cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Spectral Evolution of Ultraluminous X-ray Pulsar NGC 300 ULX-1
Creators: name: Ng, Mason
name: Remillard, Ronald A.
name: Steiner, James F.
name: Chakrabarty, Deepto
name: Pasham, Dheeraj R.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We report on results from a one-year soft X-ray observing campaign of the ultraluminous X-ray pulsar NGC 300 ULX-1 by the Neutron star Interior Composition Explorer (NICER) during 2018--2019. Our analysis also made use of data from Swift/XRT and XMM-Newton in order to model and remove contamination from the nearby eclipsing X-ray binary NGC 300 X-1. We constructed and fitted a series of 5-day averaged NICER spectra of NGC 300 ULX-1 in the 0.4--4.0 keV range to evaluate the long-term spectral evolution of the source, and found that an absorbed power-law model provided the best fit overall. Over the course of our observations, the source flux (0.4--4.0 keV; absorbed) dimmed from $2\times10^{-12}$ to below $10^{-13}{\rm\,erg\,s^{-1}\,cm^{-2}}$ and the spectrum softened, with the photon index going from $Γ\approx1.6$ to $Γ\approx2.6$. We interpret the spectral softening as reprocessed emission from the accretion disk edge coming into view while the pulsar was obscured by the possibly precessing disk. Some spectral fits were significantly improved by the inclusion of a disk blackbody component, and we surmise that this could be due to the pulsar emerging in between obscuration episodes by partial covering absorbers. We posit that we observed a low-flux state of the system (due to line-of-sight absorption) punctuated by the occasional appearance of the pulsar, indicating short-term source variability nested in longer-term accretion disk precession timescales.
description: 13 pages, including 7 figures and 2 tables. Accepted for publication in the Astrophysical Journal
Spital und Bad des Legionslagers Vindobona. Die Archäologischen Ergebnisse der Kanalgrabung Wien I., Salvatorgasse (1951)
Creators: name: Neumann, Alfred
Publisher: name: Verlag des Römisch-Germanischen Zentralmuseums Mainz
Year: 2017
Subjects: Römerzeit; Mitteleuropa; Österreich; Wien; Militäranlagen; Ziegelstempel; Grabfunde; Langobarden; Anthropologie

description: [nicht vorhanden / not available]
description: Jahrbuch des Römisch-Germanischen Zentralmuseums Mainz, Bd. 12 (1965)
Fluctuation Analysis for the Loss From Default
Creators: name: Spiliopoulos, Konstantinos
name: Sirignano, Justin A.
name: Giesecke, Kay
Publisher: name: arXiv
Year: 2013
Subjects: subject: Probability (math.PR)
subject: Portfolio Management (q-fin.PM)
subject: Risk Management (q-fin.RM)
subject: FOS: Mathematics
subject: FOS: Economics and business
subject: 60F05, 60F17, 60G55

description: We analyze the fluctuation of the loss from default around its large portfolio limit in a class of reduced-form models of correlated firm-by-firm default timing. We prove a weak convergence result for the fluctuation process and use it for developing a conditionally Gaussian approximation to the loss distribution. Numerical results illustrate the accuracy and computational efficiency of the approximation.
Simple and Fast Group Robustness by Automatic Feature Reweighting
Creators: name: Qiu, Shikai
name: Potapczynski, Andres
name: Izmailov, Pavel
name: Wilson, Andrew Gordon
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: A major challenge to out-of-distribution generalization is reliance on spurious features -- patterns that are predictive of the class label in the training data distribution, but not causally related to the target. Standard methods for reducing the reliance on spurious features typically assume that we know what the spurious feature is, which is rarely true in the real world. Methods that attempt to alleviate this limitation are complex, hard to tune, and lead to a significant computational overhead compared to standard training. In this paper, we propose Automatic Feature Reweighting (AFR), an extremely simple and fast method for updating the model to reduce the reliance on spurious features. AFR retrains the last layer of a standard ERM-trained base model with a weighted loss that emphasizes the examples where the ERM model predicts poorly, automatically upweighting the minority group without group labels. With this simple procedure, we improve upon the best reported results among competing methods trained without spurious attributes on several vision and natural language classification benchmarks, using only a fraction of their compute.
description: ICML 23. Code available at https://github.com/AndPotap/afr
Beware the Trolley Zealots
Creators: name: Eyal, Gil
Publisher: name: Columbia University
Year: 2020
Subjects: subject: Sociology
subject: FOS: Sociology
subject: Utilitarianism
subject: Bioethics
subject: COVID-19 (Disease)--Social aspects

description: This essay draws on Mary Douglas’ theory of institutional styles of thinking to analyze the debate about how and when the Coronavirus crisis can be brought to an end. The dominant approach, I show, frames the problem in utilitarian terms, akin to what is known among philosophers as “the trolley problem.” I point out the pitfalls of this framing and contrast it with a counter-frame taken from the Judeo-Christian tradition of pastoral leadership. The lacunae of this institutional style of thinking are pointed out as well, in order to develop the critical distance necessary for a reasoned intervention in the crisis.
