cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Effect of the Optical Pumping and Magnetic Field on the States of Phase Separation Domains in Eu_{0.8}Cr_{0.2}Mn_2O_5
Creators: name: Golovenchits, E. I.
name: Khannanov, B. Kh.
name: Sanina, V. A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences
subject: F.2.2; I.2.7
subject: 14J60

description: The effect of optical pumping and applied magnetic field on the characteristics of ferromagnetic layers in one-dimensional superlattices is studied. At low enough temperatures, these layers correspond to phase separation domains in RMn_2O_5 and R_{0.8}Ce_{0.2}Mn_2O_5 multiferroics. The formation of such domains occurs owing to the charge ordering of Mn^{3+} and Mn^{4+} ions and to the finite probability for e_g electrons to tunnel between these pairs of ions. The volume occupied by such superlattices is rather small, and they can be treated as isolated ferromagnetic semiconductor heterostructures, spontaneously formed in the host crystal. The sequences of ferromagnetic resonances related to the superlattice layers in Eu_{0.8}Ce_{0.2}Mn_2O_5 are studied. The characteristics of these resonances give information on the properties of such layers. For the first time, it is demonstrated that the optical pumping gives rise to a new metastable state of superlattices, which can be recovered by the magnetic field cycling to the state existing before the optical pumping. It is found that the superlattices recovered by the magnetic field exist up to temperatures higher than those in as-grown crystals.
description: 12 pages, 3 figures
СТАНДАРТИЗАЦИЯ КАПСУЛ НА ОСНОВЕ  СУХОГО ЭКСТРАКТА  БЕССМЕРТНИКА САМАРКАНДСКОГО
Creators: name: Кариева, Ёқут
name: Садикова, Ранохон
name: Баратова, Малика
Publisher: name: Zenodo
Year: 2024

description: В данной статье приведены результаты по стандартизации капсул на основе сухого экстракта бессмертника самаркандского. Были проведены исследования по оценке и установлению норм таких качественных и количественных показателей как внешний вид, средняя масса капсулы и средняя масса содержимого капсулы, а также отклонения от данных показателей, распадаемость, растворение, микробиологическая чистота и количественное содержание суммы флавоноидов в пересчете на изосалипурпозид. Определение вышеуказанных показателей проводили согласно требованиям ГФ РУз I изд и ГФ РФ XIV изд. По результатам исследований по стандартизации анализируемых капсул, установлены нормы для качественных и количественных показателей капсул. Полученные данные послужат основой для разработки нормативной документации на капсулы на основе сухого экстракта бессмертника самаркандского.
The internet in the British Columbia French as a second language classroom
Creators: name: Ellis, Stefan
Publisher: name: University of British Columbia
Year: 2009

description: This study investigates the role of the Internet in teaching and learning French as a second language. In facilitating communication with francophones and access to topical information in French, the use of the Internet addresses many of the criticisms identified in prior research of the static nature of traditional computer-assisted language learning (CALL). The Internet potentially plays an important role in realizing the goals of the communicative approach in the British Columbia Core French curriculum. This study documents a variety of language learning activities that make use of the Internet's many facets, such as electronic mail, listservs, gophers, Usenet newsgroups, and World-Wide Web. Questionnaires were distributed to French teachers who either registered for an electronically-distributed course or attended a workshop on using the Internet in the French as a second language classroom. Follow-up interviews were conducted with a selection of teachers who completed and returned the questionnaire. The present study found that French teachers continue to value the Internet most for the exchange of electronic mail with francophone students. While expressing interest in other Internetbased activities, the teachers identified overriding concerns about keeping their students on-task, and about the poor quality and quantity of computing facilities at their schools. Further research should involve case studies with teachers who are implementing a variety of Internet activities over an extended term.
Casimir light in dispersive nanophotonics
Creators: name: Sloan, Jamison
name: Rivera, Nicholas
name: Joannopoulos, John D.
name: Soljačić, Marin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Time-varying optical media, whose dielectric properties are actively modulated in time, introduce a host of novel effects in the classical propagation of light, and are of intense current interest. In the quantum domain, time-dependent media can be used to convert vacuum fluctuations (virtual photons) into pairs of real photons. We refer to these processes broadly as ``dynamical vacuum effects'' (DVEs). Despite interest for their potential applications as sources of quantum light, DVEs are generally very weak, providing many opportunities for enhancement through modern techniques in nanophotonics, such as using media which support excitations such as plasmon and phonon polaritons. Here, we present a theory of DVEs in arbitrary nanostructured, dispersive, and dissipative systems. A key element of our framework is the simultaneous incorporation of time-modulation and ``dispersion'' through time-translation-breaking linear response theory. We propose a highly efficient scheme for generating entangled surface polaritons based on time-modulation of the optical phonon frequency of a polar insulator. We show that the high density of states, especially in hyperbolic polaritonic media, may enable high-efficiency generation of entangled phonon-polariton pairs. More broadly, our theoretical framework enables the study of quantum light-matter interactions in time-varying media, such as spontaneous emission, and energy level shifts.
