cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Electric field of a pointlike charge in a strong magnetic field and ground state of a hydrogenlike atom
Creators: name: Shabad, A. E.
name: Usov, V. V.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: In an external constant magnetic field, so strong that the electron Larmour length is much shorter than its Compton length, we consider the modification of the Coulomb potential of a point charge owing to the vacuum polarization. We establish a short-range component of the static interaction in the Larmour scale, expressed as a Yukawa-like law, and reveal the corresponding "photon mass" parameter. The electrostatic force regains its long-range character in the Compton scale: the tail of the potential follows an anisotropic Coulomb law, decreasing away from the charge slower along the magnetic field and faster across. In the infinite-magnetic-field limit the potential is confined to an infinitely thin string passing though the charge parallel to the external field. This is the first evidence for dimensional reduction in the photon sector of quantum electrodynamics. The one-dimensional form of the potential on the string is derived that includes a delta-function centered in the charge. The nonrelativistic ground-state energy of a hydrogenlike atom is found with its use and shown not to be infinite in the infinite-field limit, contrary to what was commonly accepted before, when the vacuum polarization had been ignored. These results may be useful for studying properties of matter at the surface of extremely magnetized neutron stars.
description: 45 pages, 6 figures, accepted to Phys. Rev. D
Eigenfunctions of the two-dimensional Moshinsky-Szczepaniak Oscillator
Creators: name: Rao, Nagalakshmi A.
name: Kagali, B. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: While the usual harmonic oscillator potential gives discrete energies in the non-relativistic case, it does not however give genuine bound states in the relativistic case if the potential is treated in the usual way. In the present article, we have obtained the eigenfunctions of the Dirac oscillator in two spatial dimensions, adapting the prescription of Moshinsky.
description: Latex, 8 Pages, No Figures
ALMA uncovers optically thin and multi-component CO gas in the outflowing circumnuclear disk of NGC1068 (aa53704-25; Appendix D-G)
Creators: name: Zhang, Yuze
name: Viti, Serena
name: Garcia-Burillo, Santiago
name: Huang, Ko-Yun
Publisher: name: Zenodo
Year: 2025
Subjects: subject: Astronomy

description: This document contains appendices D-G of the A&A publication ALMA uncovers optically thin and multi-component CO gas in the outflowing circumnuclear disk of NGC1068 (aa53704-25).
An Optical physics inspired CNN approach for intrinsic image decomposition
Creators: name: Weligampola, Harshana
name: Jayatilaka, Gihan
name: Sritharan, Suren
name: Ekanayake, Parakrama
name: Ragel, Roshan
name: Herath, Vijitha
name: Godaliyadda, Roshan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Intrinsic Image Decomposition is an open problem of generating the constituents of an image. Generating reflectance and shading from a single image is a challenging task specifically when there is no ground truth. There is a lack of unsupervised learning approaches for decomposing an image into reflectance and shading using a single image. We propose a neural network architecture capable of this decomposition using physics-based parameters derived from the image. Through experimental results, we show that (a) the proposed methodology outperforms the existing deep learning-based IID techniques and (b) the derived parameters improve the efficacy significantly. We conclude with a closer analysis of the results (numerical and example images) showing several avenues for improvement.
description: 5 pages, 3 figures, 1 table, ICIP 2021
Slow Momentum with Fast Reversion: A Trading Strategy Using Deep Learning and Changepoint Detection
Creators: name: Wood, Kieran
name: Roberts, Stephen
name: Zohren, Stefan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: Trading and Market Microstructure (q-fin.TR)
subject: FOS: Computer and information sciences
subject: FOS: Economics and business

description: Momentum strategies are an important part of alternative investments and are at the heart of commodity trading advisors (CTAs). These strategies have, however, been found to have difficulties adjusting to rapid changes in market conditions, such as during the 2020 market crash. In particular, immediately after momentum turning points, where a trend reverses from an uptrend (downtrend) to a downtrend (uptrend), time-series momentum (TSMOM) strategies are prone to making bad bets. To improve the response to regime change, we introduce a novel approach, where we insert an online changepoint detection (CPD) module into a Deep Momentum Network (DMN) [1904.04912] pipeline, which uses an LSTM deep-learning architecture to simultaneously learn both trend estimation and position sizing. Furthermore, our model is able to optimise the way in which it balances 1) a slow momentum strategy which exploits persisting trends, but does not overreact to localised price moves, and 2) a fast mean-reversion strategy regime by quickly flipping its position, then swapping it back again to exploit localised price moves. Our CPD module outputs a changepoint location and severity score, allowing our model to learn to respond to varying degrees of disequilibrium, or smaller and more localised changepoints, in a data driven manner. Back-testing our model over the period 1995-2020, the addition of the CPD module leads to an improvement in Sharpe ratio of one-third. The module is especially beneficial in periods of significant nonstationarity, and in particular, over the most recent years tested (2015-2020) the performance boost is approximately two-thirds. This is interesting as traditional momentum strategies have been underperforming in this period.
description: minor changes made to methodology to match implementation
Spin orbit torque nano-oscillators by dipole field-localized spin wave modes
Creators: name: Zhang, Chi
name: Lee, Inhee
name: Pu, Yong
name: Manuilov, Sergei A.
name: Pelekhov, Denis V.
name: Hammel, P. Chris
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We demonstrate a high-quality spin orbit torque nano-oscillator comprised of spin wave modes confined by the magnetic field by the strongly inhomogeneous dipole field of a nearby micromagnet. This approach enables variable spatial confinement and systematic tuning of magnon spectrum and spectral separations for studying the impact of multi-mode interactions on auto-oscillations. We find these dipole field-localized spin wave modes exhibit good characteristic properties as auto-oscillators--narrow linewidth and large amplitude--while persisting up to room temperature. We find that the linewidth of the lowest-lying localized mode is approximately proportional to temperature in good agreement with theoretical analysis of the impact of thermal fluctuations. This demonstration of a clean oscillator with tunable properties provides a powerful tool for understanding the fundamental limitations and linewidth contributions to improve future spin-Hall oscillators.
description: corrected funding number, added Supplementary Information, revised manuscript
Political structures and the topology of simplicial complexes
Creators: name: Mock, Andrea
name: Volic, Ismar
Publisher: name: arXiv
Year: 2021
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Theoretical Economics (econ.TH)
subject: Combinatorics (math.CO)
subject: Dynamical Systems (math.DS)
subject: FOS: Physical sciences
subject: FOS: Economics and business
subject: FOS: Mathematics
subject: 91C99, 91F10

