in complex with one another. By understanding the structural and biochemical properties of these proteins, we can further elucidate the regulation of centrosomes in vivo and more fully understand how their misregulation can lead to disease.
Computational frameworks for homogenization and multiscale stability analyses of nonlinear periodic metamaterials
Creators: name: Zhang, Guodong
name: Feng, Nan
name: Khandelwal, Kapil
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: This paper presents a consistent computational framework for multiscale 1st order finite strain homogenization and stability analyses of rate-independent solids with periodic microstructures. Based on the principle of multiscale virtual power, the homogenization formulation is built on a priori discretized microstructure, and algorithms for computing the matrix representations of the homogenized stresses and tangent moduli are consistently derived. The homogenization results lose their validity at the onset of 1st bifurcation, which can be computed from multiscale stability analysis. The multiscale instabilities include: a) microscale structural instability which is calculated by Bloch wave analysis; and b) macroscale material instability which is calculated by rank-1 convexity checks on the homogenized tangent moduli. Details on the implementation of the Bloch wave analysis are provided, including the selection of the wave vector space and the retrieval of the real-valued buckling mode from the complex-valued Bloch wave. Three methods are detailed for solving the resulted constrained eigenvalue problem - two condensation methods and a null-space based projection method. Both implementations of the homogenization and stability analyses are validated using numerical examples including hyperelastic and elastoplastic metamaterials. Various microscale buckling phenomena are also demonstrated by examining several representative metamaterial examples. Aligned with theoretical results, the numerical results show that the microscopic long wavelength buckling can be equivalently detected by the loss of rank-1 convexity of the homogenized tangent moduli.
description: 75 pages, 39 Figures
Ultrafast Laser-Induced Melting of Long-Range Magnetic Order in Multiferroic TbMnO3
Creators: name: Johnson, Jeremy A.
name: Kubacka, T.
name: Hoffmann, M. C.
name: Vicario, C.
name: de Jong, S.
name: Beaud, P.
name: Gruebel, S.
name: Huang, S. -W.
name: Huber, L.
name: Windsor, Y. W.
name: Bothschafter, E. M.
name: Rettig, L.
name: Ramakrishnan, M.
name: Alberca, A.
name: Patthey, L.
name: Chuang, Y. -D.
name: Turner, J. J.
name: Dakovski, G. L.
name: Lee, W. -S.
name: Minitti, M. P.
name: Schlotter, W.
name: Moore, R. G.
name: Hauri, C. P.
name: Koohpayeh, S. M.
name: Scagnoli, V.
name: Ingold, G.
name: Johnson, S. L.
name: Staub, U.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We performed ultrafast time-resolved near-infrared pump, resonant soft X-ray diffraction probe measurements to investigate the coupling between the photoexcited electronic system and the spin cycloid magnetic order in multiferroic TbMnO3 at low temperatures. We observe melting of the long range antiferromagnetic order at low excitation fluences with a decay time constant of 22.3 +- 1.1 ps, which is much slower than the ~1 ps melting times previously observed in other systems. To explain the data we propose a simple model of the melting process where the pump laser pulse directly excites the electronic system, which then leads to an increase in the effective temperature of the spin system via a slower relaxation mechanism. Despite this apparent increase in the effective spin temperature, we do not observe changes in the wavevector q of the antiferromagnetic spin order that would typically correlate with an increase in temperature under equilibrium conditions. We suggest that this behavior results from the extremely low magnon group velocity that hinders a change in the spin-spiral wavevector on these time scales.
description: 9 pages, 4 figures
Physical black holes in semiclassical gravity
Creators: name: Murk, Sebastian
name: Terno, Daniel R.
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We derive and critically examine the consequences that follow from the formation of a regular black or white hole horizon in finite time of a distant observer. In spherical symmetry, only two distinct classes of solutions to the semiclassical Einstein equations are self-consistent. Both are required to describe the formation of physical black holes and violate the null energy condition in the vicinity of the outer apparent horizon. The near-horizon geometry differs considerably from that of classical solutions. If semiclassical physics is valid, accretion into a black hole is no longer possible after the horizon has formed. In addition, the two principal generalizations of surface gravity to dynamical spacetimes are irreconcilable, and neither can describe the emission of nearly-thermal radiation. Comparison of the required energy and timescales with established semiclassical results suggests that if the observed astrophysical black holes indeed have horizons, their formation is associated with new physics.
description: 16 pages, 1 figure. Contribution to the proceedings of the 16th Marcel Grossmann meeting (5-10 July 2021) to be published by World Scientific. Fig.1a has been updated to indicate the quantum ergosphere. Comments welcome!
The Voice of the “Little Man”: Jesse Helms’s “Southern Viewpoint” in Conservative Media and Politics, 1960-1972
Creators: name: Jenkins, Jordan
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2019

