cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
$\mathfrak{K}$-families and CPD-H-extendable families
Creators: name: Dey, Santanu
name: Trivedi, Harsh
Publisher: name: arXiv
Year: 2014
Subjects: subject: Operator Algebras (math.OA)
subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 46L07, 46L08, 46L53, 46L55

description: We introduce, for any set $S$, the concept of $\mathfrak{K}$-family between two Hilbert $C^*$-modules over two $C^*$-algebras, for a given completely positive definite (CPD-) kernel $\mathfrak{K}$ over $S$ between those $C^*$-algebras and obtain a factorization theorem for such $\mathfrak{K}$-families. If $\mathfrak{K}$ is a CPD-kernel and $E$ is a full Hilbert $C^*$-module, then any $\mathfrak{K}$-family which is covariant with respect to a dynamical system $(G,η,E)$ on $E$, extends to a $\tilde{\mathfrak{K}}$-family on the crossed product $E \times_ηG$, where $\tilde{\mathfrak{K}}$ is a CPD-kernel. Several characterizations of $\mathfrak{K}$-families, under the assumption that ${E}$ is full, are obtained and covariant versions of these results are also given. One of these characterizations says that such $\mathfrak{K}$-families extend as CPD-kernels, between associated (extended) linking algebras, whose $(2,2)$-corner is a homomorphism and vice versa. We discuss a dilation theory of CPD-kernels in relation to $\mathfrak{K}$-families.
description: 22 pages, 6 figures
On the normally ordered tensor product and duality for Tate objects
Creators: name: Braunling, Oliver
name: Groechenig, Michael
name: Heleodoro, Aron
name: Wolfson, Jesse
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Algebra (math.QA)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14A22, 18B30

description: This paper generalizes the normally ordered tensor product from Tate vector spaces to Tate objects over arbitrary exact categories. We show how to lift bi-right exact monoidal structures, duality functors, and construct external Homs. We list some applications: (1) Pontryagin duality uniquely extends to n-Tate objects in locally compact abelian groups; (2) Adeles of a flag can be written as ordered tensor products; (3) Intersection numbers can be interpreted via these tensor products.
description: updated to reflect published version and corrigendum
Effects of Spiral Arms on Star Formation in Nuclear Rings of Barred-spiral Galaxies
Creators: name: Seo, Woo-Young
name: Kim, Woong-Tae
Publisher: name: arXiv
Year: 2014
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We use hydrodynamic simulations to study the effect of spiral arms on the star formation rate (SFR) occurring in nuclear rings of barred-spiral galaxies. We find that spiral arms can be an efficient means of gas transport from the outskirts to the central parts, provided that the arms are rotating slower than the bar. While the ring star formation in models with no-arm or corotating arms is active only during about the bar growth phase, arm-driven gas accretion makes the ring star formation both enhanced and prolonged significantly in models with slow-rotating arms. The arm-enhanced SFR is larger by a factor of ~ 3-20 than in the no-arm model, with larger values corresponding to stronger and slower arms. Arm-induced mass inflows also make dust lanes stronger. Nuclear rings in slow-arm models are ~ 45% larger than in the no-arm counterparts. Star clusters that form in a nuclear ring exhibit an age gradient in the azimuthal direction only when the SFR is small, whereas no noticeable age gradient is found in the radial direction for models with arm-induced star formation.
description: 10 pages, 1 table, 6 figures, Accepted for publication in the ApJ
Новые данные по славянской гифронимии Албании
Creators: name: Ююкин, Максим
Publisher: name: Universita' degli Studi di Salerno
Year: 2018
Subjects: Hydronym
Etymology
Albania
Slavic colonization
Bulgarian language
Serbo-Croatian language

description: In the contemporary sources and databases, we can find at least 89 Albania’s river names of Slavic origin, that were not mentioned in the earlier research works (or were explained in a wrong way). The author discusses their etymology (using parallels from other Slavic territories), geographical distribution, semantic and word-formative types. The phonetic features of these names show that they are mostly of West Bulgarian descent (only three names are reliably attributed as the Serbo-Croatian, i.e. Old Shtokavian, ones) and were loaned by the Albanian language not earlier than in the 10-11th centuries, although there are several older loanwords.
How to design a multi-stage tournament when some results are carried over?
Creators: name: Csató, László
Publisher: name: arXiv
Year: 2017
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences
subject: 62F07, 68U20, 91A80, 91B14

description: The paper discusses the strategy-proofness of sports tournaments with multiple group stages, where the results of matches already played in the previous round against teams in the same group are carried over. These tournaments, widely used in handball and other sports, are shown to be incentive incompatible in the sense that a team can be strictly better off by not exerting full effort in a game. Historical examples are presented when a team was ex ante disinterested in winning by a high margin. We propose a family of incentive compatible designs. Their main characteristics are compared to the original format via simulations. Carrying over half of the points scored in the previous round turns out to be a promising policy.
description: 24 pages, 7 figures, 4 tables
The Moduli Space of Polynomial Maps and Their Fixed-Point Multipliers: II. Improvement to the Algorithm and Monic Centered Polynomials
Creators: name: Sugiyama, Toshi
Publisher: name: arXiv
Year: 2018
Subjects: subject: Dynamical Systems (math.DS)
subject: Algebraic Geometry (math.AG)
subject: Combinatorics (math.CO)
subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 37F10 (Primary) 05A19, 14D20 (Secondary)

