cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Entanglements and Whitehead Products: Generalizing Kleman's Construction to Higher-Dimensional Defects
Creators: name: Alexander, Gareth P.
name: Kamien, Randall D.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: General Topology (math.GN)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We review the interpretation of Whitehead products in homotopy theory as an entanglement of topological defects in ordered media.
description: 7 pages, figures, the whole megillah
Practical Blind Image Denoising via Swin-Conv-UNet and Data Synthesis
Creators: name: Zhang, Kai
name: Li, Yawei
name: Liang, Jingyun
name: Cao, Jiezhang
name: Zhang, Yulun
name: Tang, Hao
name: Fan, Deng-Ping
name: Timofte, Radu
name: Van Gool, Luc
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Graphics (cs.GR)
subject: Image and Video Processing (eess.IV)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: While recent years have witnessed a dramatic upsurge of exploiting deep neural networks toward solving image denoising, existing methods mostly rely on simple noise assumptions, such as additive white Gaussian noise (AWGN), JPEG compression noise and camera sensor noise, and a general-purpose blind denoising method for real images remains unsolved. In this paper, we attempt to solve this problem from the perspective of network architecture design and training data synthesis. Specifically, for the network architecture design, we propose a swin-conv block to incorporate the local modeling ability of residual convolutional layer and non-local modeling ability of swin transformer block, and then plug it as the main building block into the widely-used image-to-image translation UNet architecture. For the training data synthesis, we design a practical noise degradation model which takes into consideration different kinds of noise (including Gaussian, Poisson, speckle, JPEG compression, and processed camera sensor noises) and resizing, and also involves a random shuffle strategy and a double degradation strategy. Extensive experiments on AGWN removal and real image denoising demonstrate that the new network architecture design achieves state-of-the-art performance and the new degradation model can help to significantly improve the practicability. We believe our work can provide useful insights into current denoising research.
description: Codes: https://github.com/cszn/SCUNet
Main-Belt Comet 238P/Read Revisited
Creators: name: Hsieh, Henry H.
name: Meech, Karen J.
name: Pittichova, Jana
Publisher: name: arXiv
Year: 2011
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We present a series of observations of the return of activity in main-belt comet 238P/Read. Using data obtained in July and August 2010 when 238P appeared to be largely inactive, we find best-fit IAU phase function parameters of H=19.05+/-0.05 mag, corresponding to a nucleus radius of r_n ~ 0.4 km (assuming an albedo of p_R=0.05), and G=-0.03+/-0.05. Observations from September 2010 onward show a clear rise in activity, causing both a notable change in visible morphology and increasing photometric excesses beyond what would be expected based on bare nucleus observations. By the end of the observing period reported on here, the dust mass in the coma shows indications of reaching a level comparable to that observed in 2005, but further observations are highly encouraged once 238P again becomes observable from Earth in mid-2011 to confirm whether this level of activity is achieved, or if a notable decrease in activity strength compared to 2005 can be detected. Comet 238P is now the second main-belt comet (after 133P/Elst-Pizarro) observed to exhibit recurrent activity, providing strong corroboration for the conclusion that it is a true comet whose active episodes are driven by sublimation of volatile ice.
description: 13 pages, 3 figures, accepted for publication in ApJ Letters
Fast post processing algorithms for fault tolerant quantum computation using surface codes
Creators: name: Zaribafiyan, Arman
Publisher: name: University of British Columbia
Year: 2014

description: Local architecture of qubits in two dimensional lattices is known as one of the candidates to run fault tolerant quantum computation with high threshold. Topological quantum error correcting codes, such as surface codes, are used to make this architecture robust against various quantum error models. In this research we present a fast, concise, operationally inexpensive and highly parallelizable decoding algorithm for surface codes without using concatenation which has a threshold range of 8.6 % to 10.5 % varying based on a parameter called OMSS. Thanks to parallelization of the proposed algorithm, the time complexity scales logarithmically in the lattice size for small OMSS. This can be compared to the work of \citep{Poulin-2010,Poulin-2010-IEEE} which has a threshold of 8 % for the bit-flip error channel within the same complexity order.
Eventos Climáticos Extremos: Conscientização, Impactos e Atores Sociais - Editorial
Creators: name: Torres, Pedro Henrique Campello
name: Campos, Thamiris Luisa de Oliveira Brandão
name: Freitas, Edmilson
Publisher: name: figshare
Year: 2021
Subjects: subject: Climate Science
subject: 50205 Environmental Management
subject: FOS: Earth and related environmental sciences
subject: 50104 Landscape Ecology
subject: Physical Geography
subject: 40607 Surface Processes

