cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Rashba-type Dzyaloshinskii-Moriya interaction, perpendicular magnetic anisotropy and skyrmion states at 2D materials/Co interfaces
Creators: name: Hallal, Ali
name: Liang, Jinghua
name: Ibrahim, Fatima
name: Yang, Hongxin
name: Fert, Albert
name: Chshiev, Mairbek
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: We report a significant Dzyaloshinskii-Moriya interaction (DMI) and perpendicular magnetic anisotropy (PMA) at interfaces comprising hexagonal boron nitride (h-BN) and Co. By comparing the behavior of these phenomena at graphene/Co and h-BN/Co interfaces, it is found that the DMI in latter increases as a function of Co thickness and beyond three monolayers stabilizes with one order of magnitude larger values compared to those at graphene/Co, where the DMI shows opposite decreasing behavior. At the same time, the PMA for both systems shows similar trends with larger values for graphene/Co and no significant variations for all thickness ranges of Co. Furthermore, using micromagnetic simulations we demonstrate that such significant DMI and PMA values remaining stable over large range of Co thickness give rise to formation of skyrmions with small applied external fields in the range of 200-250 mT up to 100 K temperatures. These findings open up further possibilities towards integrating two-dimensional (2D) materials in spin-orbitronics devices.
description: 16 pages, 4 figures
Sol-Gel Synthesis and Characterization of pure and doped Transparent and Conductive ZnO Thin Films
Creators: name: Tari, Orlando
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2013

description: In this PhD research activity the Sol-Gel synthesis of transparent and conductive ZnO thin films, suitable for photovoltaic (PV) applications was deeply studied. The most important aspects of the Sol–Gel synthesis of ZnO thin films were analysed. In particular, the effect of the zinc precursor molar concentration on the film properties is focused as well as the effect of the annealing conditions (time, temperature and environment). Furthermore, the influence of the pH level of the precursor solution was investigated. Thanks to an optical, morphological, structural and electrical analysis the best synthesis conditions for ZnO films deposition were established. In these conditions multi-layer ZnO films were prepared in order to increase the film thickness. On these layers Thin Film Solar Cells were deposited and characterized with particular reference to the interface between the TCO and the active layer (a-Si:H p-taype).
Electric quadrupole moment of a neutral non-relativistic particle in the presence of screw dislocation
Creators: name: Hassanabadi, H.
name: Zare, S.
name: Kríž, J.
name: Lütfüoğlu, B. C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this contribution, we investigate the interaction between electric and magnetic fields with an electric quadrupole moment of a spinless particle moving in an elastic medium which has a topological defect (screw dislocation). By considering this interaction, the Schrödinger equation is exactly solved by using the analytical method. Thus, the eigenfunction and energy eigenvalues for two configurations are found. Meanwhile, by observing a shift in the angular momentum quantum number, the energy eigenvalues and the wave function of the system are modified, due to the screw dislocation in the medium.
description: 6 pages, 3 figures
D11.1 Scoping Process Report
Creators: name: Pechsiri, Joseph
name: Monteiro Souza, Alexandre
name: Shigwedha, Paulus
name: Sundberg, Cecilia
name: Ericsson, Niclas
Publisher: name: SteamBioAfrica
Year: 2022
Subjects: subject: Sustainability sciences

description: This deliverable describes the progress of the goal and scope definition of the life cycle studies in SteamBioAfrica (SBA), which is part of work package 11 (WP11).Whenever a new technology is developed, or an old technology is introduced into a new context, concerns about the potential environmental, social, and economic impacts arise. This is also the case for the superheated steam (SHS) technology used to process encroacher bush biomass in southern Africa.

The aim of the life cycle studies is to perform a full life cycle sustainability assessment (LCSA) of future value chains of renewable fuels and chemicals produced from encroacher bush using SHS technology across the three Southern African countries where the project is taking place (Botswana, Namibia, and South Africa). The LCSA includes both an environmental life cycle assessment (E-LCA), a social life cycle assessment (S-LCA) and a life cycle costing (LCC). With LCSA the environmental, social, and economic sustainability of a product or service can be assessed together from a life cycle perspective. This allows the identification of any trade-offs or hotspots when developing the value chains as well as the estimation of potential environmental and socioeconomic impacts from different future value chains in Southern Africa. This will help guide decision makers in their effort to mitigate negative and enhance positive impacts.

There are four phases in a life cycle study: (1) goal and scope definition, (2) inventory analysis, (3) impact assessment and (4) interpretation. The goal and scope definition phase is where the purpose of the study, the object of the study, as well as the methodological framework of the study are determined and described. In other words, it describes why and how the assessment is being done, including any methodological considerations that may affect the outcome and interpretation of the results.