description: We use the topology of simplicial complexes to model political structures following [1]. Simplicial complexes are a natural tool to encode interactions in the structures since a simplex can be used to represent a subset of compatible agents. We translate the wedge, cone, and suspension operations into the language of political structures and show how these constructions correspond to merging structures and introducing mediators. We introduce the notions of the viability of an agent and the stability of a political system and examine their interplay with the simplicial complex topology, casting their interactions in category-theoretic language whenever possible. We introduce a refinement of the model by assigning weights to simplices corresponding to the number of issues the agents agree on. In addition, homology of simplicial complexes is used to detect non-viabilities, certain cycles of incompatible agents, and the (non)presence of mediators. Finally, we extend some results from [1], bringing viability and stability into the language of friendly delegations and using homology to examine the existence of R-compromises and D-compromises.
description: 30 pages
Cortical influences upon the dive response of the muskrat (Ondatra zibethica)
Creators: name: McCulloch, Paul Frederick
Publisher: name: University of British Columbia
Year: 2010

description: Force dived animals undergo cardiovascular changes characterized by bradycardia, increased total peripheral resistance, and changes in blood flow distribution. Since these changes occur in decerebrated animals, the dive response must be a brainstem reflex. However, in voluntary dives, animals may show anticipatory bradycardia and may also adjust their cardiovascular responses according to anticipated dive duration, indicating suprabulbar influences upon dive responses. Studies of heart rate using telemetry have shown that there can be substantial differences in the dive response of voluntarily and force dived animals. Furthermore, some animals show a "fear bradycardia" when trapped in a stressful situation, leading some researchers to suggest that bradycardia during forced submersion is an artifact of the stress of the situation. Muskrats (Ondatra zibethica) were observed freely diving for food in an indoor tank using a video camera and VCR unit. EKG was telemetered from the animals and recorded on the audio channel of the VCR tape. Heart rate responses to voluntary dives were analyzed and compared with those from escape and forced dives. Heart rate responses were also recorded from decorticate and sham operated muskrats to elucidate the role that the cerebral cortex plays in the dive response. In all types of dives, muskrats exhibited a rapid and large bradycardia upon submergence (heart rate declined by greater than 55% of the predive heart rate). Obviously diving bradycardia in the muskrat was not due to fear or stress, but occurred as a response to submersion per se. There was no evidence of post-dive tachycardia or anticipatory immersion bradycardia. Disturbing the animal in a non-diving situation resulted in only a 13% decrease in heart rate. In intact animals voluntary, escape, and forced submergence resulted in progressively greater decreases in heart rate. Heart rate fell by 56% in voluntary dives, 65% in escape dives, and 73% in forced dives. Intensification of the bradycardia to a lower heart rate than that seen in voluntary dives was mediated by the cerebral cortex, as heart rate in decorticate muskrats in escape and forced dives did not fall below that seen in voluntary dives. This indicates that the final adjustment of dive heart rate is dependent upon an intact cerebral cortex. However, in decorticate muskrats there appeared to be a recovery of cortical function, as intensification of bradycardia in forced dives was dependent upon the time that had elapsed after surgery. This study shows that there is a cortical influence upon the cardiovascular system during diving. It also indicates that in experiments with unanesthetized animals, the degree of stress of the situation must be taken into account, as this may affect physiological responses.
Sums of products of congruence classes and of arithmetic progressions
Creators: name: Konyagin, Sergei V.
name: Nathanson, Melvyn B.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11A07, 11B25, 11B75

