cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Quantum oscillations from a pair-density wave
Creators: name: Caplan, Yosef
name: Orgad, Dror
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: A pair-density wave state has been suggested to exist in underdoped cuprate superconductors, with some supporting experimental evidence emerging over the past few years from scanning tunneling spectroscopy. Several studies have also linked the observed quantum oscillations in these systems to a reconstruction of the Fermi surface by a pair-density wave. Here, we show, using semiclassical analysis and numerical calculations, that a Fermi pocket created by first-order scattering from a pair-density wave cannot induce such oscillations. In contrast, pockets resulting from second-order scattering can cause oscillations. We consider the effects of a finite pair-density wave correlation length on the signal, and demonstrate that it is only weakly sensitive to disorder in the form of $π$-phase slips. Finally, we discuss our results in the context of the cuprates and show that a bidirectional pair-density wave may produce observed oscillation frequencies.
description: 12 pages, 9 figures
Supplementary methods and results from A new terrestrial paleoenvironmental record from the Bering Land Bridge and context for human dispersal
Creators: name: Wooller, Matthew J.
name: Saulnier-Talbot, Émilie
name: Potter, Ben A.
name: Belmecheri, Soumaya
name: Bigelow, Nancy
name: Choy, Kyungcheol
name: Cwynar, Les
name: Davies, Kimberly
name: Graham, Russ
name: Kurek, Josh
name: Langdon, Peter
name: Medeiros, Andrew
name: Rawcliffe, Ruth
name: Wang, Yue
name: Williams, John W.
Publisher: name: The Royal Society
Year: 2018

description: Supplementary methods and results
Electron-Hole Symmetry and Magnetic Coupling in Antiferromagnetic LaOFeAs
Creators: name: Yin, Z. P.
name: Lebègue, S.
name: Han, M. J.
name: Neal, B.
name: Savrasov, S. Y.
name: Pickett, W. E.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: When either electron or hole doped at concentrations $x\sim 0.1$, the LaOFeAs family displays remarkably high temperature superconductivity with T$_c$ up to 55 K. In the most energetically stable $\vec Q_M = (π,π)$ antiferromagnetic (AFM) phase comprised of tetragonal-symmetry breaking alternating chains of aligned spins, there is a deep pseudogap in the Fe 3d states centered at the Fermi energy, and very strong magnetophonon coupling is uncovered. Doping (of either sign) beyond $x \sim 0.1$ results in Fe 3d heavy mass carriers ($m^*\sim 4-8$) with a large Fermi surface. Calculated Fe-Fe transverse exchange couplings $J_{ij}(R)$ reveal that exchange coupling is strongly dependent on the AFM symmetry and Fe-As distance.
description: 5 pages, 5 figures, submitted to prl
The relationship of teachers' expectations and academic learning time in grade six physical education classes
Creators: name: Cousineau, William J.
Publisher: name: University of British Columbia
Year: 2010