description: We consider the family $\mathrm{MC}_d$ of monic centered polynomials of one complex variable with degree $d \geq 2$, and study the map $\widehatΦ_d:\mathrm{MC}_d\to \widetildeΛ_d \subset \mathbb{C}^d / \mathfrak{S}_d$ which maps each $f \in \mathrm{MC}_d$ to its unordered collection of fixed-point multipliers. We give an explicit formula for counting the number of elements of each fiber $\widehatΦ_d^{-1}\left(\barλ\right)$ for every $\barλ \in \widetildeΛ_d$ except when the fiber $\widehatΦ_d^{-1}\left(\barλ\right)$ contains polynomials having multiple fixed points. This formula is not a recursive one, and is a drastic improvement of our previous result [T. Sugiyama, The moduli space of polynomial maps and their fixed-point multipliers. Adv. Math. 322 (2017), 132--185] which gave a rather long algorithm with some induction processes.
description: 19 pages
Unitarily inequivalent quantum cosmological bouncing models
Creators: name: Martin, Jaime de Cabo
name: Małkiewicz, Przemysław
name: Peter, Patrick
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: By quantising the background as well as the perturbations in a simple one fluid model, we show that there exists an ambiguity in the choice of relevant variables, potentially leading to incompatible observational physical predictions. In a classical or quantum inflationary background, the exact same canonical transformations lead to unique predictions, so the ambiguity we put forward demands a semiclassical background with a sufficiently strong departure from classical evolution. The latter condition happens to be satisfied in bouncing scenarios, which may thus be having predictability issues. Inflationary models could evade such a problem because of the monotonic behavior of their scale factor; they do, however, initiate from a singular state which bouncing scenarios aim at solving.
description: 13 pages, 7 figures
Positivity and Kodaira embedding theorem
Creators: name: Ni, Lei
name: Zheng, Fangyang
Publisher: name: arXiv
Year: 2018
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: Kodaira embedding theorem provides an effective characterization of projectivity of a Kähler manifold in terms the second cohomology. Recently X. Yang [21] proved that any compact Kähler manifold with positive holomorphic sectional curvature must be projective. This gives a metric criterion of the projectivity in terms of its curvature. In this note, we prove that any compact Kähler manifold with positive 2nd scalar curvature (which is the average of holomorphic sectional curvature over 2-dimensional subspaces of the tangent space) must be projective. In view of generic 2-tori being non-abelian, this new curvature characterization is sharp in certain sense.
title: Transforaminal epidural steroid injections: Do needle position and foraminal stenosis affect the pattern of epidural flow?
Creators: name: Miskin, Nityanand
Publisher: name: European Society of Muscoskeletal Radiology
Year: 2018
Subjects: subject: Outcomes
subject: Contrast agent-other
subject: Percutaneous
subject: CT
subject: Musculoskeletal spine

description: Purpose Methods and Materials Results Conclusion References Personal Information
description: Purpose: The purpose of this study is to evaluate the influence of needle position and degree of foraminal stenosis with pattern of epidural contrast flow in CT-guided TFESI. As secondary outcome measures, the relationship between volume of contrast injected...
Tensor Regression with Applications in Neuroimaging Data Analysis
Creators: name: Zhu, Hongtu
name: Zhou, Hua
name: Li, Lexin
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Classical regression methods treat covariates as a vector and estimate a corresponding vector of regression coefficients. Modern applications in medical imaging generate covariates of more complex form such as multidimensional arrays (tensors). Traditional statistical and computational methods are proving insufficient for analysis of these high-throughput data due to their ultrahigh dimensionality as well as complex structure. In this article, we propose a new family of tensor regression models that efficiently exploit the special structure of tensor covariates. Under this framework, ultrahigh dimensionality is reduced to a manageable level, resulting in efficient estimation and prediction. A fast and highly scalable estimation algorithm is proposed for maximum likelihood estimation and its associated asymptotic properties are studied. Effectiveness of the new methods is demonstrated on both synthetic and real MRI imaging data.
title: Bone tumors around the knee: Imaging findings
Creators: name: Vieira, Ana
Publisher: name: European Society of Muscoskeletal Radiology
Year: 2018
Subjects: subject: Neoplasia
subject: Education and training
subject: Education
subject: Diagnostic procedure
subject: MR
subject: CT
subject: Conventional radiography
subject: Oncology
subject: Musculoskeletal bone
subject: Bones