description: Trata-se do Editorial do Volume 4, número 11, da revista Diálogos Socioambientais na Macrometrópole Paulista que trata sobre Eventos Climáticos Extremos: Conscientização, Impactos e Atores Sociais.
Second harmonic generation in GaP photonic crystal waveguides
Creators: name: Rivoire, Kelley
name: Buckley, Sonia
name: Hatami, Fariba
name: Vuckovic, Jelena
Publisher: name: arXiv
Year: 2011
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We demonstrate enhanced second harmonic generation in a gallium phosphide photonic crystal waveguide with a measured external conversion efficiency of 5$\times10^{-7}$/W. Our results are promising for frequency conversion of on-chip integrated emitters having broad spectra or large inhomogeneous broadening, as well as for frequency conversion of ultrashort pulses.
description: 3 figures
Search for heavy neutral leptons in decays of $W$ bosons using a dilepton displaced vertex in $\sqrt{s}=13$ TeV $pp$ collisions with the ATLAS detector
Creators: name: ATLAS Collaboration
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: A search for a long-lived, heavy neutral lepton ($\mathcal{N}$) in 139 fb$^{-1}$ of $\sqrt{s}=13$ TeV $pp$ collision data collected by the ATLAS detector at the Large Hadron Collider is reported. The $\mathcal{N}$ is produced via $W \rightarrow \mathcal{N} μ$ or $W \rightarrow \mathcal{N} e$ and decays into two charged leptons and a neutrino, forming a displaced vertex. The $\mathcal{N}$ mass is used to discriminate between signal and background. No signal is observed, and limits are set on the squared mixing parameters of the $\mathcal{N}$ with the left-handed neutrino states for the $\mathcal{N}$ mass range $3$ GeV $< m_{\mathcal{N}} < 15$ GeV. For the first time, limits are given for both single-flavor and multiflavor mixing scenarios motivated by neutrino flavor oscillation results for both the normal and inverted neutrino-mass hierarchies.
description: 21 pages in total 14 figures, 1 tables, submitted to Phys. Rev. Lett. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2019-29/
Spatial Inhomogeneity in RFeAsO1-xFx (R =Pr, Nd) Determined from Rare Earth Crystal Field Excitations
Creators: name: Goremychkin, E. A.
name: Osborn, R.
name: Wang, C. H.
name: Lumsden, M. D.
name: McGuire, M. A.
name: Sefat, A. S.
name: Sales, B. C.
name: Mandrus, D.
name: Rønnow, H. M.
name: Su, Y.
name: Christianson, A. D.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We report inelastic neutron scattering measurements of crystal field transitions in PrFeAsO, PrFeAsO0.87F0.13, and NdFeAsO0.85F0.15. Doping with fluorine produces additional crystal field excitations, providing evidence that there are two distinct charge environments around the rare earth ions, with probabilities that are consistent with a random distribution of dopants on the oxygen sites. The 4f electrons of the Pr3+ and Nd3+ ions have non-magnetic and magnetic ground states, respectively, indicating that the enhancement of Tc compared to LaFeAsO1-xFx is not due to rare earth magnetism.
description: 4 pages 4 figures
Rich phase transitions in step skew-products
Creators: name: Díaz, Lorenzo J.
name: Gelfert, Katrin
name: Rams, Michał
Publisher: name: arXiv
Year: 2011
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 37D35, 37D25, 37E05, 37D30, 37C29

description: We present examples of partially hyperbolic and topologically transitive local diffeomorphisms defined as skew products over a horseshoe which exhibit rich phase transitions for the topological pressure. This phase transition follows from a gap in the spectrum of the central Lyapunov exponents. It is associated to the coexistence of two equilibrium states with positive entropy. The diffeomorphisms mix hyperbolic behavior of different types. However, in some sense the expanding behavior is not dominating which is indicated by the existence of a measure of maximal entropy with nonpositive central exponent.
description: 24 pages, 4 figures
Staff and students' perceptions and acceptance of an e-learning management system at a distance education institution
Creators: name: Chokwe, Jack Matlou
Publisher: name: University of Leicester
Year: 2022
Subjects: Uncategorized

description: The study investigated the perceptions the acceptance and continued use of e-LMS for teaching and learning in South African ODeL university. A quantitative research method using a cross-sectional design was deemed appropriate to collect data that answered the research questions of this study. Two questionnaires were designed to be completed by both academic staff and first year students of a language department. The Unified Theory of Acceptance and Use of Technology (UTAUT) was adopted as the theoretical framework underpinning this study while Bourdieu’s concept of habitus, capital and field and constructivism were used as philosophical underpinnings. The findings of this study clearly indicate that despite e-learning being in its infancy in this ODeL university and South Africa in general, students and academic staff are already using the e-LMS for learning and teaching respectively. However, facilitating conditions and technological habitus which include e-LMS system overload, poor bandwidth, high data costs, minimal participation of both academic staff and students, among others, still bedevil the implementation of e-learning within the South African ODeL context. Structural equation modelling was also used to test UTAUT constructs and found that all constructs had no relationship with behavioural intention. However, age, experience and computer access were moderating variables. The findings of the study contribute to the body of knowledge on the use of UTAUT in the South African ODeL context. More importantly, the study contributes a framework for acceptance and continued use of e-LMS for ODL universities in the context of developing countries.
Topological Data Analysis for Multivariate Time Series Data
Creators: name: Bourakna, Anass El Yaagoubi
name: Chung, Moo K.
name: Ombao, Hernando
Publisher: name: arXiv
Year: 2022
Subjects: subject: Methodology (stat.ME)
subject: Neurons and Cognition (q-bio.NC)
subject: FOS: Computer and information sciences
subject: FOS: Biological sciences