description: The purpose of this study was to investigate the relationship between teachers' expectations of performance, teacher training, and student gender, with student achieved Academic Learning Time (A.L.T.) of grade six students. To examine the following relationships four main hypotheses were generated. It was hypothesized that: 1 There would be a positive relationship between A.L.T. and teachers' expectations of performance in Physical Education. 2 Teachers with Physical Education majors would have greater A.L.T. than those with Physical Education minors, or generalist classroom teachers. 3 There would be no difference in A.L.T. totals between student gender. 4 There would be less student off-task time in Physical Education majors classes, than in the Physical Education minors, and the generalist teachers'. This study also examines the relationship between teachers' perception of student effort, student grades in physical education, and student achieved Academic Learning Time. Finally, it was possible to investigate how student expectations of performance are developed by teachers in Physical Education. Six, grade six, classes taught by male teachers were selected for observation in the study. Two P.E. majors, two P.E. minors, and two generalist teachers' classes were observed. Each of these teachers conducted a rank-ordering of students in their class, based on their expectation of student performance. From this rank ordering, six students from each class were selected for observation during the study. Each class was observed three times, using the Academic Learning Time Version II instrument to collect data. At the conclusion of the study, teachers were also asked to submit student grades for the first and second term, rate student effort over the three observed lessons, and complete a teacher demographic information sheet. Results indicated that a positive relationship existed between teachers' expectancy and A.L.T.. It was found that P.E. majors had higher A.L.T. than did P.E. minors, or generalist teachers. No significant difference was found between student gender groups. Differences in off-task time levels were not noted between teacher training groups. A significant relationship was found between student perceived effort and student A.L.T.. Finally, it was indicated that teachers primarily use student ability and skill level in determining students' expectancy level. Recommendations for future research on this topic suggest that a larger sample size be used and that lesson and activity structure be controlled in comparative A.L.T. studies. It appears that more research is needed to substantiate the relationship between A.L.T. and teacher training, and the relationship between student achievement and A.L.T..
The branch processes of vortex filaments and Hopf Invariant Constraint on Scroll Wave
Creators: name: Zhu, Tao
name: Ren, Ji-Rong
name: Mo, Shu-Fan
Publisher: name: arXiv
Year: 2008
Subjects: subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: In this paper, by making use of Duan's topological current theory, the evolution of the vortex filaments in excitable media is discussed in detail. The vortex filaments are found generating or annihilating at the limit points and encountering, splitting, or merging at the bifurcation points of a complex function $Z(\vec{x},t)$. It is also shown that the Hopf invariant of knotted scroll wave filaments is preserved in the branch processes (splitting, merging, or encountering) during the evolution of these knotted scroll wave filaments. Furthermore, it also revealed that the "exclusion principle" in some chemical media is just the special case of the Hopf invariant constraint, and during the branch processes the "exclusion principle" is also protected by topology.
description: 9 pages, 5 figures
Photoionization of negatively charged NV centers in diamond: theory and ab initio calculations
Creators: name: Razinkovas, Lukas
name: Maciaszek, Marek
name: Reinhard, Friedemann
name: Doherty, Marcus W.
name: Alkauskas, Audrius
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Computational Physics (physics.comp-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We present ab-initio calculations of photoionization thresholds and cross sections of the negatively charged nitrogen-vacancy (NV) center in diamond from the ground $^{3}\!A_2$ and the excited $^{3}\!E$ states. We show that after the ionization from the $^{3}\!E$ level the NV center transitions into the metastable $^{4}\!A_2$ electronic state of the neutral defect. We reveal how spin polarization of $\mathrm{NV}^{-}$ gives rise to spin polarization of the $^{4}\!A_2$ state, providing an explanation of electron spin resonance experiments. We obtain smooth photoionization cross sections by employing dense $k$-point meshes for the Brillouin zone integration together with the band unfolding technique to rectify the distortions of the band structure induced by artificial periodicity of the supercell approach. Our calculations provide a comprehensive picture of photoionization mechanisms of $\mathrm{NV}^{-}$. They will be useful in interpreting and designing experiments on charge-state dynamics at NV centers. In particular, we offer a consistent explanation of recent results of spin-to-charge conversion of NV centers.
description: 14 pages, 9 figures
How common are long Gamma-Ray Bursts in the Local Universe?
Creators: name: Chapman, Robert
name: Tanvir, Nial R.
name: Priddey, Robert S.
name: Levan, Andrew J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The two closest Gamma-Ray Bursts so far detected (GRBs 980425 & 060218) were both under-luminous, spectrally soft, long duration bursts with smooth, single-peaked light curves. Only of the order of 100 GRBs have measured redshifts, and there are, for example, 2704 GRBs in the BATSE catalogue alone. It is therefore plausible that other nearby GRBs have been observed but not identified as relatively nearby. Here we search for statistical correlations between BATSE long duration GRBs and galaxy samples with recession velocities v <= 11,000 km/s (z = 0.0367, ~ 155 Mpc) selected from two catalogues of nearby galaxies. We also examine the correlations using burst sub-samples restricted to those with properties similar to the two known nearby bursts. Our results show correlation of the entire long GRB sample to remain consistent with zero out to the highest radii considered whereas a sub-sample selected to be low fluence, spectrally soft, with smooth single-peaked light curves (177 bursts) demonstrates increased correlation with galaxies within ~ 155 Mpc. The measured correlation (28% +/- 16% of the sample) suggests that BATSE observed between 2 and 9 long duration GRBs per year similar to, and from within similar distances to GRBs 980425 and 060218. This implies an observed local rate density (to BATSE limits) of 700 +/- 360 Gpc^{-3}yr^{-1} within 155 Mpc.
description: 6 pages, 4 figures. Accepted for publication in MNRAS
A Sustainable Concept for Permafrost Thermal Stabilization
Creators: name: Loktionov, Egor
name: Sharaborova, Elizaveta
name: Shepitko, Taissia
Publisher: name: arXiv
Year: 2021
Subjects: subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Although permafrost thermal stabilization systems have been used for a long time already, they have always had shortcomings and limitations of performance which have become even more pronounced in the warming climate. Those could be overcome to some extent, but at high cost mainly defined by need in energy supply. We have suggested a novel concept combining improved energy efficiency and solar power to ensure significant reduction of the thawing layer (to 20 cm order). We have performed calculations for the broad range of permafrost conditions to compare traditional methods for thermal stabilization and their combination to the suggested concept. The latter only has ensured minimum thawing layer over summer even at the southern edge of permafrost extent. The importance of minimum thawing layer is discussed in terms of chemical and biological safety in the area of human activities. The layout for glaciers protection has also been considered. Estimated cost of the concept implementation (ca. 180 USD/m2) is just slightly higher than for widely used thermosyphons while providing much better technical performance and unique possibilities for revenue by selling (not wasting) heat and excessive electricity up to 70 USD /(m2yr).
title: Tensor network simulations of open quantum systems
Creators: name: Kilda, Dainius
Publisher: name: University of St Andrews
Year: 2020

