cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
SpaceInn hare-and-hounds exercise: Estimation of stellar properties using space-based asteroseismic data
Creators: name: Reese, D. R.
name: Chaplin, W. J.
name: Davies, G. R.
name: Miglio, A.
name: Antia, H. M.
name: Ball, W. H.
name: Basu, S.
name: Buldgen, G.
name: Christensen-Dalsgaard, J.
name: Coelho, H. R.
name: Hekker, S.
name: Houdek, G.
name: Lebreton, Y.
name: Mazumdar, A.
name: Metcalfe, T. S.
name: Aguirre, V. Silva
name: Stello, D.
name: Verma, K.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Context: Detailed oscillation spectra comprising individual frequencies for numerous solar-type stars and red giants are or will become available. These data can lead to a precise characterisation of stars. Aims: Our goal is to test and compare different methods for obtaining stellar properties from oscillation frequencies and spectroscopic constraints, in order to evaluate their accuracy and the reliability of the error bars. Methods: In the context of the SpaceInn network, we carried out a hare-and-hounds exercise in which one group produced "observed" oscillation spectra for 10 artificial solar-type stars, and various groups characterised these stars using either forward modelling or acoustic glitch signatures. Results: Results based on the forward modelling approach were accurate to 1.5 % (radius), 3.9 % (mass), 23 % (age), 1.5 % (surface gravity), and 1.8 % (mean density). For the two 1 Msun stellar targets, the accuracy on the age is better than 10 % thereby satisfying PLATO 2.0 requirements. The average accuracies for the acoustic radii of the base of the convection zone, the He II ionisation, and the Gamma_1 peak were 17 %, 2.4 %, and 1.9 %, respectively. Glitch fitting analysis seemed to be affected by aliasing problems for some of the targets. Conclusions: Forward modelling is the most accurate approach, but needs to be complemented by model-independent results from, e.g., glitch analysis. Furthermore, global optimisation algorithms provide more robust error bars.
description: 29 pages, 13 figures, 20 tables, accepted in A&A
Diffractive lensing of nano-Hertz gravitational waves emitted from supermassive binary black holes by intervening galaxies
Creators: name: Ma, Hao
name: Lu, Youjun
name: Chen, Zhiwei
name: Chen, Yunfeng
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Pulsar timing array (PTA) experiments are expected to detect nano-Hertz gravitational waves (GWs) emitted from individual inspiralling supermassive binary black holes (SMBBHs). The GW signals from a small fraction of these SMBBHs may be diffractively lensed by intervening galaxies. In this paper, we investigate the diffractive lensing effects on the continuous GW signals from the lensed SMBBHs and estimate the detectable number of such signals by PTAs, such as the Chinese PTA (CPTA) and the Square Kilometer Array (SKA) PTA. We find that the amplitude of the lensed GW signals may be only amplified by a factor of $\sim 1.01-1.14$ ($16\%-84\%$ range) and the phase of the signals may shift somewhat due to the lensing, significantly different from those strongly lensed high frequency GW signals from compact binary mergers in the geometric optics. We estimate that $\sim 0.01\%$ of all detected nano-Hertz GW signals from individual SMBBHs by future PTA experiments are lensed by foreground galaxies (i.e., up to $\sim 106$ for CPTA and up to $\sim 289$ for SKA-PTA). However, the lensed nano-Hertz GW signals are difficult to be distinguished from those without lensing by the PTA observations only. We further discuss the possibility about the identification of the lensed nano-Hertz GW signals from SMBBHs via the electromagnetic detection of their host galaxies or active galactic nuclei.
description: 12 pages, 8 figures, Accepted for publication in MNRAS
Spectroscopic study of Herbig Ae/Be stars in the Galactic Anti-center region from LAMOST DR5
Creators: name: Nidhi, S.
name: Mathew, Blesson
name: Shridharan, B.
name: Arun, R.
name: Anusha, R.
name: Kartha, Sreeja S.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We study a sample of 119 Herbig Ae/Be stars in the Galactic anti-center direction using the spectroscopic data from Large sky Area Multi-Object fiber Spectroscopic Telescope (LAMOST) survey program. Emission lines of hydrogen belonging to the Balmer and Paschen series, and metallic lines of species such as FeII, OI, CaII triplet are identified. A moderate correlation is observed between the emission strengths of H$α$ and FeII 5169 Å, suggesting a possible common emission region for FeII lines and one of the components of H$α$. We explored a technique for the extinction correction of the HAeBe stars using diffuse interstellar bands present in the spectrum. We estimated the stellar parameters such as age and mass of these HAeBe stars, which are found to be in the range 0.1 -- 10 Myr and 1.5 -- 10 $M_{\odot}$, respectively. We found that the mass accretion rate of the HAeBe stars in the Galactic anti-center direction follows the relation $\dot{M}_{acc}$ $\propto$ $M_{*}^{3.12^{+0.21}_{-0.34}}$, which is similar to the relation derived for HAeBe stars in other regions of the Galaxy. The mass accretion rate of HAeBe stars is found to have a functional form of $\dot{M}_{acc} \propto t^{-1.1 \pm 0.2}$ with age, in agreement with previous studies.
