cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Mapped Null Hypersurfaces and Legendrian Maps
Creators: name: Chernov, Vladimir
Publisher: name: arXiv
Year: 2007
Subjects: subject: Differential Geometry (math.DG)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Geometric Topology (math.GT)
subject: Symplectic Geometry (math.SG)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: Primary 53C50; Secondary 57R17

description: For an $(m+1)$-dimensional space-time $(X^{m+1}, g),$ define a mapped null hypersurface to be a smooth map $ν:N^{m}\to X^{m+1}$ (that is not necessarily an immersion) such that there exists a smooth field of null lines along $ν$ that are both tangent and $g$-orthogonal to $ν.$ We study relations between mapped null hypersurfaces and Legendrian maps to the spherical cotangent bundle $ST^*M$ of an immersed spacelike hypersurface $μ:M^m\to X^{m+1}.$ We show that a Legendrian map $\wt λ: L^{m-1}\to (ST^*M)^{2m-1}$ defines a mapped null hypersurface in $X.$ On the other hand, the intersection of a mapped null hypersurface $ν:N^m\to X^{m+1}$ with an immersed spacelike hypersurface $μ':M'^m\to X^{m+1}$ defines a Legendrian map to the spherical cotangent bundle $ST^*M'.$ This map is a Legendrian immersion if $ν$ came from a Legendrian immersion to $ST^*M$ for some immersed spacelike hypersurface $μ:M^m\to X^{m+1}.$
description: 13 pages, 1 figure
Self-assembly of active amphiphilic Janus particles
Creators: name: Mallory, S. A.
name: Alarcon, F.
name: Cacciuto, A.
name: Valeriani, C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: In this article, we study the phenomenology of a two dimensional dilute suspension of active amphiphilic Janus particles. We analyze how the morphology of the aggregates emerging from their self-assembly depends on the strength and the direction of the active forces. We systematically explore and contrast the phenomenologies resulting from particles with a range of attractive patch coverages. Finally, we illustrate how the geometry of the colloids and the directionality of their interactions can be used to control the physical properties of the assembled active aggregates and suggest possible strategies to exploit self-propulsion as a tunable driving force for self-assembly.
S1 R_code. R script for Improving the diagnostic recognition of thoracic endometriosis: Spotlight on a new histo-morphological indicator.
Creators: name: Okechukwu Okafor
name: Ndubueze Ezemba
name: Nnaemeka Onyishi
name: Ezike, Kevin
Publisher: name: figshare
Year: 2021
Subjects: subject: Pathology
subject: 110323 Surgery
subject: FOS: Clinical medicine
subject: 80301 Bioinformatics Software
subject: FOS: Computer and information sciences
subject: 60102 Bioinformatics

description: R script for the analysis of the histopathological features of thoracic endometriosis (TE) using ggplot2, DT, pROC and vcd packages in R statistical software. The aim is to review the histopathological findings in TE, summarise the diagnostic features, identify any major histo-morphological indicator(s) hitherto unrecognised as such, suggest diagnostic algorithms; all with the aim of improving the diagnostic capacity and reducing observer error even where the clinical suspicion is low. Statistical methods applied include chi-squared test of independence, Cramér’s V test of strength of association and the area under the curve of the receiver operating characteristic (AUC-ROC) curve. The final conclusion is summarised with a Venn plot identifying endometrioid glands, ceroid macrophages, siderophages and lymphoid clusters as the major markers of TE.
Bond-space operator disentangles quasi-localized and phononic modes in structural glasses
Creators: name: Giannini, Julia A
name: Richard, David
name: Manning, M. Lisa
name: Lerner, Edan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: The origin of several emergent mechanical and dynamical properties of structural glasses is often attributed to populations of localized structural instabilities, coined quasilocalized modes (QLMs). Under a restricted set of circumstances, glassy QLMs can be revealed by analyzing computer glasses' vibrational spectra in the harmonic approximation. However, this analysis has limitations due to system-size effects and hybridization processes with low energy phononic excitations (plane waves) that are omnipresent in elastic solids. Here we overcome these limitations by exploring the spectrum of a linear operator defined on the space of particle interactions (bonds) in a disordered material. We find that this bond-force-response operator offers a unique interpretation of QLMs in glasses, and cleanly recovers some of their important statistical and structural features. The analysis presented here reveals the dependence of the number density (per frequency) and spatial extent of QLMs on material preparation protocol (annealing). Finally, we discuss future research directions and possible extensions of this work.
Transmutation of momentum into position in magnetic vortices
Creators: name: Komineas, Stavros
name: Papanicolaou, Nikos
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We show that transmutation of linear momentum into position may occur in a system of three magnetic vortices thanks to a direct link between topology and dynamics in a ferromagnet. This happens via exchange between the linear momentum of a vortex-antivortex pair and the position of a single vortex during a semi-elastic scattering process. Vortex polarity switching occurs in the case of inelastic collisions.
description: 9 pages, 6 figures
Genetic effects on wood shrinkage, relative density, grain angle, tracheid length, and fibril angle in Douglas-fir (Pseudotsuga menziessi var. menziesii (mirb.) franco)
Creators: name: Koshy, Mathew P.