description: While William F. Buckley and his peers at National Review offered intellectual credibility to the conservative movement in the 1960s, North Carolina journalist Jesse Helms provided political pragmatism and accessibility. As a former campaign advisor, Helms was deeply aware of the importance of connecting with the general public on an emotional level. While the conservative intelligentsia sneered at populist grassroots movements as “irresponsible conservatism” and grappled with liberals for intellectual supremacy, Helms shrewdly sought to bring the ideology formed in the ivory tower and pages of National Review to the people of Piedmont and coastal North Carolina. New Right intellectuals made American conservatism a respectable philosophy; Helms turned that philosophy into a viable political movement in North Carolina.
Prime Spectrum of the Ring of Adeles of a Number Field
Creators: name: Holgado, Álvaro Serrano
Publisher: name: arXiv
Year: 2021
Subjects: subject: Number Theory (math.NT)
subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: 13A15, 11R56 (Primary) 13C13, 13J99 (Secondary)

description: Much is known about the adele ring of an algebraic number field from the perspective of Harmonic Analysis and Class Field Theory. However, its ring-theoretical aspects are often ignored. Here we present a description of the prime spectrum of this ring and study some of the algebraic and topological properties of these prime ideals. We also study how they behave under separable extensions of the base field and give an indication of how this study can be applied in adele rings not of number fields.
description: 14 pages
Elementary Examples of Solutions to Bochner's Problem for Matrix Differential Operators
Creators: name: Casper, William
Publisher: name: arXiv
Year: 2015
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics

description: In this paper, we demonstrate an elementary method for constructing new solutions to Bochner's problem for matrix differential operators from known solutions. We then describe a large family of solutions to Bochner's problem, obtained from classical solutions, which include several examples known from the literature. By virtue of the method of construction, we show how one may explicitly identify a generating function for the associated sequence of monic w-orthogonal matrix polynomials p(x,n) as well as the associated algebra D(w) of all matrix differential operators for which the p(x,n) are eigenfunctions. We also include some general results on the structure of the algebra D(w).
description: 38 pages; expanded examples to higher dimensions; fixed issues with the previous definition of adjoint; modified main theorem to a simpler and cleaner version; rewrote introduction to be friendlier and more self-contained; added many additional references; fixed typos; added more general results about the structure of D(w)
Constraining modified gravity theories with physical black holes
Creators: name: Murk, Sebastian
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We review the constraints modified theories of gravity must satisfy to be compatible with the spherically symmetric black hole solutions of semiclassical gravity that describe the formation of an apparent horizon in finite time of a distant observer. The constraints are satisfied in generic modified gravity theories with up to fourth-order derivatives in the metric, indicating that the semiclassical solutions correspond to zeroth-order terms in perturbative solutions of these models. From an observational point of view, this result implies that it may not be possible to distinguish between the semiclassical theory and modifications including up to fourth-order derivatives based on the observation of an apparent horizon alone.
description: 8 pages. Contribution to the proceedings of the 16th Marcel Grossmann meeting (5-10 July 2021) to be published by World Scientific. Minor revisions and typo fixes in v2. Comments welcome!
Injectivity radius of manifolds with a Lie structure at infinity
Creators: name: Bui, Quang-Tu
Publisher: name: arXiv
Year: 2020
Subjects: subject: Differential Geometry (math.DG)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: Using Lie groupoids, we prove that the injectivity radius of a manifold with a Lie structure at infinity is positive.
Differentiability of the pressure in non-compact spaces
Creators: name: Iommi, Godofredo
name: Todd, Mike
Publisher: name: arXiv
Year: 2020
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics

description: Regularity properties of the pressure are related to phase transitions. In this article we study thermodynamic formalism for systems defined in non-compact phase spaces, our main focus being countable Markov shifts. We produce metric compactifications of the space which allow us to prove that the pressure is differentiable on a residual set and outside an Aronszajn null set in the space of uniformly continuous functions. We establish a criterion, the so called sectorially arranged property, which implies that the pressure in the original system and in the compactification coincide. Examples showing that the compactifications can have rich boundaries, for example a Cantor set, are provided.
description: To appear in Fund. Math
RDM training @ UGent (2017-2019)
Creators: name: Mertens, Myriam
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Information Literacy
subject: Library and Information Science
subject: Social and Behavioral Sciences
subject: data management planning
subject: DMP
subject: RDM
subject: research data
subject: research data management
subject: training

description: Training materials used for Research Data Management workshops & information sessions by Ghent University Library (December 2017- May 2019).
Solution of the string equations for asymmetric potentials
Creators: name: Waters, Patrick
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mathematical Physics (math-ph)
subject: Combinatorics (math.CO)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We consider the large $N$ expansion of the partition function for the Hermitian one-matrix model. It is well known that the coefficients of this expansion are generating functions $F^{(g)}$ for a certain kind of graph embedded in a Riemann surface. Other authors have made a simplifying assumption that the potential $V$ is an even function. We present a method for computing $F^{(g)}$ in the case that $V$ is not an even function. Our method is based on the string equations, and yields "valence independent" formulas which do not depend explicitly on the potential. We introduce a family of differential operators, the "string polynomials", which make clear the valence independent nature of the string equations.
description: 32 pages, 1 figure
Uncertainty as Unavoidable Good
Creators: name: Piotrowski, Michael
Publisher: name: Universität Bielefeld, Center for Uncertainty Studies (CeUS)
Year: 2023
Subjects: subject: 900
subject: uncertainty
subject: historiography
subject: causal models
subject: epistemology

description: In digital history, uncertainty is generally regarded as an unavoidable evil. One generally aims to reduce—and ideally resolve—uncertainty in data as much as possible. However, information systems are not designed to handle the absence of information; we discuss how both SQL’s seemingly simple Null marker and the TEI Guideline’s elaborate facilities for recording “certainty” fail to address the challenges posed by uncertainty. Neither is big data and a “digital historical positivism” a satisfactory answer: the causal models that underpin historical narratives do not simply emerge from a collection of facts. Here, it is necessary to distinguish between two types of uncertainty: historical uncertainty, which concerns the facts of the past, and historiographical uncertainty, which concerns the causal models constructed by historians. The latter results from different interpretations of the causal relations between the facts; given our limited knowledge of the past, it is ultimately irreducible. But it is also this uncertainty that allows us to construct the narratives we need for sense-making. We argue that in this sense uncertainty may be regarded as an unavoidable good and that we should aim to design computational frameworks that treat it as an asset rather than an obstacle.
Patterns of $C$- and $CP$-violation in hadronic $η$ and $η'$ three-body decays
Creators: name: Akdag, Hakan
name: Isken, Tobias
name: Kubis, Bastian
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We construct hadronic amplitudes for the three-body decays $η^{(\prime)}\toπ^+π^-π^0$ and $η'\toηπ^+π^-$ in a non-perturbative fashion, allowing for $C$- and $CP$-violating asymmetries in the $π^+π^-$ distributions. These amplitudes are consistent with the constraints of analyticity and unitarity. We find that the currently most accurate Dalitz-plot distributions taken by the KLOE-2 and BESIII collaborations confine the patterns of these asymmetries to a relative per mille level. Our dispersive representation allows us to extract the individual coupling strengths of the $C$- and $CP$-violating contributions arising from effective isoscalar and isotensor operators in $η^{(\prime)}\toπ^+π^-π^0$ and an effective isovector operator in $η'\toηπ^+π^-$, while the strongly different sensitivities to these operators can be understood from chiral power counting arguments.
description: 43 pages, 9 figures, 5 tables; v2: discussion extended, version published in JHEP; v3: incorporates an erratum that fixes the phases of the C-violating norms by hermiticity and time reversal
Cross-Cultural Usability for Product Customization on the Web
Creators: name: Perks, Kristian
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: The extent to which peoples’ usability assessments vary as a function of their
country of origin and the origin of the website in the context of custom products was
explored. Twenty-four adults (12 Germans and 12 Americans), ranging from the age
of 18 to 25, used four different interfaces to create their own custom product; two
interfaces were from organizations based in the US and the other two were from
organizations based in Germany. The performance of each culture depended on
visual and navigational design, and organizational location; each participant, when
completing the tasks, took efficiency and effectiveness into account. Satisfaction was
also dependent on efficiency, effectiveness and the overall information architecture
of the website. Based on the results, it can be seen that users of websites need
content and their overall experience to be designed to their individual needs,
including their culture.
A small 6-chromatic two-distance graph in the plane
Creators: name: Parts, Jaan
Publisher: name: arXiv
Year: 2020
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: We give a new, simple proof for the lower bound of the chromatic number of the Euclidean plane with two forbidden distances, based on a graph with only 16 vertices.
Disentangling random thermal motion of particles and collective expansion of source from transverse momentum spectra in high energy collisions
Creators: name: Wei, Hua-Rong
name: Liu, Fu-Hu
name: Lacey, Roy A.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: In the framework of a multisource thermal model, we describe experimental results of the transverse momentum spectra of final-state light flavour particles produced in gold-gold (Au-Au), copper-copper (Cu-Cu), lead-lead (Pb-Pb), proton-lead ($p$-Pb), and proton-proton ($p$-$p$) collisions at various energies, measured by the PHENIX, STAR, ALICE, and CMS Collaborations, by using the Tsallis-standard (Tsallis form of Fermi-Dirac or Bose-Einstein), Tsallis, and two- or three-component standard distributions which can be in fact regarded as different types of "thermometers" or "thermometric scales" and "speedometers". A central parameter in the three distributions is the effective temperature which contains information on the kinetic freeze-out temperature of the emitting source and reflects the effects of random thermal motion of particles as well as collective expansion of the source. To disentangle both effects, we extract the kinetic freeze-out temperature from the intercept of the effective temperature ($T$) curve as a function of particle's rest mass ($m_0$) when plotting $T$ versus $m_0$, and the mean transverse flow velocity from the slope of the mean transverse momentum ($\langle p_T \rangle$) curve as a function of mean moving mass ($\overline{m}$) when plotting $\langle p_T \rangle$ versus $\overline{m}$.
description: 19 pages, 12 figures. Journal of Physics G, accepted
Intrapartum Nurses' Attitudes in Tertiary Care Settings
Creators: name: Chir, Alexandra
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2015