This scoping process report describes the work that has been carried out during the first 12 months of the SBA project with defining the tentative goal and scope, including the intended audience and application, the value chain and its system boundaries, the tentative functional units and scenarios to be assessed as well as the main assumptions and limitations of the life cycle studies. The goal and scope phase is an iterative process. It is continuously revisited and revised as new knowledge is acquired while working with the inventory analysis, impact assessment and interpretation of the results.
The computation of chemical equilibrium and the distribution of Fe, Mn and Mg among sites and phases in olivines and garnets
Creators: name: De Capitani, Christian
Publisher: name: University of British Columbia
Year: 2010

description: A general algorithm for the computation of chemical equilibria in complex systems containing non-ideal solutions has been developed. The method is a G-minimization based on repeated linear and nonlinear programming steps. A computer program (THERIAK) based on this algorithm has been written and was used to solve a great variety of problems, ranging from a simple blast furnace calculation to liquid-liquid unmixing in a four component silicate melt. The computing times are in the magnitude of 1/2 to 2 seconds for each calculation. The method can also be used to test the consequences of thermodynamic models and data in systems of interest to many fields, including chemistry, geochemistry and metallurgy. Integrated powder diffraction intensities can be used to measure Mn-Mg and Fe-Mg site occupancies in olivines because of the difference in scattering factors between Mg and Mn or Fe. Theoretically calculated intensity ratios are subject to uncertainties from positional parameters (less than 3.5 % for peaks with a relative intensity greater than 25 %) and unknown charge distribution (up to 30 %). Several peak ratios are less subject to this last uncertainty and may be used to measure the site occupancies in olivines. 27 synthetic Fe-Mn-Mg olivines (800 °C, vacuum, with graphite) were investigated with Mossbauer spectroscopy and XRD intensity evaluation, producing occupancies accurate to approximately 0.03 per site. A thermodynamic speciation model represents the data very well. Preliminary Fe-Mn-Mg exchange experiments involving olivine and garnet place some limits on element distributions between these two minerals.
Reducing variance in univariate smoothing
Creators: name: Cheng, Ming-Yen
name: Peng, Liang
name: Wu, Jyh-Shyang
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: 62G08, 62G05 (Primary); 60G20 (Secondary)

description: A variance reduction technique in nonparametric smoothing is proposed: at each point of estimation, form a linear combination of a preliminary estimator evaluated at nearby points with the coefficients specified so that the asymptotic bias remains unchanged. The nearby points are chosen to maximize the variance reduction. We study in detail the case of univariate local linear regression. While the new estimator retains many advantages of the local linear estimator, it has appealing asymptotic relative efficiencies. Bandwidth selection rules are available by a simple constant factor adjustment of those for local linear estimation. A simulation study indicates that the finite sample relative efficiency often matches the asymptotic relative efficiency for moderate sample sizes. This technique is very general and has a wide range of applications.
description: Published at http://dx.doi.org/10.1214/009053606000001398 in the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org)
On the surface brightness radial profile of the extended $γ$-ray sources
Creators: name: Yang, Rui-zhi
name: Liu, Bing
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The morphology of the extended $γ$-ray source is governed by the propagation process of parent relativistic particles. In this paper, we investigate the surface brightness radial profile of extended $γ$-ray sources illuminated by cosmic ray protons and electrons, considering the radiation mechanisms, projection effects, and the response of instruments. We found that the parent particle species and the propagation process can cause considerable differences in the observed radial profiles. Thus, the surface brightness profile can be used as a unique tool to identify the radiation mechanism and the propagation process of the parent particles. In addition, We also discuss the possible implications regarding the latest discoveries from very/ultra-high energy $γ$-ray instruments like LHAASO and HAWC.
description: Accepted for publication in SCIENCE CHINA Physics, Mechanics & Astronomy (SCPMA)
The chromosome-level genome assembly of the giant dobsonfly Acanthacorydalis orientalis (McLachlan, 1899)
Creators: name: 邹, 明明
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 310509
subject: Genomics

