cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Symmetry- and curvature effects on spin waves in vortex-state hexagonal nanotubes
Creators: name: Körber, Lukas
name: Zimmermann, Michael
name: Wintz, Sebastian
name: Finizio, Simone
name: Kronseder, Matthias
name: Bougeard, Dominique
name: Dirnberger, Florian
name: Weigand, Markus
name: Raabe, Jörg
name: Otálora, Jorge A.
name: Schultheiss, Helmut
name: Josten, Elisabeth
name: Lindner, Jürgen
name: Kézmárki, István
name: Back, Christian H.
name: Kákay, Attila
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Analytic and numerical studies on curved magnetic nano-objects predict numerous exciting effects that can be referred to as magneto-chiral effects, which do not originate from intrinsic Dzyaloshinskii-Moriya interaction or interface-induced anisotropies. In constrast, these chiral effects stem from isotropic exchange or dipole-dipole interaction, present in all magnetic materials, which acquire asymmetric contributions in case of curved geometry of the specimen. As a result, for example, the spin-wave dispersion in round magnetic nanotubes becomes asymmetric, namely spin waves of the same frequency propagating in opposite directions along the nanotube exhibit different wavelenghts. Here, using time-resolved scanning transmission X-ray microscopy experiments, standard micromagntic simulations and a dynamic-matrix approach, we show that the spin-wave spectrum undergoes additional drastic changes when transitioning from a continuous to a discrete rotational symmetry, i.e. from round to hexagonal nanotubes, which are much easier to fabricate. The polygonal shape introduces localization of the modes both to the sharp, highly curved corners and flat edges. Moreover, due to the discrete rotational symmetry, the degenerate nature of the modes with azimuthal wave vectors known from round tubes is partly lifted, resulting in singlet and duplet modes. For comparison with our experiments, we calculate the microwave absorption from the numerically obtained mode profiles which shows that a dedicated antenna design is paramount for magnonic applications in 3D nano-structures. To our knowledge these are the first experiments directly showing real space spin-wave propagation in 3D nano objects.
A Review of Electronic Transport in Superconducting Sr$_2$RuO$_4$ Junctions
Creators: name: Anwar, Muhammad Shahbaz
name: Robinson, Jason W. A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We review electronic transport in superconducting junctions with Sr$_2$RuO$_4$. Transport measurements provide evidence for chiral domain walls and, therefore, chiral superconductivity in superconducting Sr$_2$RuO$_4$, but so far, the symmetry of the underlying superconducting state remains inconclusive. Further studies involving density of states measurements and spin-polarised transport in local/non--local Sr$_2$RuO$_4$ junctions with magnetic materials could lead to fundamental discoveries and a better understanding of the superconducting state.
First Frequency-Time-Resolved Imaging Spectroscopy Observations of Solar Radio Spikes
Creators: name: Clarkson, Daniel L.
name: Kontar, Eduard P.
name: Gordovskyy, Mykola
name: Chrysaphi, Nicolina
name: Vilmer, Nicole
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Solar radio spikes are short duration and narrow bandwidth fine structures in dynamic spectra observed from GHz to tens of MHz range. Their very short duration and narrow frequency bandwidth are indicative of sub-second small-scale energy release in the solar corona, yet their origin is not understood. Using the LOw Frequency ARray (LOFAR), we present spatially, frequency and time resolved observations of individual radio spikes associated with a coronal mass ejection (CME). Individual radio spike imaging demonstrates that the observed area is increasing in time and the centroid positions of the individual spikes move superluminally parallel to the solar limb. Comparison of spike characteristics with that of individual Type IIIb striae observed in the same event show similarities in duration, bandwidth, drift rate, polarization and observed area, as well the spike and striae motion in the image plane suggesting fundamental plasma emission with the spike emission region on the order of ${\sim}\:10^8$ cm, with brightness temperature as high as $10^{13}$ K. The observed spatial, spectral, and temporal properties of the individual spike bursts are also suggesting the radiation responsible for spikes escapes through anisotropic density turbulence in closed loop structures with scattering preferentially along the guiding magnetic field oriented parallel to the limb in the scattering region. The dominance of scattering on the observed time profile suggests the energy release time is likely to be shorter than what is often assumed. The observations also imply that the density turbulence anisotropy along closed magnetic field lines is higher than along open field lines.