description: 18 pages, 11 figures, 3 tables, accepted for publication in MNRAS
Growth of Epitaxial Graphene: Theory and Experiment
Creators: name: Tetlow, H.
name: de Boer, J. Posthuma
name: Ford, I. J.
name: Vvedensky, D. D.
name: Coraux, J.
name: Kantorovich, L.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: A detailed review of the literature for the last 5-10 years on epitaxial growth of graphene is presented. Both experimental and theoretical aspects related to growth on transition metals and on silicon carbide are thoroughly reviewed. Thermodynamic and kinetic aspects of growth on all these materials, where possible, are discussed. To make this text useful for a wider audience, a range of important experimental techniques that have been used over the last decade to grow (e.g. CVD, TPG and segregation) and characterize (STM, LEEM, etc.) graphene are reviewed, and a critical survey of the most important theoretical techniques is given. Finally, we critically discuss various unsolved problems related to growth and its mechanism which we believe require proper attention in future research.
The key role of Lagrangian multiplier in mimetic gravitational theory in the frame of isotropic compact star
Creators: name: Nashed, G. G. L.
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Recently, the mimetic gravitational theory has gained much attention in the frame of cosmology as well as in the domain of astrophysics. In this study, we show that in the frame of mimetic gravitation theory we are not able to derive an isotropic model. As a result, our focus shifts towards combining mimetic gravitational theory with the Lagrangian multiplier. The field equations of a static isotropic gravitational system that controls the geometry and dynamics of star structure are studied in the frame of mimetic theory coupled with a Lagrangian multiplier using a non-linear equation of state. An energy density is assumed from where all the other unknowns are fixed and a new isotropic model is derived. The physical analysis of this model is studied from different viewpoints and consistent results compatible with a realistic isotropic star are investigated analytically and graphically. Ultimately, we demonstrate the stability of the model in question by employing the adiabatic index technique.
description: 12 pages 6 figures
Linear Versus Non-linear Supersymmetry, in General
Creators: name: Ferrara, Sergio
name: Kallosh, Renata
name: Van Proeyen, Antoine
name: Wrase, Timm
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study superconformal and supergravity models with constrained superfields. The underlying version of such models with all unconstrained superfields and linearly realized supersymmetry is presented here, in addition to the physical multiplets there are Lagrange multiplier (LM) superfields. Once the equations of motion for the LM superfields are solved, some of the physical superfields become constrained. The linear supersymmetry of the original models becomes non-linearly realized, its exact form can be deduced from the original linear supersymmetry. Known examples of constrained superfields are shown to require the following LM's: chiral superfields, linear superfields, general complex superfields, some of them are multiplets with a spin.
description: 24 p
Evidence for a Nonplanar Amplituhedron
Creators: name: Bern, Zvi
name: Herrmann, Enrico
name: Litsey, Sean
name: Stankowicz, James
name: Trnka, Jaroslav
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The scattering amplitudes of planar N = 4 super-Yang-Mills exhibit a number of remarkable analytic structures, including dual conformal symmetry and logarithmic singularities of integrands. The amplituhedron is a geometric construction of the integrand that incorporates these structures. This geometric construction further implies the amplitude is fully specified by constraining it to vanish on spurious residues. By writing the amplitude in a dlog basis, we provide nontrivial evidence that these analytic properties and "zero conditions" carry over into the nonplanar sector. This suggests that the concept of the amplituhedron can be extended to the the nonplanar sector of N = 4 super-Yang-Mills theory.
description: 44 pages, 9 figures
Accreting Black Holes Skewing and Bending the Optical Emission from Massive Wolf-Rayet Companions -- A Case Study of IC10 X-1
Creators: name: Bhattacharya, Sayantan
name: Christodoulou, Dimitris M.
name: Chene, Andre-Nicolas
name: Laycock, Silas G. T.
name: Binder, Breanna A.
name: Kazanas, Demosthenes
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present a statistical analysis of the He ii 4686 emission line in the spectra of the black hole and Wolf-Rayet (WR) star of the high-mass X-ray binary IC10 X-1. This line is visibly skewed, and the third moment (skewness) varies with the binary's orbital phase. We describe a new method of extracting such weak/faint features lying barely above a noisy continuum. Using the moments of these features, we have been able to decompose these skewed lines into two symmetric Gaussian profiles as a function of the orbital phase. The astrophysical implications of this decomposition are significant due to the complex nature of wind-accretion stream interactions in such binary systems. Previous studies have already shown a 0.25 phase lag in the radial velocity curve of the star and the X-ray eclipse, which indicates that the He ii emitters might be in the stellar wind, hence not tracing the star's orbital motion. Results from this work further suggest the existence of two separate emitting regions, one in the stellar wind in the shadow of the WR star, and another in the accretion stream that impacts the black hole's outer accretion disk; and the observed skewed He ii lines can be reproduced by superposition of the two corresponding time-dependent Gaussian emission profiles.