Floquet Engineering of Nonequilibrium Valley-Polarized Quantum Anomalous Hall Effect with Tunable Chern Number
Creators: name: Zhan, Fangyang
name: Zeng, Junjie
name: Chen, Zhuo
name: Jin, Xin
name: Fan, Jing
name: Chen, Tingyong
name: Wang, Rui
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Numerous attempts have been made so far to explore the quantum anomalous Hall effect (QAHE), but the ultralow observed temperature strongly hinders its practical applications. Hence, it is of great interest to go beyond the existing paradigm of QAHE. Here, we propose that Floquet engineering offers a strategy to realize the QAHE via hybridization of Floquet-Bloch bands. Based on first-principles calculations and Floquet theorem, we unveil that nonequilibrium valley-polarized QAHE (VP-QAHE), independent of magnetic orders, is widely present in ferromagnetic and nonmagnetic members of two-dimensional family materials $M$Si$_2$$Z_4$ ($M$ = Mo, W, V; $Z$ = N, P, As) by irradiating circularly polarized light (CPL). Remarkably, by tuning the frequency, intensity, and handedness of incident CPL, the Chern number of VP-QAHE is highly tunable and up to $\mathcal{C}=\pm 4$. We reveal that such Chern number tunable VP-QAHE attributes to light-induced trigonal warping and multiple band inversion at different valleys. The valley-resolved chiral edge states and quantized plateau of Hall conductance, which facilitates the experimental measurement, are visible inside the global band gap. Our work not only establishes Floquet Engineering of nonequilibrium VP-QAHE with tunable Chern number in realistic materials, but also provides a promising avenue to explore emergent topological phases under light irradiation.
description: 6 pages, 4 figures
Anthropologischer Befund von S1-S4
Creators: name: Pacher, Helga-Maria
Publisher: name: Verlag des Römisch-Germanischen Zentralmuseums Mainz
Year: 2017
Subjects: Römerzeit; Mitteleuropa; Österreich; Wien; Militäranlagen; Ziegelstempel; Grabfunde; Langobarden; Anthropologie

description: [nicht vorhanden / not available]
description: Jahrbuch des Römisch-Germanischen Zentralmuseums Mainz, Bd. 12 (1965)
On the sphericity test with large-dimensional observations
Creators: name: Wang, Qinwen
name: Yao, Jianfeng
Publisher: name: arXiv
Year: 2013
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics

description: In this paper, we propose corrections to the likelihood ratio test and John's test for sphericity in large-dimensions. New formulas for the limiting parameters in the CLT for linear spectral statistics of sample covariance matrices with general fourth moments are first established. Using these formulas, we derive the asymptotic distribution of the two proposed test statistics under the null. These asymptotics are valid for general population, i.e. not necessarily Gaussian, provided a finite fourth-moment. Extensive Monte-Carlo experiments are conducted to assess the quality of these tests with a comparison to several existing methods from the literature. Moreover, we also obtain their asymptotic power functions under the alternative of a spiked population model as a specific alternative.
description: 37 pages, 3 figures
Witnessing non-Markovianity by Quantum Quasi-Probability Distributions
Creators: name: Richter, Moritz F.
name: Wiedenmann, Raphael
name: Breuer, Heinz-Peter
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We employ frames consisting of rank-one projectors (i.e. pure quantum states) and their induced informationally complete quantum measurements (IC-POVMs) to represent generally mixed quantum states by quasi-probability distributions. In the case of discrete frames on finite dimensional systems this results in a vector like representation by quasi-probability vectors, while for the continuous frame of coherent states in continuous variable (CV) systems the approach directly leads to the celebrated representation by Glauber-Sudarshan P-functions and Husimi Q-functions. We explain that the Kolmogorov distances between these quasi-probability distributions lead to upper and lower bounds of the trace distance which measures the distinguishability of quantum states. We apply these results to the dynamics of open quantum systems and construct a non-Markovianity witness based on the Kolmogorov distance of the P- and Q-functions. By means of several examples we discuss the performance of this witness and demonstrate that it is useful in the regime of high entropy states for which a direct evaluation of the trace distance is typically very demanding. For Gaussian dynamics in CV systems we even find a suitable non-Markovianity measure based on the Kolmogorov distance between the P-functions which can alternatively be used as a witness for non-Gaussianity.