description: Learning objectives Background Imaging findings OR Procedure Details Conclusion References Personal Information
description: Learning objectives: To present a description of bone tumors that most frequently arise around the knee, with main interest to the imaging...
Developing Structural, High-heat flux and Plasma Facing Materials for a near-term DEMO Fusion Power Plant: the EU Assessment
Creators: name: Stork, D.
name: Agostini, P.
name: Boutard, J-L.
name: Buckthorpe, D.
name: Diegele, E.
name: Dudarev, S. L.
name: English, C.
name: Federici, G.
name: Gilbert, M. R.
name: Gonzalez, S.
name: Ibarra, A.
name: Linsmeier, Ch.
name: Puma, A. Li
name: Marbach, G.
name: Morris, P. F.
name: Packer, L. W.
name: Raj, B.
name: Rieth, M.
name: Tran, M. Q.
name: Ward, D. J.
name: Zinkle, S. J.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The findings of the EU 'Materials Assessment Group' (MAG), within the 2012 EU Fusion Roadmap exercise, are discussed. MAG analysed the technological readiness of structural, plasma facing and high heat flux materials for a DEMO concept to be constructed in the early 2030s, proposing a coherent strategy for R&D up to a DEMO construction decision. Technical consequences for the materials required and the development, testing and modelling programmes, are analysed using: a systems engineering approach, considering reactor operational cycles, efficient maintenance and inspection requirements, and interaction with functional materials/coolants; and a project-based risk analysis, with R&D to mitigate risks from material shortcomings including development of specific risk mitigation materials.
description: 58 pages, 9 figures,Proceedings of the 16th International Conference on Fusion Reactor Materials (ICFRM-16), Beijing, China, 20th-26th October, 2013
Matroids on Eight Elements with the Half-plane Property and Related Concepts
Creators: name: Kummer, Mario
name: Sert, Büşra
Publisher: name: arXiv
Year: 2021
Subjects: subject: Combinatorics (math.CO)
subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 05B35, 90C22

description: We classify all matroids with at most 8 elements that have the half-plane property, and we provide a list of some matroids on 9 elements that have, and that do not have the half-plane property. Furthermore, we prove that several classes of matroids and polynomials that are motivated by the theory of semidefinite programming are closed under taking minors and under passing to faces of the Newton polytope.
description: Reviewed version is added
title: Imaging and diagnostic radiological aspiration of infected hip and knee prostheses
Creators: name: Morjaria, Anika
Publisher: name: European Society of Muscoskeletal Radiology
Year: 2018
Subjects: subject: Prostheses
subject: Diagnostic procedure
subject: Ultrasound
subject: MR
subject: Fluoroscopy
subject: Musculoskeletal joint

description: Learning objectives Background Imaging findings OR Procedure Details Conclusion References Personal Information
description: Learning objectives: This pictorial essay will discuss the role of the multimodality imaging approach to diagnosing prosthetic joint infection.Additionally, the role of the potential radiologist in performing diagnostic aspiration and sampling of prosthetic joints in...
Antiferromagnetic spin pumping via hyperfine interaction
Creators: name: Cahaya, Adam B.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Spin pumping is an interfacial spin current generation from the ferromagnetic layer to the non-magnetic metal at its interface. The polarization of the pumped spin current $\textbf{J}_s \propto \textbf{m}\times \dot{\textbf{m}}$ depends on the dynamics of the magnetic moment $\textbf{m}$. When the materials are based on light transition metals, mechanism behind the spin current transfer is dominated by the exchange interaction between spin of localized d-electrons and itinerant conduction electrons. In heavier transition metals, however, the interaction is not limited to the exchange interaction. The spin of the conduction electron can interact to its nuclear spin by means of hyperfine interaction, as observed in the shift of NMR frequency. By studying the spin polarization of conduction electron of the non-magnetic metallic layer due to a nuclear magnetic moment $\textbf{I}$ of the ferromagnetic layer, we show that the hyperfine interaction can mediate the spin pumping. The polarization of the spin current generation is shown to have a similar form $J_s\propto \textbf{I}\times\dot{\textbf{I}}$.
description: 8+ pages, 2 figures. International Conference on Hyperfine Interactions (HYPERFINE 2021)
Unified Analysis of Secondary Traits in Case–Control Association Studies
Creators: name: Zou, Fei
name: Ghosh, Arpita
name: Wright, Fred A.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: It has been repeatedly shown that in case-control association studies, analysis of a secondary trait which ignores the original sampling scheme can produce highly biased risk estimates. Although a number of approaches have been proposed to properly analyze secondary traits, most approaches fail to reproduce the marginal logistic model assumed for the original case-control trait and/or do not allow for interaction between secondary trait and genotype marker on primary disease risk. In addition, the flexible handling of covariates remains challenging. We present a general retrospective likelihood framework to perform association testing for both binary and continuous secondary traits which respects marginal models and incorporates the interaction term. We provide a computational algorithm, based on a reparameterized approximate profile likelihood, for obtaining the maximum likelihood (ML) estimate and its standard error for the genetic effect on secondary trait, in presence of covariates. For completeness we also present an alternative pseudo-likelihood method for handling covariates. We describe extensive simulations to evaluate the performance of the ML estimator in comparison with the pseudo-likelihood and other competing methods.
Some exit times estimates for Super-Brownian motion and Fleming-Viot Process
Creators: name: Fatheddin, Parisa
Publisher: name: arXiv
Year: 2018
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60H15, 92D25, 60F10