description: 13 pages, 5 figures, accepted for publication in MNRAS Journal
Future Collider Signatures of the Possible 750 GeV State
Creators: name: Djouadi, Abdelhak
name: Ellis, John
name: Godbole, Rohini
name: Quevillon, Jérémie
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: If the recent indications of a possible state $Φ$ with mass $\sim 750$ GeV decaying into two photons reported by ATLAS and CMS in LHC collisions at 13 TeV were to become confirmed, the prospects for future collider physics at the LHC and beyond would be affected radically, as we explore in this paper. Even minimal scenarios for the $Φ$ resonance and its $γγ$ decays require additional particles with masses $\gtrsim \frac12 m_Φ$. We consider here two benchmark scenarios that exemplify the range of possibilities: one in which $Φ$ is a singlet scalar or pseudoscalar boson whose production and $γγ$ decays are due to loops of coloured and charged fermions, and another benchmark scenario in which $Φ$ is a superposition of (nearly) degenerate CP-even and CP-odd Higgs bosons in a (possibly supersymmetric) two-Higgs doublet model also with additional fermions to account for the $γγ$ decay rate. We explore the implications of these benchmark scenarios for the production of $Φ$ and its new partners at colliders in future runs of the LHC and beyond, at higher-energy $pp$ colliders and at $e^+ e^-$ and $γγ$ colliders, with emphasis on the bosonic partners expected in the doublet scenario and the fermionic partners expected in both scenarios.
description: 52 pages, 24 figures, v2 corrects two plots and some typos, and contains a new section on production in electron-positron collisions as well as additional references
Photoproduction of the $f_1(1285)$ Meson
Creators: name: Dickson, R.
name: Schumacher, R. A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The $f_1(1285)$ meson with mass $1281.0 \pm 0.8$ MeV/$c^2$ and width $18.4 \pm 1.4$ MeV (FWHM) was measured for the first time in photoproduction from a proton target using CLAS at Jefferson Lab. Differential cross sections were obtained via the $ηπ^{+}π^{-}$, $K^+\bar{K}^0π^-$, and $K^-K^0π^+$ decay channels from threshold up to a center-of-mass energy of 2.8 GeV. The mass, width, and an amplitude analysis of the $ηπ^{+}π^{-}$ final-state Dalitz distribution are consistent with the axial-vector $J^P=1^+$ $f_1(1285)$ identity, rather than the pseudoscalar $0^-$ $η(1295)$. The production mechanism is more consistent with $s$-channel decay of a high-mass $N^*$ state, and not with $t$-channel meson exchange. Decays to $ηππ$ go dominantly via the intermediate $a_0^\pm(980)π^\mp$ states, with the branching ratio $Γ(a_0π\text{ (no} \bar{K} K\text{)}) / Γ(ηππ\text{(all)}) = 0.74\pm0.09$. The branching ratios $Γ(K \bar{K} π)/Γ(ηππ) = 0.216\pm0.033$ and $Γ(γρ^0)/Γ(ηππ) = 0.047\pm0.018$ were also obtained. The first is in agreement with previous data for the $f_1(1285)$, while the latter is lower than the world average.
description: 26 pages, 16 figures, Reference added, submitted to Physical Review C
Robots That Can See: Leveraging Human Pose for Trajectory Prediction
Creators: name: Salzmann, Tim
name: Chiang, Lewis
name: Ryll, Markus
name: Sadigh, Dorsa
name: Parada, Carolina
name: Bewley, Alex
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Human-Computer Interaction (cs.HC)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Anticipating the motion of all humans in dynamic environments such as homes and offices is critical to enable safe and effective robot navigation. Such spaces remain challenging as humans do not follow strict rules of motion and there are often multiple occluded entry points such as corners and doors that create opportunities for sudden encounters. In this work, we present a Transformer based architecture to predict human future trajectories in human-centric environments from input features including human positions, head orientations, and 3D skeletal keypoints from onboard in-the-wild sensory information. The resulting model captures the inherent uncertainty for future human trajectory prediction and achieves state-of-the-art performance on common prediction benchmarks and a human tracking dataset captured from a mobile robot adapted for the prediction task. Furthermore, we identify new agents with limited historical data as a major contributor to error and demonstrate the complementary nature of 3D skeletal poses in reducing prediction error in such challenging scenarios.
description: Project page: https://human-scene-transformer.github.io/
Understanding the optical properties of doped and undoped 9-armchair graphene nanoribbons in dispersion
Creators: name: Lindenthal, Sebastian
name: Fazzi, Daniele
name: Zorn, Nicolas F.
name: Yumin, Abdurrahman Ali El
name: Settele, Simon
name: Weidinger, Britta
name: Blasco, Eva
name: Zaumseil, Jana
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Graphene nanoribbons are one-dimensional stripes of graphene with width- and edge-structure-dependent electronic properties. They can be synthesized bottom-up in solution to obtain precise ribbon geometries. Here we investigate the optical properties of solution-synthesized 9-armchair graphene nanoribbons (9-aGNRs) that are stabilized as dispersions in organic solvents and further fractioned by liquid cascade centrifugation (LCC). Absorption and photoluminescence spectroscopy reveal two near-infrared absorption and emission peaks whose ratios depend on the LCC fraction. Low-temperature single-nanoribbon photoluminescence spectra suggest the presence of two different nanoribbon species. Based on density functional theory (DFT) and time-dependent DFT calculations, the lowest energy transition can be assigned to pristine 9-aGNRs, while 9-aGNRs with edge-defects, caused by incomplete graphitization, result in more blue-shifted transitions and higher Raman D/G-mode ratios. Hole doping of 9-aGNR dispersions with the electron acceptor F4TCNQ leads to concentration dependent bleaching and quenching of the main absorption and emission bands and the appearance of redshifted, charge-induced absorption features but no additional emission peaks, thus indicating the formation of polarons instead of the predicted trions (charged excitons) in doped 9-aGNRs.
