cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Culture and production of Lucilia sericata Meigen (1826) larvae for rearing stinging catfish Heteropneustes fossilis (Bloch, 1794) using poultry waste
Creators: name: Al-Asif, Abdulla-
Publisher: name: figshare
Year: 2022
Subjects: Invertebrate biology
Vertebrate biology
Zoology not elsewhere classified
Animal growth and development
Animal management
Animal nutrition
Environmental studies in animal production
Veterinary sciences not elsewhere classified

description: The fly larvae (Lucilia sericata) are being used as an alternative protein source in any kind of animal feed as it reduces the cost of preparation of feed. This current study focused on the physico-chemical and proximate properties of raw poultry waste, while this study also revealed the production process of fly larvae and the proximate composition of it. The poultry waste was collected from Suvro poultry farm, Sutiakhali, Mymensingh, then the physic-chemical properties of the raw poultry waste were determined using different procedures. Three treatments were considered for production of fly larvae, T 1 (3 kg), T 2 (6 kg) and T 3 (9 kg) in a 15 kg capacity tray with three replications. After production, the proximate composition were also measured of fly larvae. Physico-chemical properties such as, color, odor, texture, temperature, pH, total solids (TSS+TDS), chemical oxygen demand, dissolved oxygen, alkalinity, available N, available P, and fiber in raw poultry waste were determined and presented. Proximate composition such as, moisture, total N, total P, available N, total Ca, ash and crude fiber were found in significant amount in the poultry waste. It was found that T 3 (1350±68g) produced highest volume of live maggot compared to the other treatments, but T 2 (17.50±1.10%) produced highest percentage volume. The proximate compositions of fly larvae were assessed and found 56.60±0.25% protein value in it, suggesting that fly larvae could be the protein replacer in fish feed. The result of this study revealed cheap protein source in aquaculture production, such as production and rearing of stinging catfish Heteropneustes fossilis, and the findings might be helpful for cost reduction in aquaculture operation.
Cold dark matter plus not-so-clumpy dark relics
Creators: name: Diamanti, Roberta
name: Ando, Shin'ichiro
name: Gariazzo, Stefano
name: Mena, Olga
name: Weniger, Christoph
Publisher: name: arXiv
Year: 2017
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Various particle physics models suggest that, besides the (nearly) cold dark matter that accounts for current observations, additional but sub-dominant dark relics might exist. These could be warm, hot, or even contribute as dark radiation. We present here a comprehensive study of two-component dark matter scenarios, where the first component is assumed to be cold, and the second is a non-cold thermal relic. Considering the cases where the non-cold dark matter species could be either a fermion or a boson, we derive consistent upper limits on the non-cold dark relic energy density for a very large range of velocity dispersions, covering the entire range from dark radiation to cold dark matter. To this end, we employ the latest Planck Cosmic Microwave Background data, the recent BOSS DR11 and other Baryon Acoustic Oscillation measurements, and also constraints on the number of Milky Way satellites, the latter of which provides a measure of the suppression of the matter power spectrum at the smallest scales due to the free-streaming of the non-cold dark matter component. We present the results on the fraction $f_{\rm ncdm}$ of non-cold dark matter with respect to the total dark matter for different ranges of the non-cold dark matter masses. We find that the 2$σ$ limits for non-cold dark matter particles with masses in the range 1--10 keV are $f_{\rm ncdm}\leq0.29$ (0.23) for fermions (bosons), and for masses in the 10--100 keV range they are $f_{\rm ncdm}\leq0.43$ (0.45), respectively.
description: 16 pages, 6 figures; matches the version accepted for publication
Aktivitäten-geleitete Aphasie Diagnostik (AgAD) – Evaluation der konzipierten Screening-Aufgabe «Terminvereinbarung» in der Praxis
Creators: name: Kramer, Fabienne
Publisher: name: Interkantonale Hochschule für Heilpädagogik
Year: 2024
Subjects: Logopädie
Masterarbeit
Aphasie
Diagnostik
Aktivität
ICF
Evaluation

description: Das kooperative Forschungsprojekt Aktivitäten-geleitete Aphasie Diagnostik (AgAD) der Interkantonalen Hochschule für Heilpädagogik Zürich (HfH) und der Schweizerischen Hochschule für Logopädie Rorschach (SHLR) hat zum Ziel, ein Diagnostikinstrument zu entwickeln, dass die sprachlichen Einschränkungen von Personen mit einer Aphasie konsequent von der Aktivitätsebene ausgehend erfasst. Im Rahmen des Studienprojekts G, welches ebenfalls Teil des Masterstudiums Logopädie ist, wurde eine Screening-Aufgabe zur Überprüfung der sprachlichen Aktivität einer Terminvereinbarung konzipiert. Es wurden eine konkrete Aufgabenstellung, abgestufte Hilfestellungen sowie quantitative und qualitative Messkriterien entwickelt.Das Ziel der vorliegenden Masterarbeit ist die empirische Evaluation der Screening-Aufgabe «Terminvereinbarung» in der Praxis. Es wird untersucht, ob die Screening-Aufgabe «Terminvereinbarung» für in der Praxis tätige Logopäd:innen verständlich und anwendbar ist. Die Bewertungen und Rückmeldungen der Logopäd:innen aus der Praxis werden durch qualitative Leitfadeninterviews erhoben und mittels inhaltlich strukturierender qualitativer Inhaltsanalyse ausgewertet. Die Ergebnisse der Untersuchung schätzen die Praktikabilität der ScreeningAufgabe «Terminvereinbarung» ein, zeigen ihre Stärken und Schwächen auf und weisen auf Anpassungswünsche hin.Die Screening-Aufgabe «Terminvereinbarung» wird von den sechs befragten Logopädinnen in der Praxis als verständlich und benutzerfreundlich eingeschätzt. Besonders positiv bewerten sie die Alltagsnähe und -relevanz der Aufgabe sowie die Möglichkeit, aktivitätsorientierte Therapieinhalte abzuleiten. Limitationen werden beim geringen Umfang der Aufgabe und bei den Aussagen auf sprachlich-funktioneller Ebene identifiziert. Dennoch können sich alle befragten Logopädinnen eine zukünftige Nutzung der Screening-Aufgabe «Terminvereinbarung» mit nur kleinen Anpassungen vorstellen.