description: Estimates for exit time from an interval of length 2r before a prescribed time T are derived for solutions of a class of stochastic partial differential equations used to characterize two population models: super-Brownian motion and Fleming-Viot Process. These types of estimates are then derived for the two population models. The corresponding large deviation results are also applied for the acquired bounds.
Out-of-equilibrium phase transitions induced by Floquet resonances in a periodically quench-driven XY spin chain
Creators: name: Arze, Sergio Enrique Tapias
name: Claeys, Pieter W.
name: Castillo, Isaac Pérez
name: Caux, Jean-Sébastien
Publisher: name: arXiv
Year: 2018
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We consider the dynamics of an XY spin chain subjected to an external transverse field which is periodically quenched between two values. By deriving an exact expression of the Floquet Hamiltonian for this out-of-equilibrium protocol with arbitrary driving frequencies, we show how, after an unfolding of the Floquet spectrum, the parameter space of the system is characterized by alternations between local and non-local regions, corresponding respectively to the absence and presence of Floquet resonances. The boundary lines between regions are obtained analytically from avoided crossings in the Floquet quasi-energies and are observable as phase transitions in the synchronized state. The transient behaviour of dynamical averages of local observables similarly undergoes a transition, showing either a rapid convergence towards the synchronized state in the local regime, or a rather slow one exhibiting persistent oscillations in the non-local regime, where explicit decay coefficients are presented.
description: 26 pages, 50 references, 9 figures, 3 appendices
title: A Patello-femoral Pictorial Pathology Review
Creators: name: Lightfoot , Edward
Publisher: name: European Society of Muscoskeletal Radiology
Year: 2018
Subjects: subject: Anatomy
subject: Musculoskeletal joint
subject: Musculoskeletal system
subject: MR
subject: Imaging sequences
subject: Education
subject: Athletic injuries
subject: Education and training

description: Learning objectives Background Imaging findings OR Procedure Details Conclusion References Personal Information
description: Learning objectives: Review anatomy of the patellofemoral joint (PFJ) Systematic step-wise approach to assessment of the PFJ on magnetic resonance imaging (MRI) Review of a wide range of common pathology using multiple imaging modalities and comparing appearances with...
Poisson solvers for self-consistent multi-particle simulations
Creators: name: Qiang, J.
name: Paret, S.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Accelerator Physics (physics.acc-ph)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Self-consistent multi-particle simulation plays an important role in studying beam-beam effects and space charge effects in high-intensity beams. The Poisson equation has to be solved at each time-step based on the particle density distribution in the multi-particle simulation. In this paper, we review a number of numerical methods that can be used to solve the Poisson equation efficiently. The computational complexity of those numerical methods will be O(N log(N)) or O(N) instead of O(N2), where N is the total number of grid points used to solve the Poisson equation.
description: 5 pages, contribution to the ICFA Mini-Workshop on Beam-Beam Effects in Hadron Colliders, CERN, Geneva, Switzerland, 18-22 Mar 2013
A Likelihood-Based Framework for Association Analysis of Allele-Specific Copy Numbers
Creators: name: Zeng, D.
name: Lin, D. Y.
name: Hu, Y. J.
name: Sun, W.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2014

description: Copy number variants (CNVs) and single nucleotide polymorphisms (SNPs) co-exist throughout the human genome and jointly contribute to phenotypic variations. Thus, it is desirable to consider both types of variants, as characterized by allele-specific copy numbers (ASCNs), in association studies of complex human diseases. Current SNP genotyping technologies capture the CNV and SNP information simultaneously via fluorescent intensity measurements. The common practice of calling ASCNs from the intensity measurements and then using the ASCN calls in downstream association analysis has important limitations. First, the association tests are prone to false-positive findings when differential measurement errors between cases and controls arise from differences in DNA quality or handling. Second, the uncertainties in the ASCN calls are ignored. We present a general framework for the integrated analysis of CNVs and SNPs, including the analysis of total copy numbers as a special case. Our approach combines the ASCN calling and the association analysis into a single step while allowing for differential measurement errors. We construct likelihood functions that properly account for case-control sampling and measurement errors. We establish the asymptotic properties of the maximum likelihood estimators and develop EM algorithms to implement the corresponding inference procedures. The advantages of the proposed methods over the existing ones are demonstrated through realistic simulation studies and an application to a genome-wide association study of schizophrenia. Extensions to next-generation sequencing data are discussed.
title: The anatomy of acute injuries as revealed on MRI – demonstration of how muscle or tendon tears at some sites can reveal their complex arrangement
Creators: name: Ghany, Jehan
Publisher: name: European Society of Muscoskeletal Radiology
Year: 2018
Subjects: subject: Athletic injuries
subject: Education
subject: MR
subject: Musculoskeletal system
subject: Anatomy