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the wreck of the: Water Lily
Creators: name: Perks, Graeme
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: The Water Lily was built in Aberystwyth in 1834 by Lewis Roderick, and although registered at that port her sailing area was given as Gloucester to Lydney. The first master and owner in LR was W James. The Water Lily sailed to many ports on the West and South coasts of the United Kingdom and to Ireland. In 1843 she was driven ashore near Pwllheli in a storm but after unloading her damaged cargo of salt was recovered with from the shore. In 1844 the Water Lily was one of 18 vessels driven ashore at Portdinllaen but was again recovered.
Neutron electric dipole moment using lattice QCD simulations at the physical point
Creators: name: Alexandrou, C.
name: Athenodorou, A.
name: Hadjiyiannakou, K.
name: Todaro, A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We extract the neutron electric dipole moment $\vert \vec{d}_N\vert$ within the lattice QCD formalism. We analyse one ensemble of $N_f=2+1+1$ twisted mass clover-improved fermions with lattice spacing of $a \simeq 0.08 \ {\rm fm}$ and physical values of the quark masses corresponding to a pion mass $m_π \simeq 139 \ {\rm MeV}$. The neutron electric dipole moment is extracted by computing the $CP$-odd electromagnetic form factor $F_3(Q^2 \to 0)$ through small $θ$-expansion of the action. This approach requires the calculation of the topological charge for which we employ a fermionic definition by means of spectral projectors while we also provide a comparison with the gluonic definition accompanied by the gradient flow. We show that using the topological charge from spectral projectors leads to absolute errors that are more than two times smaller than those provided when the field theoretic definition is employed. We find a value of $\vert \vec{d}_N\vert = 0.0009(24) \ θ\ e \cdot {\rm fm}$ when using the fermionic definition, which is statistically consistent with zero.
description: 23 pages and 10 figures
The clustering of submillimeter galaxies detected with ALMA
Creators: name: Garcia-Vergara, Cristina
name: Hodge, Jacqueline
name: Hennawi, Joseph F.
name: Weiss, Axel
name: Wardlow, Julie
name: Myers, Adam D.
name: Hickox, Ryan
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Previous studies measuring the clustering of submillimeter galaxies (SMGs) have based their measurements on single-dish detected sources, finding evidence for strong clustering. However, ALMA has revealed that, due to the coarse angular resolution of these instruments, single-dish sources can be comprised of multiple sources. This implies that the clustering inferred from single-dish surveys may be overestimated. Here, we measure the clustering of SMGs based on the ALESS survey, an ALMA follow-up of sources previously identified in the LABOCA ECDFS Submillimeter Survey (LESS). We present a method to measure the clustering of ALMA sources that have been previously identified using single-dish telescopes, based on forward modeling both the single-dish and the ALMA observations. We constrain upper limits for the median mass of halos hosting SMGs at $1
description: 20 pages, 14 figures, Accepted for publication in ApJ
Bayesian Optimization for Ion Beam Centroid Correction
Creators: name: Ghelfi, Emma
name: Katrusiak, Alexander
name: Baartman, Rick
name: Fedorko, Wojtek
name: Kester, Oliver
name: Anele, Giordano Kogler
name: Shelbaya, Olivier
name: Tanyer, Defne
Publisher: name: arXiv
Year: 2025
Subjects: subject: Accelerator Physics (physics.acc-ph)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: An activity of the TRIUMF automatic beam tuning program, the Bayesian optimization for Ion Steering, BOIS, method has been developed to perform corrective centroid steering of beams at the TRIUMF ISAC facility. BOIS exclusively controls the steerers for centroid correction after the transverse optics have been set according to theory. The method is fully online, easy to deploy, and has been tested in low energy and postaccelerated beams at ISAC, achieving results comparable to human operators. scaleBOIS and boundBOIS are naive proof of concept solutions to preferably select beam paths with minimal steering. Repeatable and robust automated steering reduces reliance on operator expertise and operational overhead, ensuring reliable beam delivery to the experiments and thereby supporting TRIUMF's scientific mission.
description: 10 pages, 9 figures, 3 tables. Bayesian optimization applied to ion beam centroid tuning
Discovery of an 86 AU Radius Debris Ring Around HD 181327
Creators: name: Schneider, Glenn
name: Silverstone, Murray D.
name: Hines, Dean C.