description: Accepted for publication in the Astrophysical Journal Letters (on 4 Aug 2021), 8 pages, 5 figures
Investigating the influence of changing ice surfaces on gravity wave formation and glacier boundary-layer flow with large-eddy simulations
Creators: name: Goger, Brigitta
name: Nicholson, Lindsey
name: Ouy, Matthis
name: Stiperski, Ivana
Publisher: name: ETH Zurich
Year: 2024

description: Mountain glaciers are located in highly complex terrain and their local micro-climate is influenced by mountain boundary layer processes and dynamically-induced gravity waves. Observations (turbulence flux towers) and simulations (large-eddy simulation) over the Hintereisferner (HEF) glacier in the Austrian Alps have shown that down-glacier winds are often disturbed by cross-glacier flow from the North-West associated with gravity waves. In this work, we explore how the glaciers located upstream of HEF influence the gravity wave formation and intensity and and the feedback this has on boundary layer flow over HEF. In semi-idealized large-eddy simulations, we explore the impact of changing surface properties on HEF's microclimate by removing the upstream glaciers only (NO_UP) and removing all ice surfaces (NO_GL). Simulations suggest that removing the upstream glaciers (which causes a change of boundary layer stratification from stable to unstable) leads to a weaker gravity wave breaking earlier than in the reference simulation and leading to enhanced turbulent mixing over HEF. As a consequence, this results in higher temperatures, sensible heat fluxes, and stronger warm-air advection over HEF tongue. Removing all glaciers results – as expected – in higher temperatures of up to 5 K over the missing ice surfaces, while the gravity wave pattern is similar as in the NO_UP simulation, indicating that the upstream boundary layer exerts dominant control over downstream response in such highly dynamic conditions. This study shows that a single glacier tongue is never isolated from its environment and that surrounding glaciers and local topography have to be taken into account when studying glacier boundary-layer processes. Furthermore, glaciers have a stabilizing effect on the boundary layer, impacting gravity wave formation and downslope windstorm intensity and their impact on the flow structure in valleys downstream.
description: EGUsphere
Simulating Reflected Light Exoplanet Spectra of the Promising Direct Imaging Target, $\upsilon$ Andromedae d, with a New, Fast Sampling Method Using the Planetary Spectrum Generator
Creators: name: Saxena, Prabal
name: Villanueva, Geronimo L.
name: Zimmerman, Neil T.
name: Mandell, Avi M.
name: Smith, Adam J. R. W.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Simulations of exoplanet albedo profiles are key to planning and interpreting future direct imaging observations. In this paper we demonstrate the use of the Planetary Spectrum Generator to produce simulations of reflected light exoplanet spectra. We use PSG to examine multiple issues relevant to all models of directly imaged exoplanet spectra and to produce sample spectra of the bright, nearby exoplanet $\upsilon$ Andromedae d, a potential direct imaging target for next-generation facilities. We introduce a new, fast, and accurate subsampling technique that enables calculations of disk-integrated spectra one order of magnitude faster than Chebyshev-Gauss sampling for moderate- to high-resolution sampling. Using this method and a first-principles-derived atmosphere for $\upsilon$ And d, we simulate phase-dependent spectra for a variety of different potential atmospheric configurations. The simulated spectra for $\upsilon$ And d include versions with different haze and cloud properties. Based on our combined analysis of this planet's orbital parameters, phase-and illumination-appropriate model spectra, and realistic instrument noise parameters, we find that $\upsilon$ And d is a potentially favorable direct imaging and spectroscopy target for the Coronagraph Instrument (CGI) on the Nancy Grace Roman Space Telescope. When a noise model corresponding to the Roman CGI SPC spectroscopy mode is included, PSG predicts the time required to reach a signal-to-noise ratio of 10 of the simulated spectra in both the central wavelength bin of the Roman CGI SPC spectroscopy mode (R=50 spectrum) and of the Band 1 HLC imaging mode is approximately 400 and less than 40 hr, respectively. We also discuss potential pathways to extricating information about the planet and its atmosphere with future observations and find that Roman observations may be able to bound the interior temperature of the planet.
description: 23 pages, 14 figures
Buddying Scheme booklet
Creators: name: Sanders, Jenny
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 460105
subject: Applications in social sciences and education

description: In the School of Social Sciences a Buddying Scheme for new Postgraduate Taught International students was pilot. This was the Booklet developed for Students and Buddies as part of the SchemeFor feedback or discussion please contact jenny.sanders@ntu.ac.uk
Scale-separated AdS$_4$ vacua of IIA orientifolds and M-theory
Creators: name: Cribiori, Niccolò
name: Junghans, Daniel
name: Van Hemelryck, Vincent
name: Van Riet, Thomas
name: Wrase, Timm
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We revisit various aspects of AdS$_4$ flux vacua with scale separation in type II supergravity and M-theory. We show that massless IIA allows both weakly and strongly coupled solutions for which the classical orientifold backreaction can be tuned small. This is explicitly verified by computing the backreaction at leading order in perturbation theory. We give evidence that the strongly coupled solutions can be lifted to scale-separated and sourceless (but classically singular) geometries in 11D supergravity.
description: 43 pages
Massive young stellar objects in the Local Group irregular galaxy NGC6822 identified using machine learning
Creators: name: Kinson, David A.
name: Oliveira, Joana M.