description: Consider the congruence class R_m(a)={a+im:i\in Z} and the infinite arithmetic progression P_m(a)={a+im:i\in N_0}. For positive integers a,b,c,d,m the sum of products set R_m(a)R_m(b)+R_m(c)R_m(d) consists of all integers of the form (a+im)(b+jm)+(c+km)(d+\ell m) for some i,j,k,\ell\in Z. It is proved that if gcd(a,b,c,d,m)=1, then R_m(a)R_m(b)+R_m(c)R_m(d) is equal to the congruence class R_m(ab+cd), and that the sum of products set P_m(a)P_m(b)+P_m(c)P_m(d) eventually coincides with the infinite arithmetic progression P_m(ab+cd).
description: 8 pages
Phase-Dependence of Resonant and Antiresonant Two-Photon Excitations
Creators: name: Drescher, Lorenz
name: Witting, Tobias
name: Kornilov, Oleg
name: Vrakking, Marc J. J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Measurements of the phase of two-photon matrix elements are presented for resonant and antiresonant two-color ionization of helium. A tunable, narrow-bandwidth, near-infrared (NIR) laser source is used for extreme ultra-violet (XUV) high-harmonic generation (HHG). The 15th harmonic of the laser is used within (1+1') XUV+NIR two-photon ionization, and tuned in and out of resonance with members of the 1s$n$p $^1$P$_1$ ($n=3,4,5$) Rydberg series, covering a broad spectral range with high spectral resolution. The technique allows to observe characteristic rapid changes in the phase of the two-photon matrix elements around the resonances and, previously unobserved, at the antiresonances between the resonances. Similar effects are observed for (1+2') XUV+NIR three-photon ionization. The experimental results are compared to a perturbative model and to numerical solutions of the time-dependent Schrödinger equation (TDSE) in the single active electron (SAE) approximation, elucidating the origin and dependences of the observed phenomena.
description: Accepted version, to be published in Physical Review A. 8 pages, 3 figures
EXPLORING SIZE AND BRYOZOAN ENCRUSTATION OVER TIME IN SOUTHERN CALIFORNIA CREPIPATELLA LINGULATA (GASTROPODA: CALYPTRAEIDAE): PLEISTOCENE TO PRESENT DAY
Creators: name: Meade, Kevin
Publisher: name: Zenodo
Year: 2021
Subjects: fossil
bryozoan
gastropod
Calyptraeidae
symbiosis
epibiont

description: This study examines the bryozoan fauna encrusting on the common Pacific half-slippersnail, Crepipatella lingulata. This suspension-feeding calyptraeid gastropod is common at shallow depths off the coast of California and is also common in the fossil record. The shell lengths of C. lingulata specimens dating back to the late Pliocene-early Pleistocene were examined, as well as the area of shells encrusted with bryozoans. Holocene shells were significantly larger than other shells, and modern (specimens collected in the present day) encrusted shells were significantly shorter than encrusted shells from the ancient past, but the latter could reflect collection bias. I also determined that modern shells are more fully covered with bryozoans than fossil shells. However, there was significant statistical interaction in the Holocene and modern data; thus, if more specimens were to be added that were relatively less prone to sampling biases from these time periods, the observed patterns could change. Finally, I identified bryozoan species encrusting on modern C. lingulata shells: 34 of the 41 specimens examined were found to be the species Rhynchozoon rostratum and, because one bryozoan species seems to dominate the encrustation, this implies a symbiotic association between C. lingulata and R. rostratum.
Dy2Ti2O7 Spin Ice: a Test Case for Emergent Clusters in a Frustrated Magnet
Creators: name: Yavors'kii, Taras
name: Fennell, Tom
name: Gingras, Michel J. P.
name: Bramwell, Steven T.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Dy2Ti2O7 is a geometrically frustrated magnetic material with a strongly correlated spin ice regime that extends from 1 K down to as low as 60 mK. The diffuse elastic neutron scattering intensities in the spin ice regime can be remarkably well described by a phenomenological model of weakly interacting hexagonal spin clusters, as invoked in other geometrically frustrated magnets. We present a highly refined microscopic theory of Dy2Ti2O7 that includes long-range dipolar and exchange interactions to third nearest neighbors and which demonstrates that the clusters are purely fictitious in this material. The seeming emergence of composite spin clusters and their associated scattering pattern is instead an indicator of fine-tuning of ancillary correlations within a strongly correlated state.
description: 4 pages, 2 figures. Conforms to published version. Small amendments compared to version #1. A high resolution version of Figure 1 can be obtained by e-mailing gingras@gandalf.uwaterloo.ca
Upper limit on spontaneous supercurrents in Sr$_2$RuO$_4$
Creators: name: Kirtley, J. R.
name: Kallin, C.
name: Hicks, C. W.
name: Kim, E. -A.
name: Liu, Y.
name: Moler, K. A.
name: Maeno, Y.
name: Nelson, K. D.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: It is widely believed that the perovskite Sr$_2$RuO$_4$ is an unconventional superconductor with broken time reversal symmetry. It has been predicted that superconductors with broken time reversal symmetry should have spontaneously generated supercurrents at edges and domain walls. We have done careful imaging of the magnetic fields above Sr$_2$RuO$_4$ single crystals using scanning Hall bar and SQUID microscopies, and see no evidence for such spontaneously generated supercurrents. We use the results from our magnetic imaging to place upper limits on the spontaneously generated supercurrents at edges and domain walls as a function of domain size. For a single domain, this upper limit is below the predicted signal by two orders of magnitude. We speculate on the causes and implications of the lack of large spontaneous supercurrents in this very interesting superconducting system.
description: 9 pages
Correlación y Causalidad Claves para una Interpretación Correcta en Investigación Cardiometabólica
Creators: name: ROJAS RODRIGUEZ, JORGE ENRIQUE
Publisher: name: Zenodo
Year: 2025