Coherent coupled qubits for quantum annealing
Creators: name: Weber, Steven J.
name: Samach, Gabriel O.
name: Hover, David
name: Gustavsson, Simon
name: Kim, David K.
name: Melville, Alexander
name: Rosenberg, Danna
name: Sears, Adam P.
name: Yan, Fei
name: Yoder, Jonilyn L.
name: Oliver, William D.
name: Kerman, Andrew J.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Quantum annealing is an optimization technique which potentially leverages quantum tunneling to enhance computational performance. Existing quantum annealers use superconducting flux qubits with short coherence times, limited primarily by the use of large persistent currents $I_\mathrm{p}$. Here, we examine an alternative approach, using qubits with smaller $I_\mathrm{p}$ and longer coherence times. We demonstrate tunable coupling, a basic building block for quantum annealing, between two flux qubits with small ($\sim 50~\mathrm{nA}$) persistent currents. Furthermore, we characterize qubit coherence as a function of coupler setting and investigate the effect of flux noise in the coupler loop on qubit coherence. Our results provide insight into the available design space for next-generation quantum annealers with improved coherence.
On the occurrence of gauge-dependent secularities in nonlinear gravitational waves
Creators: name: Briscese, Fabio
name: Santini, Paolo Maria
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: We study the plane (not necessarily monochromatic) gravitational waves at nonlinear quadratic order on a flat background in vacuum. We show that, in the harmonic gauge, the nonlinear waves are unstable. We argue that, at this order, this instability can not be eliminated by means of a multiscale approach, i.e. introducing suitable long variables, as it is often the case when secularities appear in a perturbative scheme. However, this is a non-physical and gauge-dependent effect that disappears in a suitable system of coordinates. In facts, we show that in a specific gauge such instability does not occur, and that it is possible to solve exactly the second order nonlinear equations of gravitational waves. Incidentally, we note that this gauge coincides with the one used by Belinski and Zakharov to find exact solitonic solutions of Einstein's equations, that is to an exactly integrable case, and this fact makes our second order nonlinear solutions less interesting. However, the important warning is that one must be aware of the existence of the instability reported in this paper, when studying nonlinear gravitational waves in the harmonic gauge.
Updated Constraints on the Dark Matter Interpretation of CDMS-II-Si Data
Creators: name: Witte, Samuel J.
name: Gelmini, Graciela B.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present an updated halo-dependent and halo-independent analysis of viable light WIMP dark matter candidates which could account for the excess observed in CDMS-II-Si. We include recent constraints from LUX, PandaX-II, and PICO-60, as well as projected sensitivities for XENON1T, SuperCDMS SNOLAB, LZ, DARWIN, DarkSide-20k, and PICO-250, on candidates with spin-independent isospin conserving and isospin-violating interactions, and either elastic or exothermic scattering. We show that there exist dark matter candidates which can explain the CDMS-II-Si data and remain very marginally consistent with the null results of all current experiments, however such models are highly tuned, making a dark matter interpretation of CDMS-II-Si very unlikely. We find that these models can only be ruled out in the future by an experiment comparable to LZ or PICO-250.
description: v2: Published version. Figure 7 added and text modified, conclusions unchanged. v1: 18 pages, 6 figures
On calculation of RKKY range function in one dimension
Creators: name: Rusin, Tomasz M.
name: Zawadzki, Wlodek
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The effect of strong singularity in the calculation of range function for the RKKY interaction in 1D electron gas is discussed. The method of handling this singularity is presented. A possible way of avoiding the singularity in the Ruderman-Kittel perturbation theory in 1D is described.
