cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The security intelligence services of the private sector
Creators: name: Sage-Passant, Lewis
Publisher: name: Loughborough University
Year: 2023
Subjects: classificationCode: 440899
subject: Political science not elsewhere classified

description: Scholars have long viewed intelligence as the preserve of nation states. Where the term ‘private sector intelligence’ does appear in the academic literature, the focus is overwhelmingly on government contractors, rather than on intelligence activities for the benefit of private corporations. While there is a subset of the literature that has taken note of the intelligence services of corporations, these often view the field as a post-9/11 development, which has eroded a state monopoly of intelligence. This thesis demonstrates – through archival and secondary source research - that such a monopoly never existed. Private sector intelligence is at least as old as the organised intelligence activities of the nation state. Through semi-structured interviews and surveys with contemporary practitioners, this thesis demonstrates how private sector intelligence - via the framework of the Intelligence Cycle - resembles state intelligence. However, it also demonstrates that the private sector differs in important ways, such as through intelligence sharing and minimal oversight. This lack of oversight, this thesis argues, introduces ethical issues. This research demonstrates a need for an expansion of the scholarly literature to account for intelligence activities outside of the state; deepening our understanding of a wider intelligence field.
Comparing the Language of QAnon-related content on Parler, Gab, and Twitter
Creators: name: Sipka, Andrea
name: Hannak, Aniko
name: Urman, Aleksandra
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computers and Society (cs.CY)
subject: Social and Information Networks (cs.SI)
subject: FOS: Computer and information sciences

description: Parler, a "free speech" platform popular with conservatives, was taken offline in January 2021 due to the lack of moderation of hateful and QAnon- and other conspiracy-related content that allegedly made it instrumental in the organisation of the storming of the US Capitol on January 6. However, Parler co-existed with other social media platforms, and comparative studies are needed to draw conclusions about the prevalence of anti-social language, hate speech, or conspiracy theory content on the platform. We address this through a cross-platform comparison of posts related to QAnon. We compare posts with the hashtag #QAnon on Parler over a month-long period with posts on Twitter and Gab. In our analysis, Parler emerges as the platform with the highest average toxicity of the posts, though this largely stems from the distinctive way hashtags are used on this platform. Gab has the highest proportion of #QAnon posts with hate terms, and Parler and Twitter are similar in this respect. On all three platforms, posts mentioning female political figures, Democrats, or Donald Trump have more anti-social language than posts mentioning male politicians, Republicans, or Joe Biden. An analysis of entities mentioned in posts revealed differences in content - with Twitter posts mentioning prominent figures related to QAnon, while Parler and Gab posts mention entities related to conspiracies. Narrative analysis indicates that the discussion on Twitter centres on QAnon and is critical of it, Parler focuses on supporting Donald Trump, while on Gab the discussion focuses on more conspiratorial content, in relation to both Trump and other political figures.
Modeling an array of encapsulated germanium detectors
Creators: name: Kshetri, Ritesh
Publisher: name: arXiv
Year: 2012
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences
subject: 85-05

description: A probability model has been presented for understanding the operation of an array of encapsulated germanium detectors generally known as composite detector. The addback mode of operation of a composite detector has been described considering the absorption and scattering of gamma-rays. Considering up to triple detector hit events, we have obtained expressions for peak-to-total and peak-to-background ratios of the cluster detector, which consists of seven hexagonal closely packed encapsulated HPGe detectors. Results have been obtained for the miniball detectors comprising of three and four seven hexagonal closely packed encapsulated HPGe detectors. The formalism has been extended to the SPI spectrometer which is a telescope of the INTEGRAL satellite and consists of nineteen hexagonal closely packed encapsulated HPGe detectors. This spectrometer comprises of twelve detector modules surrounding the cluster detector. For comparison, we have considered a spectrometer comprising of nine detector modules surrounding the three detector configuration of miniball detector. In the present formalism, the operation of these sophisticated detectors could be described in terms of six probability amplitudes only. Using experimental data on relative efficiency and fold distribution of cluster detector as input, the fold distribution and the peak-to-total, peak-to-background ratios have been calculated for the SPI spectrometer and other composite detectors at 1332 keV. Remarkable agreement between experimental data and results from the present formalism has been observed for the SPI spectrometer.