description: Over the last two decades, topological data analysis (TDA) has emerged as a very powerful data analytic approach which can deal with various data modalities of varying complexities. One of the most commonly used tools in TDA is persistent homology (PH) which can extract topological properties from data at various scales. Our aim in this article is to introduce TDA concepts to a statistical audience and provide an approach to analyze multivariate time series data. The application focus will be on multivariate brain signals and brain connectivity networks. Finally, the paper concludes with an overview of some open problems and potential application of TDA to modeling directionality in a brain network as well as the casting of TDA in the context of mixed effects models to capture variations in the topological properties of data collected from multiple subjects
Decoding Senecan innovation to tragic genre tropes through anagrams, the failure of passion-restraint, and a broken play
Creators: name: Brady, Christian
Publisher: name: University of British Columbia
Year: 2014

description: This thesis shows how changes to conventional tragic structure and stories—like the number of acts, the victor of the passion-restraint scene, or the characters’ foreknowledge about future actions in the play—affects the play’s content, influence outcomes, and shape characters’ worldviews. In Hercules Furens, I examine how the Caesars’ darling hero Hercules manages to upset the tragic plot in two ways: by failing to properly express his motivations for falling into madness (in other plays explained explicitly by god characters) and failing to die honorably in just self-punishment. The play profiles a hero with divine lineage, whose power is suddenly rendered questionable by a coup in Thebes, and a town full of people who are similarly skeptical about the extent of their hero’s powers. Phaedra, in contrast, turns the lens away from the deeds of the hero and to the collateral damage wrought against the family in the process. The dissolution of the house of Theseus and the transmogrification of Phaedra into an incestuous, adulterous mother, are prompted by the Nurse’s hyperconscious remarks about the barriers to bad behavior. The Nurse ultimately undermines her own advice and instructs Phaedra on how to get away with crimes without being held morally accountable. Phoenissae’s multiple stylistic idiosyncrasies signal a unified artistic vision that Tarrant implies is diluted through the process of adaptation in the other Senecan tragedies. In this play, characters’ heightened knowledge about their future allows them to formulate advice for their children with a high degree of ironic self-referentiality. The conclusions reached by the two parents, Jocasta and Oedipus, of children at war contrasts violently with one another, although they agree on the fundamental truths of the tragic blueprint for their lives. What unites the three plays discussed throughout this thesis is the heightened level of consciousness that characters have about their own stories and the dramatic tropes of telling their story, and further, the ultimately skeptical conclusions that are implied by these unifying principles: the failure of reason to contain passion, the impotence of the world-conqueror, the tragic inevitability of fratricidal war.
Additional file 5 of Overexpression of SLC6A1 associates with drug resistance and poor prognosis in prostate cancer
Creators: name: Chen, Chaojiang
name: Cai, Zhiduan
name: Zhuo, Yangjia
name: Xi, Ming
name: Lin, Zhuoyuan
name: Jiang, Funeng
name: Liu, Zezhen
name: Wan, Yueping
name: Zheng, Yu
name: Li, Jianxin
name: Zhou, Xing
name: Zhu, Jianguo
name: Zhong, Weide
Publisher: name: figshare
Year: 2020
Subjects: subject: Biochemistry
subject: Space Science
subject: Medicine
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Pharmacology
subject: Biological Sciences not elsewhere classified
subject: Cancer
subject: Hematology

description: Additional file 5.
A Translation of "Classification of four-vectors of an 8-dimensional space," by Antonyan, L. V. , with an appendix by the translator
Creators: name: Oeding, Luke
Publisher: name: arXiv
Year: 2022
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 15A72, 17B45, 20G05