Stability studies of first order spin-hydrodynamic frameworks
Creators: name: Daher, Asaad
name: Das, Arpan
name: Ryblewski, Radoslaw
Publisher: name: arXiv
Year: 2022
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study the stability of first-order dissipative spin-hydrodynamic frameworks. We considered two different first-order dissipative spin-hydrodynamic frameworks. The first one considers the spin chemical potential ($ω^{αβ}$) to be first order ($\mathcal{O}(\partial)$) in the hydrodynamic gradient expansion. The hydrodynamic gradient ordering of the spin chemical potential is a debatable issue within the frameworks of spin hydrodynamics. Therefore as a second choice, we also consider the spin hydrodynamic equations with $ω^{αβ}\sim\mathcal{O}(1)$. We find that for both frameworks, at the level of linear perturbations some spin modes can be unstable. To remove these generic instabilities we consider the Frenkel condition. We argue that Frenkel condition helps get rid of the unstable solutions in both cases, but with a physical drawback for the case where $ω^{μν}\sim\mathcal{O}(\partial)$.
description: 11 pages. No figures. Comments are welcome
Additional file 1 of Trends in Israeli community-based opioid prescribing, 2010–2020, an observational study of the country’s largest HMO
Creators: name: Dressler, Reuven L.
name: Kaliner, Ehud
name: Cohen, Matan J.
Publisher: name: figshare
Year: 2023
Subjects: subject: Medicine
subject: Pharmacology
subject: Biotechnology
subject: Ecology
subject: FOS: Biological sciences
subject: Biological Sciences not elsewhere classified
subject: Cancer
subject: Science Policy
subject: Mental Health

description: Additional file 1: Supplementary Table.
Kähler currents and null loci
Creators: name: Collins, Tristan C.
name: Tosatti, Valentino
Publisher: name: arXiv
Year: 2013
Subjects: subject: Complex Variables (math.CV)
subject: Algebraic Geometry (math.AG)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 32Q15, 53C55, 32U05, 32U25, 14E15, 14C20

description: We prove that the non-Kahler locus of a nef and big class on a compact complex manifold bimeromorphic to a Kahler manifold equals its null locus. In particular this gives an analytic proof of a theorem of Nakamaye and Ein-Lazarsfeld-Mustata-Nakamaye-Popa. As an application, we show that finite time non-collapsing singularities of the Kahler-Ricci flow on compact Kahler manifolds always form along analytic subvarieties, thus answering a question of Feldman-Ilmanen-Knopf and Campana. We also extend the second author's results about noncollapsing degenerations of Ricci-flat Kahler metrics on Calabi-Yau manifolds to the nonalgebraic case.
description: 29 pages, 1 figure; small improvements, final version to appear in Invent. Math
Thermodynamics of the Ising model encoded in restricted Boltzmann machines
Creators: name: Gu, Jing
name: Zhang, Kai
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: The restricted Boltzmann machine (RBM) is a two-layer energy-based model that uses its hidden-visible connections to learn the underlying distribution of visible units, whose interactions are often complicated by high-order correlations. Previous studies on the Ising model of small system sizes have shown that RBMs are able to accurately learn the Boltzmann distribution and reconstruct thermal quantities at temperatures away from the critical point $T_c$. How the RBM encodes the Boltzmann distribution and captures the phase transition are, however, not well explained. In this work, we perform RBM learning of the $2d$ and $3d$ Ising model and carefully examine how the RBM extracts useful probabilistic and physical information from Ising configurations. We find several indicators derived from the weight matrix that could characterize the Ising phase transition. We verify that the hidden encoding of a visible state tends to have an equal number of positive and negative units, whose sequence is randomly assigned during training and can be inferred by analyzing the weight matrix. We also explore the physical meaning of visible energy and loss function (pseudo-likelihood) of the RBM and show that they could be harnessed to predict the critical point or estimate physical quantities such as entropy.
description: 13 pages, 8 figures
Dendrochronologische Untersuchung eines alamannischen Baumsarges von Oberflacht im RGZM
Creators: name: Hollstein, Ernst
Publisher: name: Verlag des Römisch-Germanischen Zentralmuseums Mainz
Year: 2017
Subjects: Frühmittelalter; 6. Jh. n.Chr.; Deutschland; Nordrhein-Westfalen; Morken; Grabfunde; Dendrochronologie

description: [nicht vorhanden / not available]
description: Jahrbuch des Römisch-Germanischen Zentralmuseums Mainz, Bd. 12 (1965)
Magnetically-activated accretion outbursts of pre-main sequence discs
Creators: name: Cleaver, Jacob
name: Hartmann, Lee
name: Bae, Jaehan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We investigate whether triggering of the magnetorotational instability (MRI) in protoplanetary discs can account for the wide diversity of observed accretion outbursts. We show that short-lived, relatively low accretion rate events probably result from triggering in the inner disc and can occur at low surface densities, comparable to or smaller than the minimum mass solar nebula, and thus are very unlikely to result from MRI triggering by gravitational instability. We develop time-dependent accretion disc models using an $α$-viscosity approach and calculate light curves to compare with observations. Our modeling indicates that the lag time between infrared and optical bursts seen in Gaia 17bpi can be explained with an outside-in propagation with an $α\sim 0.1$ in the MRI-active region, consistent with other estimates. While outbursts in inner discs can show time delays of a few years between infrared and optical light curves, our models indicate that large, FU Ori-like bursts can exhibit infrared precursors decades before optical bursts. Detecting such precursors could enable analysis of the central star before it is overwhelmed by the rapid accreting material, as well as constraining outburst physics. Our results emphasize the importance of near-infrared monitoring of young stellar objects in addition to optical surveys. In addition, our findings emphasize the need for more sophisticated, three-dimensional, non-ideal magnetohydrodynamic simulations to fully exploit observational results.