An apparent positive relation between spin and orbital angular momentum in X-ray binaries
Creators: name: Yan, Zhen
name: Zhang, Wenda
name: Yu, Wenfei
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The origin of current angular momentum (AM) of the black hole (BH) in X-ray binary (XRB) is still unclear, which is related with the birth and/or the growth of the BH. Here we collect the spin parameters $a_{*}$ measured in BH XRBs and find an apparent bimodal distribution centered at $\sim$ 0.17 and 0.83. We find a positive relation between the spin parameter and the orbital period/orbital separation through combining distinct XRB categories, including neutron star (NS) low-mass X-ray binaries (LMXBs), Roche-lobe overflow (RLOF) BH XRBs and wind-fed BH XRBs. It seems that the AM of the compact star and the binary orbit correlates by combining the different XRB systems. These positive relations imply that accretion process is a common mechanism for spinning up the compact star in these diverse XRB systems. We infer that the low and high spin BH XRBs may experience different evolution and accretion history, which corresponds to the bimodal distribution of the BH spin parameters. The low spin BHs ($a_{*}<0.3$) are similar to the NS LMXBs, the compact star of which is spun-up by the low-level accretion, and the high spin BHs ($a_{*}>0.5$) had experienced a short hypercritical accretion ($\gg \dot{M}_\mathrm{Edd}$) period, during which, the BH spin dramatically increased.
description: 13 pages, 7 figures, accepted for publication in MNRAS
Polycyclic Aromatic Hydrocarbon Size Tracers
Creators: name: Maragkoudakis, A.
name: Peeters, E.
name: Ricca, A.
name: Boersma, C.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We examine the dependence of polycyclic aromatic hydrocarbon (PAH) band intensity ratios as a function of the average number of carbon atoms and assess their effectiveness as tracers for PAH size, utilising the data, models, and tools provided by the NASA Ames PAH Infrared Spectroscopic Database. To achieve this, we used spectra from mixtures of PAHs of different ionisation fractions, following a size distribution. Our work, congruent with earlier findings, shows that band ratios that include the 3.3 $μ$m PAH band provide the best PAH size tracers for small-to-intermediate sized PAHs. In addition, we find that band ratios that include the sum of the 15-20 $μ$m PAH features (I$_{Σ_{15-20}}$) and the 6.2 or 7.7 $μ$m bands also serve as good tracers for PAH size in the case of small-to-intermediate sized PAHs, for objects under a similar PAH size distribution as with the presented models. For different PAH size distributions, the application of a scaling factor to the I$_{6.2}$/I$_{Σ_{15-20}}$ ratio can provide estimates for the size of the small-to-intermediate PAH population within sources. Employment of the I$_{6.2}$/I$_{Σ_{15-20}}$ and I$_{7.7}$/I$_{Σ_{15-20}}$ ratios can be of particular interest for JWST observations limited only to $\sim$ 5-28 $μ$m MIRI(-MRS) coverage.
description: 8 pages, 5 figures; Accepted for publication in MNRAS
A Comparative Analysis on Metaheuristic Algorithms Based Vision Transformer Model for Early Detection of Alzheimer's Disease
Creators: name: Sen, Anuvab
name: Sen, Udayon
name: Roy, Subhabrata
Publisher: name: arXiv
Year: 2024
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: A number of life threatening neuro-degenerative disorders had degraded the quality of life for the older generation in particular. Dementia is one such symptom which may lead to a severe condition called Alzheimer's disease if not detected at an early stage. It has been reported that the progression of such disease from a normal stage is due to the change in several parameters inside the human brain. In this paper, an innovative metaheuristic algorithms based ViT model has been proposed for the identification of dementia at different stage. A sizeable number of test data have been utilized for the validation of the proposed scheme. It has also been demonstrated that our model exhibits superior performance in terms of accuracy, precision, recall as well as F1-score.
description: 2023 IEEE 15th International Conference on Computational Intelligence and Communication Networks (CICN). arXiv admin note: text overlap with arXiv:2309.16796
Basalys singularis Nixon 1980
Creators: name: Notton, David G.
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Diapriidae
Basalys
Basalys singularis

description: Basalys singularis Nixon, 1980: 28.
Valid name
Basalys singularis Nixon, 1980.
Summary of types
Holotype ♀, BMNH number 9.823, by original designation. Paratype ♀.
Primary type data
Furry Glen/ Co. Du., A.W.S./ 26.9.37; Ireland / A.W.Stelfox coll./ BMNH 1949-110; Basalys / singularis/ Nixon/ type ♀, 197.
Type locality
Ireland, County Dublin, Furry Glen.