description: We give a translation of the article by L. V. Antonyan, "Classification of four-vectors of an eight-dimensional space," Trudy Sem. Vektor. Tenzor. Anal. 20 (1981), 144-161. MR622013. We include an appendix providing normal forms for each nilpotent orbit.
description: Added Hasse diagram for the orbit closures of the nilpotent orbits, and gave normal forms for all 94 nilpotent orbits. v3 corrected minor typos
Globally trace-positive noncommutative polynomials and the unbounded tracial moment problem
Creators: name: Klep, Igor
name: Scheiderer, Claus
name: Volčič, Jurij
Publisher: name: arXiv
Year: 2022
Subjects: subject: Operator Algebras (math.OA)
subject: Mathematical Physics (math-ph)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: A noncommutative (nc) polynomial is called (globally) trace-positive if its evaluation at any tuple of operators in a tracial von Neumann algebra has nonnegative trace. Such polynomials emerge as trace inequalities in several matrix or operator variables, and are widespread in mathematics and physics. This paper delivers the first Positivstellensatz for global trace positivity of nc polynomials. Analogously to Hilbert's 17th problem in real algebraic geometry, trace-positive nc polynomials are shown to be weakly sums of hermitian squares and commutators of regular nc rational functions. In two variables, this result is strengthened further using a new sum-of-squares certificate with concrete univariate denominators for nonnegative bivariate polynomials. The trace positivity certificates in this paper are obtained by convex duality through solving the so-called unbounded tracial moment problem, which arises from noncommutative integration theory and free probability. Given a linear functional on nc polynomials, the tracial moment problem asks whether it is a joint distribution of integral operators affiliated with a tracial von Neumann algebra. A counterpart to Haviland's theorem on solvability of the tracial moment problem is established. Moreover, a variant of Carleman's condition is shown to guarantee the existence of a solution to the tracial moment problem. Together with semidefinite optimization, this is then used to prove that every trace-positive nc polynomial admits an explicit approximation in the 1-norm on its coefficients by sums of hermitian squares and commutators of nc polynomials.
Non-adiabatic transitions in a non-symmetric optical lattice
Creators: name: Morales-Molina, L.
name: Reyes, S. A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We study Landau-Zener interband transitions for a non-symmetric optical lattice in the presence of an external force. We show that gain and losses of the light beam, as well as the relative occupation probabilities of the bands involved in the transitions can be accurately managed upon tuning the amplitude of the non-Hermitian component of the lattice. Exact expressions for the transition and non-transition probabilities for a non-symmetric system obtained within a two-mode approximation are provided. These equations successfully account for the main features of the transitions in the optical lattice. We also interpret the non-conventional Bloch oscillations at criticality studied in Phys. Rev. Lett. 103, 123601 (2009) as a series of a Landau-Zener transitions.
description: 6 pages, 5 figures
Code for Mercury instability AI project
Creators: name: Laurence-Chasen, J.D.
Publisher: name: University of Chicago
Year: 2023
Subjects: subject: AI
subject: Artificial Intelligence
subject: ML
subject: Machine Learning

description: This is the code used to produce an Artificial Intelligence (AI)
supervised learning Mercury instability classifier problem on the Solar System simulations of Abbot et al. (2023).
Harmonic distortion analysis of a 200-MW notional solar farm using IEEE standard 519-2014
Creators: name: Kulkarni, Aaditya Sunil
name: 0000-0001-7849-4766
Publisher: name: The University of Texas at Austin
Year: 2021
Subjects: Harmonics
Harmonic distortion analysis
Solar farm
IEEE 519
Quasi-static time series simulation
Modeling

description: Solar farms are highly concentrated photovoltaic generation units located at the utility level. In this study, the impacts of harmonic distortions of a 200-MW notional solar farm were studied. A point of common coupling (PCC) is a common interface point between the utility and solar farm. Inverters are the primary component in solar farms injecting harmonic currents at PCC. The level of distortion is affected by various weather conditions. This study primarily investigated irradiation impacts due to cloud coverage on the harmonic distortion. These variations were classified as a clear, cloudy, and very cloudy week for analysis. A clear week means all clear days, a cloudy week means all cloudy days with good irradiance, and a very cloudy week means all cloudy days with low irradiance. IEEE standard 519-2014 version was used to analyze this impact by solar farms on the main grid. This standard requires conducting studies with stochastic nature of harmonic distortion, over at least one week, with different limits for various data percentiles. A 200-MW notional solar farm inspired by real solar farms worldwide was modeled in OpenDSS. Inverters were modeled as current sources, injecting currents into transformers followed by collector circuits. Current injected by PV source was calculated from solar irradiation using an interpolation algorithm. Time-series simulations were performed using Python, with communication between OpenDSS and Python to analyze the impacts by the solar farm over a period. A simulation environment in Python was set up to perform the required functions for this study. Observations reveal the dependency of distortion on irradiation and cloud cover. An increase in cloud cover means a reduction in irradiance. Validation of results was performed using few scenarios. Violations are defined as increases of voltage or current beyond the level specified by the standard. Odd order harmonics made voltage violations. Current violations were made by even order harmonics only. Inverters were observed to inject a high proportion of harmonic current at lower irradiance. In conclusion, the studied 200-MW notional solar farm was observed to cause violations in a grid, with the nature of violations depending on irradiation and cloud cover
Inducing braces and Hopf Galois structures
Creators: name: Crespo, Teresa
name: Gil-Muñoz, Daniel
name: Rio, Anna
name: Vela, Montserrat
Publisher: name: arXiv
Year: 2022
Subjects: subject: Number Theory (math.NT)
subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: Primary: 16T05, 16T25, 12F10, Secondary: 20B35, 20B05, 20D20, 20D45