description: 13 pages, 20 figures, accepted by MNRAS
Pre-emergence Signatures Of Horizontal Divergent Flows In Solar Active Regions
Creators: name: Rees-Crockford, T.
name: Nelson, C. J.
name: Mathioudakis, M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Solar active regions (ARs) play a fundamental role in driving many of the geo-effective eruptions which propagate into the Solar System. However, we are still unable to consistently predict where and when ARs will occur across the solar disk by identifying pre-emergence signatures in observables such as the Doppler velocity (without using Helioseismic methods). Here we aim to determine the earliest time at which pre-emergence signatures, specifically the Horizontal Divergent Flow (HDF), can be confidently detected using data from the Solar Dynamics Observatory's Helioseismic and Magnetic Imager (SDO/HMI). Initially, we follow previous studies using the thresholding method, which searches for significant increases in the number of pixels that display a specific line-of-sight velocity. We expand this method to more velocity windows and conduct a basic parameter study investigating the effect of cadence on the inferred results. Our findings agree with previous studies with $37.5$% of ARs displaying a HDF, with average lead times between the HDF and flux emergence of $58$ minutes. We present a new potential signature of flux emergence which manifests as cadence-independent transient disruptions to the amplitudes of multiple velocity windows and recover potential pre-emergence signatures for 10 of the 16 ARs studied, with lead times of 60-156 minutes. Several effects can influence both the estimated times of both HDF and flux emergence suggesting that one may need to combine Doppler and magnetic field data to get a reliable indicator of continued flux emergence.
description: 19 Pages, 8 Figures, 2 Tables, 2 Supplemental Figure Sets
Radio source-component association for the LOFAR Two-metre Sky Survey with region-based convolutional neural networks
Creators: name: Mostert, Rafaël I. J.
name: Duncan, Kenneth J.
name: Alegre, Lara
name: Röttgering, Huub J. A.
name: Williams, Wendy L.
name: Best, Philip N.
name: Hardcastle, Martin J.
name: Morganti, Raffaella
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Radio loud active galactic nuclei (RLAGNs) are often morphologically complex objects that can consist of multiple, spatially separated, components. Astronomers often rely on visual inspection to resolve radio component association. However, applying visual inspection to all the hundreds of thousands of well-resolved RLAGNs that appear in the images from the Low Frequency Array (LOFAR) Two-metre Sky Survey (LoTSS) at $144$ MHz, is a daunting, time-consuming process, even with extensive manpower. Using a machine learning approach, we aim to automate the radio component association of large ($> 15$ arcsec) radio components. We turned the association problem into a classification problem and trained an adapted Fast region-based convolutional neural network to mimic the expert annotations from the first LoTSS data release. We implemented a rotation data augmentation to reduce overfitting and simplify the component association by removing unresolved radio sources that are likely unrelated to the large and bright radio components that we consider using predictions from an existing gradient boosting classifier. For large ($> 15$ arcsec) and bright ($> 10$ mJy) radio components in the LoTSS first data release, our model provides the same associations for $85.3\%\pm0.6$ of the cases as those derived when astronomers perform the association manually. When the association is done through public crowd-sourced efforts, a result similar to that of our model is attained. Our method is able to efficiently carry out manual radio-component association for huge radio surveys and can serve as a basis for either automated radio morphology classification or automated optical host identification. This opens up an avenue to study the completeness and reliability of samples of radio sources with extended, complex morphologies.
description: 22 pages; accepted for publication in A&A
Microwave-assisted switching of a nanomagnet: analytical determination of the optimal microwave field
Creators: name: Barros, N.
name: Rassam, M.
name: Kachkachi, H.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We analytically determine the optimal microwave field that allows for the magnetization reversal of a nanomagnet modeled as a macrospin. This is done by minimizing the total injected energy. The results are in good agreement with the fields obtained numerically using the optimal control theory. For typical values of the damping parameter, a weak microwave field is sufficient to induce switching through a resonant process. The optimal field is orthogonal to the magnetization direction at any time and modulated both in amplitude and frequency. The dependence of the pulse shape on the applied field and damping parameter is interpreted. The total injected energy is found to be proportionnal to the energy barrier between the initial state and the saddle point and to the damping parameter. This result may be used as a means for probing the damping parameter in real nanoparticles.