Remarks
The holotype is mounted on a card and is entire.
description: Published as part of Notton, David G., 2014, A catalogue of the types of Diapriinae (Hymenoptera, Diapriidae) at the Natural History Museum, London, pp. 1-123 in European Journal of Taxonomy 75 on page 98, DOI: 10.5852/ejt.2014.75, http://zenodo.org/record/3862773
Regime change detection in irregularly sampled time series
Creators: name: Marwan, Norbert
name: Eroglu, Deniz
name: Ozken, Ibrahim
name: Stemler, Thomas
name: Wyrwoll, Karl-Heinz
name: Kurths, Jürgen
Publisher: name: arXiv
Year: 2024
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Chaotic Dynamics (nlin.CD)
subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: FOS: Physical sciences

description: Irregular sampling is a common problem in palaeoclimate studies. We propose a method that provides regularly sampled time series and at the same time a difference filtering of the data. The differences between successive time instances are derived by a transformation costs procedure. A subsequent recurrence analysis is used to investigate regime transitions. This approach is applied on speleothem based palaeoclimate proxy data from the Indonesian-Australian monsoon region. We can clearly identify Heinrich events in the palaeoclimate as characteristic changes in the dynamics.
description: 12 pages, 3 figures
Phononic transport in 1T prime-MoTe2: anisotropic structure with an isotropic lattice thermal conductivity
Creators: name: Cui, Xiangyue
name: Yan, Xuefei
name: Wang, Bowen
name: Cai, Yongqing
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Molybdenum ditelluride (MoTe2) is an unique transition metal dichalcogenide owing to its energetically comparable 1H and 1T prime phases. This implies a high chance of coexistence of 1H-1T prime heterostructures which poses great complexity in the measurement of the intrinsic lattice thermal conductivities (kappa). In this work, via first-principles calculations, we examine the lattice-wave propagation and thermal conduction in this highly structurally anisotropic 1T prime MoTe2. Our calculation shows that the 1T prime phase has a sound velocity of 2.13 km/s (longitudinal acoustic wave), much lower than that of the 1H phase (4.05 km /s), indicating a staggered transmission of lattice waves across the boundary from 1H to 1T prime phase. Interestingly, the highly anisotropic 1T prime MoTe2 shows nearly isotropic and limited kappa_L of 13.02 W/mK, owing to a large Gruneisen parameter of acoustic flexural mode, heavy masses of Mo and Te elements and a low phonon group velocity. Accumulative kappa_L as a function of mean free path (MFP) indicates phonons with MFP less than ~300 nm contribute 80% of kappa_L and an inflection point at ~600 nm. Our results will be critical for understanding of the size dependent kappa_L of nanostructured 1T prime MoTe2.
Analysis of the possible satellite contamination in LAMOST-MRS spectra
Creators: name: Kovalev, Mikhail
name: Hainaut, Olivier R.
name: Chen, Xuefei
name: Han, Zhanwen
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We present the detection of false positive double-lined spectroscopic binaries candidates (SB2) using medium-resolution survey (MRS) spectra from the one time-domain field of LAMOST data release 10 (DR10). The secondary component in all these binaries has near zero radial velocity and solar-like spectral lines. Highly likely this is light from the semi-transparent clouds illuminated by the full Moon. However we also suspect that partially this contamination can be caused by a solar light reflected from the surface of low-orbital artificial satellites launched in the beginning of 2022. We found several possible contaminant candidates using archival orbital data. We propose measures to reduce risk of such contamination for the future observations and methods to find it in archived ones.
description: accepted in MNRAS letters 2023 July 07
Phenomenological QCD equations of state for neutron stars
Creators: name: Kojo, Toru
name: Powell, Philip D.
name: Song, Yifan
name: Baym, Gordon
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We delineate the properties of QCD matter at baryon density n_B=1-10n_0 (n_0: nuclear saturation density), through the construction of neutron star equations of state that satisfy the neutron star mass-radius constraints as well as physical conditions on the speed of sound. The QCD matter is described in the 3-window modeling: at n_B < 2n_0 purely nuclear matter; at n_B > 5n_0 percolated quark matter; and at 2n_0 < n_B < 5n_0 matter intermediate between these two which are constructed by interpolation. Using a schematic quark model with effective interactions inspired from hadron and nuclear physics, we analyze the strength of interactions necessary to describe observed neutron star properties. Our finding is that the interactions should remain as strong as in the QCD vacuum, indicating that gluons at n_B =1-10 n_0 remain non-perturbative even after quark matter formation.
description: 5 pages, 3 figures, proceedings of the XXV Quark Matter conference, Sep. 27 to Oct. 3 in 2015, Kobe (Japan)
Diurnal ejection of boulder clusters on comet 67P lasting beyond 3 AU
Creators: name: Shi, Xian
name: Hu, Xuanyu
name: Agarwal, Jessica
name: Güttler, Carsten
name: Rose, Martin
name: Keller, Horst Uwe
name: Fulle, Marco
name: Deller, Jakob
name: Sierks, Holger
Publisher: name: arXiv
Year: 2024
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Ejection of large boulder-like debris is a vigorous form of cometary activity that is unlikely induced by water ice out-gassing alone but rather associated with the sublimation of super-volatile ices. Though perceived on several comets, actual pattern and mechanism of such activity are still unclear. Here we report on a specialized observation of ejections of decimeter- to meter-sized boulders on comet 67P/Churyumov-Gerasimenko outbound between 2.5 and 3.3 AU from the Sun. With a common source region, these events recurred in local morning. The boulders of elongated shapes were ejected in clusters at low inclinations comparable to the solar elevation below 40 degrees at the time. We show that these chunks could be propelled by the surrounding, asymmetric gas field that produced a distinct lateral acceleration. Possibly both water and carbon dioxide have contributed to their mobilization, while the season and local topography are among deciding factors. The mechanisms for sustaining regular activity of comets at large heliocentric distances are likely more diverse and intricate than previously thought.