description: Accepted in Journal of Instrumentation (JINST) 18th March 2012, INTEGRAL SPI modeling, 20 pages
Coherence of a qubit stored in Zeeman levels of a single optically trapped atom
Creators: name: Rosenfeld, Wenjamin
name: Volz, Jürgen
name: Weber, Markus
name: Weinfurter, Harald
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We experimentally investigate the coherence properties of a qubit stored in the Zeeman substates of the 5S1/2, F=1 hyperfine ground level of a single optically trapped Rb-87 atom. Larmor precession of a single atomic spin-1 system is observed by preparing the atom in a defined initial spin-state and then measuring the resulting state after a programmable period of free evolution. Additionally, by performing quantum state tomography, maximum knowledge about the spin coherence is gathered. By using an active magnetic field stabilization and without application of a magnetic guiding field we achieve transverse and longitudinal dephasing times of T2*=75..150 \mus and T1>0.5 ms respectively. We derive the light-shift distribution of a single atom in the approximately harmonic potential of a dipole trap and show that the measured atomic spin coherence is limited mainly by residual position- and state-dependent effects in the optical trapping potential. The improved understanding enables longer coherence times, an important prerequisite for future applications in long-distance quantum communication and computation with atoms in optical lattices or for a loophole-free test of Bell's inequality.
description: 9 pages, 5 figures
Early Planet Formation in Embedded Disks (eDisk): A first look at the Class 0 prostostar GSS30 IRS3
Creators: name: Santamaría-Miranda, Alejandro
Publisher: name: Zenodo
Year: 2023

description: Protoplanetary disks are the places where planets are formed during the star formation process. In recent years, the focus of research efforts to better understand planet formation has been on Class II sources, identifying substructures in approximately one hundred of them. The origins of these substructures, however, remain a topic of debate. Planet formation is the leading theory among the different mechanisms proposed to explain the formation of these substructures. To investigate whether these substructures are the result of planet formation, it is necessary to study the earlier evolutionary stages of protoplanetary disks, specifically Class 0/I disks, which have not been studied in detail. The ALMA Large Program "Early Planet Formation in Embedded Disks (eDISK)" aims to systematically study the origin of substructures in Class 0/I protoplanetary disks. As part of the program, we present observations of the Class 0 protostar GSS30 IRS3, which were conducted using ALMA Band 6 (1.3 mm) at a spatial resolution of 8 au. Observation targeted continuum and several molecular lines (12CO, 13CO, C18O, c-C3H2), which were all detected. While no apparent substructures such as gaps or spirals were observed, we noted a disk asymmetry. A fit in the visibility plane suggests that the asymmetry may be a sharp substructure. The 12CO traces the mass loss from the protostar disk, revealing a low-velocity molecular outflow with a mass loss rate of 6×105 M⊙ yr−1 and a high-velocity outflow component. Using the rotation curve analysis of the C18O isotopologue, which mainly traces the Keplerian disk, we derived a dynamical mass of 0.235 ± 0.039 M⊙ IRS3. A warp is detected in the C18O emission line, which we interpret it as infalling gas. The gas-to-dust size ratio for IRS3 was found to be 1.64, indicating no evolution of this ratio compared to Class II sources.
Een Geschilderde Lijst Innovatie Door Gillis Coignet Of Gillis Mostaert? Hooiwagen, Parijs, Louvre
Creators: name: Goukens, Lode
Publisher: name: Zenodo
Year: 2016
Subjects: 16th century flemish art
northern renaissance
Antwerp
flemish painting
Gillis Coignet
Gillis Mostaert

description: paper for the course Geschiedenis van de Beeldende Kunsten in de Nederlanden II (2015-2016)
Large-scale emission in FR I jets
Creators: name: Bordas, Pol
name: Bosch-Ramon, Valentí
name: Perucho, Manel
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The termination structures of the jets of Fanaroff & Riley galaxies are observed to produce extended non-thermal emission in a wide frequency range. The study of these structures can provide valuable insights on the conditions for particle acceleration and radiation at the shock fronts.We have studied the thermal and non-thermal emission that can be expected from the jet termination regions of Fanaroff & Riley type I sources. The broadband emission from these galaxies has been recently extended to include the high-energy gamma-ray domain, owing to the Fermi detection of Cen A lobes. Exploring the physics behind the jet/medium interactions in FRI can provide valuable insights on the conditions for particle acceleration and radiation in the jet termination shocks. Making use of the results of a fully relativistic numerical simulation code of the evolution of a FRI jet we model the expected radiative output and predict spectra and lightcurves of both thermal and non-thermal emission at different source ages.
description: Proceedings of the High Energy Phenomena in Relativistic Outflows III conference
Extremality, Left-Modularity and Semidistributivity
Creators: name: Mühle, Henri
Publisher: name: arXiv
Year: 2021
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 06D75

description: In this article we investigate the relations between three classes of lattices each extending the class of distributive lattices in a different way. In particular, we consider join-semidistributive, join-extremal and left-modular lattices, respectively. Our main motivation is a recent result by Thomas and Williams proving that every semidistributive, extremal lattice is left modular. We prove the converse of this on a slightly more general level. Our main result asserts that every join-semidistributive, left-modular lattice is join extremal. We also relate these properties to the topological notion of lexicographic shellability.