Publisher: name: University of British Columbia
Year: 2012

description: Seven wood traits: shrinkage (longitudinal, tangential, and radial), relative density, grain angle, tracheid length, and fibril angle, and two growth traits, height and diameter at breast height were analyzed in 413 trees belonging to 48 full-sibfamilies (4 pollen and 12 seed parents) from an 18- year-old coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) progeny test . Clones from six of the parents also were sampled. Six samples per age level (age levels 0 to 4 along stem radii), with two rings in each age level, were examined in a bolt taken at breast height of the tree for shrinkage and relative density. Smaller sample sizes were used for the other traits. Trends with age from the pith were decreasing longitudinal shrinkage and fibril angle and increasing radial and tangential shrinkage, grain angle, and tracheid length. Relative density first decreased and then increased beyond age level 2. Genetic effects were minimal for wood quality traits except for relative density. Most of the variation for wood quality traits was within tree and between individual trees within families. Genetic correlations between wood quality traits were minimal except between relative density and radial shrinkage, which was positive. Genetic correlations between growth characters like height and diameter at breast height and wood quality traits were also minimal except for relative density and longitudinal shrinkage at early age levels. Selection for increased height can be expected to reduce longitudinal shrinkage and relative density at early age levels, and have virtually no effect on the other traits studied. The results support current efforts to increase wood production through genetic improvement in growth rate by showing that current programs of selection for rapid early height growth will not (with the exception of relative density) result in substantial reductions in several wood quality traits beyond the first few years of tree growth. The demonstrated lack of substantial genetic effects for several traits indicated that genetic improvement can progress more rapidly by concentrating on a much smaller number of traits.
Kerr black hole lensing for generic observers in the strong deflection limit
Creators: name: Bozza, V.
name: De Luca, F.
name: Scarpetta, G.
Publisher: name: arXiv
Year: 2006
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We generalize our previous work on gravitational lensing by a Kerr black hole in the strong deflection limit, removing the restriction to observers on the equatorial plane. Starting from the Schwarzschild solution and adding corrections up to the second order in the black hole spin, we perform a complete analytical study of the lens equation for relativistic images created by photons passing very close to a Kerr black hole. We find out that, to the lowest order, all observables (including shape and shift of the black hole shadow, caustic drift and size, images position and magnification) depend on the projection of the spin on a plane orthogonal to the line of sight. In order to break the degeneracy between the black hole spin and its inclination relative to the observer, it is necessary to push the expansion to higher orders. In terms of future VLBI observations, this implies that very accurate measures are needed to determine these two parameters separately.
description: 17 pages, 4 figures, one section added, to appear on Physical Review D
Can a vector field be responsible for the curvature perturbation in the Universe?
Creators: name: Dimopoulos, Konstantinos
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Astrophysics (astro-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: I investigate the possibility that the observed curvature perturbation is due to a massive vector field. To avoid generating a large scale anisotropy the vector field is not taken to be driving inflation. Instead it is assumed to become important after inflation when it may dominate the Universe and imprint its perturbation spectrum before its decay, as in the curvaton scenario. It is found that, to generate a scale invariant spectrum of perturbations, the mass-squared of the vector field has to be negative and comparable to the Hubble scale during inflation. After inflation the mass-squared must become positive so that the vector field engages into oscillations. It is shown that, such an oscillating vector field behaves as pressureless matter and does not lead to large scale anisotropy when it dominates the Universe. The possibilitiy of realising this scenario in supergravity is also outlined.
description: 9 pages 1 figure, revtex. Added figure. Version published in PRD
Energetics of collapsible channel flow with a nonlinear fluid-beam model
Creators: name: Wang, Danyang
name: Luo, Xiaoyu
name: Stewart, Peter
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We consider flow along a finite-length collapsible channel driven by a fixed upstream flux, where a section of one wall of a planar rigid channel is replaced by a plane-strain elastic beam subject to uniform external pressure. A modified constitutive law is used to ensure that the elastic beam is energetically conservative. We apply the finite element method to solve the fully nonlinear steady and unsteady systems. In line with previous studies, we show that the system always has at least one static solution and that there is a narrow region of the parameter space where the system simultaneously exhibits two stable static configurations: an (inflated) upper branch and a (collapsed) lower branch, connected by a pair of limit point bifurcations to an unstable intermediate branch. Both upper and lower static configurations can each become unstable to self-excited oscillations, initiating either side of the region with multiple static states. As the Reynolds number increases along the upper branch the oscillatory limit cycle persists into the region with multiple steady states, where interaction with the intermediate static branch suggests a nearby homoclinic orbit. These oscillations approach zero amplitude at the upper branch limit point, resulting in a stable tongue between the upper and lower branch oscillations. Furthermore, this new formulation allows us to calculate a detailed energy budget over a period of oscillation, where we show that both upper and lower branch instabilities require an increase in the work done by the upstream pressure to overcome the increased dissipation.