name: Augereau, Jean-Charles
name: Pinte, Christophe
name: Menard, Francois
name: Krist, John
name: Clampin, Mark
name: Grady, Carol
name: Golimowski, David
name: Ardila, David
name: Henning, Thomas
name: Wolf, Sebastian
name: Rodmann, Jens
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: HST/NICMOS PSF-subtracted coronagraphic observations of HD 181327 have revealed the presence of a ring-like disk of circumstellar debris seen in 1.1 micron light scattered by the disk grains, surrounded by a di use outer region of lower surface brightness. The annular disk appears to be inclined by 31.7 +/- 1.6 deg from face on with the disk major axis PA at 107 +/-2 deg . The total 1.1 micron flux density of the light scattered by the disk (at 1.2" < r < 5.0") of 9.6 mJy +/- 0.8 mJy is 0.17% +/- 0.015% of the starlight. Seventy percent of the light from the scattering grains appears to be confined in a 36 AU wide annulus centered on the peak of the radial surface brightness (SB) profile 86.3 +/- 3.9 AU from the star, well beyond the characteristic radius of thermal emission estimated from IRAS and Spitzer flux densities assuming blackbody grains (~ 22 AU). The light scattered by the ring appears bilaterally symmetric, exhibits directionally preferential scattering well represented by a Henyey-Greenstein scattering phase function with g = 0.30 +/- 0.03, and has an azimuthally medianed SB at the 86.3 AU radius of peak SB of 1.00 +/- 0.07 mJy arcsec^-2. No photocentric offset is seen in the ring relative to the position of the central star. A low surface brightness diffuse halo is seen in the NICMOS image to a distance of ~ 4" Deeper 0.6 micron HST/ACS PSF-subtracted coronagraphic observations reveal a faint outer nebulosity, asymmetrically brighter to the North of the star. We discuss models of the disk and properties of its grains, from which we infer a maximum vertical scale height of 4 - 8 AU at the 87.6 AU radius of maximum surface density, and a total maximum dust mass of collisionally replenished grains with minimum grain sizes of ~ 1 micron of ~ 4 M(moon).
description: 45 pages, 15 figures, accepted for publication in ApJ
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the Grounding of: Water Lily (Sdchooner)
Creators: name: Davies, Gareth J.S.
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: On Dec 06 1914, the schooner Water Lily grounded at Abersoch, Wales during a storm and the crew were the crew rescued by the Abersoch lifeboat. Although reported to be have been wrecked the schooner Water Lily was refloated. On Sept 10th 1917, the schooner Water Lily while sailing from Runcorn Cheshire to Cherbourg France with a cargo of coal was stopped by U-boat UC 51 and sunk 8 miles from Pendeen Lighthouse, Cornwall.
The Star-Formation Efficiency and Density of the Disks of Spiral Galaxies
Creators: name: Zasov, A. V.
name: Abramova, O. V.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: For four well studied spiral galaxies (M33, M81, M100 and M101) we consider the dependencies of star formation rate (SFR) and star formation efficiency (SFE = SFR/M_{gas}) both on the radial distance R and on some kinematic parameters of galactic discs. To estimate SFR(R) we used a combined UV+FIR method based on the UV profiles corrected for the interstellar extinction presented by Boissier et al, 2004. It is demonstrated that the most tight correlation, similar for all four galaxies we considered, exists between the local SFE and the surface brightness (density) of discs at a given R (beyond their central regions). To account for the observed surface densities of discs in the frame of a simple conservative model of evolution of gas content (a toy model) it is necessary for the local parameter N in the Schmidt law for a disc (SFR \sim σ_{gas}^N) not to exceed unit. Only in this case it is possible to reconcile the observed dependencies σ_{gas}(R) and SFE(R) assuming a gas accretion, more intense in the inner regions of galaxies.
description: 25 pages, 9 figures
Η Ιστορία του Ελληνισμού ως πυρήνας δημιουργικής γραφής στο έπος Χρήστος Μηλιόνης του Αλέξανδρου Παπαδιαμάντη
Creators: name: Σωτηρίου, Σοφία Αλέξανδρου
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Ελληνισμός
Δημιουργική γραφή
Χρήστος Μηλιόνης, Αλέξανδρος Παπαδιαμάντης
Hellenism
Creative writing
Christos Milionis, Alexandros Papadiamantis

description: Ο Xρήστος Μηλιόνης, η ιστορική μορφή του 18ου αιώνα και η παράτολμη δράση του συνδέεται με την ιστορία του Ελληνισμού. Πρόκειται για πραγματικά συμβάντα, μία ιστορία αληθινή, που διέσωσε η προφορική παράδοση με τη μορφή δημοτικού άσματος. Τόσο το θέμα από το δημοτικό άσμα «του Χρήστου Μηλιόνη» όσο και τα ιστορικά γεγονότα σχετιζόμενα με τη ζωή του, απετέλεσαν πηγή έμπνευσης στη δημιουργική γραφή του συγγραφέα Αλέξανδρου Παπαδιαμάντη, που εμπλούτισε με αληθοφανή συμβάντα επινόησης την πλοκή του έργου του. To ιστορικό πρόσωπο και η δράση του έγιναν δημοτικό άσμα και το άσμα «προκάλεσε» την δημιουργία του μοναδικού έπους του Παπαδιαμάντη με τίτλο Χρήστος Μηλιόνης.
description: Christos Milionis, the historical figure who lived in the 18th century and his brave actions in the events are connected to the history of Hellenism. These are real events and a true story that was saved by Hellenic oral tradition in the form of a chant. This theme, the chant of Christos Milionis and the historical facts about his life and actions, was a source of inspiration for the creative writing of Alexandros Papadiamantis, who enriched his plot with incidents of his invention. This historical figure and his actions became a popular chant, which led Papadiamantis to create his unique epic novel titled Christos Milionis.