description: The nonequilibrium effects of dissipation and drive play a key role in an immense variety of nanoscale and mesoscale quantum systems. To understand the behaviour of open quantum systems, we need accurate methods that capture the influence of the environment on the system, while managing the exponentially large Hilbert space required to describe the system. Tensor network algorithms offer an efficient way to approach this challenge. In this thesis, we develop and apply tensor network techniques to study the dynamics and steady states of various open quantum systems. The first part of the thesis focuses on the driven dissipative many body physics in coupled cavity arrays described by Born-Markov master equations. We extend transfer matrix product operator methods to Liouvillian dynamics, and utilize them to compute dynamical correlation functions and fluorescence spectrum of an infinite coupled cavity array in 1D. We also investigate thermalization, and observe the emergence of a quasi-thermal steady state with a negative effective temperature. In another study, we use infinite projected entangled pair state (iPEPS) methods to compute steady states of coupled cavity lattices in 2D. We find that a straightforward adaptation of iPEPS to Liouvillian dynamics is unstable, contradicting a recent publication in the field. The second part investigates more general systems involving strong couplings and structured environments that induce non-Markovian dynamics. We develop a powerful time-evolving matrix product operator (TEMPO) algorithm that builds on Feynman-Vernon influence functional formalism, and uses matrix product states (MPS) to represent the temporal non-Markovian correlations efficiently. We apply TEMPO to study the localization phase transition of the spin-boson model and the dynamics of two spatially separated two-level systems coupled to a common environment. Finally, we propose the Toblerone TEMPO algorithm, which extends TEMPO to many-body systems interacting with general bosonic environments.
First Order Phase Transition and Superconductivity in BaNi2As2 Single Crystals
Creators: name: Ronning, F.
name: Kurita, N.
name: Bauer, E. D.
name: Scott, B. L.
name: Park, T.
name: Klimczuk, T.
name: Movshovich, R.
name: Thompson, J. D.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We report the synthesis and physical properties of single crystals of stoichiometric BaNi2As2 that crystalizes in the ThCr2Si2 structure with lattice parameters a = 4.112(4) Åand c = 11.54(2) Å. Resistivity and heat capacity show a first order phase transition at T_0 = 130 K with a thermal hysteresis of 7 K. The Hall coefficient is weakly temperature dependent from room temperature to 2 K where it has a value of -4x10^{-10} Ω-cm/Oe. Resistivity, ac-susceptibility, and heat capacity find evidence for bulk superconductivity at T_c = 0.7 K. The Sommerfeld coefficient at T_c is 11.6 \pm 0.9 mJ/molK^2. The upper critical field is anisotropic with initial slopes of dH_{c2}^{c}/dT = -0.19 T/K and dH_{c2}^{ab}/dT = -0.40 T/K, as determined by resistivity.
description: Published version: 4 pages, 4 figures
Pointwise decay for semilinear wave equations on Kerr spacetimes
Creators: name: Tohaneanu, Mihai
Publisher: name: arXiv
Year: 2021
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: In this article we prove optimal pointwise bounds for solutions to the semilinear wave equation with integer powers $p\geq 3$ on Kerr backgrounds with small angular momentum and small initial data.
description: 19 pages, acknowledgments and minor mistakes corrected
Quantum glass phases in the disordered Bose-Hubbard model
Creators: name: Sengupta, Pinaki
name: Haas, Stephan
Publisher: name: arXiv
Year: 2007
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: The phase diagram of the Bose-Hubbard model in the presence of off-diagonal disorder is determined using Quantum Monte Carlo simulations. A sequence of quantum glass phases intervene at the interface between the Mott insulating and the Superfluid phases of the clean system. In addition to the standard Bose glass phase, the coexistence of gapless and gapped regions close to the Mott insulating phase leads to a novel Mott glass regime which is incompressible yet gapless. Numerical evidence for the properties of these phases is given in terms of global (compressibility, superfluid stiffness) and local (compressibility, momentum distribution) observables.
Studies of Effects of Current on Exchange-Bias: A Brief Review
Creators: name: Bass, J.
name: Sharma, A.
name: Wei, Z.
name: Tsoi, M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: MacDonald and co-workers recently predicted that high current densities could affect the magnetic order of antiferromagnetic (AFM) multilayers, in ways similar to those that occur in ferromagnetic (F) multilayers, and that changes in AFM magnetic order can produce an antiferromagnetic Giant Magnetoresistance (AGMR). Four groups have now studied current-driven effects on exchange bias at F/AFM interfaces. In this paper, we first briefly review the main predictions by MacDonald and co-workers, and then the results of experiments on exchange bias that these predictions stimulated.
description: 8 pages, 5 figures
Nature of Stripes in the Generalized t-J Model Applied to The Cuprate Superconductors
Creators: name: Yang, Kai-Yu
name: Chen, Wei-Qiang
name: Rice, T. M.
name: Sigrist, M.
name: Zhang, Fu-Chun
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Recent transport properties on the stripe phase in La$_{\text{1.875}}$Ba$_{\text{01.25}}$CuO$_{\text{4}}$ by Li \textit{et al.} found 2-dimensional superconductivity over a wide temperature range including a Berezinski-Kosterlitz-Thouless transition at a temperature T=16K, with 3-dimensional superconducting (SC) ordering only at T=4K. These results contradict the long standing belief that the onset of superconductivity is suppressed by stripe ordering and suggest coexistence of stripe and SC phases. The lack of 3-D superconducting order above T=4K requires an antiphase ordering in the SC state to suppress the interlayer Josephson coupling as proposed by Berg \textit{et al.}. Here we use a renormalized mean field theory for a generalized t-J model to examine in detail the energetics of the spin and charge stripe ordered SC states including possible antiphase domains in the SC order. We find that the energies of these modulated states are very close to each other and that the anisotropy present in the low temperature tetragonal crystal structure favors stripe resonating valence bond states. The stripe antiphase SC states are found to have energies very close,but always above, the ground state energy which suggests additional physical effects are responsible for their stability.
description: 11 pages, 9 figures, 1 table, New J. Phys. 11 055053 (2009)
Morphological effects on surface plasmon polaritons at the planar interface of a metal and a columnar thin film The Planar Interface Of A Metal And A Columnar Thin Film
Creators: name: Polo, John A.
name: Lakhtakia, Akhlesh
Publisher: name: arXiv
Year: 2007
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Surface plasmon polaritons (SPPs) at the interface of a columnar thin film (CTF) and metal exist over a range of propagation directions relative to the morphology of the CTF which depends on the tilt of the columns in the CTF. The phase speed of the SPP wave varies mainly as a function of the tilt of the CTF columns. Both the confinement of the SPP wave to the interface and the decay of the SPP wave along the direction of propagation depend strongly on the direction of propagation relative to the morphologically significant plane of the CTF. The greater the columnar tilt in relation to the interface, the shorter is the range of propagation. Because of its porosity and the ability to engineer this biaxial dielectric material, the CTF-metal interface may be more attractive than traditional methods of producing SPPs.
QCD Splitting/Joining Functions at Finite Temperature in the Deep LPM Regime
Creators: name: Arnold, Peter
name: Dogan, Caglar
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: There exist full leading-order-in-alpha_s numerical calculations of the rates for massless quarks and gluons to split and join in the background of a quark-gluon plasma through hard, nearly collinear bremsstrahlung and inverse bremsstrahlung. In the limit of partons with very high energy E, where the physics is dominated by the Landau-Pomeranchuk-Migdal (LPM) effect, there are also analytic leading-log calculations of these rates, where the logarithm is ln(E/T). We extend those analytic calculations to next-to-leading-log order. We find agreement with the full result to within roughly 20% for E(less) >~ 10 T, where E(less) is the energy of the least energetic parton in the splitting/joining process. We also discuss how to account for the running of the coupling constant in the case that E/T is very large. Our results are also applicable to isotropic non-equilibrium plasmas if the plasma does not change significantly over the formation time associated with particle splitting.
description: 20 pages, 6 figures. Changes from v3: Typos fixed in the subscripts of various Casimir factors
Subgap states at ferromagnetic and spiral-ordered magnetic chains in two-dimensional superconductors. II. Topological classification
Creators: name: Carroll, C. J. F.
name: Braunecker, B.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We investigate the topological classification of the subgap bands induced in a two-dimensional superconductor by a densely packed chain of magnetic moments with ferromagnetic or spiral alignments. The wave functions for these bands are composites of Yu-Shiba-Rusinov-type states and magnetic scattering states and have a significant spatial extension away from the magnetic moments. We show that this spatial structure prohibits a straightforward extraction of a Hamiltonian useful for the topological classification. To address the latter correctly we construct a family of spatially varying topological Hamiltonians for the subgap bands adapted for the broken translational symmetry caused by the chain. The spatial dependence in particular captures the transition to the topologically trivial bulk phase when moving away from the chain by showing how this, necessarily discontinuous, transition can be understood from an alignment of zeros with poles of Green's functions. Through the latter the topological Hamiltonians reflect a characteristic found otherwise primarily in strongly interacting systems.
description: 15 pages, 8 figures. This is Part II of manuscript at arXiv:1709.06093 and covers topological classification
Variations in soil bacterial communities and putative functions in a sugarcane soil following five years of chemical fertilization
Creators: name: Wu, Qihua
name: Li, Shuang
name: Huang, Zhongxing
name: Wang, Qing
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Microbiology
subject: FOS: Biological sciences
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: Developmental Biology
subject: Cancer
subject: Plant Biology