description: The genome annotation GFF, CDS sequences, and protein sequences
Higgs Boson Exempt No-Scale Supersymmetry with a Neutrino Seesaw: Implications for Lepton Flavor Violation and Leptogenesis
Creators: name: Chun, Eung Jin
name: Evans, Jason L.
name: Morrissey, David E.
name: Wells, James D.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Motivated by the observation of neutrino oscillations, we extend the Higgs boson exempt no-scale supersymmetry model (HENS) by adding three heavy right-handed neutrino chiral supermultiplets to generate the light neutrino masses and mixings. The neutrino Yukawa couplings can induce new lepton flavor violating couplings among the soft terms in the course of renormalization group running down from the boundary scale. We study the effects this has on the predictions for low-energy probes of lepton flavor violation(LFV). Heavy right-handed neutrinos also provide a way to generate the baryon asymmetry through leptogenesis. We find that consistency with LFV and leptogenesis puts strong requirements on either the form of the Yukawa mass matrix or the smallness of the Higgs up soft mass. In all cases, we generically expect that new physics LFV is non-zero and can be found in a future experiment.
description: 25 pages, 11 figures; Added a reference
On Gribov's supercriticality picture of quark confinement
Creators: name: Fischer, Christian S.
name: Nickel, Dominik
name: Williams, Richard
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Some years ago Gribov developed the so-called supercritical light quark confinement scenario. Based on physical arguments he conjectured a drastic change in the analytical properties of the quark propagator when the back-reaction of Goldstone bosons (pions) is considered. We investigate this scenario and provide numerical solutions for the quark propagator in the complex plane with and without the pion back-reaction. We find no evidence for the scenario Gribov advocated. As an aside we present a novel method to solve the quark Dyson-Schwinger equation in the complex plane and discuss new characteristics of dynamical chiral symmetry breaking in our truncation scheme.
description: 21 pages, 12 figures. Version to appear in EPJC
Bigravity and Lorentz-violating Massive Gravity
Creators: name: Blas, D.
name: Deffayet, C.
name: Garriga, J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Bigravity is a natural arena where a non-linear theory of massive gravity can be formulated. If the interaction between the metrics $f$ and $g$ is non-derivative, spherically symmetric exact solutions can be found. At large distances from the origin, these are generically Lorentz-breaking bi-flat solutions (provided that the corresponding vacuum energies are adjusted appropriately). The spectrum of linearized perturbations around such backgrounds contains a massless as well as a massive graviton, with {\em two} physical polarizations each. There are no propagating vectors or scalars, and the theory is ghost free (as happens with certain massive gravities with explicit breaking of Lorentz invariance). At the linearized level, corrections to GR are proportional to the square of the graviton mass, and so there is no vDVZ discontinuity. Surprisingly, the solution of linear theory for a static spherically symmetric source does {\em not} agree with the linearization of any of the known exact solutions. The latter coincide with the standard Schwarzschild-(A)dS solutions of General Relativity, with no corrections at all. Another interesting class of solutions is obtained where $f$ and $g$ are proportional to each other. The case of bi-de Sitter solutions is analyzed in some detail.
description: 25 pages. v3 Typos corrected, references added. v4 Introduction extended
Proposal for exotic-hadron search by fragmentation functions
Creators: name: Hirai, M.
name: Kumano, S.
name: Oka, M.
name: Sudoh, K.
Publisher: name: arXiv
Year: 2007
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: It is proposed that fragmentation functions should be used to identify exotic hadrons. As an example, fragmentation functions of the scalar meson f_0(980) are investigated. It is pointed out that the second moments and functional forms of the u- and s-quark fragmentation functions can distinguish the tetraquark structure from $q\bar q$. By the global analysis of f_0 (980) production data in electron-positron annihilation, its fragmentation functions and their uncertainties are determined. It is found that the current available data are not sufficient to determine its internal structure, while precise data in future should be able to identify exotic quark configurations.
description: 4 pages, 4 figures, revtex, To be published in PRD
Search for period changes in Mira stars
Creators: name: Nesci, Roberto
name: Rocchi, Gianni
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We reobserved in the $R_C$ and $i'_{Sloan}$ bands, during the years 2020-2021, seven Mira variables in Cassiopeia, for which historical $i'_{Sloan}$ light curves were available from Asiago Observatory plates taken in the years 1967-84. The aim was to check if any of them had undergone a substantial change in the period or in the light curve shape. Very recent public data form ZTF-DR5 were also used to expand our time base window. A marked color change was detected for all the stars along their variability cycle. The star V890 Cas showed a significant period decrease of 12\% from 483 to 428 days, one of the largest known to date. All the stars, save AV Cas, showed a smaller variation amplitude in the recent CCD data, possibly due to a photometric accuracy higher than that of the photographic plates.
description: 12 pages, 8 figures, accepted for Open European Journal on Variable Stars (OEJV)
Mirrorless Negative-index Parametric Micro-oscillator
Creators: name: Popov, Alexander K.
name: Myslivets, Sergei A.
name: Shalaev, Vladimir M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The feasibility and extraordinary properties of mirrorless parametric oscillations in strongly absorbing negative-index metamaterials are shown. They stem from the backwardness of electromagnetic waves inherent to this type of metamaterials.
description: 4 pages, 2 figures
On the N=1 super Liouville four-point functions
Creators: name: Belavin, V. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct the four-point correlation functions containing the top component of the supermultiplet in the Neveu-Schwarz sector of the N=1 SUSY Liouville field theory. The construction is based on the recursive representation for the NS conformal blocks. We test our results in the case where one of the fields is degenerate with a singular vector on the level 3/2. In this case, the correlation function satisfies a third-order ordinary differential equation, which we derive. We numerically verify the crossing symmetry relations for the constructed correlation functions in the nondegenerate case.
description: 23 pages
Dark energy and cosmic curvature: Monte-Carlo Markov Chain approach
Creators: name: Gong, Yungui
name: Wu, Qiang
name: Wang, Anzhong
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We use the Monte-Carlo Markov Chain method to explore the dark energy property and the cosmic curvature by fitting two popular dark energy parameterizations to the observational data. The new 182 gold supernova Ia data and the ESSENCE data both give good constraint on the DE parameters and the cosmic curvature for the dark energy model $w_0+w_a z/(1+z)$. The cosmic curvature is found to be $|Ω_k|\la 0.03$. For the dark energy model $w_0+w_a z/(1+z)^2$, the ESSENCE data gives better constraint on the cosmic curvature and we get $|Ω_k|\leq 0.02$.
description: 10 figures, revised version: clarify the marginalization on H_0 and the use of the covariance matrix, accepted for publication in ApJ
La baroquisation du monde. Iconophilie ed clair-obscur dans l’imaginaire post-moderne
Creators: name: Maffesoli, Michel
Publisher: name: ECHO
Year: 2021
Subjects: Imaginaire; baroque; post-modernité; esthétique; vie quotidienne; Imaginary; baroque; post-modernity; aesthetics; everyday life