description: 27 pages, 10 figures, under review
Integrability of Type II Superstrings on Ramond-Ramond Backgrounds in Various Dimensions
Creators: name: Adam, Ido
name: Dekel, Amit
name: Mazzucato, Luca
name: Oz, Yaron
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider type II superstrings on AdS backgrounds with Ramond-Ramond flux in various dimensions. We realize the backgrounds as supercosets and analyze explicitly two classes of models: non-critical superstrings on AdS_{2d} and critical superstrings on AdS_p\times S^p\times CY. We work both in the Green--Schwarz and in the pure spinor formalisms. We construct a one-parameter family of flat currents (a Lax connection) leading to an infinite number of conserved non-local charges, which imply the classical integrability of both sigma-models. In the pure spinor formulation, we use the BRST symmetry to prove the quantum integrability of the sigma-model. We discuss how classical κ-symmetry implies one-loop conformal invariance. We consider the addition of space-filling D-branes to the pure spinor formalism.
description: LaTeX2e, 56 pages, 1 figure, JHEP style; v2: references added, typos fixed in some equations; v3: typos fixed to match the published version
title: Lusitania Sacra, No 38 (2018)
title: Goa: missionação, política e territorialidade no contexto pós-tridentino
titleType: AlternativeTitle
Creators: name: Lusitania Sacra
Publisher: name: Lusitania Sacra
Year: 2021

description: Apresentação...9-13 Política ou missionação? Alessandro Valignano e as controvérsias da primeira visitação da Índia (1573-1580)...17-47 O Primeiro Concílio de Goa e a releitura da escravidão na Ásia (1567)...49-78 Um franco atirador numa guerra de cem anos: o padre Pedro Borges e a questão das paróquias na Goa da Contra-Reforma...79-154 A Reforma e a Religiosidade Feminina em Goa entre 1721 e 1739...155-179 A graça e a desgraça das relíquias do Judaísmo. O sermão de D. Frei Diogo da Anunciação Justiniano, arcebispo de Cranganor e as suas respostas: circulação e reapropriação...183-204 A Confessio Augustana e o Catecismo de Heidelberg como instrumentos do processo da confessionalização...205-227 A Ordem Terceira do Carmo de Pombal na Época Moderna: governação e formas de crédito...229-244 A propósito de possíveis relações culturais entre Pedro Hispano e Afonso X de Castela...245-259 I Simpósio sobre o Judaísmo em Trás-os-Montes...263-264 Colóquio «Ornaverunt Lampades. A arte Cristã na Herança de Luiza Andaluz»...264-265 Ciência Vitae: Apresentação às unidades de I&D da nova plataforma de gestão curricular...265-268 Iniciativas científicas e culturais no âmbito da história religiosa (2018)...269-306 Relatório de atividades do CEHR (2018)...307-321 KNAUF, Ernst Axel; GUILLAUME, Philippe – A History of Biblical Israel. The Fate of the Tribes and Kingdoms from Merenptah to Bar Kochba...325-326 ALVES, Herculano – A Bíblia em Portugal. Vol. I: As línguas da Bíblia: 23 séculos de traduções...326-330 J. HERNÁNDEZ, Francisco; SÁNCHEZ AMEIJEIRAS; Rocío; FALQUE, Emma (eds) – Medieval studies in honour of Peter Linehan...330-332 CARREIRAS, José Albuquerque; VAIRO, Giulia Rossi; TOOMASPOEG, Kristjan (eds) – Através do olhar do Outro. Reflexões acerca da sociedade medieval europeia (séculos XII-XIV)...332-337 FERNANDES, Isabel Cristina (coord.) – Entre Deus e o Rei. O mundo das Ordens Militares...338-339 GIEBELS, Daniel Norte – A Inquisição de Lisboa (1537-1579)...340-342 MÜHLING, Christian – Die europäische Debatte über den Religionskrieg (1679-1714)...342-345 FRANCO, José Eduardo; REIS, Bruno Cardoso – Fátima: lugar sagrado global...349-350 FERREIRA, Pe. Manuel Augusto Lopes – Missionários Combonianos em Portugal: uma história singular...350-352 FRANCO, José Eduardo; PEREIRA, José Carlos Seabra (dir.) – Portugal Católico: a beleza na diversidade...352-354
Chiral scattering in complex magnets
Creators: name: Maleyev, S. V.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: General properties of the chiral scattering of polarized neutrons are considered for two possible axial vector interactions: Zeeman energy and non-alternating Dzyaloshinskii-Moriya interaction. Behavior in magnetic field of helical magnetic structures is discussed for $Mn Si$ and magneto-electric materials. The dynamical chiral fluctuations in magnetic field are considered briefly. The chiral fluctuations in materials with the Dzyaloshinskii-Moriya interaction are discussed and an assumption is made that above the transition temperature they have to be incommensurate.
