cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Shadows and thin accretion disk images of the $γ$-metric
Creators: name: Shaikh, Rajibul
name: Paul, Suvankar
name: Banerjee, Pritam
name: Sarkar, Tapobrata
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The $γ$-metric is a static, axially-symmetric singular solution of the vacuum Einstein's equations without an event horizon. This is a two-parameter family of solutions, generic values of one of which (called $γ$) measure the deviation from spherical symmetry. Here, we first study the shadow cast by this geometry, in order to constrain the $γ$-metric from observations. We find that for $γ< 1/2$, there are, in principle, no shadows cast. On the other hand, shadows cast for all values of $γ\geq 1/2$ are consistent with observations of M$87^*$ by the Event Horizon Telescope. We also study images of thin accretion disks in the $γ$-metric background. In situations where the $γ$-metric possesses light rings, these qualitatively mimic Schwarzschild black holes with the same ADM mass, while in the absence of such rings, they are drastically different from the black hole case.
description: 14 pages, 22 figures
Discovery of molecular hydrogen in SN 1987A
Creators: name: Fransson, Claes
name: Larsson, Josefin
name: Spyromilio, Jason
name: Leibundgut, Bruno
name: McCray, Richard
name: Jerkstrand, Anders
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Both CO and SiO have been observed at early and late phases in SN 1987A. H_2 was predicted to form at roughly the same time as these molecules, but was not detected at early epochs. Here we report the detection of NIR lines from H_2 at 2.12 mu and 2.40 mu in VLT/SINFONI spectra obtained between days 6489 and 10,120. The emission is concentrated to the core of the supernova in contrast to H-alpha and approximately coincides with the [Si I]/[Fe II] emission detected previously in the ejecta. Different excitation mechanisms and power sources of the emission are discussed. From the nearly constant H_2 luminosities we favour excitation resulting from the 44Ti decay.
description: 5 pages 3 figures, accepted for ApJ Letters
Detailed homogeneous abundance studies of 14 Galactic s-process enriched post-AGB stars: In search of lead (Pb)
Creators: name: De Smedt, Kenneth
name: Van Winckel, Hans
name: Kamath, Devika
name: Siess, Lionel
name: Goriely, Stephane
name: Karakas, Amanda I.
name: Manick, Rajeev
Publisher: name: arXiv
Year: 2015
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: This paper is part of a larger project in which we systematically study the chemical abundances of Galactic and extragalactic post-asymptotic giant branch (post-AGB) stars. Lead (Pb) is the final product of the s-process nucleosynthesis and is predicted to have large overabundances with respect to other s-process elements in AGB stars of low metallicities. However, Pb abundance studies of enriched post-AGB stars in the Magellanic Clouds show the Pb overabundance is not observed. We used high-resolution UVES and HERMES spectra for detailed spectral abundance studies of our sample of 14 Galactic post-AGB stars. We do not find any clear evidence of Pb overabundances in our sample. Stars with T(eff) > 7500 K do not provide strong constraints on the Pb abundance. We conclude that the discrepancy between theory and observation increases towards lower metallicities. All objects, except IRAS 17279-1119, confirm the relation between neutron exposure [hs/ls] and third dredge-up efficiency [s/Fe], whereas no relation between metallicity and neutron exposure is detected within the metallicity range of our total sample (-1.4 < [Fe/H] < -0.2). The mild enrichment of IRAS 17279-1119 can probably be attributed to a cut-off of the AGB evolution due to binary interactions. To our knowledge, IRAS 17279-1119 is the first s-process enhanced Galactic post-AGB star known in a binary system and is a possible precursor of the extrinsic Ba dwarf stars. Lead-rich stars have yet to be found in post-AGB stars. extrinsic Ba dwarf stars. Lead-rich stars are yet to be found in post-AGB stars.
description: 26 pages, 40 figures, Accepted for publication in Astronomy and Astrophysics, main journal
Amy Jacques Garvey “On A Trip from Coast to Coast”:
Creators: name: Wiegmann, Patricia
Publisher: name: Leipziger Universitätsverlag
Year: 2011

description: Ortswechsel schwarzer Menschen waren konstituierend für die Herausbildung transatlantischer Netzwerke, die Paul Gilroy als Black Atlantic begreift. Dabei durchquerten jene den atlantischen Raum nicht nur als Versklavte und Vertriebene, sondern auch als selbstbestimmte und selbstbewusste Reisende. Der vorliegende Artikel beschäftigt sich mit der in Jamaika geborenen Reisenden Amy Jacques Garvey, die 1923 gemeinsam mit ihrem Ehemann Marcus Garvey im Dienste der Universal Negro Improvement Association (UNIA) die USA bereiste. Ihre Erlebnisse und Eindrücke hielt Amy Garvey in sechs Reisereportagen fest, die wöchentlich in der Organisationszeitschrift Negro World veröffentlicht wurden. Entlang dieser Reiseberichte untersucht der vorliegende Artikel zum einen, in welcher Weise die Reise der Garveys und insbesondere die Aktivitäten Amy Garveys als Reisereporterin zu einer transatlantischen Vernetzung beitrugen. Zum anderen diskutiert der Artikel die sowohl emanzipatorischen als auch restriktive Dimensionen, die sich für Amy Garvey an die Reise und die Berichterstattung knüpften: In welcher Weise bestimmten zeitgenössische Vorstellungen von race, class und gender die Reise Amy Garveys und ihre Möglichkeiten der Berichterstattung? Die Berichte zeichnen die Verfasserin als aktiv Handelnde aus, die in ihren Reportagen selbstbewusst Formen von Rassismus kritisiert und sich diesen im Zuge ihres Schreibens widersetzt.