All-carbon nanotube solar cell devices mimic photosynthesis
Creators: name: Oyibo, Gideon
name: Barrett, Thomas
name: Jois, Sharadh
name: Blackburn, Jeffrey
name: Lee, Ji Ung
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Photovoltaics has two main processes: Optical absorption and power conversion. In photosynthesis, the two equivalent processes are optical absorption and chemical conversion. Whereas in the latter, the two processes are carried out by distinct proteins, in conventional photovoltaic diodes, the two processes are convoluted because the optical and transport paths are the same, leading to inefficiencies. Here, we separate the site and direction of light absorption from those of power generation to show that semiconducting single-walled carbon nanotubes (s-SWCNTs) provide an artificial system that models photosynthesis in a tandem geometry. Using different s-SWCNT chiralities, we implement an energy funnel in dual-gated p-n diodes. This enables the capture of photons from multiple regions of the solar spectrum and the funneling of photogenerated excitons to the smallest bandgap s-SWCNT layer, where they become free carriers. As a result, we demonstrate an increase in the magnitude and spectral response of photocurrent by adding more s-SWCNT layers of different bandgaps without a corresponding deleterious increase in the dark leakage current.
Indonesia: Downstream linkages
Creators: name: Maennling, Nicolas Wolfram
name: Toledano, Perrine
Publisher: name: Columbia University
Year: 2018
Subjects: Sustainable development
Commercial policy
Exports--Government policy
Mines and mineral resources
Ore-dressing

description: Indonesia is the largest exporter of nickel ore and tin in the world and ranks among the biggest for copper and gold production. To add value to these minerals, Indonesia imposed an export ban which has recently been relaxed due to private sector pushback and falling revenues. While the short-term costs of the ban are apparent, the long-term impacts remain unclear. The Indonesia case study highlights the need to target downstream policies by sector and the shortcomings of blanket regulations. For nickel and copper, where Indonesia boasts world-class reserves, companies have largely remained and are more likely to build processing facilities. Indonesia’s weaker position in bauxite has meant that a lot of operations have shut down and investors have left due to the export ban.
Attention Regularized Laplace Graph for Domain Adaptation
Creators: name: Luo, Lingkun
name: Chen, Liming
name: Hu, Shiqiang
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: In leveraging manifold learning in domain adaptation (DA), graph embedding-based DA methods have shown their effectiveness in preserving data manifold through the Laplace graph. However, current graph embedding DA methods suffer from two issues: 1). they are only concerned with preservation of the underlying data structures in the embedding and ignore sub-domain adaptation, which requires taking into account intra-class similarity and inter-class dissimilarity, thereby leading to negative transfer; 2). manifold learning is proposed across different feature/label spaces separately, thereby hindering unified comprehensive manifold learning. In this paper, starting from our previous DGA-DA, we propose a novel DA method, namely Attention Regularized Laplace Graph-based Domain Adaptation (ARG-DA), to remedy the aforementioned issues. Specifically, by weighting the importance across different sub-domain adaptation tasks, we propose the Attention Regularized Laplace Graph for class-aware DA, thereby generating the attention regularized DA. Furthermore, using a specifically designed FEEL strategy, our approach dynamically unifies alignment of the manifold structures across different feature/label spaces, thus leading to comprehensive manifold learning. Comprehensive experiments are carried out to verify the effectiveness of the proposed DA method, which consistently outperforms the state-of-the-art DA methods on 7 standard DA benchmarks, i.e., 37 cross-domain image classification tasks including object, face, and digit images. An in-depth analysis of the proposed DA method is also discussed, including sensitivity, convergence, and robustness.
description: 18 pages, 19 figures, This work is accepted by IEEE Transactions on Image Processing and will be available online soon. arXiv admin note: text overlap with arXiv:2101.04563
Compact spectrometer based on disordered multi-mode interferometer
Creators: name: Poudel, Ankit
name: Bhattarai, Pravin
name: Maharjan, Rijan
name: Curry, Richard J
name: Crowe, Iain F
name: Dhakal, Ashim
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We demonstrate a compact (40 $μ$m $\times$ 260 $μ$m) spectrometer based on multimode interference aided by scattering of light from random SiO$_2$-filled hole arrays on a silicon-on-insulator platform. We characterize the performance of the spectrometer for wavelengths around 1310 nm, and report that the spectrometer can reconstruct a broadband $\sim$ 67 nm source, as well as Lorentzian probes of $\sim$ 1 nm bandwidth. This compact nanometer level resolution spectrometer can be fabricated at a low cost for lab-on-a-chip sensing and imaging applications.
description: 11 pages, 6 figures
Additional file 1 of Superior sagittal sinus thrombosis in the course of mixed phenotype acute leukaemia treated with acute lymphoblastic leukaemia-like therapy—a case report
Creators: name: Lizurej, Wojciech
name: Mazurkiewicz, Łukasz
name: Kowalski, Michał
name: Szydłowska, Sylwia
name: Wyrzykowski, Michał
name: Lewandowski, Krzysztof
Publisher: name: figshare
Year: 2023
Subjects: subject: Medicine
subject: Cell Biology
subject: Physiology
subject: FOS: Biological sciences
subject: Pharmacology
subject: Cancer
subject: Hematology
subject: Infectious Diseases
subject: FOS: Health sciences

description: Supplementary Material 1
Multi-wavelength Observations of the Giant X-ray Flare Galaxy NGC 5905: signatures of tidal disruption
Creators: name: Raichur, H.