description: 8 p
A fully-kinetic model for orphan gamma-ray flares in blazars
Creators: name: Sobacchi, Emanuele
name: Nättilä, Joonas
name: Sironi, Lorenzo
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Blazars emit a highly-variable non-thermal spectrum. It is usually assumed that the same non-thermal electrons are responsible for the IR-optical-UV emission (via synchrotron) and the gamma-ray emission (via inverse Compton). Hence, the light curves in the two bands should be correlated. Orphan gamma-ray flares (i.e., lacking a luminous low-frequency counterpart) challenge our theoretical understanding of blazars. By means of large-scale two-dimensional radiative particle-in-cell simulations, we show that orphan gamma-ray flares may be a self-consistent by-product of particle energization in turbulent magnetically-dominated pair plasmas. The energized particles produce the gamma-ray flare by inverse Compton scattering an external radiation field, while the synchrotron luminosity is heavily suppressed since the particles are accelerated nearly along the direction of the local magnetic field. The ratio of inverse Compton to synchrotron luminosity is sensitive to the initial strength of turbulent fluctuations (a larger degree of turbulent fluctuations weakens the anisotropy of the energized particles, thus increasing the synchrotron luminosity). Our results show that the anisotropy of the non-thermal particle population is key to modeling the blazar emission.
description: accepted for publication in MNRAS
TEM10 homodyne detection as an optimal small displacement and tilt measurements scheme
Creators: name: Delaubert, Vincent
name: Treps, Nicolas
name: Lassen, Mikael
name: Harb, Charles C.
name: Fabre, Claude
name: Lam, Ping Koy
name: Bachor, Hans A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We report an experimental demonstration of optimal measurements of small displacement and tilt of a Gaussian beam - two conjugate variables - involving a homodyne detection with a TEM10 local oscillator. We verify that the standard split detection is only 64% efficient. We also show a displacement measurement beyond the quantum noise limit, using a squeezed vacuum TEM10 mode within the input beam.
description: 9 pages, 8 figures
Zur Erinnerung an Dr. iur. Ernst Kaegi-Winter, geb. in Zürich am 20. Juli 1888, gest. in Basel am 9. Nov. 1918
Creators: name: (:Unkn) Unknown
Publisher: name: Druckerei der National-Zeitung
Year: 1918
Subjects: subject: 920 Biografien, Genealogie, Insignien
subject: Nachruf
subject: Kaegi-Winter, Ernst

description: Enthält: Lebenslauf von Freundeshand gezeichnet; Ansprache gehalten am 12. November 1918 auf dem Wolf-Gottesacker von A. v. Salis, Pfarrer am Münster.
On Lorentz geometry in algebras of generalized functions
Creators: name: Mayerhofer, Eberhard
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mathematical Physics (math-ph)
subject: Rings and Algebras (math.RA)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 46F30, 46T30, 46F10, 83C05

description: We introduce a concept of causality in the framework of generalized pseudo-Riemannian Geometry in the sense of J.F. Colombeau and establish the inverse Cauchy-Schwarz inequality in this context. As an application, we prove a dominant energy condition for some energy tensors as put forward in Hawking and Ellis's book "The large scale structure of space-time". Our work is based on a new characterization of free elements in finite dimensional modules over the ring of generalized numbers.
description: 26 pages, reorganized, updated references
N-representability is QMA-complete
Creators: name: Liu, Y. -K.
name: Christandl, M.
name: Verstraete, F.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study the computational complexity of the N-representability problem in quantum chemistry. We show that this problem is QMA-complete, which is the quantum generalization of NP-complete. Our proof uses a simple mapping from spin systems to fermionic systems, as well as a convex optimization technique that reduces the problem of finding ground states to N-representability.
Knowledge Gaps in the Cometary Spectra of Oxygen-Bearing Molecular Cations
Creators: name: Fortenberry, Ryan
name: Bodewits, Dennis
name: Pierce, Donna
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Molecular cations are present in various astronomical environments, most notably in cometary atmospheres and tails where sunlight produces exceptionally bright near-UV to visible transitions. Such cations typically have longer-wavelength and brighter electronic emission than their corresponding neutrals. A robust understanding of their near-UV to visible properties would allow these cations to be used as tools for probing the local plasma environments or as tracers of neutral gas in cometary environments. However, full spectral models are not possible for characterization of small, oxygen containing molecular cations given the body of molecular data currently available. The five simplest such species (H2O+, CO+2 , CO+, OH+, and O+2 ) are well characterized in some spectral regions but are lacking robust reference data in others. Such knowledge gaps hinder fully quantitative models of cometary spectra, specifically, hindering accurate estimates of physical-chemical processes originating with the most common molecules in comets. Herein the existing spectral data are collected for these molecules and highlight the places where future work is needed, specifically where the lack of such data would greatly enhance the understanding of cometary evolution.