description: 10 pages, 5 figures. Comments are welcome
Plasma diagnostic in eruptive prominences from SDO/AIA observations at 304 Å
Creators: name: Labrosse, Nicolas
name: McGlinchey, Kristopher
Publisher: name: arXiv
Year: 2011
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Plasma Physics (physics.plasm-ph)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Context. Theoretical calculations have shown that when solar prominences move away from the surface of the Sun, their radiative output is affected via the Doppler dimming or brightening effects. Aims. In this paper we ask whether observational signatures of the changes in the radiative output of eruptive prominences can be found in EUV (extreme ultraviolet) observations of the first resonance line of ionised helium at 304 Å. We also investigate whether these observations can be used to perform a diagnostic of the plasma of the eruptive prominence. Methods. We first look for suitable events in the SDO/AIA database. The variation of intensity of arbitrarily selected features in the 304 channel is studied as a function of velocity in the plane of the sky. These results are then compared with new non-LTE radiative transfer calculations of the intensity of the He II 304 resonance line. Results. We find that observations of intensities in various parts of the four eruptive prominences studied here are sometimes consistent with the Doppler dimming effect on the He II 304 Å line. However, in some cases, one observes an increase in intensity in the 304 channel with velocity, in contradiction to what is expected from the Doppler dimming effect alone. The use of the non-LTE models allows us to explain the different behaviour of the intensity by changes in the plasma parameters inside the prominence, in particular the column mass of the plasma and its temperature. Conclusions. The non-LTE models used here are more realistic than what was used in previous calculations. They are able to reproduce qualitatively the range of observations from SDO/AIA analysed in this study. Thanks to non-LTE modelling, we can infer the plasma parameters in eruptive prominences from SDO/AIA observations at 304 Å.
description: 7 pages, 8 figures. Movies available at http://www.astro.gla.ac.uk/users/labrosse/aa17801/
Low-intensity pulsed ultrasound promotes mesenchymal stem cell transplantation-based articular cartilage regeneration via inhibiting the TNF signaling pathway
Creators: name: Chen, Yiming
name: Yang, Huiyi
name: Wang, Zhaojie
name: Zhu, Rongrong
name: Cheng, Liming
name: Cheng, Qian
Publisher: name: arXiv
Year: 2021
Subjects: subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: Background: Mesenchymal stem cell (MSC) transplantation therapy is highly investigated for the regenerative repair of cartilage defects. Low-intensity pulsed ultrasound (LIPUS) has the potential to promote chondrogenic differentiation of MSCs. However, its underlying mechanism remains unclear. Here, we investigated the promoting effects and mechanisms underlying LIPUS stimulation on the chondrogenic differentiation of human umbilical cord mesenchymal stem cells (hUC-MSCs) and further evaluated its regenerative application value in articular cartilage defects in rats. Methods: LIPUS was applied to stimulate cultured hUC-MSCs and C28/I2 cells in vitro. Immunofluorescence staining, qPCR analysis, and transcriptome sequencing were used to detect mature cartilage-related markers of gene and protein expression for a comprehensive evaluation of differentiation. Injured articular cartilage rat models were established for further hUC-MSC transplantation and LIPUS stimulation in vivo. Histopathology and H&E staining were used to evaluate the repair effects of the injured articular cartilage with LIPUS stimulation. Results: The results showed that LIPUS stimulation with specific parameters effectively promoted the expression of mature cartilage-related genes and proteins, inhibited TNF-α gene expression in hUC-MSCs, and exhibited anti-inflammation in C28/I2 cells. In addition, the articular cartilage defects of rats were significantly repaired after hUC-MSC transplantation and LIPUS stimulation. Conclusions: Taken together, LIPUS stimulation could realize articular cartilage regeneration based on hUC-MSC transplantation due to the inhibition of the TNF signaling pathway, which is of clinical value for the relief of osteoarthritis.
description: 19 pages, 7 figures
Spectrum of the transfer matrices of the spin chains associated with the $A^{(2)}_3$ Lie algebra
Creators: name: Li, Guang-Liang
name: Cao, Junpeng
name: Xu, Xiao-Tian
name: Hao, Kun
name: Sun, Pei
name: Yang, Tao
name: Yang, Wen-Li
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mathematical Physics (math-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: We study the exact solution of quantum integrable system associated with the $A^{(2)}_3$ twist Lie algebra, where the boundary reflection matrices have non-diagonal elements thus the $U(1)$ symmetry is broken. With the help of the fusion technique, we obtain the closed recursive relations of the fused transfer matrices. Based on them, together with the asymptotic behaviors and the values at special points, we obtain the eigenvalues and Bethe ansatz equations of the system. We also show that the method is universal and valid for the periodic boundary condition where the $U(1)$ symmetry is reserved. The results in this paper can be applied to studying the exact solution of the $A^{(2)}_n$-related integrable models with arbitrary $n$.