description: Learning objectives Background Imaging findings OR Procedure Details Conclusion References Personal Information
description: Learning objectives: Demonstrate how through anaylsis of the muscle/tendon/ligament tear can reveal the underlining anatomy and help understand complex arrangements that are otherwise not so well appreciated in the normal form. High grade or significant tears of the...
Dipole amplitude with uncertainty estimate from HERA data and applications in Color Glass Condensate phenomenology
Creators: name: Lappi, T.
name: Mäntysaari, H.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We determine the initial condition for the small-$x$ evolution equation (BK) from the HERA deep inelastic scattering data using a new parametrization that also keeps the unintegrated gluon distribution positive. The obtained dipole amplitude and its uncertainty estimate can be used to compute single inclusive particle production in proton-proton and proton-nucleus collisions. We argue that one has to use consistently the proton transverse area measured in DIS and the total inelastic cross section when calculating the single inclusive cross section. This leads to a midrapidity nuclear modification factor $R_{pA}$ that approaches unity at large transverse momentum, independently of the center-of-mass energy.
description: 6 pages, 4 figures. Talk given by H.M. at XXII. International Workshop on Deep-Inelastic Scattering and Related Subjects
Measurement of light vector mesons and pi0 meson from the PHENIX experiment at RHIC
Creators: name: Acharya, Uttam
Publisher: name: Zenodo
Year: 2023
Subjects: pic23
phenix
π0
φ
qgp
small systems
p+au
d+au
3he+au
nuclear
modification
raa
centrality
photon
direct photon
forward-rapidity
au+au

description: Talk presented at the Physics in Collision 2023 conference
The order $p^8$ mesonic chiral Lagrangian
Creators: name: Bijnens, Johan
name: Hermansson-Truedsson, Nils
name: Wang, Si
Publisher: name: arXiv
Year: 2018
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We derive the chiral Lagrangian at next-to-next-to-next-to-leading order (NNNLO) for a general number $N_f$ of light quark flavours as well as for $N_f=2,3$. We enumerate the contact terms separately. We also discuss the cases where some of the external fields are not included. An example of a choice of Lagrangian is given in the supplementary material.
description: 23 pages, The file basis.pdf contains the full basis. Misprints in Lorentz indices in basis corrected w.r.t. v2
On spectral distribution of sample covariance matrices from large dimensional and large $k$-fold tensor products
Creators: name: Collins, Benoît
name: Yao, Jianfeng
name: Yuan, Wangjun
Publisher: name: arXiv
Year: 2021
Subjects: subject: Probability (math.PR)
subject: Mathematical Physics (math-ph)
subject: Combinatorics (math.CO)
subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We study the eigenvalue distributions for sums of independent rank-one $k$-fold tensor products of large $n$-dimensional vectors. Previous results in the literature assume that $k=o(n)$ and show that the eigenvalue distributions converge to the celebrated Marčenko-Pastur law under appropriate moment conditions on the base vectors. In this paper, motivated by quantum information theory, we study the regime where $k$ grows faster, namely $k=O(n)$. We show that the moment sequences of the eigenvalue distributions have a limit, which is different from the Marčenko-Pastur law. As a byproduct, we show that the Marčenko-Pastur law limit holds if and only if $k=o(n)$ for this tensor model. The approach is based on the method of moments.
description: 21 pages, 6 figures
Ultrastrong Coupling in the Near-field of Complementary Split Ring Resonators
Creators: name: Maissen, Curdin
name: Scalari, Giacomo
name: Valmorra, Federico
name: Cibella, Sara
name: Leoni, Roberto
name: Reichl, Christian
name: Charpentier, Christohpe
name: Wegscheider, Werner
name: Beck, Mattias
name: Faist, Jérôme
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The ultrastrong light-matter interaction regime was investigated in metallic and superconducting complementary split ring resonators coupled to the cyclotron transition of two dimensional electron gases. The sub-wavelength light confinement and the large optical dipole moment of the cyclotron transition yield record high normalized coupling rates of up to $\frac{Ω_R}{ω_c}=$ 0.87. We observed a blue-shift of both polaritons due to the diamagnetic term of the interaction Hamiltonian.
title: Navigational MR Arthrography for Femoroacetabular Impingement
Creators: name: Lightfoot , Edward
Publisher: name: European Society of Muscoskeletal Radiology
Year: 2018
Subjects: subject: Contrast agent-other
subject: Arthrography
subject: MR
subject: Pelvis
subject: Musculoskeletal joint
subject: Musculoskeletal bone
subject: Education and training

description: Learning objectives Background Imaging findings OR Procedure Details Conclusion References Personal Information
description: Learning objectives: Magnetic Resonance Arthrography (MRA) utility can be enhanced with surgically important navigational measurements. Our process and technique is explained. Case examples showing navigational measurements and how arthroscopic surgery...
Bayesian Generalized Low Rank Regression Models for Neuroimaging Phenotypes and Genetic Markers
Creators: name: Ibrahim, Joseph G.
name: Khondker, Zakaria
name: Zhu, Hongtu
name: Lu, Zhaohua
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2014