description: Accepted by APJS
Shock-Wave Heating Model for Chondrule Formation: Hydrodynamic Simulation of Molten Droplets exposed to Gas Flows
Creators: name: Miura, Hitoshi
name: Nakamoto, Taishi
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Millimeter-sized, spherical silicate grains abundant in chondritic meteorites, which are called as chondrules, are considered to be a strong evidence of the melting event of the dust particles in the protoplanetary disk. One of the most plausible scenarios is that the chondrule precursor dust particles are heated and melt in the high-velocity gas flow (shock-wave heating model). We developed the non-linear, time-dependent, and three-dimensional hydrodynamic simulation code for analyzing the dynamics of molten droplets exposed to the gas flow. We confirmed that our simulation results showed a good agreement in a linear regime with the linear solution analytically derived by Sekiya et al. (2003). We found that the non-linear terms in the hydrodynamical equations neglected by Sekiya et al. (2003) can cause the cavitation by producing negative pressure in the droplets. We discussed that the fragmentation through the cavitation is a new mechanism to determine the upper limit of chondrule sizes. We also succeeded to reproduce the fragmentation of droplets when the gas ram pressure is stronger than the effect of the surface tension. Finally, we compared the deformation of droplets in the shock-wave heating with the measured data of chondrules and suggested the importance of other effects to deform droplets, for example, the rotation of droplets. We believe that our new code is a very powerful tool to investigate the hydrodynamics of molten droplets in the framework of the shock-wave heating model and has many potentials to be applied to various problems.
description: Accepted in Icarus, 50 Pages, 1 Table, and 13 Figures
Neutrinos, Axions and Conformal Symmetry
Creators: name: Meissner, Krzysztof A.
name: Nicolai, Hermann
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We demonstrate that radiative breaking of conformal symmetry (and simultaneously electroweak symmetry) in the Standard Model with right-chiral neutrinos and a minimally enlarged scalar sector induces spontaneous breaking of lepton number symmetry, which naturally gives rise to an axion-like particle with some unusual features. The couplings of this `axion' to Standard Model particles, in particular photons and gluons, are entirely determined (and computable) via the conformal anomaly, and their smallness turns out to be directly related to the smallness of the masses of light neutrinos.
description: 10 pages, 2 figures, expanded version, to be published in EPJ C
Instabilities in the nonsymmetric theory of gravitation
Creators: name: Janssen, Tomas
name: Prokopec, Tomislav
Publisher: name: arXiv
Year: 2006
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We consider the linearized nonsymmetric theory of gravitation (NGT) within the background of an expanding universe and near a Schwarzschild metric. We show that the theory always develops instabilities unless the linearized nonsymmetric lagrangian reduces to a particular simple form. This theory contains a gauge invariant kinetic term, a mass term for the antisymmetric metric-field and a coupling with the Ricci curvature scalar. This form cannot be obtained within NGT. Next we discuss NGT beyond linearized level and conjecture that the instabilities are not a relic of the linearization, but are a general feature of the full theory. Finally we show that one cannot add ad-hoc constraints to remove the instabilities as is possible with the instabilities found in NGT by Clayton.
description: 29 pages
A Unifying Modeling Abstraction for Infinite-Dimensional Optimization
Creators: name: Pulsipher, Joshua L.
name: Zhang, Weiqi
name: Hongisto, Tyler J.
name: Zavala, Victor M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optimization and Control (math.OC)
subject: Systems and Control (eess.SY)
subject: FOS: Mathematics
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Infinite-dimensional optimization (InfiniteOpt) problems involve modeling components (variables, objectives, and constraints) that are functions defined over infinite-dimensional domains. Examples include continuous-time dynamic optimization (time is an infinite domain and components are a function of time), PDE optimization problems (space and time are infinite domains and components are a function of space-time), as well as stochastic and semi-infinite optimization (random space is an infinite domain and components are a function of such random space). InfiniteOpt problems also arise from combinations of these problem classes (e.g., stochastic PDE optimization). Given the infinite-dimensional nature of objectives and constraints, one often needs to define appropriate quantities (measures) to properly pose the problem. Moreover, InfiniteOpt problems often need to be transformed into a finite dimensional representation so that they can be solved numerically. In this work, we present a unifying abstraction that facilitates the modeling, analysis, and solution of InfiniteOpt problems. The proposed abstraction enables a general treatment of infinite-dimensional domains and provides a measure-centric paradigm to handle associated variables, objectives, and constraints. This abstraction allows us to transfer techniques across disciplines and with this identify new, interesting, and useful modeling paradigms (e.g., event constraints and risk measures defined over time domains). Our abstraction serves as the backbone of an intuitive Julia-based modeling package that we call InfiniteOpt.jl. We demonstrate the developments using diverse case studies arising in engineering.