description: Let $p$ be a prime number and let $n$ be an integer not divisible by $p$ and such that every group of order $np$ has a normal subgroup of order $p$. (This holds in particular for $p>n$.) We prove that left braces of size $np$ may be obtained as a semidirect product of the unique left brace of size $p$ and a left brace of size $n$. We give a method to determine all braces of size $np$ from the braces of size $n$ and certain classes of morphisms from the multiplicative group of these braces of size $n$ to $\mathrm{Z}_p^*$. From it we derive a formula giving the number of Hopf Galois structures of abelian type $\mathrm{Z}_p \times E$ on a Galois extension of degree $np$ in terms of the number of Hopf Galois structures of abelian type $E$ on a Galois extension of degree $n$. For a prime number $p\geq 7$, we apply the obtained results to describe all left braces of size $12p$ and determine the number of Hopf Galois structures of abelian type on a Galois extension of degree $12p$.
description: arXiv admin note: text overlap with arXiv:2205.04201
Graphene-based quantum Hall interferometer with self-aligned side gates
Creators: name: Zhao, Lingfei
name: Arnault, Ethan G.
name: Larson, Trevyn F. Q.
name: Iftikhar, Zubair
name: Seredinski, Andrew
name: Fleming, Tate
name: Watanabe, Kenji
name: Taniguchi, Takashi
name: Amet, Francois
name: Finkelstein, Gleb
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The vanishing band gap of graphene has long presented challenges for making high-quality quantum point contacts (QPCs) -- the partially transparent p-n interfaces introduced by conventional split-gates tend to short the QPC. This complication has hindered the fabrication of graphene quantum Hall Fabry-Pérot interferometers, until recent advances have allowed split-gate QPCs to operate utilizing the highly resistive $ν=0$ state. Here, we present a simple recipe to fabricate QPCs by etching a narrow trench in the graphene sheet to separate the conducting channel from self-aligned graphene side gates. We demonstrate operation of the individual QPCs in the quantum Hall regime, and further utilize these QPCs to create and study a quantum Hall interferometer.
Rum, tobacco, dance, and music : the Cuban mulata in twentieth-century cinema of the Americas
Creators: name: Penate, Cary
Publisher: name: The University of Texas at Austin
Year: 2021
Subjects: Mulata
Afro-Cuban music
Cuban film music
Cuban zarzuela
Cuban teatro bufo

description: In this dissertation I examine the mulata (a mixed-race woman of black, white, and sometimes indigenous heritage) and other Latina figures who perform Afro-Cuban music in films of the 1930s, 1940s, and 1950s. Particularly, I address films from Cuba, the US, and Mexico that depict Cuban characters or incorporate Cuban musical styles. My research investigates the ways that the mulata is represented through the music, narratives, and imagery in cinematic productions leading to definitions of cubanidad throughout the Americas. I also consider the influence of the comic theater, zarzuela, and opera on film, as they shed light on the emergence of the mulata’s persona. Critical examinations of the staged mulata character type are valuable in that they document ongoing post-colonial struggles with racial inequality and ideological bias. By extension, the varied national contexts and investigations across the media and genre that I pursue underscore the marginal status of women (and in some cases their attempts to challenge the social order) in dramatic representations throughout history. Such representations suggest how national governments and multinational media have exploited the mulata and Afrodescendant music and dance for economic or political gain.
Tests of Modified Gravity with Dwarf Galaxies
Creators: name: Jain, Bhuvnesh
name: Vanderplas, Jake
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: In modified gravity theories that seek to explain cosmic acceleration, dwarf galaxies in low density environments can be subject to enhanced forces. The class of scalar-tensor theories, which includes f(R) gravity, predict such a force enhancement (massive galaxies like the Milky Way can evade it through a screening mechanism that protects the interior of the galaxy from this "fifth" force). We study observable deviations from GR in the disks of late-type dwarf galaxies moving under gravity. The fifth-force acts on the dark matter and HI gas disk, but not on the stellar disk owing to the self-screening of main sequence stars. We find four distinct observable effects in such disk galaxies: 1. A displacement of the stellar disk from the HI disk. 2. Warping of the stellar disk along the direction of the external force. 3. Enhancement of the rotation curve measured from the HI gas compared to that of the stellar disk. 4. Asymmetry in the rotation curve of the stellar disk. We estimate that the spatial effects can be up to 1 kpc and the rotation velocity effects about 10 km/s in infalling dwarf galaxies. Such deviations are measurable: we expect that with a careful analysis of a sample of nearby dwarf galaxies one can improve astrophysical constraints on gravity theories by over three orders of magnitude, and even solar system constraints by one order of magnitude. Thus effective tests of gravity along the lines suggested by Hui et al (2009) and Jain (2011) can be carried out with low-redshift galaxies, though care must be exercised in understanding possible complications from astrophysical effects.
description: 26 pages, 9 figures
Pulling and Pushing a Cargo With a Catalytically Active Carrier
Creators: name: Popescu, M. N.
name: Tasinkevych, M.
name: Dietrich, S.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: Catalytically active particles suspended in a liquid can move due to self-phoresis by generating solute gradients via chemical reactions of the solvent occurring at parts of their surface. Such particles can be used as carriers at the micro-scale. As a simple model for a carrier-cargo system we consider a catalytically active particle connected by a thin rigid rod to a catalytically inert cargo particle. We show that the velocity of the composite strongly depends on the relative orientation of the carrier-cargo link. Accordingly, there is an optimal configuration for the linkage. The subtlety of such carriers is underscored by the observation that a spherical particle completely covered by catalyst, which is motionless when isolated, acts as a carrier once attached to a cargo.
description: 6 pages, 2 figures, to appear in EPL (https://www.epletters.net/)
Modern architecture of African countries
Creators: name: Apeh Stanley Okwudily
Publisher: name: Эпоха науки
Year: 2018
Subjects: independence
steel
concrete
brick
clay
multi-storey buildings
construction industry
reconstruction
improvement