description: The figures of speech of a society are never identically repeated, as neither artistic nor fashion styles are. Each era draws from the stock of knowledge of the past and metabolizes it. In this sense, our time is a curious mixture of exemplarist mysticism and baroque futility, of Franciscan asceticism and baroque luxuriance, of thirteenth-century paracletism and Jesuit accommodation to the world. By all means, it is a question of expressing, from day to day and in all the works of life, this interaction between reason and senses, the "sensitive reason". From there, this is how, from "noon to midnight", the light and the darkness of life flow in a dynamic that is always and again renewed. This is what I have called the postmodern baroque. A style that instead of cutting off the past, of taking the via recta of reason, adjusts itself to the meanders of existence and integrates the past instead of de-passing it. Les figures de style d’une société ne se répètent jamais à l’identique, comme d’ailleurs les styles artistiques ou les modes vestimentaires. Chaque époque puise dans le stock de connaissances du passé et le métabolise. En ce sens notre époque est un curieux mixte de la mystique exemplariste et de la futilité baroque, de l’ascétisme franciscain et de la luxuriance baroque, du paracletisme du XIIIe siècle et de l’accommodement au monde jésuite. Par tous les moyens, il s’agit d’exprimer, au jour le jour et dans toutes les œuvres de la vie cette interaction entre raison et sens, la « raison sensible ». À partir de là, voici comment, de « midi à minuit », ce sont le clair et l’obscur de la vie qui s’écoulent en une dynamique toujours et à nouveau renouvelée. C’est cela que j’ai nommé le baroque postmoderne. Un style qui au lieu de couper le passé, d’emprunter la via recta de la raison, s’ajuste aux méandres de l’existence et intègre le passé au lieu de le dé-passer.
description: ECHO, N. 3 (2021): Lo statuto dell’immagine nel XXI secolo: schermi, rappresentazioni, sparizioni
Tremblements sociaux et imaginaires. De la peau digitale aux fissures numériques
Creators: name: Joron, Philippe
Publisher: name: ECHO
Year: 2021
Subjects: Imaginaire; culture numérique; communication; altérité; être-ensemble; Imaginary; digital culture; communication; otherness; being-together

description: This study questions our capacity to exceed and/or bury our condition of ‘been thrown there’, and/or to find duplicate zones of navigability (i.e. adaptable) to express our general malaise, in the in-between of the wounds and the pleasures supporting our existence. On a methodological level, ‘we’, in the Simmelian sense, is used as an inclusive term. It is a line of intellectual action which does not claim to be approved. It simply says the "I" in a search for continuity with what is not him, or the purulent saturation of the knowing subject in the discovery of the object that echoes its interpellations and feeds it. L’étude présentée ici sous forme d’essai interroge notre capacité à dépasser et/ou enfouir notre condition de “jeté-là”, et/ou à trouver des zones de navigabilité duplices, c’est-à-dire adaptables, pour exprimer le malaise générique qui nous fait, dans l’entre-deux des blessures et des plaisirs mettant en soutien notre existence. Sur un plan méthodologique, l’emploi du “nous” se veut inclusif, modal au sens simmelien. Il est une ligne d’action intellectuelle qui ne réclame en rien l’approbation. Il dit simplement le “je” dans une recherche de continuité avec ce qui n’est pas lui, ou bien la saturation purulente du sujet connaissant dans la découverte de l’objet qui fait écho à ses interpellations et l’alimente.
description: ECHO, N. 3 (2021): Lo statuto dell’immagine nel XXI secolo: schermi, rappresentazioni, sparizioni
Observation of hydrogen-induced Dzyaloshinskii-Moriya interaction and reversible switching of magnetic chirality
Creators: name: Chen, Gong
name: Robertson, MacCallum
name: Hoffmann, Markus
name: Ophus, Colin
name: Cauduro, Andre L. Fernandes
name: Conte, Roberto Lo
name: Ding, Haifeng
name: Wiesendanger, Roland
name: Blügel, Stefan
name: Schmid, Andreas K.
name: Liu, Kai
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The Dzyaloshinskii-Moriya interaction (DMI) has drawn great attention as it stabilizes magnetic chirality, with important implications in fundamental and applied research. This antisymmetric exchange interaction is induced by the broken inversion symmetry at interfaces or in non-centrosymmetric lattices. Significant interfacial DMI was found often at magnetic / heavy-metal interfaces with large spin-orbit coupling. Recent studies have shown promise of induced DMI at interfaces involving light elements such as carbon (graphene) or oxygen. Here we report direct observation of induced DMI by chemisorption of the lightest element, hydrogen, on a ferromagnetic layer at room temperature, which is supported by density functional theory calculations. We further demonstrate a reversible chirality transition of the magnetic domain walls due to the induced DMI via hydrogen chemisorption/desorption. These results shed new light on the understanding of DMI in low atomic number materials and design of novel chiral spintronics and magneto-ionic devices.
description: 20 pages, 3 figures. 3 pages Supplemental Materials with 2 figures. To appear in Physical Review X
Reconstruction from Radon projections and orthogonal expansion on a ball
Creators: name: Xu, Yuan
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 42A38, 42B08, 42B15