name: van Loon, Jacco Th.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present a supervised machine learning methodology to classify stellar populations in the Local Group dwarf-irregular galaxy NGC6822. Near-IR colours (J-H, H-K, and J-K), K-band magnitudes and far-IR surface brightness (at 70 and 160 micron) measured from Spitzer and Herschel images are the features used to train a Probabilistic Random Forest (PRF) classifier. Point-sources are classified into eight target classes: young stellar objects (YSOs), oxygen- and carbon-rich asymptotic giant branch stars, red giant branch and red super-giant stars, active galactic nuclei, massive main-sequence stars and Galactic foreground stars. The PRF identifies sources with an accuracy of ~90 percent across all target classes rising to ~96 percent for YSOs. We confirm the nature of 125 out of 277 literature YSO candidates with sufficient feature information, and identify 199 new YSOs and candidates. Whilst these are mostly located in known star forming regions, we have also identified new star formation sites. These YSOs have mass estimates between ~15-50 Msun, representing the most massive YSO population in NGC 6822. Another 82 out of 277 literature candidates are definitively classified as non-YSOs by the PRF analysis. We characterise the star formation environment by comparing the spatial distribution of YSOs to those of gas and dust using archival images. We also explore the potential of using (unsupervised) t-distributed stochastic neighbour embedding maps for the identification of the same stellar population classified by the PRF.
description: 20 pages, 16 figures. Accepted for publication in MNRAS
Additional file 1 of Newborn low birth weight: do socio-economic inequality still persist in India?
Creators: name: Mishra, Prem Shankar
name: Sinha, Debashree
name: Kumar, Pradeep
name: Srivastava, Shobhit
name: Bawankule, Rahul
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Cell Biology
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Sociology
subject: FOS: Sociology
subject: Science Policy
subject: Computational Biology

description: Additional file 1: Table S1. STROBE Flow Diagram.
Buchspuren.
Creators: name: Gietkowski, Katharina Therese
Publisher: name: Humboldt-Universität zu Berlin
Year: 2021
Subjects: subject: Kunstliteratur
subject: Frühe Neuzeit
subject: Buchgeschichte
subject: 700 Künste, Bildende und angewandte Kunst

description: Durch die Betrachtung von Spuren an Büchern ist es möglich, verschiedene Funktionen von Literatur an einem Musenhof der Frühen Neuzeit zu zeigen. Welche Bedeutung Kunstliteratur am Hofe Herzog Anton Ulrichs von Braunschweig-Wolfenbüttel (1633–1714) hatte und wie der Fürst die Bücher für seine Kulturpolitik nutzte, die im Konkurrenzkampf mit Hannover um die Kurwürde eine entscheidende Rolle spielte, ist die zentrale Fragestellung innerhalb meines Dissertationsvorhabens. Das Vorhaben leistet einen Beitrag zur Erforschung von Kunstwissen in einem residenzstädtischhöfischen Kontext der Frühen Neuzeit. In diesem Aufsatz werden die Quellen und Methoden meiner Arbeit vorgestellt. Die Bücher werden hierbei zum einen als Einzelobjekte und zum anderen im Sammlungskontext der Bibliothek und der Kunstsammlung Anton Ulrichs im Schloss Salzdahlum betrachtet. Die fürstliche Hofbibliothek in Wolfenbüttel ist bis heute erhalten und somit eine wertvolle Quelle für die Forschung. Sie enthält zahlreiche Bände mit Spuren wie Besitzvermerken, Exlibris, Supralibros oder Widmungen des Auftraggebers und Kunstsammlers Herzog Anton Ulrich und mit ihm in Verbindung stehender Akteure, etwa von Familienmitgliedern und Gelehrten, aber auch von Architekten und Künstlern. Die Bücher der höfischen Bibliothek mit ihren Spuren stellen die erste Quelle dar, um Buchbesitz und Buchgebrauch aufzuzeigen. Dank zweier weiterer Quellen aus dem Bibliotheksarchiv ist es möglich, auf den Spuren Anton Ulrichs zu wandeln. Erstens dokumentiert ein Benutzerbuch, das seit 1666 geführt wurde, die Ausleihe zahlreicher Bände zur Kunstliteratur durch den Herzog. Zudem ist eine separat geführte Bücherliste erhalten, die belegt, dass Anton Ulrich sich im Jahre 1685 zahlreiche Bände der Kunstliteratur in sein Lustschloss in Salzdahlum bringen ließ, die in seinen Galerieräumen aufgestellt wurden und repräsentativen Zwecken dienten.
Argyrotaenia citrana Fernald 1889
Creators: name: Trematerra, Pasquale
name: Brown, John W.
Publisher: name: Zenodo
Year: 2004
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Tortricidae
Argyrotaenia
Argyrotaenia citrana

description: Argyrotaenia citrana (Fernald, 1889)
 Argyrotaenia citrana is known as the orange tortrix or apple skinworm in the older American economic literature. It occurs along the West Coast of North America from Canada to Mexico. We have examined specimens from British Columbia, Canada; Washington, Oregon, California, U.S.A.; and Baja California, Mexico. Freeman (1944) and Obraztsov (1961) both reported it only from the West Coast of North America. Powell (1964) stated that it is one of the most polyphagous species of North America Lepidoptera.