description: En la investigación médica, especialmente en enfermedades cardiometabólicas, es esencial distinguir entre correlación y causalidad. Esta diferencia impacta directamente en cómo se interpretan los hallazgos científicos y se toman decisiones clínicas
Bovine Embryo Transfer and the Veterinary Practitioner
Creators: name: Elsden, R.P.
Publisher: name: American Association of Bovine Practitioners  Proceedings of the Annual Conference
Year: 1981

description: Once embryo transfer techniques become familiar to the veterinary practitioner, embryos can be efficiently collected from four to five donors and transferred nonsurgically into recipients in less than half a day provided excellent facilities are available. However, considerable initial effort is required to learn the techniques of recovery, recognition, manipulation, and transfer of embryos. It usually takes a full year for an experienced bovine practitioner to become proficient in the technique of embryo transfer.
description: American Association of Bovine Practitioners Proceedings of the Annual Conference, 1981
Quantum Algorithms for Learning and Testing Juntas
Creators: name: Atici, Alp
name: Servedio, Rocco A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: Machine Learning (cs.LG)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: In this article we develop quantum algorithms for learning and testing juntas, i.e. Boolean functions which depend only on an unknown set of k out of n input variables. Our aim is to develop efficient algorithms: - whose sample complexity has no dependence on n, the dimension of the domain the Boolean functions are defined over; - with no access to any classical or quantum membership ("black-box") queries. Instead, our algorithms use only classical examples generated uniformly at random and fixed quantum superpositions of such classical examples; - which require only a few quantum examples but possibly many classical random examples (which are considered quite "cheap" relative to quantum examples). Our quantum algorithms are based on a subroutine FS which enables sampling according to the Fourier spectrum of f; the FS subroutine was used in earlier work of Bshouty and Jackson on quantum learning. Our results are as follows: - We give an algorithm for testing k-juntas to accuracy $ε$ that uses $O(k/ε)$ quantum examples. This improves on the number of examples used by the best known classical algorithm. - We establish the following lower bound: any FS-based k-junta testing algorithm requires $Ω(\sqrt{k})$ queries. - We give an algorithm for learning $k$-juntas to accuracy $ε$ that uses $O(ε^{-1} k\log k)$ quantum examples and $O(2^k \log(1/ε))$ random examples. We show that this learning algorithms is close to optimal by giving a related lower bound.
description: 15 pages, 1 figure. Uses synttree package. To appear in Quantum Information Processing
Effect of non-uniform efficiency on higher-order cumulants in heavy-ion collisions
Creators: name: Si, Fan
name: Zhang, Yifei
name: Luo, Xiaofeng
Publisher: name: arXiv
Year: 2021
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We perform a systematic study on the effect of non-uniform track efficiency correction in higher-order cumulant analysis in heavy-ion collisions. Through analytical derivation, we find that the true values of cumulants can be successfully reproduced by the efficiency correction with an average of the realistic detector efficiency for particles with the same charges within each single phase space. The theoretical conclusions are supported by a toy model simulation by tuning the non-uniformity of the efficiency employed in the track-by-track efficiency correction method. The valid averaged efficiency is found to suppress the statistical uncertainties of the reproduced cumulants dramatically. Thus, usage of the averaged efficiency requires a careful study of phase space dependence. This study is important for carrying out precision measurements of higher-order cumulants in heavy-ion collision experiments at present and in future.
description: 21 pages and 17 figures
title: Visualisierung: Schaffen Bilder Wissen?
Creators: name: Akademie, Die
Publisher: name: MyCoRe Community
Year: 2012
Subjects: subject: Denken
subject: Fluoreszenz
subject: Quantenbits
subject: Kernspinresonanzspektroskopie
subject: Stereotyp
subject: Migrationsforschung
subject: Bildwissenschaft
subject: Global Young Academy
subject: 000