description: 26 pages
Intelligent Medical Image Analyzer
Creators: name: Aribisala, Benjamin
name: Oluwatoyin Enikuomehin
name: Akinyemi, Rufus
Publisher: name: Sci-GaIA Open Access Repository
Year: 2016

description: The proposed system is an e-infrastructure for processing medical images so that the processed data could be used for decision support during diagnosis or clinical research. The two categories of people who will most likely use our tools are clinicians and researchers conducting medical research. The frontend of the proposed system will be built using PHP, HTML, javascript and xamp. The frontend will be user friendly, interactive and will allow uploading of medical images.  It will also contain options for image processing and report generation. The backend will contain MATLAB, C++ compiler and some specialized medical image processing software packages and some test data. The proposed system will also have some storage allowance for image uploads by the user. Once images are uploaded, the software relevant for processing the particular uploaded images will be selected automatically and applied on the images. The image storage model will allow some specific types of medical images that are commonly used in medical field.
Rotation Curve of Galaxies by the Force Induced by Mass of Moving Particles
Creators: name: Ihm, Kyuwook
name: Lee, Kyoung-Jea
Publisher: name: arXiv
Year: 2012
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: We suggest that there is a novel force which is generated by the mass of relatively moving particles. The new force which we named Mirinae Force is a counterpart of the magnetic force operating between electrically charged moving particles. Instead of using the conventional dark matter, we applied the mirinae force to a particular model system of the spiral galaxy in which most of the galaxy's mass is located within the central region where some portion of the inner mass is in revolving motion at a relativistic speed. The calculation yielded three important results that illustrate the existence of mirinae force and validate the proposed model: First, the mirinae force in this model explains why most of the matters in the galactic disk are in the circular motion which is similar to cycloid. Second, the mirinae force well explains not only the flat rotation curve but also the varied slope of the rotation curve observed in the spiral galaxies. Third, at the flat velocity of 220 Km/s, the inner mass of the Milky Way calculated by using the proposed model is 6.0\times10^11 M\odot, which is very close to 5.5\times10^11 M\odot (r <50 Kpc, including Leo I) estimated by using the latest kinematic information. This means that the mirinae force well takes the place of the dark matter of the Milky Way.
The bright-end of the luminosity function at z~9
Creators: name: Laporte, N.
name: Pello, R.
name: Hayes, M.
name: Schaerer, D.
name: Boone, F.
name: Richard, J.
name: Borgne, J. F. Le
name: Kneib, J. P.
name: Combes, F.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We report new constraints on the galaxy luminosity function at z~9 based on observations carried out with ESO/VLT FORS2, HAWK-I and X-Shooter around the lensing cluster A2667, as part of our project aimed at selecting z~7-10 candidates accessible to spectroscopy. Only one J-dropout source was selected in this field fulfilling the color and magnitude criteria. This source was recently confirmed as a mid-z interloper based on X-Shooter spectroscopy. The depth and the area covered by our survey are well suited to set strong constraints on the bright-end of the galaxy luminosity function and hence on the star formation history at very high redshift. The non-detection of reliable J-dropout sources over the ~36arcmin2 field of view towards A2667 was used to carefully determine the lens-corrected effective volume and the corresponding upper-limit on the density of sources. The strongest limit is obtained for Phi(M_{1500}=-21.4+/-0.50)<6.70x10^{-6}Mpc^{-3}mag^{-1} at z~9. A maximum-likelihood fit of the luminosity function using all available data points including the present new result yields M*>-19.7 with fixed alpha=-1.74 and Phi*=1.10x10^{-3}Mpc^{-3}. The corresponding star formation rate density should be rho_{SFR}<5.97x10^{-3}M_{solar}/yr/Mpc^{3} at z~9. These results are in good agreement with the most recent estimates already published in this range of redshift and for this luminosity domain. This new result confirms the decrease in the density of luminous galaxies at very high-redshift, hence providing strong constraints for the design of future surveys aiming to explore the very high-redshift Universe.
description: 4 pages, 2 figures, accepted for publication in A&A Letters
Soil Nutrients and understory species associated with lodgepole pine (Pinus contorta Loudon) forests in the Lower Boreal-Cordilleran Ecoregion of Alberta
Creators: name: Szwaluk, Kevin Samuel
Publisher: name: Graduate Studies
Year: 2001
Subjects: subject: AC1 .T484 2001 S99

description: Bibliography: p. 69-80.
LkCa 15: A Young Exoplanet Caught at Formation?