description: The relation between Radon transform and orthogonal expansions of a function on the unit ball in $\RR^d$ is exploited. A compact formula for the partial sums of the expansion is given in terms of the Radon transform, which leads to algorithms for image reconstruction from Radon data. The relation between orthogonal expansion and the singular value decomposition of the Radon transform is also exploited.
description: 15 pages
Immagini, toni, emozioni: per una città “instagrammata”
Creators: name: La Rocca, Fabio
Publisher: name: ECHO
Year: 2021
Subjects: città; immagini; emozioni; ambiente digitale; instagram ; city; images; emotions; digital environment; instagram

description: We are increasingly contaminated by images marked by an accelerated digital reproducibility that generates the incessant movement and directions of multiple visual signs through the panoply of screen devices. We are faced with a world that is increasingly becoming image and reflection, a world of shared images, exchanged in the simultaneity of emotional flows effected by an interactivity of the digital environment with urban space. Within this context, the present paper focuses on the emergence of an instagrammed city, which can be seen as an archetypal form of visual reproduction of urban spaces and their atmospheres. La nostra contemporaneità è contaminata dalla presenza crescente delle immagini contraddistinta da un’accelerata riproducibilità digitale che genera l’incessante movimento dei molteplici segni visuali attraverso la panoplia dei dispositivi schermatici. Siamo di fronte a un mondo che diventa sempre più immagine e riflesso, un mondo di immagini condivise, scambiate nella simultaneità dei flussi emotivi condizionati dall’interattività tra spazi digitali e spazi urbani. In questa perspettiva, la nostra riflessione si basa sull’emergenza di un immaginario della “città instragrammata” come forma archetipa di una produzione visuale degli spazi urbani e le loro atmosfere.
description: ECHO, N. 3 (2021): Lo statuto dell’immagine nel XXI secolo: schermi, rappresentazioni, sparizioni
Computational Simulation and 3D Virtual Reality Engineering Tools for Dynamical Modeling and Imaging of Composite Nanomaterials
Creators: name: Bochkareva, L. -V.
name: Kireitseu, M. -V.
name: Tomlinson, G. R.
name: Altenbach, H.
name: Kompis, V.
name: Hui, D.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: An adventure at engineering design and modeling is possible with a Virtual Reality Environment (VRE) that uses multiple computer-generated media to let a user experience situations that are temporally and spatially prohibiting. In this paper, an approach to developing some advanced architecture and modeling tools is presented to allow multiple frameworks work together while being shielded from the application program. This architecture is being developed in a framework of workbench interactive tools for next generation nanoparticle-reinforced damping/dynamic systems. Through the use of system, an engineer/programmer can respectively concentrate on tailoring an engineering design concept of novel system and the application software design while using existing databases/software outputs.
description: Submitted on behalf of TIMA Editions (http://irevues.inist.fr/tima-editions)
#100PCI: un percorso di ricerca sulle pratiche visive e memoriali
Creators: name: Villani, Claudia
Publisher: name: ECHO
Year: 2021
Subjects: Immaginario; cultura visuale; memoria; comunismo; partito Comunista Italiano imagery; visual culture; memory; communism; Italian Communist Party