Are moving punctures equivalent to moving black holes?
Creators: name: Thornburg, Jonathan
name: Diener, Peter
name: Pollney, Denis
name: Rezzolla, Luciano
name: Schnetter, Erik
name: Seidel, Ed
name: Takahashi, Ryoji
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: When simulating the inspiral and coalescence of a binary black-hole system, special care needs to be taken in handling the singularities. Two main techniques are used in numerical-relativity simulations: A first and more traditional one ``excises'' a spatial neighbourhood of the singularity from the numerical grid on each spacelike hypersurface. A second and more recent one, instead, begins with a ``puncture'' solution and then evolves the full 3-metric, including the singular point. In the continuum limit, excision is justified by the light-cone structure of the Einstein equations and, in practice, can give accurate numerical solutions when suitable discretizations are used. However, because the field variables are non-differentiable at the puncture, there is no proof that the moving-punctures technique is correct, particularly in the discrete case. To investigate this question we use both techniques to evolve a binary system of equal-mass non-spinning black holes. We compare the evolution of two curvature 4-scalars with proper time along the invariantly-defined worldline midway between the two black holes, using Richardson extrapolation to reduce the influence of finite-difference truncation errors. We find that the excision and moving-punctures evolutions produce the same invariants along that worldline, and thus the same spacetimes throughout that worldline's causal past. This provides convincing evidence that moving-punctures are indeed equivalent to moving black holes.
description: 4 pages, 3 eps color figures; v2 = major revisions to introduction & conclusions based on referee comments, but no change in analysis or results
How correlations change the magnetic structure factor of the kagome Hubbard model
Creators: name: Kaufmann, Josef
name: Steiner, Klaus
name: Scalettar, Richard T.
name: Held, Karsten
name: Janson, Oleg
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The kagome Hubbard model (KHM) is a paradigmatic example of a frustrated two-dimensional model. While its strongly correlated regime, described by a Heisenberg model, is of topical interest due to its enigmatic prospective spin-liquid ground state, the weakly and moderately correlated regimes remain largely unexplored. Motivated by the rapidly growing number of metallic kagome materials (e.g., Mn$_3$Sn, Fe$_3$Sn$_2$, FeSn, Co$_3$Sn$_2$S$_2$, Gd$_3$Ru$_4$Al$_{12}$), we study the respective regimes of the KHM by means of three complementary numerical methods: the dynamical mean-field theory (DMFT), the dynamical vertex approximation (D$Γ$A), and determinant quantum Monte Carlo (DQMC). In contrast to the archetypal square-lattice, we find no tendencies towards magnetic ordering, as magnetic correlations remain short-range. Nevertheless, the magnetic correlations undergo a remarkable crossover as the system approaches the metal-to-insulator transition. The Mott transition itself does however not affect the magnetic correlations. Our equal-time and dynamical structure factors can be used as a reference for inelastic neutron scattering experiments on the growing family of metallic kagome materials.
description: 18 pages, 14 figures
Invariants of curves in RP^2 and R^2
Creators: name: Thompson, Abigail
Publisher: name: arXiv
Year: 2006
Subjects: subject: Geometric Topology (math.GT)
subject: FOS: Mathematics
subject: 53A04, 14H50

description: There is an elegant relation found by Fabricius-Bjerre [Math. Scand 40 (1977) 20--24] among the double tangent lines, crossings, inflections points, and cusps of a singular curve in the plane. We give a new generalization to singular curves in RP^2. We note that the quantities in the formula are naturally dual to each other in RP^2, and we give a new dual formula.
description: This is the version published by Algebraic & Geometric Topology on 19 November 2006
A Generic Two-band Model for Unconventional Superconductivity and Spin-Density-Wave Order in Electron and Hole Doped Iron-Based Superconductors
Creators: name: Han, Q.
name: Chen, Y.
name: Wang, Z. D.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Based on experimental data on the newly synthesized iron-based superconductors and the relevant band structure calculations, we propose a minimal two-band BCS-type Hamiltonian with the interband Hubbard interaction included. We illustrate that this two-band model is able to capture the essential features of unconventional superconductivity and spin density wave (SDW) ordering in this family of materials. It is found that bound electron-hole pairs can be condensed to reveal the SDW ordering for zero and very small doping, while the superconducting ordering emerges at small finite doping, whose pairing symmetry is qualitatively analyzed to be of nodal d-wave. The derived analytical formulas not only give out a nearly symmetric phase diagram for electron and hole doping, but also is likely able to account for existing main experimental results. Moreover, we also derive two important relations for a general two-band model and elaborate how to apply them to determine the band width ratio and the effective interband coupling strength from experimental data.
description: 6 pages, 4 figures, refs. added, typos corrected
Differential cross section for neutron-proton bremsstrahlung
Creators: name: Safkan, Y.
name: Akdogan, T.
name: Franklin, W. A.
name: Matthews, J. L.
name: Schmitt, W. M.
name: Zelevinsky, V. V.
name: Gram, P. A. M.
name: Taddeucci, T. N.
name: Wender, S. A.