On the number of linear forms in logarithms
Creators: name: Lamzouri, Youness
Publisher: name: arXiv
Year: 2006
Subjects: subject: Number Theory (math.NT)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 11N25, 05A05

description: Let $n$ be a positive integer. In this paper we estimate the size of the set of linear forms $b_1\log a_1 + b_2\log a_2+...+b_n\log a_n$, where $|b_i|\leq B_i$ and $1\leq a_i\leq A_i$ are integers, as $A_i,B_i\to \infty$.
description: 8 pages
title: Handling of a disbalanced stick tool in the Goffin's cockatoo
Creators: name: Nasa, Özge
Year: 2024

description: Papageien (Psittaciformes) verfügen über einzigartige morphologische und verhaltensbiologische Merkmale, welche einen flexiblen und effizienten Werkzeuggebrauch, insbesondere mit Stöcken, ermöglichen, vergleichbar mit dem der Primaten. Bei werkzeugbenutzenden Arten kann die Beachtung gewichtsbezogener Hinweise die Effizienz der Nahrungssuche erhöhen, indem die energetischen Kosten der Werkzeugmanipulation minimiert werden. Frühere Forschungen haben gezeigt, dass Goffin-Kakadus (Cacatua goffiniana) gewichtsbezogene Hinweise erkennen und nutzen können, aber ihre Empfindlichkeit gegenüber unausgewogenen Objekten in funktionalen Werkzeugkontexten blieb bisher unerforscht. In dieser Studie wurde untersucht, wie Goffin-Kakadus mit einem unbalancierten Stockwerkzeug umgehen und welche individuellen Techniken sie anwenden, um ein bekanntes Stock-Werkzeug-Kasten-Problem zu lösen. Wir führten eine Reihe von Experimenten mit demselben allgemeinen Aufbau, aber unterschiedlichen Freiheitsgraden durch und untersuchten Veränderungen bei den Insertionstechniken und die Präferenzen der Handhabung des Stocks mit dem schwereren Ende im Schnabel - eine Strategie, welche die energetischen Kosten reduziert. Unsere Ergebnisse zeigten, dass Goffin-Kakadus auf Gruppenebene den Stock lieber so handhaben, dass der Schwerpunkt näher an der Greifstelle liegt. Darüber hinaus zeigten die Vögel hochgradig individualisierte Anpassungen der Technik, um neue Probleme zu lösen. Wir vermuten, dass Vögel, die ihre Techniken in dieser Situation nicht adaptierten, in der Lage sein könnten, dies unter erhöhten Einschränkungen der Lösungsmöglichkeiten zu tun. Diese Ergebnisse liefern den ersten Beweis dafür, dass Goffin-Kakadus auf eine unbalancierte Gewichtsverteilung in einem funktionalen Werkzeug achten und sich daran anpassen, was ihre Flexibilität bei der Problemlösung und ihre Sensibilität für physikalische Werkzeugeigenschaften unterstreicht.
CARREIRAS, José Albuquerque; VAIRO, Giulia Rossi; TOOMASPOEG, Kristjan (eds) – Através do olhar do Outro. Reflexões acerca da sociedade medieval europeia (séculos XII-XIV)
Creators: name: Renzi, Francesco
Publisher: name: Lusitania Sacra
Year: 2021

description: Lusitania Sacra, No 38 (2018)
Efficient Realistic Data Generation Framework leveraging Deep Learning-based Human Digitization
Creators: name: Symeonidis, C.
name: Nousi, P.
name: Tosidis, P.
name: Tsampazis, K.
name: Passalis, N.
name: Tefas, A.
name: Nikolaidis, N.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: The performance of supervised deep learning algorithms depends significantly on the scale, quality and diversity of the data used for their training. Collecting and manually annotating large amount of data can be both time-consuming and costly tasks to perform. In the case of tasks related to visual human-centric perception, the collection and distribution of such data may also face restrictions due to legislation regarding privacy. In addition, the design and testing of complex systems, e.g., robots, which often employ deep learning-based perception models, may face severe difficulties as even state-of-the-art methods trained on real and large-scale datasets cannot always perform adequately due to not having been adapted to the visual differences between the virtual and the real world data. As an attempt to tackle and mitigate the effect of these issues, we present a method that automatically generates realistic synthetic data with annotations for a) person detection, b) face recognition, and c) human pose estimation. The proposed method takes as input real background images and populates them with human figures in various poses. Instead of using hand-made 3D human models, we propose the use of models generated through deep learning methods, further reducing the dataset creation costs, while maintaining a high level of realism. In addition, we provide open-source and easy to use tools that implement the proposed pipeline, allowing for generating highly-realistic synthetic datasets for a variety of tasks. A benchmarking and evaluation in the corresponding tasks shows that synthetic data can be effectively used as a supplement to real data.