Creators: name: Kraus, Adam L.
name: Ireland, Michael J.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Young and directly imaged exoplanets offer critical tests of planet-formation models that are not matched by RV surveys of mature stars. These targets have been extremely elusive to date, with no exoplanets younger than 10--20 Myr and only a handful of direct-imaged exoplanets at all ages. We report the direct imaging discovery of a likely (proto)planet around the young (~2 Myr) solar analog LkCa 15, located inside a known gap in the protoplanetary disk (a "transitional disk"). Our observations use non-redundant aperture masking interferometry at 3 epochs to reveal a faint and relatively blue point source ($M_K'=9.1+/-0.2, K'-L'=0.98+/-0.22), flanked by approximately co-orbital emission that is red and resolved into at least two sources (M_L'=7.5+/-0.2, K'-L'=2.7+/-0.3; M_L'=7.4+/-0.2, K'-L'=1.94+/-0.16). We propose that the most likely geometry consists of a newly-formed (proto)planet that is surrounded by dusty material. The nominal estimated mass is ~6 M_{Jup} according to the 1 Myr hot-start models. However, we argue based on its luminosity, color, and the presence of circumplanetary material that the planet has likely been caught at its epoch of assembly, and hence this mass is an upper limit due to its extreme youth and flux contributed by accretion. The projected separations (71.9 +/- 1.6 mas, 100.7 +/- 1.9 mas, and 88.2 +/- 1.8 mas) and deprojected orbital radii (16, 21, and 19 AU) correspond to the center of the disk gap, but are too close to the primary star for a circular orbit to account for the observed inner edge of the outer disk, so an alternate explanation (i.e., additional planets or an eccentric orbit) is likely required. This discovery is the first direct evidence that at least some transitional disks do indeed host newly-formed (or forming) exoplanetary systems, and the observed properties provide crucial insight into the gas giant formation process.
description: Accepted to ApJ; 15 pages, 4 figures, 2 tabls in emulateapj format
Tuning poly (L-lactic acid) scaffolds with poly(amidoamine) and poly(propylene imine) dendrimers: surface chemistry, biodegradation and biocompatibility
Creators: name: Ganjalinia, Atiyeah
name: Akbari, Somaye
name: Solouk, Atefeh
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Space Science
subject: Medicine
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences

description: The aim of this comparative study was focused on the surface chemistry, in vitro biodegradation and biocompatibility of poly(L-lactic acid) (PLLA) scaffolds incorporated with poly(amidoamine) (PAMAM) and poly(propylene imine) (PPI) dendrimers. The functionality of these two types of dendrimers from second, third and fifth generations (G2, G3 and G5) onto the surface of PLLA film and electrospun scaffolds was investigated and characterized by a series of analyses including X-ray photoelectron spectroscopy, atomic force microscope, Fourier transform infrared spectroscopy, contact angle, scanning electron microscope, weight loss, water uptake and pH changes after degradation in different media. The successful incorporation of dendrimers into the surface of PLLA scaffolds was observed. PPI-G5 could further increase the hydrophilicity and surface roughness of PLLA scaffolds compared to PPI-G3 and PPI-G2. Further improvement on PLLA surface chemistry was observed when PAMAM-G5 was applied compared to PPI-G5. The pH value of Roswell Park Memorial Institute Medium (RPMI) media containing raw electrospun PLLA scaffold decreased to 5.2 from its original value of 7.2. However, the local acidity of RPMI medium caused by PLLA hydrolysis was greatly reduced on the surface of PLLA/PAMAM-G5 and PLLA/PPI-G5 with pH values of 7.8 and 7.5, respectively. Moreover, the viability of fibroblast cells on the surface of PLLA/dendrimer scaffolds was considerably increased compared to raw PLLA. Fibroblasts showed higher attachment and homogeneous spread morphology on the surface of PLLA/PAMAM-G5 and PLLA/PPI-G5. These observations underline the favorable surface properties of PLLA scaffolds incorporated with dendrimers, to be used as a biodegradable biocompatible scaffold tailored for biomedical applications.
Herschel-ATLAS Galaxy Counts and High Redshift Luminosity Functions: The Formation of Massive Early Type Galaxies
Creators: name: Lapi, A.
name: Gonzalez-Nuevo, J.
name: Fan, L.
name: Bressan, A.
name: De Zotti, G.
name: Danese, L.
name: Negrello, M.
name: Dunne, L.
name: Eales, S.
name: Maddox, S.
name: Auld, R.
name: Baes, M.
name: Bonfield, D. G.
name: Buttiglione, S.
name: Cava, A.
name: Clements, D. L.
name: Cooray, A.
name: Dariush, A.
name: Dye, S.
name: Fritz, J.
name: Herranz, D.
name: Hopwood, R.
name: Ibar, E.
name: Ivison, R.
name: Jarvis, M. J.
name: Kaviraj, S.
name: Lopez-Caniego, M.
name: Massardi, M.
name: Michalowski, M. J.
name: Pascale, E.
name: Pohlen, M.
name: Rigby, E.
name: Rodighiero, G.
name: Serjeant, S.
name: Smith, D. J. B.
name: Temi, P.
name: Wardlow, J.