description: Comparativ, Vol 21 No 5 (2011): Being on the Move: Formations of the Black Atlantic
Element Decoupling of 7T Dipole Body Arrays by EBG Metasurface Structures: Experimental Verification
Creators: name: Hurshkainen, Anna A.
name: Derzhavskaya, Tatyana A.
name: Glybovski, Stanislav B.
name: Voogt, Ingmar J.
name: Melchakova, Irina V.
name: Berg, Cornelis A. T. van den
name: Raaijmakers, Alexander J. E.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Medical Physics (physics.med-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Metasurfaces are artificial electromagnetic boundaries or interfaces usually implemented as two-dimensional periodic structures with subwavelength periodicity and engineered properties of constituent unit cells. The electromagnetic bandgap (EBG) effect in metasurfaces prevents all surface modes from propagating in a certain frequency band. While metasurfaces provide a number of important applications in microwave antennas and antenna arrays, their features are also highly suitable for MRI applications. In this work we manufacture and experimentally study finite samples based on mushroom-type EBG metasurfaces and employ them for suppression of inter-element coupling in dipole transmit coil arrays for body imaging at 7T. We show experimentally that employment of the samples EBG leads to reduction of coupling between adjacent closely-spaced dipole antenna elements of a 7T transmit/receive body array, which reduces scattering losses in neighboring channels and thereby improves the B1+ efficiency. The setup consists of two fractionated dipole antennas previously designed by the authors for body imaging at 7 Tesla. These are placed on top of a body-mimicking phantom and equipped with the manufactured finite-size sample of the metasurface tuned to have EBG properties at the Larmor frequency of 298 MHz. To improve the detection range of the B1+ field distribution of the top elements, four additional elements were positioned along the bottom side of the phantom. Scattering matrix measurements show that coupling between the two top elements is indeed reduced while the measurements performed on a 7T MRI machine confirm the array's B1+ efficiency improvement due to reduced scattering losses. This study provides a tool for the decoupling of dipole antennas in ultrahigh field transmit arrays, possibly resulting in denser element placement and/or larger subject-element spacing.
Monolayer MoSe2: A candidate for room temperature polaritonics
Creators: name: Lundt, N.
name: Maryński, A.
name: Cherotchenko, E.
name: Pant, A.
name: Fan, X.
name: Sęk, G.
name: Tongay, S.
name: Kavokin, A. V.
name: Höfling, S.
name: Schneider, C.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Monolayered MoSe2 is a promising new material to investigate advanced light-matter coupling as it hosts stable and robust excitons with comparably narrow optical resonances. In this work, we investigate the evolution of the lowest lying excitonic transition, the so-called A-valley exciton, with temperature. We find a strong, phonon-induced temperature broadening of the resonance, and more importantly, a reduction of the oscillator strength for increased temperatures. Based on these experimentally extracted, temperature dependent parameters, we apply a coupled oscillator model to elucidate the possibility to observe the strong coupling regime between the A-exciton and a microcavity resonance in three prototypical photonic architectures with varying mode volumes. We find that the formation of exciton-polaritons up to ambient conditions in short, monolithic dielectric and Tamm-based structures seems feasible. In contrast, a temperature-induced transition into the weak coupling regime can be expected for structures with extended effective cavity length. Based on these findings, we calculate and draw the phase diagram of polariton Bosonic condensation in a MoSe2 cavity.
Particles within extended-spin space: Lagrangian connection
Creators: name: Besprosvany, J.
name: Romero, R.
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: A spin-space extension is reviewed, which provides information on the standard model. Its defining feature is a common matrix space that describes symmetries and representations, and leads to limits on these, for given dimension. The model provides additional information on the standard model, whose interpretation requires an interactive formulation. Within this program, we compare the model's lepton-W generated interactive Lagrangian in (5+1)-dimensions, and that of the standard model. We derive the conditions for this matching, which apply to other Lagrangian terms. We also discuss the advantages of this extension, as compared to others.
description: Talk presented at the 10th Latin American Symposium on High Energy Physics (SILAFAE 2014) 24-28 Nov 2014. Medellin, Colombia. 15 pages, 1 figure, 1 table, 15 references
Breakdown of hydrodynamics below four dimensions in a fracton fluid
Creators: name: Glorioso, Paolo
name: Guo, Jinkang
name: Rodriguez-Nieva, Joaquin F.
name: Lucas, Andrew
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We present the nonlinear fluctuating hydrodynamics which governs the late time dynamics of a chaotic many-body system with simultaneous charge/mass, dipole/center of mass, and momentum conservation. This hydrodynamic effective theory is unstable below four spatial dimensions: dipole-conserving fluids at rest become unstable to fluctuations, and are governed not by hydrodynamics, but by a fractonic generalization of the Kardar-Parisi-Zhang universality class. We numerically simulate many-body classical dynamics in one-dimensional models with dipole and momentum conservation, and find evidence for a breakdown of hydrodynamics, along with a new universality class of undriven yet non-equilbrium dynamics.