description: Chemical fertilizers are often applied to increase soil nutrient contents and improve crop yields. However, the impact of chemical fertilizers on abiotic and biotic characteristics of soil is unclear. Here, we investigated the variations in soil chemical properties and bacterial communities of sugarcane soil after a five-year chemical fertilization period with five different regimes, namely, Control (no fertilizer), PK (phosphorus plus potassium fertilizer), NK (nitrogen plus potassium fertilizer), NP (nitrogen plus potassium fertilizer), and NPK (combined nitrogen, phosphorus plus potassium fertilizer). We found that N-addition fertilizer treatments resulted in lower bacterial biodiversity as estimated by Chao1 and Shannon’s indexes. Proteobacteria, Acidobacteria, Chloroflexi, and Actinobacteria were the predominant phyla in all of the fertilizer treatments. The concentrations of different N forms (TN, NH4+-N, and NO3–N) were the most important factors in shaping bacterial community structure. Functional groups involved in carbon, nitrogen, and sulfur cycling significantly increased or decreased with chemical N-related fertilizer treatments (NK, NP, and NPK). The community composition and functions related to element cycling of soil bacteria were strongly affected by N-containing fertilizer treatments. The results suggest that bacterial communities in sugarcane soil may have been phylogenetically and functionally altered in response to chemical fertilization.
The Agricultural Economy of Nigeria
Creators: name: Skinner, Snider W.
name: Skinner, Snider W.
Publisher: name: Unknown
Year: 1972
Subjects: subject: Agricultural and Food Policy
subject: Crop Production/Industries
subject: International Development
subject: International Relations/Trade
subject: Livestock Production/Industries
subject: Nigeria
subject: agricultural production
subject: agricultural trade
subject: cocoa
subject: peanuts
subject: oil palm produce
subject: rubber
subject: cotton
subject: livestock