name: Das, M.
name: Herrero, A. Alonso
name: Shastri, P.
name: Kantharia, N. G.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: NGC 5905 is one of the few galaxies with no prior evidence for an AGN in which an X-ray flare, due to the tidal disruption of a star by the massive black hole in the center of the galaxy, was detected by the RASS in 1990-91. Here we present analysis of late-time follow-up observations of NGC 5905 using Chandra, Spitzer VLA 3 GHz and 8 GHz archival data and GMRT 1.28 GHz radio observations. The X-ray image shows no compact source that could be associated with an AGN. Instead, the emission is extended -- likely due to nuclear star formation and the total measured X-ray luminosity is comparable to the X-ray luminosity determined from the 2002 Chandra observations. Diffuse X-ray emission was detected close to the circum-nuclear star forming ring. The Spitzer 2006 mid-infrared spectrum also shows strong evidence of nuclear star formation but no clear AGN signatures. The semi-analytical models of Tommasin et. al. 2010 together with the measured [OIV]/[NeII] line ratio suggest that at most only 5.6% of the total IR Flux at 19 $μ$m is being contributed by the AGN. The GMRT 1.28 GHz observations reveal a nuclear source. In the much higher resolution VLA 3 GHz map, the emission has a double lobed structure of size 2.7'' due to the circumnuclear star forming ring. The GMRT 1.28 GHz peak emission coincides with the center of the circumnuclear ring. We did not detect any emission in the VLA 8 GHz (1996) archival data. The 3 $σ$ upper limits for the radio afterglow of the TDE at 1.28 GHz, 3 GHz and 8 GHz are 0.17 mJy, 0.09 mJy and 0.09 mJy, respectively. Our studies thus show that (i) NGC 5905 has a declining X-ray flux consistent with a TDE, (ii) the IR flux is dominated by nuclear star formation, (iii) the nuclear radio emission observed from the galaxy is due to circumnuclear star formation, (iv) no compact radio emission associated with a radio afterglow from the TDE is detected.
description: 12 pages, 8 figures, accepted to be published in Astrophysics and Space Science
On the Rényi index of random graphs
Creators: name: Yuan, Mingao
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics

description: Networks (graphs) permeate scientific fields such as biology, social science, economics, etc. Empirical studies have shown that real-world networks are often heterogeneous, that is, the degrees of nodes do not concentrate on a number. Recently, the Rényi index was tentatively used to measure network heterogeneity. However, the validity of the Rényi index in network settings is not theoretically justified. In this paper, we study this problem. We derive the limit of the Rényi index of a heterogeneous Erdös-Rényi random graph and a power-law random graph, as well as the convergence rates. Our results show that the Erdös-Rényi random graph has asymptotic Rényi index zero and the power-law random graph (highly heterogeneous) has asymptotic Rényi index one. In addition, the limit of the Rényi index increases as the graph gets more heterogeneous. These results theoretically justify the Rényi index is a reasonable statistical measure of network heterogeneity. We also evaluate the finite-sample performance of the Rényi index by simulation.
Preparations for Quantum Simulations of Quantum Chromodynamics in 1+1 Dimensions: (II) Single-Baryon $β$-Decay in Real Time
Creators: name: Farrell, Roland C.
name: Chernyshev, Ivan A.
name: Powell, Sarah J. M.
name: Zemlevskiy, Nikita A.
name: Illa, Marc
name: Savage, Martin J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A framework for quantum simulations of real-time weak decays of hadrons and nuclei in a 2-flavor lattice theory in one spatial dimension is presented. A single generation of the Standard Model is found to require 16 qubits per spatial lattice site after mapping to spin operators via the Jordan-Wigner transformation. Both quantum chromodynamics and flavor-changing weak interactions are included in the dynamics, the latter through four-Fermi effective operators. Quantum circuits which implement time evolution in this lattice theory are developed and run on Quantinuum's H1-1 20-qubit trapped ion system to simulate the $β$-decay of a single baryon on one lattice site. These simulations include the initial state preparation and are performed for both one and two Trotter time steps. The potential intrinsic error-correction properties of this type of lattice theory are discussed and the leading lattice Hamiltonian required to simulate $0νββ$-decay of nuclei induced by a neutrino Majorana mass term is provided.
description: 27 pages, 11 figures. Typo fixed in v3
Disordered Systems Insights on Computational Hardness
Creators: name: Gamarnik, David
name: Moore, Cristopher
name: Zdeborová, Lenka
Publisher: name: arXiv
Year: 2022
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Computational Complexity (cs.CC)
subject: Probability (math.PR)
subject: Statistics Theory (math.ST)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: In this review article, we discuss connections between the physics of disordered systems, phase transitions in inference problems, and computational hardness. We introduce two models representing the behavior of glassy systems, the spiked tensor model and the generalized linear model. We discuss the random (non-planted) versions of these problems as prototypical optimization problems, as well as the planted versions (with a hidden solution) as prototypical problems in statistical inference and learning. Based on ideas from physics, many of these problems have transitions where they are believed to jump from easy (solvable in polynomial time) to hard (requiring exponential time). We discuss several emerging ideas in theoretical computer science and statistics that provide rigorous evidence for hardness by proving that large classes of algorithms fail in the conjectured hard regime. This includes the overlap gap property, a particular mathematization of clustering or dynamical symmetry-breaking, which can be used to show that many algorithms that are local or robust to changes in their input fail. We also discuss the sum-of-squares hierarchy, which places bounds on proofs or algorithms that use low-degree polynomials such as standard spectral methods and semidefinite relaxations, including the Sherrington-Kirkpatrick model. Throughout the manuscript, we present connections to the physics of disordered systems and associated replica symmetry breaking properties.