description: 6+5 pages, 4 figures
Cuban Teachers in Angola:
Creators: name: Hatzky, Christine
Publisher: name: Leipziger Universitätsverlag
Year: 2011

description: Der kubanische Staatschef Fidel Castro definierte Kuba 1975 als eine „lateinamerikanisch-afrikanische Nation“. Diese Ankündigung war überraschend, denn seit dem Verbot des Rassismus nach der Revolution waren Diskussionen über die afrikanische Herkunft eines großen Teils der kubanischen Bevölkerung Tabu. Castro benötigte jedoch einerseits Tausende von Freiwilligen für die militärische und zivile Kooperation mit dem unabhängigen Angola, andererseits musste er den größten transatlantischen Auslandseinsatz in der Geschichte Kubas politisch rechtfertigen. Diese damit implizierte Annahme einer gemeinsam-geteilten Identität von Kubanern und Angolanern ist der Ausgangspunkt für neue Überlegungen zur Bedeutung des Konzepts des „Black Atlantic“. Sie basieren auf meinem kürzlich beendeten Postdoc-Forschungsprojekt über die kubanisch-angolanischen Kooperation im Bildungsbereich: Kubaner in Angola. Süd-SüdKooperation und Bildungstransfer 1976–1991.
description: Comparativ, Vol 21 No 5 (2011): Being on the Move: Formations of the Black Atlantic
More than open data: towards a FAIR data and simulation infrastructure with AiiDA and Materials Cloud
Creators: name: Pizzi, Giovanni
Publisher: name: Zenodo
Year: 2023

description: High-throughput computational materials discovery studies can generate sheer amounts of interconnected data. Making such data open and FAIR is only possible with proper workflow tools that not only automate the simulations, but also deal appropriately with data management. I will discuss how we address these challenges with the open-source high-throughput infrastructure AiiDA [1], an automated and scalable solution for workflow management, data provenance storage and reproducibility, supported by a broad community of developers (over 120 different simulation engines are supported by AiiDA, see the AiiDA plugin registry [2]). After introducing AiiDA, I will discuss how we can achieve FAIR data sharing when combining AiiDA with our Materials Cloud platform [3]. I will then focus on how we can go beyond "just" open FAIR data, toward making also simulations FAIR. We target accessibility of advanced HPC workflows with the development of AiiDA common workflow (ACWF) interfaces, to perform routine material-science tasks with a single input/output interface [4]. We demonstrate how any user can perform in a reproducible way, e.g., structural relaxations via a single common interface with 11 different codes (Abinit, BigDFT, CASTEP, CP2K, FLEUR, Gaussian, NWChem, ORCA, Quantum ESPRESSO, Siesta VASP). These workflows only require the user to provide an input crystal or molecular structure, and all other numerical inputs are automatically selected appropriately for each code. Accessibility is then further increased combining AiiDA's workflows with the AiiDAlab graphical interface [5]. The value of the ACWF approach is demonstrated by our recent collaborative effort [6] to test precision and transferability of DFT methods across chemistries (all elements from hydrogen to curium, in 10 prototypical crystal structures), resulting in a reference dataset of 960 equations of state cross-checked between two all-electron codes, then used to verify and improve 9 other pseudopotential methods. I will conclude discussing efforts to generalise the use of our simulation infrastructure beyond its initial domain, towards e.g. atmospheric physics, weather and climate applications, and even driving robotic experiments. [1] https://www.aiida.net - S.P. Huber et al., Scientific Data 7, 300 (2020). [2] https://aiidateam.github.io/aiida-registry/ [3] https://www.materialscloud.org/ - L. Talirz et al., Sci Data 7, 299 (2020). [4] https://github.com/aiidateam/aiida-common-workflows - S. P. Huber et al., npj Comput Mater 7, 136 (2021).
description: {"references": ["https://www.aiida.net", "https://aiidateam.github.io/aiida-registry/", "https://www.materialscloud.org/", "https://github.com/aiidateam/aiida-common-workflows"]}
Are IRIS bombs connected to Ellerman bombs?
Creators: name: Tian, Hui
name: Xu, Zhi
name: He, Jiansen
name: Madsen, Chad
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Recent observations by the Interface Region Imaging Spectrograph (IRIS) have revealed pockets of hot gas ($\sim$2--8$\times$10$^{4}$ K) potentially resulting from magnetic reconnection in the partially ionized lower solar atmosphere (IRIS bombs; IBs). Using joint observations between IRIS and the Chinese New Vacuum Solar Telescope, we have identified ten IBs. We find that three are unambiguously and three others are possibly connected to Ellerman bombs (EBs), which show intense brightening of the extended H$_α$ wings without leaving an obvious signature in the H$_α$ core. These bombs generally reveal the following distinct properties: (1) The O~{\sc{iv}}~1401.156Å and 1399.774Å lines are absent or very weak; (2) The Mn~{\sc{i}}~2795.640Å line manifests as an absorption feature superimposed on the greatly enhanced Mg~{\sc{ii}}~k line wing; (3) The Mg~{\sc{ii}}~k and h lines show intense brightening in the wings and no dramatic enhancement in the cores; (4) Chromospheric absorption lines such as Ni~{\sc{ii}}~1393.330Å and 1335.203Å are very strong; (5) The 1700Å images obtained with the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory reveal intense and compact brightenings. These properties support the formation of these bombs in the photosphere, demonstrating that EBs can be heated much more efficiently than previously thought. We also demonstrate that the Mg~{\sc{ii}}~k and h lines can be used to investigate EBs similarly to H$_α$, which opens a promising new window for EB studies. The remaining four IBs obviously have no connection to EBs and they do not have the properties mentioned above, suggesting a higher formation layer possibly in the chromosphere.