description: 6 pages, 5 figures, some text added, accepted to: Journal of Magnetism and Magnetic Materials
An extensive VLT/X-Shooter library of photospheric templates of pre-main sequence stars
Creators: name: Manara, C. F.
name: Frasca, A.
name: Alcala, J. M.
name: Natta, A.
name: Stelzer, B.
name: Testi, L.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Studies of the formation and evolution of young stars and their disks rely on the knowledge of the stellar parameters of the young stars. The derivation of these parameters is commonly based on comparison with photospheric template spectra. Furthermore, chromospheric emission in young active stars impacts the measurement of mass accretion rates, a key quantity to study disk evolution. Here we derive stellar properties of low-mass pre-main sequence stars without disks, which represent ideal photospheric templates for studies of young stars. We also use these spectra to constrain the impact of chromospheric emission on the measurements of mass accretion rates. The spectra in reduced, flux-calibrated, and corrected for telluric absorption form are made available to the community. We derive the spectral type for our targets by analyzing the photospheric molecular features present in their VLT/X-Shooter spectra by means of spectral indices and comparison of the relative strength of photospheric absorption features. We also measure effective temperature, gravity, projected rotational velocity, and radial velocity from our spectra by fitting them with synthetic spectra with the ROTFIT tool. The targets have negligible extinction and spectral type from G5 to M8. We perform synthetic photometry on the spectra to derive the typical colors of young stars in different filters. We measure the luminosity of the emission lines present in the spectra and estimate the noise due to chromospheric emission in the measurements of accretion luminosity in accreting stars. We provide a calibration of the photospheric colors of young PMS stars as a function of their spectral type in a set of standard broad-band optical and near-infrared filters. For stars with masses of ~ 1.5Msun and ages of ~1-5 Myr, the chromospheric noise converts to a limit of measurable mass accretion rates of ~ 3x10^-10 Msun/yr.
description: Accepted for publication on Astronomy & Astrophysics. The spectra of the photospheric templates will be uploaded to Vizier, but are already available on request. Abstract shortened for arxiv constraints. Language edited version
Improved bounds on quantum uncommon information
Creators: name: Lee, Yonghae
name: Bae, Joonwoo
name: Yamasaki, Hayata
name: Lee, Soojoon
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In classical information theory, channel capacity quantifies the maximum number of messages that can be reliably transmitted using shared information. An equivalent concept, termed uncommon information, represents the number of messages required to be exchanged to completely share all information in common. However, this equivalence does not extend to quantum information theory. Specifically, quantum uncommon information is operationally defined as the minimal amount of entanglement required for the quantum communication task of quantum state exchange, where two parties exchange quantum states to share all quantum messages in common. Currently, an analytical closed-form expression for the quantum uncommon information remains undetermined. In this work, by investigating underlying characterization of the quantum uncommon information, we derive improved bounds on it. To obtain these bounds, we develop a subspace exchange strategy that leverages a common subspace of two parties to identify the unnecessary qubits for exchange. We also consider a referee-assisted exchange, wherein a referee aids two parties in efficiently performing the quantum state exchange. Our bounds provide more precise estimations for the quantum uncommon information. Furthermore, we demonstrate that the subspace technique is a versatile tool for characterizing uncommon information not only in the bipartite scenario but also in various multi-partite ones.
description: 24 pages, 7 figures, typos were corrected and readability was improved
News from the User’s Perspective: With Naivety to Validity
Creators: name: Schneiders, Pascal
Publisher: name: Taylor & Francis
Year: 2023
Subjects: Biochemistry
Cancer
Science Policy

description: In journalism studies, news is still closely tied to journalistic institutions. However, the rise of digital platforms as gateways to news, catalyzing processes of dedifferentiation, challenges established news definitions. This makes a dedication to the audience understanding of news all the more urgent. That is, in order to measure news in everyday life contexts as validly as possible, scientific operationalization and lay definition of news should be as close as possible.Accordingly, drawing on 26 semi-structured in-depth interviews with subjects diverse in age, gender, and education, this article explores what constitutes news from user’s perspectives, and to this end, differentiates between news originator, content, style, channel, and function. Interviews were complemented by card-laying tasks with participants being asked to decide whether or not different actors, actants, headlines, and social media posts were news (dimensions). Findings show that people have a heterogeneous understanding of news originators and channels, but their associations of news content and style are informed by traditional journalistic norms. Thereby, audiences emphasize neutrality and news as output of selfless activity. The article concludes that an institutionally shaped definition of news does not capture the term’s extension in people’s everyday exposure any more. Finally, methodological-practical implications are discussed.