 Bondar (1915) reported A. citrana as attacking Citrus in Brazil, and this record probably was the source of subsequent citations of the species in South America (e.g., Essig 1926, Ebeling 1959). However, Bondar (1929) had reported this an error in identification (see Powell 1964). It is likely that this species also was misidentified by Pastrana (in litt.) based on the previous literature, and we have no direct evidence that A. citrana occurs in Argentina.
 Based on evidence from mitochondrial DNA and laboratory hybridization trials, Landry et al. (1999) concluded that A. citrana is not clearly distinct from A. franciscana. Although they did not propose the synonymy of the two, their data strongly suggest that neither species is monophyletic relative the other. Hence the two may be considered more appropriately as synonyms, with A. franciscana as the correct name based on priority.
description: Published as part of Trematerra, Pasquale & Brown, John W., 2004, Synopsis and descriptions of two new species, pp. 1-12 in Zootaxa 574 on page 8, DOI: 10.5281/zenodo.157872
Additional file 1 of Disability and self-care living strategies among adults living with HIV during the COVID-19 pandemic
Creators: name: O’Brien, Kelly K.
name: Bayoumi, Ahmed M.
name: Chan Carusone, Soo
name: Davis, Aileen M.
name: Aubry, Rachel
name: Avery, Lisa
name: Solomon, Patricia
name: Erlandson, Kristine M.
name: Bergin, Colm
name: Harding, Richard
name: Brown, Darren A.
name: Vera, Jaime H.
name: Hanna, Steven E.
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Sociology
subject: FOS: Sociology
subject: Cancer
subject: Science Policy
subject: Computational Biology

description: Additional file 1. PHQ8 (mental health) and mastery scores—pre and during the COVID-19 pandemic.
Residential development: a microspatial allocation model
Creators: name: Allan, Edward Blake
Publisher: name: University of British Columbia
Year: 2010

description: The focus of this study was the development and testing of a micro-spatial supply model which could explain and predict the allocation of residential development to subareas within a region. This involved a three step process. The first step was a review of the literature to determine what criteria were considered important in the location of residential development. Two types of location criteria were found to be important. The first of these criteria were intuitive accessibility measures used in other modelling studies. The second type of criteria were potential supply criteria suggested as important by surveys of residential developers. The second step involved the measuring and testing of various potential supply and accessibility measures to see which were important in explaining the allocation of residential development within the Greater Vancouver Regional District (GVRD). From these tests a microspatial allocation function was derived which could be tested in a large scale urban model of the GVRD. The third step involved incorporating the microspatial allocation function into the supply sub-model of a large urban model and running the model for four simulated years. The simulated data was then compared with actual data before and after the inclusion of the allocation function. Finally, the results of the tests were compared to similar studies which had compared simulated data with actual data. The test results indicate that approximately 50% of single family development and approximately 75% of multiple family development could be explained by potential supply measures. Accessibility measures were of' little significance in explaining single family development, and explained only about 10% of multiple family development. The results of testing the microspatial allocation functions in a large urban model were not as encouraging as the explanatory tests. Generally, the results of tests which compared actual data with simulated data indicate that the increase in performance with the microspatial allocation function was marginal. However, compared to similar studies the results are acceptable. In general, the study indicates that behavioural studies of the role played by developers combined with analytical models of this behaviour may provide considerable insight into the nature of the development process. It also lends strong supporting evidence to the suggestion that government organizations have been effective in allocating growth by their servicing and zoning policies.
Objektivität im Bild ermitteln.
Creators: name: Kreiseler, Sarah
Publisher: name: Humboldt-Universität zu Berlin
Year: 2021
Subjects: subject: Reproduktionsfotografie
subject: Objektivität
subject: 1900
subject: 700 Künste, Bildende und angewandte Kunst

description: Seit der Verbreitung der Fotografie ab 1839 wurde auch mit der Herstellung von Reproduktionsfotografien, die Skulpturen, kunstgewerbliche Objekte, Grafiken und Gemälde abbildeten, begonnen. Am Museum für Kunst und Gewerbe Hamburg (MK&G) dokumentierte der Fotograf Wilhelm Weimar (1857–1917) von 1897 bis 1915 auf rund 1.700 Glasplattennegativen die Sammlung von Kunstobjekten. Im Zuge einer Neubewertung des ehemaligen Arbeitsmaterials werden die Negative nun als eigenständige Foto-Objekte behandelt und weitergehend befragt. Im Rahmen des interdisziplinären Programms „Promovieren im Museum“ (PriMus) inventarisierte und digitalisierte ich diese Foto-Objekte. Eine Frage lautete, welche Umstände zum Medienwechsel – vom Zeichnen zum Fotografieren – am MK&G um 1900 führten. Der Direktor Justus Brinckmann (1843–1915) verfolgte seitdem das Ziel, „einwandfreie Dokumente“ der kunstgeschichtlichen Forschung anzubieten, wofür ihm Fotografien als geeignetes Mittel erschienen. In diesem Beitrag werden sein Meinungswechsel und die daraus resultierende Verwendung der Fotografie am MK&G untersucht. Weimars Inszenierungen und die im Bild sichtbaren Hilfsmittel geben dabei Aufschluss, wie er den Anforderungen, „einwandfreie“ und damit objektive Bilder herzustellen, gerecht zu werden versuchte. Vorgestellt werden hier die Positionierung und Mehrfachansichten eines Objekts sowie die Verwendung von Skalen. Allein die Variabilität an Mitteln und technischen Möglichkeiten der Fotografie widerlegt die Annahme, so das Fazit, dass es objektive, also vermeintliche, Abbilder geben kann. Stattdessen zeigen diese Negative Spuren des fotografischen Handwerks um 1900 auf und offenbaren den Zeitgeist, der nach Objektivität strebte.