name: Pate, S. F.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The neutron-proton bremsstrahlung process $(np \to npγ)$ is known to be sensitive to meson exchange currents in the nucleon-nucleon interaction. The triply differential cross section for this reaction has been measured for the first time at the Los Alamos Neutron Science Center, using an intense, pulsed beam of up to 700 MeV neutrons to bombard a liquid hydrogen target. Scattered neutrons were observed at six angles between 12$^\circ$ and 32$^\circ$, and the recoil protons were observed in coincidence at 12$^\circ$, 20$^\circ$, and 28$^\circ$ on the opposite side of the beam. Measurement of the neutron and proton energies at known angles allows full kinematic reconstruction of each event. The data are compared with predictions of two theoretical calculations, based on relativistic soft-photon and non-relativistic potential models.
description: 5 pages, 3 figures
Children’s talk in collaborative settings
Creators: name: Garcia, Rosamar
Publisher: name: University of British Columbia
Year: 2009

description: This study describes children's talk in collaborative settings. It illustrates conversations between students as they participate in writing, problem solving, and music composition activities. The study discusses the features of collaborative talk, describes the ways that students participate in groups, and offers a rationale for supporting the development of this speech genre in cliildren. As well, it is an account of one teacher's experience with action research. It provides commentary on shifting beliefs and their implications for practice. Using a case study design, four participants aged eight and nine years old were observed in their classroom setting. A total of seven lessons in Mathematics, Science, Language Arts and Music were recorded. Children participated in both teacher-posed problem activities and student-designed, self-directed experiences. Methods of analyzing the data were adapted from two sources: Barnes and Todd's (1977) analysis of discourse moves and Well's (1983) system of insightful observation and analysis.
Dimensional Coherence: A Unified Framework for AI, Cognition, and Natural Systems
Creators: name: Todd, Ian
Publisher: name: Zenodo
Year: 2025

description: Zipf’s law manifests across diverse complex systems—from language and neural activity to natural phenomena—suggesting a common underlying principle. This paper introduces dimensional coherence, a unifying framework that explains how information self-organizes in hyperdimensional vector spaces through entropy export dynamics. I demonstrate mathematically that these systems naturally produce Zipfian distributions with exponents near -1, precisely matching observed patterns in both natural and artificial intelligence. The framework reveals why current AI architectures based on high-dimensional vector spaces have proven so effective: they capture the same fundamental principles that govern information processing in biological neural systems. By explicitly incorporating sub-threshold information dynamics—weak signals that collectively stabilize coherent states—this framework offers new directions for AI development beyond simply scaling parameters. I establish quantitative relationships between system dimensionality, entropy dynamics, and emergent intelligence, suggesting approaches for designing more efficient, adaptive, and capable AI systems that better leverage dimensional coherence principles already operational in biological intelligence.
Quasars: What turns them off?
Creators: name: Thacker, Robert J.
name: Scannapieco, Evan
name: Couchman, H. M. P.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: (Abridged) We explore the idea that the anti-hierarchical turn-off observed in the quasar population arises from self-regulating feedback, via an outflow mechanism. Using a detailed hydrodynamic simulation we calculate the luminosity function of quasars down to a redshift of z=1 in a large, cosmologically representative volume. Outflows are included explicitly by tracking halo mergers and driving shocks into the surrounding intergalactic medium. Our results are in excellent agreement with measurements of the spatial distribution of quasars, and we detect an intriguing excess of galaxy-quasar pairs at very short separations. We also reproduce the anti-hierarchical turnoff in the quasar luminosity function, however, the magnitude of the turn-off falls short of that observed as well as that predicted by analogous semi-analytic models. The difference can be traced to the treatment of gas heating within galaxies. The simulated galaxy cluster L_X-T relationship is close to that observed for z~1 clusters, but the simulated galaxy groups at z=1 are significantly perturbed by quasar outflows, suggesting that measurements of X-ray emission in high-redshift groups could well be a "smoking gun" for the AGN heating hypothesis.
description: 16 pages, 11 figures, submitted to ApJ, comments welcomed
GUT Baryogenesis With Primordial Black Holes
Creators: name: Hooper, Dan
name: Krnjaic, Gordan
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: In models of baryogenesis based on Grand Unified Theories (GUTs), the baryon asymmetry of the universe is generated through the CP and baryon number violating, out-of-equilibrium decays of very massive gauge or Higgs bosons in the very early universe. Recent constraints on the scale of inflation and the subsequent temperature of reheating, however, have put pressure on many such models. In this paper, we consider the role that primordial black holes may have played in the process of GUT baryogenesis. Through Hawking evaporation, black holes can efficiently generate GUT Higgs or gauge bosons, regardless of the masses of these particles or the temperature of the early universe. Furthermore, in significant regions of parameter space, the black holes evaporate after the electroweak phase transition, naturally evading the problem of sphaleron washout that is normally encountered in GUT models based on $SU(5)$. We identify a wide range of scenarios in which black holes could facilitate the generation of the baryon asymmetry through the production and decays of GUT bosons.
description: 12 pages, 4 figures, 1 appendix
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the wreck of the: Weaver
Creators: name: Harwood, Sarah
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: The Weaver appears to have been wrecked in October 1859 in a severe storm that affected many ships, the Weaver was refloated subsequently the Weaver ran aground off Llanaelhaiarn on July 7th 1879 finally sinking.