Alternative Media Vary Between Mild Distortion and Extreme Misinformation: Steps Toward a Typology
Creators: name: Staender, Anna
name: Humprecht, Edda
name: Esser, Frank
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Space Science
subject: Medicine
subject: Biotechnology
subject: Evolutionary Biology
subject: FOS: Biological sciences
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified
subject: Cancer
subject: Science Policy

description: Social media has faced criticism for promoting misinformation. The role of alternative media in spreading misinformation, however, remains uncertain. We examined 1661 Facebook posts from 25 most popular alternative media outlets during the Covid-19 pandemic in five countries (France, Germany, Switzerland, the UK, and the US). Our codebook covered a wide range of categories, from mild misleading content to blatant misinformation. Through cluster analysis, we identified four reporting types in alternative media: Light distortion, heavy distortion, ideological misinformation, and extreme misinformation. Light and heavy distortion were most prevalent in popular alternative media, while ideological and extreme misinformation had smaller but more engaged audiences. In summary, alternative media found more success on Facebook with content categorized as light and heavy distortion. This typology recognizes complexity in misinformation and alternative media research, while simultaneously reduces complexity to contribute to comparative studies in the future.
How Propaganda Works in the Digital Era: Soft News as a Gateway
Creators: name: Zhu, Yuner
name: Fu, King-wa
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Evolutionary Biology
subject: FOS: Biological sciences
subject: Environmental Sciences not elsewhere classified
subject: Biological Sciences not elsewhere classified
subject: Cancer
subject: Science Policy
subject: Mental Health

description: Digital technology can empower citizen journalism as well as state media in authoritarian regimes. China’s propaganda apparatus has undertaken a series of transformations to adapt itself to the changing media environment. This study investigates this adaptive process by drawing on over five million Weibo posts created by 103 newspapers between 2012 and 2019. Results show that through the digital transformation, newspapers are deliberately distancing themselves from their Orwellian past of abstract dogmatism to openly embrace infotainment. A soft-news-centered production model has emerged as the new journalistic paradigm on social media. Not only commercialized outlets but also mouthpiece newspapers produce more soft news than hard news. Regression results further substantiate that soft news is a gateway to propaganda, whose popularity can spill over into propaganda news. For every 100% increase in soft news popularity, propaganda popularity will rise by 38.5% in the following month. News outlets that have garnered attention to soft news can transfer that attention to their subsequent propaganda. These results illuminate how propaganda works in the digital realm, how authoritarian propaganda could be enhanced by infotainment, and why a less political platform could be more susceptible to political intervention.
CMB constraints on primordial black hole dark matter
Creators: name: Aloni, Daniel
name: Blum, Kfir
name: Flauger, Raphael
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We revisit cosmic microwave background (CMB) constraints on primordial black hole dark matter. Spectral distortion limits from COBE/FIRAS do not impose a relevant constraint. Planck CMB anisotropy power spectra imply that primordial black holes with $m_{BH}\gtrsim 5~M_{\odot}$ are disfavored. However, this is susceptible to sizeable uncertainties due to the treatment of the black hole accretion process. These constraints are weaker than those quoted in earlier literature for the same observables.
description: 4 pages. v2: changed treatment of statistical averaging of relative bulk motion between pBHs and baryonic plasma
A theoretical study of the g-factor of the 6s6p 3P0 state of mercury
Creators: name: Porsev, S. G.
name: Safronova, U. I.
name: Safronova, M. S.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We calculate the g-factor of the 6s6p 3P0 state of 199 and 201 mercury isotopes using a relativistic high-precision all-order method that combines the configuration interaction and the coupled-cluster approaches. Our values $g(199Hg) = -0.9485(49)*10^{-3}$ and $g(201Hg) = -0.3504(18)*10^{-3}$ are in agreement with the experimental measurements within the 0.5% theoretical uncertainty. We also calculate the hyperfine quenching rate of the 6s6p 3P0 state in 199Hg and 201Hg and determine its lifetime to be 1.3 and 1.9 s, respectively.
description: 6 pages, the text was slightly revised and noted misprints were corrected
MOVER tests for non-inferiority of the difference between two binary-outcome treatments in the matched-pairs design
Creators: name: Xiu, Liangchang
name: Xie, Linlin
name: Yan, Haiyi
name: Wu, Chunxin
name: Liu, Huansheng
name: Chen, Chao
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Medicine
subject: Neuroscience
subject: Pharmacology
subject: Biotechnology
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified
subject: Mathematical Sciences not elsewhere classified
subject: Science Policy

description: A non-inferiority trial is usually conducted to investigate whether a new drug/treatment is no worse than a reference drug/treatment by a small, pre-specified, non-inferiority margin. This study aimed to assess the non-inferiority of the difference between two binary-outcome treatments in a matched-pairs design based on the method of variance of estimates recovery (MOVER). The processes for estimating the confidence interval of a single proportion included in the MOVER are the Wilson score interval, Agresti – Coull interval, Jeffreys interval, modified Jeffreys interval, score method with continuity correction, and arcsin interval. The performance of the six MOVER tests, the fiducial test, and the restricted maximum likelihood estimation test were evaluated by comparing their type I error rates and power at different pre-assigned levels and with varying combinations of parameters. The evaluation results showed that the modified Jeffreys MOVER test can be a competitive alternative to the other recommended tests. It can control type I errors well, and its power is not inferior to other methods. The proposed tests were illustrated with three real-world examples.