Cosmic acceleration from string induced Galileons
Creators: name: Easson, Damien A.
name: Manton, Tucker
name: Svesko, Andrew
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: It has been shown a specific Horndeski theory of gravity arises from a consistent Kaluza-Klein reduction of the gravi-dilaton sector of the low-energy effective heterotic string action with a first $α'$ correction. Here we provide a first investigation of the cosmological solutions to the lower dimensional theory by constructing exact solutions to the field equations in various frames. At tree level, in string frame, we find the duality symmetry of the parent theory is unaltered by dimensional reduction, leading to standard bouncing and pre-Big Bang scenario solutions. For $α'\neq0$, we uncover exact models exhibiting cosmic acceleration, where we find interesting physics concerning the number of noncompact dimensions. Certain stability requirements demand the inclusion of a dilaton potential.
description: 40 pages, one figure. Comments welcome
Additional file 2 of Disability and self-care living strategies among adults living with HIV during the COVID-19 pandemic
Creators: name: O’Brien, Kelly K.
name: Bayoumi, Ahmed M.
name: Chan Carusone, Soo
name: Davis, Aileen M.
name: Aubry, Rachel
name: Avery, Lisa
name: Solomon, Patricia
name: Erlandson, Kristine M.
name: Bergin, Colm
name: Harding, Richard
name: Brown, Darren A.
name: Vera, Jaime H.
name: Hanna, Steven E.
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Sociology
subject: FOS: Sociology
subject: Cancer
subject: Science Policy
subject: Computational Biology

description: Additional file 2. Participant change in PHQ8 classification category of depression pre and during the pandemic (n = 51 participants).
Self-Bayesian Aberration Removal via Constraints for Ultracold Atom Microscopy
Creators: name: Altuntas, Emine
name: Spielman, Ian B.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: High-resolution imaging of ultracold atoms typically requires custom high numerical aperture (NA) optics, as is the case for quantum gas microscopy. These high NA objectives involve many optical elements each of which contributes to loss and light scattering, making them unsuitable for quantum back-action limited "weak" measurements. We employ a low cost high NA aspheric lens as an objective for a practical and economical-although aberrated-high resolution microscope to image ${^{87}\mathrm{Rb}}$ Bose-Einstein condensates. Here, we present a novel methodology for digitally eliminating the resulting aberrations that is applicable to a wide range of imaging strategies and requires no additional hardware. We recover nearly the full NA of our objective, thereby demonstrating a simple and powerful digital aberration correction method for achieving optimal microscopy of quantum objects. This reconstruction relies on a high quality measure of our imaging system's even-order aberrations from density-density correlations measured with differing degrees of defocus. We demonstrate our aberration compensation technique using phase contrast imaging, a dispersive imaging technique directly applicable to quantum back-action limited measurements. Furthermore, we show that our digital correction technique reduces the contribution of photon shot noise to density-density correlation measurements which would otherwise contaminate the desired quantum projection noise signal in weak measurements.
description: 18 pages, 10 figures
From TEARs to AID: the effects of emotional tears in images of refugees on helping through crowdfunding actions
Creators: name: Martinovic, Borja
name: Zickfeld, Janis
name: Bobowik, Magdalena
Publisher: name: Open Science Framework
Year: 2021
Subjects: subject: Social and Behavioral Sciences
subject: #tears #prosocialbehavior #helping #emotions #compassion #humanness #refugees #immigration

description: People are usually more willing to help those who cry. The question is why and what kind of help tears activate. The EU-funded TEARAID project will try to solve this question. It will examine the effects of tears on the promotion of two types of prosocial behaviour: autonomy- and dependency-oriented help. It will also test the role of underlying mechanisms like perceived humanness of the tearful person and self-transcendent emotions felt in response to tears, such as compassion. Photos and videos of refugees used in news stories and social campaigns by NGOs will be used to compare people’s reactions to tearful and non-tearful refugees. The findings will assist in improving measures of prosocial behaviour and creating joint initiatives with the crowdfunding industry.