description: „Geistiges Eigentum ist das Öl des 21. Jahrhunderts“, sagte Mark Getty, Gründer der Fotoagentur Getty Images. Die Agentur gehört längst nicht mehr ihm, er und Vorstandschef Jonathan Klein sind an der Firma beteiligt. Im August 2012 ging die Fotoagentur für 3,3 Milliarden Dollar an die US-Beteiligungsgesellschaft Carlyle. Die vorliegende Ausgabe des Junge Akademie Magazins beschäftigt sich im Dossier mit Visualisierung. Wie werden in der Wissenschaft Dinge dargestellt, die zu klein sind, um sie zu sehen? Wie konstruieren Naturwissenschaftler die Welt der Teilchen, auch aus didaktischen Gründen? Wie kombinieren sie Messdaten, um ein Bild aus dem Inneren einer Galaxie zu machen? Gibt es einen guten und einen schlechten Umgang mit Bildern, etwa in der Mediävistik? Wo liegen die Grenzen der Visualisierbarkeit, auch in der Kunst? Wie Wissenschaftler Daten visualisieren, kann ihre weitere Forschung beeinflussen, inhaltlich ebenso wie in ihrer Karriere. Visuelle Erzeugnisse – in den Medien, in der Wissenschaft, in der Kunst – sind gefragter denn je. Und zugleich stehen sie unter Druck: Im Falle der Fotoagenturen gibt seit Jahren Konkurrenz zu hochpreisigen Agenturen; sogenannte Microstockagenturen verkaufen Laienfotografien im Centbereich. Fotoagenturen sind zugleich Archive, und Archive weisen nicht immer die richtigen Quellen aus: Die Entstehungsgeschichte eines Bildes und die heutige Verwendung können dekontextualisiert sein – und somit zu falschen Schlüssen verleiten. Auch das ist ein Thema in unserem Schwerpunkt. Welche Rolle spielt schließlich die Digitalisierung dabei? Das Internet gilt als großes Archiv, doch ob nicht gerade die Gegenwartskultur und Medienkunst vom Verlust bedroht sind, fragt Oliver Grau, Alumnus der JA, in seinem Gastbeitrag. Viel Freude beim Lesen wünscht Ihnen im Namen des Redaktionsteams Evelyn Runge
description: Junge Akademie Magazin, vol. 14
Wealth and power in Yayoi Period Northern Kyushu
Creators: name: Stark, Ken
Publisher: name: University of British Columbia
Year: 2010

description: This thesis is concerned with the analysis of grave goods, from Yayoi period cemetery sites in northern Kyushu, to test for the presence of status rivalry and competition between leaders of different . communities. The study consists of a test of two major hypotheses that were derived from a model that links economic and political success of chiefs with wealth display and the mortuary ritual. Hypothesis 1 stated that status rivalry was present in the development of social ranking within communities in northern Kyushu. The key pattern in this case is that change in political authority is indicated by change in patterns of wealth distribution and display. Since there was a trend toward a lack of change in the number of separate wealth rank levels among burials, meaning a lack of change in patterns of wealth distribution, the analysis results disproved Hypothesis 1. Hypothesis 2 stated that status rivalry and competition ensured short-term political success and fluctuations in patterns of wealth distribution between sites in a regional exchange hierarchy. As a result, major structural changes occurred in the organization of the existing wealth exchange network. Since the analysis revealed that regions with the most developed hierarchy experienced the greatest upheaval and change in organizational structure, Hypothesis 2 was not disproven. Overall, the results show that structural change in wealth exchange systems occurred on a regional scale more than change in internal rank ordering and wealth control within sites. If wealth possession was an indicator of power, political control in Yayoi period northern Kyushu was of a very precarious nature.
Spixosoma mucronata Rondani 1857
Creators: name: Sforzi, Alessandra
name: Sommaggio, Daniele
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Conopidae
Spixosoma
Spixosoma mucronata