Reading strategies for Japanese as a second language: A study of English and Chinese native readers
Creators: name: Furuta, Kimi
Publisher: name: University of British Columbia
Year: 2009

description: Research in second languages (L2) has identified that reading in L2 requires a reader to use both top-down processing (e.g., use of background knowledge) and bottom-up processing (e.g., letter processing), and that relying heavily on one type of processing may impede successful comprehension. However, in the area of Japanese as a Second Language (JSL), few investigations have been conducted on strategy use among JSL readers in comprehending Japanese texts. In particular, there is not enough investigation of the validity of the prevalent belief among JSL teachers that a learner who has substantial prior knowledge of Chinese characters (i.e., knows Chinese) comprehends Japanese texts far better than a learner who does not, since Chinese characters are extensively used for content words in Japanese texts. Nevertheless, transferring knowledge of Chinese characters may also be a drawback because some Japanese kanji compounds are not semantically compatible with those in Chinese. Some researchers suggest that knowledge of Chinese characters is not necessarily an advantage for successful comprehension in Japanese (e.g., Hatasa, 1992). This study examined if there are any differences in reading strategy use between the two language groups of intermediate JSL readers. It also examined the relationship between the application of the knowledge of Chinese characters to solving kanji problems and the readers' overall performance in comprehending Japanese texts. Eight university JSL learners participated in recall tasks of two Japanese passages, verbalising their thoughts during the tasks. Both qualitative and quantitative data from this case study suggest that use of Chinese knowledge does not guarantee Chinese readers successful or superior comprehension of Japanese texts: those readers must be able to identify the rhetorical structure of the passages and use it when reconstructing mental representations of the passages. Also the results suggest that use df knowledge of Chinese characters has to be accompanied by effective use of metacognitive strategies to maximise its usefulness. The results indicate that reading instruction in JSL needs to recognise the interactive nature of the reading processes and that the activities that help learners develop effective use of top-down processing and metacognitive strategies should be integrated into their instruction.
Universality of photon counting below a bifurcation threshold
Creators: name: Arndt, Lisa
name: Hassler, Fabian
Publisher: name: arXiv
Year: 2020
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: At a bifurcation point, a small change of a parameter causes a qualitative change in the system. Quantum fluctuations wash out this abrupt transition and enable the emission of quantized energy, which we term photons, below the classical bifurcation threshold. Close to the bifurcation point, the resulting photon counting statistics is determined by the instability. We propose a generic method to derive a characteristic function of photon counting close to a bifurcation threshold that only depends on the dynamics and the type of bifurcation, based on the universality of the Martin-Siggia-Rose action. We provide explicit expressions for the cusp catastrophe without conservation laws. Moreover, we propose an experimental setup using driven Josephson junctions that exhibits both a fold and a pitchfork bifurcation behavior close to a cusp catastrophe.
description: 5 pages, 2 figures
Aluminum Enhanced Metal-Poor Stars buried in the Inner Galaxy
Creators: name: Fernández-Trincado, José G.
name: Beers, Timothy C.
name: Minniti, Dante
name: Tang, Baitian
name: Villanova, Sandro
name: Geisler, Doug
name: Pérez-Villegas, Angeles
name: Vieira, Katherine
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Stars with higher aluminum and nitrogen enrichment are often the key pieces for the chemical makeup of multiple populations in almost all globular clusters (GCs). There is also compelling observational evidence that some Galactic components could be partially built from dissipated GCs. Thus, the identification of such kinds of stars among metal-poor field stars may provide insights on the composite nature of the Milky Way (MW) bulge and inner stellar halo, as well as reveal other chemical peculiarities. Here, based on APOGEE spectra, we report the discovery of 29 mildly metal-poor ([Fe/H]$\lesssim-0.7$) stars with stellar atmospheres strongly enriched in aluminum (Al-rich stars: [Al/Fe]$\gtrsim+0.5$), well above the typical Galactic levels, located within the Solar radius toward the bulge region, which lies in highly eccentric orbits ($e\gtrsim0.6$). We find many similarities for almost all of the chemical species measured in this work with the chemical patterns of GCs, so we conjecture that they have likely been dynamically ejected into the bulge and inner halo from GCs formed in situ and/or GC formed in different progenitors of known merger events experienced by the MW, such as the \textit{Gaia}-Sausage-Enceladus and/or Sequoia.
description: Accepted for publication on Astronomy & Astrophysics Letters. 11 pages, 6 figures, 2 tables
Structure and Dynamics of DNA-dendrimer complexation: Role of counterions, water and base pair sequence
Creators: name: Maiti, Prabal K.