description: Nigeria, the most populous country in Africa, has an economy based on production of raw materials, chiefly agricultural commodities and petroleum. Important agricultural exports include cocoa, peanuts, palm kernels, rubber, cotton, and hides and skins. Production of large quantities of yams, cassava, cocoyams , sorghum, millet, plantains and bananas, corn, edible cowpeas , palm oil, kolanuts , and other crop and livestock products enable the country to be largely self-sufficient for food. Major food imports include wheat, milk and cream, and sugar. Agricultural imports from the United States include wheat and flour, dried milk and cream, cereal preparations, and tobacco.
S_4 Flavor Symmetry Embedded into SU(3) and Lepton Masses and Mixing
Creators: name: Koide, Yoshio
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Based on an assumption that an S_4 flavor symmetry is embedded into SU(3), a lepton mass matrix model is investigated. A Frogatt-Nielsen type model is assumed, and the flavor structures of the masses and mixing are caused by VEVs of SU(2)_L-singlet scalars ϕ_u and ϕ_d which are nonets (8+1) of the SU(3) flavor symmetry, and which are broken into 2+3+3' and 1 of S_4. If we require the invariance under the transformation (ϕ^{(8)},ϕ^{(1)}) \to (-ϕ^{(8)},+ϕ^{(1)}) for the superpotential of the nonet field ϕ^{(8+1)}, the model leads to a beautiful relation for the charged lepton masses. The observed tribimaximal neutrino mixing is understood by assuming two SU(3) singlet right-handed neutrinos ν_R^{(\pm)} and an SU(3) triplet scalar χ.
description: 12 pages, no figure, to appear on JHEP
Diffeomorphism symmetry effect on the O(N ) universality class
Creators: name: Costa, H. A. S.
name: Carvalho, P. R. S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We probe the effect of diffeomorphism symmetry on the critical exponents values for massive O($N$) $λϕ^{4}$ scalar field theories in curved spacetime. We apply field-theoretic renormalization group tools, where we use only momentum coordinates as opposed to the earlier standard procedure with both space and momentum coordinates, for computing analytically the critical exponents up to three-loop order for one of them and up to two-loop level for the remaining ones. We found that the curved spacetime critical exponents are the same as their flat spacetime counterparts, at least up to the level considered. At the conclusions we present the physical interpretation for the results.
description: 12 pages, 14 figures
Low energy theorem for virtual Compton scattering and generalized sum rules of the nucleon
Creators: name: Gorchtein, M.
name: Szczepaniak, A. P.
Publisher: name: arXiv
Year: 2008
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: We formulate the low energy theorem for virtual Compton scattering off a nucleon and examine its consequences for generalized nucleon polarizabilites. As a result of a new, model independent definition of the low energy limit for VVCS reaction, all generalized sum rules of the nucleon have continuous limit for real photons and obtain contributions from the $t$-channel that were not included previously.
description: 4 pages, 2 figures, revtex4
Enabling News Consumers to View and Understand Biased News Coverage: A Study on the Perception and Visualization of Media Bias
Creators: name: Spinde, Timo
name: Hamborg, Felix
name: Donnay, Karsten
name: Becerra, Angelica
name: Gipp, Bela
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences

description: Traditional media outlets are known to report political news in a biased way, potentially affecting the political beliefs of the audience and even altering their voting behaviors. Many researchers focus on automatically detecting and identifying media bias in the news, but only very few studies exist that systematically analyze how theses biases can be best visualized and communicated. We create three manually annotated datasets and test varying visualization strategies. The results show no strong effects of becoming aware of the bias of the treatment groups compared to the control group, although a visualization of hand-annotated bias communicated bias instances more effectively than a framing visualization. Showing participants an overview page, which opposes different viewpoints on the same topic, does not yield differences in respondents' bias perception. Using a multilevel model, we find that perceived journalist bias is significantly related to perceived political extremeness and impartiality of the article.
The spectrum of interacting metallic carbon nanotubes: Exchange effects and universality
Creators: name: Mayrhofer, Leonhard
name: Grifoni, Milena
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The low energy spectrum of finite size metallic single-walled carbon nanotubes SWNTs) is determined. Starting from a tight binding model for the $p_{z}$ electrons, we derive the low energy Hamiltonian containing all relevant scattering processes resulting from the Coulomb interaction, including the short ranged contributions becoming relevant for small diameter tubes. In combination with the substructure of the underlying honeycomb lattice the short ranged processes lead to various exchange effects. Using bosonization the spectrum is determined. We find that the ground state is formed by a spin 1 triplet, if $4n+2$ electrons occupy the SWNT and the branch mismatch is smaller than the exchange splitting. Additionally, we calculate the excitation spectra for the different charge states and find the lifting of spin-charge separation as well as the formation of a quasi-continuum at higher excitation energies.
description: European Physical Journal B (2008) in press
The right of prisoners to education
Creators: name: Bastion, Arlene
Publisher: name: University of British Columbia
Year: 2010

description: Punishment is an acknowledged method of enforcing the law. Forms of punishment may differ, but the main aims remain the same—first, to discourage transgression of the law, thus maintaining order in society. Second, it is hoped, by some at least, that prisoners will be reformed by or during their punishment. This dissertation raises questions about the status and legal rights of individuals who are subject to the dominant form of punishment in Canada—incarceration. The questions are: Can prisoners continue to be regarded as persons and right-holders during incarceration? Can prisoners, then, have a right to education? If so, should such a right be made a legal right? The answer one gives to these questions clearly has important bearings on the status of prisoners during their incarceration. It is argued that prisoners retain their status as persons while incarcerated, that they do have rights, in particular the right to education, and that such a right should be made a legal right. Justice dictates that only relevant differences or just cause can provide acceptable justification for withholding rights from prisoners. That punishment is being inflicted on certain persons does not offer/provide adequate grounds for denying their right to education. Indeed, a legal right to education is warranted to ensure their access to education. Thus, the first proposition is that apart from the loss of rights necessary to protect society and the prison, and in order to fulfil the criteria of punishment, prisoners continue to hold rights held by other persons, in particular the right to education. This position is defended by considering arguments that prisoners have a moral right to education. These are: 1. The Argument from Incarceration 2. The Argument from The Effects of Punishment 3. The Argument from Punishment of Persons 4. The Argument from Fraternal Obligation 5. The Argument from Social Effects 6. The Argument from Benefits to the Collective 7. The Argument from Equality The second proposition that this right ought to be made a legal right rests essentially on three premises: 1. That education can contribute to the successful achievement of the goals of incarceration. 2. However, education is not considered a priority. 3. As it now stands, there is no effective way to enforce and sustain education in prisons. With a legal right to education, prisoners would have some basis for objecting to inadequate educational facilities and opportunities. A legal right would safeguard fair treatment and ensure equal opportunities to education.
Core and variable components in prokaryotic genomes
Creators: name: Rocco, Francesco
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2011

description: Acinetobacter baumannii and Stenotrophomonas maltophilia are opportunistic pathogens responsable for several hospital-acquired infections. We performed Extensive comparative analyses were performed in silico to elucidate the cromosomal organization of both species, and identify core and variable genome component in each. In the case of S. maltophilia, the genomes of strains isolated from the blood of a cancer patient (K279a strain) and the poplar Populus trichocarpa (R551-3 strain) have been compared. The analyzed chromosomes exhibit extensive synteny and 3620 homologous genes are located at the same relative position in the two strains. However, the R551-3 and the K279a chromosomes vary significantly, as they contain 13% and 19% of specific DNAs sequences, respectively. This DNA fraction is largely represented by unrelated foreign DNA segments or genomic islands (GEIs), which vary in size from 3 to 70 kb. Similar work was done by comparing of the genomes of seven clinical isolates of A. baumannii. The analyzed DNAs also showed extensive synteny. We have identified 3068 conserved coding regions in all isolates, and 63 variable genomic loci containing GEIs ranging in size from 4 o 126 kb. GEIs found in A. baumannii and S. maltophilia GEIs are, except for some resistance islands, unrelated.
Additional file 1 of Characterization of runs of homozygosity, heterozygosity-enriched regions, and population structure in cattle populations selected for different breeding goals
Creators: name: Mulim, Henrique Alberto
name: Brito, Luiz F.
name: Pinto, Luís Fernando Batista
name: Ferraz, José Bento Sterman
name: Grigoletto, Lais
name: Silva, Marcio Ribeiro
name: Pedrosa, Victor Breno
Publisher: name: figshare
Year: 2022
Subjects: subject: Genetics
subject: FOS: Biological sciences