description: 42 pages
Schriftenverzeichnis Otto Kunkel
Creators: name: Redaktion, Die
Publisher: name: Verlag des Römisch-Germanischen Zentralmuseums Mainz
Year: 2017

description: [nicht vorhanden / not available]
description: Jahrbuch des Römisch-Germanischen Zentralmuseums Mainz, Bd. 13 (1966)
Ein Kammhelm aus dem oberen Maintal
Creators: name: Pescheck, Christian
Publisher: name: Verlag des Römisch-Germanischen Zentralmuseums Mainz
Year: 2017
Subjects: Bronzezeit; Urnenfelderzeit; Deutschland; Bayern; Ebing;Depotfund; Helme; Bronzewaffen

description: [nicht vorhanden / not available]
description: Jahrbuch des Römisch-Germanischen Zentralmuseums Mainz, Bd. 13 (1966)
Phase Transition of Random Non-Uniform Hypergraphs
Creators: name: de Panafieu, Elie
Publisher: name: arXiv
Year: 2013
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: Non-uniform hypergraphs appear in various domains of computer science as in the satisfiability problems and in data analysis. We analyse a general model where the probability for an edge of size $t$ to belong to the hypergraph depends of a parameter $ω_t$ of the model. It is a natural generalization of the models of graphs presented in "The first cycles in an evolving graph" [Flajolet, Knuth, Pittel, 1989] and in the "Birth of the giant component" [Janson, Knuth, Łuczak, Pittel, 1993]. The present paper follows the same general approach based on analytic combinatorics. We show that many analytic tools developed for the analysis of graphs can be extended surprisingly well to non-uniform hypergraphs. Specifically, we investigate random hypergraphs with a large number of vertices $n$ and a complexity, defined as the "excess", proportional to $n$. We analyze their typical structure before, near and after the birth of the "complex" components, that are the connected components with more than one cycle. Finally, we compute statistics of the model to link number of edges and excess.
description: 29 pages, 6 figures
He-star donor AM CVn stars and their progenitors as LISA sources
Creators: name: Liu, Wei-Min
name: Yungelson, Lev
name: Kuranov, Alexandre
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Ultracompact cataclysmic variables (CVs) of the AM CVn type are deemed to be important verification sources for the future space gravitational wave detectors such as the Laser Interferometer Space Antenna (LISA). We model the present-day Galactic population of AM CVn stars with He-star donors. Such a population has long expected to exist, though only a couple of candidates are known. We applied the hybrid method of binary population synthesis (BPS) which combines a simulation of the population of immediate precursors of AM CVn stars by a fast BPS code with subsequent tracking of their evolution by a full evolutionary code. The model predicts that the present birthrate of He-donor AM CVn stars in the Galaxy is $4.6\times 10^{-4}$ per yr and the Galaxy may harbour about 112000 objects of this class which have orbital periods less than 42-43 min. The foreground confusion limit and instrumental noise of LISA prevent the discovery of longer periods systems in gravitational waves. We find that about 500 He-star AM CVns may be detected by LISA with signal-to-noise ratio (S/N)>5 during a 4 yr mission. Within 1 Kpc from the Sun, there may exist up to 130 He-star AM CVns with the periods in the same range, which may serve as verification binaries, if detected in the electromagnetic spectrum. In the Milky Way, there are also about 14800 immediate precursors of AM CVn stars. They are detached systems with a stripped low-mass He-star and a white dwarf companion, out of which about 75 may potentially be observed by LISA during its mission.
description: 9 pages, 4 figures, accepted by Astronomy and Astrophysics
Molecular-Beam Spectroscopy with an Infinite Interferometer: Spectroscopic Resolution and Accuracy
Creators: name: Schultz, Thomas
name: Heo, In
name: Lee, Jong Chan
name: Özer, Begüm Rukiye
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: An interferometer with effectively infinite maximum optical path difference removes the dominant resolution limitation for interferometric spectroscopy. We present mass-correlated rotational Raman spectra that represent the world's highest resolution scanned interferometric data and discuss the current and expected future limitations in achievable spectroscopic performance.