Multiferroic Properties of Nanocrystalline BaTiO3
Creators: name: Mangalam, R. V. K.
name: Ray, Nirat
name: Waghmare, Umesh V.
name: Sundaresan, A.
name: Rao, C. N. R.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Some of the Multiferroics [1] form a rare class of materials that exhibit magnetoelectric coupling arising from the coexistence of ferromagnetism and ferroelectricity, with potential for many technological applications.[2,3] Over the last decade, an active research on multiferroics has resulted in the identification of a few routes that lead to multiferroicity in bulk materials.[4-6] While ferroelectricity in a classic ferroelectric such as BaTiO3 is expected to diminish with the reducing particle size,[7,8] ferromagnetism cannot occur in its bulk form.[9] Here, we use a combination of experiment and first-principles simulations to demonstrate that multiferroic nature emerges in intermediate size nanocrystalline BaTiO3, ferromagnetism arising from the oxygen vacancies at the surface and ferroelectricity from the core. A strong coupling between a surface polar phonon and spin is shown to result in a magnetocapacitance effect observed at room temperature, which can open up possibilities of new electro-magneto-mechanical devices at the nano-scale.
description: 15 pages, 5 figures
Bachelor Thesis 2016-17: Analyzing the Goal Contribution of English Club Midfielders
Creators: name: Chowdhury, Koushik
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 460502
subject: Data mining and knowledge discovery

description: Football is the most popular sport, followed by all the countries. Professional clubs spend huge amounts of money to fetch good players for competition at the highest domestic levels. In its efforts to achieve performance-related goals, clubs have to ensure that they identify the right players. In this research, a data mining technique is used to predict the goal contribution of midfielders from English football clubs, which assists the club in making player selection. With the help of five football seasons (English Clubs: 2011-12 to 2015-16) data, an attempt has been made to identify the potential of midfielders by using a classification model based on characteristics like weather, ground, competition level, timing of matches, opposition strength, substitution status, player form, and position of players. In data mining, various techniques were tested, such as BayesNet, Naive Bayes, Naive Bayes Multinomial, Logistic Regression (multinomial), Multilayer Perceptron, Random Forest, J48, and SMO. Out of these, tool SMO, which solves the quadratic programming problem related to Support Vector Machines (SVMs), gave the best result. The performances were mainly assessed with a confusion matrix that offered information about the prediction of performance by midfielders and the events that included them. In the case of this experiment, SMO was seen to be better off than other algorithms and therefore most suitable as a classifier. Thus, this work focuses on presenting the benefits of data mining approaches, with consideration given to Sequential minimal optimization (SMO) in identifying player performance and advancing the area of sports analytics studies.
Non-Hermitian Higher-Order Weyl Semimetals
Creators: name: Ghorashi, Sayed Ali Akbar
name: Li, Tianhe
name: Sato, Masatoshi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study non-Hermitian higher-order Weyl semimetals (NHHOWSMs) possessing real spectra and having inversion $\mathcal{I}$ ($\mathcal{I}$-NHHOWSM) or time-reversal symmetry $\mathcal{T}$ ($\mathcal{T}$-NHHOWSM). When the reality of bulk spectra is lost, the NHHOWSMs exhibit various configurations of surface Fermi Arcs (FAs) and Exceptional Fermi Rings (EFRs), providing a setup to investigate them on an equal footing. The EFRs only appear in the region between 2nd-order WNs. We also discover Weyl nodes originating from non-Hermicity, called non-Hermitian Weyl nodes (NHWNs). Remarkably, we find T-NHHOWSMs which host only 2nd-order NHWNs, having both surface and hinge FAs protected by the quantized biorthogonal Chern number and quadrupole moment, respectively. We call this intrinsically non-Hermitian phase exceptional HOWSM. In contrast to ordinary WNs, the NHWNs can instantly deform to line nodes, forming a monopole comet. The NHWNs also show exceptional tilt-rigidity, which is a strong resistance towards titling due to attachment to exceptional structures. This phenomenon can be a promising experimental knob. Finally, we reveal the exceptional stability of FAs called exceptional helicity. Surface FAs having opposite chirality can live on the same surface without gapping out each other due to the complex nature of the spectrum. Our work motivates an immediate experimental realization of NHHOWSMs.
description: 4 figures. arXiv admin note: text overlap with arXiv:2106.14914
Robust discovery of partial differential equations in complex situations
Creators: name: Xu, Hao
name: Zhang, Dongxiao
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: Optimization and Control (math.OC)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Data-driven discovery of partial differential equations (PDEs) has achieved considerable development in recent years. Several aspects of problems have been resolved by sparse regression-based and neural network-based methods. However, the performances of existing methods lack stability when dealing with complex situations, including sparse data with high noise, high-order derivatives and shock waves, which bring obstacles to calculating derivatives accurately. Therefore, a robust PDE discovery framework, called the robust deep learning-genetic algorithm (R-DLGA), that incorporates the physics-informed neural network (PINN), is proposed in this work. In the framework, a preliminary result of potential terms provided by the deep learning-genetic algorithm is added into the loss function of the PINN as physical constraints to improve the accuracy of derivative calculation. It assists to optimize the preliminary result and obtain the ultimately discovered PDE by eliminating the error compensation terms. The stability and accuracy of the proposed R-DLGA in several complex situations are examined for proof-and-concept, and the results prove that the proposed framework is able to calculate derivatives accurately with the optimization of PINN and possesses surprising robustness to complex situations, including sparse data with high noise, high-order derivatives, and shock waves.