description: The article explores the communist visual culture expressed on Twitter and Instagram on the occasion of the Italian Communist Party centenary. The aim is to bring out characters, meanings and interpretative problems around individual and collective processes of memorialization, as they manifest themselves in peculiar communicative contexts. Here, the communist visual culture is considered, in line with recent studies, as an essential part of everyday culture and lived experience, and as a symbolic signifier that expresses particular "memories of the future". L'articolo esplora la cultura visuale comunista espressa in occasione del centenario della nascita del partito comunista italiano su Twitter e Instagram. L’obiettivo è avviare una riflessione su caratteri, significati e problemi interpretativi intorno ai processi di memorializzazione, individuali e collettivi, per come si manifestano in contesti comunicativi peculiari. La cultura visuale comunista viene qui considerata, in linea con recenti studi, come parte essenziale della cultura quotidiana e dell’esperienza vissuta e come significante o collante simbolico che esprime particolari “memorie del futuro”.
description: ECHO, N. 3 (2021): Lo statuto dell’immagine nel XXI secolo: schermi, rappresentazioni, sparizioni
Attack on practical speaker verification system using universal adversarial perturbations
Creators: name: Zhang, Weiyi
name: Zhao, Shuning
name: Liu, Le
name: Li, Jianmin
name: Cheng, Xingliang
name: Zheng, Thomas Fang
name: Hu, Xiaolin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Sound (cs.SD)
subject: Artificial Intelligence (cs.AI)
subject: Audio and Speech Processing (eess.AS)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: In authentication scenarios, applications of practical speaker verification systems usually require a person to read a dynamic authentication text. Previous studies played an audio adversarial example as a digital signal to perform physical attacks, which would be easily rejected by audio replay detection modules. This work shows that by playing our crafted adversarial perturbation as a separate source when the adversary is speaking, the practical speaker verification system will misjudge the adversary as a target speaker. A two-step algorithm is proposed to optimize the universal adversarial perturbation to be text-independent and has little effect on the authentication text recognition. We also estimated room impulse response (RIR) in the algorithm which allowed the perturbation to be effective after being played over the air. In the physical experiment, we achieved targeted attacks with success rate of 100%, while the word error rate (WER) on speech recognition was only increased by 3.55%. And recorded audios could pass replay detection for the live person speaking.
description: 6 pages, 2 figures
Frequency locking in the injection-locked frequency divider equation
Creators: name: Bartuccelli, Michele V.
name: Deane, Jonathan H. B.
name: Gentile, Guido
Publisher: name: arXiv
Year: 2008
Subjects: subject: Dynamical Systems (math.DS)
subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: 34C23, 34C25, 37C10, 37C60, 37G15

description: We consider a model for the injection-locked frequency divider, and study analytically the locking onto rational multiples of the driving frequency. We provide explicit formulae for the width of the plateaux appearing in the devil's staircase structure of the lockings, and in particular show that the largest plateaux correspond to even integer values for the ratio of the frequency of the driving signal to the frequency of the output signal. Our results prove the experimental and numerical results available in the literature.
description: 20 figures, 2 figures
Grupo de Investigación GRIAL de la Universidad de Salamanca
Creators: name: García-Peñalvo, F. J.
Publisher: name: Zenodo
Year: 2019
Subjects: GRIAL; Grupo de investigación; Líneas de investigación; Proyectos de investigación; Servicios

description: Presentación del Grupo GRIAL realizada el 17 de junio de 2019 dentro del Programa “Visita de Investigador de Impacto Internacional” de la Universidad Nacional de San Agustín (Perú).
Determination of the spin Hall angle by the inverse spin Hall effect, device level ferromagnetic resonance, and spin torque ferromagnetic resonance: a comparison of methods
Creators: name: Ben-Shalom, Ranen
name: Bernstein, Nirel
name: Yang, See-Hun
name: Capua, Amir
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The spin torque ferromagnetic resonance (STFMR) is one of the popular methods for measurement of the spin Hall angle (SHA). However, in order to accurately determine SHA from STFMR measurements, the acquired data must be carefully analyzed: The resonance linewidth should be determined to an accuracy of a fraction of an Oe, while the dynamical interaction leading to the measured response consists of the conventional field-induced ferromagnetic resonance (FMR), spin-torque induced FMR, and of the inverse spin Hall effect (ISHE). Additionally, the signal often deteriorates when DC current is passed through the device. In this work we compare the STFMR method with two other FMR-based methods that are used to extract SHA. The first is a device-level FMR and the second is based on the ISHE. We identify artefacts that are caused by the noise floor of the instrumentation that make the measurement of SHA illusive even when the signal to noise ratio seems to be reasonable. Additionally, we estimate a 10% error in SHA that results from neglecting the magnetic anisotropies as in conventional measurements. Overall, we find the STFMR to be the most robust of the three methods despite the complexity of the interaction taking place therein. The conclusions of our work lead to a more accurate determination of SHA and will assist in the search of novel materials for energy efficient spin-based applications.
Design, synthesis and molecular mechanisms of novel dual inhibitors of heat shock protein 90/phosphoinositide 3-kinase alpha (Hsp90/PI3Kα) against cutaneous melanoma
Creators: name: Qin, Feifei
name: Wang, Yali
name: Jiang, Xian
name: Wang, Yujia
name: Zhang, Nan
name: Wen, Xiang
name: Wang, Lian
name: Jiang, Qinglin
name: He, Gu
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Pharmacology
subject: Biotechnology
subject: Chemical Sciences not elsewhere classified
subject: Biological Sciences not elsewhere classified
subject: Information Systems not elsewhere classified
subject: Developmental Biology
subject: Cancer
subject: Hematology