Martin Le Franc, Agreste otium. De bono mortis. Hrsg. u. bearb. v. Raphael Schwitter. (Monumenta Germaniae Historica. Quellen zur Geistesgeschichte des Mittelalters, Bd. 30.) Wiesbaden, Harrassowitz 2018
Creators: name: Woelki, Thomas
Publisher: name: Humboldt-Universität zu Berlin
Year: 2020
Subjects: subject: 940 Geschichte Europas

description: Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
Local correlation functions of arbitrary order for the Falicov-Kimball model
Creators: name: Ribic, Tin
name: Rohringer, Georg
name: Held, Karsten
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Local n-particle vertex functions represent the crucial ingredient for all diagrammatic extensions of dynamical mean field theory (DMFT). Hitherto their application has been restricted -with a few exceptions- to the n=2-particle vertex while higher-order vertices have been neglected. In this paper we derive a general analytical expression for the n-particle (one-particle reducible) vertex of the Falicov-Kimball model (FKM). We observe that the magnitude of such vertex functions itself strongly increases with the particle-number n. On the other hand, their effect on generic Feynman diagrams remains rather moderate due to the damping effect of the Green's functions present in such diagrams. Nevertheless, they yield important contributions to the self-energy corrections calculated in diagrammatic extensions of DMFT as we explicitly demonstrate using the example of dual fermion (DF) calculations for the two-dimensional FKM at quarter filling of stationary f-electrons where corrections to the self-energy obtained from the three-particle vertex are indeed comparable in magnitude to corresponding corrections stemming from the two-particle vertex.
description: 12 pages, 10 figures
Optimized evolution of networks for principal eigenvector localization
Creators: name: Pradhan, Priodyuti
name: Yadav, Alok
name: Dwivedi, Sanjiv K.
name: Jalan, Sarika
Publisher: name: arXiv
Year: 2017
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: Network science is increasingly being developed to get new insights about behavior and properties of complex systems represented in terms of nodes and interactions. One useful approach is investigating localization properties of eigenvectors having diverse applications including disease-spreading phenomena in underlying networks. In this work, we evolve an initial random network with an edge rewiring optimization technique considering the inverse participation ratio as a fitness function. The evolution process yields a network having localized principal eigenvector. We analyze various properties of the optimized networks and those obtained at the intermediate stage. Our investigations reveal the existence of few special structural features of such optimized networks including the presence of a set of edges which are necessary for the localization, and rewiring only one of them leads to a complete delocalization of the principal eigenvector. Our investigation reveals that PEV localization is not a consequence of a single network property, and preferably requires co-existence of various distinct structural as well as spectral features.
description: 7 pages, and 8 figures
Dark-ages reionization and galaxy formation simulation - IX. Economics of reionizing galaxies
Creators: name: Duffy, Alan R.
name: Mutch, Simon J.
name: Poole, Gregory B.
name: Geil, Paul M.
name: Kim, Han-Seek
name: Mesinger, Andrei
name: Wyithe, J. Stuart B.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Using a series of high-resolution hydrodynamical simulations we show that during the rapid growth of high-redshift (z > 5) galaxies, reserves of molecular gas are consumed over a time-scale of 300Myr, almost independent of feedback scheme. We find that there exists no such simple relation for the total gas fractions of these galaxies, with little correlation between gas fractions and specific star formation rates. The bottleneck or limiting factor in the growth of early galaxies is in converting infalling gas to cold star-forming gas. Thus, we find that the majority of high redshift dwarf galaxies are effectively in recession, with demand (of star formation) never rising to meet supply (of gas), irrespective of the baryonic feedback physics modelled. We conclude that the basic assumption of self-regulation in galaxies - that they can adjust total gas consumption within a Hubble time - does not apply for the dwarf galaxies thought to be responsible for providing most UV photons to reionize the high redshift Universe. We demonstrate how this rapid molecular time-scale improves agreement between semi-analytic model predictions of the early Universe and observed stellar mass functions.
description: 17 pages, 27 figures, accepted for publication in MNRAS, minor updates to align with final published version
Inversion of the exciton built-in dipole moment in In(Ga)As quantum dots via nonlinear piezoelectric effect
Creators: name: Aberl, Johannes
name: Klenovský, Petr
name: Wildmann, Johannes S.
name: Martín-Sánchez, Javier
name: Fromherz, Thomas
name: Zallo, Eugenio
name: Humlíček, Josef
name: Rastelli, Armando
name: Trotta, Rinaldo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We show that anisotropic biaxial stress can be used to tune the built-in dipole moment of excitons confined in In(Ga)As quantum dots up to complete erasure of its magnitude and inversion of its sign. We demonstrate that this phenomenon is due to piezoelectricity. We present a model to calculate the applied stress, taking advantage of the so-called piezotronic effect, which produces significant changes in the current-voltage characteristics of the strained diode-membranes containing the quantum dots. Finally, self-consistent k.p calculations reveal that the experimental findings can be only accounted for by the nonlinear piezoelectric effect, whose importance in quantum dot physics has been theoretically recognized although it has proven difficult to single out experimentally.