description: 8 pages, 12 figures, 1 table, submitted to the Journal of the Korean Physical Society
Decoherence puzzle in measurements of photons originating from electron-positron annihilation
Creators: name: Sharma, Sushil
name: Kumar, Deepak
name: Moskal, Pawel
Publisher: name: arXiv
Year: 2022
Subjects: subject: Popular Physics (physics.pop-ph)
subject: Instrumentation and Detectors (physics.ins-det)
subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: Entanglement of photons originating from the electron-positron annihilation has not been proven experimentally. Though the independent experiments performed so far unanimously confirm that correlation between the linear polarizations of back-to-back photons from the electron-positron annihilation is consistent with the assumption that these photons are entangled in polarization. Yet, unexpectedly, recent experiments differ as regards the correlation of polarization direction of back-to-back photons after the decoherence induced by scattering of one of these photons on the electron in the scattering material. In one of the experiments, the correlation before and after the decoherence of the photon state is the same and in the other experiment the scattering of one photon leads to a significant decrease in this correlation. Here we discuss this puzzle. The decoherent states were ensured by forcing one of the annihilation photons through prior scattering before the Compton kinematics based measurement of the polarization correlation. A comparison between the experimental setups used for the different measurements and the results obtained are briefly discussed, highlighting the parameters that are important for performing such measurements. Finally, the main features of the J-PET detector are presented with the schemes for performing similar measurements so that the results can be used as conclusive remarks for solving this puzzle. Solving the decoherence puzzle will have crucial consequences for basic studies of entanglement, as well as for the proposed application of polarisation of photons in positron emission tomography. In case if the correlation of polarisation of back-to-back photons from the electron-positron annihilation is the same before and after the scattering of these photons, then it will not be useful for the reduction of the scatter fraction in PET diagnostics.
Low-Temperature Gas Opacities with AESOPUS 2.0
Creators: name: Marigo, Paola
name: Aringer, Bernhard
name: Girardi, Leo
name: Bressan, Alessandro
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: This work introduces new low-temperature gas opacities, in the range 3.2 <= log(T/K) <= 4.5, computed with the AESOPUS code under the assumption of thermodynamic equilibrium (Marigo &_Aringer_2009). In comparison to the previous version AESOPUS 1.0, we updated and expanded molecular absorption to include 80 species, mostly using the recommended line lists currently available from the ExoMol and HITRAN databases. Furthermore, in light of a recent study, we revised the H- photodetachment cross section, added the free-free absorption of other negative ions of atoms and molecules, and updated the collision-induced absorption due to H2/H2, H2/H, H2/He, and H/He pairs. Using the new input physics, we computed tables of Rosseland mean opacities for several scaled-solar chemical compositions, including Magg et al. (2022)'s most recent one, as well as alpha-enhanced mixtures. The differences in opacity between the new AESOPUS 2.0 and the original AESOPUS 1.0 versions, as well as other sets of calculations, are discussed. The new opacities are released to the community via a dedicated web-page that includes both pre-computed tables for widely used chemical compositions, and a web-interface for calculating opacities on-the-fly for any abundance distribution.
description: Accepted for publication in ApJ. The paper includes 22 pages, 11 figures, 2 tables
Research on the Impact of Open Government Data on Innovation of Listed Companies
Creators: name: Fan, Jingsong
Publisher: name: Macquarie University
Year: 2025
Subjects: classificationCode: 350202
subject: Finance

description: In the context of the digital economy, open government data is a pivotal resource in advancing innovation and economic development. This study employs a multi-period difference-in- differences (DID) methodology to rigorously investigate the influence of open government data on corporate innovation and growth. The empirical analysis, drawing on data from A- share listed companies on China’s Shanghai and Shenzhen stock exchanges between 2012 and 2022, demonstrates that open government data has a statistically significant and positive impact on corporate innovation. This conclusion is further substantiated by a series of robustness checks. The mechanism analysis reveals that open government data fosters corporate innovation by enhancing the information environment and mitigating financing constraints. Further disaggregated analysis indicates that the innovation-enhancing effects of open government data are particularly pronounced in state-owned companies and firms with a lower proportion of independent directors. Crucially, open government data not only directly catalyzes corporate innovation but also contributes to increased productivity and economic efficiency, thereby generating significant indirect economic impacts. This study highlights the critical role of open government data as a catalyst for company innovation in the digital economy era. The findings suggest that policymakers should promote interdepartmental and cross-regional data sharing and reduce barriers to data access for companies. Moreover, it is recommended that differentiated policies be formulated in accordance with the specific characteristics of different types of companies to optimize the economic benefits derived from data openness.
Slow light with three-level atoms in metamaterial waveguides
Creators: name: Lavoie, Benjamin R.
name: Leung, Patrick M.
name: Sanders, Barry C.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Metamaterial is promising for enhancing the capability of plasmonic devices. We consider a cylindrical waveguide with three-level Λ atoms embedded in the dielectric core. By comparing metal cladding vs metamaterial cladding of a waveguide with Λ atoms in the core, we show that, for a fixed amount of slowing of light due to electromagnetically induced transparency, the metamaterial cladding outperforms in terms of the inherent loss.
description: 8 Pages, 6 figures