name: Bagchi, Biman
Publisher: name: arXiv
Year: 2006
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We study sequence dependent complexation between oligonucleotides (single strand DNA) and various generation ethylene diamine (EDA) cored poly amido amide (PAMAM) dendrimers through atomistic molecular dynamics simulations accompanied by free energy calculations and inherent structure determination. Simulations reveal formation of a stable complex and provide a detailed molecular level understanding of the structure and dynamics of such a complexation. The reaction free energy surface in the initial stage is found to be funnel-like with a significant barrier arising in the late stage due to the occurrence of misfolded states of DNA. Complexation shows surprisingly strong sensitivity to the ssDNA sequence which is found to arise from a competition between enthalpic versus entropic rigidity of ssDNA.
description: 28 pages
Thermal Transport in Amorphous Graphene with Varying Structural Quality
Creators: name: Antidormi, Aleandro
name: Colombo, Luciano
name: Roche, Stephan
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: The synthesis of wafer-scale two-dimensional amorphous carbon monolayers has been recently demonstrated. This material presents useful properties when integrated as coating of metals, semiconductors or magnetic materials, such as enabling efficient atomic layer deposition and hence fostering the development of ultracompact technologies. Here we propose a characterization of how the structural degree of amorphousness of such carbon membranes could be controlled by the crystal growth temperature. We also identify how energy is dissipated in this material by a systematic analysis of emerging vibrational modes whose localization increases with the loss of spatial symmetries, resulting in a tunable thermal conductivity varying by more than two orders of magnitude. Our simulations provide some recipe to design most suitable "amorphous graphene" based on the target applications such as ultrathin heat spreaders, energy harvesters or insulating thermal barriers.
description: 35 pages
On the reliability of the fractal dimension measure of solar magnetic features and on its variation with solar cycle
Creators: name: Criscuoli, Serena
name: Rast, Mark
name: Ermolli, Ilaria
name: Centrone, Mauro
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Several studies have investigated the fractal and multifractal nature of magnetic features in the solar photosphere and its variation with the solar magnetic activity cycle. Here we extend those studies by examining the fractal geometry of bright magnetic features at higher atmospheric levels, specifically in the solar chromosphere. We analyze structures identified in CaIIK images obtained with the Precision Solar Photometric Telescopes (PSPTs) at Osservatorio Astronomico di Roma (OAR) and Mauna Loa Solar Observatory (MLSO). Fractal dimension estimates depend on the estimator employed, the quality of the images, and the structure identification techniques used. We examine both real and simulated data and employ two different perimeter-area estimators in order to understand the sensitivity of the deduced fractal properties to pixelization and image quality. The fractal dimension of bright 'magnetic' features in CaIIK images ranges between values of 1.2 and 1.7 for small and large structures respectively. This size dependency largely reflects the importance of image pixelization in the measurement of small objects. The fractal dimension of chromospheric features does not show any clear systematic variation with time over the period examined, the descending phase of solar cycle 23. These conclusions, and the analysis of both real and synthetic images on which they are based, are important in the interpretation of previously reported results.
description: 11 pages
Experimental demonstration of negative refractionwith 3D locally resonant acoustic metafluids
Creators: name: Tallon, Benoit
name: Kovalenko, Artem
name: Poncelet, Olivier
name: Aristégui, Christophe
name: Mondain-Monval, Olivier
name: Brunet, Thomas
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Negative refraction of acoustic waves is demonstrated through underwater experiments conducted at ultrasonic frequencies on a 3D locally resonant acoustic metafluid made of soft porous silicone-rubber micro-beads suspended in a yield-stress fluid. By measuring the refracted angle of the acoustic beam transmitted through this metafluid shaped as a prism, we determine the acoustic index to water according to Snell's law. These experimental data are then compared with an excellent agreement to calculations performed in the framework of Multiple Scattering Theory showing that the emergence of negative refraction depends on the volume fraction $Φ$ of the resonant micro-beads. For diluted metafluid ($Φ=3\%$), only positive refraction occurs whereas negative refraction is demonstrated over a broad frequency band with concentrated metafluid ($Φ=17\%$).
description: 6 pages, 4 figures
Προσπάθειες σύνθεσης των φυσικών προϊόντων Μαρινεοσίνη Α και Β
Creators: name: Θυσιάδης, Σάββας Χρυσόστομου
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Μαρινεοσίνη
Σύνθεση Φυσικών Προϊόντων
Σπειρο-αμινάλη
Marineosine
Synthesis of Natural Products
Spiro-aminals

description: Στην παρούσα μεταπτυχιακή εργασία έγινε προσπάθεια σύνθεσης των φυσικών προϊόντων Μαρινεοσίνη Α και Β μέσω μιας σύντομης συνθετικής οδού ξεκινώντας από απλές πρώτες ύλες. Στην συνθετική προσέγγιση χρησιμοποιήθηκαν αντιδράσεις ‘κλειδιά’ όπως η ολεφινοποίηση Horner-Wadsworth-Emmons, η αντίδραση σύζευξης Sonogashira. Στην προσπάθεια σχηματισμού του σπειροκυκλικού τμήματος των Μαρινεοσινών χρησιμοποιήθηκε ένα ευρύ φάσμα αντιδράσεων καταλυόμενες από μέταλλα (όπως Pd, Au κτλ.) με ενδιαφέροντα αποτελέσματα. Τέλος, επετεύχθη προσθήκη αμιδικού αζώτου σε τριπλό δεσμό προς τον σχηματισμό του αμιναλικού πενταμελούς δακτυλίου.
description: In this study, we demonstrate a synthetic approach towards the total synthesis of natural products Marineosines A and B. The ‘key’ reactions used in this synthetic approach include Horner-Wadsworth-Emmons and Sonogashira reactions. We also studied several metals in an effort to form the spirobicyclic ring (such as Pd, Au etc.). Finally, the hydroamidation reaction was attempted to form the spiroaminal moiety on the five membered ring.