description: Overexpression of heat shock protein 90 (Hsp90) is common in various types of cancer. In cutaneous melanoma, a cancer with one of the high levels of Hsp90 overexpression, such expression was correlated with a panel of protein kinases, thus offering an opportunity to identify Hsp90-based multi-kinase inhibitors for novel cancer therapies. Towards this goal, we utilized a 2,4-dihydroxy-5-isopropylbenzate-based Hsp90 inhibitor scaffold and thieno[2,3-d]pyrimidine-based kinase inhibitor scaffold to develop a Hsp90-inhibiting compound library. Our inhibitory compound named 8m inhibited Hsp90 and PI3Kα with an IC50 value of 38.6 nM and 48.4 nM, respectively; it displayed improved cellular activity which could effectively induce cell cycle arrest and apoptosis in melanoma cells and lead to the inhibition of cell proliferation, colony formation, migration and invasion. Our results demonstrated 8m to be a promising lead compound for further therapeutic potential assessment of Hsp90/PI3Kα dual inhibitors in melanoma targeted therapy.
Measurement-based quantum heat engine in a multilevel system
Creators: name: Anka, Maron F.
name: de Oliveira, Thiago R.
name: Jonathan, Daniel
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We compare quantum Otto engines based on two different cycle models: a two-bath model, with a standard heat source and sink, and a measurement-based protocol, where the role of heat source is played by a quantum measurement. We furthermore study these cycles using two different `working substances': a single qutrit (spin-1 particle) or a pair of qubits (spin-1/2 particles) interacting via the XXZ Heisenberg interaction. Although both cycle models have the same efficiency when applied on a single-qubit working substance, we find that both can reach higher efficiencies using these more complex working substances, by exploiting the existence of `idle' levels, i.e., levels that do not shift while the spins are subjected to a variable magnetic field. Furthermore, with an appropriate choice of measurement, the measurement-based protocol becomes more efficient than the two-bath model.
description: 12 pages, 7 figures
The meeting problem in the quantum random walk
Creators: name: Stefanak, M.
name: Kiss, T.
name: Jex, I.
name: Mohring, B.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study the motion of two non-interacting quantum particles performing a random walk on a line and analyze the probability that the two particles are detected at a particular position after a certain number of steps (meeting problem). The results are compared to the corresponding classical problem and differences are pointed out. Analytic formulas for the meeting probability and its asymptotic behavior are derived. The decay of the meeting probability for distinguishable particles is faster then in the classical case, but not quadratically faster. Entangled initial states and the bosonic or fermionic nature of the walkers are considered.
Tornado-Like Vortices in the Quasi-Cyclostrophic Regime of Coriolis-Centrifugal Convection
Creators: name: Horn, Susanne
name: Aurnou, Jonathan M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Coriolis-centrifugal convection (C$^3$) in a cylindrical domain constitutes an idealised model of tornadic storms, where the rotating cylinder represents the mesocyclone of a supercell thunderstorm. We present a suite of C$^3$ direct numerical simulations, analysing the influence of centrifugal buoyancy on the formation of tornado-like vortices (TLVs). TLVs are self-consistently generated provided the flow is within the quasi-cyclostrophic (QC) regime. This requires the Froude number to be greater than the radius-to-height aspect ratio, $Fr \gtrsim γ$. We show that the TLVs share many features with realistic tornadoes, such as azimuthal velocity profiles, intensification of the vortex strength, and helicity characteristics. Further, we analyse the influence of the mechanical bottom boundary conditions on the formation of TLVs, finding that a rotating fluid column above a stationary surface does not generate TLVs if centrifugal buoyancy is absent. In contrast, TLVs are generated in the QC regime with any bottom boundary conditions when centrifugal buoyancy is present. Our simulations bring forth insights into natural supercell thunderstorm systems by identifying properties that determine whether a mesocyclone becomes tornadic or remains non-tornadic. Our $Fr \gtrsim γ$ predictions dimensionally imply a critical mesocyclone angular rotation rate of $\widetildeΩ_{mc} \gtrsim \sqrt{g/H_{mc}}$. Taking a typical mesocyclone height of $H_{mc}\approx 12$ km, this translates to $\widetildeΩ_{mc}\gtrsim 3~\times~10^{-2}$s$^{-1}$ for centrifugal buoyancy-dominated, quasi-cyclostrophic tornadogenesis. The formation of the simulated TLVs happens at all heights on the centrifugal buoyancy time scale $τ_{cb}$. This implies a roughly 1 minute, height-invariant formation for natural tornadoes, consistent with recent observational estimates.
description: This article has been accepted for publication in the Journal of Turbulence, published by Taylor & Francis
Di lotta e di governo. I digital fashion influencer e l’immaginario di moda
Creators: name: Pedroni, Marco
Publisher: name: ECHO
Year: 2021
Subjects: moda; digital influencer; autenticità; immaginario di moda; fashion; digital influencers; authenticity; fashion imaginary