description: 10 figures, accepted by ApJ
Polarization doping ab initio verification of the concept charge conservation and nonlocality
Creators: name: Ahmad, Ashfaq
name: Strak, Pawel
name: Kempisty, Pawel
name: Sakowski, Konrad
name: Piechota, Jacek
name: Kangawa, Yoshihiro
name: Grzegory, Izabella
name: Leszczynski, Michal
name: Zytkiewicz, Zbigniew R.
name: Muziol, Grzegorz
name: Monroy, Eva
name: Krukowski, Stanislaw
name: Kaminska, Agata
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: In this work, we study the emergence of polarization doping in AlxGa1-xN layers with graded composition from a theoretical viewpoint. We demonstrate that the charge conservation law applies for fixed and mobile charges separately, leading to nonlocal compensation phenomena involving bulk fixed and mobile charge and polarization sheet charge at the heterointerfaces. The magnitude of the effect allows obtaining technically viable mobile charge density for optoelectronic devices without impurity doping (donors or acceptors). Therefore, it provides an additional tool for the device designer, with the potential to attain high conductivities: high carrier concentrations can be obtained even in materials with high dopant ionization energies, and the mobility is not limited by scattering at ionized impurities.
description: 16 pages, 4 figures
Beyond the Black Atlantic:
Creators: name: Stubbs, Jean
Publisher: name: Leipziger Universitätsverlag
Year: 2011

description: Aus historischer Perspektive lässt sich die Karibik nicht nur als Teil einer Atlantischen, sondern darüber hinaus einer globalen Welt verstehen. Im Zuge der kolonialen Expansion zirkulierten zwischen den als East und West Indies bezeichneten Regionen, Güter, Menschen und Ideen. Im 19. Jahrhundert war Kuba ein Knotenpunkt innerhalb der so entstandenen Netzwerke, und die kubanische Zigarre etablierte sich als globales Luxusprodukt. In vielen Teilen der Welt begehrt und nachgeahmt, wurde El Habano zu einem mythenumgebenen Herzstück transnationaler Produktions- und Handlungsprozesse: industrielles und agrikulturelles Wissen, Saatgut sowie menschliche Arbeitskräfte wanderten zwischen den verschiedenen Regionen umher. Der Artikel verfolgt die grenzüberschreitenden Wege und Mythen von El Habano vom 19. bis ins 21. Jahrhundert und nimmt verschiedenen Stätten der Produktion in Kuba, Florida, Connecticut sowie Indonesien in den Blick.
description: Comparativ, Vol 21 No 5 (2011): Being on the Move: Formations of the Black Atlantic
1d Quantum Harmonic Oscillator Perturbed by a Potential with Logarithmic Decay
Creators: name: Wang, Zhiguo
name: Liang, Zhenguo
Publisher: name: arXiv
Year: 2016
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics

description: In this paper we prove an infinite dimensional KAM theorem, in which the assumptions on the derivatives of perturbation in \cite{GT} are weakened from polynomial decay to logarithmic decay. As a consequence, we apply it to 1d quantum harmonic oscillators and prove the reducibility of a linear harmonic oscillator, $T=- \frac{d^2}{dx^2}+x^2$, on $L^2(\R)$ perturbed by a quasi-periodic in time potential $V(x,ωt; ω)$ with logarithmic decay. This entails the pure-point nature of the spectrum of the Floquet operator $K$, where K:=-{\rm i}\sum_{k=1}^nω_k\frac{\partial}{\partial θ_k}- \frac{d^2}{dx^2}+x^2+\varepsilon V(x,θ;ω), is defined on $L^2(\R) \otimes L^2(\T^n)$ and the potential $V(x,θ;ω)$ has logarithmic decay as well as its gradient in $ω$.
description: arXiv admin note: substantial text overlap with arXiv:1003.2793 by other authors
Chocolate, Race, and the Atlantic World:
Creators: name: Hackenesch, Silke
Publisher: name: Leipziger Universitätsverlag
Year: 2011

description: Vor dem Hintergrund des Black Atlantic argumentiert der vorliegende Artikel, dass Kakao/Schokolade und Blackness vielschichtig – auf diskursiven und materiellen Ebenen – miteinander verknüpft sind. Es waren seit dem frühen 20. Jahrhundert in erster Linie versklavte schwarze Subjekte, die die Kakaobohnen auf Plantagen in Westafrika ernteten, und diese Produktionsbedingungen fanden nicht nur Eingang in das semantische Feld rund um Schokolade, in dem diese als exotisches Genussmittel, als Aphrodisiakum, oder als Luxusgut konstruiert worden ist, sondern auch in die visuelle Bildsprache von Schokoladenreklame, die häufig koloniale Phantasiewelten evozierte, in denen „exotische“ Menschen an „tropischen“ Orten Kakao ernteten. Schokolade fungiert hier, in Anlehnung an Roland Barthes, als Mythos, denn es erscheint in den Quellen selbsterklärend und vermeintlich „natürlich“, warum ein ehemals koloniales Produkt mit (Imaginationen von) Blackness verwoben wird. Interessanterweise taucht chocolate in afrikanisch-amerikanischen kulturellen Kontexten aber auch als affirmative und positiv konnotierte Selbstbezeichnung auf, und – im Gegensatz zu Deutschland – als emanzipatorische und häufig sexuell aufgeladene Aufforderung einer positiven Identifikation mit Blackness.