description: Additional file 1: Figure S1. Classification of runs of homozygosity according to length size by chromosome in the different breeds.
TECHNOLOGY FOR DEVELOPMENT OF COMMUNICATIVE COMPETENCES OF PRE-SCHOOL CHILDREN
Creators: name: O'ralova, Roziya
Publisher: name: Zenodo
Year: 2024

description: This thesis reflects the study, analysis and development of recommendations for the development of the communicative competence of preschool children, the process of learning the development of the communicative competence of preschool children, the content, form, method, and tools of the technology of developing the communicative competence of preschool children.
Vision based strategies for implementing Sense and Avoid capabilities onboard Unmanned Aerial Systems
Creators: name: Forlenza, Lidia
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2011

description: Current research activities are worked out to develop fully autonomous unmanned platform systems, provided with Sense and Avoid technologies in order to achieve the access to the National Airspace System (NAS), flying with manned airplanes. The TECVOl project is set in this framework, aiming at developing an autonomous prototypal Unmanned Aerial Vehicle which performs Detect Sense and Avoid functionalities, by means of an integrated sensors package, composed by a pulsed radar and four electro-optical cameras, two visible and two Infra-Red. This project is carried out by the Italian Aerospace Research Center in collaboration with the Department of Aerospace Engineering of the University of Naples “Federico II”, which has been involved in the developing of the Obstacle Detection and IDentification system.
Thus, this thesis concerns the image processing technique customized for the Sense and Avoid applications in the TECVOL project, where the EO system has an auxiliary role to radar, which is the main sensor. In particular, the panchromatic camera performs the aiding function of object detection, in order to increase accuracy and data rate performance of radar system. Therefore, the thesis describes the implemented steps to evaluate the most suitable panchromatic camera image processing technique for our applications, the test strategies adopted to study its performance and the analysis conducted to optimize it in terms of false alarms, missed detections and detection range. Finally, results from the tests will be explained, and they will demonstrate that the Electro-Optical sensor is beneficial to the overall Detect Sense and Avoid system; in fact it is able to improve upon it, in terms of object detection and tracking performance.
W.P. Weston, educator and artist : the development of British ideas in the art curriculum of B.C. public schools
Creators: name: Rogers, Anthony William
Publisher: name: University of British Columbia
Year: 2010

description: Using the biographical approach, this thesis examines the transfer of British art education methodology to B.C. schools. Early chapters make a close study of the school art curriculum in Britain and its comprehensive restructuring between 1890 and 1910. Later chapters analyse the transfer of these British ideas to B.C., showing how they eventually formed the basis of the British Columbia art curriculum. As a British immigrant in 1909, William Percy Weston belonged to the dominant ethnic and cultural group then settling in B.C.. With British training and teaching experience, he brought with him the belief, fundamental to British art education, that natural form was the basis of design and beauty. Never abandoning this notion, he spread his ideas well beyond the Provincial Normal School, where he was Art Master from 1914 to 1946. Apart from playing a major role in the art training of teachers he was largely responsible for writing the official provincial art text in 1924 and completely responsible for its 1933 revision. He dominated the 1936 rewriting of elementary and secondary art programmes which became a part of the province's complete overhaul of curricula. Weston also became a prominent artist. Among the first to develop a new vision of the western Canadian landscape, he was an important member of the local artistic community. He finally received national recognition, becoming a charter member of the Canadian Group of Painters in 1933 and the first B.C. Associate of the Royal Canadian Academy in 1936. Throughout the nineteen-thirties he exhibited extensively in national exhibitions and his work was chosen to represent Canada abroad. This thesis shows how British educational ideas were sustained in B.C. by the predominantly British educational establishment long after they were rejected in Britain. Investigating reasons, often unforeseen, for curricular change, the thesis raises important questions about the inadequacy of much curriculum history with its emphasis on official policy and disregard for classroom practice. In elucidating Weston's thought and practice contextually, the thesis points out the conditions which allowed Weston to have such wide influence, contrasting his educational conservatism with his artistic experimentation. Furthermore, it offers an explanation for the way in which school art education policy developed in B.C. and underscores the complex of reasons which encourages, or impedes, change in educational practice. Although ultimately Weston's predominance may have held up educational change in art within the province, he nevertheless brought a coherent and plausible philosophy of art education to B.C. schools, one that served the province well for three or more decades. His enthusiastic and able championing of that philosophy did much to encourage teaching of the subject.
Urbanistica d'occasione. Grandi eventi ed esperienze di rigenerazione urbana della città post-industriale nel Regno Unito
Creators: name: Attademo, Anna
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2011