description: Spixosoma mucronata Rondani, 1857
ORIGINAL DESCRIPTION: 1857: 224 (key), 225 (description).
TYPE LOCALITY: “ in collibus subapenninis ditionis Parmensis …. In Pedemontio [Parmese sub-Apennine hills … Piedmont (Italy)]”.
TYPE MATERIAL: 3 ♂♂, 2 ♀♀, syntypes (one male and one female pinned together) (MZUF: Box 8): Sphixosoma [sic!] Rndn. / mucronata Rnd., ♂ ♀ / 378; 1 ♀, syntype (MZUF: Box B): Sphixosoma [sic!] R. mucronata R., 134, ♀, Parma / 393 134; 1 ♂, syntype (MSNC: Box DIPTERA Ex collezione Rondani - I): Spixosoma mucronata R. ♂ Parma / Coll. Rondani, scatola n° 4, posiz. E-4 / Museo di Storia Naturale Università di Pisa, Calci (PI) ex collezione Rondani; 1 ♂, syntype (MSNPV: Box 100): Sphixosoma [sic!] mucronata R., 4, Parma; 1 ♂, syntype (OUMNH Verrall-Collin Coll.: Box. 1): Type / C. mucronatus Coll. Big. / syntype / C. mucronatus ♂ id. vitellinus Loew? Schin. Europe Sphyxosoma id. Rond. / Conops; 1 ♂, syntype (OUMNH Verrall-Collin Coll. Box. 1): Rondani Typ. / Sphixosoma mucronata Rd. / sec. typ. Rondanii / C. mucronata E. Kow. / vitellinus / syntype / C. mucronatus ♂ id vitellinus Loew? Schin. Europe, Sphyxosoma id. Rond. / Conops.
CURRENT STATUS: junior synonym of Conops vitellinus Loew, 1847 (Chvála & Smith 1988: 251, Stuke 2017: 51).
REMARKS: Rondani (1857: 225) described Sphixosoma mucronata, without specifying the number, the sex or the length of the specimens, from material he had collected and also received from L. Bellardi. This nominal species was described under the generic name Spixosoma, which is an “unjustified emendation of Sphyxosoma Rondani, 1856 ” (O’Hara et al. 2011: 170). Stuke (2017: 51) only reported the three male and three female syntypes in the MZUF and did not mention those in the other collections. We found ten syntypes in this study.
description: Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on page 97, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621
Wang-Landau molecular dynamics technique to search for low-energy conformational space of proteins
Creators: name: Nagasima, Takehiro
name: Kinjo, Akira R.
name: Mitsui, Takashi
name: Nishikawa, Ken
Publisher: name: arXiv
Year: 2007
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: Multicanonical molecular dynamics (MD) is a powerful technique for sampling conformations on rugged potential surfaces such as protein. However, it is notoriously difficult to estimate the multicanonical temperature effectively. Wang and Landau developed a convenient method for estimating the density of states based on a multicanonical Monte Carlo method. In their method, the density of states is calculated autonomously during a simulation. In this paper we develop a set of techniques to effectively apply the Wang-Landau method to MD simulations. In the multicanonical MD, the estimation of the derivative of the density of states is critical. In order to estimate it accurately, we devise two original improvements. First, the correction for the density of states is made smooth by using the Gaussian distribution obtained by a short canonical simulation. Second, an approximation is applied to the derivative, which is based on the Gaussian distribution and the multiple weighted histogram technique. A test of this method was performed with small polypeptides, Met-enkephalin and Trp-cage, and it is demonstrated that Wang-Landau MD is consistent with replica exchange MD but can sample much larger conformational space.
description: 8 pages, 7 figures, accepted for publication in Physical Review E
Leggett-Garg inequalities and decays of unstable systems
Creators: name: Giacosa, Francesco
name: Pagliara, Giuseppe
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We apply the Leggett-Garg inequalities (LGI) to the case of classical and quantum unstable systems. For classical systems the two assumptions of macroscopic realism and non-invasive measurements imply that the three-measurement string $K_3$ is identically equal to one. Also for quantum mechanical systems -- for which the two assumptions are in general not valid -- we find that $K_3=1$ for purely exponential decays ($K_3\leq1$ is the general LGI). On the other hand, the necessary deviations from the exponential decay law at short and long times predicted by quantum mechanics lead to values of $K_3 \neq 1$. Moreover, a strict violations $K_3>1$ occurs typically at short times. Thus, we conclude that experiments in which such deviations from the exponential decay law have been observed should also find in their data violations of the LGIs.
description: 8 pages, 4 figures, revised and extended version
The Relationship between the Optical Depth of the 9.7 micron Silicate Absorption Feature and Infrared Differential Extinction in Dense Clouds
Creators: name: Chiar, J. E.
name: Ennico, K.
name: Pendleton, Y. J.
name: Boogert, A. C. A.
name: Greene, T.
name: Knez, C.
name: Lada, C.
name: Roellig, T.
name: Tielens, A. G. G. M.
name: Werner, M.
name: Whittet, D. C. B.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We have examined the relationship between the optical depth of the 9.7 micron silicate absorption feature (tau_9.7) and the near-infrared color excess, E(J-Ks) in the Serpens, Taurus, IC 5146, Chameleon I, Barnard 59, and Barnard 68 dense clouds/cores. Our data set, based largely on Spitzer IRS spectra, spans E(J-Ks)=0.3 to 10 mag (corresponding to visual extinction between about 2 and 60 mag.). All lines of sight show the 9.7 micron silicate feature. Unlike in the diffuse ISM where a tight linear correlation between the 9.7 micron silicate feature optical depth and the extinction (Av) is observed, we find that the silicate feature in dense clouds does not show a monotonic increase with extinction. Thus, in dense clouds, tau_9.7 is not a good measure of total dust column density. With few exceptions, the measured tau_9.7 values fall well below the diffuse ISM correlation line for E(J-Ks) > 2 mag (Av >12 mag). Grain growth via coagulation is a likely cause of this effect.
description: 11 pages including 2 figures, 1 table. Accepted for publication in ApJ Letters, 23 July 2007
Dynamics of a strongly interacting Fermi gas: the radial quadrupole mode
Creators: name: Altmeyer, A.
name: Riedl, S.
name: Wright, M. J.
name: Kohstall, C.
name: Denschlag, J. Hecker
name: Grimm, R.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We report on measurements of an elementary surface mode in an ultracold, strongly interacting Fermi gas of 6Li atoms. The radial quadrupole mode allows us to probe hydrodynamic behavior in the BEC-BCS crossover without being influenced by changes in the equation of state. We examine frequency and damping of this mode, along with its expansion dynamics. In the unitarity limit and on the BEC side of the resonance, the observed frequencies agree with standard hydrodynamic theory. However, on the BCS side of the crossover, a striking down shift of the oscillation frequency is observed in the hydrodynamic regime as a precursor to an abrupt transition to collisionless behavior; this indicates coupling of the oscillation to fermionic pairs.
description: 11 pages, 11 figures v2: minor changes
Supplementary document for Anomalous generalized Brewster effect and ultra-broadband reflectionless Brewster metasurfaces - 5982247.pdf
Creators: name: fan, huiying
name: Chu, Hongchen
name: luo, hao
name: Lai, Yun
name: Gao, Lei
name: luo, jie
Publisher: name: Optica Publishing Group
Year: 2022
Subjects: Uncategorized