description: The article reveals the issues of architecture of African states after independence, associated with the peculiarities of climate, economy, culture. Particular attention is paid to the assistance of the Soviet Union in the construction of cities, universities, workers' settlements.
Implementing two-qubit gates at the quantum speed limit
Creators: name: Howard, Joel
name: Lidiak, Alexander
name: Jameson, Casey
name: Basyildiz, Bora
name: Clark, Kyle
name: Zhao, Tongyu
name: Bal, Mustafa
name: Long, Junling
name: Pappas, David P.
name: Singh, Meenakshi
name: Gong, Zhexuan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The speed of elementary quantum gates, particularly two-qubit gates, ultimately sets the limit on the speed at which quantum circuits can operate. In this work, we experimentally demonstrate commonly used two-qubit gates at nearly the fastest possible speed allowed by the physical interaction strength between two superconducting transmon qubits. We achieve this quantum speed limit by implementing experimental gates designed using a machine learning inspired optimal control method. Importantly, our method only requires the single-qubit drive strength to be moderately larger than the interaction strength to achieve an arbitrary two-qubit gate close to its analytical speed limit with high fidelity. Thus, the method is applicable to a variety of platforms including those with comparable single-qubit and two-qubit gate speeds, or those with always-on interactions. We expect our method to offer significant speedups for non-native two-qubit gates that are typically achieved with a long sequence of single-qubit and native two-qubit gates.
description: 11 pages, 9 figures, accepted version
The image of polynomials and Waring type problems on upper triangular matrix algebras
Creators: name: Panja, Saikat
name: Prasad, Sachchidanand
Publisher: name: arXiv
Year: 2022
Subjects: subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 16S50, 15A54

description: Let $p$ be a polynomial in non-commutative variables $x_1,x_2,\ldots,x_n$ with constant term zero over an algebraically closed field $K$. The object of study in this paper is the image of this kind of polynomial over the algebra of upper triangular matrices $T_m(K)$. We introduce a family of polynomials called multi-index $p$-inductive polynomials for a given polynomial $p$. Using this family we will show that, if $p$ is a polynomial identity of $T_t(K)$ but not of $T_{t+1}(K)$, then $p \left(T_m(K)\right)\subseteq T_m(K)^{(t-1)}$. Equality is achieved in the case $t=1,~m-1$ and an example has been provided to show that equality does not hold in general. We further prove existence of $d$ such that each element of $T_m(K)^{(t-1)}$ can be written as sum of $d$ many elements of $p\left( T_m(K) \right)$. It has also been shown that the image of $T_m(K)^\times$ under a word map is Zariski dense in $T_m(K)^\times$.
description: 39 pages, 6 figures, and comments are welcome; Waring type problem is modified
The overdensity and masses of the friends-of-friends halos and universality of the halo mass function
Creators: name: More, Surhud
name: Kravtsov, Andrey
name: Dalal, Neal
name: Gottlöber, Stefan
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The friends-of-friends algorithm (hereafter, FOF) is a percolation algorithm which is routinely used to identify dark matter halos from N-body simulations. We use results from percolation theory to show that the boundary of FOF halos does not correspond to a single density threshold but to a range of densities close to a critical value that depends upon the linking length parameter, b. We show that for the commonly used choice of b = 0.2, this critical density is equal to 81.62 times the mean matter density. Consequently, halos identified by the FOF algorithm enclose an average overdensity which depends on their density profile (concentration) and therefore changes with halo mass contrary to the popular belief that the average overdensity is ~180. We derive an analytical expression for the overdensity as a function of the linking length parameter b and the concentration of the halo. Results of tests carried out using simulated and actual FOF halos identified in cosmological simulations show excellent agreement with our analytical prediction. We also find that the mass of the halo that the FOF algorithm selects crucially depends upon mass resolution. We find a percolation theory motivated formula that is able to accurately correct for the dependence on number of particles for the mock realizations of spherical and triaxial Navarro-Frenk-White halos. However, we show that this correction breaks down when applied to the real cosmological FOF halos due to presence of substructures. Given that abundance of substructure depends on redshift and cosmology, we expect that the resolution effects due to substructure on the FOF mass and halo mass function will also depend on redshift and cosmology and will be difficult to correct for in general. Finally, we discuss the implications of our results for the universality of the mass function.
description: 19 pages, 17 figures, submitted to ApJ supplement
Using modified intention-to-treat as a principal stratum estimator for failure to initiate treatment
Creators: name: Kahan, Brennan C
name: White, Ian R
name: Edwards, Mark
name: Harhay, Michael O
Publisher: name: arXiv
Year: 2022
Subjects: subject: Methodology (stat.ME)
subject: FOS: Computer and information sciences