name: van der Werf, P.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Exploiting the Herschel-ATLAS Science Demonstration Phase (SDP) survey data, we have determined the luminosity functions (LFs) at rest-frame wavelengths of 100 and 250 micron and at several redshifts z>1, for bright sub-mm galaxies with star formation rates (SFR) >100 M_sun/yr. We find that the evolution of the comoving LF is strong up to z~2.5, and slows down at higher redshifts. From the LFs and the information on halo masses inferred from clustering analysis, we derived an average relation between SFR and halo mass (and its scatter). We also infer that the timescale of the main episode of dust-enshrouded star formation in massive halos (M_H>3*10^12 M_sun) amounts to ~7*10^8 yr. Given the SFRs, which are in the range 10^2-10^3 M_sun/yr, this timescale implies final stellar masses of order of 10^11-10^12 M_sun. The corresponding stellar mass function matches the observed mass function of passively evolving galaxies at z>1. The comparison of the statistics for sub-mm and UV selected galaxies suggests that the dust-free, UV bright phase, is >10^2 times shorter than the sub-mm bright phase, implying that the dust must form soon after the onset of star formation. Using a single reference Spectral Energy Distribution (SED; the one of the z~2.3 galaxy SMM J2135-0102), our simple physical model is able to reproduce not only the LFs at different redshifts > 1 but also the counts at wavelengths ranging from 250 micron to ~1 mm. Owing to the steepness of the counts and their relatively broad frequency range, this result suggests that the dispersion of sub-mm SEDs of z>1 galaxies around the reference one is rather small.
description: 33 pages, 19 figures, 2 tables. Accepted by ApJ
Mean-field synchronization model for open-loop, swirl controlled thermoacoustic system
Creators: name: Singh, Samarjeet
name: Dutta, Ankit Kumar
name: Dhadphale, Jayesh M.
name: Roy, Amitesh
name: Chaudhuri, Swetaprovo
name: Sujith, R. I.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: Open-loop control is known to be an effective strategy for controlling self-excited thermoacoustic oscillations in turbulent combustors. In this study, we investigate the suppression of thermoacoustic instability in a lean premixed, laboratory-scale combustor using experiments and analysis. Starting with a self-excited thermoacoustic instability in the combustor, we find that a progressive increase in the swirler rotation rate transitions the system from thermoacoustic instability to the suppressed state through a state of intermittency. To model such transition while also quantifying the underlying synchronization characteristics, we extend the model of Dutta et al. [Phys. Rev. E 99, 032215 (2019)] by introducing a feedback between the ensemble of mean-field phase oscillators and the basis expansion of the acoustic pressure governing equation. The assumption that coupling strength among the oscillators is a linear combination of acoustic and swirler rotation frequency is justified \textit{a posteriori}. The link between the model and experimental results is quantitatively established by implementing an optimization algorithm for model parameter estimation. We show that the model replicates the bifurcation characteristics, time series, probability density function (PDF), and power spectral density (PSD) of the various dynamical states observed during the transition to the suppressed state, to excellent accuracy. Specifically, the model captures the change in the PDF of pressure and heat release rate fluctuations from a bimodal distribution during thermoacoustic instability to a unimodal distribution during suppression. Finally, we discuss the global and local flame dynamics and show that the model qualitatively captures various aspects of spatio-temporal synchronization that underlies the transition.
description: S.S. and A. K. D. contributed equally in this paper. 8 pages and 6 figures
PSI/J: A Portable Interface for Submitting, Monitoring, and Managing Jobs
Creators: name: Hategan-Marandiuc, Mihael
name: Merzky, Andre
name: Collier, Nicholson
name: Maheshwari, Ketan
name: Ozik, Jonathan
name: Turilli, Matteo
name: Wilke, Andreas
name: Wozniak, Justin M.
name: Chard, Kyle
name: Foster, Ian
name: da Silva, Rafael Ferreira
name: Jha, Shantenu
name: Laney, Daniel
Publisher: name: arXiv
Year: 2023
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: It is generally desirable for high-performance computing (HPC) applications to be portable between HPC systems, for example to make use of more performant hardware, make effective use of allocations, and to co-locate compute jobs with large datasets. Unfortunately, moving scientific applications between HPC systems is challenging for various reasons, most notably that HPC systems have different HPC schedulers. We introduce PSI/J, a job management abstraction API intended to simplify the construction of software components and applications that are portable over various HPC scheduler implementations. We argue that such a system is both necessary and that no viable alternative currently exists. We analyze similar notable APIs and attempt to determine the factors that influenced their evolution and adoption by the HPC community. We base the design of PSI/J on that analysis. We describe how PSI/J has been integrated in three workflow systems and one application, and also show via experiments that PSI/J imposes minimal overhead.