description: 6 pages, 4 figures
Persistent Black Holes in Bouncing Cosmologies
Creators: name: Clifton, Timothy
name: Carr, Bernard
name: Coley, Alan
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: In this paper we explore the idea that black holes can persist in a universe that collapses to a big crunch and then bounces into a new phase of expansion. We use a scalar field to model the matter content of such a universe {near the time} of the bounce, and look for solutions that represent a network of black holes within a dynamical cosmology. We find exact solutions to Einstein's constraint equations that provide the geometry of space at the minimum of expansion and that can be used as initial data for the evolution of hyperspherical cosmologies. These solutions illustrate that there exist models in which multiple distinct black holes can persist through a bounce, and allow for concrete computations of quantities such as the black hole filling factor. We then consider solutions in flat cosmologies, as well as in higher-dimensional spaces (with up to nine spatial dimensions). We derive conditions for the black holes to remain distinct (i.e. avoid merging) and hence persist into the new expansion phase. Some potentially interesting consequences of these models are also discussed.
description: 37 pages, 16 figures
PowerShap: A Power-Full Shapley Feature Selection Method
Creators: name: Verhaeghe, Jarne
name: Van Der Donckt, Jeroen
name: Ongenae, Femke
name: Van Hoecke, Sofie
Publisher: name: Zenodo
Year: 2022

description: Feature selection is a crucial step in developing robust and powerful machine learning models. Feature selection techniques can be divided into two categories: filter and wrapper methods. While wrapper methods commonly result in strong predictive performances, they suffer from a large computational complexity and therefore take a significant amount of time to complete, especially when dealing with high-dimensional feature sets. Alternatively, filter methods are considerably faster, but suffer from several other disadvantages, such as (i) requiring a threshold value, (ii) many filter methods not taking into account intercorrelation between features, and (iii) ignoring feature interactions with the model. To this end, we present PowerShap, a novel wrapper feature selection method, which leverages statistical hypothesis testing and power calculations in combination with Shapley values for quick and intuitive feature selection. PowerShap is built on the core assumption that an informative feature will have a larger impact on the prediction compared to a known random feature. Benchmarks and simulations show that PowerShap outperforms other filter methods with predictive performances on par with wrapper methods while being significantly faster, often even reaching half or a third of the execution time. As such, PowerShap provides a competitive and quick algorithm that can be used by various models in different domains. Furthermore, PowerShap is implemented as a plug-and-play and open-source sklearn component, enabling easy integration in conventional data science pipelines. User experience is even further enhanced by also providing an automatic mode that automatically tunes the hyper-parameters of the PowerShap algorithm, allowing to use the algorithm without any configuration needed.
Orbital order and fluctuations in the two-leg ladder materials BaFe$_2X_3$ ($X$ = S and Se) and CsFe$_2$Se$_3$
Creators: name: Takubo, Kou
name: Yokoyama, Yuichi
name: Wadati, Hiroki
name: Iwasaki, Shun
name: Mizokawa, Takashi
name: Boyko, Teak
name: Sutarto, Ronny
name: He, Feizhou
name: Hashizume, Kazuki
name: Imaizumi, Satoshi
name: Aoyama, Takuya
name: Imai, Yoshinori
name: Ohgushi, Kenya
Publisher: name: arXiv
Year: 2017
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The electronic structure of BaFe$_2X_3$ ($X$ = S and Se) and CsFe$_2$Se$_3$ in which two-leg ladders are formed by the Fe sites are studied by means of x-ray absorption and resonant inelastic x-ray scattering spectroscopy. The x-ray absorption spectra at the Fe L edges for BaFe$_2X_3$ exhibit two components, indicating that itinerant and localized Fe 3$d$ sites coexist. Substantial x-ray linear dichroism (XLD) is observed in polarization dependent spectra, indicating the existence of orbital order or fluctuation in the Fe-ladder even above the Néel temperature $T_N$. Direct exchange interaction along the legs of the Fe-ladder stabilizes the orbital and antiferromagnetic orders in BaFe$_2$S$_3$, while the ferromagnetic molecular orbitals are realized between the rungs in CsFe$_2$Se$_3$.
description: 7 pages,5 figures
Inspiral-inherited ringdown tails
Creators: name: De Amicis, Marina
name: Albanesi, Simone
name: Carullo, Gregorio
Publisher: name: arXiv
Year: 2024
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the late-time relaxation of a perturbed Schwarzschild black hole, driven by a source term representing an infalling particle in generic orbits. We consider quasi-circular and eccentric binaries, dynamical captures and radial infalls, with orbital dynamics driven by an highly accurate analytical radiation reaction. After reviewing the description of the late-time behaviour as an integral over the whole inspiral history, we derive an analytical expression exactly reproducing the slow relaxation observed in our numerical evolutions, obtained with a hyperboloidal compactified grid, for a given particle trajectory. We find this signal to be a superposition of an infinite number of power-laws, the slowest decaying term being Price's law. Next, we use our model to explain the several orders-of-magnitude enhancement of tail terms for binaries in non-circular orbits, shedding light on recent unexpected results obtained in numerical evolutions. In particular, we show the dominant terms controlling the enhancement to be activated when the particle is far from the BH, with small tangential and radial velocities soon before the plunge. As we corroborate with semi-analytical calculations, this implies that for large eccentricities the tail amplitude can be correctly extracted even when starting to evolve only from the last apastron before merger. We discuss the implications of these findings on the extraction of late-time tail terms in non-linear evolutions, and possible observational consequences. We also briefly comment on the scattering scenario, and on the connection with the soft graviton theorem.