description: Comparativ, Vol 21 No 5 (2011): Being on the Move: Formations of the Black Atlantic
Lowering one's net deeper and deeper : the cutural and ethical components of palliative care
Creators: name: Philip., Jennifer A.M.
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Phase field modeling of partially saturated deformable porous media
Creators: name: Sciarra, Giulio
Publisher: name: arXiv
Year: 2016
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A poromechanical model of partially saturated deformable porous media is proposed based on a phase field approach at modeling the behavior of the mixture of liquid water and wet air, which saturates the pore space, the phase field being the saturation (ratio). While the standard retention curve is expected still to provide the intrinsic retention properties of the porous skeleton, depending on the porous texture, an enhanced description of surface tension between the wetting (liquid water) and the non-wetting (wet air) fluid, occupying the pore space, is stated considering a regularization of the phase field model based on an additional contribution to the overall free energy depending on the saturation gradient. The aim is to provide a more refined description of surface tension interactions. An enhanced constitutive relation for the capillary pressure is established together with a suitable generalization of Darcy's law, in which the gradient of the capillary pressure is replaced by the gradient of the so-called generalized chemical potential, which also accounts for the \lq\lq force\rq\rq\, associated to the local free energy of the phase field model. A micro-scale heuristic interpretation of the novel constitutive law of capillary pressure is proposed, in order to compare the envisaged model with that one endowed with the concept of average interfacial area. The considered poromechanical model is formulated within the framework of strain gradient theory in order to account for possible effects, at laboratory scale, of the micro-scale hydro-mechanical couplings between highly-localized flows (fingering) and localized deformations of the skeleton (fracturing).
title: A Compact Dual-Polarized Filtering Antenna with Steep Cut-Off for Base-Station Applications (accepted)
Creators: name: Liu, Xuekang
name: Gao, Steven
name: Hu, Wei
name: Wen, Lehu
name: Luo, Qi
name: Sanz-Izquierdo, Benito
name: Chen, Ziaodong
name: Quan, Long
name: Tetuko Sri Sumantyo, Josaphat
name: Yang, Xue-Xia
Publisher: name: IEEE
Year: 2022

description: A dual-polarized filtering antenna with steep cut-off and compact size is developed for base station applications. In this design, four controllable radiation nulls are obtained by utilizing split rings, slotted T-shaped branches, a single-stub tuner, and a parasitic loop. Split rings are firstly used as the dipole arms to obtain the 1st radiation null at upper out-of-band. Four T-shaped branches working as DGS are printed under the crossed dipoles to achieve the 2nd radiation null. The connected outer conductors of the differential feed structure acting as a single-stub tuner can provide the 3rd radiation null to further enhance the upper-band rejection. Finally, a parasitic loop is incorporated around the split rings, and the out-of-band rejection of the lower-band is further enhanced by the 4th radiation null. More importantly, the impedance bandwidth of the antenna can be expended with two newly introduced resonant modes. As a result, a compact filtering antenna with a wide operational bandwidth of 1.7- 3.01 GHz (56%) is realized for |Sdd11| < -15 dB with the isolation higher than 38 dB. The out-of-band suppression is higher than 18.4 dB in 3.1-4.5 GHz and more than 47 dB in 0.8-1.1 GHz.
description: Author's Accepted Manuscript
Tidal excitation of the obliquity of Earth-like planets in the habitable zone of M-dwarf stars
Creators: name: Valente, Ema F. S.
name: Correia, Alexandre C. M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Close-in planets undergo strong tidal interactions with the parent star that modify their spins and orbits. In the two-body problem, the final stage for tidal evolution is the synchronisation of the rotation and orbital periods, and the alignment of the planet spin axis with the normal to the orbit (zero planet obliquity). The orbital eccentricity is also damped to zero, but over a much longer timescale, that may exceed the lifetime of the system. For non-zero eccentricities, the rotation rate can be trapped in spin-orbit resonances that delay the evolution towards the synchronous state. Here we show that capture in some spin-orbit resonances may also excite the obliquity to high values rather than damp it to zero. Depending on the system parameters, obliquities of 60 to 80 degrees can be maintained throughout the entire lifetime of the planet. This unexpected behaviour is particularly important for Earth-like planets in the habitable zone of M-dwarf stars, as it may help to sustain temperate environments and thus more favourable conditions for life.