description: La ricerca affronta il rapporto tra eventi culturali e Grandi Eventi nelle dinamiche di rigenerazione urbana delle aree della città post-moderna e post-industriale. L’evento non è valutato solo in quanto catalizzatore del cambiamento, ma anche e soprattutto in quanto progetto di trasformazione integrata, che costituisca una strategia di condivisione e promozione di immaginari radicati e interconnessi, legati ai significati e alle potenzialità dei territori interessati. In particolar modo, essa esamina, attraverso i casi studio di Liverpool e Londra, l’approccio del modello di pianificazione anglosassone, permeato dei paradigmi moderni di rigenerazione culturale e influenzato dalla gestione strategica delle risorse culturali (cultural planning), come metodo olistico di intervento e modificazione sociale e fisica a partire da pratiche di ripensamento dell’idea di città.
Critical properties of the frustrated Ising model on a honeycomb lattice: A Monte Carlo study
Creators: name: Žukovič, M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Critical and in the highly frustrated regime also dynamical properties of the $J_1-J_2$ Ising model with competing nearest-neighbor $J_1$ and second-nearest-neighbor $J_2$ interactions on a honeycomb lattice are investigated by standard Monte Carlo and parallel tempering simulations. The phase boundary is determined as a function of the coupling ratio for the phase transition between the paramagnetic and ferromagnetic states within $R \equiv J_2/|J_1| \in [-1/4,0]$. It is confirmed that at least for $R \geq -0.2$ the transition remains second-order and complies with the standard Ising universality class. In the highly frustrated regime of $R < -0.2$ and low temperatures the system tends to freeze to metastable domain states, separated by large energy barriers, which show extremely sluggish dynamics. The resulting huge equilibration and autocorrelation times hinder the analysis of critical properties and thus the character of the transition in this region remains to be determined.
description: 10 pages, 4 figures
Nuove metodologie di studio dell'anatomia del sistema nervoso centrale in cadavere mediante tecniche di neuroimmagine, modelli computazionali e ricostruzioni tridimensionali. Sviluppo e future applicazioni per i principali approcci neurochirurgici
Creators: name: De Notaris, Matteo
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2011

description: The goal of the present study was to develop a computer based three-dimensional (3D) anatomical and geometrical model of neurosurgical approaches. Such model can be employed for teaching surgical anatomy, developing surgical guidelines and provide for an advanced preoperative rehearsal system where surgeons try surgical procedure on a Computed Tomography (CT-scan) and Magnetic Resonance Imaging (MRI)-based imaging system.
Additional file 2 of Characterization of runs of homozygosity, heterozygosity-enriched regions, and population structure in cattle populations selected for different breeding goals
Creators: name: Mulim, Henrique Alberto
name: Brito, Luiz F.
name: Pinto, Luís Fernando Batista
name: Ferraz, José Bento Sterman
name: Grigoletto, Lais
name: Silva, Marcio Ribeiro
name: Pedrosa, Victor Breno
Publisher: name: figshare
Year: 2022
Subjects: subject: Genetics
subject: FOS: Biological sciences

description: Additional file 2: Figure S2. Classification of heterozygous-enriched regions according to length size by chromosome in the different breeds.
Risposta adattativa del sistema Posidonia
alla variabilità ambientale
Creators: name: Silvestre, Filippo
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2013

description: Le recenti politiche ambientali europee (WFD 2000/60/CE e la Marine Strategy 2008/56/CE) hanno imposto la classificazione ed il raggiungimento del buono stato ecologico delle acque costiere degli Stati europei. Al fine della classificazione dei corpi idrici, le Direttive europee considerano diversi elementi biologici di qualità, tra cui il sistema Posidonia oceanica. Nella presente tesi di dottorato è stato realizzato un sistema di  classificazione dello stato ecologico, basato su diverse metriche relative a Posidonia oceanica (densità della prateria, produzione del rizoma, allungamento annuale del rizoma e produzione fogliare). I dati utilizzati per il metodo di classificazione sono stati organizzati con tecniche di Data Base Management System. In tal modo il sistema può essere continuamente implementato da dati di
diversi programmi di monitoraggio e potrà essere usufruibile da chiunque abbia necessità di classificare lo stato ecologico di un corpo d’acqua costiero. Il metodo di classificazione è stato validato utilizzando dati provenienti da passati programmi di monitoraggio
regionale ed è stato poi confrontato con diversi indici di pressione antropica sviluppati da alcune regioni.
Measurements of the observed cross sections for $e^+e^- \to$ light hadrons at $\sqrt{s}=$ 3.773 and 3.650 GeV
Creators: name: BES Collaboration
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Using the data sets of 17.3 pb$^{-1}$ collected at $\sqrt{s}=$ 3.773 GeV and 6.5 pb$^{-1}$ collected at $\sqrt{s}=$ 3.650 GeV with the BESII detector at the BEPC collider, we have measured the observed cross sections for 18 exclusive light hadron final states produced in $e^+e^-$ annihilation at the two energy points.
description: 9 pages, 5 figures