description: 28 pages, 18 figures
A hybrid numerical method for elastic wave propagation in discontinuous media with complex geometry
Creators: name: Granath, Andreas
name: Wang, Siyang
Publisher: name: arXiv
Year: 2024
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 65M06, 65M60, 65M12

description: We develop a high order accurate numerical method for solving the elastic wave equation in second-order form. We hybridize the computationally efficient Cartesian grid formulation of finite differences with geometrically flexible discontinuous Galerkin methods on unstructured grids by a penalty based technique. At the interface between the two methods, we construct projection operators for the pointwise finite difference solutions and discontinuous Galerkin solutions based on piecewise polynomials. In addition, we optimize the projection operators for both accuracy and spectrum. We prove that the overall discretization conserves a discrete energy, and verify optimal convergence in numerical experiments.
General Scattering Characteristics of Resonant Core-Shell Spheres
Creators: name: Tzarouchis, Dimitrios C.
name: Sihvola, Ari
Publisher: name: arXiv
Year: 2017
Subjects: subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: This article presents and discusses the general features and aspects regarding the electromagnetic scattering by a small core-shell plasmonic sphere. First, the thickness effects on the plasmonic resonances are presented in the electrostatic (Rayleigh) limit, utilizing the MacLaurin expansion of the Mie coefficients of hollow scatterers. Several aspects regarding the core effects are given, illustrating the enabling mechanisms and peculiarities of its resonant scattering response on it electrostatic limit. The electrodynamic aspects of the scattering process are revealed through the newly introduced Padé expansion of the Mie coefficients. Additionally we expose how the core material affects the dynamic mechanisms, such as the dynamic depolarization and radiative damping. The described method can be expanded for other type of resonances and canonical shapes, while the general characteristics presented here are expected to stimulate further studies regarding the functionalities of the core-shell scatterers.
description: 8 pages, 3 figures, under review to IEEE TAP
title: Green Hydrogen for the Steelmaking Industry
Creators: name: Rieger, Emile Claude Ignaz
Publisher: name: TU Wien
Year: 2023
Subjects: subject: green hydrogen
subject: steelmaking industry
subject: offshore wind energy
subject: technology
subject: policy making

description: This work studies the production of green hydrogen for the steelmaking industry using offshore wind energy. It reviews the main existing and developing technology for the production, storage, transport and use of green hydrogen. It also examines the history and current state of policy making on green hydrogen. It the proposes a possible configuration for the green hydrogen value chain from its production to its end-use in the steelmaking industry. Finally, it defines the main challenges observed in such a configuration and makes recommendations for future policy making.
Harmonic analysis for real spherical spaces
Creators: name: Krötz, Bernhard
name: Schlichtkrull, Henrik
Publisher: name: arXiv
Year: 2016
Subjects: subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: We give an introduction to basic harmonic analysis and representation theory for homogeneous spaces $Z=G/H$ attached to a real reductive Lie group $G$. A special emphasis is made to the case where $Z$ is real spherical.
description: Shortened title, typos fixed, more details on dual smooth Frobenius reciprocity (now Lemma 6.6). 38 pages, lecture notes for the Sanya meeting on spherical varieties. To appear in Acta Math. Sinica
Thermal activation of thin-shells in anti-de Sitter black hole spacetime
Creators: name: Chen, Pisin
name: Domènech, Guillem
name: Sasaki, Misao
name: Yeom, Dong-han
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate thermal activation of thin-shells around anti-de Sitter black holes. Under the thin-shell approximation, we extensively study the parameter region that allows a bubble nucleation bounded by a thin-shell out of a thermal bath. We show that in general if one fixes the temperature outside the shell, one needs to consider the presence of a conical deficit inside the shell in the Euclidean manifold, due to the lack of solutions with a smooth manifold. We show that for a given set of theoretical parameters, i.e., vacuum and shell energy density, there is a finite range of black hole masses that allow this transition. Most interestingly, one of them describes the complete evaporation of the initial black hole.
description: published version
Laser-induced Translative Hydrodynamic Mass Snapshots: mapping at nanoscale
Creators: name: Wang, X. W.
name: Kuchmizhak, A. A.
name: Li, X.
name: Juodkazis, S.
name: Vitrik, O. B.
name: Kulchin, Yu. N.
name: Zhakhovsky, V. V.
name: Danilov, P. A.