description: Supplemental Document
Anthomyia luteiventris Rondani 1873
Creators: name: Sforzi, Alessandra
name: Sommaggio, Daniele
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Anthomyiidae
Anthomyia
Anthomyia luteiventris

description: Anthomyia luteiventris Rondani, 1873
ORIGINAL DESCRIPTION: 1873e: 288.
TYPE LOCALITY: “ Keren [Keren (Eritrea)]”.
TYPE MATERIAL: 1 ♀, holotype (MSNG): Bogos 1870, Keren, O. Beccari / Typus / luteiventris Rond., ♀ / Anthomyia luteiventris, ♀.
CURRENT STATUS: valid species, as Dichaetomyia luteiventris (Pont 1980a: 739).
REMARKS: Rondani (1873e: 288) described Anthomyia luteiventris from just the female sex, without specifying the exact number of specimens, but giving a single measurement of length, from material collected by O. Beccari and O. Antinori. Guiglia (1957: 193) and Raineri & Rey (1996: 28) reported the holotype (♀) in the MSNG.
description: Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on page 139, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621
Boundary integral formulations for acoustic modelling of high-contrast media
Creators: name: Wout, Elwin van 't
name: Haqshenas, Seyyed R.
name: Gélat, Pierre
name: Betcke, Timo
name: Saffari, Nader
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: The boundary element method is an efficient algorithm for simulating acoustic propagation through homogeneous objects embedded in free space. The conditioning of the system matrix strongly depends on physical parameters such as density, wavespeed and frequency. In particular, high contrast in density and wavespeed across a material interface leads to an ill-conditioned discretisation matrix. Therefore, the convergence of Krylov methods to solve the linear system is slow. Here, specialised boundary integral formulations are designed for the case of acoustic scattering at high-contrast media. The eigenvalues of the resulting system matrix accumulate at two points in the complex plane that depend on the density ratio and stay away from zero. The spectral analysis of the Calderón preconditioned PMCHWT formulation yields a single accumulation point. Benchmark simulations demonstrate the computational efficiency of the high-contrast Neumann formulation for scattering at high-contrast media.
Azelia parva Rondani 1866
Creators: name: Sforzi, Alessandra
name: Sommaggio, Daniele
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Anthomyiidae
Azelia
Azelia parva

description: Azelia parva Rondani, 1866
ORIGINAL DESCRIPTION: 1866a: 133 (key), 134 (description).
TYPE LOCALITY: “ in collibus agri parmensis [Parmese hills (Italy)]”.
TYPE MATERIAL: 1 ♂, syntype (head glued to the thorax, right wing damaged, missing left mid-, left hind-, and right mid-legs) (MZUF: Box 25): Azelia Desv. / parva Rndn., ♂, Parma / 1351; 2 ♀♀, syntypes (MZUF: Box 25): Azelia Desv. / parva Rndn., ♀, Parma / 1352.
CURRENT STATUS: valid species (Pont 1986b: 63).
REMARKS: Rondani (1866a: 134) described both sexes of Azelia parva without specifying the exact number of specimens and not giving a range of length. The male syntype and the two female syntypes in the MZUF are numbered, respectively, “1351” and “1352”.
description: Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on page 141, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621
AMS :: ATX January 2018 Blog Archive
Creators: name: Department Of American Studies
Publisher: name: American Studies
Year: 2018
Subjects: American Studies
Twitter

description: Contents: Dr. Randolph Lewis Interviewed in National Geographic Cover Story, “They Are Watching You..” -- Dr. Betsy Beasley to Give Lecture on Houston’s Historical Development as a Service Empire
description: @AmStudies is a Twitter feed dedicated to representing the many activities and interests of the department of American Studies at The University of Texas at Austin. Together with the department’s blog, this feed exists to serve the AMS and Austin communities by acting as a hub for up-to-date information on events and opportunities at UT and beyond.
Random walks of Wilson loops in the screening regime
Creators: name: Buividovich, P. V.
name: Polikarpov, M. I.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Dynamics of Wilson loops in pure Yang-Mills theories is analyzed in terms of random walks of the holonomies of the gauge field on the gauge group manifold. It is shown that such random walks should necessarily be free. The distribution of steps of these random walks is related to the spectrum of string tensions of the theory and to certain cumulants of Yang-Mills curvature tensor. It turns out that when colour charges are completely screened, the holonomies of the gauge field can change only by the elements of the group center, which indicates that in the screening regime confinement persists due to thin center vortices. Thick center vortices are also considered and the emergence of such stepwise changes in the limits of infinitely thin vortices and infinitely large loops is demonstrated.
description: Major revision of the previous version, to appear in Nucl. Phys. B (10 pages RevTeX, 3 figures)
AMS :: ATX March 2018 Blog Archive
Creators: name: Department Of American Studies
Publisher: name: American Studies
Year: 2018
Subjects: American Studies
Twitter