description: We propose a Bayesian generalized low rank regression model (GLRR) for the analysis of both high-dimensional responses and covariates. This development is motivated by performing searches for associations between genetic variants and brain imaging phenotypes. GLRR integrates a low rank matrix to approximate the high-dimensional regression coefficient matrix of GLRR and a dynamic factor model to model the high-dimensional covariance matrix of brain imaging phenotypes. Local hypothesis testing is developed to identify significant covariates on high-dimensional responses. Posterior computation proceeds via an efficient Markov chain Monte Carlo algorithm. A simulation study is performed to evaluate the finite sample performance of GLRR and its comparison with several competing approaches. We apply GLRR to investigate the impact of 1,071 SNPs on top 40 genes reported by AlzGene database on the volumes of 93 regions of interest (ROI) obtained from Alzheimer's Disease Neuroimaging Initiative (ADNI).
Spiking and collapsing in large noise limits of SDEs
Creators: name: Bernardin, Cédric
name: Chetrite, Raphaël
name: Chhaibi, Reda
name: Najnudel, Joseph
name: Pellegrini, Clément
Publisher: name: arXiv
Year: 2018
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: We analyze the strong noise limit of one-dimensional stochastic differential equations (SDEs). Our initial motivation comes from continuous measurements of open quantum systems. In this context, Bauer, Bernard and Tilloy pointed out an intriguing behavior. As the noise grows larger, the solutions exhibit locally a collapsing, that is to say, converge to pure jump processes very reminiscent of a metastability phenomenon. But surprisingly the limiting jump process is decorated by a spike process. We give a precise meaning to the convergence and completely prove these statements for a large class of one-dimensional diffusions, thanks to a robust strategy of proof.
description: v1: Preliminary version. v2: Expanded version treating the general two-boundary case and the case of Rabi oscillations. 29 pages, 3 figures
PantheonRL: A MARL Library for Dynamic Training Interactions
Creators: name: Sarkar, Bidipta
name: Talati, Aditi
name: Shih, Andy
name: Sadigh, Dorsa
Publisher: name: arXiv
Year: 2021
Subjects: subject: Multiagent Systems (cs.MA)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: We present PantheonRL, a multiagent reinforcement learning software package for dynamic training interactions such as round-robin, adaptive, and ad-hoc training. Our package is designed around flexible agent objects that can be easily configured to support different training interactions, and handles fully general multiagent environments with mixed rewards and n agents. Built on top of StableBaselines3, our package works directly with existing powerful deep RL algorithms. Finally, PantheonRL comes with an intuitive yet functional web user interface for configuring experiments and launching multiple asynchronous jobs. Our package can be found at https://github.com/Stanford-ILIAD/PantheonRL.
description: 3 pages, 3 figures. Published in Proceedings of the 36th AAAI Conference on Artificial Intelligence (Demo Track) 2022
CFTs on curved spaces
Creators: name: Kikuchi, Ken
Publisher: name: arXiv
Year: 2019
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We study conformal field theories (CFTs) on curved spaces including both orientable and unorientable manifolds possibly with boundaries. We first review conformal transformations on curved manifolds. We then compute the identity components of conformal groups acting on various metric spaces using a simple fact; given local coordinate systems be single-valued. Boundary conditions thus obtained which must be satisfied by conformal Killing vectors (CKVs) correctly reproduce known conformal groups. As a byproduct, on $\mathbb S^1_l\times\mathbb H^2_r$, by setting their radii $l=Nr$ with $N\in\mathbb N^\times$, we find (the identity component of) the conformal group enhances, whose persistence in higher dimensions is also argued. We also discuss forms of correlation functions on these spaces using the symmetries. Finally, we study a $d$-torus $\mathbb T^d$ in detail, and show the identity component of the conformal group acting on the manifold in general is given by $\text{Conf}_0(\mathbb T^d)\simeq U(1)^d$ when $d\ge2$. Using the fact, we suggest some candidates of conformal manifolds of CFTs on $\mathbb T^d$ without assuming the presence of supersymmetry (SUSY). In order to clarify which parts of correlation functions are physical, we also discuss renormalization group (RG) and local counterterms on curved spaces.
description: 71 pages; v2: comments and references added; v3: version published in ATMP
Infrastructure adaptation and emergence of loops in network routing with time-dependent loads
Creators: name: Lonardi, Alessandro
name: Facca, Enrico
name: Putti, Mario
name: De Bacco, Caterina
Publisher: name: arXiv
Year: 2021
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Dynamical Systems (math.DS)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Network routing approaches are widely used to study the evolution in time of self-adapting systems. However, few advances have been made for problems where adaptation is governed by time-dependent inputs. In this work we study a dynamical system where the edge conductivities of a network are regulated by time-varying mass loads injected on nodes. Motivated by empirical observations, we assume that conductivities adapt slowly with respect to the characteristic time of the loads. Furthermore, assuming the loads to be periodic, we derive a dynamics where the evolution of the system is controlled by a matrix obtained with the Fourier coefficients of the input loads. Remarkably, we find a sufficient condition on these coefficients that determines when the resulting network topologies are trees. We show an example of this on the Bordeaux bus network where we tune the input loads to interpolate between loopy and tree topologies. We validate our model on several synthetic networks and provide an expression for long-time solutions of the original conductivities.
description: 12 pages, 5 figures
Toroidal order in a partially disordered state on a layered triangular lattice: implication to UNi4B
Creators: name: Hayami, Satoru
name: Kusunose, Hiroaki
name: Motome, Yukitoshi
Publisher: name: arXiv
Year: 2014
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: A partial disorder on a layered triangular lattice is theoretically investigated from a viewpoint of toroidal ordering and magnetoelectric effects. We consider an extended periodic Anderson model including a site-dependent antisymmetric spin-orbit coupling between conduction and localized electrons. We show that, by the mean-field approximation, the model exhibits a coplanar vortex-lattice-type magnetic order as observed in a hexagonal uranium compound UNi4B, in the parameter region with intermediate hybridization and electron correlation. This peculiar state accommodates a toroidal order, which leads to the linear magnetoelectric effect. We discuss the implications of our results to UNi4B, focusing on the possible source of the site-dependent antisymmetric spin-orbit coupling.
description: 6 pages, 2 figures
On the dimension spectra of infinite iterated function systems
Creators: name: Das, Tushar
name: Simmons, David
Publisher: name: arXiv
Year: 2019
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 37D35, 28A80, 37B10