name: Ionin, A. A.
name: Kudryashov, S. I.
name: Rudenko, A. A.
name: Inogamov, N. A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Nanoscale thermally assisted hydrodynamic melt perturbations induced by ultrafast laser energy deposition in noble-metal films produce irreversible nanoscale translative mass redistributions and results in formation of radially-symmetric frozen surface structures. We demonstrate that the final three-dimensional (3D) shape of the surface structures formed after resolidification of the molten part of the film is shown to be governed by incident laser fluence and, more importantly, predicted theoretically via molecular dynamics modeling. Considering the underlying physical processes associated with laser-induced energy absorption, electron-ion energy exchange, acoustic relaxation and hydrodynamic flows, the theoretical approach separating slow and fast physical processes and combining hybrid analytical two-temperature calculations, scalable molecular-dynamics simulations, and a semi-analytical thin-shell model was shown to provide accurate prediction of the final nanoscale solidified morphologies, fully consistent with direct electron-microscopy visualization of nanoscale focused ion-beam cuts of the surface structures produced at different incident laser fluences. Finally, these results are in reasonable quantitative agreement with mass distribution profiles across the surface nanostructures, provided by their noninvasive and non-destructive nanoscale characterization based on energy-dispersive x-ray fluorescence spectroscopy, operating at variable electron-beam energies.
description: 12 pages, 5 figures
Modeling the Efficiency and Effective Temperature of Bacterial Heat Engines
Creators: name: Wiese, Roland
name: Kroy, Klaus
name: Holubec, Viktor
Publisher: name: arXiv
Year: 2024
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We present a Brownian dynamics simulation of the bacterial Stirling engine studied by Krishnamurthy et al., Nat. Phys. 12, 1134 (2016). In their experimental setup, an overdamped colloid in an optical trap with time-modulated stiffness interacts with a bacterial bath that we represent by an ensemble of overdamped active particles. In the parameter regime of the experiment the thermodynamic performance is governed by an effective temperature and can be parametrized analytically by active Brownian particle models. We quantitatively reproduce the efficiencies reported for the experiments under the assumption that energy exchange with the bath during isochores of the cycle is entirely recuperated and in agreement with the second law.
description: 12 pages, 7 figures
Elliptic Flow in Small Systems due to Elliptic Gluon Distributions?
Creators: name: Hagiwara, Yoshikazu
name: Hatta, Yoshitaka
name: Xiao, Bo-Wen
name: Yuan, Feng
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We investigate the contributions from the so-called elliptic gluon Wigner distributions to the rapidity and azimuthal correlations of particles produced in high energy $pA$ collisions by applying the double parton scattering mechanism. We compute the `elliptic flow' parameter $v_2$ as a function of the transverse momentum and rapidity, and find qualitative agreement with experimental observations. This shall encourage further developments with more rigorous studies of the elliptic gluon distributions and their applications in hard scattering processes in $pp$ and $pA$ collisions.
description: 8 pages, 8 figures; v2 discussion in the numerical section modified, results unchanged, to appear in Phys. Lett. B; v3 one reference added
Diversity of fish and macrobenthos at the coastal area of Tanjung Kidurong Power Plant (TKPP), Sarawak, Malaysia
Creators: name: Al-Asif, Abdulla-
Publisher: name: figshare
Year: 2022
Subjects: Community ecology (excl. invasive species ecology)
Ecology not elsewhere classified
Marine and estuarine ecology (incl. marine ichthyology)
Population ecology
Invertebrate biology
Vertebrate biology
Zoology not elsewhere classified

description: The regular assessment of faunal diversity near the energy power plant has gained the interest of many researchers. The activity and the effluent discharged from the power plant have remarkably stressed the adjacent assemblage of the alpha biotic community surrounding the power plant. Hence, this study aimed to assess the alpha faunal diversity of fishes and benthos in the bordering areas of Tanjung Kidurong Combined Cycle Power Plant (TKCCP), Bintulu Sarawak. The investigation was conducted in the coastal area from 2019 to 2020. Different ecological indices such as the evenness index, Margalef richness, and Shannon-Weiner diversity index were implemented, along with the cluster analysis of other stations. A number of 141 fish individuals were recorded, containing 40 species of 19 families. In addition, 13182 individuals of benthos communities from six classes and 37 species were identified. A percentage of 78 comprised fishes, while 22% were identified as crustaceans. Among the benthos addressed, Foraminifera was the major group (74%), followed by bivalve (10%) and Scaphopoda (7%). Compared to SEB2, 3 & 4, SEB1, the nearest to the power plant, recorded the highest richness, number of species, and diversity indexes. Cluster analysis, PCA, and nMDS analysis suggested that SEB2, SEB3, SEB4 had similar biodiversity compositions. The study of benthos indicates that SEB1 possesses a distinguished value of diversity and evenness indexes. This study would provide future researchers with vital documentation to evaluate the impact of thermal discharge from the power plant on alpha biodiversity in Bintulu, Sarawak, Malaysia.