Black Hole Superradiance in Dynamical Chern-Simons Gravity
Creators: name: Alexander, Stephon
name: Gabadadze, Gregory
name: Jenks, Leah
name: Yunes, Nicolás
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Black hole superradiance provides a window into the dynamics of light scalar fields and their interactions close to a rotating black hole. Due to the rotation of the black hole, the amplitude of the scalar field becomes magnified, leading to a "black hole bomb" effect. Recent work has demonstrated that rotating black holes in dynamical Chern-Simons gravity possess unique structures, the "Chern-Simons caps," which may influence the behavior of matter near the black hole. Motivated by the presence of these caps, we study superradiance in dynamical Chern-Simons gravity in the context of a slowly rotating black hole. We find that additional modes are excited and contribute to the superradiance beyond what is expected for a Kerr black hole. Studying the superradiant spectrum of perturbations, we find that the Chern-Simons contributions give rise to small corrections to the angular dependence of the resulting scalar cloud. Finally, we comment on potential observable consequences and future avenues for investigation.
description: Error in Eq. 51-53 and 69-71 corrected, updated discussion
Expansion of 1D polarized superfluids: The FFLO state reveals itself
Creators: name: Lu, Hong
name: Baksmaty, L. O.
name: Bolech, C. J.
name: Pu, Han
Publisher: name: arXiv
Year: 2012
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We study the expansion dynamics of a one dimensional polarized Fermi gas after sudden release from confinement using both the mean-field Bogoliubov-de Gennes and the numerically exact Time-Evolving Block Decimation methods. Our results show that experimentally observable spin density modulations directly related to the presence of a Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) state develop during the expansion of the cloud, providing incontrovertible evidence of this long-sought state.
description: 4 pages, 5 figures + 2 pages of supplementary material
Fabrication of MWCNT and phenolic epoxy resin reinforced PVDF: a composite with low dielectric loss and excellent mechanical properties
Creators: name: Zhang, Xiaoxin
name: He, Shuai
name: Lian, Weiqiang
name: Peng, Guirong
name: Liu, Shuohai
name: Zhan, Zaiji
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Biophysics
subject: Space Science
subject: Medicine
subject: Physiology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Inorganic Chemistry
subject: FOS: Chemical sciences
subject: Hematology

description: In the article, PVDF-based composites reinforced by MWCNT and phenolic epoxy resin were prepared by solution casting method to get a material with excellent mechanical properties and high dielectric properties and breakdown strength when conductor is as filler. The experimental results demonstrate that dielectric constant of m-MWCNT/EP/PVDF composites (εr  = 32 at 100 Hz) is twice times higher than that of the EP/PVDF composites, and is about three times higher than that of the pure PVDF. The dielectric loss is not higher than that of the others (Tan δ = 0.3 at 100 Hz). The breakdown strength of the composites is higher than 100 MV/m, which is superior to most of composites modified with conductors. The breakdown strength for most of composites modified with conductors is under 100 MV/m. The elongation at break of m-MWCNT/EP/PVDF composites keeps 500% and the tensile yield strength increases continuously.
From Cauchy's determinant formula to bosonic and fermionic immanant identities
Creators: name: Khare, Apoorva
name: Sahi, Siddhartha
Publisher: name: arXiv
Year: 2022
Subjects: subject: Representation Theory (math.RT)
subject: Combinatorics (math.CO)
subject: Group Theory (math.GR)
subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 05E05 (primary), 15A15, 15A24, 20C15 (secondary)

description: Cauchy's determinant formula (1841) involving $\det ((1-u_i v_j)^{-1})$ is a fundamental result in symmetric function theory. It has been extended in several directions, including a determinantal extension by Frobenius [J. reine angew. Math. 1882] involving a sum of two geometric series in $u_i v_j$. This theme also resurfaced in a matrix analysis setting in a paper by Horn [Trans. Amer. Math. Soc. 1969] - where the computations are attributed to Loewner - and in recent works by Belton-Guillot-Khare-Putinar [Adv. Math. 2016] and Khare-Tao [Amer. J. Math. 2021]. These formulas were recently unified and extended in [Trans. Amer. Math. Soc. 2022] to arbitrary power series, with commuting/bosonic variables $u_i, v_j$. In this note we formulate analogous permanent identities, and in fact, explain how all of these results are a special case of a more general identity, for any character - in fact, any complex class function - of any finite group that acts on the bosonic variables $u_i$ and on the $v_j$ via signed permutations. (We explain why larger linear groups do not work, via a - perhaps novel - "symmetric function" characterization of signed permutation matrices that holds over any integral domain.) We then provide fermionic analogues of these formulas, as well as of the closely related Cauchy product identities.
description: Definition 2.1 (here and in the published version in the European Journal of Combinatorics) is corrected, to also include the nonzero coefficients in the class function. This is required when dealing with class functions that have non-integer coefficients; that said, no results in the paper get changed in their hypotheses or assertions
Deep learning of invariant spatio-temporal features from video
Creators: name: Chen, Bo
Publisher: name: University of British Columbia
Year: 2010

description: We present a novel hierarchical and distributed model for learning invariant spatio-temporal features from video. Our approach builds on previous deep learning methods and uses the Convolutional Restricted Boltzmann machine (CRBM) as a building block. Our model, called the Space-Time Deep Belief Network (ST-DBN), aggregates over both space and time in an alternating way so that higher layers capture more distant events in space and time. The model is learned in an unsupervised manner. The experiments show that it has good invariance properties, that it is well-suited for recognition tasks, and that it has reasonable generative properties that enable it to denoise video and produce spatio-temporal predictions.