description: The dimension spectrum of a conformal iterated function system (CIFS) is the set of all Hausdorff dimensions of its various subsystem limit sets. This brief note provides two constructions -- (i) a compact perfect set that cannot be realized as the dimension spectrum of a CIFS; and (ii) a similarity IFS whose dimension spectrum has zero Hausdorff dimension, and thus is not uniformly perfect -- which resolve questions posed by Chousionis, Leykekhman, and Urbański, and go on provoke fresh conjectures and questions regarding the topological and metric properties of IFS dimension spectra.
Reciprocity, community detection, and link prediction in dynamic networks
Creators: name: Safdari, Hadiseh
name: Contisciani, Martina
name: De Bacco, Caterina
Publisher: name: arXiv
Year: 2021
Subjects: subject: Social and Information Networks (cs.SI)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Many complex systems change their structure over time, in these cases dynamic networks can provide a richer representation of such phenomena. As a consequence, many inference methods have been generalized to the dynamic case with the aim to model dynamic interactions. Particular interest has been devoted to extend the stochastic block model and its variant, to capture community structure as the network changes in time. While these models assume that edge formation depends only on the community memberships, recent work for static networks show the importance to include additional parameters capturing structural properties, as reciprocity for instance. Remarkably, these models are capable of generating more realistic network representations than those that only consider community membership. To this aim, we present a probabilistic generative model with hidden variables that integrates reciprocity and communities as structural information of networks that evolve in time. The model assumes a fundamental order in observing reciprocal data, that is an edge is observed, conditional on its reciprocated edge in the past. We deploy a Markovian approach to construct the network's transition matrix between time steps and parameters' inference is performed with an Expectation-Maximization algorithm that leads to high computational efficiency because it exploits the sparsity of the dataset. We test the performance of the model on synthetic dynamical networks, as well as on real networks of citations and email datasets. We show that our model captures the reciprocity of real networks better than standard models with only community structure, while performing well at link prediction tasks.
Efficient Estimation of Semiparametric Transformation Models for Two-Phase Cohort Studies
Creators: name: Lin, D. Y.
name: Zeng, Donglin
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2014

description: Under two-phase cohort designs, such as case-cohort and nested case-control sampling, information on observed event times, event indicators, and inexpensive covariates is collected in the first phase, and the first-phase information is used to select subjects for measurements of expensive covariates in the second phase; inexpensive covariates are also used in the data analysis to control for confounding and to evaluate interactions. This paper provides efficient estimation of semiparametric transformation models for such designs, accommodating both discrete and continuous covariates and allowing inexpensive and expensive covariates to be correlated. The estimation is based on the maximization of a modified nonparametric likelihood function through a generalization of the expectation-maximization algorithm. The resulting estimators are shown to be consistent, asymptotically normal and asymptotically efficient with easily estimated variances. Simulation studies demonstrate that the asymptotic approximations are accurate in practical situations. Empirical data from Wilms’ tumor studies and the Atherosclerosis Risk in Communities (ARIC) study are presented.
Proper Motion of the Draco Dwarf Galaxy Based On Hubble Space Telescope Imaging
Creators: name: Pryor, Carlton
name: Piatek, Slawomir
name: Olszewski, Edward W.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We have measured the proper motion of the Draco dwarf galaxy using images at two epochs with a time baseline of about two years taken with the Hubble Space Telescope and the Advanced Camera for Surveys. Wide Field Channel 1 and 2 provide two adjacent fields, each containing a known QSO. The zero point for the proper motion is determined using both background galaxies and the QSOs and the two methods produce consistent measurements within each field. Averaging the results from the two fields gives a proper motion in the equatorial coordinate system of $(μ_α,μ_δ) = (17.7\pm 6.3, -22.1 \pm 6.3)$ mas century$^{-1}$ and in the Galactic coordinate system of $(μ_{\ell},μ_{b}) = (-23.1\pm 6.3, -16.3 \pm 6.3)$ mas century$^{-1}$. Removing the contributions of the motion of the Sun and of the LSR to the measured proper motion yields a Galactic rest-frame proper motion of $(μ_α^{Grf},μ_δ^{Grf}) = (51.4\pm 6.3, -18.7 \pm 6.3)$ mas century$^{-1}$ and $(μ_{\ell}^{Grf},μ_{b}^{Grf}) = (-21.8\pm 6.3, -50.1 \pm 6.3)$ mas century$^{-1}$. The implied space velocity with respect to the Galactic center is $(Π, Θ, Z) = (27\pm 14, 89\pm 25, -212\pm 20)$ km s$^{-1}$. This velocity implies that the orbital inclination is 70 degrees, with a 95% confidence interval of (59 deg, 80 deg), and that the plane of the orbit is consistent with that of the vast polar structure (VPOS) of Galactic satellite galaxies.
description: 27 pages including 13 figures and 3 tables, submitted to AJ
A $\mathcal{C}^k$-Seeley-Extension-Theorem for Bastiani's Differential Calculus
Creators: name: Hanusch, Maximilian
Publisher: name: arXiv
Year: 2020
Subjects: subject: Functional Analysis (math.FA)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 46G05, 54C20, 58C20