description: 12 pages, 9 figures, 2 tables
Beyond the Slave Ship:
Creators: name: Niaah, Sonjah Stanley
Publisher: name: Leipziger Universitätsverlag
Year: 2011

description: Black Music und ihre Performanzen sind Praktiken, der weitreichende kulturelle und historische Kontinuitäten vorgewiesen werden können. Der Artikel untersucht drei Ausdrucksformen und ihre nationenübergreifenden Interdependenzen. Dabei werden verschiedene geographische und performative Räume mit einander verknüpft. Vom Middle Passage Slave Ship Limbo führt der Artikel zum US-amerikanischen Blues und Jamaikanischen Dancehall bis hin zu den Südafrikanischen Shebens und zeigt auf, wie sich diese kulturellen Praktiken und Räume in Ausformungen gegenseitig bedingen und verändern.
description: Comparativ, Vol 21 No 5 (2011): Being on the Move: Formations of the Black Atlantic
Connecting geometry and performance of two-qubit parameterized quantum circuits
Creators: name: Katabarwa, Amara
name: Sim, Sukin
name: Koh, Dax Enshan
name: Dallaire-Demers, Pierre-Luc
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Parameterized quantum circuits (PQCs) are a central component of many variational quantum algorithms, yet there is a lack of understanding of how their parameterization impacts algorithm performance. We initiate this discussion by using principal bundles to geometrically characterize two-qubit PQCs. On the base manifold, we use the Mannoury-Fubini-Study metric to find a simple equation relating the Ricci scalar (geometry) and concurrence (entanglement). By calculating the Ricci scalar during a variational quantum eigensolver (VQE) optimization process, this offers us a new perspective to how and why Quantum Natural Gradient outperforms the standard gradient descent. We argue that the key to the Quantum Natural Gradient's superior performance is its ability to find regions of high negative curvature early in the optimization process. These regions of high negative curvature appear to be important in accelerating the optimization process.
Dataset structure and description
Creators: name: Bhowmik, Arghya
name: Nandi, Surajit
name: Vegge, Tejs
Publisher: name: Technical University of Denmark
Year: 2023
Subjects: classificationCode: 340701
subject: Computational chemistry
classificationCode: 340704
subject: Theoretical quantum chemistry

description: This text file explain how data is formatted and split into files.This item is part of the collection MultiXC-QM9 with DOI: 10.11583/DTU.c.6185986
Measurements of correlations of anisotropic flow harmonics in Pb--Pb Collisions with ALICE
Creators: name: Zhou, You
Publisher: name: arXiv
Year: 2015
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We report the first measurements of the correlation strength between various anisotropic flow harmonics, using ALICE data. This correlation strength is characterized with multi-particle cumulants of mixed harmonics, which by construction depend only on the fluctuations of magnitudes of the anisotropic flow vectors. A detailed comparison to theoretical model calculations, including HIJING, Monte Carlo Glauber and hydrodynamics is also presented. These studies further constrain initial conditions, the properties and the evolution of the system to be used in theoretical simulations of heavy-ion collisions.
description: 4 pages, 4 figures, Proceedings of XXV International Conference on Ultrarelativistic Nucleus-Nucleus Collisions (Quark Matter 2015), Kobe, Japan
Time-Reversal-Based Quantum Metrology with Many-Body Entangled States
Creators: name: Colombo, Simone
name: Pedrozo-Peñafiel, Edwin
name: Adiyatullin, Albert F.
name: Li, Zeyang
name: Mendez, Enrique
name: Shu, Chi
name: Vuletic, Vladan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: In quantum metrology, entanglement represents a valuable resource that can be used to overcome the Standard Quantum Limit (SQL) that bounds the precision of sensors that operate with independent particles. Measurements beyond the SQL are typically enabled by relatively simple entangled states (squeezed states with Gaussian probability distributions), where quantum noise is redistributed between different quadratures. However, due to both fundamental limitations and the finite measurement resolution achieved in practice, sensors based on squeezed states typically operate far from the true fundamental limit of quantum metrology, the Heisenberg Limit. Here, by implementing an effective time-reversal protocol through a controlled sign change in an optically engineered many-body Hamiltonian, we demonstrate atomic-sensor performance with non-Gaussian states beyond the limitations of spin squeezing, and without the requirement of extreme measurement resolution. Using a system of 350 neutral $^{171}$Yb atoms, this signal amplification through time-reversed interaction (SATIN) protocol achieves the largest sensitivity improvement beyond the SQL ($11.8 \pm 0.5$~dB) demonstrated in any interferometer to date. Furthermore, we demonstrate a precision improving in proportion to the particle number (Heisenberg scaling), at fixed distance of 12.6~dB from the Heisenberg Limit. These results pave the way for quantum metrology using complex entangled states, with potential broad impact in science and technology. Potential applications include searches for dark matter and for physics beyond the standard model, tests of the fundamental laws of physics, timekeeping, and geodesy.
Cholesteric shells: two-dimensional blue fog and finite quasicrystals
Creators: name: Carenza, Livio Nicola
name: Gonnella, Giuseppe
name: Marenduzzo, Davide
name: Negro, Giuseppe
name: Orlandini, Enzo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We study the phase behaviour of a quasi-two dimensional cholesteric liquid crystal shell. We characterise the topological phases arising close to the isotropic-cholesteric transition, and show that they differ in a fundamental way from those observed on a flat geometry. For spherical shells, we discover two types of quasi-two dimensional topological phases: finite quasicrystals and amorphous structures, both made up by mixtures of polygonal tessellations of half-skyrmions. These structures generically emerge instead of regular double twist lattices because of geometric frustration, which disallows a regular hexagonal tiling of curved space. For toroidal shells, the variations in the local curvature of the surface stabilises heterogeneous phases where cholesteric patterns coexist with hexagonal lattices of half-skyrmions. Quasicrystals, amorphous and heterogeneous structures could be sought experimentally by self assembling cholesteric shells on the surface of emulsion droplets.