description: 20 pages, 8 figures
The influence of charge detection on counting statistics
Creators: name: Braggio, Alessandro
name: Flindt, Christian
name: Novotny, Tomas
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We consider the counting statistics of electron transport through a double quantum dot with special emphasis on the dephasing induced by a nearby charge detector. The double dot is embedded in a dissipative enviroment, and the presence of electrons on the double dot is detected with a nearby quantum point contact. Charge transport through the double dot is governed by a non-Markovian generalized master equation. We describe how the cumulants of the current can be obtained for such problems, and investigate the difference between the dephasing mechanisms induced by the quantum point contact and the coupling to the external heat bath. Finally, we consider various open questions of relevance to future research.
description: 15 pages, 2 figures, Contribution to 5-th International Conference on Unsolved Problems on Noise, Lyon, France, June 2-6, 2008
Poisson structure on a space with linear SU(2) fuzziness
Creators: name: Khorrami, Mohammad
name: Fatollahi, Amir H.
name: Shariati, Ahmad
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The Poisson structure is constructed for a model in which spatial coordinates of configuration space are noncommutative and satisfy the commutation relations of a Lie algebra. The case is specialized to that of the group SU(2), for which the counterpart of the angular momentum, as well as the Euler parameterization of the phase space are introduced. SU(2)-invariant classical systems are discussed, and it is observed that the path of particle can be obtained by the solution of a first-order equation, as the case with such models on commutative spaces. The examples of free particle, rotationally-invariant potentials, and specially the isotropic harmonic oscillator are investigated in more detail.
description: 12+1 pages, no figs, LaTeX2e
Task-wise Split Gradient Boosting Trees for Multi-center Diabetes Prediction
Creators: name: Chen, Mingcheng
name: Wang, Zhenghui
name: Zhao, Zhiyun
name: Zhang, Weinan
name: Guo, Xiawei
name: Shen, Jian
name: Qu, Yanru
name: Lu, Jieli
name: Xu, Min
name: Xu, Yu
name: Wang, Tiange
name: Li, Mian
name: Tu, Wei-Wei
name: Yu, Yong
name: Bi, Yufang
name: Wang, Weiqing
name: Ning, Guang
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Diabetes prediction is an important data science application in the social healthcare domain. There exist two main challenges in the diabetes prediction task: data heterogeneity since demographic and metabolic data are of different types, data insufficiency since the number of diabetes cases in a single medical center is usually limited. To tackle the above challenges, we employ gradient boosting decision trees (GBDT) to handle data heterogeneity and introduce multi-task learning (MTL) to solve data insufficiency. To this end, Task-wise Split Gradient Boosting Trees (TSGB) is proposed for the multi-center diabetes prediction task. Specifically, we firstly introduce task gain to evaluate each task separately during tree construction, with a theoretical analysis of GBDT's learning objective. Secondly, we reveal a problem when directly applying GBDT in MTL, i.e., the negative task gain problem. Finally, we propose a novel split method for GBDT in MTL based on the task gain statistics, named task-wise split, as an alternative to standard feature-wise split to overcome the mentioned negative task gain problem. Extensive experiments on a large-scale real-world diabetes dataset and a commonly used benchmark dataset demonstrate TSGB achieves superior performance against several state-of-the-art methods. Detailed case studies further support our analysis of negative task gain problems and provide insightful findings. The proposed TSGB method has been deployed as an online diabetes risk assessment software for early diagnosis.
description: 11 pages (2 pages of supplementary), 10 figures, 7 tables. Accepted by ACM SIGKDD Conference on Knowledge Discovery and Data Mining (KDD 2021)
Monotonicity in the averaging process
Creators: name: Ben-Naim, E.
name: Krapivsky, P. L.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Probability (math.PR)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We investigate an averaging process that describes how interacting agents approach consensus through binary interactions. In each elementary step, two agents are selected at random and they reach compromise by adopting their opinion average. We show that the fraction of agents with a monotonically decreasing opinion decays as $e^{-αt}$, and that the exponent $α=\tfrac{1}{2}-\tfrac{1+\ln \ln 2}{4\ln 2}$ is selected as the extremum from a continuous spectrum of possible values. The opinion distribution of monotonic agents is asymmetric, and it becomes self-similar at large times. Furthermore, the tails of the opinion distribution are algebraic, and they are characterized by two distinct and nontrivial exponents. We also explore statistical properties of agents with an opinion strictly above average.
description: 7 pages, 7 figures
Effects of interlayer exchange on collapse mechanisms and stability of magnetic skyrmions
Creators: name: Schrautzer, Hendrik
name: von Malottki, Stephan
name: Bessarab, Pavel F.