Automatically detecting activities of daily living from in-home sensors as indicators of routine behaviour in an older population
Creators: name: Timon, Claire M.
name: Hussey, Pamela
name: Lee, Hyowon
name: Murphy, Catriona
name: Rai, Harsh Vardan
name: Smeaton, and Alan F.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Objective: The NEX project has developed an integrated Internet of Things (IoT) system coupled with data analytics to offer unobtrusive health and wellness monitoring supporting older adults living independently at home. Monitoring {currently} involves visualising a set of automatically detected activities of daily living (ADLs) for each participant. The detection of ADLs is achieved {} to allow the incorporation of additional participants whose ADLs are detected without re-training the system. Methods: Following an extensive User Needs and Requirements study involving 426 participants, a pilot trial and a friendly trial of the deployment, an Action Research Cycle (ARC) trial was completed. This involved 23 participants over a 10-week period each with c.20 IoT sensors in their homes. During the ARC trial, participants each took part in two data-informed briefings which presented visualisations of their own in-home activities. The briefings also gathered training data on the accuracy of detected activities. Association rule mining was then used on the combination of data from sensors and participant feedback to improve the automatic detection of ADLs. Results: Association rule mining was used to detect a range of ADLs for each participant independently of others and was then used to detect ADLs across participants using a single set of rules {for each ADL}. This allows additional participants to be added without the necessity of them providing training data. Conclusions: Additional participants can be added to the NEX system without the necessity to re-train the system for automatic detection of the set of their activities of daily living.
description: 11 pages, 7 Figures, 2 tables
title: Probing Cytoskeletal Scaffolding and Mechanical Integrity of Cells in Disease with Atomic Force Microscopy
Creators: name: Amiri, Anahid
Publisher: name: UNSPECIFIED
Year: 2024

description: The morphological, structural, and mechanical alterations of cancer cells are pivotal during cancer
development, facilitating effective metastasis. In this regard, understanding cytoskeletal changes in cancer is
essential for developing targeted therapeutic strategies aimed at disrupting cancer cells’ progression in invasion,
and metastasis through cytoskeletal manipulations. In this dissertation high-resolution quantitative
nanomechanical characterization, 3D stiffness tomography, and 3D confocal microscopy were employed to
examine the cellular cytoskeleton scaffolding and its integrity within cancer cells. This in-depth exploration of
mechanical and physical variances associated with cellular transformations in cancer provided an extensive
analysis of the mechanical and dynamic changes of cytoskeletal elements in epithelial-type progressive cancers
through several contact mechanics models and filaments’ persistence length measure. Our investigation primarily
centered on breast cancer cells, highlighting the roles of microtubules and the cytolinker protein plectin in
reducing cellular stiffness compared to normal cells. These findings were then extrapolated to other lethal cancers,
including those affecting the liver, lung, and skin, to understand broader implications. We found significant
variability in cytoskeletal filament expression and configuration, primarily due to the positioning of basal
microtubules caused by cytoskeletal cross-linking disruptions. Paclitaxel, a cytoskeletal stabilizing drug, was
shown to restore the microtubule network and plectin cytoskeletal structure in invasive carcinoma cells. It
facilitated the reassembly of microtubules beneath the cell membrane and repositioned plectin, enhancing cellular
mechanical integrity. Additionally, paclitaxel increased the correlation between tubulin and actin, suggesting
enhanced cytoskeletal organization. This reorganization involving the three primary cytoskeletal components,
may reduce the malignant cell's ability to extend across the anatomical micropores, that requires further study.
Revealing recurrent regimes of mid-latitude atmospheric variability using novel machine learning method
Creators: name: Mukhin, Dmitry
name: Hannachi, Abdel
name: Braun, Tobias
name: Marwan, Norbert
Publisher: name: arXiv
Year: 2024
Subjects: subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: FOS: Physical sciences

description: The low frequency variability of the extratropical atmosphere involves hemispheric-scale recurring, often persistent, states known as teleconnection patterns or regimes, which can have profound impact on predictability on intra-seasonal and longer timescales. However, reliable data-driven identification and dynamical representation of such states are still challenging problems in modeling dynamics of the atmosphere. We present a new method, which allows both to detect recurring regimes of atmospheric variability, and to obtain dynamical variables serving as an embedding for these regimes. The method combines two approaches from nonlinear data analysis: partitioning a network of recurrent states with studying its properties by the recurrence quantification analysis and the kernel principal component analysis. We apply the method to study teleconnection patterns in a quasi-geostrophical model of atmospheric circulation over the extratropical hemisphere as well as to reanalysis data of geopotential height anomalies in the mid-latitudes of the Northern Hemisphere atmosphere in the winter seasons from 1981 to the present. It is shown that the detected regimes as well as the obtained set of dynamical variables explain large-scale weather patterns, which are associated, in particular, with severe winters over Eurasia and North America. The method presented opens prospects for improving empirical modeling and long-term forecasting of large-scale atmospheric circulation regimes.