The soft drop momentum sharing fraction $z_g$ beyond leading-logarithmic accuracy
Creators: name: Cal, Pedro
name: Lee, Kyle
name: Ringer, Felix
name: Waalewijn, Wouter J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Grooming techniques, such as soft drop, play a central role in reducing sensitivity of jets to e.g. underlying event and hadronization at current collider experiments. The momentum sharing fraction $z_g$, of the two branches in a jet that pass the soft drop condition, is one of the most important observables characterizing a collinear splitting inside the jet, and directly probes the QCD splitting functions. In this work, we present a factorization framework that enables a systematic calculation of the corresponding cross section beyond leading-logarithmic (LL) accuracy, showing that this measurement is not only sensitive to the QCD charge but also the spin of the parton that initiates the jet. Our results at next-to-leading logarithmic (NLL$'$) accuracy include non-global logarithms, and provide a first meaningful assessment of the perturbative uncertainty. We present a comparison to the available experimental data from ALICE, ATLAS, and STAR and find excellent agreement.
description: 7 pages, 7 figures
A significant hardening and rising shape detected in the MeV/GeV nuFnu spectrum from the recently-discovered very-high-energy blazar S4 0954+65 during the bright optical flare in 2015 February
Creators: name: Tanaka, Y. T.
name: Gonzalez, J. Becerra
name: Itoh, R.
name: Finke, J. D.
name: Inoue, Y.
name: Ojha, R.
name: Carpenter, B.
name: Lindfors, E.
name: Krauss, F.
name: Desiante, R.
name: Shiki, K.
name: Fukazawa, Y.
name: Longo, F.
name: McEnery, J.
name: Buson, S.
name: Nilsson, K.
name: Ramazani, V. Fallah
name: Reinthal, R.
name: Takalo, L.
name: Pursimo, T.
name: Boschin, W.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We report on Fermi Large Area Telescope (LAT) and multi-wavelength results on the recently-discovered very-high-energy (VHE, $E>$ 100 GeV) blazar S4 0954+65 ($z=0.368$) during an exceptionally bright optical flare in 2015 February. During the time period (2015 February, 13/14, or MJD 57067) when the MAGIC telescope detected VHE $γ$-ray emission from the source, the Fermi-LAT data indicated a significant spectral hardening at GeV energies, with a power-law photon index of $1.8 \pm 0.1$---compared with the 3FGL value (averaged over four years of observation) of $2.34 \pm 0.04$. In contrast, Swift/XRT data showed a softening of the X-ray spectrum, with a photon index of $1.72 \pm 0.08$ (compared with $1.38 \pm 0.03$ averaged during the flare from MJD 57066 to 57077), possibly indicating a modest contribution of synchrotron photons by the highest-energy electrons superposed on the inverse Compton component. Fitting of the quasi-simultaneous ($<1$ day) broadband spectrum with a one-zone synchrotron plus inverse-Compton model revealed that GeV/TeV emission could be produced by inverse-Compton scattering of external photons from the dust torus. We emphasize that a flaring blazar showing high flux of $\gtrsim 1.0 \times 10^{-6}$ photons cm$^{-2}$ s$^{-1}$ ($E>$ 100 MeV) and a hard spectral index of $Γ_{\rm GeV} < 2.0$ detected by Fermi-LAT on daily time scales is a promising target for TeV follow-up by ground-based Cherenkov telescopes to discover high-redshift blazars, investigate their temporal variability and spectral features in the VHE band, and also constrain the intensity of the extragalactic background light.
description: 15 pages, 3 figures, 2 tables. Accepted by PASJ
Transport in polymer membranes beyond linear response: Controlling permselectivity by the driving force
Creators: name: Kim, Won Kyu
name: Milster, Sebastian
name: Roa, Rafael
name: Kanduč, Matej
name: Dzubiella, Joachim
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: In the popular solution-diffusion picture, the membrane permeability is defined as the product of the partition ratio and the diffusivity of penetrating solutes inside the membrane in the linear response regime, i.e., in equilibrium. However, of practical importance is the penetrants' flux across the membrane driven by external forces. Here, we study nonequilibrium membrane permeation orchestrated by a uniform external driving field using molecular computer simulations and continuum (Smoluchowski) theory in the stationary state. In the simulations, we explicitly resolve the penetrants' transport across a finite monomer-resolved polymer network, addressing one-component penetrant systems and mixtures. We introduce and discuss possible definitions of nonequilibrium, force-dependent permeability, representing `system' and `membrane' permeability. In particular, we present for the first time a definition of the differential permeability response to the force. We demonstrate that the latter turns out to be significantly nonlinear for low-permeable systems, leading to a high amount of selectiveness in permeability, called `permselectivity', and is tunable by the driving force. Our continuum-level analytical solutions exhibit remarkable qualitative agreement with the penetrant- and polymer-resolved simulations, thereby allowing us to characterize the underlying mechanism of permeabilities and steady-state transport beyond the linear response level.