Index theorems for graph-parametrized optimal control problems
Creators: name: Agrachev, Andrei
name: Baranzini, Stefano
name: Beschastnyi, Ivan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optimization and Control (math.OC)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: In this paper we prove Morse index theorems for a big class of constrained variational problems on graphs. Such theorems are useful in various physical and geometric applications. Our formulas compute the difference of Morse indices of two Hessians related to two different graphs or two different sets of boundary conditions. Several applications such as the iteration formulas or lower bounds for the index are proved.
description: 30 pages, 4 figures
Stagnation Detection Meets Fast Mutation
Creators: name: Doerr, Benjamin
name: Rajabi, Amirhossein
Publisher: name: arXiv
Year: 2022
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Computer and information sciences

description: Two mechanisms have recently been proposed that can significantly speed up finding distant improving solutions via mutation, namely using a random mutation rate drawn from a heavy-tailed distribution ("fast mutation", Doerr et al. (2017)) and increasing the mutation strength based on stagnation detection (Rajabi and Witt (2020)). Whereas the latter can obtain the asymptotically best probability of finding a single desired solution in a given distance, the former is more robust and performs much better when many improving solutions in some distance exist. In this work, we propose a mutation strategy that combines ideas of both mechanisms. We show that it can also obtain the best possible probability of finding a single distant solution. However, when several improving solutions exist, it can outperform both the stagnation-detection approach and fast mutation. The new operator is more than an interleaving of the two previous mechanisms and it also outperforms any such interleaving.
description: 28 pages. Full version of a paper appearing at EvoCOP 2022
Breath analysis by ultra-sensitive broadband laser spectroscopy detects SARS-CoV-2 infection
Creators: name: Liang, Qizhong
name: Chan, Ya-Chu
name: Toscano, Jutta
name: Bjorkman, Kristen K.
name: Leinwand, Leslie A.
name: Parker, Roy
name: Nozik, Eva S.
name: Nesbitt, David J.
name: Ye, Jun
Publisher: name: arXiv
Year: 2022
Subjects: subject: Medical Physics (physics.med-ph)
subject: Machine Learning (cs.LG)
subject: Biological Physics (physics.bio-ph)
subject: Chemical Physics (physics.chem-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Rapid testing is essential to fighting pandemics such as COVID-19, the disease caused by the SARS-CoV-2 virus. Exhaled human breath contains multiple volatile molecules providing powerful potential for non-invasive diagnosis of diverse medical conditions. We investigated breath detection of SARS-CoV-2 infection using cavity-enhanced direct frequency comb spectroscopy (CE-DFCS), a state-of-the-art laser spectroscopic technique capable of a real-time massive collection of broadband molecular absorption features at ro-vibrational quantum state resolution and at parts-per-trillion volume detection sensitivity. Using a total of 170 individual breath samples (83 positive and 87 negative with SARS-CoV-2 based on Reverse Transcription Polymerase Chain Reaction tests), we report excellent discrimination capability for SARS-CoV-2 infection with an area under the Receiver-Operating-Characteristics curve of 0.849(4). Our results support the development of CE-DFCS as an alternative, rapid, non-invasive test for COVID-19 and highlight its remarkable potential for optical diagnoses of diverse biological conditions and disease states.
The H1 Data Preservation Project
Creators: name: South, David M.
name: Steder, Michael
Publisher: name: arXiv
Year: 2012
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Digital Libraries (cs.DL)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: The H1 data preservation project was started in 2009 as part of the global data preservation initiative in high-energy physics, DPHEP. In order to retain the full potential for future improvements, the H1 Collaboration aims for level 4 of the DPHEP recommendations, which requires the full simulation and reconstruction chain as well as the data to be preserved for future analysis. A major goal of the H1 project is therefore to provide secure, long-lived and validated access to the H1 data and analysis software, which is realised in collaboration with DESY-IT using virtualisation techniques. By implementing such a system, it is hoped that the lifetime of the unique ep collision data from HERA will be extended, providing the possibility for novel analysis in the future. The preservation of the data and software is performed alongside a consolidation programme of digital and non-digital documentation, some of which dates back to the early 1980s. A new organisational model of the H1 Collaboration, reflecting the change to the long term phase, is to be adopted in July 2012.
description: Proceedings of poster shown at the 2012 International Conference on Computing in High Energy and Nuclear Physics (CHEP 2012). 6 pages, 5 figures