description: 20 pages, 14+3 figures
On The 2D Phase Retrieval Problem
Creators: name: Kogan, Dani
name: Eldar, Yonina C.
name: Oron, Dan
Publisher: name: arXiv
Year: 2016
Subjects: subject: Information Theory (cs.IT)
subject: Optimization and Control (math.OC)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: The recovery of a signal from the magnitude of its Fourier transform, also known as phase retrieval, is of fundamental importance in many scientific fields. It is well known that due to the loss of Fourier phase the problem in 1D is ill-posed. Without further constraints, there is no unique solution to the problem. In contrast, uniqueness up to trivial ambiguities very often exists in higher dimensions, with mild constraints on the input. In this paper we focus on the 2D phase retrieval problem and provide insight into this uniqueness property by exploring the connection between the 2D and 1D formulations. In particular, we show that 2D phase retrieval can be cast as a 1D problem with additional constraints, which limit the solution space. We then prove that only one additional constraint is sufficient to reduce the many feasible solutions in the 1D setting to a unique solution for almost all signals. These results allow to obtain an analytical approach (with combinatorial complexity) to solve the 2D phase retrieval problem when it is unique.
Physical properties of circumnuclear ionising clusters. I. NGC 7742
Creators: name: Zamora, S.
name: Díaz, A. I.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: This work aims to derive the physical properties of the CNSFRs in the ring of the face-on spiral NGC 7742 using IFS observations. We have selected 88 individual ionising clusters that power HII regions populating the ring of the galaxy that may have originated in a minor merger event. For the HII regions the rate of Lyman continuum photon emission is between 0.025 and 1.5 10$^{51}$ which points to these regions being ionised by star clusters. Their electron density, ionisation parameter, filling factor and ionised hydrogen mass show values consistent with those found in other studies of similar regions and their metal abundances as traced by sulphur have been found to be between 0.25 and 2.4 times solar, with most regions showing values slightly below solar. The equivalent temperature of the ionising clusters is relatively low, below 40000 K which is consistent with the high elemental abundances derived. The young stellar population of the clusters has contributions of ionising and non-ionising populations with ages around 5 Ma and 300 Ma respectively. The masses of ionising clusters once corrected for the contribution of underlying non-ionising populations were found to have a mean value of 3.5 $\times$ 10$^4$ M$_{\odot}$, comparable to the mass of ionised gas and about 20 \% of the corrected photometric mass.
description: 23 pages, 21 figures, accepted for publication in MNRAS;
Phase space representation of non-Hermitian system with $\mathcal{PT}$-symmetry
Creators: name: Praxmeyer, Ludmila
name: Yang, Popo
name: Lee, Ray-Kuang
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We present a phase space study of non-Hermitian Hamiltonian with $\mathcal{PT}$-symmetry based on the Wigner distribution function. For an arbitrary complex potential, we derive a generalized continuity equation for the Wigner function flow and calculate the related circulation values. Studying vicinity of an exceptional point, we show that a $\mathcal{PT}$-symmetric phase transition from an unbroken $\mathcal{PT}$-symmetry phase to a broken one is a second-order phase transition.
Correlations between QPO frequencies and spectral parameters of GRS 1915+105 using AstroSat observations
Creators: name: Dhaka, Ruchika
name: Misra, Ranjeev
name: Yadav, JS
name: Jain, Pankaj
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: In this work, we study the correlation between Quasi-periodic Oscillation (QPO) frequency and the spectral parameters during various X-ray states in the black hole binary GRS 1915+105 which matches well with the predicted relativistic dynamic frequency (i.e. the inverse of the sound crossing time) at the truncated radii. We have used broadband data of LAXPC and SXT instruments onboard AstroSat. Spectral fitting shows that the accretion rate varies from $\sim 0.1$ to $\sim 5.0 \times 10^{18}$ gm/s and the truncated radius changing from the last stable orbit of an almost maximally spinning black hole, $\sim$ 1.2 to $\sim$ 19 Gravitational radii. For this wide range, the frequencies of the C-type QPO (2 - 6 Hz) follow the trend predicted by the relativistic dynamical frequency model and interestingly, the high-frequency QPO at $\sim$ 70 Hz also follows the same trend, suggesting they originate from the innermost stable circular orbit with the same mechanism as the more commonly observed C-type QPO. While the qualitative trend is as predicted, there are quantitative deviations between the data and the theory, and the possible reasons for these deviations are discussed.