Frauen auf dem Weg in die akademische Karriere:
Creators: name: Maurer, Trude
Publisher: name: Leipziger Universitätsverlag
Year: 2011

description: Starting off with the amazing experience of a woman doctor of German origin who had been born, educated and socialized in Russia the article discusses and compares higher education of women in tsarist Russia and imperial Germany. In both countries women aspired to be admitted to university, but for decades had to be content with special institutions (which did not confer academic degrees) in Russia and with the status of auditors in Germany. By discussing the particular features of female higher education and the final success of admission as regular students on an equal basis in German universities and as teaching staff in Russian ones (though women were not allowed to study there!), the article aims at raising our awareness of the complexity of different contexts. In addition to concepts of gender roles, the specific features of the educational systems and the demand for academically trained staff have to be taken into account. Only by clarifying how these (sometimes conflicting) forces were reconciled will we be able to understand the complicated processes of female admission in different countries.
description: Comparativ, Vol 21 No 4 (2011): Vermessungen der Mediengesellschaft im 20. Jahrhundert
Supplementary Materials from Reducing bias in secondary data analysis via an explore and confirm analysis workflow (ECAW): a proposal and survey of observational researchers
Creators: name: Thibault, Robert T.
name: Kovacs, Marton
name: Hardwicke, Tom E.
name: Sarafoglou, Alexandra
name: Ioannidis, John P. A.
name: Munafò, Marcus R.
Publisher: name: The Royal Society
Year: 2023
Subjects: subject: Genetics
subject: FOS: Biological sciences

description: This file contains all supplementary materials related to the manuscript "Reducing bias in secondary data analysis via an Explore and Confirm Analysis Workflow (ECAW): A survey of observational researchers". This includes (A) Deviations from the preregistration; (B) Invitation email; (C) Participant Characteristics; and (D) Figures and tables including participants who partially completed the survey.
The profibrotic role of CDA1 in modulating the down stream targets of TGF-β in a diabetic model of atherosclerosis
Creators: name: Pham., Yen
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Convergence proof for the multigrid method of the nonlocal model
Creators: name: Chen, Minghua
name: Deng, Weihua
Publisher: name: arXiv
Year: 2016
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: Recently, nonlocal models attract the wide interests of scientist. They mainly come from two applied scientific fields: peridyanmics and anomalous diffusion. Even though the matrices of the algebraic equation corresponding the nonlocal models are usually Toeplitz (denote a0 as the principal diagonal element, a1 as the trailing diagonal element, etc). There are still some differences for the models in these two fields. For the model of anomalous diffusion, a0/a1 is uniformly bounded; most of the time, a0/a1 of the model for peridyanmics is unbounded as the stepsize h tends to zero. Based on the uniform boundedness of a0/a1, the convergence of the two-grid method is well established [Chan, Chang, and Sun, SIAM J. Sci. Comput., 19 (1998), pp. 516--529; Pang and Sun, J. Comput. Phys., 231 (2012), pp. 693--703; Chen, Wang, Cheng, and Deng, BIT, 54 (2014), pp. 623--647]. This paper provides the detailed proof of the convergence of the two-grid method for the nonlocal model of peridynamics. Some special cases of the full multigrid and the V-cycle multigrid are also discussed. The numerical experiments are performed to verify the convergence.
description: 21 pages
Il “puro disegno” di Liceo, da Gentile al Liceo Matematico
Creators: name: Bolondi, Giorgio
Publisher: name: Annali online della Didattica e della Formazione Docente
Year: 2022

description: Il Liceo di Giovanni Gentile nasce da una idea ben precisa: un percorso di formazione centrato sulla cultura classica occidentale. Da questa scuola sono usciti i più importanti matematici italiani degli ultimi cent’anni. Ripercorrendo la storia di questa idea, con i suoi forti presupposti ideologici e i suoi limiti, l’articolo arriva a inquadrare l’esperienza di “Liceo Matematico” che si sta sviluppando in questi anni.
description: Annali online della Didattica e della Formazione Docente, V. 14 N. 24 (2022): Processi di insegnamento-apprendimento della Matematica: aspetti significativi
Die „Ökonomie der Aufmerksamkeit“ als heuristische Kategorie einer kulturhistorisch orientierten Mediengeschichte
Creators: name: Schildt, Axel
Publisher: name: Leipziger Universitätsverlag
Year: 2011

description: The „economy of attention” as a heuristic concept of a cultural-history oriented media history In the light of confusing amounts of available data, the question as to how attention is gained has become an important topic that should be situated in twentieth-century modernity, as an aspect of acceleration. The struggle for attention is a competitive one, since attention always constitutes one of various realizable possibilities. That is especially true for the mass media. In order to attract an audience, they had to explore the preferences of their consumers more and more accurately. Hence, a whole industry for measuring attention evolved whose new polling techniques generated specific constructions of the social, thereby structuring the imagination of social realities in media society. But while pointing to the various practices engendering trust between the media selling their products and their consumers, “attention economy” as an analytical concept blends out the influence of media actors. In their theoretical reflections, Georg Franck and others simply ignore individual agency.
description: Comparativ, Vol 21 No 4 (2011): Vermessungen der Mediengesellschaft im 20. Jahrhundert