description: While childbirth and newborn care is one of the leading reasons for hospitalization in the United
States (Wier & Andrews, 2011), the US maternal health system is in need of some advancement.
A major issue surrounding maternity care in the United States consists of the medical field’s
medicalization of the birthing process. Although technological advances surrounding maternal
healthcare benefit those with high-risk pregnancies, they can hinder the birthing experiences of
those with low-risk pregnancies (McCool & Simeone, 2002). A force in advancing the US
maternal healthcare system, are intrapartum nurses working directly with patients, obstetricians,
midwives, doulas, and administrators. These nurses can only help to cause a positive change if
they have the attitude and behaviors that are favorable to that change. Using Dr. Icek Ajzen’s
theory of planned behavior that states one’s attitude can explain his or her behaviors (Ajzen,
1991) as the theoretical framework, this paper describes the importance of maintaining favorable
attitudes among intrapartum nurses in tertiary care setting to ensure the optimal birth experience
for patients. This paper also examines the resources that must be established in tertiary care
settings for intrapartum nurses to maintain such favorable attitudes surrounding the normalcy of
birth (Turnipseed & Turnipseed, 1991; Ivancevich & Matteson, 1980; Lee & Ahktar, 2007).
These resources include: continuous learning opportunities, clear job descriptions and
performance feedback, supervisory support and counseling assistance programs, and team
support (Ivancevich & Matteson, 1980; Lee & Ahktar, 2007).
From Stringy Particle Physics to Moduli Stabilisation and Cosmology
Creators: name: Honecker, Gabriele
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Intersecting D6-branes provide a geometrically intuitive road to stringy particle physics models, where D6-branes stuck at orbifold singularities can lead to the stabilisation of deformation moduli, and the QCD axion can arise from the open string sector in a very constrained way compared to pure field theory. We demonstrate this interplay of different physical features here through an explicit model.
description: 4 pages, contribution to the proceedings of "The String Theory Universe" Workshop in Leuven, 7-11 Sept 2015
Push button reproduction attempt of a research claim from Kucik, J., & Pelc, K. J. , (2016) in British Journal of Political Science
Creators: name: Talbert, Eli
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Political Science
subject: FOS: Political science
subject: Social and Behavioral Sciences