Digital Transformation of Language Centres: an approach based on the TOE Framework
Creators: name: Τερμεντζόγλου, Μαρία Κωνσταντίνου
Publisher: name: Aristotle University of Thessaloniki
Year: 2024
Subjects: Ψηφιακός μετασχηματισμός
Ψηφιακή ωρίμανση
ΤΟΕ πλαίσιο
Digital transformation
Digital maturity
TOE framework

description: Στόχος της παρούσας διατριβής είναι να διερευνήσει τους παράγοντες που επηρεάζουν τα κέντρα ξένων γλωσσών στην απόφασή τους να ενσωματώσουν την τεχνολογία στις εκπαιδευτικές τους πρακτικές. Η έρευνα διεξάγεται με τη χρήση του πλαισίου Τεχνολογίας, Οργάνωσης και Περιβάλλοντος (Τ.Ο.Ε.), το οποίο παρέχει μια δομημένη προσέγγιση για την κατανόηση της πολύπλοκης αλληλεπίδρασης των στοιχείων που επηρεάζουν αυτή την ενσωμάτωση. Στόχος της έρευνας είναι να εντοπίσει τους παράγοντες που συμβάλλουν στο να ωθήσουν τα κέντρα ξένων γλωσσών όχι μόνο να υιοθετήσουν την τεχνολογία, αλλά και να γίνουν ψηφιακά ώριμοι οργανισμοί. Ρίχνει φως στον τρόπο με τον οποίο οι εσωτερικές διοικητικές διαδικασίες των γλωσσικών κέντρων λειτουργούν με τη βοήθεια της τεχνολογίας ή όχι και στον τρόπο με τον οποίο οι οργανωτικές δομές μπορούν είτε να διευκολύνουν είτε να εμποδίσουν την ενσωμάτωση της τεχνολογίας. Στόχος είναι η κατανόηση των οργανωτικών παραγόντων που συμβάλλουν σε ένα ευνοϊκό περιβάλλον για την επιτυχή ενσωμάτωση της τεχνολογίας. Γίνεται επίσης σχολαστική αναφορά στους εξωτερικούς παράγοντες που επηρεάζουν τις αποφάσεις των κέντρων ξένων γλωσσών, όπως η παγκοσμιοποίηση, η πρόοδος των τεχνολογιών επικοινωνίας, η άνοδος της εξ αποστάσεως εκπαίδευσης ή ακόμη και ο έντονος ανταγωνισμός στον κλάδο. Στόχος της έρευνας είναι να αποκαλύψει πώς τα κέντρα ξένων γλωσσών ανταποκρίνονται στις απαιτήσεις ενός ταχέως μεταβαλλόμενου κόσμου και προσαρμόζουν ανάλογα τις εκπαιδευτικές τους πρακτικές.
description: This dissertation aims to investigate the factors that influence language centres in their decision to integrate technology into their educational practices. The investigation is conducted using the Technology, Organization, and Environment (T.O.E) framework, which provides a structured approach to understanding the complex interplay of elements affecting this integration. Thε research aims to identify the contributing factors that push language centres to not only adopt technology, but also to become digitally mature organisations. It sheds light on the way internal managerial processes of language centres operate with the assistance of technology or not and how organisational structures can either facilitate or hinder the integration of technology. The aim is to comprehend the organizational factors that contribute to a favourable environment for successful technology integration. Meticulous reference is also made to the external factors that affect language centres' decisions, such as globalization, advancements in communication technologies,the rise of remote learning or even fierce competition in the industry. The research aims to reveal how language centres respond to the demands of a rapidly changing world and adjust their educational practices accordingly.
Optical Memory for Arbitrary Perfect Poincaré States in an Atomic Ensemble
Creators: name: Zeng, Lei
name: Ye, Ying-Hao
name: Dong, Ming-Xin
name: Zhang, Wei-Hang
name: Li, En-Ze
name: Ding, Dong-Sheng
name: Shi, Bao-Sen
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Inherent spin angular momentum (SAM) and orbital angular momentum (OAM) which manifest as polarization and spatial degrees of freedom (DOF) of photons, hold a promise of large capability for applications in classical and quantum information processing. To enable these photonic spin and orbital dynamic properties strongly coupled with each other, Poincaré states have been proposed and offer advantages in data multiplexing, information encryption, precision metrology, and quantum memory. However, since the transverse size of Laguerre Gaussian beams strongly depends on their topological charge numbers $\left| l \right|$, it is difficult to store asymmetric Poincaré states due to the significantly different light-matter interaction for distinct spatial modes. Here, we experimentally realize the storage of perfect Poincaré states with arbitrary OAM quanta using the perfect optical vortex, in which 121 arbitrarily-selected perfect Poincaré states have been stored with high fidelity. The reported work has great prospects in optical communication and quantum networks for dramatically increased encoding flexibility of information.
Conditionally expectations and martingales in noncommutative $L_p$-spaces associated with center-valued traces
Creators: name: Ganiev, Inomjon
name: Mukhamedov, Farrukh
Publisher: name: arXiv
Year: 2016
Subjects: subject: Operator Algebras (math.OA)
subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 46L52, 46L53

description: In this paper we prove the existence of conditional expectations in the noncommutative $L_p(M,Φ)$ spaces associated with center-valued traces. Moreover, their description is also provided. As an application of the obtained results, we establish the norm convergence of the martingales in noncommutative $L_p(M,Φ)$ spaces.
description: 16 pages. arXiv admin note: substantial text overlap with arXiv:1603.07812; text overlap with arXiv:1007.1878 by other authors