description: Background: A common intercurrent event affecting many trials is when some participants do not begin their assigned treatment. Many trials use a modified intention-to-treat (mITT) approach, whereby participants who do not initiate treatment are excluded from the analysis. However, it is not clear the estimand being targeted by such an approach or the assumptions necessary for it to be unbiased. Methods: We demonstrate that a mITT analysis which excludes participants who do not begin treatment is estimating a principal stratum estimand (i.e. the treatment effect in the subpopulation of participants who would begin treatment, regardless of which arm they were assigned to). The mITT estimator is unbiased for the principal stratum estimand under the assumption that the intercurrent event is not affected by the assigned treatment arm, that is, participants who initiate treatment in one arm would also do so in the other arm. Results: We identify two key criteria in determining whether the mITT estimator is likely to be unbiased: first, we must be able to measure the participants in each treatment arm who experience the intercurrent event, and second, the assumption that treatment allocation will not affect whether the participant begins treatment must be reasonable. Most double-blind trials will satisfy these criteria, and we provide an example of an open-label trial where these criteria are likely to be satisfied as well. Conclusions: A modified intention-to-treat analysis which excludes participants who do not begin treatment can be an unbiased estimator for the principal stratum estimand. Our framework can help identify when the assumptions for unbiasedness are likely to hold, and thus whether modified intention-to-treat is appropriate or not.
description: Changes to Introduction and Abstract, minor changes to Methods
A new method for estimating frequency-dependent core shifts in active galactic nucleus jets
Creators: name: Kudryavtseva, N. A.
name: Gabuzda, D. C.
name: Aller, M. F.
name: Aller, H. D.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We discuss the opacity in the core regions of active galactic nuclei observed with Very Long Baseline Interferometry (VLBI), and describe a new method for deriving the frequency-dependent shifts of the VLBI core from the frequency-dependent time lags of flares observed with single-dish observations. Application of the method to the core shifts of the quasar 3C 345 shows a very good agreement between the core shifts directly measured from VLBI observations and derived from flares in the total flux density using the proposed method. The frequency-dependent time lags of flares can be used to derive physical parameters of the jets, such as distance from the VLBI core to the base of the jet and the magnetic fields in the core region. Our estimates for 3C 345 indicate core magnetic fields ~0.1 G and magnetic field at 1 pc ~0.4 G.
description: 8 pages, 6 figures, accepted for publication in MNRAS
Optical Properties of Chiral Three-Dimensional Photonic Crystals made from Semiconductors
Creators: name: Takahashi, Shun
name: Tajiri, Takeyoshi
name: Arakawa, Yasuhiko
name: Iwamoto, Satoshi
name: Vos, Willem L.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We perform a theoretical and numerical study of the optical properties of both direct and inverse three-dimensional (3D) chiral woodpile structures, and a corresponding chiral Bragg stack. We compute transmission spectra in the helical direction for finite crystals, and photonic band structures, where we ensure the effective index of all structures to be the same. We find that both 3D structures show dual-band circular dichroism, where light with a particular circular polarization state - either left- or right-handed - reveals a broad stop band with major attenuation, whereas the other polarization state is transmitted nearly unimpeded. We observe such gaps in different frequency ranges, with alternating handedness. The appearance of the circular-polarized gaps is successfully interpreted with a physical model wherein the circular polarization either co-rotates or counter-rotates with the chiral structure, thereby effectively leading to a spatially-dependent or a constant refractive index, and thus to the presence or absence of a gap. We find that the presence or absence of circularly polarized gaps is tuned by the transverse periods perpendicular to the chiral axis in both the 3D direct and inverse chiral woodpile crystal structures. The tunability of circular dichroism may find applications as on-chip sensors for circularly polarized light and in the on-chip detection of chiral molecules.
description: 10 pages, 9 figures
DEP Bulletin:Volume 39 Issue 7
Creators: name: No Name Supplied
Publisher: name: No Publisher Supplied
Year: 2015

description: The DEP bulletin is a semi-monthly publication of the New Jersey Department of Environmental Protection. It contains a list of construction permit applications recently filed or acted upon by the Department along with a calendar of events of interest, a schedule of public hearings, and Environmental Impact Statements acted upon during the period.
The trouble with neurodiversity : etiologies, normativity, and the autistic struggle for identity
Creators: name: Garen, Josef
Publisher: name: University of British Columbia
Year: 2014