Characterisation of a novel pathway for ribosomal RNA maturation in Sulfolobus acidocaldarius
Creators: name: Durovic, Peter Vincent
Publisher: name: University of British Columbia
Year: 2012

description: Since the initial proposition that the archaebacteria form a primary kingdom as distinct as that of the eubacteria or the eukaryotes, sequence data generated from the ribosomal RNA genes have flooded the databases and periodicals. Phylogenetic trees based on these sequences have been constructed to map the finest details of topology and branching order within the archaebacteria. Yet, despite the plethora of sequence data, relatively little was discovered regarding rRNAgene regulation, transcript processing and requirements for mature ribosome function. The aim of this study is to analyze possible novel regulatory mechanisms in the rRNA genes of the extremely thermoacidophilic archaebacterium Sulfolobus acidoccddccrius. The three ribosomal RNA genes were cloned and sequenced. The gene organization was confirmed to differ from that of the halophilic archaebacteria and the eubacteria: the 5S gene was not linked to the 16S and 23S operon, and the operon lacked recognizable tRNA sequences. Southern hybridization unveiled, and sequence data confirmed a long-standing confusion regarding species identity. The previously published Sulfolobus acidocaldarius 5S sequence was shown to have been attributed to the wrong species. Mapping experiments showed that both transcripts initiated downstream of a previously defined archaebacteria! promoter sequence. While sequence data showed the 5S transcript start site and end site to be coincidental with the mature 5S termini, the 16S-23S transcript was shown to contain a 143 nucleotide transcribed leader sequence, a 138 nucleotide intergenic sequence, and a trailer sequence of at least 105 nucleotides. Inverted repeat sequences within these transcribed non-coding regions allow for the formation of numerous stem-loops conforming to a semi-conserved archaebacterial structure. While no processing took place within the 5S transcript, extensive processing of the 16S-23S transcript was observed. Of the 12 processing sites mapped, only 6 could be accounted for in the context of precursor processing and maturation events known directly or inferred by analogy from the halophilic archaebacteria and the eubacteria. Alignment of the remaining sites revealed a non-trivial sequence and structural similarity. If the novel processing indeed took place in the postulated context, it would mark a radical departure from the expected maturation mechanism thought to predate the speciation of archaebacteria and eubacteria. To examine this possibility, in vitro transcripts from judiciously selected DNA fragments were subjected to cell-free extract. Analysis of the resultant cleavage products confirmed the presence not only of a novel processing activity mediated by a ribonucleoprotein complex but also of a novel processing pathway. Based on the locations of the novel processing sites within the primary 16S-23S transcript, a model for transcriptional regulation independent of polycistronic linkage is presented.
Effects of site preparation in interior plateau clearcuts on the soil water regime and the water relations of conifer seedlings
Creators: name: Fleming, Robert LeSueur
Publisher: name: University of British Columbia
Year: 2012

description: Site preparation effects on growing season soil water regimes were investigated on three clearcut, grass-dominated sites in the Interior Douglas-fir (IDFdk), Montane Spruce (MSxk) and Engelmann spruce-Subalpine fir (ESSFxc) Biogeoclimatic Subzones, near Kamloops, British Columbia. The response of newly planted Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and lodgepole pine (Pinus contorta Dougl.) to these treatments was determined at the IDFdk site. Soil water regimes were measured in scalped, ripped and herbicide site preparation treatments and in an untreated control using a neutron moisture meter, a two-probe gamma-density gauge, tensiometers and thermocouple psychrometers. At the IDFdk, seedlings were spring planted in each of the treatments and control to determine whether microclimate modification by site preparation would improve seedling water relations, growth and survival during the first growing season. Root zone soil water content was most limited at the low-elevation site (IDFdk) and least limited at the high-elevation site (ESSFxc). The different site preparation treatments provided similar increases in root zone soil water content, profile water storage and drainage at each site. This resulted in substantial increases in soil water supply at the lowest two sites. Site preparation resulted in increased Douglas-fir and lodgepole pine stomatal conductance (gs), transpiration (E), leaf area, root egress, root collar basal area and dry matter production. Survival of both species was high in the control and in all site preparation treatments. Both species had similar seasonal patterns of gs and E in the control. In the site preparation treatments, lodgepole pine had greater gs, and by late summer, greater E than Douglas-fir. Although lodgepole pine had substantially higher twig xylem pressure potentials and lower soil-plant liquid flow resistances than Douglas-fir, both species appeared well adapted to survive drought. First growing season stomatal responses of both species to environmental conditions, including normalized vapor pressure deficit at seedling height (Ds/P), solar irradiance (Rs) and root zone extractable water (Φe), were similar when normalized against annual maximum conductance (gsmax ). A multiplicative model with non-linear least squares optimization (NLLS) of response functions to Rs, Ds/P and Φe provided a simple, reasonably accurate description of gs/gsmax for both species, and accounted for differences in gs between the control and ripped treatment. In most cases, the NLLS models developed for a given species and year resulted in relatively precise (R²>0.60) and unbiased estimates of gs /gsmax, and yielded estimates of mean daily stomatal conductance (Gs ) and total daily transpiration (T) within 20% of measured values, for the same species in other years.