description: We selected the claim that early settlements are, on average, discriminatory – that is, they result in trade outcomes that disadvantage states not party to the consultative process (Statement 2). This reflects the following statement from the paper's abstract: "Looking at product-level trade flows from all disputes between 1995 and 2011, it finds that private (early) settlements lead to discriminatory trade outcomes – complainant countries gain disproportionately more than the rest of the membership" (Statement 1). The claim is tested with a new database containing dispute histories and trade flows for each WTO [World Trade Organization] dispute from DS1 to DS420 that names specific goods. The dependent variable, Disputed Imports, is the annual level of imports into defendant i from trade partner j in year t (logged). To test the claim that defendants should import more from complainants than from non-participants, the key variable of interest, Complainant (j,d), is coded 1 if a member j is a complainant in dispute d, and 0 otherwise (the reference category is all non-complainant WTO members). The analysis selected for the SCORE program is the fixed-effects model run on the sample of disputes that concluded with an early settlement (Model 2; see Table 1 for specification details) (Statement 3). In Model 2, complainants enjoy a clear benefit in cases that settle early when their trade flows are compared to the rest of the membership. This advantage is statistically significant at the 0.05 level, and it is substantively large: complainants receive a 68 per cent larger volume of post-dispute imports than the other members, on average (coefficient on Complainant (j,d) term = 0.430, clustered SE = 0.180, p < 0.05) (Statement 4) The focal test in the original paper is: coefficient on Complainant (j,d) term = 0.430, clustered SE = 0.180, p < 0.05
Fast Solution Methods for Fractional Differential Equations in the Modeling of Viscoelastic Materials
Creators: name: Diethelm, Kai
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 65R20, 65D25, 65L05

description: Fractional order models have proven to be a very useful tool for the modeling of the mechanical behaviour of viscoelastic materials. Traditional numerical solution methods exhibit various undesired properties due to the non-locality of the fractional differential operators, in particular regarding the high computational complexity and the high memory requirements. The infinite state representation is an approach on which one can base numerical methods that overcome these obstacles. Such algorithms contain a number of parameters that influence the final result in nontrivial ways. Based on numerical experiments, we initiate a study leading to good choices of these parameters.
description: 16 pages, 6 figures and 2 tables
INSPIRE: Intensity and spatial information-based deformable image registration
Creators: name: Öfverstedt, Johan
name: Lindblad, Joakim
name: Sladoje, Nataša
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: We present INSPIRE, a top-performing general-purpose method for deformable image registration. INSPIRE brings distance measures which combine intensity and spatial information into an elastic B-splines-based transformation model and incorporates an inverse inconsistency penalization supporting symmetric registration performance. We introduce several theoretical and algorithmic solutions which provide high computational efficiency and thereby applicability of the proposed framework in a wide range of real scenarios. We show that INSPIRE delivers highly accurate, as well as stable and robust registration results. We evaluate the method on a 2D dataset created from retinal images, characterized by presence of networks of thin structures. Here INSPIRE exhibits excellent performance, substantially outperforming the widely used reference methods. {We also evaluate INSPIRE on the Fundus Image Registration Dataset (FIRE), which consists of 134 pairs of separately acquired retinal images. INSPIRE exhibits excellent performance on the FIRE dataset, substantially outperforming several domain-specific methods.} We also evaluate the method on four benchmark datasets of 3D magnetic resonance images of brains, for a total of 2088 pairwise registrations. A comparison with 17 other state-of-the-art methods reveals that INSPIRE provides the best overall performance. Code is available at http://github.com/MIDA-group/inspire
description: 24 pages, 7 figures, 5 tables
Nonparametric estimation of the distribution of the autoregressive coefficient from panel random-coefficient AR(1) data
Creators: name: Leipus, Remigijus
name: Philippe, Anne
name: Pilipauskaitė, Vytautė
name: Surgailis, Donatas
Publisher: name: arXiv
Year: 2015
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics

description: We discuss nonparametric estimation of the distribution function $G(x)$ of the autoregressive coefficient $a \in (-1,1)$ from a panel of $N$ random-coefficient AR(1) data, each of length $n$, by the empirical distribution function of lag 1 sample autocorrelations of individual AR(1) processes. Consistency and asymptotic normality of the empirical distribution function and a class of kernel density estimators is established under some regularity conditions on $G(x)$ as $N$ and $n$ increase to infinity. The Kolmogorov-Smirnov goodness-of-fit test for simple and composite hypotheses of Beta distributed $a$ is discussed. A simulation study for goodness-of-fit testing compares the finite-sample performance of our nonparametric estimator to the performance of its parametric analogue discussed in Beran et al. (2010).
Atiyah sequences and connections on principal bundles over differentiable stacks
Creators: name: Biswas, Indranil
name: Chatterjee, Saikat
name: Koushik, Praphulla
name: Neumann, Frank
Publisher: name: arXiv
Year: 2020
Subjects: subject: Differential Geometry (math.DG)
subject: Category Theory (math.CT)
subject: FOS: Mathematics
subject: Primary 53C08, Secondary 22A22, 58H05, 53D50

description: We construct and study general connections on Lie groupoids and differentiable stacks as well as on principal bundles over them using Atiyah sequences associated to transversal tangential distributions.
description: To appear in Journal of Noncommutative Geometry
Factors Affecting the Interprofessional Communication and Teamwork Skills in a Simulation-Based Course
Creators: name: Ku, Jennifer
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Objective: To identify factors that affect teamwork and communication skills development among interprofessional teams of health professional students in a simulation based course.
Methods: 3 cohorts of 2-3 student teams completed 3-4 evaluated simulations. Interprofessional communication and teamwork skills were evaluated using a 16-question tool that awarded 0-2 points per question. Anomalies in team score trends were matched to course schedules coded by types of course activities.
Results: Average team scores were 84.38%, 100% and 100% in 2011; 48.96%, 97.92%, 92.71% and 97.92% in 2012; and 72.92%, 98.96%, 98.96% and 100% in 2013. In 2012, individual team scores were 100%, 100% and 78.13% for Simulation #3 and 100%, 96.88% and 96.88% for Simulation #2. Simulations #2 and #3 in 2012 were 6 weeks apart.
Conclusion: To maintain a high level of competency in teamwork and communication skills, interprofessional teams should consider doing simulations at least once every 4 weeks.
Threat, Emotion, and Ideo
Creators: name: Langer, Melanie
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Social and Behavioral Sciences

description: We investigate the relationship between ideology, perceived threat, emotions (particularly anger and fear), and political attitudes and behavior (e.g., vote choice and other forms of political engagement). We use independently collected data from the 2020 ANES to test all hypotheses.
Push button reproduction attempt of a research claim from Miller, R. A., & Elgün, Ö. (2011)., in Journal of Conflict Resolution
Creators: name: Talbert, Eli
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Social and Behavioral Sciences
subject: International and Area Studies

description: We selected the claim that as threats to political survival increase, the likelihood of conflict involvement increases (Hypothesis 1). This reflects the following statement from the paper’s abstract: “Our analysis of data from Latin America during the period 1960-99 reveals robust evidence in support of diversionary theory.” The authors use simultaneous equations to model the relationship between domestic and international politics. Tables 3 and 4 display estimates from models using the endogenous measure of the risk of coup events (along with control variables) to explain a nation’s involvement in international conflict. In Table 3, which contains the selected analysis, the dependent variable (Dispute) is defined as a state’s initiation of an MID [militarized interstate dispute], and the model selected uses Maddala-corrected standard errors (see Table 3 for details). In Table 3, the endogenous measure of the diversionary motivation — coup risk — is positive and statistically significant using the Maddala-corrected standard error (Coefficient = 2.96; Maddala Procedure SE = 1.51; p value = .051; significant at p ≤ .10 using a two-tailed test). The focal test in the original paper is: In Table 3, the endogenous measure of the diversionary motivation — coup risk — is positive and statistically significant using the Maddala-corrected standard error (Coefficient = 2.96; Maddala Procedure SE = 1.51; p value = .051; significant at p ≤ .10 using a two-tailed test).