description: Scientific research into the etiology of autism has lead to an explosion in proposed agents implicated in the development of autism over the past 70 years. Genetics, neurotoxins, vaccinations, viral infections, parenting practices, neurological abnormalities, among others, have been proposed to explain what increasingly appears to be a heterogeneous and overdetermined condition. These proposed etiologies and the treatments they suggest pose a peculiar problem for the neurodiversity movement, an activist group of autistics and nonautistics who hope to promote a positive understanding of autism. In broad terms, the neurodiversity movement opposes cure-oriented research and activism typical of the scientific community and mainstream autism advocacy organizations. They hope to counter this trend by promoting autism as a positive identity – a normal human variation, rather than a pathology. The tension between these two modes of thought provides a rich terrain for exploring the possibilities of identity formation even as human behaviour increasingly falls under the rubric of medical science. The scientific research discussed in this thesis simultaneously constructs and is constructed by an understanding of autism as a pathology, and in so doing challenges the claims of the neurodiversity movement both directly and indirectly: reproductive technologies and proposed treatments for autism force parents to make judgements about the worth of autistic persons, for example. This thesis draws on literature from bioethics, philosophy of medicine, and disability studies to situate both the neurodiversity movement and the scientific community in debates about normality, normativity, suffering, and the nature of disease. I argue that while the neurodiversity movement's emphasis on normality is ultimately misplaced, the movement nevertheless has much to teach us about rights, identity, authority, and self-determination.
SGR 1806-20 distance and dust properties in molecular clouds by analysis of a flare x-ray echoes
Creators: name: Svirski, Gilad
name: Nakar, Ehud
name: Ofek, Eran O.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The soft gamma repeater SGR 1806-20 is most famous for its giant flare from 2004, which yielded the highest gamma-ray flux ever observed on Earth. The flare emphasized the importance of determining the distance to the SGR, thus revealing the flare's energy output, with implications on SGRs energy budget and giant flare rates. We analyze x-ray scattering echoes observed by Swift/XRT following the 2006 August 6 intermediate burst of SGR 1806-20. Assuming positions and opacities of the molecular clouds along the line-of-sight from previous works, we derive direct constrains on the distance to SGR 1806-20, setting a lower limit of 9.4 kpc and an upper limit of 18.6 kpc (90% confidence), compared with a 6-15 kpc distance range by previous works. This distance range matches an energy output of ~10^46 erg/s for the 2004 giant flare. We further use, for the first time, the x-ray echoes in order to study the dust properties in molecular clouds. Analyzing the temporal evolution of the observed flux using a dust scattering model, which assumes a power-law size distribution of the dust grains, we find a power-law index of -3.3_{-0.7}^{+0.6} (1 sigma) and a lower limit of 0.1 micron (2 sigma) on the dust maximal grain size, both conforming to measured dust properties in the diffused interstellar medium (ISM). We advocate future burst follow-up observations with Swift, Chandra and the planned NuSTAR telescopes, as means of obtaining much superior results from such an analysis.
description: 12 pages, 7 figures, 3 tables, submitted to MNRAS
Development of high-frequency magnetic probe for plasma diagnostics of XuanLong-50
Creators: name: Wang, Mingyuan
name: Lun, Xiuchun
name: Bo, Xiaokun
name: Liu, Bing
name: Liu, Adi
name: Shi, Yuejiang
Publisher: name: arXiv
Year: 2022
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: A high-frequency magnetic probe has been designed and developed on XuanLong-50 (EXL-50) spherical torus to measure high-frequency magnetic field fluctuations caused by energetic ions and electrons in the plasma. The magnetic loop, radio filters, radio-frequency (RF) limiter, and data acquisition system of the probe are described in detail. The results of the preliminary test show that the probe can have a frequency response within the 1- 180 MHz range. The fluctuation data from the EXL-50 plasma were analyzed in the time-frequency domain using fast Fourier transforms. Using this diagnostic system, distinct high-frequency instabilities were detected. In particular, significant frequency chirping was observed, which is consistent with the bump on tail drive instability predicted by the Berk-Breizman model.
HST/STIS Lyman-alpha observations of the quiet M dwarf GJ436: Predictions for the exospheric transit signature of the hot neptune GJ436b
Creators: name: Ehrenreich, David
name: Etangs, Alain Lecavelier des
name: Delfosse, Xavier
Publisher: name: arXiv
Year: 2011
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Lyman-alpha (Lya) emission of neutral hydrogen (1215.67 Angström) is the main contributor to the ultraviolet flux of low-mass stars such as M dwarfs. It is also the main light source used in studies of the evaporating upper atmospheres of transiting extrasolar planets with ultraviolet transmission spectroscopy. However, there are very few observations of the Lya emissions of quiet M dwarfs, and none exist for those hosting exoplanets. Here, we present Lya observations of the hot-neptune host star GJ436 with the Hubble Space Telescope Imaging Spectrograph (HST/STIS). We detect bright emission in the first resolved and high quality spectrum of a quiet M dwarf at Lya. Using an energy diagram for exoplanets and an N-body particle simulation, this detection enables the possible exospheric signature of the hot neptune to be estimated as a ~11% absorption in the Lya stellar emission, for a typical mass-loss rate of 10^10 g/s. The atmosphere of the planet GJ436b is found to be stable to evaporation, and should be readily observable with HST. We also derive a correlation between X-ray and Lya emissions for M dwarfs. This correlation will be useful for predicting the evaporation signatures of planets transiting other quiet M dwarfs.
description: 8 pages, 8 figures, 2 tables. Accepted for publication in Astronomy & Astrophysics