Strong interminivalley scattering in twisted bilayer graphene revealed by high-temperature magnetooscillations
Creators: name: Phinney, I. Y.
name: Bandurin, D. A.
name: Collignon, C.
name: Dmitriev, I. A.
name: Taniguchi, T.
name: Watanabe, K.
name: Jarillo-Herrero, P.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Twisted bilayer graphene (TBG) provides an example of a system in which the interplay of interlayer interactions and superlattice structure impacts electron transport in a variety of non-trivial ways and gives rise to a plethora of interesting effects. Understanding the mechanisms of electron scattering in TBG has, however, proven challenging, raising many questions about the origins of resistivity in this system. Here we show that TBG exhibits high-temperature magnetooscillations originating from the scattering of charge carriers between TBG minivalleys. The amplitude of these oscillations reveals that interminivalley scattering is strong, and its characteristic time scale is comparable to that of its intraminivalley counterpart. Furthermore, by exploring the temperature dependence of these oscillations, we estimate the electron-electron collision rate in TBG and find that it exceeds that of monolayer graphene. Our study demonstrates the consequences of the relatively small size of the superlattice Brillouin zone and Fermi velocity reduction on lateral transport in TBG.
description: 10 pages, 6 figures
The evolution of compressible solar wind turbulence in the inner heliosphere: PSP, THEMIS and MAVEN observations
Creators: name: Andrés, N.
name: Sahraoui, F.
name: Hadid, L. Z.
name: Huang, S. Y.
name: Romanelli, N.
name: Galtier, S.
name: DiBraccio, G.
name: Halekas, J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Space Physics (physics.space-ph)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: The first computation of the compressible energy transfer rate from $\sim$ 0.2 AU up to $\sim$ 1.7 AU is obtained using PSP, THEMIS and MAVEN observations. The compressible energy cascade rate $\varepsilon_C$ is computed for hundred of events at different heliocentric distances, for time intervals when the spacecraft were in the pristine solar wind. The observational results show moderate increases of $\varepsilon_C$ with respect to the incompressible cascade rate $\varepsilon_I$. Depending on the level of compressibility in the plasma, which reach up to 25 $\%$ in the PSP perihelion, the different terms in the compressible exact relation are shown to have different impact in the total cascade rate $\varepsilon_C$. Finally, the observational results are connected with the local ion temperature and the solar wind heating problem.
Matrix realignment and partial transpose approach to entangling power of quantum evolutions
Creators: name: Ma, Zhihao
name: Wang, Xiaoguang
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Based on the matrix realignment and partial transpose, we develop an approach to entangling power and operator entanglement of quantum unitary operators. We demonstrate efficiency of the approach by studying several unitary operators on qudits, and indicate that these two matrix rearrangements are not only powerful for studying separability problem of quantum states, but also useful in studying entangling capabilities of quantum operators.
description: Four pages and no figures
First hitting times between a run-and-tumble particle and a stochastically-gated target
Creators: name: Mercado-Vásquez, Gabriel
name: Boyer, Denis
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study the first hitting time statistics between a one-dimensional run-and-tumble particle and a target site that switches intermittently between visible and invisible phases. The two-state dynamics of the target is independent of the motion of the particle, which can be absorbed by the target only in its visible phase. We obtain the mean first hitting time when the motion takes place in a finite domain with reflecting boundaries. Considering the turning rate of the particle as a tuning parameter, we find that ballistic motion represents the best strategy to minimize the mean first hitting time. However, the relative fluctuations of the first hitting time are large and exhibit non-monotonous behaviours with respect to the turning rate or the target transition rates. Paradoxically, these fluctuations can be the largest for targets that are visible most of the time, and not for those that are mostly invisible or rapidly transiting between the two states. On the infinite line, the classical asymptotic behaviour $\propto t^{-3/2}$ of the first hitting time distribution is typically preceded, due to target intermittency, by an intermediate scaling regime varying as $t^{-1/2}$. The extent of this transient regime becomes very long when the target is most of the time invisible, especially at low turning rates. In both finite and infinite geometries, we draw analogies with partial absorption problems.
description: 5 figures
Conditional Quantum Walk and Iterated Quantum Games
Creators: name: Abal, G.
name: Donangelo, R.
name: Fort, H.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Iterated bipartite quantum games are implemented in terms of the discrete-time quantum walk on the line. Our proposal allows for conditional strategies, as two rational agents make a choice from a restricted set of two-qubit unitary operations. Several frequently used classical strategies give rise to families of corresponding quantum strategies. A quantum version of the Prisoner's Dilemma in which both players use mixed strategies is presented as a specific example. Since there are now quantum walk physical implementations at a proof-of principle stage, this connection may represent a step towards the experimental realization of quantum games.
description: Revtex 4, 6 pages, 3 figures. Expanded version with one more figure and updated references. Abstract was rewritten