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the wreck of the: William Keith
Creators: name: Perks, Graeme
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: The William Keith, a schooner of 99 tons was built in 1859 by Rees Jones at Port Dinorwic for the first owner Griffith Dedwith who was also the master. William Keith sailed between Porthmadog Portugal, Spain, the continent, Baltic and both coasts of Scotland. The outward voyages usually carried slates, or coal with cargo's sourced for the return in the North of England from the Baltic. The William Keith was blown onto the Bar at Barmouth in 1860 but was re-floated after assistance from the RNLI. The William Keith continued until 1876 when she was sold to another owner, master Rees Jones when she mainly carried slates to London, returning with cargo often cement for Dublin. She also made some Baltic voyages. She was repaired after mishaps a few times before being sold on the death of the owner in 1905 to Messrs Kinch of Arklow. The William Keith was intended to carry coal to Ireland but in July 1906 she was in collision with a Swansea steamer Abermaed in fog and sank with the loss of two lives. A BOT enquiry found the steamer at fault.
Magnetic braking of accreting T Tauri stars: Effects of mass accretion rate, rotation, and dipolar field strength
Creators: name: Ireland, Lewis G.
name: Zanni, Claudio
name: Matt, Sean P.
name: Pantolmos, George
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The rotational evolution of accreting pre-main-sequence stars is influenced by its magnetic interaction with its surrounding circumstellar disk. Using the PLUTO code, we perform 2.5D magnetohydrodynamic, axisymmetric, time-dependent simulations of star-disk interaction---with an initial dipolar magnetic field structure, and a viscous and resistive accretion disk---in order to model the three mechanisms that contribute to the net stellar torque: accretion flow, stellar wind, and magnetospheric ejections (periodic inflation and reconnection events). We investigate how changes in the stellar magnetic field strength, rotation rate, and mass accretion rate (changing the initial disk density) affect the net stellar torque. All simulations are in a net spin-up regime. We fit semi-analytic functions for the three stellar torque contributions, allowing for the prediction of the net stellar torque for our parameter regime, and the possibility of investigating spin-evolution using 1D stellar evolution codes. The presence of an accretion disk appears to increase the efficiency of stellar torques compared to isolated stars, for cases with outflow rates much smaller than accretion rates, because the star-disk interaction opens more of the stellar magnetic flux compared to that from isolated stars. In our parameter regime, a stellar wind with a mass loss rate of $\approx 1 \%$ of the mass accretion rate is capable of extracting $\lesssim 50 \%$ of the accreting angular momentum. These simulations suggest that achieving spin-equilibrium in a representative T Tauri case within our parameter regime, e.g., BP Tau, would require a wind mass loss rate of $\approx 25\%$ of the mass accretion rate.
description: 26 pages, 14 figures
Merging of single-particle levels and non-Fermi-liquid behavior of finite Fermi systems
Creators: name: Khodel, V. A.
name: Clark, J. W.
name: Li, Haochen
name: Zverev, M. V.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We examine the problem of finite Fermi systems having a degenerate single-particle spectrum and show that the Landau approach, applied to such a system, admits the possibility of merging single-particle levels. It is demonstrated that the opportunity for this behavior is widespread in quantum many-body systems. The salient feature of the phenomenon is the occurrence of nonintegral quasiparticle occupation numbers, leading to a radical alteration of the standard quasiparticle picture. Implications of this alteration are considered for nuclear, atomic, and solid-state systems.
description: 5 pages, 1 figure
Welsh Wreck Web Research Project (North Cardigan Bay). On-line research into the wreck of the: Woodman of Waterford
Creators: name: Perks, Graeme
Publisher: name: Archaeology Data Service
Year: 2024

description: Welsh Wreck Web Research Project unpublished report series, 1
description: The Woodman was a schooner built in Palnackie Kirkcudbrightshire by Alexander Dick and used as a coaster in mainly western Scotland as far north as the Orkney's and into England as far south as Runcorn. Woodman carried a complete range of cargo's from Salt to railway chairs. The complete 64 shares in Woodman were sold in 1861 and it started travelling as far as the south coast and Ireland. This continued under later owners when the Woodman travelled mainly between southern Ireland and south Wales. The Woodman produced few newspaper reports of mishaps until she was based in Ireland and then she was involved in some collisions and a court case where the crew had not been paid in full. The Woodman foundered in a severe storm near Aberporth in 1883 when the crew were rescued by rocket apparatus and a bravery medal was awarded.