description: Contents: TONIGHT: Siva Vaidhyanathan Speaks on “Antisocial Media”: BMC 2.106, 7 PM -- Rapoport Center Hosts Event, 3/29: “The Role of Law in the Production of Inequality.” Shirley E. Thompson (UT AMS), Walter Johnson Among Speakers
description: @AmStudies is a Twitter feed dedicated to representing the many activities and interests of the department of American Studies at The University of Texas at Austin. Together with the department’s blog, this feed exists to serve the AMS and Austin communities by acting as a hub for up-to-date information on events and opportunities at UT and beyond.
Parsec-scale properties of the peculiar gigahertz-peaked spectrum quasar 0858-279
Creators: name: Kosogorov, N. A.
name: Kovalev, Y. Y.
name: Perucho, M.
name: Kovalev, Yu. A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We performed multi-frequency studies on the gigahertz-peaked spectrum high-redshift quasar 0858-279. Initially, the source presented itself in the early VLBI images as a very peculiar resolved blob. We observed the quasar with the VLBA at 1.4-24 GHz in a dual-polarization mode. The high spatial resolution and the spectral index maps enabled us to resolve the core-jet structure and locate a weak and compact core by its inverted spectrum. The dominant jet component 20 parsecs away from the core was optically thin above 10 GHz and opaque below it. We also estimated an uncommonly strong magnetic field in the bright jet feature, which turned out to be around 1 G. The Faraday rotation measure maps revealed high RM values over 6000 rad/m^2. Additionally, these maps allowed us to follow the magnetic field direction in the bright jet feature being perpendicular to the propagation direction of the jet. All the results strongly indicated the formation of a shock wave in the dominant component arising from an interaction with the surrounding matter. Using the proposed hypothesis and the core shift approach, we discovered that the magnetic field in the core region is of the order of 0.1 G.
description: 15 pages, 12 figures, accepted for publication in MNRAS
Observational biases in Lagrangian reconstructions of cosmic velocity fields
Creators: name: Lavaux, G.
name: Mohayaee, R.
name: Colombi, S.
name: Tully, R. B.
name: Bernardeau, F.
name: Silk, J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Lagrangian reconstruction of large-scale peculiar velocity fields can be strongly affected by observational biases. We develop a thorough analysis of these systematic effects by relying on specially selected mock catalogues. For the purpose of this paper, we use the MAK reconstruction method, although any other Lagrangian reconstruction method should be sensitive to the same problems. We extensively study the uncertainty in the mass-to-light assignment due to luminosity incompleteness, and the poorly-determined relation between mass and luminosity. The impact of redshift distortion corrections is analyzed in the context of MAK and we check the importance of edge and finite-volume effects on the reconstructed velocities. Using three mock catalogues with different average densities, we also study the effect of cosmic variance. In particular, one of them presents the same global features as found in observational catalogues that extend to 80 Mpc/h scales. We give recipes, checked using the aforementioned mock catalogues, to handle these particular observational effects, after having introduced them into the mock catalogues so as to quantitatively mimic the most densely sampled currently available galaxy catalogue of the nearby universe. Once biases have been taken care of, the typical resulting error in reconstructed velocities is typically about a quarter of the overall velocity dispersion, and without significant bias. We finally model our reconstruction errors to propose an improved Bayesian approach to measure Omega_m in an unbiased way by comparing the reconstructed velocities to the measured ones in distance space, even though they may be plagued by large errors. We show that, in the context of observational data, a nearly unbiased estimator of Omega_m may be built using MAK reconstruction.
description: 29 pages, 21 figures, 6 tables, Accepted by MNRAS on 2007 October 2. Received 2007 September 30; in original form 2007 July 24
Extragalactic magnetic field constraints from ultra-high-energy cosmic rays from local galaxies
Creators: name: van Vliet, Arjen
name: Palladino, Andrea
name: Taylor, Andrew
name: Winter, Walter
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We interpret the correlation between local star-forming galaxy positions and ultra-high-energy cosmic ray (UHECR) directions, recently detected by the Pierre Auger Observatory (PAO), in terms of physical parameters: the local density of sources and the magnetic fields governing the UHECR propagation. We include a Galactic magnetic field model on top of a random extragalactic magnetic field description to determine the level of UHECR deflections expected from an ensemble of source positions. Besides deflections in magnetic fields, we also take into account energy losses with background photon fields as well as spectrum and composition measurements by the PAO. We find consistency between the PAO anisotropy measurement and the local star-forming galaxy density for large extragalactic magnetic field strengths with $B > 0.2 \ \rm nG$ (for a coherence length of $1 \ \rm Mpc$) at the $5σ$ confidence level. Larger source densities lead to more isotropic background and consequently allow for weaker extragalactic magnetic fields. However, the acceleration of UHECR by such abundant sources is more challenging to motivate. Too large source densities and extragalactic magnetic field strengths, on the other hand, are also disfavored as that decreases the expected level of anisotropy. This leads to upper limits of $B < 22 \ \rm nG$ and $ρ_0 < 8.4 \cdot 10^{-2} \ \rm Mpc^{-3}$ at the 90\% confidence level.
description: 10 pages, 6 figures, incl. appendices, accepted for publication in MNRAS