description: We generalize a classical extension result by Seeley in the context of Bastiani's differential calculus to infinite dimensions. The construction follows Seeley's original approach, but is significantly more involved as not only $C^k$-maps (for $k\in \mathbb{N}\cup\{\infty\}$) on (subsets of) half spaces are extended, but also continuous extensions of their differentials to some given piece of boundary of the domains under consideration. A further feature of the generalization is that we construct families of extension operators (instead of only one single extension operator) that fulfill certain compatibility (and continuity) conditions. Various applications are discussed as well.
description: 29 pages. Version as published in Canadian Journal of Mathematics
Evidence of surface transport and weak anti-localization in single crystal of Bi2Te2Se topological insulator
Creators: name: Shekhar, Chandra
name: Barbosa, C. E. Viol
name: Yan, Binghai
name: Ouardi, Siham
name: Schnelle, W.
name: Fecher, Gerhard H.
name: Felser, Claudia
Publisher: name: arXiv
Year: 2014
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Topological insulators are known to their metallic surface states, a result of strong-spin-orbital coupling, that show unique surface transport phenomenon. But these surface transports are buried in presence of metallic bulk conduction. We synthesized very high quality Bi$_2$Te$_2$Se single crystals by modified Bridgman method, that possess high bulk resistivity of $>$20~$Ω$cm below 20~K, whereas the bulk is mostly inactive and surface transport dominates. Temperature dependence resistivity follows the activation law like a gap semiconductor in temperature range 20-300~K. We designed a special measurement geometry, which aims to extract the surface transport from the bulk. This special geometry is applied to measure the resistance and found that Bi$_2$Te$_2$Se single crystal exhibits a cross over from bulk to surface conduction at 20~K. Simultaneously, the material also shows strong evidence of weak anti-localization in magneto-transport due to the protection against scattering by conducting surface states. This novel simple geometry is an easy route to find the evidence of surface transport in topological insulators, which are the promising materials for future spintronic applications.
description: 6 Pages, 4 Figures
Large Sample Randomization Inference of Causal Effects in the Presence of Interference
Creators: name: Liu, Lan
name: Hudgens, Michael G.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2014

description: Recently, increasing attention has focused on making causal inference when interference is possible. In the presence of interference, treatment may have several types of effects. In this paper, we consider inference about such effects when the population consists of groups of individuals where interference is possible within groups but not between groups. A two stage randomization design is assumed where in the first stage groups are randomized to different treatment allocation strategies and in the second stage individuals are randomized to treatment or control conditional on the strategy assigned to their group in the first stage. For this design, the asymptotic distributions of estimators of the causal effects are derived when either the number of individuals per group or the number of groups grows large. Under certain homogeneity assumptions, the asymptotic distributions provide justification for Wald-type confidence intervals (CIs) and tests. Empirical results demonstrate the Wald CIs have good coverage in finite samples and are narrower than CIs based on either the Chebyshev or Hoeffding inequalities provided the number of groups is not too small. The methods are illustrated by two examples which consider the effects of cholera vaccination and an intervention to encourage voting.
title: What is the “Stripe sign”: Intramuscular soft tissue tumor or tumor-like lesion
Creators: name: Lee, Seunah
Publisher: name: European Society of Muscoskeletal Radiology
Year: 2018
Subjects: subject: Neoplasia
subject: Inflammation
subject: Education and training
subject: Education
subject: MR
subject: Musculoskeletal soft tissue

description: Learning objectives Background Imaging findings OR Procedure Details Conclusion References Personal Information
description: Learning objectives: •To introduce the "stripe sign" which represent the appearance of preserved muscle fibers without discontinuity within the soft tissue mass. •To understand that various intramuscular soft tissue tumors or tumor-like lesions can present the...