name: Heinze, Stefan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Theoretical calculations of thermally activated decay of skyrmions in systems comprising several magnetic monolayers are presented, with a special focus on bilayer systems. Mechanisms of skyrmion collapse are identified and corresponding energy barriers and thermal collapse rates are evaluated as functions of the interlayer exchange coupling and mutual stacking of the monolayers using transition state theory and an atomistic spin Hamiltonian. In order to contrast the results to monolayer systems, the magnetic interactions within each layer are chosen so as to mimic the well-established Pd/Fe/Ir(111) system. Even bilayer systems demonstrate a rich diversity of skyrmion collapse mechanisms that sometimes co-exist. For very weakly coupled layers, the skyrmions in each layer decay successively via radially-symmetric shrinking. Slightly larger coupling leads to an asymmetric chimera collapse stabilized by interlayer exchange. When the interlayer exchange coupling reaches a certain critical value, the skyrmions collapse simultaneously. Interestingly, the overall energy barrier for the skyrmion collapse does not always converge to a multiple of that for a monolayer system in the strongly coupled regime. For a certain stacking of the magnetic layers, the energy barrier as a function of the interlayer exchange coupling features a maximum and then decreases with the coupling strength in the strong coupling regime. Calculated mechanisms of skyrmion collapse are used to ultimately predict the skyrmion lifetime. Our results reveal a comprehensive picture of thermal stability of skyrmions in magnetic multilayers and provide a perspective for realizing skyrmions with controlled properties.
description: 20 pages, 17 figures, 2 supplemental movies
Quantum magnetism and topological superconductivity in Yu-Shiba-Rusinov chains
Creators: name: Steiner, Jacob F.
name: Mora, Christophe
name: Franke, Katharina J.
name: von Oppen, Felix
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Chains of magnetic adatoms on superconductors have been discussed as promising systems for realizing Majorana end states. Here, we show that dilute Yu-Shiba-Rusinov (YSR) chains are also a versatile platform for quantum magnetism and correlated electron dynamics, with widely adjustable spin values and couplings. Focusing on subgap excitations, we derive an extended $t-J$ model for dilute quantum YSR chains and use it to study the phase diagram as well as tunneling spectra. We explore the implications of quantum magnetism for the formation of a topological superconducting phase, contrasting it to existing models assuming classical spin textures.
description: 16 pages including supplementary information; 4 figures
Bose-Einstein condensation processes with nontrivial geometric multiplicites realized via ${\cal PT}-$symmetric and exactly solvable linear-Bose-Hubbard building blocks
Creators: name: Znojil, Miloslav
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: Combinatorics (math.CO)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: It is well known that using the conventional non-Hermitian but ${\cal PT}-$symmetric Bose-Hubbard Hamiltonian with real spectrum one can realize the Bose-Einstein condensation (BEC) process in an exceptional-point limit of order $N$. Such an exactly solvable simulation of the BEC-type phase transition is, unfortunately, incomplete because the standard version of the model only offers an extreme form of the limit characterized by a minimal geometric multiplicity $K=1$. In our paper we describe a rescaled and partitioned direct-sum modification of the linear version of the Bose-Hubbard model which remains exactly solvable while admitting any value of $K\geq 1$. It offers a complete menu of benchmark models numbered by a specific combinatorial scheme. In this manner, an exhaustive classification of the general BEC patterns with any geometric multiplicity is obtained and realized in terms of an exactly solvable generalized Bose-Hubbard model.
description: 26 pp., 3 figures
Ferroelectric Polarization Reversal vs Pump Spot Shape
Creators: name: Abalmasov, Veniamin A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: It has recently been shown that the polarization of a ferroelectric can be strongly affected by light pumping or even transiently reversed by mid-IR pumping within a record short subpicosecond timescale. It was then suggested that the reversal of polarization is most likely prevented by the depolarizing field that appears during the process. To minimize the effect of the depolarizing field, I propose to create an elongated domain by choosing a corresponding pump spot shape. I calculate the polarization dynamics for a particular experimental setup with mid-IR pumping and show that the polarization reversal is possible in this case.
description: 4 pages, 3 figures
The impact of the new measurement of the $\rm ^{12}C+^{12}C$ fusion cross section on the final compactness of the massive stars
Creators: name: Chieffi, Alessandro
name: Roberti, Lorenzo
name: Limongi, Marco
name: La Cognata, Marco
name: Lamia, Livio
name: Palmerini, Sara
name: Pizzone, Rosario Gianluca
name: Sparta', Roberta
name: Tumino, Aurora
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We discuss how the new measurement of the $^{12}C+^{12}C$ fusion cross section carried out with the Trojan Horse Method (Tumino, A., Spitaleri, C., La Cognata, M., et al., 2018, Nature 57, 687) affects the compactness of a star, i.e. basically the binding energy of the inner mantle, at the onset of the core collapse. In particular, we find that this new cross section significantly changes the dependence of the compactness on the initial mass with respect to previous findings obtained in Chieffi & Limongi 2020 (ApJ 890, 43) by adopting the classical cross section provided by Caughlan, G.R., and Fowler, W.D. 1988 (At. Data Nucl. Data Tables 40, 283). A non monotonic but well defined behavior is confirmed also in this case and no scatter of the compactness around the main trend is found. Such an occurrence could impact the possible explodability of the stars.