description: The essay focuses on the phenomenon of fashion blogging and influencing, and analyses how the work of digital influencers affects the production and circulation of fashion imaginary. The aim of the contribution is twofold. Firstly, to show the institutionalisation of fashion blogging and influencing through a "fight and rule" strategy: trying to maintain, at least rhetorically, the appeal of the outsider voice born from below, bloggers and influencers are now a structural component of the communicative processes that link brands and consumers. Secondly, to identify the contribution of fashion blogging and influencing to the construction/deconstruction of the contemporary fashion imaginary. The article develops a case study, that of the most successful Italian digital influencer: Chiara Ferragni, author of The Blonde Salad, who counts more than 24 million followers on Instagram (September 2021). The initial phase of Ferragni's "career" (2009-2016) is reconstructed. The categories of "fashion imaginary" and "alternative media" are used to understand to what extent the dominant fraction of bloggers, represented by the influencer Ferragni, was (and is) able to feed the contemporary fashion imaginary with alternative narratives. Il saggio si occupa del fenomeno del fashion blogging e influencing, analizzando in che modo il lavoro dei digital influencer influenza la produzione e la circolazione dell’immaginario di moda. L’obiettivo del contruibuto è duplice. In primo luogo, mostrare l’avvenuta istituzionalizzazione del fashion blogging e influencing attraverso una strategia «di lotta e di governo»: cercando di mantenere, almeno retoricamente, il fascino della voce outsider e nata dal basso, i blogger e gli influencer sono ormai una componente strutturale dei processi comunicativi che collegano brand e consumatori. In secondo luogo, identificare il contributo del fashion blogging e influencing alla costruzione/decostruzione dell’immaginario di moda contemporaneo. L’articolo sviluppa uno studio di caso, quello della digital influencer italiana di maggior successo: Chiara Ferragni, volto di The Blonde Salad e instagrammer con oltre 24 milioni di follower (settembre 2021). Di Ferragni è ricostruita la fase iniziale della «carriera», tra il 2009 e 2016. Le categorie di «immaginario di moda» e «media alternativi» vengono utilizzate per comprendere in che misura la frazione dominante dei blogger, rappresentata dall’influencer Ferragni, sia stata (e sia) in grado di alimentare l’immaginario della moda contemporanea con narrazioni alternative.
description: ECHO, N. 3 (2021): Lo statuto dell’immagine nel XXI secolo: schermi, rappresentazioni, sparizioni
Lead and strontium isotope study of five volcanic and intrusive rock suites and related mineral deposits, Vancouver Island, British Columbia
Creators: name: Andrew, Anne
Publisher: name: University of British Columbia
Year: 2010

description: Lead isotope compositions have been obtained from five major volcanic and intrusive rock suites and several ore deposits on Vancouver Island. Lead, uranium and thorium concentrations and strontium isotope ratios have been obtained for a subset of these samples. The rock suites examined are the Paleozoic Sicker Group, Triassic Karmutsen Formation, Jurassic Island Intrusions and Bonanza Group volcanic rocks, and the Eocene Catface intrusions. Isotope geochemistry of the Sicker Group is consistent with the interpretation that it formed as an island arc. Relatively high 207pb/204pb ratios indicate sediment involvement in the subduction process, which suggests that the Sicker Group formed close to a continent. Buttle Lake ore deposits display decreasingly radiogenic lead isotope ratios with time, suggesting that the associated magmas become increasingly primitive. This supports the hypothesis that these deposits formed during the establishment of rifting in a back-arc environment. Karmutsen Formation flood basalts display isotopic mixing between an ocean island-type mantle source and average crust. Isotopic evidence is used to support a Northern Hemisphere origin for these basalts. Mixing is apparent in the lead and strontium isotope signatures of the Island Intrusions and Bonanza Group volcanic rocks, between depleted mantle and crustal (possibly trench sediments) components. This is consistent with formation of these rocks in an island arc environment. Eocene Catface intrusions have relatively high 207pb/204pb indicating that crustal material was involved in their formation. There are two groups of plutons corresponding to an east belt and west belt classification. Galena from the Zeballos mining camp related to the Eocene Zeballos pluton indicates that the mineralization was derived from the pluton. Galena lead isotope data from Vancouver Island may be interpreted in a general way by comparison with data from deposits elsewhere of known age and origin. No single growth curve model can be applied. Lead isotope characteristics of Vancouver Island are clearly different from those of the North American craton, reflecting the oceanic affinities of this terrane. A new technique has been developed to compare 207pb/204pb ratios between samples with differing 206pb/204pb ratios. The procedure projects 207pb/204pb ratios along suitable isochrons until they intersect a reference value of 206pb/204pb. This technique can be used for interpreting lead isotope data from old terranes, in which lead and uranium may have undergone loss or gain, and if lead and uranium abundances have not been measured.